I thank Drs Parsa and Hoyt and Drs Jampol and Marmor for their interest in the recent case report published in the October 1998 issue of the ARCHIVES.1 Drs Parsa and Hoyt consider the arterial loops observed after central retinal artery obstruction as Nettleship collaterals. These collaterals have been reported by Ragge and Hoyt2 and Muci-Mendoza et al3 as circumpapillary multiple cilioretinal anastomoses. Marmor et al4 reported cilioretinal collateral circulation after occlusion of the central retinal artery in 2 patients, 1 of whom remained asymptomatic. Both clinical characteristics and pattern of the vascular changes seemed quite different in these reports than in the case published recently; ie, a well-demarcated arterial loop developed in the inferior edge of the disc in a patient with tilted optic disc syndrome after occlusion of the central retinal artery.
Cohen SY. All Prepapillary Arterial Loops Are Not Alike. Arch Ophthalmol. 1999;117(7):978-979. doi: