Fluorescein angiographic features, natural course and treatment of radiation retinopathy

Abstract

SummaryFifteen patients who developed retinopathy following radiotherapy for cephalic tumours were studied by fluorescein angiography. Nine patients with unilateral or bilateral retinopathy had serial angiograms at six monthly or yearly intervals.Angiography revealed a wide range of retin;tl microvascular changes which were graded 1-4 according to the extent and degree of capillary malformation, incom petence and closure. All patients showed slow progression of retinopathy with remo delling of the affected microvasculature and increased capillary fallout and leakage to dye.The earliest retinopathic changes were capillary dilatation and closure and micro aneurysm formation. Telangiectatic-like vessels were a feature of the established ret inopathy and probably represented collateral channels which bordered sites of capillary occlusion.Two patients with progressive macular oedema and declining vision responded favourably to focal laser photocoagulation which returned a measure of competence to some residual dilated capillaries.The first fluorescein angiographic features of radiation retinopathy were described by Chee' and Gass2 who reported a microvas culopathy characterised by capillary incom petence and closure. In 1970, Hayreh3 studied three patients with choroidal melanoma treated by Cobalt 60 applicators and docu mented a wide range of angiographic changes in the retinal vasculature and outer retina. Bagan and Hollenhorst4 reported six cases of radiation retinopathy but angiographic changes were only described in one patient. Brown et al.5 reviewed the angiographic changes in the retinae of patients receiving external beam or plaque therapy for intra ocular tumours and identified vascular occlu sion as the key pathophysiological event leading to the development of radiation retinopathy.Thompson et al.6 studied seven patients with radiation retinopathy and highlighted the value of fluorescein angiography in accu rately identifying the microvascular alter ations. Ehlers and Kaae7 also used fluorescein angiography to determine the extent of retinal and choroidal vaso-occlusive changes in infants receiving radiotherapy for retinoblas toma. Lommatzsch et al. 8,9 and Tarkkanen and LaatikainenlO documented the regression of choroidal melanomas treated with Ru 106/ Rh 106 plaques using angiographic tech niques. They reported the disappearance of most choroidal and retinal vessels within the irradiated area and noted that chorioretinal

Side effects after radiotherapy of age-related macular degeneration with the Nijmegen technique

“…At 60 Gy, 50% of patients displayed some changes, and at 80 Gy, 85-90% did so [10]. Severe retinopathy is not observed below a total dose of 50 Gy with recommended daily fractions not exceeding 2 Gy in patients without vascular disease [1,2,5].…”

“…The fluorescein angiographic hallmark of radiationinduced retinopathy is retinal capillary nonperfusion [7]. Radiation retinopathy is characterized by the presence of retinal microaneurysms, cotton-wool spots, intraretinal hemorrhages, and leakage of retinal vessels with exudates [1,2,5]. Recently investigators reported on radiation-associated choroidal neovasculopathy (RACN) [15].…”

Ocular presentations of breast cancer

“…The severity of retinopathy does not correlate with the radiation dose (Amoaku & Archer 1990a;Rudoler et al 1997) and has been known to occur with exposures as low as 50 cGy (Quinn & Clemett 1993). Clinical features resemble those of diabetic retinopathy, with microaneurysms, haemorrhages, telangiectasia and exudation.…”

Ocular complications following I-125 brachytherapy for choroidal melanoma

“…On fluorescein angiography, the earliest changes that appear are focal capillary closure with neighbouring areas of irregular capillary dilation and microaneurysms (Figure 3b). 31,33 Development of radiation-induced retinopathy and maculopathy…”