Fig. 4
From: Comparative study on optic disc features of premature infants and full‐term newborns
The shape of optic disc and optic disc scleral ring. a Optic disc scleral ring acyclic. b Optic disc scleral single ring. c Optic disc scleral ring double loop. d Disc sclera hybrid ring (single-double). The optic disc was surrounded by a double ring (blue arrow). e Disc scleral ring hybrid (single-none). Double rings were seen locally on the temporal side of the optic disc (blue arrow), and the rest were single rings (black arrow)