Retinal venous beading associated with recurrent branch vein occlusion

Roberto A. Fonseca,* MD; Marcos A. Dantas, t MD

I nherited retinal venous beading is a rare retinal vas­cular disorder. In addition to the beading, it may

present with retinal arteriolar tortuosity and episodes of apparent acute vascular decompensation character­ized by microaneurysm formation, altered vascular permeability with lipid exudation, focal edema, areas of retinal infarction, surface retinal neovascularization and vitreous hemorrhages. 1-4 The inheritance pattern of this condition is consistent with autosomal domi­nant transmission. 1•2 We describe a patient with idio­pathic retinal venous beading associated with recur­rent branch vein occlusion in one eye during 8 years of follow-up.

CASE REPORT

A 25-year-old white woman was examined because of a 10-day history of blurred vision and metamor­phopsia in her right eye. She had no previous signifi­cant ocular history, and there was no history of sys­temic diseases, ocular injury or Valsalva' s manoeuvre. The patient was not taking any birth control pills or hormonal supplements, and stated that she did not smoke. Her family history and ocular examination of relatives (her parents and two sisters underwent a complete eye examination, including indirect ophthal­moscopy) were unremarkable.

From *the Department of Ophthalmology, Sao Paulo University, Sao Paulo, Brazil, and Bahiana Medical and Public Health School, Salvador, Brazil, and tthe Department of Ophthalmology, Sao Paulo University, Ribeirao Preto, Brazil

Originally received June 29, 2000 Accepted for publication Mar. 8, 2002

Reprint requests to: Dr. Roberto A. Fonseca, R. Pedro Lessa, 118, Canela, Salvador - BA, Brazil 40110-050; fax (55-71) 336-8211; ra_carvalho@hotmail.com

This article has been peer-reviewed.

Can j Ophthalmol 2002;37: 182-3

182 Retinal venous beading-Fonseca et al

On examination the patient's best corrected visual acuity was 20/25 in the right eye and 20/20 in the left eye. The pupillary reactions, extraocular motility and external biomicroscopic examination were normal bilaterally. Fluorescein angiography of the right eye showed beading in the infratemporal venous arcade as well as branch vein occlusion (Fig. 1, top). There was diffuse leakage in the inferior macular region associat-

Fig. !-Fluorescein angiograms. Top: Beading in infratemporal venous arcade associated with vena-occlusive event. Bottom: Mid-phase fluorescein angiogram shows diffuse leakage in in­ferior macular region associated with scattered hemorrhages.

ed with blocked hypofluorescence (Fig. 1, bottom). Funduscopic examination of the left eye was normal.

Extensive investigation (antithrombin III activity, levels and activity of plasma proteins C and S antigens, titre of anticardiolipin and lupus anticoagulant antibod­ies, activated partial thromboplastin time and prothrom­bin time) failed to show any blood-clotting abnor­malities. The complete blood count, platelet count, hematocrit, erythrocyte sedimentation rate and serum levels of angiotensin I converting enzyme and C­reactive protein were within normal limits. Imaging studies (chest radiography and abdominal computed tomography and ultrasonography) revealed no changes.

The right eye continued to have venous beading and showed satisfactory resolution of the vena-occlusive event. The visual acuity improved to 20/20.

Eight years after the initial event the patient pre­sented with a new complaint of decreased vision in her right eye. She stated that there had been no changes in her health or medications during the intervening peri­od. Her visual acuity had decreased to 20/25. Fundus examination and fluorescein angiography showed a new branch retinal vein occlusion in the infratemporal venous arcade surrounding the beading veins. Exten­sive investigation (same tests and examinations as pre­viously) showed no abnormalities.

CoMMENTS

Although most reported cases of retinal venous beading have an autosomal dominant transmission, idiopathic cases have been described.4 Most typical types of vena-occlusive events occur at arteriolo-

Retinal venous beading-Fonseca et al

venous crossing points. The finding of a vena-occlu­sive event in the mid-segment of the vein usually implicates some sort of clotting abnormality or an inflammatory event, which were not found in our patient.

A more likely cause for our patient's occlusive events probably lies in the alterations in the calibre and increased tortuosity of her retinal veins. It is possible that turbulence and stasis induced by the venous struc­tural abnormality may damage the vascular endotheli­um, putting her at higher risk for thrombosis. This may explain why retinal vein occlusion developed at such an early age without any other coexistent systemic prob­lems.

Our case demonstrates a complication of a venous malformation and suggests that the existence of retinal venous beading may predispose affected patients to recurrent venous occlusions. Thus, such patients should be closely monitored and should avoid risk fac­tors for thrombosis.

REFERENCES

1. Meredith T A. Inherited retinal venous beading. Arch Ophthalmol1987;105:949-53.

2. Stewart MW, Gitter KA. Inherited retinal venous beading. Am J Ophthalmol1988;106:675-8l.

3. Piguet B, Gross-Jendroska M, Holz FG, Bird AC. Inherited venous beading. Eye 1994;8(pt 1):84-8.

4. Keyser BJ, Ferguson JB. Retinal venous beading with recur­rent preretinal hemorrhage. Am J Ophthalmol 1997;123: 696-8.

Key words: branch vein occlusion, retinal venous beading, venous abnormality

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