| anterior clear space | On lateral chest radiographs, the region dorsal to the sternum and ventral to the ascending aorta. Synonym: anterior clear space. (05 Mar 2000) |
|---|---|
| anterior column | The pronounced, ventrally oriented ridge of gray matter in each half of the spinal cord; it corresponds to the anterior or ventral horn appearing in transverse sections of the cord, and contains the motor neurons innervating the skeletal musculature of the trunk, neck, and extremities. See: gray columns. Synonym: columna anterior. (05 Mar 2000) |
| anterior column of medulla oblongata | An elongated, white prominence on the ventral surface of the medulla oblongata on either side along the anterior median fissure, corresponding to the pyramidal tract. Synonym: pyramis medullae oblongatae, anterior column of medulla oblongata, anterior pyramid. (05 Mar 2000) |
| anterior commissure | A round bundle of nerve fibres that crosses the midline of the brain near the anterior limit of the third ventricle. It consists of a smaller anterior part, the fibres of which pass in part to the olfactory bulbs, and a larger posterior part, which interconnects the left and right temporal lobes. Synonym: commissura anterior. (05 Mar 2000) |
| anterior communicating artery | <anatomy, artery> A short vessel joining the two anterior cerebral arteries and completing the cerebral arterial circle (circle of Willis) anteriorly. Synonym: arteria communicans anterior. (05 Mar 2000) |
| anterior compartment syndrome | <syndrome> Rapid swelling, increased tension, pain, and ischemic necrosis of the muscles of the anterior tibial compartment of the leg, often following excessive exertion. (12 Dec 1998) |
| anterior component of force | A force operating to move teeth anteriorly. (05 Mar 2000) |
| anterior condyloid canal of occipital bone | The canal through which the hypoglossal nerve emerges from the skull. Synonym: canalis hypoglossalis, anterior condyloid canal of occipital bone, anterior condyloid foramen. (05 Mar 2000) |
| anterior condyloid foramen | The canal through which the hypoglossal nerve emerges from the skull. Synonym: canalis hypoglossalis, anterior condyloid canal of occipital bone, anterior condyloid foramen. (05 Mar 2000) |
| anterior conjunctival artery | <anatomy, artery> One of a number of small branches of the anterior ciliary arteries that supplies the conjunctiva. Synonym: arteria conjunctivalis anterior, conjunctival arteries. (05 Mar 2000) |
| anterior coronary plexus | The part of the cardiac plexus that accompanies the coronary arteries on the anterior aspect of the heart. (05 Mar 2000) |
| anterior corticospinal tract | Uncrossed fibres forming a small bundle in the pyramidal tract. See: pyramidal tract. Synonym: tractus corticospinalis anterior, tractus pyramidalis anterior, anterior corticospinal tract, anterior pyramidal fasciculus, direct pyramidal tract, fasciculus corticospinalis anterior, fasciculus pyramidalis anterior, Turck's bundle, Turck's column, Turck's tract. (05 Mar 2000) |
| anterior costotransverse ligament | <anatomy> The fibrous band that extends upward from the neck of a rib to the transverse process of the next higher vertebra. Synonym: ligamentum costotransversarium superius, anterior costotransverse ligament, ligamentum costotransversarium anterius. (05 Mar 2000) |
| anterior cranial base | The portion of the internal base of the skull, anterior to the sphenoidal ridges and limbus, in which the frontal lobes of the brain rest. Synonym: fossa cranii anterior, anterior cranial base. (05 Mar 2000) |
| anterior cranial fossa | The portion of the internal base of the skull, anterior to the sphenoidal ridges and limbus, in which the frontal lobes of the brain rest. Synonym: fossa cranii anterior, anterior cranial base. (05 Mar 2000) |