====== Subfalcine herniation ======

The [[cingulate gyrus]] herniates under the [[falx]]. 
----
Usually asymptomatic unless [[anterior cerebral artery]] (ACA) kinks and occludes causing bifrontal infarction. Usually warns of impending [[transtentorial herniation]].

Subfalcine [[brain herniation]] is well documented in the presence of [[raised intracranial pressure]]. 

The subfalcine herniation occurs when one hemisphere swells and shifts the cingulate gyrus beneath the falx cerebri, consequently causing injury of the [[cingulate gyrus]]
((Johnson PL, Eckard DA, Chason DP, Brecheisen MA, Batnitzky S. Imaging of acquired cerebral herniations. Neuroimaging Clin N Am. 2002;12:217–228)).

{{::transtentorialherniation.png|}}
{{http://ebooks.cambridge.org/content/978/11/3968/078/3/html_chunk/Images/03816fig1_9hi-res.jpeg?400}}

===== Diagnosis =====

[[Subfalcine Herniation Diagnosis]].

===== Complications =====

contralateral hydrocephalus due to obstruction of the foramen of Monro
anterior cerebral artery (ACA) territory infarct due to compression of ACA branches
ACA infarction occurs as the cingulate sulcus extends under the falx dragging the ipsilateral anterior cerebral artery with it. If this becomes compressed against the falx occlusion can lead to a distal anterior cerebral artery infarction and thus the clinical symptom of contralateral leg weakness. 

===== Case reports =====

Shah et al. report a case of herniation occurring after decompression of bilateral chronic subdural haematomas, which did not appear to be related to high pressure. They suggest that after rapid decompression of a collection, the unsupported brain can herniate under the falx with serious consequences: 'brain-slump'
((Shah A, Choi D. Subfalcine herniation in the absence of a high pressure
collection or mass: 'brain-slump'? Br J Neurosurg. 2004 Jun;18(3):273-4. PubMed
PMID: 15327230.
))

Recovery of the corticospinal tracts injured by subfalcine herniation: a diffusion tensor tractography study
((Seo JP, Jang SH. Recovery of the corticospinal tracts injured by subfalcine
herniation: a diffusion tensor tractography study. Neural Regen Res. 2014 Jun
15;9(12):1231-3. doi: 10.4103/1673-5374.135331. PubMed PMID: 25206787; PubMed
Central PMCID: PMC4146290.
)).