Early signs of uncal herniation include encroachment on the suprasellar cistern, displacement of the brain stem, enlargement of the ipsilateral crural subarachnoid space, and compression of the contralateral cerebral peduncle. Ascending transtentorial herniation radiology case. Descending transtentorial herniartion dth secondary to a supratentorial mass effect can be detected by ct. Uncal herniation definition of uncal herniation by. Diagnosis of descending transtentorial herniation by. Cerebral herniation, also referred to as acquired intracranial herniation, refers to shift of cerebral tissue from its normal location, into an adjacent space as a result of mass effect. Transalar herniation is not as common as the other types of brain herniation. Ascending transtentorial herniation radiology reference. This type of brain herniation can be further broken down into two types. The author of this video presents transtentorial herniation.
Transtentorial herniation definition of transtentorial. Mri demonstrates descending transtentorial herniation. Brain herniation is what its called when some some brain tissue moves outside of the skull, or moves across or into a structure with the skull. Cushings triad is response to diminished brain stem perfusion, regardless of etiology. Downward transtentorial central and uncal herniations. Transtentorial herniation can occur when the brain moves either up or down across the tentorium, called ascending and descending transtentorial herniation respectively. The opening in the tentorium through which the brainstem, specifically the midbrain, connects to the cerebrum is the tentorial incisura. Ecr 2019 c2732 imaging evaluation of the intracranial herniation. Transtentorial herniation has been investigated with computed tomography using the three calcification relationship and descent through the tentorial opening could not be documented. Feel free to comment and suggest what you would like to see in the future, and i will do my best to fulfill those. These structures are frequently damaged during transtentorial herniation, leading to a chain of often irreversible, secondary injuries.
Ascending transtentorial herniation is a situation where spaceoccupying lesions in the posterior cranial fossa cause superior displacement of superior parts of the cerebellum through the tentorial notch. Compression of the third cranial nerve and brainstem results in pathognomonic signs of pupillary dilatation, hemiparesis, and loss of consciousness. There is a direct link through which you can view, download, print. Radiological assessment should be performed to identify the underlying pathology. Early recognition of brain herniation based on clinical signs, such as failure to arouse and dilated pupils after surgery, should alert clinicians that brain herniation may have occurred. In uncal herniation, a common subtype of transtentorial herniation, the innermost part of the. This is usually caused by a rapidly expanding middle cranial fossa epidural, subdural, or intratemporal lobe hematoma.
The following text describes the various clinical signs to recognize this condition and the possible measures one can take to treat it. Mri images show extensive infarct in the bilateral cerebellar hemispheres with mass effect and ascending transtentorial herniation that has resulted in the obliteration of quadrigeminal and superior cerebellar cisterns. Transtentorial herniation by finney, louis arthur, 1931. It often occurs in combination with subfalcine and transtentorial herniatio n. Koenig ma1, bryan m, lewin jl 3rd, mirski ma, geocadin rg, stevens rd. Dr daniel bryant dicapua is an assistant professor of neurology at yale school of medicine. In this video he discusses the key features of brain herniation. Earl arthur earl, 1907publication date 1962 topics brain publisher springfield, ill. Bilateral brain stem compression in acute bilateral cases must be distinguished from herniation. Downward herniation can stretch branches of the basilar artery pontine arteries. Transtentorial herniation is a serious consequence of supratentorial edemamass lesions in patients with tbi. Descending transalar herniation occurs as a result of frontal lobe mass effect. In each patient, coma with reactive, miotic pupils, asymmetrical or absent caloric responses, and decerebrate posture indicated brainstem compression. A 68 yearold woman with a known glioblastoma multiforme presented with approximately one week of confusion and drowsiness.
Brain herniation occurs with an increase in intracranial pressure and brain swelling, causing compression of the lateral ventricle and compression of the cardiac and respiratory centers. Uncal herniation is an early or unilateral descending transtentorial herniation that occurs when innermost portion of temporal lobe, the uncus is pushed over the. It is a secondary condition caused by a primary injury on the opposite hemisphere of the brain. It is a lifethreatening condition that requires prompt diagnosis. Brain herniation types, symptoms and radiology see online here brain herniation is a potentially fatal condition that may present as a rise in intracranial pressure. The condition can be inferred from clinical neurologic signs, but has not been visualized during life. There are a number of different patterns of cerebral herniation which describe the type of herniation occurring.
Neuroimaging revealed edema of the cerebellar folia with noncommunicating hydrocephalus and upward transtentorial herniation. The most common is transtentorial herniation, in which the uncus of the temporal lobe is displaced from the supratentorial to the infratentorial space. Tentorial herniation definition of tentorial herniation. Cuneo ra, caronna jj, pitts l, townsend j, winestock dp. The internal medicine lecture series is a resident founded, resident run foamed free open access medical education project. Intracranial hernias can be further divided into three types. Descending cerebral transtentorial herniation dth is a serious and often fatal complication of intracranial mass lesions. Transtentorial herniation tth is a lifethreatening neurologic condition that typically results from expansion of. Ascending transtentorial herniation, which is less common than uncal herniation. Reversal of transtentorial herniation with hypertonic saline.
Brain herniation is a potentially deadly side effect of very high pressure within the skull that. Kernohans notch is a cerebral peduncle indentation associated with some forms of transtentorial herniation uncal herniation. Types of brain herniation include central brain herniation, cerebellar tonsillar herniation, and uncal transtentorial herniation. Feel free to comment and suggest what you would like to see.
Central transtentorial herniation downward displacement of the brain through the tentorial notch incisura. The tentorium is a dural structure that separates the cerebrum from the brainstem and cerebellum in the posterior cranial fossa below. Seven cases of upward transtentorial herniation occurred. Transtentorial herniation synonyms, transtentorial herniation pronunciation, transtentorial herniation translation, english dictionary definition of transtentorial herniation. Neuroanatomydigital anatomy atlas download the app from. Excellent video regarding brain herniation and its clinical signs suitable for trainees, medical and other students original source emergencymedicineireland. Automated pupillometry and detection of clinical transtentorial. Brain herniation syndromes are commonly classified on the basis of their location as intracranial and extracranial hernias.
Transtentorial herniation is a type of cerebral herniation. Examination showed wordfinding difficulty, a right homonymous hemianopsia, and right arm apraxia. Ascending transtentorial herniation signs and symptoms. Transtentorial herniation radiology reference article. While death due to medullary compression associated with herniation of the cerebellar tonsils has long been known, relatively little attention has been paid to the sequela of compression of the brain stem caused by herniation of the stem through the. Using midsagittal magnetic resonance images mris, we compared vertical brainstem position on 50 images from normals and 21 images from 15 clinically. How to treat a lumbar disc tear or disc herniation, by dr. These videos are designed for medical students studying for the usmle step 1. Brain herniation is the displacement of brain tissue through the rigid dural folds i. Transtentorial herniation occurs when brain tissue is displaced into the tentorial notch, and is perhaps the most important herniation phenomenon in terms of frequency and clinical consequences. However, with aggressive neurointensive care and neurosurgical treatments we found a 59% patient incidence of a favorable outcome. The uncus of the temporal lobe herniates over the free edge of the tentorium, compressing the midbrain and the oculomotor nerve. Upward transtentorial herniation, hydrocephalus, and.
465 907 833 408 330 905 848 595 720 1142 1360 289 1037 1359 207 953 25 724 410 556 837 1123 747 598 1221 518 1528 807 1073 579 1410 269 455 681 771 1060