| lateral pyramidal fasciculus | Those fibres of the pyramidal tract that cross to the opposite side in the pyramidal decussation and descend in the dorsal half of the lateral funiculus of the spinal cord; they are distributed throughout the length of the spinal cord to interneurons of the zona intermedia of the spinal gray matter. See: pyramidal tract. Synonym: tractus corticospinalis lateralis, tractus pyramidalis lateralis, crossed pyramidal tract, fasciculus corticospinalis lateralis, fasciculus pyramidalis lateralis, lateral corticospinal tract, lateral pyramidal fasciculus. (05 Mar 2000) |
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| Foville's fasciculus | A slender, compact fibre bundle that connects the amygdala (amygdaloid body) with the hypothalamus and other basal forebrain regions. Originating from the amygdala, the bundle passes first caudalward in the roof of the temporal horn of the lateral ventricle; it follows the medial side of the caudate nucleus forward in the floor of the ventricle's central part (or body) until it reaches the interventricular foramen, in the posterior wall of which it curves steeply down to enter the hypothalamus, with fibres passing both rostral and caudal to the anterior commissure. Coursing caudalward in the medial part of the hypothalamus, the bundle terminates in the anterior and ventromedial hypothalamic nuclei. Synonym: stria terminalis, Foville's fasciculus, Tarin's tenia, tenia saemicircularis. (05 Mar 2000) |
| fronto-occipital fasciculus | A bundle of association fibres extending from the frontal to the occipital lobes of the cerebrum. Synonym: fasciculus occipitofrontalis, fronto-occipital fasciculus. (05 Mar 2000) |
| lenticular fasciculus | The pallidal efferent fibres that cross the internal capsule and are insinuated between the subthalamic nucleus and zona incerta; they join in the formation of the thalamic fasciculus. See: lenticular loop. Synonym: fasciculus lenticularis. (05 Mar 2000) |
| Lissauer's fasciculus | A longitudinal bundle of thin, unmyelinated and poorly myelinated fibres capping the apex of the posterior horn of the spinal gray matter, composed of posterior root fibres and short association fibres that interconnect neighboring segments of the posterior horn. Synonym: fasciculus dorsolateralis, tractus dorsolateralis, dorsolateral tract, fasciculus marginalis, Lissauer's bundle, Lissauer's column, Lissauer's fasciculus, Lissauer's marginal zone, Lissauer's tract, marginal fasciculus, Spitzka's marginal tract, Spitzka's marginal zone, Waldeyer's tract, Waldeyer's zonal layer. (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) |