Ocular toxocariasis: a rare presentation of a posterior pole granuloma with an associated choroidal neovascular membrane.

BACKGROUND: Ocular toxocariasis is a rare infection caused by the nematode larvae of toxocara canis, which is commonly found in dogs. Human transmission is usually via geophagia, the ingestion of food contaminated with the toxocara eggs, or contact with infected puppies, often resulting in devastating ocular and/or systemic effects. Distribution is worldwide; however, a higher incidence is demonstrated in the United States. METHODS: A 17-year-old black woman sought treatment at a neighborhood health center with a report of gradual decrease in vision from her left eye over a 3-month period. Her ocular and systemic histories were unremarkable. Anterior segment evaluation revealed no signs of anterior uveitis. The posterior pole showed a 1.5 DD, round, raised, white, subretinal lesion adjacent to the fovea with an overlying serous retinal detachment and retinal hemorrhage. RESULTS: She was referred to a retinologist who performed both fluorescein and indocyanine green (ICG) angiographies. A serum toxocara ELISA test was also ordered. Fluorescein angiography revealed hyperfluorescence consistent with the granuloma. The ICG demonstrated an occult choroidal neovascular membrane (CNV) underlying the area of hemorrhage inferotemporal to the granuloma. CONCLUSION: This paper illustrates the case presentation and includes an extensive review of the ocular and systemic manifestations of toxocariases. A description of ICG videoangiography, therapeutic approaches, and management will also be discussed.

Role of indocyanine green fluorescence videoangiography in evaluation of subretinal disease.

BACKGROUND: Indocyanine green (ICG) is a sterile, water-soluble, tricarbocyanine dye that can be used in fundus angiography as an adjunct to sodium fluorescein. It has a peak spectral absorption of 805 nm in blood plasma or blood, as compared with fluorescein, which has a peak spectral absorption of 465 nm. Because the absorption and emission of ICG lies around 835 nm, transmission of energy by the retinal pigment epithelium (RPE) and serosanguinated material is more efficient in this region than in the region of visible light energy. ICG has the property of being approximately 98% bound to blood protein, disallowing extravasation of excessive dye in the highly fenestrated choroidal vasculature. METHODS: The characteristics of ICG are discussed, including administration and dosage, adverse reactions and use of infrared filters for fundus photography. In addition, two cases are presented to illustrate the clinical application of ICG for diagnosis and treatment of choroidal neovascular membranes. RESULTS: ICG videoangiography can be used to reveal subfoveal choroidal neovascular membranes not previously identified with fluorescein; angiograms can also be used to dramatically highlight retinal and choroidal changes. CONCLUSIONS: The use of ICG for fundus videoangiography provides a more accurate and complete evaluation in certain cases of subretinal and choroidal disease.

Infectious and inflammatory diseases.

The systemic conditions described in this paper are (1) sarcoidosis, (2) tuberculosis, (3) toxoplasmosis, and (4) histoplasmosis. The lung is the primary target organ of granulomatous involvement for each of these disorders. This and other similarities may confuse the diagnostic picture; however, appropriate understanding of clinical, epidemiologic, pathophysiologic, immunologic, radiologic, and serologic features assists in clearly establishing a diagnosis. The goals of this paper are to help the clinician develop a working knowledge of these four conditions, as well as an understanding of which tests are appropriate to order, how to interpret their results, and which treatment and management strategies to consider.

Progressive retinal changes observed in juvenile X-linked retinoschisis.

Juvenile X-linked retinoschisis (JXR) is a vitreoretinal dystrophy affecting males only. The macular and peripheral retinal alterations associated with this disorder are very specific. Initially, a stellate-shaped foveal schisis forms; as the patient becomes older, chronic retinal pigment epithelial disturbance leads to macular degeneration. Peripheral retinoschisis may also occur, but is only identified in about half of all patients with JXR. These changes, which represent degenerating vitreous, may be complicated by retinal breaks due to the thin layer of the schisis. This paper presents five cases of JXR in patients ranging from ages 4-70 years and discusses and photodocuments the progression of related retinal changes. A table of differential diagnoses is also included.

Macular coloboma.

Macular coloboma is a congenital retinochoroidal defect of the macular region. It is a bilateral, nonprogressive condition that is associated with decreased visual acuity and nystagmus. A case of a 14-year-old boy with an unusual presentation of extensive macular colobomata is described. Location of the lesions differentiated this case from true or typical retinochoroidal colobomata. Differential diagnosis also includes postinflammatory scarring.

Duane's retraction syndrome.

Duane's retraction syndrome (DRS) is a congenital abnormality of ocular motility that occurs in about 1% of strabismic patients. Three types have been described and the clinical features include incomitant horizontal strabismus, restricted motility and globe retraction. Head turn, upshoot or downshoot of the adducted eye, and bilaterality may occasionally be present. Since strabismus is invariably present in DRS, careful assessment of extraocular motility should be performed on all children with a suspected or confirmed eye turn. Early diagnosis may save practitioners and parents hours of time and financial investment with orthoptic and surgical management attempts. A case of DRS is presented.

Alcohol amblyopia.

Alcohol amblyopia is a disorder that affects a small percentage of alcoholic patients, most of whom are nutritionally deficient. A battery of tests is required to make the diagnosis including color vision and field testing. Once the diagnosis is made, physical, emotional, and visual rehabilitation should be undertaken. A case of alcohol amblyopia is presented along with optometric management techniques.