Central herniation is the subtype of downward transtentorial herniation of the brain that involves descent of the diencephalon and midbrain. It usually occurs with other types of downward herniation such as uncal herniation.
The clinical syndrome of central herniation classically manifests as a rostral to caudal progression of deficits attributed to brainstem dysfunction, including cranial nerve III (oculomotor nerve) palsy, diminished level of consciousness, decerebrate or decorticate posturing, rigidity or paralysis, abnormal respiratory pattern, and eventually death.
Central herniation is a late/severe sequela of supratentorial mass effect, especially when bilateral or midline. Potential etiologies include neoplasms, severe cerebral edema (e.g. from acute infarct), hemorrhage, and hydrocephalus.
Cross-sectional imaging (CT or MRI) demonstrates the following abnormalities 1,2:
- effacement of the perimesencephalic cisterns (most common finding)
- descent (caudal displacement through the tentorial hiatus) of the diencephalon, usually along with herniation of both temporal lobes (lateral herniation)
- oblong deformity of the midbrain
- descent of the quadrigeminal plate
- descent of the basilar artery
- flattening of the ventral pons against the clivus
Complications of central herniation include the following 2:
- Duret hemorrhage due to shearing of basilar artery perforator branches
- infarction of the posterior cerebral artery territory
- hydrocephalus due to obstruction of the cerebral aqueduct
- 1. Motoyama Y, Nakajima T, Takamura Y, Nakazawa T, Wajima D, Takeshima Y, Matsuda R, Tamura K, Yamada S, Yokota H, Nakagawa I, Nishimura F, Park YS, Nakamura M, Nakase H. Risk of brain herniation after craniotomy with lumbar spinal drainage: a propensity score analysis. (2018) Journal of neurosurgery. doi:10.3171/2017.12.JNS172215 - Pubmed
- 2. Riveros Gilardi B, Muñoz López JI, Hernández Villegas AC, Garay Mora JA, Rico Rodríguez OC, Chávez Appendini R, De la Mora Malváez M, Higuera Calleja JA. Types of Cerebral Herniation and Their Imaging Features. (2019) Radiographics : a review publication of the Radiological Society of North America, Inc. 39 (6): 1598-1610. doi:10.1148/rg.2019190018 - Pubmed