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Related to tentorial herniation: Cerebral herniation, tentorial notch, Uncal herniation, Tonsillar herniation
abnormal protrusion of an organ or other body structure through a defect or natural opening in a covering membrane, muscle, or bone. (See also hernia.)
caudal transtentorial herniation transtentorial herniation.
central herniation a downward shift of the brainstem and the diencephalon due to a supratentorial lesion, causing Cheyne-Stokes respirations with pinpoint nonreactive pupils.
cingulate herniation a shift of the cingulate gyrus to below the falx cerebri.
disk herniation (herniation of intervertebral disk) (herniation of nucleus pulposus) herniated disk.
tentorial herniation transtentorial herniation.
tonsillar herniation protrusion of the cerebellar tonsils through the foramen magnum.
transtentorial herniation downward displacement of medial brain structures through the tentorial notch by a supratentorial mass, exerting pressure on the underlying structures, including the brainstem; this is a life-threatening situation because of pressure on the third cranial nerve, with symptoms including dilated, nonreactive pupils, ptosis, and a decreased level of consciousness. Called also caudal transtentorial herniation, tentorial herniation, and uncal herniation.
uncal herniation transtentorial herniation.
Etymology: L, tentorium, tent, hernia, rupture
the protrusion of brain tissue into the tentorial notch, caused by increased intracranial pressure resulting from edema, hemorrhage, or a tumor. Characteristic signs are severe headache, fever, flushing, sweating, abnormal pupillary reflex, drowsiness, hypotension, and loss of consciousness. Also called transtentorial herniation.