Eye Conditions and Implications

Keratoconus

The cornea becomes cone shaped. Can be found with retinitis pigmentosa, Down's syndrome, Marfan's syndrome, and aniridia. Seems to be congenital and bilateral. Usually has onset in young adulthood - Decreased distance vision, astigmatism, sensitivity to glare, distortion of entire visual field, possible corneal rupture, and can lead to blindness - ADAPTATIONS: Contact lenses are used to retard the bulging of the cornea in the early stages. Good contrast and lighting; avoid glare - CONSIDERATIONS: Avoid activities that could cause corneal damage such as contact sports and swimming in heavily chlorinated water.

Strabismus

The inability of both eyes to look directly at an object at the same time, a muscle imbalance, often secondary to other visual impairments - Affects binocular vision depth perception and eye-hand coordination. There are different types of stabismus: esophoria - a tendency for one or both eyes to turn inward, esotropia or crossed eyes - an inward deviation of one eye in relation to the other, exophoria - a tendency for one or both eyes to turn outward, exotropia or walled eyes - an outward deviation of one eye in relation to the other, hypertropia - a tendency for one or both eyes to turn upward, hyperopheria - a deviation of one eye to turn upward, hypophoria - a tendency for one or both eyes to turn downward, and hypotropia - a tendency for one eye to turn downard lower than the other. May cuase eyestrain and difficulty following fast moving objects, tracking, fixating, and scanning - ADAPTATIONS: Prismatic glasses, eccentric viewing some students may use one eye for distance tasks and one eye for near tasks. - CONSIDERATIONS: Close work may result in loss of place, eyestrain, blurring of print, poor concentration. Frequent rest periods may be needed when doing close work. Students may have difficulties in physical activities and may need more time to adjust to unfamiliar visual tasks. Classroom searing should favor the student's stronger eye.

Dislocated Lens

The lens is not in its natural position - blurred vision, diplopia, cataracts - ADAPTATIONS: Good contrast and lighting - CONSIDERATIONS: Close work may result in loss of place, eye fatigue, blurring of print, poor concentration. Frequent rest periods may be needed when doing close work.

Coloboma

A birth defect which causes a notch or cleft in the pupil, iris, ciliary body, lens, retina, choroid or optic nerve. A keyhole pupil often occurs - decreased acuity, photophobia, nystagmus strabismus; field loss occurs if it extends to the retina. Cataracts, refractive errors, and problems with depth perception may occur. Glaucoma can develop in later life - ADAPTATIONS: Magnification, average or bright light with no glare, cosmetic contact lenses which crease an artificial pupil, telescopes for distance viewing, sunglasses and eyeshades if the coloboma is in the iris - CONSIDERATIONS: High contrast line markers or templates may be helpful for reading , finding math problems, or locating other important info.

Retinopathy of Prematurity (Retrolental fibroplasia)

A curtailment of retinal blood vessel development in premature infacnts which can lead to bleeding, scarring, and retinal detachment. Can range from minimal damage to complete blindness - Decreased visual acuity, severe myopia, possible retinal detachment, spotty vision strabismus, retinal scarring, field loss, possible glaucoma - ADAPTATIONS: High illumination, magnification for close work, telescopes for distance viewing, CCTV - CONSIDERATIONS: Students may have brain damage resulting in behavior problems and/or developmental delays. Precautions should be taken to prevent retinal detachment. Early intervention and sensory stimulation are important.

Diplopia

A defect in the muscules restricting the eyes ability to work together cuasing double vision. The image from one eye is imposed on the image from the other eye. If left untreated it can develop into amblyopia - visual confuction or double vision, dizziness, can result in monocular vision or amblyopia - ADAPTATIONS: good contrast and glare reduction, more time to adjust to new situations. Corrective lenses may be helpful - CONSIDERATIONS: Close work may result in loss of place, eye gatigue, blurring of print, poor concentration and headaches. Frequent rest periods may be needed when doing close work. Familiarization with the environment can ease the awkwardness and help to anticipate distances and heights.

Leber's Congenital Amaurosis

A form of retinitis pigmentosa causing degeneration of the macula occuring at or shortly after birth; progressive central field loss; abnormal corneas and cataracts may be present - Central and peripheral vision can be affected; loss of color vision and detail, nystagmus is present. Excessive rubbing of eyes is characteristic - ADAPTATIONS: Eccentric viewing using peripheral vision, magnification to enlarge the image beyond the scotoma, enlargement of materials or bringing materials closer to the eye, diffused less intense light may permit the eyes to enlarge the pupil so more area can be viewed, telescopes for distance vision, tinted glasses, sunglasses and eyeshades, CCTV with reversed polarity, adjustable lighting without glare - CONSIDERATIONS: High contrast line markers or templates may be helpful for reading, finding math problems, or locating other important info. Teachers should not stand in front of a window or light source when teaching or speaking to the student. Lights with rheostats and adjustable arms are helpful for close work. Fatigue an become a problem.

Retinoblastoma

A malignancy of the retina in early childhood which usually requires enucleation and can occur in one or both eyes - If one eye is removed, there is no depth perception. If the remaining eye is impaired, the condition is more serious. The first sign of the disease may be strabismus - ADAPTATIONS: Prosthetic eyes - CONSIDERATIONS: The absence of depth perception may result in inaccurate reach, and difficulty with steps and drop-offs. Students may have good spatial awareness due to early vision. Many have congnitive and academic abilities at the high and low extremems.

Scotoma

A portion of the visual field that is blind or partially blind - Affects central vision, photophobia, poor color vision, normal peripheral vision - ADAPTATIONS: Eccentric viewing, magnification to enlarge the image beyond the scotoma, enlargement of materials or bringing materials closer to the eye, diffused less intense light may permit the eyes to enlarge the pupil so more area can be viewed, telescopes for distance vision, tinted glasses, sunglasses and eyeshades, CCTV with reversed polarity, adjustable lighting without glare - CONSIDERATIONS: High contrast line markers or templates may be helpful for reading, finding math problems, or locating other important info.

Leber's Optic Atrophy

A rare disease characterized by rapidly progressive optic atrophy which occurs in young men and rarely in women and may include other types of central nervous system involvement - Reduced central activity, fluctuating visual performance, blurred vision, color vision may be impaired; visual perception may be impaired - ADAPTATIONS: High illumination, enlarged print, magnification, high contrast - CONSIDERATIONS: Avoid visual clutter; images should be simple and presented in isolation. When teaching avoid standing in front of a busy background and wearing busy patterns. Modify expectations to accommodate fluctuating visual performance.

Papilledemia

A swelling of the optic disc caused by pressure in the skill; optic atrophy may occur - The blind spot is enlarged, but visual field and visual acuity are otherwise normal. If optic atrophy occurs, slight to total loss of vision can result - ADAPTATIONS: If optic atrophy occurs, high illumination enlarged print, magnification, high contrast - CONSIDERATIONS: If optic atrphy occurs, avoid visual clutter; images hsould be simple and presented in isolation. When teaching, avoid standing in front of a busy background and wearing busy patterns. Modify expectations to accommodate fluctuating visual performance.

Retinal dysplasia

Abnormal growth or development of the retina - Field loss, blurred vision, scotomas or blind spots, possibly loss of central vision - ADAPTATIONS: Magnification for close work, telescopes for distance viewing, eccentric viewing, high illumination, eliminate glare - CONSIDERATIONS: If field loss occurs, physical activities and mobility may be restricted by low light situations such as bad weather or night time. Teach organized search patterns using a grid pattern to aid the student in locating objects or visual targets. Students may need to be seated farther away to increase their visual field. If loss of central central vision occurs, teachers should not stand in front of a widow or light source when teaching or speaking to the student. Lights with rheostats and flexible arms may be helpful for close work.

Phthisis bulbi

Abnormally low pressure of the eye which can cause shrinkage of the eye - May lead to total malfunction of the eye - ADAPTATIONS: Average or bright light with no glare, good contrast; may need magnification - CONSIDERATIONS: High contrast line markers or templates may be helpful for reading., finding math proglems, or locating other important info. If blindness occurs, tatual and auditory modes will need to be developed.

Anophthalmos, Anophthalmia

Absence of one or both eyeballs - total blindness, if both eyes are affected - ADAPTATIONS: prosthetic eyes - CONSIDERATIONS: if both eyes affected, tactual and auditory modes will be used

Aphakia

Absence of the the lens, usually caused when lens is surgically removed due to cataracts - inability to accommodate, may have depth perception problems, or peripheral field distortions - ADAPTATIONS: contact lenses, good contrast and lighting, magnifications, enlargement or bringing items closer to eyes - CONSIDERATIONS: lights with adjustable arms for close work, sunvisors

Glaucoma

An eye disease which causes increased pressure in the eye because of blockage in the normal flow of the fluid in the aqueous humor - May cause fluctuating visual functioning, peripheral field loss, poor night vision, photophobia, difficulty reading or seeing large objects at close range, decreased sensitivity to contrast, pain or headaches, eye redness, hazy cornea, wide open pupil. Can lead to degeneration of the optic disc and blindness if untreated - ADAPTATIONS: Sunglasses and eyeshades, lamps with rheostats or adjustable lighting to provide good quality lighting with no glare, good contrast, magnifiers, CCTV, absorptive lenses - CONSIDERATIONS: Fluctuations in visual performance can be frustrating to the student. Expectations may need to be adjusted accordingly. Stress and fatigue have a negative effect on visual performance. Teachers should be alert to symptoms of pain and increased pressure. If medication is prescribed, it should be taken regularly. Travel in unfamiliar places may be difficult.

Conjunctivitis

An inflammation of the conjunctiva, most common eye disease of the western hemisphere, cuasing red, painful, irritated eyes, tearing and discharge - photophobia may cause corneal ulcers and scarring, ptosis, refractive errors, and can lead to blindness in some cases - ADAPTATIONS: Lighting should come from behind the student and glare should be avoided - CONSIDERATIONS: Rest periods may be needed when doing close work. Time may be needed to adjust to different lighting situations

Corneal Ulcers

An open sore or scarring on the cornea - can appear on any part of the cornea with resulting impairment, blurred vision, reduced central acuity and can lean to blindness - ADAPTATIONS: Eccentric viewing, good lighting and contrast, magnification - CONSIDERATIONS: Lights with rheostats and adjustable arms are helpful for close work.

Enucleation

Anterior chamber of the entire globe of the eye is surgically removed from the orbit - If one eye is removed, there is no depth perception. If remaining eye is impaired, the condition is more serious - ADAPTATIONS: Prosthetic eyes. If one eye remains, good contrast and reduction of glare may help. More time may be needed to adjust to new situations - CONSIDERATIONS: Lack of depth perception may result in inaccurate reach, and difficulty with steps and drop-offs. Familiarization with the environment can ease awkwardness and help to anticipate distances and heights. Classroom seating should favor the student's functional eye.

Hemianopia

Blindness or impaired vision in one half of the visual field - General good acuity with loss of vision in affected portion of visual field. Can occur in one or both eyes - ADAPTATIONS: Fresnel prisms - CONSIDERATIONS: Reading can be difficult. When the student experiences damage to the left field, the left side of the page may not be seen and the student reads from the middle of the page to the end and back to the middle of the page. With damage to the right field, the student may only read from the beginning of the page to the middle, omitting the right side of the page. Reading is more difficult for people with a right field loss. Markers can be used to mark the beginning andend of the line. Reading speed is significantly reduced and students have difficulty finding info on a page.

Diabetic Retinopathy

Both juvenile onset and maturity onset diabetes can cause changes in the blood vessels of the retina, causing hemorrhaging in the retina and vitreous, sensory loss in the feet and hands, and possible retinal detachment and blindness - sensitivity to glare, double vision, lack of accommodation, fluctuating acuity, diminished color vision, defective visual fields, floating obstructions in the vitreous, retinal detachment. If hemorrhages recur, vision may fluctuate - ADAPTATIONS: good lighting and contrast, megnification, closed circuit television - CONSIDERATIONS: Stree and pressure to perform can negatively affect stabilization of blood glucose. Tactual sensation is often poor and reflexes can be slow. Diet can influence attentiveness. Student with advanced sensory loss in their hands and feet may not be able to read braille and may not sense drop offs.

Achromotopsia

Color deficiency or color blindness, cone malformation, macular deficiency - difficulty/inability to see colors and detail, decreased acuity, nystagmus, central field loss - ADAPTATIONS: high contrast, tinted lenses, sunglasses - CONSIDERATIONS: avoid activities dependent on color discrimination, alternative techniques for interpreting color

Rod Monochromacy (Achromatopsia)

Cones are absent or abnormal resulting in the absence of color vision - Poor visual acuity but near vision is usually better than distance vision. Nystagmus and photophbia imporve with age. Colors are seen as shades of gray - ADAPTATIONS: Tinted lenses, reduced lighting - CONSIDERATIONS: Student will not be able to perceive colors but may learn to make color judgements based on brightness. Alternative techniques for interpreting co,or will need to be taught (e.g. the position of the red and green lights in a traffic signal, using color identification tags on clothing).

Microphthalmos, Microphthalmia

Congenital birth defect that causes one or both eyes to be abnormally small. May occur with other congenital abnormalities such as club foot, additional fingers or toes, webbed fingers or toes, polycystic kidneys, and cystic liver - Decreased visual acuity, photophobia, may have fluctuating visual abilities. May result in cataracts, glaucoma, aniridia, and coloboma - ADAPTATIONS: Average or bright light with no glare, good contrast, may need magnification - CONSIDERATIONS: Fluctuations in visual performance can be frustrating to the student and expectations may need to be adjusted accordingly. Be alert for stress and fatigue.

Optic Nerve Hypoplasia

Congenital nonprogressive anomaly in which the optic nerve head appears small and grey or pale and is often surrounded by a mottled yellow halo bordered by a dark ring of pigment, called the double ring sign. There is often indication of abnormalities of the midline structures of the visual system, such as the corpus callosum, causing mid-line deficiencies. There is often a dramatic asymmetry between the two optic heads. Central nervous system and endocrine anomalies, cerebal palsy and mental retardation can also occur - Decreased visual acuity which may vary from light perception to normal acuity, variable field defects, nystagmus - ADAPTATIONS: High illumination, enlarged print, magnification, high contrast; braille and tactual materials may be needed - CONSIDERATIONS: Avoid visual clutter, images should be simple and presented in isolation. When teaching avoid standing in front of a busy background and wearing busy patterns. Modify expectations to accommodate fluctuating visual performance. Vision stimulation programming is essential for young children to help them learn how to interpret what they see.

Cortical Visual Impairment

Damage to the visual cortex or the posterior visual pathways. Pervasive neurological diorders such as cerebral palsy, epilepsy, hydrocephalus, learning disabilities, or deafness may be present. Occasionally, optic nerve atrophy, optic nerve hypoplasia, retinal abnormalities, and other ocular lesions occur. Spatial confusion is common - fluctuation in visual functioning, eye structure may be healthy and intact, sometimes absence of nystagmus, inattention to visual stimuli, preference of touch over vision as the primary exploratory sense, difficulty seeing objects or picutres which are placed close together, difficulty discriminating figure-ground, may have more peripheral than central vision or vice versa. Color perception is generally intact. Visual improvement sometimes occurs over a period of time after the initial insult to the brain. Light gazing frequently occurs. Can cause photophobia. Student may bring objects close to their eyes to block out the extraneous visual clutter in order to concentrate more easily on the object - ADAPTATIONS: High illumination, bright contrast in materials, using consistent visual cues throughout different settings such as school, home and community. A combination of reading media may be necessary - CONSIDERATIONS: Most students are also multiply impaired. It is necessary to determine which sensory system gives the most accurate info to the student and then pair visual skills with that system. Visual input must be controlled to prevent visual overloading. Visual images should be simple and presented in isolation. Repetition and routines are very helpful. Tell students what they are seeing and encourage them to feel it and explore it while learning about it. Color coding simple pictures or shapes gives an additional cue for recognition. Restrict the number of people who are directly involved in intervention. When preparing reading materials, use a contrasting paper, template or p=marker to block out some of the visual info, or space objects further apart on a page. Demonstrate how to use a finger to move from one object to the next on a page. Simplify illustrations. Fluctuations in visual performance may be reduced by eliminating tiredness, extraneous noise, and other distractors. It may be necessary to turn off a light or use diffused lighting to get students to focus on a task.

Astigmatism

Defect in the curvature of the cornea, light rays cannot focus on a single point on the retina - blurred vision, commonly occurs with albinism and keratoconus, tendency to frown to create a pinhole effect - ADAPTATIONS: corrective lenses, good contrast and lighting - CONSIDERATIONS: may tire easily and complain of headhaches when reading and doing close work

Choroideremia

Degeneration of pigment and retinal atrophy - In males, night blindness, consitricted visual field, progressive blindness. In females, nonprogressive, normal vision, often an atypical retinopathy - ADAPTATIONS: diffused lighting with no glare, absorptive lenses, infra-red viewing devices, prism glasses to increase visual field, closed circuit television for maximum contrast, reversed polarity - CONSIDERATIONS: Physical activities and mobility may be restricted by low light situations such as bad weather and nighttime. Teach organized search patterns using a grid pattern to aid the student in locating objects or visual targets. Students may need to be seated farther away to increase their visual field.

Sclerosis

Disease of the choroid leading to the slow loss of central vision in middle life - Affects central vision, photophobia, poor color vision, normal peripheral vision - ADAPTATIONS: Eccentric viewing, magnification to enlarge the image beyond the scotoma, enlargement of materials or bringing materials closer to the eye, diffused less intense light may permit the eyes to enlarge the pupil so more area can be viewed, telescopes for distance vision, tinted glasses, sunglasses and eyeshades, CCTV with reversed polarity, adjustable lighting without glare - CONSIDERATIONS: High contrast line markers or templates may be helpful for reading, finding math problems, or locating other important info.

Ptosis

Dropping of the eyelid, may be unilateral or bilateral, constant or intermittent - Reduced visual field may cause amblyopia - ADAPTATIONS: Frames can be worn that have a wirse crutch that elevates the lid - CONSIDERATIONS: Position and placement for activities may affect visual efficiency.

Optic Atrophy, Optic Nerve Atrophy

Dysfunction of the optic nerve resulting in the inability to conduct electrical impulses to the brain causing loss of vision. The optic disc becomes plae and there is a loss of pupillary reaction - Fluctuating visual performance, blurred vision, color vision and night vision may be impaired, visual perception may be impaired; may be photophobic - ADAPTATIONS: High illumination, enlarged print, magnification, high contrast; braille and tactual materials may be needed - CONSIDERATIONS: Avoid visual clutter, images should be simple and presented in isolation. When teaching avoid standing in front of a busy background and wearing busy patters. Modify expectations to accommodate fluctuating visual performance. Vision stimulation programming is essential for young children to help them learn how to interpret what they see.

Hyperopia

Farsightedness, a refractive error in which the focal point for light rays is behind the retina; shortness of the eyeball. If not corrected, close work may cause nausea, headhach, dizziness, and eye rubbing - Difficulty seeing at close distance - ADAPTATIONS: Corrective lenses, magnifiers - CONSIDERATIONS: students may tire easily when reading and doing close work. Variation in near and far tasks can precent tiring. Studnets may prefer physical education activities and activities that require distance vision.

Histoplasmosis, Presumed Ocular Histoplasmosis (POHS)

Fungus infection causing retinal damage - Macula damage or central scotomas cause patchy fields, central vision loss and deficient color vision while peripheral damage causes loss of night vision. When the retinal damage is in the central area, see the adaptations and educational considerations in macular disease. When the damage is in the periphery, see the adaptations and educational considerations in retinitis pigmentosa - ADAPTATIONS: microscopes, telescopes, good contrast and lighting - CONSIDERATIONS: High contrast line markers or templates may be helpful for reading, finding math problems, or locating other important info.

Presbyopia

Gradual hardening of the lens which increases with age - Reduced ability to accommodate - ADAPTATIONS: Good lighting and contrast

Buphthalmos

Infantile glaucoma that starts at birth or within first three years - photophobia, increased ocular pressure, tearing, damage of optic disc, increased corneal diameter, corneal opacity, increased depth of the anterior champ=ber, as well as general enlargement of the anterior chamber of the eye. Blindness occurs if left untreated. - ADAPTATIONS: good contrast and lighting may be helpful - CONSIDERATIONS: if blindness occurs, tactual and auditory modes will need to be developed

Toxoplasmosis

Inflammation of the retina and choroid which causes scarring. Congential toxoplasmosis infects the fetus in utero; acquired toxoplasmosis can develop anytime - Field loss, scotomas or vlind spots, possibly lass of central vision, and squinting. When the retinal damage is to the central area, see the adaptations and educational considerations in macular disease. When the damage is in the periphery, see the adaptations and educational considerations in retinitis pigmentosa - ADAPTATIONS: Microscopes, telescopes, eccentric viewing - CONSIDERATIONS: High contrast line markers or templates may be helpful for reading, finding math problems or locating other important info.

Uveitis

Inflammation of the uveal tract which can involve the choroid, the cillary body, and/or the iris. - If the uveitis is acute or chronic anterior (iritis) there may be pain, photophobia, and blurred vision. Other forms cause blurred vision, redness, and little or not pain - ADAPTATIONS: Good contrast and glare reduction, more time to adjust to new situations - CONSIDERATIONS: Lights with rheostats and adjustable arms are helpful for close work

Nystagmus

Involuntary eye movements which can be horizontal, vertical, circular or mixed. Can be elicited when someone watches certain kind of moving objects - Inability to maintain steady fixation, reduced visual acuity, fatigue, vertigo - ADAPTATIONS: Shifting gaze or head tilting may help to find the null point which slows the nystagmus - CONSIDERATIONS: Stress and spinning or other rhythmic movements increase nystagmus, and should be avoided when visual functioning needs to be maximized. Close work causes fatigue and visual tasks should be varied to provide rest for the eyes. Line markers, rulers, typoscopes, and other templates may be helpful to keep the place on the page. Good lighting and contrast are helpful.

Amblyopia ex anopsia

Lazy eye, reduced visual functioning in one eye - monocularity, some field loss, poor or absent depth perception - ADAPTATIONS: good contrast and glare reduction - CONSIDERATIONS: Close work may result in loss of place, eye fatigue, blurring of print, poor concentration, frequent rest periods, seating that favors good eye, familiarization with the environment so can anticipate distances and heights

Wilm's Tumor

Malignancy of the kidney, small stature, developmental delays. Often accompanies aniridia - Total or partial absence of iris, cataracts, ptosis, decreased visual acuity, photophobia, nystagmus - ADAPTATIONS: Pinhole contact lenses tinted sunglasses and eye shades, dim lighting, rheostats and lighting controls, magnification - CONSIDERATIONS: Lighting conditions will need to be controlled to ensure optimal classroom performance. Teacher should not stand in front of the window or light source when teaching or speaking to the student.

Myopia

Nearsightedness. A refractive error where the image of a distant object is formed in front of the retina and cannot be seen distinctly; elongation of the eyeball - Inability to see at distances. Near vision is rarely affected. Squinting and frowning may be indications of difficulty seeing things at a distance. Degenerative myopia can cause severe nearsightedness, is progressive and often visual acuity cannot be corrected to normal with lenses. Diagnosis is based on changes observed in the retina and the choroid. Detached retina, choroidal hemorhages, reduced central vision, opacities of the vitreous, macular swelling, and cataracts can occur - ADAPTATIONS: Corrective lenses, high illumination with minimal glare, contact lenses - CONSIDERATIONS: With degenerative myopia, students may need to move closer to see the blackboard and classroom demonstrations. Students who have progressive myopia should observe precautions for retinal detachment. Students may not be interested in activities that require distance vision, especially physical education activities.

Cataracts

Opacity or cloudiness of the lens which restricts the passage of light, usually bilateral. Immature or incipent cataracts are only slightly opaque; mature cataracts are so opaque that the fundus cannot be seen and the pupil may be white - reduced visual acuity, blurred vision, poor color vision, photophobia, sometimes nystagmus. Visual ability fluctuates according to light. Squint or strabismus may be early manifestations of congenital cataracts. Amblyopia may result if not corrected. After surgery the eyes cannot accommodate without lens prescriptions - ADAPTATIONS: Magnification, enlargement, or bringing the materials closer to the eyes. Eccentric viewing may be helpful. Lighting should come from behind the student and glare should be avoided. If cataracts are centrally located, near vision will be affected and bright light may be a major problem. Low level of illumination may be preferred. If cataracts are in the peripheral area, bright light may be needed to close the pupil and allow the iris to cover most of the cataract area. If the lens has been removed, see aphakia - CONSIDERATIONS: Teacher should not stand in front of the window or the light source when teaching or speaking to the student. Lights with rheostats and adjustable arms are helpful for close work. If contact lenses or glasses are prescribed, they should be worn. Time may be needed for adjustment to different lighting situations. Rest period may be needed when doing close work, and variation of near and distant tasks can prevent tiring.

Retinal Detachment

Parts of the retina pull away from the supporting structure of the eye and atrophy - Field loss, blurred vision, scotomas or blind spots, possible loss of central vision; myopia and stabismus often occur when there is remaining vision. When the retinal detachment is in the central area, see the adaptations and educational considerations in macular disease. When the detachment is in the periphery, see the adaptations and educational considerations in retinitis pigmentosa - ADAPTATIONS: Magnification for close work, telescopes for distance viewing, eccentric viewing, high illumination. Elliminate glare - CONSIDERATIONS: Avoid contact sports and any physical activity that may result in a sudden jar of the head to prevent further detachment.

Chorioreentinitis

Posterior uveitis or an inflammation of the choroid that spreads to the retina - can cause blurred vision, photophobia, distorted images, central scotomas - ADAPTATIONS: Eccentric viewing, magnification to enlarge the image beyond the scotoma, enlargement of materials or bringing materials closer to the eye, diffused less intense light may permit the eyes to enlarge the pupil so more area can be viewed, telescopes for distance vision, tinted glasses, sunglasses and eyeshades, closed-circuit television with reversed polarity, adjustable lighting without glare - CONSIDERATIONS: high contrast line markers or templates may be helpful for reading, finding , math problems, or locating other important info

Retinitis pigmentosa

Progressive disorder that causes degeneration primarily of the light sensitive cells in the periphery of the retina. There are numerous diseases grouped together which damage the retina in this way but manifest additional different characteristics. These include: Usher's syndrome, Leber's congenital amaurosis, Laurence-Moon-Biedi syndrome, and Bassen-Kornzweig syndrome - Loss of peripheral vision, night blindness, tunnel vision, decreased acuity and depth perception, spotty vision beacuase of retinal scarring, and photophobia. Cataracts can develop. May be accompanied by myopia, vitreous opacities, cataracts, or keratoconus. Total blindnessoccurs in some cases - ADAPTATIONS: High illuminationwith no glare, absorptive lenses, infra-red viewing devices, prism glasses to increase visual field, CCTV for maximum contrast - CONSIDERATIONS: Physical activities and mobility may be restricted by low light situations such as bad weather and night time. Teach organized search patters using a grid pattern to aid the student in locating objects or visual targets. Students may need to be seated farther away to increase their visual field. Precautions should be taken to prevent retinal detachment.

Macular Disease, Macular Degeneration (Age Related Macular Degeneration). Congenital Macular Disease

Progressive or degenerating damage to the central part of the retinal cones - Affects central vision, photophobia, poor color vision, normal peripheral vision - ADAPTATIONS: Eccentric viewing using peripheral vision, magnification to enlarge the image beyond the scotoma, enlargement of materials or bringing materials closer to the eye, diffused less intense light may permit the eyes to enlarge the pupil so more area can be viewed, telescopes for distance vision, tinted glasses, sunglasses and eyeshades, CCTV with reversed polarity, adjustable lighting without glare - CONSIDERATIONS: High contrast line markers or templates may be helpful for reading, finding math problems. or locating other important info. Teachers should not stand in front of a window or light source when teaching or speaking to the student. Lights with rheostats and adjustable arms are helpful for close work. Fatigue can become a problem. Students may need to be seated near the chalkboard.

Aniridia

Total or partial absence of iris - decreased visual acuity, photophovia, and field loss where iris is absent, cataracts and glaucoma are frequently present, vision may fluctuate depending on lighting conditions and glare - ADAPTATIONS: cosmetic contact lenses, tinted lenses, sunglasses, dim lighting, magnification - CONSIDERATIONS: lighting conditions, teacher sohould not stand in front of the window or light source when teaching or speaking to student, paper copies of overhead transparancies, be sensitive to eye fatigue

Albinism

Total or partial lack of pigment causing abnormal optic nerve development, may be sensitive to sun - decreased visual acuity, photophobia, astigmatism, mystagmus, central field loss, strabismus - ADAPTATIONS: magnification, high contrast, tinted lenses, sunglasses, enhanced print - CONSIDERATIONS: lighting conditions, high contrast line markers, teacher should not stand in front of the window or light source when teaching, paper copies of overhead transparancies, eye fatigue esp. when doing close work, difficulty with depth perception