| frontal sinus aperture | One of a pair of openings in the floor of the frontal sinuses in the nasal part of the frontal bone, through which the frontal sinuses communicate with the ethmoidal infundibulum via the frontonasal duct. Synonym: apertura sinus frontalis. (05 Mar 2000) |
|---|---|
| longitudinal sinus | See: inferior sagittal sinus, superior sagittal sinus. Longitudinal vertebral venous sinus, large, plexiform veins forming portions of the anterior internal vertebral venous plexus lying on the posterior surfaces of the vertebral bodies on either side of the posterior longitudinal ligament. Synonym: sinus vertebrales longitudinales. Luschka's sinus, venous sinus in the petrosquamous suture. (05 Mar 2000) |
| lymphatic sinus | The channels in a lymph node crossed by a reticulum of cells and fibres and bounded by littoral cells; there are subcapsular, trabecular, and medullary sinus's. Synonym: lymph sinus. Maier's sinus, an infundibuliform depression on the internal surface of the lacrimal sac which receives the lacrimal canaliculi. Marginal sinuses of placenta, discontinuous venous lakes at the margin of the placenta. (05 Mar 2000) |
| lymph sinus | The channels in a lymph node crossed by a reticulum of cells and fibres and bounded by littoral cells; there are subcapsular, trabecular, and medullary sinus's. Synonym: lymph sinus. Maier's sinus, an infundibuliform depression on the internal surface of the lacrimal sac which receives the lacrimal canaliculi. Marginal sinuses of placenta, discontinuous venous lakes at the margin of the placenta. (05 Mar 2000) |
| apex of the posterior horn | The pointed extremity of each posterior gray column or cornu of the spinal cord. Synonym: apex cornus posterioris, caput cornus, tip of posterior horn. (05 Mar 2000) |
| arcus posterior atlantis | The posterior arch of the atlas that connects the lateral masses of the atlas posteriorly, forming the posterior wall of the vertebral canal at this level. Synonym: arcus posterior atlantis. (05 Mar 2000) |
| area intercondylaris posterior tibiae | The deep notch between the tibial condyles posteriorly to which attaches the posterior cruciate ligament. Synonym: area intercondylaris posterior tibiae. (05 Mar 2000) |
| arteria alveolaris superior posterior | <anatomy, artery> Origin, 3rd part of maxillary artery within pterygopalatine fossa; distribution, molar and premolar teeth, gingiva and mucous membrane of maxillary sinus. Synonym: arteria alveolaris superior posterior, posterior alveolar artery, posterior dental artery. (05 Mar 2000) |
| arteria auricularis posterior | <anatomy, artery> Origin: posterior aspect of external carotid just above the digastric muscle; course: ascends first between parotid gland and styloid process then between cartilage of auricle and the mastoid process; branches: muscular (digastric, stylohyoid and sternocleidomastoid), glandular (parotid), stylomastoid artery, occipital and auricular; anastomoses: anterior tympanic artery (via the stylomastoid artery) and occipital artery. Synonym: arteria auricularis posterior. (05 Mar 2000) |
| arteria caecalis posterior | <anatomy, artery> Origin, ileocolic artery; distribution, posterior region of caecum. Synonym: arteria caecalis posterior. (05 Mar 2000) |
| arteria cerebelli inferior posterior | <anatomy, artery> Origin, vertebral; distribution, lateral medulla, choroid plexus of fourth ventricle, and cerebellum; anastomoses, superior cerebellar and anterior inferior cerebellar. Synonym: arteria cerebelli inferior posterior. (05 Mar 2000) |
| arteria cerebri posterior | <anatomy, artery> Formed by the bifurcation of the basilar artery; it passes around the cerebral peduncle to reach the medial aspect of the hemisphere; for descriptive purposes it is divided into three parts: 1) the precommunical part (P1 segment of clinical terminology), the part before the junction with the posterior communicating artery, supplying parts of the thalamus, hypothalamus, and midbrain; 2) the postcommunical part (P2), supplying the thalamus, cerebral peduncles, and the choroid plexuses of the lateral and third ventricles; and 3) the terminal or cortical part, supplying the cortex of the temporal (P3) and occipital (P4) lobes. Synonym: arteria cerebri posterior. (05 Mar 2000) |
| arteria choroidea posterior | <anatomy, artery> One of several choroid branches of the P2 segment of the posterior cerebral artery that supply the choroid plexus of the body of the lateral ventricle and of the third ventricle. Synonym: arteria choroidea posterior. (05 Mar 2000) |
| arteria ciliaris posterior brevis | <anatomy, artery> One of approximately seven branches of the ophthalmic artery which pass around the optic nerve to supply the eyeball. Dividing into some 15-20 branches, they penetrate the sclera adjacent to the optic nerve, supplying the choroid and ciliary processes. Anastomoses: with central retinal artery and long and anterior ciliary arteries (at the ora serrata). Synonym: arteria ciliaris posterior brevis. (05 Mar 2000) |
| arteria ciliaris posterior longa | long posterior ciliary artery |