Natural history of spontaneous intracranial hypotension: a clinical and imaging study

Abstract

BackgroundAlthough spontaneous intracranial hypotension (SIH) is well studied, there are few studies of the clinical and imaging history of SIH without interventional treatments. For example, what is the natural history of those who are untreated or treated only with conservative measures?ObjectiveTo conduct a retrospective study examining changes in imaging findings for patients with SIH without interventional treatments and to study associations between imaging findings and clinical symptoms.MethodsIncluded patients had a clinical diagnosis of SIH, were seen at Mayo Clinic between 1999 and 2021, had a brain MRI scan indicating SIH (Bern score), and had a brain MRI scan 6 or more months later without intervening leak-related interventional treatment. Bern scores were assigned for the first and last MRI scans prior to treatment. Patients were also grouped into three qualitative categories: overall improvement of symptoms, stable symptoms, or worsened symptoms based on patient report during the clinical visit at the time of the follow-up brain MRI scan.ResultsAmong 46 patients with untreated SIH, the Bern score improved over time in 11 (24%), was stable in 30 (65%), and worsened in 5 (11%). Two patients (4.3%) showed complete resolution of all abnormalities by the Bern scoring criteria. Symptoms improved in 7 (15%), were stable in 29 (63%), and worsened in 10 (22%).ConclusionsIn patients with brain MRI evidence of SIH, almost 25% demonstrated radiographic improvement, and 15% reported clinical improvement, during at least 6 months of observation or conservative treatment. Most had stable, persistent MRI abnormalities and symptoms when SIH was untreated.

Relationship of Bern Score, Spinal Elastance, and Opening Pressure in Patients With Spontaneous Intracranial Hypotension

“…Prolongation of CSF leak has previously been shown to decrease the frequency of 3 core clinical findings that would otherwise facilitate a correct diagnosis of CSF leak: the occurrence of orthostatic features in the accompanying headache; the occurrence of abnormally low OP, and the detection of pachymeningeal enhancement on brain MRI. 2,[4][5][6][7][8] In this context, our finding that patients in whom a leak was found by dCTM had statistically significantly shorter symptom duration raises the question of whether the sensitivity of dCTM has a similar time-dependent function with decreasing sensitivity over time or if the longer duration of symptoms among patients with a negative dCTM reflects a true association between symptom duration and lower probability of ongoing CSF leak. Future work should address these clinically relevant questions.…”

“…1 Prior work has shown that with an increased duration of a CSF leak, head pain is less likely to be orthostatic, opening pressure (OP) is less likely to be low, and brain MRI is less likely to show obvious features of intracranial hypovolemia. [2][3][4][5][6][7][8] As these imaging and clinical features become less conspicuous, delayed or misdiagnosis of SIH is more likely to occur, which can lead to significant morbidity, including both delays in effective treatments and exposure to inappropriate treatments and procedures. 9 In this setting, the tools used to detect CSF leak are evolving.…”

Acquired tonsillar herniation related to spontaneous intracranial hypotension: case reports

“…Typically, CSF pressure of SIH patients is very low, sometimes it is unmeasurable, but occasionally is even consistently within normal limits. Fortunately, more and more cases of SIH than before have been diagnosed with the help of MRI scan ( 14 ). Cranial MRI of SIH patients may reveal the following abnormalities, including subdural fluid collection, diffuse pachymeningeal enhancement, decreased ventricular size, enlarged pituitary, as well as engorged cerebral venous sinuses.…”

Beyond myths: Transformative insights into spinal cerebrospinal fluid leaks and their role in persistent headache syndromes

“…Adding to the clinical confusion is the fact that as time persists, the classic orthostatic nature of the headache may dissipate. 16,17 In "Management and Outcomes of Persistent Headache after Accidental Dural Puncture in the Obstetric Population: A 9-Year Prospective Audit" by Niraj and Critchley, outcomes are described for a cohort of 54 patients with persistent headache dating from the time of a known unintended dural puncture. 18 The authors report the longest-term follow-up to date for such patients with an average follow-up of 5.7 years post-puncture.…”

“…Even when patients report a new and persistent orthostatic headache that dates from the time of a recognized dural puncture, there is evidence that they are not receiving care directed toward a suspected CSF leak. Adding to the clinical confusion is the fact that as time persists, the classic orthostatic nature of the headache may dissipate 16,17 . In “Management and Outcomes of Persistent Headache after Accidental Dural Puncture in the Obstetric Population: A 9‐Year Prospective Audit” by Niraj and Critchley, outcomes are described for a cohort of 54 patients with persistent headache dating from the time of a known unintended dural puncture 18 .…”