has part has part characteristic of inheres in has modifier Abnormal ocular adnexa morphology Abnormal common tendinous ring morphology 2015-12-23T14:27:09Z Any anomaly of the ring of fibrous tissue that surrounds the optic nerve at its entrance at the apex of the orbit. The common tendinous ring, also known as the annulus of Zinn or annular tendon, is the origin for five of the seven extraocular muscles. UMLS:C4073122 Abnormality of the common tendinous ring morphology abnormal common tendinous ring