Pseudoangiomatous retinal gliosis (PARG) treated with iodine plaque in patient with chronic retinal detachment

PURPOSE: To describe a case of a chronic retinal detachment complicated by the development of pre and subretinal hemorrhage secondary to a large pseudoangiomatous retinal gliosis (PARG) that interfered with retinal reattachment. After the lesion was regressed following plaque radiotherapy retinal reattachment was successfully completed. OBSERVATIONS: A 56y.o healthy man with known history of a chronic inferior rhegmatogenous retinal detachment (RD) of the left eye (OS) presented to the Bascom Palmer Eye Institute (BPEI) emergency department (ED) complaining of new floaters OS. On examination, the patient had a visual acuity of 20/30 right eye (OD) and 20/200 OS. Fundoscopic examination showed a treated tear in OD and dense vitreous hemorrhage OS. Initial B-scan ultrasonography OS showed an inferior RD with diffuse hyperechoic material in the vitreous cavity, preretinal and subretinal space most consistent with hemorrhage. Three days later the patient presented with further vision loss and a repeat B scan showed total RD and increasing subretinal hemorrhage with a solid mass like lesion. At this point, decision was made to proceed with retinal detachment repair, removal of the vitreous hemorrhage, and retina evaluation. During surgery, a total retinal detachment was encountered with poor view of the inferior retina due to a large round vascular lesion in the subretinal space with surrounding hemorrhage and clots. The retina was reattached during surgery, however, the postop was complicated by recurrence of VH, dense hyphema, increased IOP, recurrence of retinal detachment, and growth of the mass like lesion noted during surgery. Consultation with ocular oncology diagnosed the patient with secondary PARG lesion and plaque radiotherapy was given achieving remarkable regression of the lesion. After the lesion had regressed, successful retinal reattachment was achieved, and the patient had excellent visual recovery. CONCLUSION AND IMPORTANCE: PARG lesions are uncommon in particular when associated to chronic retinal detachments. This case highlights the importance of having a high clinical suspicion for the development of these lesions to diagnose them correctly and treat them aggressively with plaque radiotherapy in order to be able to manage the underlying complex retinal detachment.