| crossed knee reflex | Contraction of the contralateral quadriceps when a patellar reflex is elicited. Synonym: crossed knee jerk. (05 Mar 2000) |
|---|---|
| crossed paralysis | alternating hemiplegia |
| crossed phrenic phenomenon | Hemisection of the cord above the exit of the phrenic nerve paralyzes the ipsilateral half of the diaphragm; if the contralateral phrenic nerve is then sectioned or blocked, contractions on the ipsilateral side are resumed. (05 Mar 2000) |
| crossed pyramidal tract | 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) |
| crossed reflex | A reflex movement on one side of the body in response to a stimulus applied to the opposite side. Synonym: crossed jerk. (05 Mar 2000) |
| crossed reflex of pelvis | Contraction of the contralateral adductors of the thigh upon tapping the anterior superior iliac spine. Synonym: crossed spino-adductor reflex. (05 Mar 2000) |
| crossed renal ectopia | <radiology> M more than F, right (67%), may fuse: crossed-fused renal ectopia (12 Dec 1998) |
| crossed spino-adductor reflex | Contraction of the contralateral adductors of the thigh upon tapping the anterior superior iliac spine. Synonym: crossed spino-adductor reflex. (05 Mar 2000) |
| crossed testicular ectopia | Testis that has crossed the midline to join its contralateral mate in the contralateral inguinal canal or hemiscrotum. (05 Mar 2000) |
| embolism, crossed | See Embolism, paradoxical. (12 Dec 1998) |
| achromatic lens | A compound lens made of two or more lens's having different indices of refraction, so correlated as to minimise chromatic aberration. (05 Mar 2000) |
| acoustic lens | In ultrasonography, a lens used to focus or diverge a sound beam; may be simulated by electronic manipulation of signals. (05 Mar 2000) |
| anterior pole of lens | The central point on the anterior surface of the lens of the eye. Synonym: polus anterior lentis. (05 Mar 2000) |
| anterior surface of lens | The anterior surface of the lens of the eye. Synonym: facies anterior lentis. (05 Mar 2000) |
| aplanatic lens | A lens designed to correct spherical aberration and coma (q.v.). Synonym: periscopic meniscus. (05 Mar 2000) |