- - a. cervicalis [TA] a loop in the cervical plexus consisting of fibers from the first three cervical nerves. Fibers from a loop between the C1 and C2 spinal nerves accompany the hypoglossal nerve for a short distance, leaving it as the superior root of the a. cervicalis. Fibers from a loop between the C2 and C3 spinal nerves form the inferior root of the a. cervicalis. Most commonly, the roots merge, forming the a. cervicalis, which gives rise to branches innervating infrahyoid muscles. SYN: cervical loop, loop of hypoglossal nerve.- Henle a. SYN: nephronic loop.- a. lenticularis [TA] SYN: lenticular loop.- ansae nervorum spinalium SYN: loops of spinal nerves, under loop.- a. peduncularis [TA] a complex fiber bundle curving around the medial edge of the internal capsule and connecting the anterior part of the temporal lobe (temporal cortex), amygdala, and olfactory cortex with the mediodorsal nucleus of the thalamus; it enters the thalamus as a component of the inferior thalamic peduncle which also contains a major part of the fibers connecting the mediodorsal nucleus to the orbitofrontal cortex. SYN: peduncular a., peduncular loop, Reil a..- a. sacralis a nerve cord connecting one or both of the sympathetic nerve trunks with the ganglion impar.- a. subclavia [TA] a nerve cord connecting the middle cervical and inferior cervical or stellate sympathetic ganglia, forming a loop around the subclavian artery. SYN: subclavian loop, Vieussens a., Vieussens loop.
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* * *n.(in anatomy) a loop; for example, the ansa hypoglossi is the loop formed by the descending branch of the hypoglossal nerve.
* * *an·sa (anґsə) gen. and pl. anґsae [L. â€œhandleâ€] a loop or looplike structure.
Medical dictionary. 2011.