| livedo reticularis | A persistent purplish network-patterned discoloration of the skin caused by dilation of capillaries and venules due to stasis or changes in underlying blood vessels including hyalinization; rarely appears as a developmental defect. Synonym: angiitis livedo reticularis, dermatopathia pigmentosa reticularis, livedo racemosa. (05 Mar 2000) |
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| livedo reticularis idiopathica | An extensive and permanent form of livedo reticularis; in rare instances associated with central arterial disease. (05 Mar 2000) |
| livedo reticularis symptomatica | A discoloration or mottling of the skin due to some demonstrable cause, such as seen in erythema ab igne, and in certain tuberculids. See: cutis marmorata. (05 Mar 2000) |
| arteriae pontis | Several small branches of the basilar artery distributed to the pons. Synonym: arteriae pontis, rami ad pontem. (05 Mar 2000) |
| brachium pontis | The largest of three paired cerebellar peduncles, composed mainly of fibres that originate in the pontine nuclei, cross the midline in the ventral part of pons, and emerge on the opposite side as a massive bundle arching dorsally along the lateral side of the pontine tegmentum into the cerebellum; its fibres are distributed chiefly to the cortex of the cerebellar hemisphere. Synonym: pedunculus cerebellaris medius, brachium pontis. (05 Mar 2000) |
| venae pontis | Several veins running transversely on the pons to join the petrosal vein. Synonym: venae pontis, veins of pons. (05 Mar 2000) |
| raphe pontis | The continuation of the raphe medullae oblongatae into the pars dorsalis (or tegmentum) pontis. (05 Mar 2000) |
| pars basilaris pontis | The large ventral part of the pons occupied by the nuclei pontis, traversed longitudinally by corticopontine, corticobulbar, and corticospinal fibres, and transversely by pontocerebellar fibres. Pontocerebellar fibres converging laterally form the middle cerebellar peduncle or brachium pontis. Synonym: pars ventralis pontis, anterior part of pons, basilar part of pons, pars basilaris pontis. (05 Mar 2000) |
| pars dorsalis pontis | The part of the pons bounded laterally by the middle cerebellar peduncles and anteriorly by the ventral part of pons; it is continuous with the tegmentum of the mesencephalon and contains long tracts such as the medial and lateral lemnisci, cranial nerve nuclei, and reticular formation. Synonym: pars dorsalis pontis, tegmentum of pons. (05 Mar 2000) |
| pars ventralis pontis | The large ventral part of the pons occupied by the nuclei pontis, traversed longitudinally by corticopontine, corticobulbar, and corticospinal fibres, and transversely by pontocerebellar fibres. Pontocerebellar fibres converging laterally form the middle cerebellar peduncle or brachium pontis. Synonym: pars ventralis pontis, anterior part of pons, basilar part of pons, pars basilaris pontis. (05 Mar 2000) |
| cisterna pontis | An upward continuation of the subarachnoid space of the spinal cord, continuous about the medulla with the cerebellomedullary cisternl; may be divided into inferior (containing roots of C.N. 9-12) and superior (containing root of C.N. 5, 7, 8) parts. Synonym: cisterna pontis. (05 Mar 2000) |
| sulcus basilaris pontis | A median groove on the ventral surface of the pons varolii in which lies the basilar artery. Synonym: sulcus basilaris pontis, basilar sulcus. (05 Mar 2000) |
| nuclei pontis | The massive gray matter filling the basilar pons. The nuclei are of fairly homogeneous architecture and project to the cortex of the contralateral cerebellar hemisphere by way of the middle cerebellar peduncle. Their main afferents come from the entire extent of the cerebral neocortex by way of the longitudinal pontine bundles (corticopontine fibres); thus, the pontine nuclei form a major way-station in the impulse conduction from the cerebral cortex of one hemisphere to the posterior lobe of the opposite cerebellum. Synonym: nuclei pontis, pontine gray matter. (05 Mar 2000) |
| fasciculi longitudinales pontis | The massive bundles of corticofugal fibres passing longitudinally through the ventral part of pons; they are composed of corticopontine, corticobulbar, and corticospinal fibres. Synonym: fasciculi longitudinales pontis, longitudinal pontine bundles. (05 Mar 2000) |
| fasciculus obliquus pontis | A bundle of fibres in the ventral surface of the pons running from the anterior mesial portion outward and backward. Synonym: fasciculus obliquus pontis, oblique bundle of pons. (05 Mar 2000) |