Ridley's circle -->
circular sinus
medical dictionary

Dural venous formation which surrounds the hypophysis, composed of right and left cavernous sinuses and the intercavernous sinuses.

Synonyms: circulus venosus ridleyi, Ridley's circle.

A venous sinus at the periphery of the placenta.

Synonyms: sinus venosus sclerae.

(05 Mar 2000)