Spontaneous Intracranial Hypotension

Abstract

pontaneous intracranial hypotension was first described in 1938 by Georges Schaltenbrand, a neurologist in Würzburg, Germany, who named it "hypoliquorrhea" (1, 2). Isolated case reports appeared in the 1940s, and the syndrome has been described many times in print since the mid-1990s (3-9).* Schievink et al. carried out an observational study in the greater Los Angeles area to determine the incidence of SIH. 11 patients with SIH and 23 with spontaneous subarachnoid hemorrhage (SAH) were seen in an emergency department (10, 11). On the basis of an assumed incidence of 10 cases of SAH per 100 000 persons per year, an annual incidence of 5 SIH cases per 100 000 persons was derived.In our neurosurgery department, the number of referrals of patients with SIH and the corresponding catchment area have grown steadily larger: 25 patients with SIH were treated in 2016 and another 25 in 2017, 35 in 2018, and 89 in 2019. Women are affected twice as commonly as men; the average age of onset is 40 years (7,(11)(12).The condition is pathogenetically separated from that of postlumbar puncture headache and from postoperative cerebrospinal fluid (CSF) loss (13). Clinical differential diagnoses include postural orthostatic tachycardia syndrome (POTS), Chiari I malformation, and cervicogenic headache (12, 13). Clinical featuresThe most prominent symptom is positionally dependent headache that is worse in the standing position and tends to increase in severity over the course of the day. Rapid onset is typical: most patients can identify "the day it all began" (14, 15). The positional dependence of the headache, and its being most pronounced in the back of the head, can be explained as the result of the the following causal sequence: low CSF volume-sagging of the brain-tension on the cranial nerves and dura mater. The dura mater of the posterior fossa is especially sensitive to tension (14).

Incidence of spontaneous intracranial hypotension in a community: Beverly Hills, California, 2006–2020

“…It is now well-recognized that spontaneous intracranial hypotension (SIH) is an important cause of new-onset daily headaches, particularly in young and middle-aged individuals (1–6). An orthostatic headache, i.e., a headache that is exacerbated by the upright position, is the prototypical manifestation of SIH, but the positional component often becomes less recognizable with the passage of time (1–6).…”

“…It is now well-recognized that spontaneous intracranial hypotension (SIH) is an important cause of new-onset daily headaches, particularly in young and middle-aged individuals (1–6). An orthostatic headache, i.e., a headache that is exacerbated by the upright position, is the prototypical manifestation of SIH, but the positional component often becomes less recognizable with the passage of time (1–6). Spontaneous intracranial hypotension may also cause various other more or less serious neurologic manifestations such as hearing loss, dizziness, diplopia, nuchal rigidity, coma, and bibrachial amyotrophy (1–6).…”

Support Vector Machine-based Spontaneous Intracranial Hypotension Detection on Brain MRI

“…In this study, we showed the feasibility of an automated approach of classifying head MRI scans to identify patients with spontaneous intracranial hypotension (SIH). A single MRI sequence, namely a contrast-enhanced T1-weighted MPRAGE sequence, which is part of our standard MRI protocol was analyzed [ 11 ]. As the segmentation of the considered volumes (superior sagittal sinus, both transverse sinuses, suprasellar cistern) is done by a computer there is no variability between raters allowing for an objective and unbiassed MRI assessment.…”

Spontaneous intracranial hypotension: diagnostic and therapeutic workup

“…The goal is to locate the ventral dural tear by exactly locating the point of egress of iodinated contrast medium into the epidural space. This is achieved with the iodinated contrast medium slowing flowing into a caudo-cranial direction on the ventral side of the subarachnoid space [25][26][27] (Fig. 2).…”