RETINA QUIZ

Abnormal Vessels Key Diagnosis

by Mark T. Dunbar, O.D

A 46-year-old Haitian female was referred by her primary-care physician to rule out any problems associated with her hypertension and diabetes. She was also HIV-positive, and her doctors wanted to ensure there were no associated ocular complications. She complained of decreased vision in both eyes. This was not a new complaint, as she admitted not being able to see well in either eye since about the age of 17. Her CD4 count was 684 (normal count is 100) when last checked two months ago, and she did not know her viral load. She works as a seamstress and so, needs crisp vision.


Note the dense plaques of retinal pigment hyperplasia appearing in an irregular
stellate configuration in each macula.

Best-corrected visual acuities were 20/60 O.D. and 20/50 O.S. Confrontation fields were full to careful finger counting, motilities normal, and there was no afferent pupillary defect. Anterior segment showed only small, nonvisually significant pterygiums in each eye. Dilated fundus exam showed healthy optic nerves with good rim coloration and perfusion O.U. Present in the maculas of each eye were dense plaques of retinal pigment hyperplasia appearing in an irregular stellate configuration. There were no hemorrhages or subretinal fluid discharges in either macula. The accompanying fundus photographs show the other significant findings. 
 

    Quiz
    1. What is the underlying etiology for this condition?
    a. Infectious/inflammatory.
    b. Dominantly inherited dystrophy.
    c. Dilated capillaries associated with retinal telangiectasia.
    d. Opportunistic infection.

    2. What is the correct diagnosis for this patient?
    a. Pattern dystrophy of the RPE.
    b. Bilateral toxoplasmosis scars.
    c. Inactive CMV retinitis.
    d. Bilateral idiopathic juxtafoveal retinal telangiectasis.

    3.A few tiny white spots appear in each macula. What do these mostly likely represent?
    a. Drusen.
    b. Intraretinal crystals.
    c. Exudate.
    d. Small Hollenhorst plaques.

    4. Besides the appropriate optical correction, what is the best management for this patient?
    a. Laser photocoagulation.
    b. ERG.
    c. Initiation of antiviral therapy.
    d. Observation.

Discussion
This patient has bilateral idiopathic juxtafoveal retinal telangiectasis (JRT), a condition of unknown etiology characterized by abnormal retinal vessels generally located temporal to the fovea. The abnormal retinal vessels result in dilation of the retinal capillaries and telangiectasia of the fine retinal vessels with minimal exudation. Patients can also develop retinal crystals, right angle venules and retinal pigment hyperplasia. In this patient fine retinal crystals are clearly visible as small refractile deposits present within the retina. However, the overwhelming feature is the exaggerated response from the RPE resulting in densely pigmented plaques present in each macula. This patient even has the right angle venules characteristic of this condition, but are subtler because of the RPE hyperplasia. This can be seen as a blunting of the vein near the macula as the vein makes a right angle turn and dives into the retina. Often, the plaque of pigment will obscure or envelop the vein, making it difficult to see.

This condition was best characterized in 19821 and later updated in 1992.2 This disease is classified into three groups:

 • Group 1 . Typically unilateral, this group affects males more than females, with the age of onset around 35. These patients probably suffer from a mild form of Coats' syndrome. The disease is localized to an area involving 1-2 disc diameters temporal to the fovea with clearly visible retinal telangiectasis and exudation.

 • Group 2 . This is the most common form of the disease, and the form that the patient has in this case. It is bilateral, affects males and females equally and involves approximately 1 disc diameter or less of the temporal foveolar area. In some patients, the telangiectasis can involve the entire parafoveolar area. This form of telangiectasis is associated with minimal to no lipid exudation.

Superficial retinal crystals occur in about half of patients, and pigment migration is common, often obscuring the blunted venules. Plaque formation is characteristic and should suggest this diagnosis even when telangiectasis is not apparent clinically. Fluorescein angiography is diagnostic and will clearly show the area of retinal telangiectasis, even when it's not observable clinically. Visual acuity ranges from 20/15 to hand motions; the average is 20/40.

No treatment, including laser photocoagulation, has been shown to be effective in Group 2 patients. The average age of presentation is 55, which is older than when our patient presented, and even much older than when our patient admits to having developed reduced acuity.

 • Group 3 . This least common form of retinal telangiectasis typically occurs in females in their mid-50s who develop capillary occlusions and often have associated systemic disease, such as diabetes or hypertension. This is usually related to their eye condition though that was not the case here. This progressively worsens leading to capillary dropout.

Our patient had no retinal problems associated with her hypertension or diabetes. Her CD4 count was high enough that she was at a low risk to have complications associated with her HIV. Based upon the clinical findings and having an index of suspicion, we made a diagnosis of JRT. Most patients will present with much subtler forms of this disease. The slightly temporal location seen in both eyes, along with the other clinical signs, should make you suspicious for this diagnosis. Once this is accomplished the diagnosis can be easily arrived at, even without the benefit of a fluorescein angiogram.

1. Gass JDM, Oyakawa RT. Idiopathic juxtafoveolar retinal telangiectasis. Arch Ophthal 1982;100:769-80.
2. Gass JDM, Blodi BA. Idiopathic juxtafoveolar retinal telangiectasis: update classification and follow up study. Ophthalmol 1993; 100:1536-45.

Answers: 1.d; 2.b; 3.b; 4.d.
 

 

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