====== Slit ventricle ======

====Definition====
Despite many articles on [[slit ventricle]] syndrome (SVS), accepted terminology regarding the definition of this condition is lacking. Any [[shunt]]ed individual with a severe [[headache]] disorder in the context of ventricles that are normal or smaller than normal can be said to suffer from SVS.

===== Epidemiology =====
Seen in < 12 % of all shunted patients.



===== Etiology =====
[[Overshunting]].

[[Fourth ventricle hydrocephalus]].

Some patients with [[idiopathic intracranial hypertension]], have slit -like ventricles with consistently elevated [[ICP]].

===== Pathophysiology =====

There are different pathophysiologies that are involved in the process. 

These pathologies are defined by intracranial pressure measurement.

Refers to complete collapse of the [[ventricle]]s.

In a survey a [[frontal occipital horn ratio]] < 0,2 was most often interpreted as representing [[slit ventricle syndrome]]
((O'Hayon BB, Drake JM, Ossip MG, Tuli S, Clarke M. Frontal and occipital horn
ratio: A linear estimate of ventricular size for multiple imaging modalities in
pediatric hydrocephalus. Pediatr Neurosurg. 1998 Nov;29(5):245-9. PubMed PMID:
9917541.
)).

===== Clinical =====
see [[Slit ventricle syndrome]].

===== Diagnosis =====
The shunt [[valve]] fills slowly if pumped when the ventricles are collapsed.


===== Differential Diagnosis =====
For headache consistent with migraine that are not postural, a trial with migraine-specific medications is warranted.

see [[Idiopathic intracranial hypertension treatment]].
===== Treatment =====
see [[Slit ventricle treatment]].

===== Case series =====

==== 1988 ====

Five patients with this syndrome were treated with [[antisiphon device]]s, high pressure shunts, or subtemporal decompression, but continued to be symptomatic. [[Third ventriculostomy]], performed as a last resort in these patients, gave encouraging results
((Reddy K, Fewer HD, West M, Hill NC. Slit ventricle syndrome with aqueduct
stenosis: third ventriculostomy as definitive treatment. Neurosurgery. 1988
Dec;23(6):756-9. PubMed PMID: 3216975.
)).

==== 1983 ====
Pre- and post craniectomy ventricular areas were measured from computed tomography scans with a computer digitizing technique in three patients with this syndrome who had undergone four surgical procedures. All patients improved symptomatically following [[craniectomy]]. A significant decrease in total ventricular area was noted in all instances. The results suggest that subtemporal craniectomy causes the ventricles to become smaller, not larger
((Linder M, Diehl J, Sklar FH. Subtemporal decompressions for shunt-dependent
ventricles: [[mechanism of action]]. Surg Neurol. 1983 Jun;19(6):520-3. PubMed PMID: 
6857480.
)).