Spontaneous Intracranial Hypotension Research Articles

Real-life study of the use of oto-acoustic emissions in the diagnosis of intracranial hypotension

BackgroundThe diagnosis of spontaneous or post-traumatic intracranial hypotension (IH) mainly relies on clinical features and neuro-imaging. However, the results of brain and spine magnetic resonance imaging are not always contributive. There is an interest for other non-invasive procedures, able to confirm or refute the diagnosis. The use of oto-acoustic emissions (OAE) was previously reported on isolated cases of IH associated with endolymphatic hydrops (ELH). The aim of this study was to assess the real-life utilization of this electrophysiological method in a larger population of suspected IH. MethodsA retro-prospective cohort study was conducted from November 2013 to July 2022 in patients with a suspected or doubtful diagnosis of IH. They were assessed for ELH by recording bilateral distortion product of oto-acoustic emissions (DPOAE) in sitting then in supine position. ResultsAmong the 32 patients assessed, the diagnostic of IH was confirmed in 18 patients. An ELH was shown in 15 of them (83%), but also in seven other patients. They had several differential diagnoses: chronic migraine, Chiari malformation, rebound intracranial hypertension and perilymph fistula. ConclusionsThis procedure seems to be insufficient to exclude differential diagnosis when intracranial hypotension is suspected.

Distinct Pattern of Membrane Formation With Spinal Cerebrospinal Fluid Leaks in Spontaneous Intracranial Hypotension.

To systematically describe pertinent, intraoperative anatomic findings encountered when approaching spinal cerebrospinal fluid (CSF) leaks and CSF-venous fistulas in spontaneous intracranial hypotension (SIH). In a retrospective study, we included surgically treated patients suffering from SIH at our institution from April 2018 to March 2022. Anatomic, intraoperative data were extracted from operative notes and supplemented with data from surgical videos and images. Prominent anatomic features were compared among different types of CSF leaks. The study cohort consists of 120 patients with a mean age of 45.2 years. We found four distinct patterns of spinal membranes specifically associated with different types of CSF leaks: (i) thick, dorsal membranes, which were hypervascular and may mimic the dura (pseudodura); (ii) thin, lateral membranes encapsulating a ventral epidural CSF compartment (confining the spinal longitudinal extradural CSF collection); (iii) ventral membranes constituting a transdural funnel-like CSF channel; and (iv) lateral membranes forming spinal cysts/meningeal diverticulae associated with lateral CSF leaks. The latter three types resemble a layer of arachnoid herniated through the dural defect. We describe four distinct spinal (neo-)membranes in association with spinal CSF leaks. Formation of these membranes, or emergence by herniation of arachnoid through a dural defect, constitutes a specific pathoanatomic feature of patients with SIH and CSF leaks. Recognition of these membranes is of paramount importance for diagnosis and treatment of patients with spinal CSF leaks.

Multiple skull base defects in the setting of spontaneous cerebrospinal fluid rhinorrhea; a dual institution view

PurposeIdiopathic intracranial hypertension (IIH) is a condition of high cerebrospinal fluid (CSF) pressure that presents with CSF leak. The implications of multiple skull base defects (SBD) and associated synchronous CSF leaks have not been previously explored. Materials and methodsA dual institutional case-control study examined multiple SBD's and encephaloceles on the risk of CSF leak and postoperative failures post-repair. IIH patients with CSF leaks and IIH controls without leaks were selected retrospectively. Chi square analysis evaluated for statistically significant alterations in probability with CSF leak development. Results192 patients were selected with 108 IIH controls and 84 spontaneous CSF leak cases. Signs and symptoms for IIH controls and CSF leak cases respectively were pulsatile tinnitus (60.2 % and 29.8 %), headaches (96.3 % and 63.1 %), papilledema (74.1 % and 12.5 %), visual field defects (60.8 % and 13 %) (p < 0.001). Encephalocele formation in controls was 3.7 % compared to cases at 91.6 % (p < 0.001). Multiple SBD's in controls compared cases was 0.9 % and 46.4 % respectively (p < 0.001). Subgroup analysis of CSF leak cases showed 15 patients with two CSF leak repairs due to a recurrence. 27 (39.1 %) single leak cases had multiple SDB's while 12 (80 %) recurrent leaks had multiple SDB's (p = 0.004). ConclusionsPatients with radiographic evidence of multiple SBD's and encephaloceles represent a high-risk population with a propensity for CSF leaks. Secondary SBD's are common in patients with spontaneous CSF rhinorrhea and higher in patients with a recurrence.

Spontaneous Intracranial Hypotension Complicated by a Cerebral Venous Thrombosis Following an mRNA Covid-19 Vaccination: Coincidence vs Cause?

Spontaneous intracranial hypotension is rarely complicated by cerebral venous thrombosis (CVT).The majority of cerebral venous thrombosis cases post-COVID-19 vaccination occurred in patients administered with adenoviral vaccines. CVT following administration of mRNA COVID-19 vaccines is rare.Clinicians should consider COVID-19 vaccine-induced CVT in recently vaccinated patients; MRI plays an important role in accurate diagnosis.

Spontaneous Intracranial Hypotension: A Review of Neuroimaging and Current Concepts.

Spontaneous intracranial hypotension (SICH) is the emerging cause of orthostatic headache as it has been better recognized in recent years. SICH happens due to spinal cerebrospinal fluid (CSF) leak; however, the manifestations are predominantly cranial and hence imaging in SICH includes brain and spine. There are few characteristic brain imaging features to be concerned about to diagnose SICH in patients with vague symptoms or low clinical suspicion. Spine screening is recommended in these patients to assess spinal CSF leaks. While neuroradiologists play a significant role from the time of diagnosis to treatment of SICH, there is a need for all the general radiologists to be aware of the condition. Computed tomography myelogram and digital subtraction myelogram are performed for diagnostic and therapeutic management of SICH. There is a known risk for SICH recurrence in patients with sagittal longitudinal epidural collection and hence, targeted blood patch should be used instead of blind patch. Most importantly, slow mobilization is recommended following the patch to avoid recurrence.

Spontaneous intracranial hypotension: a case report in the context of differential diagnosis of chronic headaches

Spontaneous intracranial hypotension (SIH) is a rare and debilitating condition caused by decreased intracranial pressure, which occurs more frequently in females. SIH can have several causes, among them the spontaneous formation of cerebrospinal fluid venous fistula (CSF-venous fistula), which is primarily responsible for the appearance of postural headache. Orthostatic headache is diagnosed by CSF pressure &lt; 6 mmHg associated with specific imaging findings. Other specific symptoms such as dizziness, reduced muscle strength, blurred vision and syncope and other more systemic symptoms such as fatigue, mental confusion and difficulty concentrating are commonly observed. Etiological investigation through imaging studies such as magnetic resonance imaging and dynamic tomography of myelography is necessary for diagnosis. Due to the debilitating condition, several therapeutic approaches have been developed, ranging from more conservative approaches, with observation and use of analgesics, to more invasive interventions such as surgical ligation, transvenous embolization and blood tamponade.

Tandem cranial and spinal cerebrospinal fluid leaks presenting with otogenic tension pneumocephalus: illustrative case.

Cranial and spinal cerebrospinal fluid (CSF) leaks are associated with opposite CSF fluid dynamics. The differing pathophysiology between spontaneous cranial and spinal CSF leaks are, therefore, mutually exclusive in theory. A 66-year-old female presented with tension pneumocephalus. The patient underwent computed tomography (CT) scanning, which demonstrated left-sided tension pneumocephalus, with an expanding volume of air directly above a bony defect of the tegmen tympani and mastoideum. The patient underwent a left middle fossa craniotomy for repair of the tegmen CSF leak. In the week after discharge, she developed a recurrence of positional headaches and underwent head CT. Further magnetic resonance imaging of the brain and thoracic spine showed bilateral subdural hematomas and multiple meningeal diverticula. Cranial CSF leaks are caused by intracranial hypertension and are not associated with subdural hematomas. Clinicians should maintain a high index of suspicion for intracranial hypotension due to spinal CSF leak whenever "otogenic" pneumocephalus is found. Close postoperative follow-up and clinical monitoring for symptoms of intracranial hypotension in any patients who undergo repair of a tegmen defect for otogenic pneumocephalus is recommended.

Spontaneous Intracranial Hypotension in Pregnancy.

Spontaneous intracranial hypotension (SIH) is a debilitating disease typically featuring orthostatic headache and caused by a spinal CSF leak. This review will describe the characteristics of SIH in pregnant patients and the associated unique management and treatment considerations. Herein, a novel case is reported of a 41-year-old woman who presented with SIH pre-conception but saw marked improvement of symptoms after 5weeks antepartum and symptom recurrence 2months post-partum. A literature review of SIH in pregnancy revealed 14 reported patients across 10 studies since 2000. All the reported cases resulted in delivery of healthy infants and symptomatic improvement with conservative management or a variety of treatment modalities including non-targeted epidural blood patch (EBP). Clinical and imaging features of SIH in pregnancy are reviewed. We hypothesize an antenatal protective mechanism against SIH symptoms through cephalad redistribution of CSF volume from the spinal to intracranial compartments related to uterine growth and decreased CSF volume within the lumbar cistern. Treatment recommendations are discussed including duration of bed rest and decision for non-targeted multi-site EBPs. When required, non-invasive diagnostic spine MRI using fat-suppressed axial T2-weighted imaging may be helpful.

Importance of Multimodal Spinal Cord Monitoring and Hemodynamic Augmentation during High Thoracic Ventral Dural Tear Repair Using the Posterior Approach

AbstractCerebrospinal fluid (CSF) leakage due to large ventral dural tears (VDT) often requires surgical intervention. Surgical closure of a high thoracic VDT is challenging and associated with high morbidity, especially if it is performed after multiple epidural blood patch (EBP)/fibrin glue injections. A 44-year-old woman was diagnosed with spontaneous intracranial hypotension due to VDT at T1-T2, causing CSF leakage. Multiple EBP and fibrin glue injections failed to treat her symptoms; hence, the patient underwent surgical closure using the posterior approach. The patient was anesthetized using standard anesthetic drugs and was maintained under total intravenous anesthesia to facilitate continuous motor-evoked potential (MEP) monitoring. The surgical course was complicated by bleeding, hypotension, and MEP loss. Continuous MEP monitoring, effective team communication, quick restoration of blood pressure(BP) and BP augmentation with fluid, blood, and vasopressor helped to restore the MEP back to baseline. Hence, the patient recovered without neurological morbidity. This case report highlights the importance of adequate vascular access, multimodal spinal cord monitoring, and BP augmentation during a high thoracic VDT repair.

410 Is a Single Dose, Single Agent Peri-Operative Antibiotic Protocol Adequate for Endoscopic Endonasal Skull Base Surgery? A 14-Year Review of 574 Cases

Abstract Post-operative meningitis is a rare but potentially fatal complication of endoscopic endonasal skull base surgery. As endonasal approaches to the skull base are clean-contaminated procedures, peri-operative antibiotics are routinely used. We sought to analyse the safety and efficacy of a single agent, single dose protocol in cases of endonasal anterior skull base surgery. Database of all endonasal anterior skull-base procedures performed in ENT Department at Leeds General Infirmary between 2008 and February 2022 was prospectively recorded. The primary outcome measure was development of meningitis within 30-days of surgery. Our protocol uses single dose of IV co-amoxiclav 1.2g (or teicoplanin if allergy precludes co-amoxiclav). The data was further divided according to primary or revision surgery, the presence or absence of intra-operative CSF leak, and the development or not of a post-operative CSF leak. Over the 14-year period, 574 endoscopic endonasal operations that fulfilled inclusion criteria were performed. The overall rate of post-operative meningitis across the entire cohort was 2.6%(n = 15). Among the 15 cases:80% (12/15) had intra-operative CSF leak47% (7/15) were revision cases73% (11/15) had extended endoscopic approach as pathology that required an intentional opening of the arachnoid80% (12/15) had post-operative CSF LeakThere were no cases of meningitis following repair of long-standing CSF fistula or encephalocele and surgery for sinonasal tumours with skull-base involvement. In conclusion, a single dose of 1.2g intravenous co-amoxiclav (or teicoplanin) is safe in the context of sellar-centred pathologies, repair of pre-existing spontaneous CSF leaks, and surgery on sinonasal tumours with skull base involvement.

Predictors of failure of recurrent spontaneous CSF rhinorrhea repair: a prospective cohort study

BackgroundTo identify and predict risk factors associated with recurrent spontaneous cerebrospinal fluid (CSF) rhinorrhea, a cohort study included a total of 37 adult patients with spontaneous CSF rhinorrhea were analyzed.ResultsOver a 2-year period, 37 patients of spontaneous CSF leak with exclusion of other etiologies (traumatic, congenital) were enrolled: primary (non-recurrent) (n = 20) and secondary (recurrent) (n = 17), where 83.8% were females with an average body mass index (BMI) of 36.4 kg/m2. Associated symptoms of high intracranial pressure (ICP) namely, blurred vision and unsteadiness (P-value = 0.006 and 0.01, respectively), multiparity (92.3%), and failure to localize the defect (17.6%) contributed to patients having more recurrence. Although the cribriform plate was detected frequently (n = 29.4%), they were associated with lower recurrence compared to lateral recess of sphenoid (66.6% vs 20%).ConclusionDirect endoscopic visualization and repair of skull base defects achieve a high success rate, but failure is still a possibility especially in spontaneous etiology of leaks. In a multiparous female, with high CSF pressure, lateral sphenoid recess, large size, or unidentified defect, the incidence of recurrence is much higher.Level of evidence4

Updated ultrafast dynamic computed tomography myelography technique for cerebrospinal fluid leaks.

We present an updated ultrafast dynamic computed tomography myelography technique that can be used for the localization of spontaneous spinal cerebrospinal fluid leaks in the setting of spontaneous intracranial hypotension. This has over twice the temporal resolution of previously described techniques at the same radiation dose output.

Spontaneous Intracranial Hypotension: An Uncommon Cause of Postural Vestibulocochlear Symptoms.

Spontaneous intracranial hypotension is an uncommon but increasingly recognized condition characterized by an orthostatic headache secondary to low cerebrospinal fluid pressure. Vestibulocochlear symptoms are common but rarely the only presenting feature and can be challenging to differentiate from Meniere's disease. We present a case series that highlights the common vestibulocochlear symptoms and a review of the literature to increase awareness amongst otolaryngologists and highlight the path to diagnosis and management of this condition.

Prevalence of SLEC-negative spontaneous intracranial hypotension in patients with spinal nerve root sleeve diverticula on MRI.

While there is thought to be an association between spinal nerve root diverticula (NRD) and spontaneous intracranial hypotension (SIH) without a spinal longitudinal epidural collection (SLEC), it remains unclear what the overall prevalence of SLEC-negative SIH is in patients with NRD on MRI. Spine MRI imaging reports from our single institution were electronically screened for instances of NRD over a 9-year period (2016-2023). From these cases, patients with brain MRIs consistent with SIH were also identified. Subsequently, the overall proportion of SLEC-negative SIH was determined as a function of total cases with NRD based on spinal level. In total, 83,843 patients with spinal MRIs were screened which identified 4174 (4.97%) with NRD. From these, there were 1203 cervical, 622 thoracic, and 2979 lumbosacral spine MRIs. In total, 16 patients (0.38%; Standard Error [SE]: 0.48%-0.28%) had a brain MRI compatible with SLEC-negative SIH and met ICHD-3 criteria. Patients with cervical NRD had SIH in 2 cases (0.16%; SE: 0.27%-0.05%). SLEC-negative SIH was present in 11 patients with lumbosacral NRD (0.34%; SE: 0.44%-0.24%). In patients with diverticula in the thoracic spine, 14 (2.3%; SE: 2.8%-1.8%) had SLEC-negative SIH. SLEC-negative SIH was significantly more prevalent in patients with thoracic diverticula compared to those with cervical (p<.0001) or lumbosacral NRD (p<.0001). In patients with spinal NRD, concurrent SLEC-negative SIH is present in approximately 0.38% of patients, suggesting that in the vast majority of cases, they are an incidental finding. However, SIH is present in approximately 2.3% of patients with thoracic NRD and may be more specific for leak localization.

Cervical Epidural Blood Patch for Spontaneous Intracranial Hypotension-A Case Report

Spontaneous intracranial hypotension (SIH) is an uncommon disorder caused by cerebrospinal fluid (CSF) leaks in the spine. Treatment is directed at sealing the site of leak, which is often difficult to localize. We present a case of near fatal SIH that was treated with cervical epidural blood patch (EBP) and burr hole drainage of the hematoma. A 41-year old male presented with severe headache after drinking alcohol over several weeks. Brain magnetic resonance imaging (MRI) showed features typical of SIH. But, further imaging with MR myelography and radionuclide cisternography failed to identify a precise site of leak. Despite lumbar EBP, the patient’s orthostatic headache recurred and developed acute subdural hematoma(SDH) to require burr hole drainage for hematoma evacuation. After surgery, the patient’s mental state improved, and the amount of SDH decreased, but he still complained of severe orthostatic headache. We performed EBP at cervico-thoracic junction level. The headache was rapidly relieved and the SDH was completely absorbed. In this case, we aim to remind clinicians that cervical EBP should be considered management for SIH as an alternative to the repeated lumbar blood patch.

Patient experience of spontaneous intracranial hypotension (SIH): qualitative interviews for concept elicitation

Background & objectivesSpontaneous intracranial hypotension (SIH) is an underdiagnosed and debilitating condition caused by a spinal cerebrospinal fluid (CSF) leak. Although SIH can lead to substantial morbidity and disability, little data exists about patients’ perspectives. Without hearing directly from patients, our understanding of the full experience of having SIH is limited, as is our ability to identify and use appropriate patient-reported outcome measures (PROMs) within clinical care and research. The purpose of this study was to conduct qualitative interviews with confirmed SIH patients to fully describe their experiences and identify relevant concepts to measure.MethodsPatients were recruited from an SIH specialty clinic at a large, U.S.-based healthcare center. Patients undergoing an initial consultation who were ≥ 18 years old, English-speaking, met the International Classification of Headache Disorders-3 criteria for SIH, and had a brain MRI with contrast that was positive for SIH were eligible to participate. During semi-structured qualitative interviews with a trained facilitator, participants were asked to describe their current SIH symptoms, how their experiences with SIH had changed over time, and the aspects of SIH that they found most bothersome. Analysts reviewed the data, created text summaries, and wrote analytic reports.ResultsFifteen participants completed interviews. Common symptoms reported by patients included headache, tinnitus, ear fullness/pressure/pain, and neck or interscapular pain. Patients reported that their symptoms worsened over the course of their day and with activity. The most bothersome aspect of SIH was disruption to daily activities and limits to physical activities/exercise, which were severe. With regard to symptoms, the most bothersome and impactful included physical pain and discomfort (including headache), as well as fatigue.ConclusionsPatients reported a diverse set of symptoms that were attributed to SIH, with devastating impacts on functioning and high levels of disability. Researchers considering use of PROMs for SIH should consider inclusion of both symptom scales and aspects of functioning, and future work should focus on evaluating the validity of existing measures for this patient population using rigorous qualitative and quantitative methods in diverse samples. Additionally, these data can be used to assist clinicians in understanding the impacts of SIH on patients.

Outcomes of Spontaneous Cerebrospinal Fluid Leak Repair With Concurrent Eustachian Tube Dysfunction.

To compare the presentation and outcomes of patients with and without obstructive eustachian tube dysfunction (oETD) undergoing repair of lateral skull base spontaneous cerebrospinal fluid (sCSF) leaks. Retrospective chart review. Tertiary referral center. Adults with lateral skull base sCSF leaks who underwent repairs from January 1, 2011, to December 31, 2020, were collected. Comparative statistics and effect sizes were used to compare clinical features, operative findings, and outcomes between groups. Of 92 ears from 89 patients included, 51.1% (n = 47) had oETD. There were no differences in demographics between patients with and without oETD. Mean age was 60.7 ± 13.1 versus 58.5 ± 12.8 years (d = -0.17 [-0.58 to 0.24]), mean body mass index was 33.8 ± 8.5 versus 36.0 ± 8.0 kg/m2 (d = 0.27 [-0.14 to 0.68]), and female sex preponderance was 59.6% (n = 28) versus 68.8% (n = 31; Φ = -0.09), respectively. There were no differences in the radiologic number, size, and locations of defects. Patients with oETD had less pneumatized mastoids than those without oETD (p = 0.001; Φ = 0.43). Mean change from preoperative to postoperative air pure-tone average for those with and without oETD was -1.1 ± 12.6 versus 0.1 ± 17.2 dB (d = 0.09 [-0.04 to 0.58]), respectively. Six ears (6.5%; three with and three without oETD) underwent revisions for rhinorrhea/otorrhea between 5 and 28 months postoperatively, during which four leaks were found, the two patients without leaks had oETD. The presentation of sCSF leaks and outcomes of repairs in patients with oETD do not differ from those without oETD. Although postoperative otorrhea might represent an inflammatory or infectious process in patients with oETD, reexploration is warranted if patients do not improve with conservative treatment.

Successful Cervical Epidural Blood Patch as a Treatment of Spontaneous Intracranial Hypotension - A Case Report

Background: Spontaneous intracranial hypotension can be a source of headache due to a continuous cerebrospinal fluid leakage. Case: A 33-year-old male patient with unremarkable history was presented with a headache, accompanying posterior neck stiffness and tinnitus lasting for 4 days. The opening pressure from cerebrospinal fluid tapping was 60mmH2O. Magnetic resonance imaging of the neck showed fluid collection at right C1-2 level, suggesting spontaneous intracranial hypotension. The headache did not respond to conservative treatments. Epidural blood patch was performed at C4-5 level. On postoperative day 1, remnant headache was only 20 percent and patient was discharged the day after. Conclusions: In spontaneous intracranial hypotension with leakage site at high cervical level, an epidural blood patch at a different cervical level can be safely performed to relieve the symptoms.

Validity of the Bern Score as a Surrogate Marker of Clinical Severity in Patients with Spontaneous Intracranial Hypotension.

The Bern score is a quantitative scale characterizing brain MR imaging changes in spontaneous intracranial hypotension. Higher scores are associated with more abnormalities on brain MR imaging, raising the question of whether the score can serve as a measure of disease severity. However, the relationship between clinical symptom severity and the Bern score has not been evaluated. Our purpose was to assess correlations between Bern scores and clinical headache severity in spontaneous intracranial hypotension. This study was a single-center, retrospective cohort of patients satisfying the International Classification of Headache Disorders-3 criteria for spontaneous intracranial hypotension. Fifty-seven patients who completed a pretreatment headache severity questionnaire (Headache Impact Test-6) and had pretreatment brain MR imaging evidence of spontaneous intracranial hypotension were included. Pearson correlation coefficients (ρ) for the Headache Impact Test-6 and Bern scores were calculated. Receiver operating characteristic curves were used to assess the ability of Bern scores to discriminate among categories of headache severity. We found low correlations between clinical headache severity and Bern scores (ρ = 0.139; 95% CI, -0.127-0.385). Subgroup analyses examining the timing of brain MR imaging, symptom duration, and prior epidural blood patch showed negligible-to-weak correlations in all subgroups. Receiver operating characteristic analysis found that the Bern score poorly discriminated subjects with greater headache severity from those with lower severity. Pretreatment Bern scores show a low correlation with headache severity in patients with spontaneous intracranial hypotension. This finding suggests that brain imaging findings as reflected by Bern scores may not reliably reflect clinical severity and should not replace clinical metrics for outcome assessment.

Bilateral Sensorineural Hearing Loss Related to a Skull Base Spontaneous Cerebrospinal Fluid Leak: A Case Report and Literature Review.

Spontaneous intracranial hypotension (SIH) is a rare condition characterized by orthostatic headache, pulsatile tinnitus, vertigo, nausea, and fluctuating hearing loss; this latter seems to be due to the development of cochlear endolymphatic hydrops following negative cerebrospinal fluid (CSF) pressure transmitted to the perilymphatic space through a patent cochlear aqueduct. We here describe a case of bilateral progressive sensorineural hearing loss (SNHL) due to intracranial hypotension caused by an undiagnosed spontaneous CSF leak from a skull base defect in a middle-aged woman. To the best of our knowledge, this is the first report describing a SNHL in a patient affected by SIH secondary to sphenoidal CSF leak.