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(kŏm″mĭ-sū′ră) pl. commissurae [L.] Commissure.


(kom′ĭ-shur″) [ commissura, connection, band, knot] 1. In the central nervous system, an axon tract that crosses the midline (sagittal) plane between two homologous and symmetric structures, e.g., the corpus callosum, which interconnects the right and left cerebral cortices. 2. The meeting of two structures, as the lips, eyelids, or labia, across the midline (sagittal) plane. commissural (kom″ĭ-shur′ăl), adj.

anterior c. A transverse tract that connects the right and left temporal lobes.

habenular c. A group of decussating axons of the stria medullaris. The stria medullaris contains axons projecting to the habenula from the septal nuclei, the preoptic hypothalamus, and the anterior thalamic nuclei; those stria medullaris axons that project to the contralateral habenula cross the midline plane via the habenular commissure.

hippocampal c. A thin sheet of axons from the fornix that cross the midline plane under the posterior sector of the corpus callosum and interconnect homologous fields of the right and left hippocampi. SYN: commissure of fornix.

posterior c. An axon tract running transversely through the gray matter that forms the roof of the cerebral aqueduct in the midbrain. This tract contains commissural axons interconnecting the right and left pretectal areas; it also contains decussating axons from each pretectal area to the contralateral Edinger-Westphal nucleus (accessory oculomotor nucleus).

tectal c. A symmetric axon tract running transversely through the ventral tectum of the midbrain and interconnecting the right and left superior colliculi.


(kŏm″ĭ-shūr-or′ă-fē) [″ + Gr. rhaphe, seam, ridge] The surgical joining of the parts of a commissure to decrease the size of the opening.


(kŏm″ĭ-shūr-ŏt′ō-mē) [″ + Gr. tome, incision] Surgical incision of any commissure; used, for example, to treat mitral stenosis to increase the size of the mitral orifice. This is done by incising the adhesions that cause the leaves of the valve to stick together. Commissurotomy may also be used to treat certain psychiatric conditions by incising the anterior commissure of the brain.


(kŏ-mĭt′mĕnt) The legal procedure for hospitalization of a patient who may not be competent to choose to be hospitalized. Confining a patient without his or her consent may be necessary, for example, to care for suicidal patients, patients with altered mental status, or persons with certain contagious diseases.

Committee on Accreditation for Respiratory Care

ABBR: CoARC. An accreditation agency that works with the Commission on Accreditation of Allied Health Programs to ensure the educational quality of programs that provide professional education in respiratory care. Its website is


(kŏ-mōd′) [Fr. commode, fr L. commodus, convenient] ...

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