Spontaneous Intracranial Hypotension

Assessing the effects of spontaneous intracranial hypotension on quality of life, work ability and disability

BACKGROUND

Spontaneous intracranial hypotension (SIH), characterized by headaches due to cerebrospinal fluid leaks or low pressure, is a challenging condition to diagnose and treat and affects the quality of life.

METHODS

An 8‑week online survey was conducted to assess the impact of SIH on symptoms, sociodemographics and quality of life. The cohort was comprised of patients who had a self-reported diagnosis of SIH and were divided into two groups: those with radiological evidence of SIH and those with clinical suspicion but no radiological evidence. Mental health and disability were evaluated using the Depression, Anxiety and Stress Scale-21 (DASS-21) and the Henry Ford Hospital Headache Disability Inventory (HDI).

RESULTS

A total of 86 participants were included in the study, 59 with radiological evidence and 27 without. Most participants were female (84.9%) with a mean age of 44.8 years. Orthostatic headache was more common in participants without radiological evidence (74.1% vs. 42.4%). The severity in those with radiological evidence was 27.1% mild, 27.1% moderate, 30.5% severe and 15.3% extremely severe, while those without had 7.4% mild, 18.5% moderate, 63.0% severe and 11.1% extremely severe headaches. Mental health assessment using the DASS-21 scale showed that 77.9% of all participants reported signs of depression, 96.5% reported anxiety and 89.5% reported stress. The HDI showed 2.3% total disability, 40.7% severe, 19.8% moderate and 37.2% mild. The impact on employment was significant: 15.1% were able to work full-time, 48.8% part-time, 30.2% were unable to work and 5.8% retired early due to SIH.

CONCLUSION

The study demonstrates the broad impact of SIH affecting physical health, mental well-being, and socioeconomic status, and calls for multifaceted and robust management approaches to address its complex effects on patients.

Spontaneous intracranial hypotension mimicking iatrogenic spinal cerebrospinal fluid leaks

OBJECTIVE

To raise awareness that patients with persistent post-dural puncture headache should be considered for evaluation of spontaneous cerebrospinal fluid (CSF) leak.

BACKGROUND

Spontaneous intracranial hypotension (SIH) due to a spinal CSF leak may occur following more-or-less trivial traumatic events. We report our experience with spontaneous spinal CSF leaks that occur following percutaneous or open spine procedures, a potential source of diagnostic confusion.

METHODS

In a retrospective cohort study, using a prospectively maintained database of patients with SIH, we identified all new patients evaluated between January 1, 2022, and June 30, 2023, who were referred for evaluation of an iatrogenic spinal CSF leak but were found to have a spontaneous spinal CSF leak.

RESULTS

Nine (4%) of the 248 patients with SIH were originally referred for evaluation of an iatrogenic spinal CSF leak. The spinal procedures included epidural steroid injections, laminectomies, epidural anesthesia, and lumbar puncture. Brain magnetic resonance imaging (MRI) showed changes in intracranial hypotension in seven of the nine patients (78%). The spontaneous CSF leak was found to be at least five levels removed from the spinal procedure in all patients.

CONCLUSIONS

A spontaneous spinal CSF leak should be suspected in patients with recalcitrant orthostatic headaches following a spinal procedure, even if symptoms of the leak occur within hours of the spinal procedure and especially if brain MRI is abnormal.

Sex differences in the clinical manifestations and treatment outcomes in a large cohort of spontaneous intracranial hypotension

OBJECTIVE

To determine sex differences in clinical profiles and treatment outcomes in patients with spontaneous intracranial hypotension.

BACKGROUND

Spontaneous intracranial hypotension is associated with considerable functional disability and potentially fatal complications, and it is uncertain whether males and females should be managed differently.

METHODS

This was a cohort study of consecutive patients with spontaneous intracranial hypotension enrolled from a medical center. Medical records and imaging findings were reviewed. The outcome of treatment responses to epidural blood patches and risks of subdural hematoma were measured.

RESULTS

In total, 442 patients with spontaneous intracranial hypotension (165 males, 277 females) were included in the analysis. Males were more likely to have a delayed (>30 days) initial presentation than females (32.1% [53/165] vs. 19.9% [55/277], p = 0.004), and males were less likely to have nausea (55.8% [92/165] vs. 67.1% [186/277], p = 0.016), vomiting (43.0% [71/165] vs. 54.2% [150/277], p = 0.024), photophobia (9.7% [16/165] vs. 17.0% [47/277], p = 0.034), and tinnitus (26.7% [44/165] vs. 39.7% [110/277], p = 0.005) compared with females despite comparable radiologic findings. Among the 374 patients treated with epidural blood patches, males were more likely to be nonresponders to the first epidural blood patch (58.0% [80/138] vs. 39.0% [92/236], OR = 2.2, 95% CI = 1.4-3.3, p < 0.001). Males were at a higher risk of having subdural hematoma (29.7% [49/165] vs. 10.8% [30/277], OR = 3.5, 95% CI = 2.1-5.8, p < 0.001). Among patients with subdural hematoma, males had greater thickness (12.8 ± 4.3 vs. 8.1 ± 5.9 mm, p < 0.001) and were more likely to receive surgical drainage (55.1% [27/49] vs. 10.0% [3/30], OR = 11.0, 95% CI = 3.0-41.3, p < 0.001) than females.

CONCLUSION

In the present study, spontaneous intracranial hypotension in males was characterized by a delayed presentation, poorer response to the first epidural blood patch, and a higher risk of subdural hematoma. Caution should be exercised in the management of males with spontaneous intracranial hypotension. The generalizability of the findings needs to be further confirmed.

Anterior Thoracic Discectomy and Fusion for Symptomatic Ventral Bone Spur Associated Type I Cerebrospinal Fluid Leak: A Technical Report and Operative Video

STUDY DESIGN

Technical Report.

OBJECTIVE

Cerebrospinal fluid (CSF) leak secondary to anterior osteophytes at the cervico-thoracic junction is a rare cause of intracranial hypotension. In this article we describe a technique for anterior repair of spontaneous ventral cerebrospinal fluid leaks in the upper thoracic spine.

METHODS

In this technical report and operative video, we describe a 23-year-old male who presented with positional headaches and bilateral subdural hematoma. Dynamic CT myelography demonstrated a high flow ventral cerebrospinal fluid leak associated with a ventral osteophyte at the level of the T1-T2 disc space. Targeted blood patch provided only temporary improvement in symptoms. An anterior approach was chosen to remove the offending spur and micro-surgically repair the dural defect.

RESULTS

The patient had complete resolution of his preoperative symptoms after primary repair.

CONCLUSIONS

In select cases, an anterior approach to the upper thoracic spine is effective to repair Type 1 cerebrospinal fluid leaks.

Patterns of clinical and imaging presentations in patients with spontaneous intracranial hypotension due to spinal cerebrospinal fluid venous fistula: A single-center retrospective cross-sectional study

OBJECTIVE

To identify distinct clinical or imaging subtypes of spontaneous intracranial hypotension (SIH) due to spinal cerebrospinal fluid (CSF) venous fistula (CVF).

BACKGROUND

Spontaneous intracranial hypotension is classically understood to present clinically with an orthostatic headache and stereotyped brain magnetic resonance imaging (MRI) findings; however, most prior literature examining clinical and brain MRI features of SIH has focused on all types of spinal CSF leaks concurrently. This study aimed to evaluate whether data support the possibility of internally consistent subtypes based on brain imaging features and clinical symptoms analogous to those seen in primary headache syndromes.

METHODS

This retrospective cross-sectional single-institution study included 48 consecutive patients meeting the International Classification of Headache Disorders, 3rd edition criteria for SIH due to CVF. Clinical symptoms, pre-treatment brain MRI, and symptom duration were analyzed. Clinical and MRI data were analyzed to identify patterns and associations between symptoms and imaging findings.

RESULTS

A total of 20 males and 28 females were evaluated, with a mean (standard deviation) age of 61 (10) years. In all, 44/48 (92%) patients experienced headaches, though 18/48 (40%) did not endorse relief when flat, including six of the 48 (13%) with worsening symptoms when flat. In all, 19/48 (40%) patients reported at least one migraine symptom, and six of the 48 (13%) presented with at least one migraine symptom and had no relief when flat. Clinical symptoms clustered primarily into a "classic" presentation consisting of relief when flat, occipital head pain, comorbid neck pain, a pressure/throbbing headache quality, and an "atypical" presentation that was characterized by having several differences: less relief when flat (nine of 22 (41%) vs. 20/23 (87.0%), p = 0.002; odds ratio [OR] 0.110, 95% confidence interval [CI] 0.016-0.53), more frontal head pain (14/22 (64%) vs. one of 23 (4%), p < 0.001; OR 35.0, 95% CI 4.2-1681.0), less neck pain (two of 21 (4.5%) vs. nine of 13 (69.6%), p < 0.001; OR 0.023, 95% CI 0.0005-0.196), and more stabbing/sharp headache quality (nine of 22 (41%) vs. two of 23 (9%), p = 0.017; OR 7.0, 95% CI 1.18-75.9). Brain MRI findings clustered into three groups: those presenting with most imaging findings of SIH concurrently, those with brain sag but less pachymeningeal/venous engorgement, and those with pachymeningeal/venous engorgement but less brain sag.

CONCLUSION

This study highlights the clinical and imaging diversity among patients with SIH due to CVF, challenging the reliance on classic orthostatic headache alone for diagnosis. The findings suggest the existence of distinct SIH subtypes based on clinical and imaging presentations, underscoring the need for comprehensive evaluation in patients with suspected CVF. Future research should further elucidate the relationship between clinical symptoms and imaging findings, aiming to refine diagnostic criteria and enhance understanding of SIH's pathophysiology.

Non-targeted serial epidural blood patches for the treatment of intracranial hypotension headache during late pregnancy: a case report

Intracranial hypotension can cause persistent and severe orthostatic headaches. It is often the result of cerebrospinal fluid leakage secondary to iatrogenic causes. It can also happen spontaneously. Diagnosing and managing severe orthostatic headaches associated with intracranial hypotension can be challenging, particularly during late pregnancy. This case describes a parturient at 30 weeks' gestation who presented with severe headaches due to intracranial hypotension caused by dural defects and cerebrospinal fluid venous fistula. She was managed with serial non-targeted epidural blood patching as a bridging remedy. This allowed further fetal maturity before delivery and definitive management of the dural leakage after delivery.

Intracranial findings in spontaneous intracranial hypotension: Does the severity of abnormalities correspond with certainty and/or multifocality of cerebrospinal fluid leaks?

BACKGROUND AND PURPOSE

Spontaneous intracranial hypotension (SIH) is caused by spinal cerebrospinal fluid (CSF) leaks. This study assessed whether the certainty and/or multifocality of CSF leaks is associated with the severity of intracranial sequelae of SIH.

MATERIALS AND METHODS

A retrospective review was completed of patients with suspected SIH that underwent digital subtraction myelogram (DSM) preceded by brain MRI. DSMs were evaluated for the presence or absence of a CSF leak, categorized both as positive/negative/indeterminate and single versus multifocal. Brain MRIs were assessed for intracranial sequelae of SIH based on two probabilistic scoring systems (Dobrocky and Mayo methods). For each system, both an absolute "numerical" score (based on tabulation of findings) and "categorized" score (classification of probability) were tabulated.

RESULTS

174 patients were included; 113 (64.9%) were female, average age 52.0 ± 14.3 years. One or more definite leaks were noted in 76 (43.7%) patients; an indeterminate leak was noted in 22 (12.6%) patients. 16 (16.3%) had multiple leaks. There was no significant difference in the severity of intracranial findings between patients with a single versus multiple leaks (p values ranged from .36 to .70 using categorized scores and 0.22-0.99 for numerical scores). Definite leaks were more likely to have both higher categorized intracranial scores (Mayo p = .0008, Dobrocky p = .006) and numerical scores (p = .0002 for Mayo and p = .006 for Dobrocky).

CONCLUSIONS

Certainty of a CSF leak on diagnostic imaging is associated with severity of intracranial sequelae of SIH, with definite leaks having significantly more intracranial findings than indeterminate leaks. Multifocal leaks do not cause greater intracranial abnormalities.

Spontaneous intracranial hypotension: Exploring the viability of non-contrast FLAIR as a substitute for contrast-enhanced T1WI in assessing pachymeningeal thickening

PURPOSE

To avoid contrast administration in spontaneous intracranial hypotension (SIH), some studies suggest accepting diffuse pachymeningeal hyperintensity (DPMH) on non-contrast fluid-attenuated inversion recovery (FLAIR) as an equivalent sign to diffuse pachymeningeal enhancement (DPME) on contrast-enhanced T1WI (T1ce), despite lacking thorough performance metrics. This study aimed to comprehensively explore its feasibility.

METHODS

In this single-center retrospective study, between April 2021 and November 2023, brain MRI examinations of 43 patients clinically diagnosed with SIH were assessed using 1.5 and 3.0 Tesla MRI scanners. Two radiologists independently assessed the presence or absence of DPMH on FLAIR and DPME on T1ce, with T1ce serving as a gold-standard for pachymeningeal thickening. The contribution of the subdural fluid collections to DPMH was investigated with quantitative measurements. Using Cohen's kappa statistics, interobserver agreement was assessed.

RESULTS

In 39 out of 43 patients (90.7%), pachymeningeal thickening was observed on T1ce. FLAIR sequence produced an accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 72.1%, 71.8%, 75.0%, 96.6%, and 21.4% respectively, for determining pachymeningeal thickening. FLAIR identified pachymeningeal thickening in 28 cases; however, among these, 21 cases (75%) revealed that the pachymeningeal hyperintense signal was influenced by subdural fluid collections. False-negative rate for FLAIR was 28.2% (11/39).

CONCLUSION

The lack of complete correlation between FLAIR and T1ce in identifying pachymeningeal thickening highlights the need for caution in removing contrast agent administration from the MRI protocol of SIH patients, as it reveals a major criterion (i.e., pachymeningeal enhancement) of Bern score.

Spontaneous intracranial hypotension in a patient without corpus callosum: A case report

RATIONALE

Spontaneous intracranial hypotension (SIH) is a well-established condition typically presenting with disabling orthostatic headache. Corpus callosum agenesis (CCA) is one of the most common human brain malformations with a wide spectrum of associated malformations, chromosomal abnormalities, and clinical syndromes.

PATIENT CONCERNS

A 53-year-old woman presented with recurrent orthostatic headache for about 1 month. The head computed tomography examination of the patient showed CCA and the initial pressure of subsequent lumbar puncture was only 5 centimeters cerebrospinal fluid. Magnetic resonance imaging examination confirmed CCA with gray matter heterotopia.

DIAGNOSIS

The final diagnose was SIH related headache with CCA.

INTERVENTION

The patient's symptom improved after oral hydration, intravenous fluids, and bed rest.

OUTCOME

Favorable outcome was observed.

LESSONS

Although this co-occurrence of SIH and CCA is probably coincidental, this finding suggests that the developmental malformations of the brain may lead to structural changes in brain tissue or disturbances in cerebrospinal fluid production and reflux, resulting in pathological changes over time.

De Novo Formation of Idiopathic Spinal Cord Herniation

We investigated whether idiopathic spinal cord herniation is a congenital or acquired condition and undertook a study to determine the risk of developing iSCH in patients with persistent ventral spinal CSF leaks. De novo formation of iSCH was established among all 6 patients with iSCH who had undergone prior spinal imaging for symptoms unrelated to iSCH. Among 51 patients with persistent ventral spinal CSF leaks, iSCH developed in 2 patients (probability increased from 0% at 5 years to 9.4% at 10 years). This study shows that iSCH is an acquired condition, and early treatment of ventral CSF leaks offers a unique opportunity to prevent neurologic disability.

Prevalence, clinical presentation, and treatment-management of cerebral venous thrombosis associated with spontaneous intracranial hypotension: A combined case-series and systematic literature review approach

BACKGROUND

Cerebral venous thrombosis (CVT) is a rare complication of spontaneous intracranial hypotension (SIH). Therefore, its correct diagnosis and the corresponding optimal treatment-management identification remains challenging.

METHODS

Over the last 10 years, 300 patients received a definite SIH diagnosis at our stroke center. Through thorough review of the database, we identified all patients with SIH-related CVT. In addition, we performed a systematic literature review including all publications on SIH-related CVT.

RESULTS

Five out of our 300 SIH patients showed CVT (F/M:2/3, mean age: 51.8 ± 15.7). Through the literature search, 72 additional cases were identified. Overall, the prevalence was 1.3% and main clinical presentations were orthostatic headache, nausea, and vomiting. The CVT was predominantly located at the superior sagittal sinus. Treatment strategies included anticoagulants (ACs) (43%), epidural blood patch (EBP) (19.4%), and combined AC + EBP (33.3%). In our cohort, all but one patient received combined EBP and AC. The mean clinical and radiological follow-up were 2 years and 1.5 years, respectively. Complete clinical recovery was reported in 96% of the cases, whereas 56% showed complete radiological CVT resolution. Among patients without radiological resolution (26.4%), 57% received AC-only, while 43% received combined AC + EBP. Of our five cases, all but one patient received combined AC + EBP.

CONCLUSION

The overall prevalence of SIH-related CVT was 1.3%. AC and combined AC + EBP were the most used treatment-management strategies. CVT resolution was more commonly achieved after the combined strategy. Overall, the rate of complete clinical recovery was 96%.

Lateral Spinal CSF Leaks in Patients with Spontaneous Intracranial Hypotension: Radiologic-Anatomic Study of Different Variants

BACKGROUND AND PURPOSE

Spinal CSF leaks cause spontaneous intracranial hypotension. Several types of leaks have been identified, and one of these types is the lateral dural tear. Performing myelography with the patient in the decubitus position allows precise characterization of these leaks. The purpose of the current study was to describe the different variants of spontaneous lateral CSF leaks.

MATERIALS AND METHODS

This retrospective cohort study included a consecutive group of patients with spontaneous intracranial hypotension and lateral CSF leaks who underwent digital subtraction myelography in the decubitus position and underwent surgery to repair the CSF leak between July 2018 and June 2023.

RESULTS

The mean age of the 53 patients (37 women and 16 men) was 35.5 years. Three different variants of lateral CSF leak could be identified. Forty-nine patients (92.5%) had a lateral dural tear associated with the nerve root sleeve. The dural tear was at the axilla of the nerve root sleeve in 36 patients (67.9%) and at the shoulder in 13 patients (24.5%). Four patients (7.5%) had a lateral dural tear at the level of the pedicle that was not associated with the nerve root sleeve. Findings on digital subtraction myelography were concordant with intraoperative findings in all patients. An extradural CSF collection was seen in all patients with a lateral dural tear associated with the nerve root sleeve but in only 2 of the 4 patients with the pedicular variant of a lateral dural tear.

CONCLUSIONS

We identified 3 variants of spontaneous lateral dural tears. Most lateral dural tears are associated with extradural CSF collections and arise from either the axilla (67.9%) or the shoulder (24.5%) of the nerve root sleeve. Lateral dural tears at the level of the pedicle (7.5%) not associated with the nerve root sleeve are uncommon and may require specialized imaging for their detection.

Spontaneous intracranial hypotension - a spinal disease

Spontaneous intracranial hypotension (SIH) remains an underdiagnosed condition despite increasing awareness due to recent scientific advances. Diagnosis can be delayed by the broad clinical presentation and imaging pitfalls. This results in a high degree of physical impairment for patients, including social and psychological sequelae as well as long-term damage in the case of delayed diagnosis and treatment.The study is based on a selective literature search on PubMed including articles from 1990 to 2023 and the authors' clinical experience from working in a CSF center.SIH mostly affects middle-aged women, with the primary symptom being position-dependent orthostatic headache. In addition, there is a broad spectrum of possible symptoms that can overlap with other clinical conditions and therefore complicate the diagnosis. The causative spinal CSF loss can be divided into three main types: ventral (type 1) or lateral (type 2) dural leak and CSF-venous fistula (type 3). The diagnosis can be made using a two-stage workup. As a first step, noninvasive MRI of the head and spine provides indicators of the presence of SIH. The second step using focused myelography can identify the exact location of the cerebrospinal fluid leak and enable targeted therapy (surgical or interventional). Intrathecal pressure measurement or intrathecal injection of gadolinium is no longer necessary for primary diagnosis. Serious complications in the course of the disease can include space-occupying subdural hematomas, superficial siderosis, and symptoms of brain sagging, which can lead to misinterpretations. Treatment consists of closing the dural leak or the cerebrospinal fluid fistula. Despite successful treatment, a relapse can occur, which highlights the importance of follow-up MRI examinations and emphasizes the chronic nature of the disease. This paper provides an overview of the diagnostic workup of patients with suspected SIH and new developments in imaging and therapy. · SIH is an underdiagnosed condition with a wide range of possible symptoms.. · The first diagnostic step using MRI provides indications of the presence of SIH.. · The second diagnostic step using (dynamic) myelography can identify the CSF leak.. · Collaboration with a CSF center is advisable for further diagnosis and treatment.. · Prompt detection and treatment of SIH improves the outcome.. · Zander C, Wolf K, El Rahal A et al. Spontaneous intracranial hypotension - a spinal disease. Fortschr Röntgenstr 2024; DOI 10.1055/a-2318-8994.

Cerebrospinal Fluid-Venous Fistulas

Cerebrospinal fluid-venous fistulas (CSFVFs) were first described in 2014 and have since become an increasingly diagnosed cause of spontaneous intracranial hypotension due to increased clinical recognition and advancements in diagnostic modalities. In this review, the authors discuss CSFVF epidemiology, the variety of clinical presentations, the authors' preferred diagnostic approach, recent advancements in diagnostic methods, treatment options, current challenges, and directions of future research.

Long-Term Epidural Patching Outcomes and Predictors of Benefit in Patients With Suspected CSF Leak Nonconforming to ICHD-3 Criteria

BACKGROUND AND OBJECTIVES

Spinal CSF leaks lead to spontaneous intracranial hypotension (SIH). While International Classification of Headache Disorders, Third Edition (ICHD-3) criteria necessitate imaging confirmation or low opening pressure (OP) for SIH diagnosis, their sensitivity may be limited. We offered epidural blood patches (EBPs) to patients with symptoms suggestive of SIH, with and without a documented low OP or confirmed leak on imaging. This study evaluates the efficacy of this strategy.

METHODS

We conducted a prospective cohort study with a nested case-control design including all patients who presented to a tertiary headache clinic with clinical symptoms of SIH who completed study measures both before and after receiving an EBP between August 2016 and November 2018.

RESULTS

The mean duration of symptoms was 8.7 ± 8.1 years. Of 85 patients assessed, 69 did not meet ICHD-3 criteria for SIH. At an average of 521 days after the initial EBP, this ICHD-3-negative subgroup experienced significant improvements in Patient-Reported Outcomes Measurement Information System (PROMIS) Global Physical Health score of +3.3 (95% CI 1.5-5.1), PROMIS Global Mental Health score of +1.8 (95% CI 0.0-3.5), Headache Impact Test (HIT)-6 head pain score of -3.8 (95% CI -5.7 to -1.8), Neck Disability Index of -4.8 (95% CI -9.0 to -0.6) and PROMIS Fatigue of -2.3 (95% CI -4.1 to -0.6). Fifty-four percent of ICHD-3-negative patients achieved clinically meaningful improvements in PROMIS Global Physical Health and 45% in HIT-6 scores. Pain relief following lying flat prior to treatment was strongly associated with sustained clinically meaningful improvement in global physical health at an average of 521 days (odds ratio 1.39, 95% CI 1.1-1.79; p < 0.003). ICHD-3-positive patients showed high rates of response and previously unreported, treatable levels of fatigue and cognitive deficits.

DISCUSSION

Patients who did not conform to the ICHD-3 criteria for SIH showed moderate rates of sustained, clinically meaningful improvements in global physical health, global mental health, neck pain, fatigue, and head pain after EBP therapy. Pre-treatment improvement in head pain when flat was associated with later, sustained improvement after EBP therapy among patients who did not meet the ICHD-3 criteria.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that epidural blood patch is an effective treatment of suspected CSF leak not conforming to ICHD-3 criteria for SIH.

Evaluation of MR Elastography as a Noninvasive Diagnostic Test for Spontaneous Intracranial Hypotension

BACKGROUND AND PURPOSE

Spontaneous intracranial hypotension is a condition resulting from a leak of CSF from the spinal canal arising independent of a medical procedure. Spontaneous intracranial hypotension can present with normal brain MR imaging findings and nonspecific symptoms, leading to the underdiagnosis in some patients and unnecessary invasive myelography in others who are found not to have the condition. Given the likelihood that spontaneous intracranial hypotension alters intracranial biomechanics, the goal of this study was to evaluate MR elastography as a potential noninvasive test to diagnose the condition.

MATERIALS AND METHODS

We performed MR elastography in 15 patients with confirmed spontaneous intracranial hypotension from September 2022 to April 2023. Age, sex, symptom duration, and brain MR imaging Bern score were collected. MR elastography data were used to compute stiffness and damping ratio maps, and voxelwise modeling was performed to detect clusters of significant differences in mechanical properties between patients with spontaneous intracranial hypotension and healthy control participants. To evaluate diagnostic accuracy, we summarized each examination by 2 spatial pattern scores (one each for stiffness and damping ratio) and evaluated group-wise discrimination by receiver operating characteristic curve analysis.

RESULTS

Patients with spontaneous intracranial hypotension exhibited significant differences in both stiffness and damping ratio (false discovery rate-corrected, Q < 0.05). Pattern analysis discriminated patients with spontaneous intracranial hypotension from healthy controls with an area under the curve of 0.97 overall, and the area under the curve was 0.97 in those without MR imaging findings of spontaneous intracranial hypotension.

CONCLUSIONS

Results from this pilot study demonstrate MR elastography as a potential imaging biomarker and a noninvasive method for diagnosing spontaneous intracranial hypotension, including patients with normal brain MR imaging findings.

Optic Nerve Sheath MR Imaging Measurements in Patients with Orthostatic Headaches and Normal Findings on Conventional Imaging Predict the Presence of an Underlying CSF-Venous Fistula

BACKGROUND AND PURPOSE

Spontaneous spinal CSF leaks typically cause orthostatic headache, but their detection may require specialized and invasive spinal imaging. We undertook a study to determine the value of simple optic nerve sheath MR imaging measurements in predicting the likelihood of finding a CSF-venous fistula, a type of leak that cannot be detected with routine spine MR imaging or CT myelography, among patients with orthostatic headache and normal conventional brain and spine imaging findings.

MATERIALS AND METHODS

This cohort study included a consecutive group of patients with orthostatic headache and normal conventional brain and spine imaging findings who underwent digital subtraction myelography under general anesthesia to look for spinal CSF-venous fistulas.

RESULTS

The study group consisted of 93 patients (71 women and 22 men; mean age, 47.5 years; range, 17-84 years). Digital subtraction myelography demonstrated a CSF-venous fistula in 15 patients. The mean age of these 8 women and 7 men was 56 years (range, 23-83 years). The mean optic nerve sheath diameter was 4.0 mm, and the mean perioptic subarachnoid space was 0.5 mm in patients with a CSF-venous fistula compared with 4.9 and 1.2 mm, respectively, in patients without a fistula (P < .001). Optimal cutoff values were found at 4.4 mm for optic nerve sheath diameter and 1.0 mm for the perioptic subarachnoid space. Fistulas were detected in about 50% of patients with optic nerve sheath diameter or perioptic subarachnoid space measurements below these cutoff values compared with <2% of patients with optic nerve sheath diameter or perioptic subarachnoid space measurements above these cutoff values. Following surgical ligation of the fistula, optic nerve sheath diameter increased from 4.0 to 5.3 mm and the perioptic subarachnoid space increased from 0.5 to 1.2 mm (P < .001).

CONCLUSIONS

Concerns about a spinal CSF leak should not be dismissed in patients with orthostatic headache when conventional imaging findings are normal, and simple optic nerve sheath MR imaging measurements can help decide if more imaging needs to be performed in this patient population.

Spontaneous Intracranial Hypotension: Clinical Presentation, Diagnosis, and Treatment Strategies

Spontaneous intracranial hypotension (SIH) typically presents as an acute orthostatic headache during an upright position, secondary to spinal cerebrospinal fluid leaks. New evidence indicates that a lumbar puncture may not be essential for diagnosing every patient with SIH. Spinal neuroimaging protocols used for diagnosing and localizing spinal cerebrospinal fluid leaks include brain/spinal MRI, computed tomography myelography, digital subtraction myelography, and radionuclide cisternography. Complications of SIH include subdural hematoma, cerebral venous thrombosis, and superficial siderosis. Treatment options encompass conservative management, epidural blood patches, and surgical interventions. The early application of epidural blood patches in all patients with SIH is suggested.

Pearls & Oy-sters: Bibrachial Amyotrophy From a Dural Tear

Bibrachial amyotrophy signifies a clinical phenotype characterized by weakness in both upper extremities with preserved strength in the face, neck, and lower extremities. The underlying causes of bibrachial amyotrophy are broad. We report a patient exhibiting bibrachial amyotrophy who initially received a diagnosis of amyotrophic lateral sclerosis (ALS); however, his clinical course and NCS/EMG were atypical for ALS. Further evaluation demonstrated dural tears with CSF leak, resulting in a compressive extradural fluid collection, ventral myelopathy, and intracranial hypotension. Dural tear and ALS have overlapping features, including the manifestation of the bibrachial amyotrophy phenotype and the presence of T2 hyperintensities in the anterior horn cells, recognized by an "owl's eye" appearance on spine MRI. Clinical and radiologic vigilance is required to identify rare cases of dural tear causing ventral myelopathy that manifest as bibrachial amyotrophy.

Impact of Spinal CSF Leaks on Quality of Life and Mental Health and Long-Term Reversal by Surgical Closure

Background and Objectives

Spontaneous intracranial hypotension (SIH) caused by a spinal CSF leak is a multisymptom syndrome, which can dramatically affect physical and mental health. However, systematic data on health-related quality of life (HRQoL) and mental health are scarce. We hypothesized that surgical treatment leads to significant and sustained improvements in HRQoL and mental health in patients with SIH.

Methods

In this single-center cohort study, we prospectively collected HRQoL and mental health data in patients undergoing surgical closure of a spinal CSF leak from September 2020 to November 2022. EuroQoL (EQ-5D-5L), including the health state index (EQ-Index) and the visual analog scale (EQ-VAS), measured HRQoL. The 21-item version of the Depression Anxiety Stress Scales (DASS-21) measured symptoms of mental health. Follow-ups were performed 3 and 6 months postoperatively. Primary outcome was the change in EQ-Index, EQ-VAS, and DASS-21 subscales. Secondary outcome was the impact of baseline depression symptoms on HRQoL outcomes following surgery.

Results

Seventy-four patients were included. EQ-VAS improved from 40 (interquartile range [IQR] 30-60) preoperatively to 70 (IQR 55-85) at 3 months and to 72 (IQR 60-88) at 6 months postoperatively (p < 0.001, respectively). EQ-Index increased from 0.683 (IQR 0.374-0.799) to 0.877 (0.740-0.943) at 3 months and to 0.907 (0.780-0.956) at 6 months postoperatively (p < 0.001, respectively). Depression, anxiety, and stress significantly improved after surgery. Preoperative depressive symptoms did not affect the HRQoL outcome.

Discussion

The severe impact of a spinal CSF leak on HRQoL and mental health significantly improved after closure of the leak. Higher levels of depressive symptoms do not predict worse outcomes and should not discourage invasive treatment. Further systematic evaluation of outcomes, with special regard to quality of life, is needed, as it allows a comparison of symptom burden between SIH and more familiar diseases as well as a comparison of different treatment modalities in future studies.

Approach to the Patient With Headache

OBJECTIVE

The evaluation of patients with headache relies heavily on the history. This article reviews key questions for diagnosing primary and secondary headache disorders with a rationale for each and phrasing to optimize the information obtained and the patient's experience.

LATEST DEVELOPMENTS

The availability of online resources for clinicians and patients continues to increase, including sites that use artificial intelligence to generate a diagnosis and report based on patient responses online. Patient-friendly headache apps include calendars that help track treatment response, identify triggers, and provide educational information.

ESSENTIAL POINTS

A structured approach to taking the history, incorporating online resources and other technologies when needed, facilitates making an accurate diagnosis and often eliminates the need for unnecessary testing. A detailed yet empathetic approach incorporating interpersonal skills enhances relationship building and trust, both of which are integral to successful treatment.

Spontaneous intracranial hypotension

Spontaneous intracranial hypotension (SIH) is a highly disabling but treatable secondary cause of headache. Recent progress in neuroradiological techniques has catalysed understanding of its pathophysiological basis and clinical diagnosis, and facilitated the development of more effective investigation and treatment methods. A UK-based specialist interest group recently produced the first multidisciplinary consensus guideline for the diagnosis and treatment of SIH. Here, we summarise a practical approach to its clinical and radiological diagnosis, symptomatic and non-targeted interventional treatment, radiological identification of leak site and targeted treatment of the leak once it has been localised.

Value of CT in targeted CT-guided epidural blood patching: Predictors for successful epidural punctures

BACKGROUND AND PURPOSE

Differentiating epidural from intrathecal punctures before computed tomography (CT)-guided epidural blood patching (EBP) is subjective, relying on operator experience. This study aimed to investigate CT findings for epidural and intrathecal punctures and identify reliable predictors for successful epidural punctures before targeted CT-guided EBP.

MATERIALS AND METHODS

We included 65 patients with low-cerebrospinal fluid (CSF)-pressure headache receiving targeted CT-guided EBP between January 2021 and October 2022 in this retrospective study. We analyzed clinical data, technical information, and CT features before EBP. Fisher's exact test was used for discrete variables, while Mann-Whitney U test was used for continuous variables. Positive (PLR) and negative likelihood ratios (NLR) were calculated to identify predictors for confirming epidural punctures.

RESULTS

We confirmed 43 patients as epidural punctures and 22 patients as intrathecal punctures. Before contrast injection, epidural fat at the needle tip in the epidural group was higher than the intrathecal group (37.2 % [16/43] vs. 4.5 % [1/22], p = 0.006). After contrast injection, the "contrast-needle tip connection" sign was mostly observed in the epidural group than the intrathecal group (95.3 % [41/43] vs. 9.1 % [2/22], p < 0.001). Additionally, the epidural group had significantly higher boomerang-shaped contrast morphology than the intrathecal group (65.1 % [28/43] vs. 9.1 % [2/22], p < 0.001). The "contrast-needle tip connection" sign had the highest PLR (10.49) and lowest NLR (0.05).

CONCLUSION

Identifying epidural fat at the needle tip, "contrast-needle tip connection" sign, and boomerang-shaped contrast morphology on CT scans are useful for confirming proper placement of the needle tip within the epidural space.

Spinal Cerebrospinal Fluid Leak Localization with Digital Subtraction Myelography: Tips, Tricks, and Pitfalls

Cerebrospinal fluid (CSF) leak can cause spontaneous intracranial hypotension (SIH) which can lead to neurologic symptoms, such as orthostatic headache. Over time, imaging techniques for detecting and localizing CSF leaks have improved. These techniques include computed tomography (CT) myelography, dynamic CT myelography, cone-beam CT, MRI, MR myelography, and digital subtraction myelography (DSM). DSM provides the highest sensitivity for identifying leak sites and has comparable radiation exposure to CT myelography. The introduction of the lateral decubitus DSM has proven invaluable in localizing leaks when other imaging tests have been inconclusive.

Diagnosis and treatment of disorders of intracranial pressure: consensus statement of the Spanish Society of Neurology's Headache Study Group

Primary intracranial pressure disorders include idiopathic intracranial hypertension and spontaneous intracranial hypotension. Remarkable advances have been made in the diagnosis and treatment of these 2entities in recent years. Therefore, the Spanish Society of Neurology's Headache Study Group (GECSEN) deemed it necessary to prepare this consensus statement, including diagnostic and therapeutic algorithms to facilitate and improve the management of these disorders in clinical practice. This document was created by a committee of experts belonging to GECSEN, and is based on a systematic review of the literature, incorporating the experience of the participants, and establishes practical recommendations with levels of evidence and grades of recommendation.

The cervical blood patch: A therapeutic "miraculous" for cerebrospinal fluid leaks: A case report

RATIONALE

Cerebrospinal fluid (CSF) leaks, arising from abnormal openings in the protective layers surrounding the spinal cord and brain, are a significant medical concern. These leaks, triggered by various factors including trauma, medical interventions, or spontaneous rupture, lead to the draining of CSF-an essential fluid safeguarding the nervous system. A classic symptom of CSF leaks is an incapacitating headache exacerbated by sitting or standing but relieved by lying down. Spontaneous intracranial hypotension (SIH) denotes the clinical condition marked by postural headaches due to spontaneous CSF leakage and hypotension, often misdiagnosed or underdiagnosed. While orthostatic headaches are the hallmark, SIH may manifest with an array of symptoms including nausea, tinnitus, hearing loss, visual disturbances, and dizziness. Treatment options encompass conservative measures, epidural blood patches (EBP), and surgery, with EBP being the primary intervention.

PATIENT CONCERN

The patient did not express any specific concerns regarding their medical diagnosis. However, they did harbor apprehensions that their condition might necessitate surgical intervention in the future.

DIAGNOSIS

The patient had been treated with antibiotics with a pre-diagnosis of sinusitis and was admitted to the neurology department of our hospital when his symptoms failed to improve. Cranial magnetic resonance imaging was interpreted as thickening of the dural surfaces and increased contrast uptake, thought to be due to intracranial hypotension. Cranial MR angiography was normal. Full-spine magnetic resonance imaging revealed a micro-spur at the C2 to 3 level and the T1 to 2 level in the posterior part of the corpus.

INTERVENTIONS

The cervical EBP was performed in the prone position under fluoroscopic guidance. There were no complications.

OUTCOMES

The patient was invited for follow-up 1 week after the procedure, and control examination was normal.

LESSONS

SIH poses a diagnostic challenge due to its diverse clinical presentation and necessitates precise imaging for effective intervention. Cervical EBP emerges as a promising treatment modality, offering relief and improved quality of life for individuals grappling with this condition. However, clinicians must carefully assess patients and discuss potential risks and benefits before opting for cervical blood patches.

Management of cervical CSF-venous fistula causing acute cognitive impairment and coma

CSF-venous fistulas (CVFs) are increasingly recognised as a cause of spontaneous intracranial hypotension. They may present atypically including with brain sagging pseudo-dementia. Cervical CVFs are rare and their management can be difficult due to associated eloquent nerve roots. We report the case of a 49-year-old woman who presented with cognitive decline progressing to coma. Brain imaging showed features of spontaneous intracranial hypotension and a right C7 CVF was identified at digital subtraction and CT myelography. Initial treatment with CT-guided injection of fibrin sealant produced temporary improvement in symptoms before surgical treatment resulted in total clinical remission and radiological resolution.

Endovascular embolization of cerebrospinal fluid-venous fistula: a comprehensive systematic review on its efficacy and safety for the management of spontaneous intracranial hypotension

Cerebrospinal fluid (CSF)-venous fistula can cause spontaneous intracranial hypotension (SIH) and poses a significant diagnostic and management challenge. This study aims to provide a comprehensive overview of the clinical and radiological outcomes of endovascular embolization as a novel treatment approach for CSF-venous fistula in patients with SIH. This systematic review adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement. The primary outcome was the efficacy of the embolization procedure in occlusion of the CSF-venous fistula, and secondary outcomes included procedural complications and improvement of clinical symptoms and radiological findings. A total of nine studies consisting of 77 patients met the inclusion criteria. Orthostatic and/or Valsalva headache was the most common symptom. The mean age of the patients was 57 ± 8.9 years, and females accounted for 59.7% (46/77) of the cases. Sixty-five (84.4%) patients reported complete resolution or significant improvement in symptoms. The Bern score, Headache Impact Test-6, and the Patient Global Impression of Change scales demonstrated significant improvements in radiological findings and patients' quality of life. Following the procedure, 22 patients (28.6%) experienced rebound intracranial hypertension and 27 patients (35.1%) had transient local pain at the site of the embolization. Our study showed that endovascular embolization is a safe and effective treatment for CSF-venous fistula in patients with SIH, providing complete resolution or significant improvement of clinical symptoms and radiological findings, and positive impacts on patients' quality of life.

Management of Labor and Anesthesia in a Patient With a History of Spontaneous Intracranial Hypotension: A Case Report With Literature Review

Spontaneous intracranial hypotension (SIH) is a rare disorder characterized by continuous or intermittent cerebrospinal fluid (CSF) leakage from the CSF cavity, which causes symptoms such as headache or neck pain upon standing. However, no well-established measures concerning the type of delivery and anesthesia for pregnant women with a history of SIH have been reported. A woman had developed SIH 9 years earlier from lifting luggage into an overhead bin with stretching movements, which required continuous saline epidural infusion for recovery. Upon the patient's pregnancy at the age of 35 years, although an elective cesarean section (CS) under general anesthesia was planned to avoid SIH recurrence, the patient had an emergency CS at 36 weeks. Since there is no prescribed method of delivery and anesthetic management for patients with a history of SIH, it is important to plan and adapt a treatment strategy based on the patient's wishes and the institution's protocols. As a sidenote, we reviewed the available literature regarding the type of delivery and anesthesia for pregnant women with a history of SIH.

Management of Tarlov cysts: an uncommon but potentially serious spinal column disease-review of the literature and experience with over 1000 referrals

Tarlov cysts were thought to be anatomic variants of uncertain etiology and clinical significance when initially described over 80 years ago. They are often detected in routine lumbosacral imaging and generally not reported in a differential diagnosis. There is increasing evidence that at least some Tarlov cysts are symptomatic and can have a significant adverse impact on patients' health and well-being. Women are disproportionately affected with this condition, often presenting with long-standing pain and neurological dysfunctions. Significant gender bias has been a concern in the management of these patients. Unfortunately, there is no consensus on patient selection or management approaches for symptomatic Tarlov cysts. This review article updates information on the prevalence, diagnosis, clinical significance, and treatments of these cysts. Based on these findings and experience with over 1000 patient referrals, a treatment decision algorithm for symptomatic Tarlov cysts was constructed to provide guidance for appropriate management of patients with these complex cysts.

Temporal Characteristics of CSF-Venous Fistulas on Dynamic Decubitus CT Myelography: A Retrospective Multi-Institution Cohort Study

BACKGROUND AND PURPOSE

CSF-venous fistula can be diagnosed with dynamic decubitus CT myelography. This study aimed to analyze the temporal characteristics of CSF-venous fistula visualization on multiphase decubitus CT myelography.

MATERIALS AND METHODS

A retrospective, multisite study was conducted on patients diagnosed with CSF-venous fistula at 2 institutions between June 2017 and February 2023. Both institutions perform decubitus CT myelography with imaging immediately following injection and usually with at least 1 delayed scan. The conspicuity of CSF-venous fistula was assessed on each phase of imaging.

RESULTS

Forty-eight patients with CSF-venous fistula were analyzed. CSF-venous fistulas were better visualized on the early pass in 25/48 cases (52.1%), the delayed pass in 6/48 cases (12.5%) and were seen equally on both passes in 15/48 cases (31.3%). Of 25 cases in which the CSF-venous fistula was better visualized on the early pass, 21/25 (84%) fistulas were still at least partially visible on a delayed pass. Of 6 cases in which the CSF-venous fistula was better visualized on a delayed pass, 4/6 (67%) were partially visible on the earlier pass. Six of 48 (12.5%) CSF-venous fistulas were visible only on a single pass. Of these, 4/6 (66.7%) were seen only on the first pass, and 2/6 (33.3%) were seen only on a delayed pass. One fistula was found with one pass only, and one fistula was discovered upon contralateral decubitus imaging without a dedicated second injection.

CONCLUSIONS

A dynamic decubitus CT myelography imaging protocol that includes an early and delayed phase, likely increases the sensitivity for CSF-venous fistula detection. Further studies are needed to ascertain the optimal timing and technique for CSF-venous fistula visualization on dynamic decubitus CT myelography and its impact on patient outcomes.

Fluctuating hearing loss secondary to spontaneous intracranial hypotension: A case report and review of the literature

OBJECTIVE

Fluctuating sensorineural hearing loss (SNHL) has multiple etiologies, most commonly Ménière's disease (MD), recurrent sudden SNHL, and autoimmune inner ear disorders. Fluctuating SNHL has rarely been described as a symptom of spontaneous intracranial hypotension (SIH).

PATIENT

A 39-year-old previously healthy female presented with "Ménière's like" symptoms responsive to steroid treatment, which worsened during the day and improved in the supine position. Conservative treatment for MD consisting of low salt and caffeine diet and betahistine medication yielded no improvement. Secondary revision of brain imaging scans showed signs indicative of SIH, and a spinal cerebrospinal fluid leak was ultimately found and treated by a novel technique of transvenous fistula embolization by means of Onyx® glue, leading to gradual clinical improvement and near-complete resolution of symptoms.

CONCLUSION

SIH should be considered as part of the differential diagnosis of fluctuating SNHL. Clinical and radiological features should be known and sought. We suspect that early diagnosis and treatment can lead to cure and prevent permanent auditory damage.

Quality of Life in Patients With Confirmed and Suspected Spinal CSF Leaks

BACKGROUND AND OBJECTIVES

Spontaneous intracranial hypotension (SIH) is a debilitating condition typically producing orthostatic headache limiting upright time. SIH is often difficult to diagnose and treat, negatively affecting quality of life (QoL) in patients with the disorder. We studied QoL in patients with confirmed and suspected SIH using standardized instruments, including suicidality.

METHODS

We performed a cross-sectional survey of adult patients with confirmed and clinically suspected SIH evaluated in our Headache and Facial Pain Program from 2016 to 2022. Using an online data collection tool (REDCap V 11.2.2), participants completed validated questionnaires assessing general well-being (SF-36), depression (PHQ-9), generalized anxiety disorder-7 (GAD-7), spiritual well-being during chronic illness therapy (FACIT-Sp-12), and headache impact (HIT-6). Subsequently, we interviewed willing participants to administer the Columbia-Suicide Severity Rating Scale (C-SSRS) assessing suicidal behavior and ideation.

RESULTS

A total of 234 patients met inclusion criteria and were invited to participate in the study, and 95 patients (59 confirmed and 36 clinically suspected) completed the questionnaires. The average age of the cohort was 51.1 years (SD: 15.5), predominantly female (69.5%), White (91.6%), and married (69.5%). Three-quarters (74.5%) scored within the most severe headache category (HIT-6). SF-36 scores were significantly inferior (p < 0.0001) to the general population and lower than reported values for patients with multiple sclerosis and idiopathic intracranial hypertension. Almost half (49.1%) of respondents scored in the moderate depression range or worse (>10), and 25.4% scored with moderate anxiety or worse (>10). FACIT-Sp-12 scores were significantly worse (p < 0.0001) in symptomatic participants than in the validation cohorts of patients with AIDS and cancer. Of the 67 respondents who completed the C-SSRS, more than half (64.2%) endorsed a wish to be dead, and 22.4% had demonstrated suicidal behavior. Patients with symptom-free SIH (n = 22) scored significantly better than symptomatic patients, comparable with the general population.

DISCUSSION

Based on our single-center cohort, SIH is associated with severe headache pain and high rates of depression, anxiety, and disability, affecting basic activities of daily living. Individuals with confirmed and suspected spinal CSF leaks scored similarly on these measures including suicidality. Outcomes were comparable with the general population after successful treatment or spontaneous remission. Improved identification and treatment of SIH are imperative to improve patients' QoL.

Sacral Dural Tears as a Cause of Spontaneous Intracranial Hypotension

PURPOSE

Dural tears at the level of the cervical, thoracic, and lumbar spine cause spontaneous intracranial hypotension (SIH) in patients with a spinal longitudinal extradural CSF collection (SLEC); however, sacral dural tears have rarely been reported so far. This study focuses on sacral dural tears as a cause of SIH.

METHODS

Retrospective data from SIH patients with confirmed sacral dural tears studied between October 2020 and November 2022 were analyzed with respect to demographic, clinical and imaging features. Digital subtraction myelography (DSM) and lumbar epidural blood patch (EBP) were modified by placing the patient in reversed Trendelenburg position.

RESULTS

Of the SIH patients, 9 (all women; mean age, 38.5 years; mean body mass index, BMI, 22.9) out of 149 had a sacral dural leak (6%) that occurred spontaneously in 7/9, while 2/9 were likely associated with minor trauma. None had a sacral fracture. The mean SIH score was 6.8. All patients showed SLEC on heavily T2-weighted MR myelography (T2-MRM), 4/9 exclusively sacral and 5/9 with partial or complete involvement of the remaining spine. 4/9 had none, but 5/9 had meningeal sacral cysts, 2/5 had large cysts/ectasia. Confirmation of the sacral origin of the leak was provided in 4/9 by T2-MRM, in 2/9 by DSM and 3/9 by CT myelography (CTM) whereas 0/9 revealed the exact site of leak within the sacrum.

CONCLUSION

Sacral dural tears should be considered as a possible cause for SIH. It is concluded to implement T2-MRM covering the entire sacrum in the standard MRI protocol and propose EBP in the reverse Trendelenburg position as a therapeutic approach.

Spontaneous Intracranial Hypotension in Pregnancy

PURPOSE OF REVIEW

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.

RECENT FINDINGS

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 5 weeks antepartum and symptom recurrence 2 months 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.

Multidisciplinary consensus guideline for the diagnosis and management of spontaneous intracranial hypotension

BACKGROUND

We aimed to create a multidisciplinary consensus clinical guideline for best practice in the diagnosis, investigation and management of spontaneous intracranial hypotension (SIH) due to cerebrospinal fluid leak based on current evidence and consensus from a multidisciplinary specialist interest group (SIG).

METHODS

A 29-member SIG was established, with members from neurology, neuroradiology, anaesthetics, neurosurgery and patient representatives. The scope and purpose of the guideline were agreed by the SIG by consensus. The SIG then developed guideline statements for a series of question topics using a modified Delphi process. This process was supported by a systematic literature review, surveys of patients and healthcare professionals and review by several international experts on SIH.

RESULTS

SIH and its differential diagnoses should be considered in any patient presenting with orthostatic headache. First-line imaging should be MRI of the brain with contrast and the whole spine. First-line treatment is non-targeted epidural blood patch (EBP), which should be performed as early as possible. We provide criteria for performing myelography depending on the spine MRI result and response to EBP, and we outline principles of treatments. Recommendations for conservative management, symptomatic treatment of headache and management of complications of SIH are also provided.

CONCLUSIONS

This multidisciplinary consensus clinical guideline has the potential to increase awareness of SIH among healthcare professionals, produce greater consistency in care, improve diagnostic accuracy, promote effective investigations and treatments and reduce disability attributable to SIH.

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

BACKGROUND AND PURPOSE

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.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Recovery and long-term outcome after neurosurgical closure of spinal CSF leaks in patients with spontaneous intracranial hypotension

INTRODUCTION

Spontaneous intracranial hypotension due to a spinal cerebrospinal fluid leak causes orthostatic headaches and impacts quality of life. Successful closure rates are often reported, whereas data on long-term outcome are still scarce.

METHODS

Between April 2020 and December 2022 surgically treated patients completed the Headache Impact Test-6 prior to surgery and at 14 days, three months, six months, and 12 months postoperatively. In addition to the Headache Impact Test-6 score, we extracted data related to orthostatic symptoms.

RESULTS

Eighty patients were included. Median Headache Impact Test-6 score preoperatively was 65 (IQR 61-69), indicating severe and disabling impact of headaches. At three months headache impact significantly improved to 49 (IQR 44-58) (p < 0.001) and remained stable up to 12 months (48, IQR 40-56), indicating little to no impact of headaches on quality of life. The need to lie down "always" or "very often" was reduced from 79% to 23% three months postoperatively (p < 0.001).

CONCLUSIONS

Surgical closure of spinal CSF leaks significantly improves the impact of headaches in the long term. At least three months should be expected for recovery. Despite permanent closure of the CSF-leak, a quarter of patients still have relevant long-term impairment, indicating the need for further research on its cause and possible treatment.

Dural and Leptomeningeal Diseases: Anatomy, Causes, and Neuroimaging Findings

Meningeal lesions can be caused by various conditions and pose diagnostic challenges. The authors review the anatomy of the meninges in the brain and spinal cord to provide a better understanding of the localization and extension of these diseases and summarize the clinical and imaging features of various conditions that cause dural and/or leptomeningeal enhancing lesions. These conditions include infectious meningitis (bacterial, tuberculous, viral, and fungal), autoimmune diseases (vasculitis, connective tissue diseases, autoimmune meningoencephalitis, Vogt-Koyanagi-Harada disease, neuro-Behçet syndrome, Susac syndrome, and sarcoidosis), primary and secondary tumors (meningioma, diffuse leptomeningeal glioneuronal tumor, melanocytic tumors, and lymphoma), tumorlike diseases (histiocytosis and immunoglobulin G4-related diseases), medication-induced diseases (immune-related adverse effects and posterior reversible encephalopathy syndrome), and other conditions (spontaneous intracranial hypotension, amyloidosis, and moyamoya disease). Although meningeal lesions may manifest with nonspecific imaging findings, correct diagnosis is important because the treatment strategy varies among these diseases. ©RSNA, 2023 Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. Quiz questions for this article are available through the Online Learning Center.

Caffeine for Headaches: Helpful or Harmful? A Brief Review of the Literature

Consumption of caffeine in the diet, both daily and occasional, has a significant biological effect on the nervous system. Caffeine, through various and not yet fully investigated mechanisms, affects headaches. This is especially noticeable in migraine. In other headaches such as hypnic headache, post-dural puncture headache and spontaneous intracranial hypotension, caffeine is an important therapeutic agent. In turn, abrupt discontinuation of chronically used caffeine can cause caffeine-withdrawal headache. Caffeine can both relieve and trigger headaches.

Rare cause of cerebral venous sinus thrombosis: Spontaneous intracranial hypotension syndrome: A case report

BACKGROUND

Spontaneous intracranial hypotension syndrome is a relatively uncommon neurological disorder of unknown etiology with a good prognosis. Cerebral venous sinus thrombosis is a specific type of cerebrovascular disease caused by multiple etiologies of cerebral venous sinus or vein thrombosis that obstructs cerebral venous return and is associated with impaired cerebrospinal fluid absorption; this entity is rarely seen clinically. Spontaneous intracranial hypotension syndrome is one of the causes of cerebral venous sinus thrombosis, and the probability of their combined occurrence is only 1%-2%. As such, it is easily overlooked clinically, thus increasing the difficulty of diagnosis and treatment.

CASE SUMMARY

A 29-year-old young woman presented with postural headache. Lumbar puncture suggested a pressure of 50 mmH₂O (normal 80 mmH₂O-180 mmH₂O), and magnetic resonance imaging cerebral venography suggested thrombosis of the supratentorial sinus. These findings were considered indicative of cerebral venous sinus thrombosis due to spontaneous intracranial hypotension syndrome after ruling out immunological causes, tumor, infection, abnormal coagulation mechanism, and hypercoagulable state, etc. She was treated with rehydration and low-molecular heparin anticoagulation for 15 d, and follow-up magnetic resonance imaging cerebral venography suggested resolution of the thrombus. The patient had complete improvement of her headache symptoms.

CONCLUSION

Spontaneous intracranial hypotension syndrome is one of the rare causes of cerebral venous sinus thrombosis, which is frequently misdiagnosed or missed and deserves consideration by clinicians during differential diagnosis. Dehydration should be avoided in such patients, and early rehydration and anticoagulation therapy are effective treatment options.

Comparing two techniques of performing an epidural catheter-assisted epidural blood patch using a 20 ml syringe versus a 5 ml syringe and its effect on clotting time, the strength of clot retraction and haemolysis - A prospective in vitro study (EC-EBP study)

Background and Aims

Epidural blood patch (EBP) is performed by injecting autologous blood into the epidural space using a Tuohy needle. Certain clinical scenarios mandate an epidural catheter (EC)-assisted EBP. Collecting blood in a 20-ml versus 5-ml syringe appears to influence the quality of the clot. This in vitro study compared the techniques of performing the EC-assisted EBP using 20-ml versus 5-ml syringe on clotting time (CT), clot retraction (CR) and haemolysis.

Methods

This in vitro study was performed in a haematology laboratory. Five consented adult healthy male volunteers donated blood. In the 5-ml syringe technique, blood was injected through an EC, and as it flowed out of the tip, it was collected at the beginning and the end of 1 min. With the 20-ml technique, blood was collected at the beginning and end of the first, second and third minute. The samples were tested for CT, CR and haemolysis by measuring the plasma-free haemoglobin (PFHb).

Results

Five injections were made using a 5-ml syringe, and another five with a 20-ml syringe. Injection time was shorter in the 5-ml technique (80.80 ± 5.89 vs. 272 ± 28.4 s, P < 0.0001). With the 20-ml technique, CT progressively increased (>15 min), whereas, with the 5-ml syringe, the CT was normal. Both techniques caused mild, insignificant haemolysis (PFHb >0.005 g/dl), without affecting the quality of CR.

Conclusion

EC-assisted EBP using a 5-ml syringe technique shortens the injection time and deposits fresh blood quickly without affecting CT and CR.

Overview of Spontaneous Intracranial Hypotension and Differential Diagnosis with Chiari I Malformation

Spontaneous intracranial hypotension (SIH) occurs due to a leakage of the cerebrospinal fluid (CSF) lowering the pressure of subarachnoid space, mostly caused by a dural breach or discogenic microspur. As a result of less support provided by CSF pressure, intracranial structures are stretched downward, leading to a constellation of more or less typical MRI findings, including venous congestion, subdural effusions, brainstem sagging and low-lying cerebellar tonsils. Clinic examination and an MRI are usually enough to allow for the diagnosis; however, finding the location of the dural tear is challenging. SIH shares some MRI features with Chiari malformation type I (CM1), especially low-lying cerebellar tonsils. Since SIH is likely underdiagnosed, these findings could be interpreted as signs of CM1, leading to a misdiagnosis and an incorrect treatment pathway. Medical treatment, including steroids, bed rest, hydration caffeine, and a blind epidural blood patch, have been used in this condition with variable success rates. For some years, CSF venous fistulas have been described as the cause of SIH, and a specific diagnostic and therapeutic pathway have been proposed. The current literature on SIH with a focus on diagnosis, treatment, and differential diagnosis with CM1, is reviewed and discussed.

[Guidelines for the Diagnosis and Treatment of Spontaneous Intracranial Hypotension]

Spontaneous intracranial hypotension (SIH) is a syndrome characterized by disabling orthostatic headache, due to reduced cerebrospinal fluid (CSF) volume probably caused by a CSF fistula. It affects mostly women of working-age, although it is probably underdiagnosed. The aim of this article is to present a practical approach to the diagnosis and treatment of SIH. After a description of its symptoms and signs, we present a step-by-step approach to the confirmation of the diagnosis and treatment, considering different clinical scenarios. This is intended to guide clinical decision making, through a systematized and individualized management, aimed at the best interest of the patient.

Super resolution imaging reconstruction reveals that gold standard methods may not correctly conclude neural/brain functional recovery

The status of cerebral perfusion and its restoration level play a vital role in the prognosis and clinical decision making of many neurosurgical diseases. As such, gold standard methods including CT, MR and ICP monitoring, which can indicate and measure cerebral perfusion and restoration, have been widely adopted to evaluate whether or not a patient has recovered from neurofunctional disabilities. This robust combination of methods, however, is confronted with a growing number of contradictions in recent years due to its inability to measure the status of cerebral reperfusion in microvasculature level, even though this has been shown to determine neurofunctional restoration as well or even better. To this date, nevertheless, we have very limited imaging methods that could evaluate human cerebral microperfusion both safely and accurately under most neurosurgical conditions. We herein report a new method of acquiring a patient's cerebral microperfusion status noninvasively which could display the precise distribution of microvasculature in deep cerebral regions with a resolution of ∼30 µm, using everyday bed-side ultrasonography combined with a computerized super-resolution reconstruction algorithm. Using this imaging modality, we found that a patient's cerebral microperfusion might not be improved by some routine administrations even though the gold standard method had yielded the opposite conclusions. Our imaging modality retains the safe, portable feature of ordinary ultrasonography while possesses the extraordinary super-resolution nature, which enables an efficient, precise diagnosis of cerebral perfusion. Most importantly, the super resolution nature of this method may also facilitate early-stage evaluation of a patient's neurofunctional restoration level and avoid overoptimistic conclusions from conventional angiography or ICP monitoring.

Diagnosis and treatment evaluation in patients with spontaneous intracranial hypotension

Spontaneous intracranial hypotension is characterized by an orthostatic headache and audiovestibular symptoms alongside a myriad of other non-specific symptoms. It is caused by an unregulated loss of cerebrospinal fluid at the spinal level. Indirect features of CSF leaks are seen on brain imaging as signs of intracranial hypotension and/or CSF hypovolaemia as well as a low opening pressure on lumbar puncture. Direct evidence of CSF leaks can frequently, but not invariably, be observed on spinal imaging. The condition is frequently misdiagnosed due to its vague symptoms and a lack of awareness of the condition amongst the non-neurological specialities. There is also a distinct lack of consensus on which of the many investigative and treatment options available to use when managing suspected CSF leaks. The aim of this article is to review the current literature on spontaneous intracranial hypotension and its clinical presentation, preferred investigation modalities, and most efficacious treatment options. By doing so, we hope to provide a framework on how to approach a patient with suspected spontaneous intracranial hypotension and help minimize diagnostic and treatment delays in order to improve clinical outcomes.