Pediatric Annals

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Retinal Diseases in Children

Anwar Shah, MD; Eugene McCabe, MD; M Nichole Delsoin, MD

Abstract

RUBELLA

Congenital rubella affects the newborns of mothers who lacked natural or induced immunity to the rubella virus and contracted the disease during early pregnancy. The congenital disease causes spontaneous abortions or stillbirths in 10% of those cases. When the fetus survives the infection, congenital defects involving the eyes, ears and heart are found. In addition, the central nervous system, hematopoietic, respiratory and genitourinary systems can be affected. The infant may be deaf and microcephalic. Both the anterior and posterior segments of the eyes may be involved. Congenital rubella causes microphthalmia or small eye, alterations of the pigment layer of the retina (pseudo retinitis pigmentosa), cataracts, opacification of the cornea, glaucoma and or chronic inflammation of the anterior segment of the eyes (uveitis).

Pigmentary retinopathy, which occurs in 70% to 75% of cases gives to the fundus a "salt and pepper" appearance as seen in syphilitic retinopathy. It can be the only sign of the disease and visual acuity can be unaffected.

The cataracts may be unilateral but most often are bilateral. If the lens becomes completely opaque it may cause a "leukokoria" or white pupil which brings the patient to the ophthalmologist's attention. Cataract surgery can be complicated in those patients because of the continuous inflammation due to the presence of the virus in the anterior segment during the first few vears of life.

TOXOPLASMOSIS

Another congenital disease, toxoplasmosis, willalso be seen by the ophthalmologist because of a "white pupil" (or leukokoria) or because of microphthalmia. The fetus is infected by transmission through the placenta and at birth shows the usual signs of a congenital infection including low birth weight, jaundice and hepatosplenomegaly. The fetal brain and the eyes are the most susceptible to damage and the infant will present with hydrocephalus and extensive lesions of the fundus. Intracranial calcifications are found on x-rays of the skull. He may have a cataract and an organized (scarred) vitreous. However, the disease may also run a mild course in utero, and healed chorioretinal scars are found at birth, which may later in life show reactivation of the process of destruction. Those scars are large, usually located in the posterior pole near the macula. They are yellow white with an irregular border of marked pigmentation. Such scars should be regularly examined by an ophthalmologist because of the possible reactivation with involvement of the macula. Treatment with Pyrimethamine, sulfadiazine, steroids and folinic acid has had some success and laser photocoagulation can be tried. Other forms of treatment are under study.

TOXOCARA

Toxocara or visceral larva migrans also presents clinically sometimes as leukokoria and must then be distinguished from the far more serious, malignant disease, retinoblastoma, which arises in the same age group.

Toxocara is acquired by children three years of age and older who ingest dirt contaminated with dog or cat feces containing toxocara eggs. The eggs hatch in the intestines and the larvae are carried in the bloodstream to the retina and the choroid. The lesion which is granulomatous and inflammatory can be seen in the fundus either as a yellowish elevation of the retina or a totally disorganized retina and vitreous showing behind the lens and giving the white pupil appearance. The diagnosis is based on clinical findings in the eye, the eosinophilia and the biopsy of larva infested tissue. Corticosteroids may be helpful in decreasing the inflammatory reaction in the eye.

COATS' DISEASE

A patient with Coats' Disease most likely will be a male one to eight years old walking into the office with a history of sudden decrease of vision in one eye and may have a white pupil.…

RUBELLA

Congenital rubella affects the newborns of mothers who lacked natural or induced immunity to the rubella virus and contracted the disease during early pregnancy. The congenital disease causes spontaneous abortions or stillbirths in 10% of those cases. When the fetus survives the infection, congenital defects involving the eyes, ears and heart are found. In addition, the central nervous system, hematopoietic, respiratory and genitourinary systems can be affected. The infant may be deaf and microcephalic. Both the anterior and posterior segments of the eyes may be involved. Congenital rubella causes microphthalmia or small eye, alterations of the pigment layer of the retina (pseudo retinitis pigmentosa), cataracts, opacification of the cornea, glaucoma and or chronic inflammation of the anterior segment of the eyes (uveitis).

Pigmentary retinopathy, which occurs in 70% to 75% of cases gives to the fundus a "salt and pepper" appearance as seen in syphilitic retinopathy. It can be the only sign of the disease and visual acuity can be unaffected.

The cataracts may be unilateral but most often are bilateral. If the lens becomes completely opaque it may cause a "leukokoria" or white pupil which brings the patient to the ophthalmologist's attention. Cataract surgery can be complicated in those patients because of the continuous inflammation due to the presence of the virus in the anterior segment during the first few vears of life.

TOXOPLASMOSIS

Another congenital disease, toxoplasmosis, willalso be seen by the ophthalmologist because of a "white pupil" (or leukokoria) or because of microphthalmia. The fetus is infected by transmission through the placenta and at birth shows the usual signs of a congenital infection including low birth weight, jaundice and hepatosplenomegaly. The fetal brain and the eyes are the most susceptible to damage and the infant will present with hydrocephalus and extensive lesions of the fundus. Intracranial calcifications are found on x-rays of the skull. He may have a cataract and an organized (scarred) vitreous. However, the disease may also run a mild course in utero, and healed chorioretinal scars are found at birth, which may later in life show reactivation of the process of destruction. Those scars are large, usually located in the posterior pole near the macula. They are yellow white with an irregular border of marked pigmentation. Such scars should be regularly examined by an ophthalmologist because of the possible reactivation with involvement of the macula. Treatment with Pyrimethamine, sulfadiazine, steroids and folinic acid has had some success and laser photocoagulation can be tried. Other forms of treatment are under study.

TOXOCARA

Toxocara or visceral larva migrans also presents clinically sometimes as leukokoria and must then be distinguished from the far more serious, malignant disease, retinoblastoma, which arises in the same age group.

Toxocara is acquired by children three years of age and older who ingest dirt contaminated with dog or cat feces containing toxocara eggs. The eggs hatch in the intestines and the larvae are carried in the bloodstream to the retina and the choroid. The lesion which is granulomatous and inflammatory can be seen in the fundus either as a yellowish elevation of the retina or a totally disorganized retina and vitreous showing behind the lens and giving the white pupil appearance. The diagnosis is based on clinical findings in the eye, the eosinophilia and the biopsy of larva infested tissue. Corticosteroids may be helpful in decreasing the inflammatory reaction in the eye.

COATS' DISEASE

A patient with Coats' Disease most likely will be a male one to eight years old walking into the office with a history of sudden decrease of vision in one eye and may have a white pupil. On examination the fundus shows dilated, telangiectatic blood vessels leaking fluid and blood under the retina, causing a retinal detachment that may be total. Vision drops when the macula is affected by the leakage. Laser photocoagulation can be helpful in certain cases but the macular scar is permanent.

HEREDITARY PIGMENTARY DEGENERATIONS

Retinitis Pigmentosa

Patients affected by this disorder usually complain of night blindness. At the onset, retinal examination is sometimes negative but visual fields testing and ERG (electroretinography) can detect the abnormality. The visual fields are constricted and the ERG decreased or extinguished.

Later the fundus exam shows black "bony spicules" of pigment scattered throughout the mid-periphery of the retina, bordering the blood vessels and progressing toward the posterior pole and the periphery. Those changes are accompanied by disc atrophy and attenuation of the retinal arterioles. Finally, the visual field constricts totally and vision is lost. There is also a remarkable association with cataract, macular degeneration and glaucoma in these patients.

The disease is inherited as X-linked recessive (the most severe), autosomal dominant (the mildest form) or autosomal recessive (intermediate). At the present time, only counseling is available for those youngsters.

Retinitis Pigmentosa Sine Pigmento

This disease is the same as retinitis pigmentosa but no bony spicules are seen in the retina.

Retinitis Punctata Albescens

Retinitis punctata albescens closely resembles retinitis pigmentosa, but the fundus harbors instead little white dots scattered throughout. The symptoms and clinical course are the same as in retinitis pigmentosa and it is autosomal recessive.

Fundus Albipunctatus

A less severe form of retinitis pigmentosa albescens is fundus albipunctatus since vision remains good and the psychophysiologic tests (ERG) remain normal. The fundus also shows the white dots. It is autosomal recessive.

Fundus Flavimaculatus

Fundus flavimaculatus is also characterized by tiny yellow white dots deep in the retina seen along the choroidal vessels. This is an autosomal recessive disease. Sometimes it is associated with macular degeneration and decreased visual acuity. The ERG is usually normal.

Macular Degenerations

Macular degenerations occur in children either as a primary disease or in association with systemic diseases.

The Vitelliform Degeneration of Best (Best's disease)

This is an autosomal dominant disease with congenital or late onset. The fundus exam shows an egg yolk-like "sunny-side-up" appearance of the macula. Vision starts to drop when the "egg scrambles" and a pigmentary scar takes its place, destroying the macula. There is no known treatment.

Juvenile Macular Dystrophy of Stargardt

An autosomal recessive disorder, this is seen in children between the ages of six and 14 as well as in young adults. The disease manifests itself by a rapid decrease of vision before any changes can be seen in the retina. The characteristic retinal lesion appearing later is a "peau d'orange" or beaten bronze look with a center of clumped pigment in the macula. At times a retinitis pigmentosa picture can be seen.

Macular degenerations can be seen in association with: Von Gierke's disease, Gaucher's disease, Fabry's disease, gangliosidoses, Niemann-Pick infantile disease, lactosyl ceramidosis, Farber's disease, and leukodystrophies.

PHAKOMATOSES

The term "phakomatosis" is derived from the Greek work "phakos" which means mother spot. This word is used to encompass primarily four different disease entities which have in common ocular, skin, and intracranial manifestations. These four diseases are neurofibromatosis, tuberous sclerosis, angiomatosis retinae, and encephalotrigeminal angiomatosis.

Neurofibromatosis, also known as von Recklinghausen's disease, is a congenital disorder inherited through a dominant gene. The disease generally appears at puberty, although it is congenital and can occur at birth or even in utero. The skin lesions include the flat coffee-colored cafe au lait spots which are quite common on the trunk. The plexiform neurofibroma is another common skin lesion which can be so diffuse so as to hang in folds forming the characteristic elephantiasis neuromatosis. The third variety of skin lesion is the fibroma molluscum which can appear as small pedunculated lesions.

The systemic and intracranial manifestations include mental retardation, epilepsy, behavior problems and pheochromocytoma. The intracranial signs and symptoms of the disorder include those associated with increased intracranial pressure such as papilledema, sixth nerve palsy, nausea and vomiting, and headache. These symptoms are associated with central nervous system mass lesions such as acoustic neurofibromas, gliomas and meningiomas.

The ocular lesions include plexiform neuromas of the eyelids which may form an S configuration of the lid margin. These lesions of the eyelids can be quite extensive and are able to produce ptosis of the eyelid. Neurofibromas can also occur on the iris and usually take the form of multiple small tan nodules. Neurofibromas have also been noted on the conjunctiva, cornea, and in the choroid and retina. Those in the retina appear as small, single or multiple, flat to moderately elevated, whitish lesions. Congenital glaucoma is also associated with this disorder. It is particularly severe and generally has a higher incidence when the upper lid is involved. The glaucoma is usually unilateral and of an open angle type. The glaucoma may occur at birth or at any time thereafter.

The orbital lesions associated with neurofibromatosis are often quite characteristic. An x-ray of the skull and orbit may reveal a generalized enlargement of the orbit, enlargement of the optic canal due to the presence of an optic nerve glioma, enlargement of the pituitary or middle cranial fossa, and abnormalities of the sphenoid bone. Defects of the greater wing of the sphenoid are sometimes associated with a pulsating exophthalmos due to transmission of the cranial pulsation through the bony defect.

In general, the treatment for this disorder is palliative. The major concern of the ophthalmologist is the severe congenital glaucoma that occasionally occurs. Since early treatment of the glaucoma is essential to preserve as much vision as possible in these children, a child with suspected neurofibromatosis warrants a complete ophthalmological examination.

Another of the phakomatoses is tuberous sclerosis, also known as Bourneville^ disease. This disorder is inherited as an irregular dominant trait and is characterized by the triad of adenoma sebaceum, mental retardation, and epilepsy. The cutaneous manifestations usually develop between two and five years of age and consist of the "adenoma sebaceum," which is actually an angiofibroma. These lesions generally start as pink« mildly elevated nodules, commonly found in a butterfly pattern about the face. Another skin abnormality which is quite characteristic of this disease that may be present at birth consists of ash-leaf spots. These lesions are most commonly located on the trunk of the patient and are said by some to be pathognomonic of this disease.

The systemic manifestations include marked mental retardation, and seizures of the grand mal, petit mal, or jacksonian type. These CNS manifestations a re secondary to glial proliferation in the brain forming the cortical tubers which are sometimes seen on standard skull x-rays as areas of calcification. These lesions may lead to increased intracranial pressure and resultant papilledema and optic atrophy.

The major ocular lesions of this disorder consist of retinal hamartomas. They most frequently arise from the disc or in the peripapillary retina, although they do occur in the retinal periphery. They usually appear as oval, yellow to gray-white, nodular discrete masses, generally with no accompanying inflammation. Their size is quite variable, from one-quarter to three or more disc diameters. They may be single or multiple, and may or may not be associated with calcification. These lesions are sometimes referred toas mulberry lesions because of their similar appearance. Secondary complications from these lesions include intraocular inflammation, hemorrhage and secondary glaucoma. Giant drusen of the optic nerve are also seen with increased frequency in this disease.

The prognosis for these patients is extremely poor. Most of these children require early institutional care and many the in childhood and early adolescence. As far as the vision of these children is concerned, it is quite variable. Most of the vision loss is attributable to the intracranial lesions and the resultant papilledema and optic atrophy. Treatment of the eye lesions of this disorder is confined mainly to dealing with the secondary complications mentioned above. The ocular lesions themselves require no specific treatment. The role of an ophthalmologist, therefore, consists chiefly of assisting to make the diagnosis, and treating these secondary eye complications.

Another of the diseases termed phakomatosis is angiomatosis retinae, also known as von Hippel-Lindau's disease. This disease is inherited as an irregular dominant. The systemic manifestations of this disease include the cerebellar hemangiomas which were first described by Lindau. Lesions in this area may give rise to the signs and symptoms associated with a posterior fossa mass. Involvement of the cerebellum may also give rise to various seizure disorders. Other systemic findings include renal cysts and tumors, pancreatic cysts, and pheochromocytomas.

The ocular manifestations consist of retinal hemangiomas. This lesion generally consists of an oval globular reddish mass in the retinal periphery with a markedly dilated and tortuous retinal artery and vein leading to and from the lesion. These retinal lesions are bilateral in approximately 50% of the patients. They can lead to retinal hemorrhages, retinal transudation and exudation, retinal detachments, vitreous hemorrhage, and ultimately secondary glaucoma.

The prognosis for this disorder is fairly good if treatment is initiated before major eye complications occur. The treatment generally consists of retinal photocoagulation for lesions that are undergoing hemorrhage or significant exudation. These lesions are treatable at an early stage, and since useful vision can often be preserved, any patient diagnosed with von HippelLindau's disease warrants a complete ophthalmological examination.

The last of the phakomatoses to be discussed is encephalotrigeminal angiomatosis, also knownasSturgeWeber syndrome. The cutaneous manifestations of the disease consist of the nevus flammeus, better known as the port-wine stain. This generally involves the face in the area of the first or second division of the fifth cranial nerve, and therefore frequently involves the eyelid skin. An intracranial lesion on the same side as the cutaneous involvement is also frequently present.

The systemic manifestations include intracranial hemangiomas which generally involve the meninges on one side of the brain, leading to contralateral jacksonian seizures, hemiparesis, hemianopia, and, at times, mental retardation. These intracranial lesions may appear on skull x-rays as fine parallel lines which have been called "tram tracks."

The ocular manifestations include angiomas of the lid, conjunctival vessel dilatation and tortuosity, and heterochromia iridis. Choroidal involvement often gives a tomato catsup appearance due to the diffuse hemangioma present in this area. This is the most outstanding fundus change. The most serious of the ocular lesions is the occurrence of congenital glaucoma which is usually homolateral to the facial involvement. This form of glaucoma is a treatable entity and is dealt with in the same manner as other forms of congenital glaucoma, namely, surgical intervention.

Generally, the prognosis for these patients is good. Since the most serious of the ocular findings is glaucoma, and since early treatment is essential to preserve useful vision, a patient diagnosed with this entity warrants a thorough eye examination.

RETINAL DETACHMENTS

Idiopathic retinal detachments or retinal detachments due to retinal breaks or retinal holes are very rare in children. The most common causes of rhegmatogenous retinal detachment in children are trauma and retrolental fibroplasia. Less common causes are congenital inferior temporal dialysis, myopia, lattice degeneration, aphakia and uveitis.

Traumatic Retinal Detachment

The trauma is usually direct to the eyeball and could be a blunt injury or a penetrating injury. In a blunt injury, the most common site of the retinal tear causing the detachment is the posterior vitreous base at the inferotemporal quadrant, the second most common site is the posterior vitreous base in the upper nasal quadrant, less commonly other areas in the peripheral retina may be involved. The posterior vitreous base is located in the peripheral retina posterior to the ora serrata (anterior edge of the retina). Because of the common location of the retinal tear and the retinal detachment in the inferotemporal quadrant, symptoms of decreased visual acuity or field defect may not be present until the central retina is involved and thus a diagnosis may not be made for many months or even years after the injury. With modern surgical methods, consisting of scleral buckling diathermy and/or cryopexy the prognosis in traumatic retinal detachments with dialysis is excellent. A child's eye with a history of blunt trauma should be checked by an ophthalmologist at periodic intervals to detect dialysis or breaks in the retinal periphery which can occur many months after the injury.

Retrolental Fibroplasia

The majority of patients have a birth weight of between 3 lbs. and 4 lbs. and the age at which a retinal detachment occurs in this group ranges from ten to 19 years with an average of three to five years. The etiology is retinal holes in the retinal periphery caused by vitreous adhesions and vitreous traction from the progressive cicatrical retrolental fibroplasia. The treatment again is surgical consisting of a scleral buckling operation.

Congenital Inferotemporal Dialysis

This is usually bilateral and located inferotemporally. The prognosis with surgery is excellent.

Retinal detachments due to myopia, aphakia and lattice degeneration have a favorable surgical prognosis. Surgery is not indicated for retinal detachment secondary to uveitis, these are treated medically.

RETINOBLASTOMA

This is the most common intraocular tumor of childhood, it rarely occurs in adults. All bilateral cases are assumed to be hereditary and 5% to 10% of unilateral cases may be hereditary. The tumor arises from the nuclear layers of the retina. It occurs in about one out of every 14,000 to 23,000 births and has no predilection for race or sex. Involvement is bilateral in about 25% to 35% of cases. The average age at the time of diagnosis is 13 months, in 72% of cases the diagnosis is made before the age of three, and in 90% by the age of four years. Normal parents having one child affected with non-hereditary retinoblastoma have a less than one in 20,000 chance of producing another affected child. Phenotypically normal parents with two affected children run a 50% risk foreach additional child being at least a carrier and 40% chance that each child will exhibit the tumor, based upon a gene penetrance of 80%. An affected individual who has survived a proven hereditary retinoblastoma will have a 40% risk that each offspring will be affected. An individual surviving the sporadic variety of tumor will have at least a 5%, chance of producing affected offspring. Healthy children of an individual surviving the inherited variety of tumor will have about a 7% chance of producing affected offspring.

The clinical characteristics of the tumor depend upon the stage when it is first discovered. In the early stages the presenting complaint may be decreased vision or strabismus. As the tumor progresses it may grow from the retina into the vitreous or into the choroid. In either case a white pupillary reflex results. The tumor is a pale pink or white mass with newly formed blood vessels on its surface. There may be many independent tumors or implantation growths on the surface of the iris, cornea or vitreous. The vitreous may contain many globules of dull white tumor seeds. Calcium may occur within the tumor. In advanced stages the tumor may necrose and may present as a severe uveitis or endophthalmitis. Hypopyon or hyphema may be present. Rarely children may be seen with a proptosis or metastasis.

The diagnosis is made by radiological studies, computed tomography, ultrasound, the presence of calcium in the tumor in orbital x-rays and histological examination of the enucleated eye with the advanced tumor. The fellow eye should be carefully examined with scleral depression and indirect ophthalmoscopy with the child anesthetized and the pupil well dilated. All parts of the retina should be examined and careful attention should be directed to the periphery.

Treatment of retinoblastoma is highly individualized and depends upon the size, number and location of tumors present. Often one eye is in an advanced stage and may need enucleation. Tumors in the fellow eye depending upon the size, location and numbers of the tumor may be treated with external beam radiation combined with cryopexy, photocoagulation, radioactive cobalt, Cytoxan and vincristine. The fellow eye should be examined under general anesthesia every three or four months following surgery and at less frequent intervals thereafter throughout childhood.

The prognosis for retinoblastoma depends upon whether the tumor is unilateral or bilateral and the stage when it is first diagnosed. If the lesion is unilateral, diagnosed early and treated promptly by adequate enucleation, there is a 90% chance for survival.

The prognosis is unfavorable if the disease is bilateral, if there is extension to the vortex veins or to the optic nerve or if there is metastasis or extension to the cranium.

RETROLENTAL FIBROPLASIA

This disease is also referred to as retinopathy of prematurity. It occurs almost exclusively in premature infants who have a birth weight of less than 1500 g and who have been given a high concentration of oxygen during the first ten days of life. The incidence of retrolental fibroplasia increases with the concentration of oxygen and the duration of continuous oxygen treatment. The smaller the premature infant the greater the incidence of retrolental fibroplasia.

Retrolental fibroplasia is a bilateral abnormality of retinal neovascularization. In the premature infant, the blood vessels in the retina are immature and they respond to excessive oxygen by vasoconstriction and obliteration. Later, the vessels dilate and become tortuous. The remaining capillaries proliferate and new blood vessels grow into the vitreous cavity, this gives rise to formation of scar tissue and detachment of sensory retina with retinal and vitreous hemorrhages and formation of total fibrous tissue behind the lens. Retrolental fibroplasia is easily differentiated from other causes of leukokoria (white pupil). The eye is of normal size initially. The white pupil does not occur until some months after birth and is usually bilateral. The infant is premature usually under 1500 g and oxygen therapy was administered soon after birth. It occurs in almost 50% of babies weighing less than 1500 g. The retina of the premature infant should be evaluated at the cessation of oxygen treatment by an ophthalmologist with the indirect ophthalmoscope, since the initial findings of vasodilation, tortuosity and neovascularization are peripheral to the equator. Thereafter the child should be examined every three months from the first two years, every four months for the next two years, every six months for the next three years and then annually. This is because incomplete retrolental fibroplasia may result in myopia, macular pigmentation, strabismus or retinal breaks and detachment which may require surgical correction. In severe cases secondary glaucoma, corneal opacification, cataracts and enophthalmos may result.

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10.3928/0090-4481-19830701-04

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