Eye Exercises for People With Cataracts

StrongSight Vision by Dr. Benjamin Miller

Dr. Benjamin Miller says that the steps given in the Easy Clear Vision guide make it is possible to get perfect 20/20 vision without wearing unattractive & highly breakable glasses or uncomfortable & even painful contact lenses and without undergoing any risky & expensive eye surgery. Further he explains that you dont have to invest anything in vision enhancing products once you follow the steps in his guide. Glasses and lenses are not the treatment for weak eyesight in fact long use of glasses or lenses can make eyesight even worst. They can create lack of focus in the future. But by using proper holistic approach you can increase the functionality of eye muscles and on other hand you can improve your eyesight as well. This is where you can get help from Dr. Benjamins Easy Clear Vision. So, if you want you know if this program will work for you or not then you have to test it yourself. You will feel secure to know that Dr. Benjamin offering 60-days money back guarantee. You have 60-days to test this program and if you dont get any results then you can return it back to the author and get your money back.

Easy Clear Vision Summary

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Lens Displacement and Traumatic Cataract

A cataract is present when the lens becomes opaque, and in extreme cases the lens may appear totally white. In acute traumatic cataract the opacity of the lens may be very slight and may be difficult to see. In some children I have seen marked swelling of the lens almost entirely as the result of increased clear fluid beneath the posterior lens capsule (posterior lenticonus). Such changes should be fully documented, but their traumatic significance is disputed by some. Cataract formation is a well-recognized and common consequence of blunt ocular trauma, and in blunt trauma it results from contusion or concussion to the lens.37'38 Traumatic cataracts often develop immediately after injury and are evident when the patient presents to the hospital,37 although some traumatic cataracts develop over weeks or months. Some cataracts have a rosette petal-shaped form of opacity and appear within a few hours of the injury.38 After concussion of the lens, the capsule of the lens may be severed...

Medical Therapy Of Glaucoma

Medical treatment for glaucoma involves multiple medications (Table 2) 3, 5, 10 . The principal goal of medical treatment is lowering of intraocular pressure. Local administration of cholinergic agents, beta-adrenergic blockers, and alpha- TABLE 1 Classification of Glaucoma 1. Congenital glaucoma 2. Primary glaucoma a. Open angle glaucoma b. Closed angle glaucoma 3. Secondary glaucoma TABLE 2 Medical Therapy of Glaucoma adrenergic agonists have been used to treat glaucoma. Cholinergic agents, with the prototype drug pilocarpine, lower intraocular pressure by stimulation of the ciliary muscle and by constriction of the pupil, with the resultant reduction of trabecular resistance to aqueous humor outflow. Beta-adrenergic antagonists, with the prototype drug timolol, lower intraocular pressure by blockade of the ciliary process production of aqueous humor. Alpha-adrenergic agonists, with the prototype drug epinephrine lower intraocular pressure by stimulation of receptors in the...

Ophthalmic Surgery Cataract Surgery

Cataracts may be congenital, traumatic, steroid- or radiation-induced, or degenerative. In degenerative cataracts there will also be other medical conditions of the ageing population. While diabetics have no more cataracts than the general population, they tend to present earlier and so there seems to be a preponderance of diabetic patients presenting for cataract surgery. Steroid induced cataracts present in patients taking long term steroids for other conditions, particularly eczema or asthma which should be taken into account. Cataract surgery demands a still eye with low intra-ocular pressure. This can usually be achieved by smooth anaesthesia with muscle relaxation and IPPV to achieve mild hypocapnia, whether via a tracheal tube or laryngeal mask, though the latter is preferable because of the lack of intubation pressor response or laryngeal spasm and coughing on extubation. There is a fashion for local anaesthesia for cataract surgery despite this having a higher failure rate,...

Cataracts and Photoreceptors

Several micronutrients, especially those that can have antioxidant functions in living tissues, have recently been investigated in relation to possible protection against degenerative eye diseases, such as cataract. Studies in animal models have suggested, albeit indirectly, that riboflavin status may be important here, and several recent epidemiologi-cal studies, including an intervention study in one region of China, have supported the suggestion that

Macular Degeneration and Cataracts

The eye is at particular risk of oxidative damage due to high oxygen concentrations, large amounts of oxidizable fatty acids in the retina, and exposure to ultraviolet rays. In Western countries, age-related macular degeneration (AMD) is the leading cause of blindness among older people. Cataracts are also widespread among the elderly and occur when the lens is unable to function properly due to the formation of opacities within the lens. These develop when proteins in the eye are damaged by photooxidation these damaged proteins build up, clump, and precipitate. It has been proposed that antioxidants may prevent cellular damage in the eye by reacting with free radicals produced during the process of light absorption. The results of intervention trials in this area have also been mixed. The Age-Related Eye Disease Study in the United States investigating the effects of combined antioxidant vitamins C (500 mg), E (400 IU), and -carotene (15 mg) with and without 80 mg zinc daily for 6...

Dietary n3 Deficiency in the Mouse 721 Mouse Visual Acuity and n3 Deficiency

As seen in rats, there is no evidence of a strong correlation between visual acuity and learning in the mouse. The second generation of mice (F1) fed a diet poor in LNA was compared to a group fed laboratory chow. In adult mice, there was a significant difference in the retinal concentration of DHA, but the difference in b-wave electroretinograms ceased to be significant at the seventh week (Carrie, et al., 1999). The ability to learn was examined using the passive-avoidance test and the LNA-deficient group continued to The data on behavior for the mouse is less consistent than the data on visual acuity, even if most studies point to beneficial effects of a diet enriched in DHA and its precursor LNA. Wainright (Wainright, et al., 1994) fed mice one of three diets through pregnancy, lactation, and weaning. They were the same basic diet but with (1) saturated fat, (2) adequate LA but deficient in LNA, and (3) sufficient LNA and LA (n-6 n-3 ratio of 3.7). Six weeks after weaning, two...

Diuretics and Glaucoma

Glaucoma is a series of eye diseases characterized by increased intraocular pressure, optic nerve degeneration, and visual field defects 3, 4, 8 . It is one of the leading causes of blindness in the United States. The incidence of the disease increases with advancing age and ranges from 1 to 5 of adults over the age of 40. The disease is insidious in its origin and most patients are asymptomatic until late in the course of the illness. By the time the diagnosis of glaucoma is made, permanent visual loss often has already occurred. The primary basis of glaucoma is an increase in intraocular pressure (greater than 20-24 Torr) leading to progressive deterioration of the optic nerve 3, 4,8 . The mechanism of the increased intraocular pressure is an obstruction to aqueous humor outflow from the posterior chamber, from the anterior chamber through the trabecular meshwork on the way to the canal of Schlemm into the venous drainage system, or via drainage through uveal vessels and the sclera....

Classification Of Glaucoma

Glaucoma is not a single disorder, but rather multiple disorders (Table 1). There are multiple classification schemes. Glaucoma can be classified into congenital glaucoma, primary glaucoma, and secondary glaucoma. Congenital glaucoma is caused by an abnormality in the aqueous humor outflow tract in the anterior chamber. There may be other associated developmental ocular abnormalities. Primary glaucoma is divided into two categories, primary open angle glaucoma, and primary closed angle glaucoma. Primary open angle glaucoma is the most common form of glaucoma 9 . It is caused by chronic obstruction of outflow of aqueous humor from the anterior chamber through the trabecular network. The angle between the iris and the cornea is open and there is free passage of aqueous humor from the posterior chamber to the anterior chamber. The reported causes of obstruction at the level of the trabecular network are multiple and include accumulation of debris in the trabecular network, loss of the...

Ophthalmologic Infections

Ophthalmologic infections in the IVDU are usually the result of hematogenous seeding from a primary source of infection, such as endocarditis, or of opportunistic infections associated with coincident HIV disease. Bacterial endophthlamitis often presents acutely, with rapid progression of pain, redness, lid swelling, and decrease in visual acuity.46 Inflammation is usually present in the anterior and posterior chambers. White-centered, flame-shaped hemorrhages (Roth spots), cotton wool exudates, and macular holes may be present. S. aureus is the most commonly isolated organism, followed by Streptococcus sp. A rare but rapidly destructive infection has been reported with Bacillus cereus. Treatment involves subconjunctival and systemic antibiotic therapy surgical intervention may be needed. Fungal endophthalmitis, usually due to Candida, is more common than bacterial endophthalmitis. The clinical picture is often indolent, progressing over days to weeks. Symptoms include blurred vision,...

Ophthalmologic Manifestations

Seventy-five percent of patients with AIDS develop ocular complications. Although a wide range of ophthalmic diseases occur, recognition of a few is most critical. 22 The most common ophthalmic finding in patients with AIDS is retinal microvasculopathy, which is characterized by retinal cotton-wool spots identical in appearance to those of diabetes or hypertension. Retinal microaneurysms are also seen, primarily in the periphery. These lesions are believed to be incidental and do not cause visual disturbances. The diagnostic dilemma is to distinguish these findings from early CMV infection, and ophthalmologic consultation is recommended. CMV retinitis is the most frequent and serious ocular opportunistic infection and the leading cause of blindness in AIDS patients. The prevalence is estimated to be up to 40 percent. Visual loss and blindness occur in all cases without early detection and prompt treatment. 23 The presentation of CMV retinitis is variable. It may be asymptomatic early...

Visual Factors Perception of the Image

Figure Ground Perception Examples

This allows for the greatest visual acuity when the image is focused on the fovea centralis. However, this is a relatively small area owing to the fact that the cones, which are responsible for visual acuity, are concentrated at the fovea, especially at its center, and this accounts for the rapid decline in acuity just a few degrees from the fovea centralis. Of necessity, then, peripheral vision is used as the initial step in reading a radiograph. Use of peripheral vision allows for a considerably larger, although not as acute, field of vision in which to select possible abnormal areas from numerous areas of suboptimal quality images projected on the retina. There is a direct relationship between visual field size and the time required to locate a target.1 After an object of possible interest is located, the eye then moves to a position that focuses the fovea centralis on this point. In this position, detailed information can be obtained. In addition to...

Xanthophylls Lutein and Zeaxanthin

Free radical damage is also linked to the development of cataracts. Cataracts remain the leading cause of visual disability in the US and about one-half of the 30-50 million cases of blindness throughout the world. Although cataracts are treatable, blindness occurs because individuals have either chosen not to correct the disease or do not have access to the appropriate medical treatment. Several epidemiological studies have shown inverse associations between the risk of cataracts and carotenoid intake. However, these studies also present inconsistencies with regard to the different carotenoids and their association with cataract risk. Lutein and zea-xanthin are found in the lens and are thought to protect cells in the eye against oxidative damage, and consequently prevent formation of cataracts. However, to date, there is no evidence that any carotenoid supplement can protect against cataract development. Eating plenty of fruits and vegetables, good sources of many antioxidants...

Mechanisms Of Cement Reaction

Montreal Mattress Surgery

The primary requirement of back surgery is the prone position. Adequate eye care is important and there is no substitute for endotracheal intubation (possibly with an armoured tube) and IPPV using individual drugs of choice. The patient's arms must be carefully and symmetrically moved when turning into the prone position to avoid shoulder dislocation and pressure points should be padded. A suitable support should be employed to avoid abdominal compression, which will both embarrass ventilation and cause venous congestion in the epidural plexus. The Montreal mattress and Toronto frame are frequently used (Figure SI.2).

Associative Agnosia

Examples Agnosia

One of the important claims of associative agnosia is that perception is intact and it is meaning that is inaccessible. Much effort has been directed at evaluating this claim and the general finding is that even patients with associative agnosia have some form of visual impairment. For example, LH, a well-known and thoroughly documented agnosic patient studied by Levine and Calvanio, was moderately impaired on several tests of perception. He was considerably slower than normal subjects in making rapid comparisons between shapes or in searching for a prespecified target figure. His performance was also poor on tasks that required him to identify letters that were fragmented or degraded by visual noise, relative to control subjects. Based on the findings from LH and other associative

Elimination By Aspects Theory

EMMERT'S LAW. size-distance invariance hypothesis. This generalized principle is named in honor of the Swiss ophthalmologist Emil Emmert (1844-1911) and refers to the tendency of a projected image (usually an afterimage) to increase in size in proportion to the distance to which it is projected onto a background surface. Emmert's law is also called the afterimage law cf., U. Ebbecke (1929) who proposed a theory of positive and negative afterimages. Another afterimage phenomenon is the McCollough effect color-contingent aftereffect - named after the American psychologist Celeste Faye McCol-lough (1926- ) - which is a persistent afterimage produced by saturating the eye with red and green patterns of different angularity in a typical demonstration, a pattern of bright red

The Foveation System

Smooth Pursuit System And The Brain

As in most primates, the human retina has a tremendously specialized central zone, the fovea, where visual acuity is 1000 times better than vision just 10 eccentric. Hence, to look at'' something is effectively to foveate it. However, the fovea subtends only 1 of visual angle (equivalent to the full moon's subtend). Therefore, the second principal function of eye movements is to foveate important parts of the visual scene.

TABLE 2311 Drugs that Can Cause Hypocalcemia

Idiopathic Hypoparathyroidism Idiopathic hypoparathyroidism is probably an autoimmune disorder in which pernicious anemia, exostoses, moniliasis, Hashimoto disease, sterility, and Addison disease may be seen. This syndrome may also be associated with cataracts, mental retardation, intracranial calcifications, and papilledema due to increased intracranial pressure.

Defining Disability Conceptual Issues

Thus, not every impairment is disabling. An abnormal shape of the eyeball that prevents light from focusing properly on the lens is an impairment, but if the afflicted person can see perfectly well with glasses or contact lenses and carry out the same activities that other people can, that impairment is not disabling. One also can ask whether a disability is a handicap. Franklin Delano Roosevelt had a disability (he could not walk) that no doubt prevented him from fulfilling some social roles, but it did not prevent him from fulfilling the role of president of the United States, and so in that respect it was not a handicap.

Brown Shrinkage Effect

Sulzer (1858-1918) also called the Brucke effect, named after the German physiologist Ernst W. Brucke (1819-1892) and the Brewster effect, named after the Scottish physicist David Brewster (1781-1868) - refers to the phenomenon that a flash of light appears to be brighter than a steady light of the same intensity . See also RICCO'S PIPER'S LAWS. REFERENCES

Medicine in Ethiopia

As we noted earlier in this chapter, e-medicine involves delivering health care using telecommunication equipment as simple as telephones and fax machines or as complex as Internet-connected personal computers with full-motion interactive multimedia (Huston and Huston, 2000). There is a critical need to better understand the factors affecting the diffusion of e-medicine in developing countries. Services such as teleradiology, teledermatology, telepathology, telecardiology, and tele-ophthalmology can be extended to underserved communities and individuals in both urban and rural areas. In addition, e-medicine can help attract and retain health professionals in rural areas by providing ongoing training and collaboration with other health professionals. Although e-medicine, like all information and communication technologies (ICTs), was developed and tested in developed countries, it has successfully addressed some medical problems in developing countries. However, many of these...

Pure Meaning Concept Of

Vitamin A or to a congenital retinal defect. In addition to the Purkinje effect, Purkinje's name is honored in the terms Purkinje figures - the network of interwoven blood vessels of the retina that may be perceived under conditions of low ambient illumination and when a small bright light is positioned just under the eye as the person stares at a blank screen or wall Purkinje-Sanson images - named after Purkinje and the French surgeon Louis Joseph Sanson (1790-1841), refers to the perception by one person (by looking at a second person's eye) of three separate images of an object that the second person looks at, where one image is from the surface of the cornea, one is from the back of the lens, and one is from the front of the lens and the Purkinje afterimage -is the second positive afterimage that follows stimulation by a bright light that is a hue complement to the original stimulus the first in the sequence of three visual afterimages following a brief exposure to a bright light...

Periorbital and Orbital Exam

Nasal Palpation

The eye exam deserves particular attention, especially when there is periorbital injury. The exam should be performed early during the ED encounter, because, if not timely, progressive lid edema may prevent further examination. If lids are already swollen, lid retractors help visualize the globe. The bird's-eye and worm's-eye views help detect exophthalmos or enophthalmos. The pupil exam includes reactivity, and whether the pupils line up in the horizontal plane. A teardrop-shaped pupil indicates a ruptured or otherwise penetrated globe in patients without preexisting iridectomy. Examine for hyphema, although this usually requires a patient to be sitting. The presence of a hyphema correlates with significant visual loss. The Snellen chart, either standard or hand held, if feasible to administer, should be used to document visual acuity. If the patient cannot see the chart, record finger counting or, barring that, the presence or absence of light perception. Early recognition of...

Herpes Zoster Shingles

HZO is due to involvement of the ophthalmic branch of CN V and is a vision-threatening condition. The Hutchinson sign (lesions on the tip of the nose) may be seen before ocular involvement is recognized, but its absence does not rule out HZO. 20 Ocular involvement can be seen in the presence of only a slight rash on the forehead. HZO induces a keratitis and may be followed by involvement of deeper structures. There is usually facial pain, regional adenopathy, and occasionally a red eye preceding the appearance of the rash. A dendriform corneal ulcer can often be identified with fluorescein staining. The presence of a skin rash helps differentiate HZO from ocular HSV. HZO or suspected HZO mandates an ophthalmologic consultation due to the threat to vision.

Tranquilizer Rescinnamine

Histidine-derived alkaloids include pilocarpine and saxi-toxin. Pilocarpine stimulates parasympathetic nerve endings and is used to treat glaucoma. The main commercial source of pilocarpine is Pilocarpus microphyllus Stapf., known as Marnham jaborandi. Saxitoxin is an extremely toxic neuromuscular blocking agent found in the so-called coastal red tides of North America. Liver damage, carcinogenesis, venoocclusive disease (mammals) glaucoma (rat, mouse) LD ' (mouse) 20 mg kg Sanguinarine mustard oil and cereal grains (contaminated from Argemone mexicana) Expectorant for chronic eczema and skin cancers

Chronic Vesiculoulcerative Disease

CICATRICIAL PEMPHIGOID Cicatricial pemphigoid is a chronic vesiculobullous mucocutaneous disorder with an autoimmune etiology. Autoantibodies against the basement membrane result in subepithelial cleft formation. Cicatricial pemphigoid affects people in the seventh decade of life, with no race predilection. The ratio of males to females 1 2.27. Oral lesions are seen in approximately 85 percent of patients, but any mucosal or cutaneous site can be affected. Oral lesions may begin as a desquamative gingivitis or vesiculobullous lesions. Oral lesions eventually become denuded, leaving a painful, erythematous, irregularly bordered erosion or ulcer. Lesions may persist for weeks. Significantly, ocular involvement occurs in 65 percent of cicatricial pemphigoid patients and, if untreated, may lead to blindness. Referral to an ophthalmologist is essential. Diagnosis is by biopsy and immunofluorescent staining of perilesional mucosa. Histologically, the lesions show inflammatory infiltrates...

Neuropsychology of Object and Face Perception

In addition to using animal models, as described in the last subsection, it is also possible to examine the neurophysiological underpinnings of object perception with the help of humans who have sustained damage to visual areas of their brains. Agnosia is the general term for patients who have lost the ability to visually recognize objects. Such patients retain normal visual acuity and memory they can see objects and remember object labels (as well as their structural and functional properties) but they cannot retrieve an object's name from its image. Even more remarkably, patients with associative forms of agnosia may be able to produce excellent drawings of objects frommemory, but fail to name their own drawings when shown them later.

Recognition of Zinc Deficiency in Developing Countries

The detection of zinc deficiency in populations and the recognition of its association with health outcomes have been somewhat more challenging for zinc than for other nutrients, contributing to the delay in efforts to control it. The ability to diagnose zinc deficiency in individuals using biochemical measures is somewhat limited. For example, the concentration of zinc in serum or plasma may not diminish until the depletion of zinc is more advanced, making it less useful for diagnosing mild to moderate zinc deficiency states in individuals. Other possible biochemical indicators of zinc status have not been consistently demonstrated to reflect change in zinc status. These limitations may have subsequently dampened enthusiasm for evaluating zinc status at the population level. Furthermore, the health conditions that are clearly associated with zinc deficiency (e.g., childhood growth stunting, common childhood infections, and mortality described in further detail below) are general in...

Secondary Causes of Headache

OPHTHALMIC DISORDERS Acute glaucoma may present with headache, and in other eye disorders, such as iritis or optic neuritis, some patients may describe eye or supraciliary pain as headache. These conditions can usually be distinguished by a careful history and eye examination, including measurement of intraocular pressure when necessary.4

Visionsight Theories Of One of

Named after the German physiologist Karl Ewald Hering (1834-1918), states that the muscles of each eye always operate in synchrony because they receive the same innervation the study of responses to light in lower organisms the higher psychological implications of light, color, form, and their temporal and spatial relations (cf., Harvey's principle -when a grating is viewed, the number of vertical stripes per unit of total breath is overestimated and the number of horizontal stripes is underestimated Leonardo's paradox - named after the Italian artist scientist Leonardo da Vinci (1452-1519), refers to da Vinci's assertion that it is not possible to reproduce via a painting what a person sees binocularly, because in binocular vision, each eye sees something that the other eye does not see Hering's law of identical visual direction - in binocular vision, any pair of corresponding lines of direction in objective space are represented by a single line of direction in visual space and the...

Protracted Visual Functions Opening New Doors to Plastic Changes

Though so far we have concentrated on visual functions that have a short and well-defined matura-tional time course, other visual functions, such as visual acuity, long-range orientation integration, or orientation toward peripheral space, seem to have a protracted time course of development and a much longer period of sensitivity to altered visual experience. Grating acuity or the capacity to discriminate sinusoidal gratings from noise is extremely low at birth it develops rapidly during the first 6 months of life, but then continues to improve very slowly until about 6 years of age. Although adultlike performance is achieved around that age, it is not until about 10 years of age that visual acuity is no longer sensitive to altered visual experience. Early visual deprivation such as cataracts or strabismus results in enduring loss of visual acuity. Researchers have shown that tests of visual acuity just after corrective surgery indicate acuity within the range of newborns, even when...

Inhibitors Of Carbonic Anhydrase Pharmacokinetics and Pharmacodynamics

These agents are now most frequently used for glaucoma, but they represent a milestone in the development of diuretics. Modern diuretic therapy was launched when it was noted that sulfanilamide caused a diuresis rich in sodium bicarbonate. Chemical modification of this compound resulted in current carbonic anhydrase inhibitors such as acetazolamide, and subsequently thiazide, and loop diuretics. Little is known of the pharmacokinetics or pharmacodynamics of carbonic anhydrase inhibitors. The only study examining the pharmacokinetics of acetazolamide did so in five healthy volunteers. Peak concentrations occurred in 1 to 3 hr after an oral dose and the elimination half-life averaged 13 hr 14 . This half-life means acetazolamide can be used on a once or twice daily basis with chronic therapy. The most frequent use of acetazolamide as a diuretic is to induce an alkaline diuresis to facilitate renal elimination of drugs such as salicylates or phenobarbital in overdose settings.

Discovery of Highly Potent AChE by In Situ Click Chemistry

Carbonic anhydrases are Zinc-enzymes that catalyze the interconversion of HCO3- and CO2. They are involved in key biological processes related to respiration and the transport of CO2 HCO3, bone resorption, calcification and tumori-genicity 60 . Systemically and topically administered carbonic anhydrase inhibitors have long been used to control the elevated intraocular pressure associated with glaucoma 61, 62 . Most inhibitors are aromatic or heteroaromatic systems that carry a sulfonamide functional group 63-65 , which coordinates the Zn2+ ion in the active site. Based on this information, Kolb et al. designed 4-ethynylbenze-nesulfonamide as an anchor molecule for the target-guided formation of carbonic anhydrase inhibitors (Fig. 15.5) 53 . The benzenesulfonamide anchor molecule was incubated with each of 24 azide reagents in the presence of bovine carbonic anhydrase II for 40 h. Analysis of all 24 reaction mixtures by liquid chromatography with mass spectrometry selected ion mode...

Color Vision Theorieslaws

And yellowish (about 580 nm) and the longer wavelengths as reddish (about 700 nm). The term chromatic refers to stimuli that have all three of these aspects (and have color), whereas the term achromatic refers to stimuli that have only the brightness aspect (and are white-gray-black). Typically, the better theories of color vision can account for several phenomena the primary colors (unique hues) of blue, green, yellow, and red the complementary colors (i.e., any of the colors that are opposite to each other on the color wheel and when additively mixed produce an achromatic gray) and their influence in afterimages and contrast effects the laws of color mixture and the different symptoms of various types of color blindness e.g., pro-tanopes, deuteranopes, tritanopes cf., Horner's law - named after the Swiss ophthalmologist Johann Friedrich Horner (1831-1886), which is the genetic principle that the most common form of color blindness, red-green, is transmitted from male to male through...

Effects of Radiation Exposure on Humans

The Chronic Radiation Syndrome (CRS) was defined as a complex clinical syndrome occurring as a result of the long-term exposure to total radiation doses that regularly exceed the permissible occupational dose by far (2-4 Sv year). Clinical symptoms are diffuse and may include sleep and or appetite disturbances, generalized weakness and easy fatigability, increased excitability, loss of concentration, impaired memory, mood changes, headaches, bone pain, and hot flashes. The severity of delayed effects depends on dose. These delayed effects may include cancer, cataracts, non-malignant skin damage, death of non-regenerative cells tissue, genetic damage, impact on fertility, and suppression of immune functions.

Contact Dermatitis Of The Face

Clinically, allergic contact dermatitis resulting from an aerosolized allergen presents as erythema or scale with or without vesiculation. The involvement is diffuse with upper and lower eyelids affected. This distribution is in contrast with photosensitive eruptions in which nonsun-exposed areas, such as the upper eyelids and the upper lip, are spared. Direct allergic contact dermatitis tends to be most prominent on the most sensitive skin, such as the eyelids. Examples of aerosolized contactants include rhus (poison ivy, oak) when the plant has been burned. Examples of common contactants affecting the face include nickel, nail polishes, toothpaste, preservatives in make-up, contact lens solutions, eyeglasses, and hair care products. Chemical-splash injuries are a common cause of facial-irritant contact dermatitis. A thorough history is necessary to uncover the offending agent. Referral to a dermatologist or allergist may be necessary if the history is unrevealing. Avoiding the...

Clinical Manifestations

In more severe cases, SAH may lead to a decreased level of consciousness and various global and focal neurological deficits may be elicited during physical examination. Ophthalmologic examination may reveal unilateral or bilateral subhyaloid hemorrhages in nearly 25 of patients with SAH. These are venous in origin and are situated between the retina and vitreous membrane.

Toxicants in foods and their effects on nutrition

With the exception of vitamin D, vitamin A, and some minerals, the intake of nutrients from natural food sources will not pose any significant health problems. However, one can argue that the health problems associated with high intakes of protein, fats, or energy are really manifestations of nutrient toxicity, i.e., cardiovascular diseases, cancers, and eye diseases such as macular degeneration and other chronic diseases. The other potential means whereby nutrient intakes can present health problems is the abuse of nutrient supplementation. A nonfood source of a nutrient can produce pharmacological actions at concentrations well above normal dietary amounts.

Effects Of La And Gla Treatment On Diabetic Nerve

A number of investigators have examined the effect of supplementing the diet of the diabetic animals with essential fatty acids, a treatment that might ameliorate the loss of AA. One approach has been to feed large amounts of LA and this has yielded variable results. In several studies, feeding a diet rich in corn oil or sunflower oil, which have a high content of LA but no GLA, failed to improve reduced nerve conduction velocity and nerve blood flow. In contrast, in one investigation corn oil administration was effective in preventing decreased nerve conduction velocity (Kuruvilla et al. 1998). In this study, the administration of LA elevated the proportion of ACMS in the nerve from normal animals, but it did not correct the fall in ACMS in diabetic nerve. Inclusion of LA in the diet was found to largely prevent diabetic cataract formation in rats, despite the persistence of high sorbitol levels in the lens (Hutton et al. 1976). Beneficial effects on diabetic...

Hidden Problems in Stoma Care

Environment is needed where there will be no continual interference, such as a need by others to use the bathroom, the telephone ringing or bleeps going off. Even if the patient has not admitted to a hearing impairment, the nurse should face the patient during teaching and use straightforward sentences as opposed to medical jargon. Although written information may be given, the patient may be unable to read adequately or not at all. If it has been ascertained before teaching the patient that there is an inability to read, written information on appliance changing can be given in picture form, using pictures put together from the various patient teaching booklets. Those patients with visual acuity problems may manage better with enhanced light or may need sunlight reduced if the room is too bright. For those who are blind the use of tapes and Braille cards helps reinforce teaching.

Physical Examination

Extraocular Muscles

The physical examination typically proceeds in a sequential fashion unless the circumstances require otherwise (i.e., chemical ocular injuries require intervention prior to assessment of visual acuity). The glossary of terms and abbreviations below is useful in documenting the findings. The typical eye examination sequence is as follows. VISUAL ACUITY An attempt should be made to obtain an assessment of visual acuity in each eye in all consciously alert patients. Each eye should be tested individually. If the patient uses glasses or contacts but the glasses are not available, pinhole testing can be performed to obtain an estimate of corrected visual acuity. Distance charts are preferable but are not practical with patients confined to a stretcher. Nearsighted patients and those under age 45 can use a near card to test their visual acuity. Patients in their midforties or older may require reading glasses or bifocals to read a near card because of presbyopia. If these patients do not...

Pretectal Complex and the Accessory Optic System

Anterior Pretectal Nucleus Function

Despite the clear connections of the final common pathway, how the superior colliculus directs eye movement control remains unclear. Work in the monkey suggests that the superior colliculus neurons provide monosynaptic connections to the long-lead burst neurons and not the excitatory burst neurons of the PPRF. In fact, most papers suggest that the input to the excitatory burst neurons of the PPRF is polysynaptic and not monosynaptic. The activity of long-lead burst neurons (LLBNs) is not uniform. Instead, a subgroup of LLBNs discharges only for particular directions (e.g., horizontal) of ipsilateral eye movements (directional LLBNs), whereas other LLBNs discharge for eye movements of very specific amplitude regardless of direction (i.e., vector long-lead burst neurons). As a result, one could generate a horizontal eye movement by projections of superior colliculus neurons to a select subgroup of vector LLBNs, which in turn activate the directional LLBNs and subsequently activate the...

Neuromuscular Blockade

There are other, less preventable side effects of succinylcholine. The serum potassium will transiently rise an average of 0.5 meq L with succinylcholine. A clinically significant hyperkalemic response following succinylcholine administration in prescreened ED patients is uncommon. 14 Nevertheless, hyperkalemia may be pronounced hours after muscle trauma or burns. It should not be a factor in the immediate aftermath of such injury. Still, it is advisable to avoid depolarizing agents in patients with burns, muscle trauma, crush injuries, myopathies, rhabdomyolysis, narrow-angle glaucoma, renal failure, or neurologic disorders. Any patient with denervated musculature (e.g., Guillain-Barre syndrome or spinal cord injury) is particularly at risk. Genetically susceptible individuals may develop acute malignant hyperthermia.

Equipotent Enantiomers

Properties for which they are indicated, they may have subtle and sometimes unknown differences. For example, although enantiomers of propranolol have equal potencies in reducing sperm motility, the adrenoceptor property of the drug is attributed mainly to its S enantiomer (4). Hence, as a spermicide, -propranolol may be a safer drug as it reduces sperm motility without much of an effect on the cardiovascular system. A similar scenario has been observed for another -blocker, timolol Both enantiomers appear to be effective in the treatment of open-angle glaucoma (6). However, topical use of the available S-timoloI has been associated with some systemic side-effects such as asthmatic attacks (7). On the other hand, the J enantiomer that only has weak p-blocking activity increases retinal choroidal blood flow that can improve the treatment (8). Therefore, the availability of an optical R-timolol seems to be timely.

Biochemical pathways leading to the synthesis and metabolism of the major neurotransmitters in the mammalian brain

Reversible anticholinesterases which are in clinical use. Both act in similar ways but they differ in terms of their lipophilicity, the former being able to penetrate the blood-brain barrier while the latter cannot. The main clinical use of these drugs is in the treatment of glaucoma and myasthenia gravis.

Cannabis and the cannabinoids

There are two features of the cannabinoids which may ultimately be of therapeutic importance. THC lowers intraocular pressure, which may be of benefit in the treatment of glaucoma. There is also evidence that THC is a moderately effective antiemetic agent. Such a discovery has led to the development of nabilone, a synthetic cannabinoid, as an antiemetic agent, but its use is limited because of the dysphoria, depersonalization, memory disturbance and other effects which are associated with the cannabinoids. Whether the bronchodilator action of THC will ever find therapeutic application in the treatment of asthma remains an open question.

Effects on Particular Organs or Organ Systems

The eye is vulnerable to irritants such as smog, solvents, detergents, and corrosive substances. Other pollutants act systemically and can damage the optic nerve. For example, methanol and carbon disulfide damage the central vision in this way, and pentavalent arsenic and carbon monoxide affect peripheral vision.

Impact Of Dietary Essential Fatty Acids On Neuronal Cell Composition And Function

Animal studies have shown that when rodents or monkeys were maintained on an n-3-deficient diet, electroretinogram abnormalities (Benolken et al., 1973 Bourre et al., 1989b Weisinger et al., 1996a), reduced visual acuity (Neuringer et al., 1984, 1986), altered stereotyped behavior (Reisbick et al., 1994), and decreased level of learning and memory occur (Bourre et al., 1989 Mills et al., 1988 Lamptey & Walker, 1976 Yamamoto et al., 1987, 1988). Dietary n-3 fatty acid deficiency affects brain functions of preterm infants as measured by cortical visual evoked potential, electroretinograms, and behavioral testing of visual acuity (Birch et al., 1992 Carlson et al., 1993a Uauy et al., 1990). Human preterm infants fed infant formulas without 22 6n-3 were also shown to have abnormal electroretinograms, as well as decreased visual acuity compared to infants fed formulas containing 22 6n-3 (Carlson et al., 1993a Uauy et al., 1990). Furthermore, infants fed vegetable oil based formulas with...

Painless Visual Reduction Loss

Cardiac), thrombosis, giant-cell arteritis, vasculitis (lupus), sickle cell disease, and trauma. Often the patient will have atrial fibrillation. The retina will sustain irreversible damage within 90 min of total occlusion, so treatment should begin immediately. Unfortunately these patients rarely respond to therapy, but because the visual loss is usually so profound, every attempt should be made to reestablish circulation to the retina. Treatment in embolic cases (the majority) is aimed at trying to convert a CRAO into a branch retinal artery occlusion (BRAO). In the attempt to dislodge the embolus from the central artery and into one of its retinal branches, the other retinal branches may become reperfused, thereby reducing the size of the infarct. Maneuvers include digital massage, IOP-lowering drugs, and vasodilation techniques (breathing into a paper bag to increase Pa CO2). An ophthalmologist should be consulted immediately to evaluate the patient and decide whether performing...

Epidemiology And Classification Of Dm1

In the classical form, which is the most common, symptoms become evident between the second and the fourth decade of life, showing a slow progression over time (table 36.1). The key feature of the disease is myotonia, which is characterised by delayed relaxation after muscular contraction (fig 36.1A,B) progressive muscular weakness (dystrophy) and wasting are also typical findings facial, axial, semi-distal, and distal compartments are predominantly involved. DM1 is, however, a multisystem disorder indeed, affected patients can manifest abnormalities of other organs and systems including the eye (cataract), the endocrine system (diabetes, thyroid dysfunction, hypogonadism), the central nervous system (cognitive impairment, mental retardation, attention disorders), the gastrointestinal system (dysphagia, constipation, gallbladder stones, pseudoobstruction), and the heart (table 36.2). Minimal DM1 begins later in life, usually after 50 years of age, with a very mild degree of muscle...

Development and Plastic Changes in Orientation Motion and Stereopsis

Early medical conditions in humans such as strabismus or cataracts result in deficits similar to those noted in animal studies. In particular, greater abnormalities in visual functions are noted after monocular congenital cataracts than after bilateral ones. This effect is so potent that it has become normal practice to recommend the patching of the good eye for 50-90 of the time in patients operated for unilateral cataracts to encourage the use of the previously deprived eye. Additionally, visual deprivation has dramatic effects on stereopsis. Children treated for congenital cataracts display little measurable stereopsis, a finding consistent with observations in animal models of a loss of neurons tuned to binocular disparity and a reduction in cells that respond to both eyes after deprivation by lid suture. Interestingly, these individuals (who still have strabismus in adulthood) report deficits of binocular integration and complain of visual suppression or interference between...

Eye Discharge Redness and Conjunctivitis

The neonate with a red eye and irritability may also be suffering from a corneal irritation or abrasion, usually due to an eyelash. Acute glaucoma, although rare, also presents as a red, teary eye. In these instances, the cornea may be stained or cloudy, the anterior chamber shallow, and the intraoccular pressure increased. Prompt opthalmologic referral of all suspected cases of glaucoma is mandatory. Infectious causes should be treated (Iable l12 6) and follow-up care ensured.454 4 and 48

Clinical Features

Tingling Vermilion Border

OCULAR HSV HSV infections of the eye can lead to corneal blindness and are usually caused by HSV. An ulcerative keratitis is the most common manifestation. Herpetic vesicles can be seen on the conjunctiva or on the lid margin as a blepharitis. There is a regional adenopathy. Fluorescein staining may show a diagnostic dendritic ulceration of the cornea. Due to the threat of permanent vision loss, consultation with an ophthalmologist is mandatory and antiviral therapy should be begun immediately. Superficial keratitis usually heals completely in several weeks. Recurrent ocular infections may involve the deeper structures, with a high risk of visual loss, and, if deeper structures are involved, immediate consultation with an ophthalmologist and the administration of IV acyclovir is appropriate. Following the acute treatment, long-term treatment with acyclovir can reduce recurrences of ocular HSV.15 Eye care is important in preventing damage due to impaired blinking and decreased tearing....

Dominatormodulator Theory

DONDERS' LAW AND DONDERS' REACTION-TIME TECHNIQUES. The Dutch physiologist ophthalmologist Franciscus Cornells Donders (1818-1889) formulated this principle of visual fixation in 1846, according to which every position of the lines of regard in relation to the head corresponds to a definite, invariable angle of torsion of the eyes, regardless of the path by which that position has been reached. Another version of Donders' law states that the position of the eyes in looking at an object is independent of the movement of the eyes to that position regardless of previous fixation points, every point on the line corresponds to a definite, invariable angle of the eyes, resulting in the fixation point being focused on the retina's fovea. Aided, in part, by Hermann von Helm-holtz's invention of the ophthalmoscope in 1850, Donders established himself as a specialist in diseases of the eye, setting up a poly-clinic for eye diseases at Utrecht University. Donders improved the efficiency of...

Vitamins Water Soluble Thiamin Riboflavin and B6

Symptoms of riboflavin deficiency include a reduction in growth rate, stiffness of gait, alopecia (hair loss), seborrhea (crusty exudates), vomiting, and cataracts. Other deficiency symptoms that have been observed are increased blood neutrophil granulocytes, reduced immune response, discolored kidney and liver tissue, fatty liver, and degeneration of the myelin of the sciatic and brachial nerves. Females with severe deficiency have also been

Definition and epidemiology of diabetes and impaired glucose tolerance

For many years it was apparent that patients with diabetes had a high risk of developing eye disease, kidney disease, peripheral nerve disease, and cardiovascular disease (that is, coronary heart disease, cerebrovascular disease, and peripheral vascular disease). In 1979 and 1980 it was also recognized that these complications were occurring in patients with both diagnosed diabetes and asymptomatic, undiagnosed diabetes.9 On the basis of epidemiologic studies of the risk of eye and kidney disease according to the 2 hour glucose level (during a 75 g oral glucose tolerance test) in populations at high risk for diabetes, specific glucose thresholds were defined for the diagnosis of diabetes (Table 15.2). These specific levels were those above which patients were at high risk of diabetic retinopathy and nephropathy patients with levels below this threshold had a very low risk for these diabetic complications.7'8'10 The fact that these thresholds were not chosen to reflect the risk of...

Collaboration with the food industry retail and manufacturing

The question of whether allergic customers should be given an extra warning - such as a coloured flash or symbol - has generated much debate. The views of individual customers differ on this, some people wanting a prominent warning about the presence of nuts, others preferring a statement guaranteeing that a product is nut-free. The official view of the Anaphylaxis Campaign - not necessarily shared by every member - is that the prime concern is to get all allergenic ingredients printed in the ingredient list. Although this is sometimes hard on those with poor eyesight, we feel that people should be able to rely on one simple, uniform system of getting information. Coloured flashes or symbols that differ from company to company may only serve to confuse, particularly when these are placed well away from the ingredient list. What may be helpful is an additional statement, CONTAINS NUTS, for example, placed immediately under the ingredient list.

Biochemistry and Physiology of Galactose

The main pathway of galactose metabolism in humans is the conversion of galactose to glucose, without disruption of the carbon skeleton. The name 'galactosemia' has been associated with a syndrome of toxicity associated with the administration of galactose to patients with an inherited disorder of galactose utilization, leading to multiple clinical manifestations, including malnutrition, mental retardation, liver disease, and cataracts. The clinical manifestations are linked to specific enzymatic defects. Thus the term 'galactosemia' should be qualified by the specific defect. Three enzymatic steps are required to metabolize galactose to UDP-glucose. Two alternate pathways, oxidation and reduction, are used in the absence of enzymes of the main route. Patients with classical galactosemia have markedly elevated levels of galactitol in plasma and urine, which remain above age-matched control levels after treatment with galactose-free diet, whereas high urinary galactose levels return to...

Effects of Congenital Deafness on Vision

Studies of visual functions after early genetic deafness indicate enhanced visual processing, at least for visual motion, visual attention, and peripheral vision. For example, deaf adults are better than hearing controls at detecting the onset or the direction of motion of a peripheral stimulus. They are also faster at switching visual attention toward a near-periphery target in the presence of distractors located at the fixation point. Electrophysiological recordings while subjects monitored moving stimuli have indicated larger visually evoked responses for deaf than hearing adults over occipital and temporal sites. These group differences were especially marked for peripheral stimuli. In an fMRI study, the effects of visual attention on motion

Familial Hypoalphalipoproteinemia

Severe HDL deficiency, characterized by HDL cholesterol levels < 10mgdl-1 is rare and may be due to Tangier disease, apo A-I deficiencies, LCAT deficiency, or fish-eye disease. The apo A-1 deficiency states are due to rare deletions, rearrangements, or point mutations within the apo A-I C-III A-IV gene complex. Familial hypoalphalipoproteinemia is relatively common and is characterized by HDL cholesterol levels below the 10th percentile of normal. These subjects have been reported to have either decreased HDL production or increased HDL apo A-I catabolism. This phenotype is present in about 4 of kindred with premature CHD.

Headaches of Ocular Origin

Headache is rarely due to the eye, with the exception of obvious ocular pathology. Photophobia, associated with migraine, is rarely caused by diseases of the eye, eye muscles, or the optic nerves. Reading, eye strain, eye muscle imbalance, or refractive errors are rare causes of headache. The pain of glaucoma is due to an increased intraocular pressure within the globe. The severity is more directly related to the rate of increase of the intraocular pressure rather than the absolute pressure. Glaucoma can be easily classified as (i) open if the anterior angle filtration is patent, (ii) closed if the chamber is blocked, or (iii) combined if the chamber is patent and blocked. The type of glaucoma with the most severe pain is caused by acute closure ofthe angle in the anterior chamber. On exam, the orbit is rock hard'' and immediate ophthalmologic referral is necessary.

Antiaging Interventions Ethical And Social Issues

An estimated 2,500 physicians in the United States had established specialty practices devoted to longevity medicine by 2003, and the American Academy of Anti-Aging Medicine (A4M) boasted 11,000 members in that year. The goal of this clinical community is to extend the time their patients can live without the morbidities of the aging process namely memory loss, muscle loss, visual impairment, slowed gait and speech, wrinkling of the skin, hardening of the arteries, and all the other maladies we call aging (Shelton). At the beginning of the twenty-first century, however, there was little the practitioners of anti-aging medicine could prescribe that had any scientific validation (Olshansky, Hayflick, and Carnes Butler et al.). But the scientists who study the biology of human aging, known as biogerontologists, are slowly making headway, and a central research agenda for this community is to provide clinicians with the tools they require to make anti-aging medicine a reality (Kirkwood...

Orbital Cellulitis Postseptal Cellulitis

Orbital cellulitis is an orbital infection therefore it is deep to the orbital septum. This is a serious ocular infection that has the potential to be life-threatening. Staph. aureus is the most common pathogen however, H. influenzae flu should be considered in young children and mucormycosis in diabetics and immunocompromised patients. Polymicrobial infection is common. Orbital extension of paranasal sinus infection (especially ethmoid sinusitis) is the most frequent source. Orbital and sinus computed tomography (CT) scans should be performed in the ED. If the CT is negative, an enhanced CT should be performed looking for a subperiosteal abscess. Diagnostic clinical findings that help distinguish this infection from preseptal cellulitis include EOM motility impairment, pain, fever, and occasionally proptosis. Decreased visual acuity is a late finding. Cavernous sinus thrombosis can also occur. These patients require a full workup, admission, and intravenous antibiotics.

How the Environment Is Involved in Complex Disease

Genes are not the only things that can affect a complex trait. Often environmental factors can also be involved. The type of environmental factors can be very different for different traits. One obvious example of this is lung cancer. Smoking cigarettes greatly increases the risk of developing lung cancer. Smoking also seems to have an effect on other diseases, including some eye diseases (such as age-related macular degeneration). However, not every chronic smoker will develop lung cancer or eye disease The presence of particular alleles of susceptibility genes is also a risk factor, as discussed below.

Penetrating Trauma Ruptured Globe

Penetrating ocular trauma can occur from numerous sources (BB pellets, lawn mower projectiles, hammering, knife and gunshot wounds). Any projectile injury has the potential for penetrating the eye. Any lid laceration from a sharp object, especially if it involves the upper and lower eyelid has the potential to have lacerated the globe and requires a slit-lamp examination. Clues to a ruptured globe or intraocular foreign body include shallow anterior chamber, hyphema, irregular pupil, significant reduction in preinjury visual acuity, and poor view of the optic nerve and posterior pole on direct ophthalmoscopy. It is not unreasonable to dilate the eye with Mydriacyl 1 and phenylephrine 2.5 to obtain a better view of the posterior segment of the eye, facilitating identification of an intraocular foreign body or retinal detachment. A modified Seidel test is helpful in identifying wound leaks (see Fig. 230-7). Any penetrating injury is considered a ruptured globe and mandates an eye shield...

Micronutrient Deficiency

There is a rising trend toward dietary supplementation with pharmaceutical preparations containing large doses of vitamins and minerals, based on conclusions drawn from the results of several studies. Available evidence derived from human and animal studies indicates that antioxidant micronutrients, mainly vitamins A, C and E, may play a role in boosting immunity, preventing neoplastic disease, and preventing or retarding the progression of several degenerative diseases, such as atherosclerosis. Vitamins E and C have also been shown to reduce low-density lipoprotein (LDL) cholesterol levels and increase high-density lipoprotein (HDL) levels, in addition to lowering fasting plasma insulin levels and improving insulin efficiency. Epidemiological studies have suggested a protective role for antiox-idants such as vitamin C, vitamin E, -carotene, and glutathione in macular degeneration and cataracts. Nevertheless, evidence derived from other epidemiological studies suggests that...

TABLE 2132 Clinical Emergencies in Patients with Sickle Cell Anemia

Bilirubin gallstones are found in up to 75 percent of patients with SCD. Hepatomegaly and liver function test abnormalities are common. Splenomegaly is seen in children with SCD however, by adulthood, the spleen is usually small as a result of recurrent infarction. Renal abnormalities including isosthenuria (inability to concentrate urine) and papillary necrosis occur commonly because of sickling phenomena in the hypertonic, acidic renal medulla. Bony abnormalities, resulting from expansion of the marrow space, and bony infarcts are typical. Radiographs of the bones show thinning of the cortices and sparseness of the trabecular pattern the biconcave fishmouth changes in the vertebrae are pathognomonic of SCD. Skin ulcerations occur over the distal lower extremities. Ophthalmologic problems primarily involving the retinae are common. Chronic disabilities resulting from central nervous system vasoocclusive events are seen.

Glossary Of Terms Abbreviations And Notations

It is important to understand the terms and abbreviations used in ophthalmology, not only to be more effective and precise when interacting with consultants but also to aid you in interpreting their written consultations. CF counting fingers (visual acuity assessment) HM hand motion (visual acuity assessment) PH pinhole visual acuity Ttono Tension (IOP) with subscript representing method used (tono Tonopen, S Schi0tz, A applanation). VAc visual acuity with correction (glasses or contact lenses) VAs visual acuity without correction By convention, in documenting the visual acuity (VA) or IOP, the right eye is listed above the left, as follows

Role of Experience in Development

The role of sensory experience during sensitive periods has been documented in numerous animal studies. Experience in part controls the selection of axons, dendrites, synapses, and neurons that will form the functional neural circuits. For example, during the sensitive period for ocular dominance, visual deprivation induced by monocular eyelid suture results in shrinkage of the ocular dominance columns serving the closed eye. Outside the sensitive period, visual deprivation has little effect on the pattern of ocular dominance. There is good agreement in the literature that experience affects the organization of local circuits rather than major pathways because the main topographical and columnar organization of the cortex has already been achieved by the time most sensitive periods have been reported to occur. Experience has also been implicated in the onset of sensitive periods. In cats, rearing in the dark results in delayed onset of the sensitive period for ocular dominance...

TABLE 1173 Differential Diagnosis of Allergic and Infectious Conjunctivitis

Fluorescein staining always should be performed in an effort to identify the dendritic corneal ulcerations characteristic of herpetic disease. If they are identified, treatment is with acyclovir or other antiviral agents under the supervision of an ophthalmologist. Because N. gonorrhoeae is usually acquired during passage through the birth canal, infants under 1 month of age must always be tested for this pathogen with a Gram stain and culture. If gram-negative intracellular diplococci are seen on smear, a single intramuscular injection of ceftriaxone (125 mg) is indicated.1

Subject Population and Endpoints

In drugs developed for non-life-threatening diseases, a Phase II clinical trial is usually the first one to recruit patients with the disease under study. Patients for Phase II trials are recruited so that these patients may be most likely to benefit from the drug candidate and least likely to be exposed to potential toxicities. Endpoints used in Phase II studies include efficacy and safety endpoints. The efficacy endpoints may be clinical endpoints such as blood pressure, time to disease relapse, number of painful joints, visual acuity or surrogate markers such as white blood cell count, bone mineral density, among others.

Central and Peripheral Nervous System

Special senses The special senses related directly to the cranial nerves (vision, hearing, taste, and smell) experience age-related change. With respect to vision, the most typical of all biological aging changes is presbyopia, or the loss of accommodation function for the ocular lens with loss of capacity of the associated musculature. The consequence is loss of near-vision, which leads to the need for reading glasses or bifocal spectacles. A more important aging change related to the lens is the opacification that leads to cataract formation. The eye is designed to translate light energy into visual images, but the energy of light, particularly the ultraviolet fi rays of solar energy, damages ocular tissue. Thus, there is as a strong environmental component to the disarranging of the laminar stacking of the fibrillar proteins of the lens, which imparts its clear, transparent basis consumption of diets high in antioxidant vitamins has been associated with the delay in cataract...

Clinical Description Dm1

Ninety percent of DM1 patients present at adulthood with delayed muscle maturation, distal muscle weakness, wasting, myotonia, cataracts, cardiac abnormalities, smooth muscle dysfunction, insulin resistance, daytime sleepiness, testicular atrophy (low reproductive fitness), ''difficult'' personality, neuropsychiatric disturbances, and frontal balding. 1 Ten percent of the patients present at infancy with hypotonia (floppy infant), oromotor dysfunction, tent-shaped mouth, feeding and respiratory insufficiency (diaphragmatic hypoplasia), arthrogryposis, and mental retardation in those who survive until adulthood (congenital DM). 1 All manifestations show a progressive course. Usually, creatine kinase is elevated. Muscle biopsy shows type 1 predominance, centrally located nuclei, severe fiber atrophy with nuclear clumps, hypertrophic and angulated fibers, and occasionally, necrotic fibers, fibrosis, or fat deposits. Cardiac involvement comprises conduction defects (mostly HV...

Abusive Blunt Trauma to the Eyes

In my experience, I have found it extremely important to look for indications of direct blunt trauma to the eyes in dead children, even though such direct blunt traumatic injuries are extremely unlikely to have caused the death of the infant. The ophthalmology and or pathology of accidental blunt injuries to the eyes is well known, but such injuries can also be caused by nonaccidental (deliberate) trauma to the eyes. If the ophthalmic pathologist finds severe injuries attributable to blunt trauma in one eye, the injuries could be explained by accidental blunt trauma to that eye. However, if such severe injuries are found in both eyes, then simultaneous (or consecutive) severe injuries to both eyes are extremely unlikely to be accidental (as the eyes point in different directions, and they are protected by being sunk in the orbits) and are extremely likely to be deliberate. In a dead child, these findings are extremely important medicolegally, either with or without another...

Motor Vehicle Crashes

Motor vehicle-related injuries rank as the leading mechanism of injury that brings elderly patients to a trauma center in the United States. Motor vehicle crashes are the most common mechanism for fatal incidents in elderly persons through 80 years of age.1 Emergency physicians should anticipate an increase in motor vehicle trauma involving the elderly due to the growth in this subset of the population and the increase in elderly drivers and occupants. Recent data by Li and colleagues 5 have shown that the crash fatality rate among the elderly is considerably higher than for younger age groups. As noted earlier, similar effects of acute and chronic medical conditions can influence the incidence of motor vehicle crashes. The patient may have decreased cerebral and motor skills and may have memory and judgment losses that can compound the difficulty in operating a motor vehicle. The patient also may have decreased auditory or visual acuity that makes it more difficult to recognize...

Measuring consciousness

Other techniques to present stimuli nonconsciously do exist, such as parafoveal presentation (presenting items in peripheral vision) or dichotic listening (ignoring a message played to one ear while listening to the message played to the other ear). However these rely on directing the focus of a subject's attention away from the stimulus whose processing is being indirectly tested. It is therefore always difficult to entirely rule out momentary switches of attention to the supposedly unattended stimuli. In contrast, a well masked stimulus is hidden from a subject however hard they try to perceive it.

Symptomatic Treatments Of Dystonias

Side effects of anticholinergic drugs are central and peripheral. Central effects include confusion, memory impairment, hallucinations, restlessness, insomnia, nightmares, and sedation. Peripheral side effects (such as dry mouth, blurred vision, exacerbation of acute angle glaucoma, urinary retention, and constipation) may be controlled by peripheral cholinergic drugs, such as pyridostigmine or pilocarpine. Side effects

Step 4 Determine Whether No or Low Cost Alternatives Are Available

Funding sources are often determined by the age of the individual consumer (school system), level of income, relationship to certain state agencies (aging, rehabilitation, deaf and hard of hearing, visual impairment, etc.). Private or public insurance are considerations but primarily for purchase of medically related equipment, which often excludes assistive technologies such as computers, software, memory devices, etc.

Differential Diagnosis

The differential diagnosis of the red (or pink) eye includes conjunctivitis, orbital periorbital infection, foreign body, corneal abrasion, uveitis, and glaucoma. Periorbital and orbital infections cause obvious swelling and tenderness around the eye and or loss of ocular mobility. Foreign bodies should be visible on direct examination, often only following eversion of the upper eyelid. Thus the differential diagnosis usually revolves around four conditions conjunctivitis, corneal abrasion, uveitis, and glaucoma (Table HZ-2). Both uveitis and glaucoma are uncommon. The erythema in these conditions is concentrated around the limbus, and the discharge consists primarily of tears. Additionally, the vision is decreased in glaucoma, and the cornea may be cloudy. A corneal abrasion is easily identified by the uptake of fluorescein. Conjunctivitis is generally self-limited, with the notable exceptions of herpes simplex and N. gonorrhoeae. The potential complications are corneal ulceration...

What does Oxidant Stress Cause

Oxidant stress, through its effects on key biological sites and structures, is implicated in chronic noncommunicable diseases such as coronary heart disease, cancer, cataract, dementia, and stroke (Figure 4). Oxidant stress is also thought to be a key player in the aging process itself. A cause-and-effect relationship between oxidant stress and aging and disease has not been confirmed, however, and it is very unlikely that oxidant stress is the sole cause of aging and chronic degenerative disease. Nonetheless, there is evidence that oxidant stress contributes substantially to age-related physiological decline and pathological changes. Consequently, if it is accepted that oxidant stress is associated with aging and degenerative disease, then opposing oxidant stress by increasing antiox-idant defense offers a potentially effective means of delaying the deleterious effects of aging, decreasing the risk of chronic disease, and achieving functional longevity. For this reason, there has...

Cerebral Achromatopsia

There are rare exceptions-to the tolerance of color discrimination despite large losses in acuity. An occasional subject loses color vision but maintains normal visual acuity after acquired damage of visual cortex. The cases that have been studied most completely with the entire gamut of color testing methods confirm major but not complete loss of color discrimination. They appear to be able to use wavelength

Control of Blood Glucose Level

Irrefutable evidence exists that better control of blood glucose concentration reduces the risk of developing long-term complications from diabetes. This is especially true of microvascular complications such as retinopathy (eye disease), nephropathy (kidney disease), and nerve damage in both type 1 and type 2 diabetes. Control of blood glucose also reduces the risk of macrovascular disease (heart disease, stroke, and peripheral vascular disease), although the contribution of blood glucose to these complications is less strong.

Application B the disease array for a genetically heterogeneous disorder LCA

Leber congenital amaurosis was named after the German ophthalmologist Theodor von Leber who in 1869 first described severe visual loss present at birth accompanied by nystagmus, sluggish pupillary reaction and pigmentary retinopathy. A detailed description of LCA-defining clinical signs has been extensively presented in many reviews albeit a severe and early-onset disease, LCA nevertheless presents with variable expression, which can be sometimes explained by molecular genetic findings (see below). Difficulties with the clinical classification of LCA cases were most prominently demonstrated in a study where 30 out of 75 patients had been initially misdiagnosed (25). All the above further emphasizes the importance of a comprehensive molecular genetic analysis in addition to a thorough clinical evaluation.

Natural Infections

Although infection may be asymptomatic, symptomatic disease typically follows a predictable course. Clinical signs at the onset of disease in horses and sheep are nonspecific excited or depressed behavior, hyper-thermia, anorexia, jaundice, constipation, and colic. Classical disease becomes apparent within 1 or 2 weeks. Animals maintain an upright, wide-based stance with their heads extended. Repetitive behaviors are common and may include vacuous chewing, circular ambulation, and running into obstacles. Horses become paretic in the terminal phases of disease. A distinctive decubitus posture associated with paddling movements of the legs has been described. Frequently, in late disease, the virus migrates centrifugally along the optic nerve to cause retinopathy and visual impairment. Acute mortality may be as high as 80-100 in horses and 50 in sheep. Sheep that survive may have permanent neurologic deficits. Recurrence of acute disease has been described in sheep. Natural symptomatic...

Emergency Department Treatment

Once the primary survey is completed, a careful head-to-toe examination should be performed to identify occult injuries. The cutaneous examination may disclose burns and may help determine the path of the current and locate potential organ injuries. Care for a superficial lightning burn includes cleansing, debridement, application of a topical antimicrobial agent, and administration of tetanus prophylaxis, if indicated. Fasciotomy is rarely indicated, since circulatory disorders are frequently consequences of vasospasm and resolve spontaneously. A careful neurologic examination should be performed to detect motor and sensory deficits. Ophthalmologic (including slit-lamp examination) and otologic examinations should be done to rule out visual and hearing disturbances, as well as tympanic membrane rupture. Abdominal distention due to ileus should be treated with gastric decompression. An acute abdomen may be due to blunt injury and intraperitoneal injury.

External Examination

Cherry-red discoloration is variably observed in the clinical setting, which reflects the observer's visual acuity and experience, and the fact that lower COHb concentrations are usually encountered (461,471,481,500). Cyanosis is more likely (461, 532). Congestion of deeper vessels by COHb causes the skin to appear cyanotic (539). An individual in a cold environment who succumbs to CO vasoconstricts superficial skin vessels, resulting in sequestration of CO-saturated blood in deeper tissues (540). At the scene, failure to examine the entire body and poor lighting means missing the diagnosis (490). The characteristic red lividity of CO poisoning is usually associated with a COHb level greater than 30 however, some cases with a COHb level up to 80 do not show this finding (17,533,540). One study showed that about 98 of unintentional CO-related deaths had typical lividity (533). Three victims without red livor had COHb levels of 18, 28, and 31 , respectively. Coroners recognized only 61...

Ethical Considerations

Whenever the removal of tissues is likely to alter the facial appearance of the deceased, specific signed consent from relatives or consent from the coroner or equivalent authority must be obtained for any procedure, and ethically the reasons for the procedure must be sufficiently important to warrant the possibility of further distress to relatives. Arrangements may be necessary to ensure that the body is only viewed by the relatives before the procedure. Removal of tissues to this extent must be viewed as most exceptional, and discussions with the coroner or local ethical committee may be advisable before relatives are consulted or informed. Under such circumstances it probably is advisable for a senior ophthalmologist (possibly accompanied by a senior pathologist) to explain the circumstances to the relatives to ensure truly informed consent. It must always be assumed that a close relative will view the body after the autopsy procedure has been performed, unless specific...

Selection of Dietary Assessment Measure

A third important objective of dietary survey data is to gain a better understanding of the correlates of nutrient intake, but with respect to individual characteristics that may be associated with lower versus higher intake and the extent to which intake is associated with indicators of health. For many nutrients, the day-to-day variation in intake is considerable, and multiple days would be required to achieve stable estimates of intake at the individual level. Without this, the misclassification of individuals in the distribution leads to a weakening in the ability to see associations that may truly be there. An extreme example is vitamin A, which tends to be concentrated in a few foods. If one frequently has liver and carrots, but happened not to on the day of the recall, that individual would be classified as having low vitamin A intake when their usual intake is quite large. Conversely, one who almost never eats these foods, but happened to have liver on the day of the recall...

Organisms S aureus S epidermidis Conjunctivitis Adult and Children Notes

If conjunctivitis is secondary to an imbedded organic material (mascara brush, tree branch), or in contact lens wearers, consider antipseudomonal coverage. 4. Slit lamp exam important to rule out herpes as organism. If herpes or gonococcus suspected, immediate ophthalmologic consultation is indicated.

Diabetes And Endocrine Disorders

Diabetes mellitus is one of the most common metabolic diseases encountered. The prevalence of diabetes mellitus in both adults and children has been steadily rising in the past 20-30 years. Improved glycemic control has a beneficial effect on microvascular and neuropathic complications in type 2 diabetes, but has no effect on the incidence of macrovascular disease. However, light control of blood pressure (with an ACE inhibitor or a beta-blocker) in patients with type 2 diabetes and hypertension reduces the risk of diabetes-related death, including that secondary to macrovascular complications, as well as the risk of other diabetes-related complications and eye disease.10 Good control of diabetes also decreases the potential for postoperative infection. Diabetic patients need careful treatment with adjusted doses or infusions of short-acting insulin based on frequent blood sugar determinations.

Disorders of Galactose Metabolism Clinical Manifestations

Classically, the term 'galactosemia' was associated with an inherited disorder of galactose utilization characterized by malnutrition, liver disease, cataracts, and mental retardation, resulting from the specific deficiency of galactose-1-phosphate uridyl-transferase. However, other enzymatic defects with variations of clinical presentation can also lead to galactosemia (Table 1). Thus it is preferably better to refer to these abnormalities of metabolism by the specific enzymatic deficiencies which are described below. Cataracts symptoms Cataracts Cataracts have been observed within a few days of birth. These may be found only on slit-lamp examination and can be missed with an ophthalmoscope, since they consist of punctate lesions in the fetal lens nucleus. Several hypotheses have been postulated to account for their formation and are mentioned above. It seems conclusive that the initiator of the process in rats is galactitol and not galactose 1-phosphate. Galactose 1-phosphate...

Betweenmodality Plasticity

Whereas anecdotal evidence of better audition after early blindness or better vision after early deafness exists, the available data are quite mixed. The longheld belief that multisensory integration is a necessary step in optimal development led investigators to focus initially on the disabilities caused by early blindness or deafness. For example, a number of studies, mostly from the 1970s and the early 1980s, document deficient spatial abilities in the blind and deficient visual perception in the deaf. The realization of the adaptability of the brain led investigators to carefully review this issue. It is now evident that when the etiology and characteristics of the population tested are carefully controlled and the task is appropriately chosen not to rely on encoding strategies that are not available to the deprived subjects, convincing evidence of compensatory plasticity can be established.

The Oculomotor System

The oculomotor system is comprised of the intrinsic and extrinsic muscles of the eye along with motor nuclei and higher cortical centers that serve to control the position of the eye as well as the shape of the lens and the size of the pupil. The main purpose of the system is to aid in vision by keeping the visual target focused on the fovea, the area ofcentral retina that has the highest visual acuity. Diplopia (double vision), blurred vision, or loss of depth perception can occur as a result of lesions at various points within the neuronal pathways that subserve the oculomotor system. The pathways are generally well defined and well known, so that it is possible to determine the location of a lesion in the oculomotor system by careful analysis of the types of visual deficits expressed and by direct observation of eye position and reflex eye movements. Tests of oculomotor function are an important part of most physical examinations of patients.

Legal and Ethical Background to Ophthalmic Autopsy Practice Legal Considerations

In an autopsy performed by the coroner or equivalent authority, when the eyes are required for diagnostic purposes (e.g., in suspected cases of nonaccidental injury in infants) or to determine the possible contribution of suspected eye disease to the cause of death (e.g., retinitis pigmentosa or diabetic retinopathy in a road traffic accident). Again, the coroner and pathologist should have a policy on the eventual treatment of the eye tissues that reflects the Royal College of Pathologists guidelines for the retention of tissues and organs at post-mortem examination.48 3. From patients who have donated their eyes for corneal transplantation. These eyes usually are removed by ophthalmologists after arrangement through eye banks, and pathologists are rarely involved. Specific authorization must be confirmed before the eyes are removed.

Clinical Description

Individuals with NF1 are at increased risk for malignant neoplasms. 8 The most common is optic glioma, affecting approximately 15 . 9 Most of these tumors are asymptomatic, but progressive growths can impair vision or cause neuroendocrine disturbance. Gliomas can occur elsewhere in the brain, especially the brainstem. Malignant peripheral nerve sheath tumors are sarcoma-like lesions that arise from neurofibromas (usually plexiform neurofibromas), with a lifetime risk around 10 . Other malignancies that are associated with NF1 include juvenile myelomonocytic leukemia and rhabdomyosarcoma.

Was the assessment of outcomes appropriate

Comparing an agent with a long duration of action to one with a short duration can also be challenging. Timolol eye drops are a standard treatment for managing glaucoma. The maximum reduction in intraocular pressure (IOP) occurs after 1-2 hours and then wears off rapidly. Hence, multiple daily applications are required. In contrast, latanoprost is a prostaglandin analog with

Complicating Effects of Radiation

The embryo has developed into a fetus at about the seventh to eighth week, and neurologic development occurs during the next 7 weeks. Significant x-ray exposure at this time (between weeks 8 and 15) may result in mental retardation, small head size, and decreased IQ. Other possible but less likely effects due to significant exposure during this period include growth retardation as an adult and sterility. Even less likely but still possible are cataracts, neuropathology, and growth retardation at term. Most of the deterministic effects mentioned above are either not observed or observed much less frequently when the fetus receives significant radiation dose beyond 15 weeks postconception. Mental retardation has been observed as a result of significant exposure during the eighth to twenty-fifth weeks but not beyond. Other effects that have been observed because of exposure after week 15 include sterility and growth retardation as an adult. Less likely effects that have been demonstrated...

Figure SC12 Complications

Patients with diabetes may present for incidental surgery or for surgery related to their diabetes, particularly abscesses, wound debridement, amputation of toes, feet or limbs, and cataract surgery, although diabetic patients do not have a higher incidence of cataracts, simply an earlier presentation of the condition. Whether the surgery is incidental or not, and whether the diabetes is insulin or non insulin dependent, there is an interaction between the surgical insult and the diabetes that needs to be properly managed to maintain stability and avoid further complications of both the diabetes and the surgery. Inadequately managed diabetes can result in hyper- or hypoglycaemia, ketoacidosis, wound infection and delayed healing. Occasionally the surgical condition can result in instability and toxic confusion, which will, of course, make the diabetes more unstable and worsen the surgical condition. Patients should not be presented for anaesthesia unless their diabetes is under...

Acanthamoebic keratitis

Improper contact lens wear and care are the most important risk factors. The condition is easily confused with herpes keratitis and if not properly diagnosed and treated, blindness is a common outcome. Patients usually present with severe eye pain and photophobia. The classical finding is a ring infiltrate in the cornea and the symptoms are usually much greater than the signs. Since Acanthamoeba is a neurotrophic organism, the presence of enlarged and prominent corneal nerves is an important clue to this condition. Treatment is difficult and requires prolonged use of relatively toxic medications like neosporin, dibromopropamidine, propamidine, polyhexamethylene biguanide and chlorhexidine.

Adlers Theory Of Personality

The Austrian psychoanalyst Alfred Adler (1870-1937) received his medical degree in 1895 from the University of Vienna with a specialty in ophthalmology but then changed to psychiatry after practicing in general medicine. Adler was one of the charter members of the Vienna Psychoanalytic Society, serving as its president in 1910, but resigned from the society in 1911 because of theoretical differences with Sigmund Freud. Adler went on to establish his own school, called the Society for Free Psychoanalytic Research (later called the Society of Individual Psychology) which attracted followers throughout the world and inspired, also, the establishment of an experimental school in Vienna that employed his theories of education. Adler's theoretical approach to personality generally emphasized the concepts of goal striving, unity, and active participation of the individual and stressed the cognitive rather than the unconscious processes of personality. Adler's theory of personality is an...

Parametersetting Theory

PARANORMAL PHENOMENA THEORY. extra-sensory perception parapsychology psi phenomena. The paranormal class of effects refers to supernatural events results (beyond the normal) that are inexplicable by the usual laws of science and or reason. The related terms extra-sensory perception (ESP) (including clairvoyance, precognition, and telepathy) and psychokinesis (PK) are generic terms for various hypothetical paranormal phenomena that involve experiences having no direct sensory contact, or refer to perception without the use of sense organs (cf., concordant twin theory - the proposition that identical twins will be able to communicate via ESP to a higher degree than concordant twins, and that - even if separated either at birth or soon after - such twins in the future will have similar preferences and lifestyles as well as identical physical ailments). The American parapsychologist Joseph B. Rhine (1895-1980) claimed to have coined the term extra-sensory perception in 1934, but the...