Case A 40-year-old male with no known systemic illness presented with defective vision in the right eye (OD) accidentally noticed following a trivial injury. He was a known case of right lacrimal gland pleomorphic adenoma with a transformation to adenocarcinoma and underwent right lacrimal gland removal and adjuvant radiotherapy (intensity-modulated radiotherapy, dose 54 Gy, 27 fractions) 17 months back. OD examination showed a best corrected visual acuity (BCVA) of 6/9 N6, mild ptosis, and a normal anterior segment with a clear lens. OD fundus examination revealed microaneurysms, cotton wool spots, hemorrhages, and macular edema. Fig. 1a and b. Left eye examination was normal with a BCVA of 6/6.Figure 1: (a) depicts the true color fundus photo of right eye (OD) showing microaneurysms and cotton wool spots, similar to diabetic retinopathy and a dull foveal reflex. (b) shows normal fundus in left eye (OS). (c) is the OD FFA image showing microaneurysms and areas of capillary nonperfusion, and (d) is the OD OCT image depicting macular edema. (e) is the external photograph of the patient showing radiation-induced ptosis in ODWhat is Your Next Step? Computed tomography of orbit to look for residual tumor No systemic investigations, proceed with retinal imaging followed by OD anti-VEGF (vascular endothelial growth factor) injection Carotid Doppler to rule out ocular ischemic syndrome Investigations to find the etiology of retinal vascular occlusion – complete blood count, coagulation profile, and vasculitis profile. Findings OD FFA showed microaneurysms and hypo fluorescent areas due to capillary closure, a characteristic feature of radiation retinopathy Fig. 1c. OCT showed significant macular edema Fig. 1d. Despite mimicking diabetic retinopathy, history of radiation exposure and the laterality, radiation-induced ptosis Fig. 1e, and clinical with imaging findings all clinched the diagnosis of radiation retinopathy. The patient was suggested intravitreal anti-VEGF injection for macular edema. Diagnosis Radiation retinopathy Correct Answer B. No systemic investigations, proceed with retinal imaging followed by OD anti-VEGF (vascular endothelial growth factor) injection. Discussion Radiation retinopathy (RR) is a slowly progressive, retinal vascular occlusive microangiopathy (endothelial insult) predominantly affecting the posterior pole (more radiosensitive), with variable latency (1.5–3 years) after radiation exposure.1–3 Factors influencing RR include radiation-related factors (type/modality/dose/fractionation), volume of retina radiated, tumor distance to optic disc, young age, diabetes mellitus, hypertension, and concurrent chemotherapy.2,3 Findings include microaneurysms, cotton wool spots, retinal hemorrhages, capillary nonperfusion, and macular edema (ME) followed by proliferative disease.1–3 It has been reported in patients undergoing intraocular irradiation (melanoma/retinoblastoma) and orbital/periorbital/facial/nasopharyngeal/intracranial irradiation.2 Decreased vision secondary to ME is the earliest symptom. Treatment involves anti-VEGF injections for ME and panretinal photocoagulation for neovascularization.1–3 Preventive measures include focused delivery, reduced total dose (<45 Gy), and hyperfractionation.2,3 Financial support and sponsorship: Nil. Conflicts of interest: There are no conflicts of interest.
Shankar et al. (Thu,) studied this question.