Two Cases of Proliferative Diabetic Retinopathy with Marked Sheathing of the Retinal Arteries following Vitrectomy

Purpose: The aim of this paper was to report 2 patients (3 eyes) with proliferative diabetic retinopathy (PDR) who showed marked sheathing of the retinal arterioles that was ultimately attributed to calcification following vitrectomy. Cases: Case 1 involved a 65-year-old female with PDR who underwent bilateral vitrectomy for traction retinal detachment. Postoperatively, bilateral retinal redetachment (reRD) was observed. Sheathing of the retinal arterioles was observed at the same time, yet was not apparent preoperatively. Case 2 involved a 71-year-old female with PDR who underwent vitrectomy for vitreous hemorrhage. Postoperatively, reRD was observed, and fundus findings showed sheathing of the retinal arterioles. In both patients, silicone oil tamponade and retinopexy were performed at reoperation, but sheathing of the retinal arterioles persisted postoperatively. Fluorescein fundus angiography showed that retinal blood flow was maintained, and no vessel leakage occurred. In addition, no sheathing of the retinal veins was observed. Optical coherence tomography (OCT) showed a higher intensity for retinal arterioles with sheathing than for normal retinal arterioles. Conclusion: Vessel sheathing in our 2 patients (3 eyes) differed from the sheathing seen in vasculitis. Based on the hyperintensity on OCT, this sheathing may have been due to retinal artery calcification induced by hypoxia and inflammation associated with reRD.