| external canthus | The angle formed by the junction of the lateral parts of the upper and lower eyelids. Synonym: angulus oculi lateralis, angulus oculi temporalis, external canthus, lateral canthus. (05 Mar 2000) |
|---|---|
| external capsule | A thin lamina of white substance separating the claustrum from the putamen. It joins the internal capsule at either extremity of the putamen, forming a capsule of white matter external to the lenticular nucleus. Synonym: capsula externa, periclaustral lamina. (05 Mar 2000) |
| external cardiac massage | Rhythmic compression of the heart between sternum and spine by depressing the lower sternum backward with the heels of the hands, the patient lying supine. Synonym: external cardiac massage. (05 Mar 2000) |
| external carotid artery | <anatomy, artery> Origin, common carotid at C-4 vertebral level; branches, superior thyroid, lingual, facial, occipital, posterior auricular, ascending pharyngeal, and terminal branches, maxillary and superficial temporal at level of neck of mandible. Synonym: arteria carotis externa. (05 Mar 2000) |
| external carotid nerves | A number of sympathetic nerve fibres conveyed via the cephalic arterial ramus of the sympathetic trunk which extends from the superior cervical ganglion to the external carotid artery, forming the external carotid plexus. Synonym: nervi carotici externi. (05 Mar 2000) |
| external carotid plexus | An autonomic plexus formed by the external carotid nerves surrounding the artery of the same name, and giving origin to a number of secondary plexus's along the branches of this artery and to branches to the carotid body. Synonym: plexus caroticus externus. (05 Mar 2000) |
| external cephalic version | Version performed entirely by external manipulation. See: cephalic version. (05 Mar 2000) |
| external collateral ligament of wrist | The ligament that extends distally from the styloid process of the radius to the carpal bones. Synonym: ligamentum collaterale carpi radiale, external collateral ligament of wrist, lateral ligament of wrist. (05 Mar 2000) |
| external conjugate | The distance in a straight line between the depression under the last spinous process of the lumbar vertebrae and the upper edge of the pubic symphysis. Synonym: Baudelocque's diameter, external conjugate diameter. (05 Mar 2000) |
| external conjugate diameter | The distance in a straight line between the depression under the last spinous process of the lumbar vertebrae and the upper edge of the pubic symphysis. Synonym: Baudelocque's diameter, external conjugate diameter. (05 Mar 2000) |
| external cuneate nucleus | A cell group lateral to the cuneate nucleus which receives posterior-root fibres corresponding to the proprioceptive innervation of the arm and hand; it projects to the cerebellum by way of the cuneocerebellar tract, and can be considered the upper-extremity equivalent of the thoracic nucleus. Synonym: nucleus cuneatus accessorius, external cuneate nucleus, lateral cuneate nucleus, Monakow's nucleus. (05 Mar 2000) |
| external defibrillator | A defibrillator that delivers its defibrillating shock through the unopened chest wall. (05 Mar 2000) |
| external dental epithelium | External enamel epithelium, the cuboidal cells of the outer layer of the odontogenic organ of a developing tooth. (05 Mar 2000) |
| external ear | Which includes the auricle and the external acoustic, or auditory, meatus; the middle ear or the tympanic cavity with its ossicles; and the internal ear or inner ear, or labyrinth, which includes the saemicircular canals, vestibule, and cochlea. See: auricle. Synonym: auris. Origin: A.S. Eare (05 Mar 2000) |
| external exudative retinopathy | See: exudative retinitis. (05 Mar 2000) |