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Relating to a commissure.


Relating to a commissure.


(kom'i-shur?) [ commissura]
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?i-shur'al), adjective

anterior commissure

A symmetric axon tract running transversely through the lamina terminalis and connecting the right and left temporal cortices.

commissure of the fornix

Hippocampal commissure.

Gudden inferior commissure

See: Gudden inferior commissure

habenular commissure

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 commissure

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.
Synonym: commissure of fornix

Meynert commissure

See: Meynert commissure

palpebral commissure

The union of the upper and lower eyelids at each end of the palpebral fissure.

posterior commissure

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.

posterior commissure of spinal cord

The gray commissure connecting the halves of the spinal cord, lying behind the central canal.

tectal commissure

A symmetric axon tract running transversely through the ventral tectum of the midbrain and interconnecting the right and left superior colliculi.
References in periodicals archive ?
paired ovules, not attached to the parent plant, slender, with exposed one or two commissural ribs or ribbing along the entire length.
Aortic rheumatic heart disease commonly shows commissural fusion.
Two reports have noted gross commissural fusion in patients with ergotamine exposure), (18,19) a finding distinctly unusual for fen-phen valve disease.
Possible mechanism of this pulmonary valve hematoma is sub endothelial bleeding following pulmonary commissural laceration induced by balloon dilation and development of localized fibrosis.
Two morphologic phenotypes of BAVs were identified depending on the commissural orientation and cusp position in the parasternal short axis view (20); if cusp orientation was anterior and posterior as type 1 and cusp orientation was left and right as type 2.
Although revered and time-honored, this scoring system has recently come under intense scrutiny, chiefly after an emerging body of literature emphasized the key role of commissural calcification and subvalvular affection in determining a 'poor' procedural outcome (17, 18).
On the other hand, commissural calcification, significant subvalvular affection, in the presence of other unfavorable clinical characteristics would invite early surgical intervention.
It was also shown the right commissural distance to be the greatest, followed by the non-coronary and the left commissural ones (F=3.
Upon examination of the valves with scanning electron microscope, the endothelium forming the valves was found to be altered especially at the commissural localization.
Commissural fusion, leaflet thickening and alteration of the subvalvular apparatus are dominant mechanisms causing clinically important mitral stenosis of rheumatic origin (10).