| orbital sulci | A number of irregularly disposed, variable sulci dividing the inferior or orbital surface of each frontal lobe of the cerebrum into the orbital gyri. Synonym: sulci orbitales. (05 Mar 2000) |
|---|---|
| orbital surface | The surface of a bone which contributes to the walls of the orbit. The NA recognises an orbital surface on the following bones: greater wing of the sphenoid bone; the maxilla; the frontal bone; the zygomatic bone. Synonym: facies orbitalis. (05 Mar 2000) |
| orbital syndrome | <syndrome> An obsolete term referring to neoplastic tissue formation involving the apex of the orbit, causing ophthalmoplegia and optic nerve atrophy. (05 Mar 2000) |
| orbital tubercle of zygomatic bone | A small elevation on the orbital surface of the zygomatic bone, just within the orbital margin, about 1 cm below the zygomaticofrontal suture; it gives attachment to the lateral check ligament, the lateral palpebral ligament, and the suspensory ligament of the eyeball. Synonym: eminentia orbitalis ossis zygomatici, orbital eminence of zygomatic bone, Whitnall's tubercle. (05 Mar 2000) |
| orbital width | The distance between the dacryon and the farthest point on the anterior edge of the outer border of the orbit (Broca), or between the latter point and the junction of the frontolacrimal suture and the posterior edge of the lacrimal groove. (05 Mar 2000) |
| tarso-orbital | Relating to the eyelids and the orbit. (05 Mar 2000) |
| zygomatico-orbital | Relating to the zygomatic bone and the orbit. (05 Mar 2000) |
| zygomatico-orbital artery | <anatomy, artery> Origin, superficial temporal, sometimes middle temporal; distribution, orbicularis oculi muscle and portions of the orbit; anastomoses, lacrimal and palpebral branches of ophthalmic. Synonym: arteria zygomatico-orbitalis. (05 Mar 2000) |
| zygomatico-orbital foramen | The common opening on the orbital surface of the zygomatic bone of the canals transmitting the zygomaticofacial and zygomaticotemporal nerves; sometimes each of these canals has a separate opening on the orbital surface. Synonym: foramen zygomatico-orbitale. (05 Mar 2000) |
| fronto-orbital area | The cerebral cortex covering the basal surface of the frontal lobes. Synonym: fronto-orbital area. (05 Mar 2000) |
| acoustic crest | An elevation on the inner surface of the ampulla of each saemicircular duct; filaments of the vestibular nerve pass through the crista to reach hair cells on its surface; the hair cells are capped by the cupula, a gelatinous protein-polysaccharide mass. Synonym: crista ampullaris, acoustic crest, transverse septum. (05 Mar 2000) |
| acousticofacial crest | The part of the neural crest from which the ganglia of the seventh and eighth cranial nerves develop. (05 Mar 2000) |
| alveolar crest | The portion of the alveolar bone extending beyond the periphery of the socket, lying interproximally, the top of the residual alveolar bone. (05 Mar 2000) |
| ampullary crest | An elevation on the inner surface of the ampulla of each saemicircular duct; filaments of the vestibular nerve pass through the crista to reach hair cells on its surface; the hair cells are capped by the cupula, a gelatinous protein-polysaccharide mass. Synonym: crista ampullaris, acoustic crest, transverse septum. (05 Mar 2000) |
| anterior lacrimal crest | A vertical ridge on the lateral surface of the frontal process of the maxilla that forms part of the medial rim of the orbit. Synonym: crista lacrimalis anterior. (05 Mar 2000) |