Rebound intracranial hypertension: a complication of epidural blood patching for intracranial hypotension

ACR Appropriateness Criteria® Imaging of Suspected Intracranial Hypotension

The clinical syndrome of intracranial hypotension refers to the symptoms caused by cerebrospinal fluid hypovolemia and is primarily characterized by postural headaches, but can be associated with a multitude of other neurological symptoms. Imaging plays a critical role in helping to establish a diagnosis of intracranial hypotension, localize the source of cerebrospinal fluid leak, and assist in directing targeted treatments. Using the best available evidence, this document provides diagnostic imaging recommendations for the workup of intracranial hypotension across various clinical presentations. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Perspectives from the Inaugural "Spinal CSF Leak: Bridging the Gap" Conference: A Convergence of Clinical and Patient Expertise

BACKGROUND AND PURPOSE

The inaugural "Spinal CSF Leak: Bridging the Gap" Conference was organized to address the complexities of diagnosing and treating spinal CSF leaks. This event aimed to converge the perspectives of clinicians, researchers, and patients with a patient-centered focus to explore the intricacies of spinal CSF leaks across 3 main domains: diagnosis, treatment, and aftercare.

MATERIALS AND METHODS

Physician and patient speakers were invited to discuss the varied clinical presentations and diagnostic challenges of spinal CSF leaks, which often lead to misdiagnosis or delayed treatment. Patient narratives were interwoven with discussions on advanced radiologic techniques and clinical assessments. Treatment-focused sessions highlighted patient experiences with various therapeutic options, including epidural blood patches, surgical interventions, and percutaneous and endovascular therapies. The intricacies of immediate and long-term postprocedural management were explored.

RESULTS

Key outcomes from the conference included the recognition of the need for increased access to specialized CSF leak care for patients and heightened awareness among health care providers, especially for atypical symptoms and presentations. Discussions underscored the variability in individual treatment responses and the necessity for personalized diagnostic and treatment algorithms. Postprocedural challenges such as managing incomplete symptom relief and rebound intracranial hypertension were also addressed, emphasizing the need for effective patient monitoring and follow-up care infrastructures.

CONCLUSIONS

The conference highlighted the need for adaptable diagnostic protocols, collaborative multidisciplinary care, and enhanced patient support. These elements are vital for improving the recognition, diagnosis, and management of spinal CSF leaks, thereby optimizing patient outcomes and quality of life. The event established a foundation for future advancements in spinal CSF leak management, advocating for a patient-centered model that harmonizes procedural expertise with an in-depth understanding of patient experiences.

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 Leaks: Challenges in Localizing Spontaneous Spinal Leak Sites and Minimally Invasive Treatment

The confirmation of cerebrospinal fluid (CSF) leaks in the setting of spontaneous intracranial hypotension (SIH) by imaging involves a growing toolset of multimodal advanced spinal and skull base imaging techniques, for which exists a unique set of challenges for each CSF leak type. Furthermore, the repertoire of minimally invasive CSF leak treatment beyond nontargeted epidural blood patch administration has grown widely, with varied practices across institutions. This review describes current diagnostic imaging and treatment modalities as they apply to the challenges of CSF leak localization and management.

Diagnosis and Treatment of Spontaneous Intracranial Hypotension: Role of Epidural Blood Patching

Purpose of Review

This review focuses on the challenges of diagnosing and treating spontaneous intracranial hypotension (SIH), a condition caused by spinal CSF leakage. It emphasizes the need for increased awareness and advocates for early and thoughtful use of empirical epidural blood patches (EBPs) in suspected cases.

Recent Findings

SIH diagnosis is hindered by variable symptoms and inconsistent imaging results, including normal brain MRI and unreliable spinal opening pressures. It is crucial to consider SIH in differential diagnoses, especially in patients with connective tissue disorders. Early EBP intervention is shown to improve outcomes.

Summary

SIH remains underdiagnosed and undertreated, requiring heightened awareness and understanding. This review promotes proactive EBP use in managing suspected SIH and calls for continued research to advance diagnostic and treatment methods, emphasizing the need for innovative imaging techniques for accurate diagnosis and timely intervention.

CSF-venous leak responsible for spontaneous intracranial hypotension treated by endovascular venous route: First cases in Italy

Spontaneous intracranial hypotension (SIH) is due to a leakage of CSF lowering the pressure of subarachnoid space, mostly caused by a dural breach or discogenic microspur. Clinical and MRI are usually typical enough to allow diagnosis, while finding the location of the dural breach is challenging. Since some years, CSF venous fistulas have been described as the cause of SIH, and a specific diagnostic and therapeutic path has been proposed. Here we report the first two successfully treated patients in Italy. Both had chronic and non specific symptoms, with severe reduction of quality of life; clinical symptoms improved after endovascular occlusion of the responsible vein.

Rebound Intracranial Hypertension

PURPOSE OF REVIEW

Rebound intracranial hypertension (RIH) is a post-procedural treatment complication in patients with spontaneous intracranial hypotension (SIH) characterized by transient high-pressure headache symptoms. This article reviews the epidemiology, clinical features, risk factors, and treatment options for RIH.

RECENT FINDINGS

This article discusses how changes in underlying venous pressure and craniospinal elastance can explain symptoms of RIH, idiopathic intracranial hypertension (IIH), and SIH. The pathophysiology of RIH provides a clue for how high and low intracranial pressure disorders, such as IIH and SIH, are connected on a shared spectrum.

Safety and efficacy of transvenous embolization of cerebrospinal fluid-venous fistula in patients with spontaneous intracranial hypotension

BACKGROUND

Transvenous embolization is a recent treatment strategy for cerebrospinal fluid-venous fistulas (CSFVF), which are associated with spontaneous intracranial hypotension (SIH).

METHODS

Participants were selected from a prospective database on patients with CSFVF that received transvenous Onyx embolization. All patients underwent a brain magnetic resonance imaging (MRI) before and after embolization with MRI follow-up performed at least 3 months after treatment. Clinical and MRI results after treatment were described.

RESULTS

Twenty-one consecutive patients (median age 63 years, IQR = 58-71; females: 15/21 = 71.5%) with 30 CSFVF were included. Most lesions were situated between T9 and L1 (19/30 = 63%), 70% were right-sided, and 38% of the patients had multiples fistulas. Embolization was successful in all cases. The mean MRI SIH score before and after treatment was 6 (±2.5) and 1.4 (±1.6), respectively (p < 0.0001). Twenty patients (90%) experienced improvement of their initial condition, of which 67% reported complete clinical recovery. The mean HIT-6 score decreased from 67 (±15) to 38 (±9) (p < 0.0001), the mean amount of monthly headache days from 23.5 (±10) and 3.2 (±6.6) (p < 0.0001), the visual assessment scale (VAS) for headache severity from 8 (±1.9) to 1.2 (±2) (p < 0.0001), and the mean VAS for perception quality of life improved from 2.6 (±2.5) to 8.6 (±1.8) (p < 0.0001). There were no major complications. The suspected rebound headache rate after treatment was 33%.

CONCLUSION

Transvenous embolization of CSFVF allowed high rates of clinical improvement with no morbidity related to the treatment.

Management of post blood patch severe rebound intracranial hypertension by the usage of an external ventricular drain

Spontaneous intracranial hypotension (SIH) is a condition characterised by postural headaches due to low cerebrospinal fluid (CSF) pressure, often stemming from CSF leakage. Diagnosis poses a significant challenge, and the therapeutic approach encompasses both conservative measures and operative interventions, such as the epidural blood patch (EBP). However, EBP carries the potential risk of inducing rebound intracranial hypertension (RIH), subsequently leading to high-pressure headaches. We present a case wherein RIH following EBP was effectively managed through the implementation of an external ventricular drain (EVD) aimed at reducing CSF pressure. The patient improved significantly, underscoring the potential utility, if not necessity, of EVD in carefully selected cases, highlighting the imperative for further research to enhance the management of SIH and optimise EBP-related complications.

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

BACKGROUND

The 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.

METHODS

A 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.

RESULTS

Among 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.

CONCLUSIONS

This procedure seems to be insufficient to exclude differential diagnosis when intracranial hypotension is suspected.

Percutaneous Treatment and Post-treatment Management of CSF Leaks and CSF-Venous Fistulas in Spontaneous Intracranial Hypotension

Spontaneous intracranial hypotension (SIH) is a treatable cause of orthostatic headaches secondary to pathologic loss of cerebrospinal fluid (CSF) from the subarachnoid space. SIH has several known pathologic causes including dural tears from disc osteophytes, leaks emanating from nerve root sleeve diverticula, and CSF-venous fistulas (CVFs). Depending on the type of leak, surgical repair or endovascular techniques may be options for definite treatment. However, epidural blood patching (EBP) remains first-line therapy for many patients due to its long track record, broad availability, and relatively lower risk profile. This review focuses on indications and techniques for the percutaneous treatment of SIH and provides an overview of post-procedural management of these patients.

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.

Transvenous embolization of cerebrospinal fluid-venous fistulas: Independent validation and feasibility of upper-extremity approach and using dual-microcatheter and balloon pressure cooker technique

BACKGROUND

Transvenous embolization is emerging as a promising treatment for cerebrospinal fluid-venous fistulas (CVF) associated with spontaneous intracranial hypotension (SIH).

OBJECTIVE

To perform an independent validation of the efficacy and safety of the procedure and describe the procedural techniques used at our institution.

METHODS

A retrospective review was performed including consecutive patients with SIH who had undergone CVF embolization with 3-month clinical and imaging follow-up. Clinical evaluation included the Patient Global Impression of Change (PGIC) Scale and six-item Headache Impact Test (HIT-6). Bern SIH score was used for imaging evaluation on brain MRI. Post-treatment changes in scores were assessed by Wilcoxon signed rank test. Procedural technical details, including use of upper-extremity access and dual-microcatheter pressure cooker technique, were recorded.

RESULTS

18 patients (13 female, median age 60 years) were included. 17 (94%) procedures were performed with upper-extremity access and 12 (67%) using dual-microcatheter pressure cooker technique. After embolization, 16 (89%) patients reported much or very much improved at follow-up PGIC; median (IQR) HIT-6 score improved from 68 (62-72) to 36 (36-38) and Bern SIH score improved from 8 (6-8) to 3 (1.5-3.5), p values <0.001. Side effects were transient embolization site back pain in 15 (83%) and rebound intracranial hypertension requiring medical management in 9 (50%) patients. HIT-6 and Bern SIH score changes were similar between conventional and pressure cooker techniques (p values >0.05).

CONCLUSION

Transvenous embolization is independently validated as a highly effective and safe treatment for CVF and is feasible using upper-extremity venous access. Dual-microcatheter and balloon/coil pressure cooker techniques may be used to optimize distribution of embolic material and potentially, treatment efficacy.

Brain Sagging Dementia

PURPOSE OF REVIEW

Brain sagging dementia (BSD) is a rare but devastating form of early-onset dementia characterized by intracranial hypotension and behavioral changes resembling behavioral variant frontotemporal dementia. This review aims to provide a comprehensive overview of BSD, highlighting its pathomechanism, diagnostic tools, and available treatment options.

RECENT FINDINGS

BSD exhibits a complex clinical manifestation with insidious onset and gradual progression of behavioral disinhibition, apathy, inertia, and speech alterations. Additionally, patients may exhibit brainstem and cerebellar signs such as hypersomnolence and gait disturbance. Although headaches are common, they may not always demonstrate typical orthostatic features. Recent radiological advances have improved the detection of CSF leaks, enabling targeted treatment and favorable outcomes. Understanding the pathomechanism and available diagnostic tools for BSD is crucial for a systematic approach to timely diagnosis and treatment of this reversible form of early-onset dementia, as patients often endure a complex and lengthy clinical course.

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.

Image-Guided Spine Interventions for Pain: Ongoing Controversies

An expanding array of image-guided spine interventions have the potential to provide immediate and effective pain relief. Innovations in spine intervention have proceeded rapidly, with clinical adoption of new techniques at times occurring before the development of bodies of evidence to establish efficacy. Although new spine interventions have been evaluated by clinical trials, acceptance of results has been hindered by controversies regarding trial methodology. This article explores controversial aspects of four categories of image-guided interventions for painful conditions: spine interventions for postdural puncture headache resulting from prior lumbar procedures, epidural steroid injections for cervical and lumbar radiculopathy, interventions for facet and sacroiliac joint pain, and vertebral augmentations for compression fractures. For each intervention, we summarize the available literature, with an emphasis on persistent controversies, and discuss how current areas of disagreement and challenge may shape future research and innovation. Despite the ongoing areas of debate regarding various aspects of these procedures, effective treatments continue to emerge and show promise for aiding relief of a range of debilitating conditions.

Algorithmic Multimodality Approach to Diagnosis and Treatment of Spinal CSF Leak and Venous Fistula in Patients With Spontaneous Intracranial Hypotension

Spontaneous intracranial hypotension (SIH) is a disorder of CSF dynamics that causes a complex clinical syndrome and severe disability. SIH is challenging to diagnose because of the variability of its presenting clinical symptoms, the potential for subtle imaging findings to be easily overlooked, and the need for specialized diagnostic testing. Once SIH is suggested by clinical history and/or supported by initial neuroim-aging, many patients may undergo initial nontargeted epidural blood patching with variable and indefinite benefit. However, data suggest that precise localization of the CSF leak or CSF-venous fistula (CVF) can lead to more effective and durable treatment strategies. Leak localization can be achieved using a variety of advanced diagnostic imaging techniques, although these may not be widely performed at nontertiary medical centers, leaving many patients with the potential for inadequate workup or treatment. This review describes imaging techniques including dynamic fluoroscopic and CT myelography as well as delayed MR myelography and treatment options including percutaneous, endovascular, and surgical approaches for SIH. These are summarized by an algorithmic framework for radiologists to approach the workup and treatment of patients with suspected SIH. The importance of a multidisciplinary approach is emphasized.

Catheter-guided multilevel epidural blood patches in an adolescent boy

Background

There is increasing evidence for the use of multilevel epidural catheter-guided blood patches to treat spontaneous cerebrospinal fluid leaks in adults. Yet, there are scarce data for their use in children. Furthermore, higher level epidural blood patches are uncommon in both adult and pediatric populations.

Case presentation

An adolescent boy with multilevel cerebrospinal fluid leaks associated with status migrainosus failed conservative pain management treatment. As he remained severely symptomatic, epidural blood patches were required to mitigate his symptoms. Given his multilevel leaks, a catheter-guided blood patch approach was used to treat multiple cervicothoracic and thoracolumbar leaks. After three separate uneventful blood patch procedures, the patient was free of symptoms. Other than some rebound intracranial hypertension, the patient maintained full neurological capacity without further complications. Following the resolution of treatment, he has not sought help for pain since his last blood patch over a year ago.

Conclusions

Multilevel catheter-guided blood patches have the potential to be administered to higher level spinal regions to the pediatric population suffering from multiple spontaneous cerebrospinal fluid leaks.

Early and Delayed Rebound Intracranial Hypertension following Epidural Blood Patch in a Case of Spontaneous Intracranial Hypotension

Background. Spontaneous intracranial hypotension (SIH) is a secondary headache that has been attributed to a cerebrospinal fluid (CSF) leak. It may resolve spontaneously or require conservative treatment. An epidural blood patch (EBP) with autologous blood is performed in cases exhibiting an inadequate response to conservative methods. Rebound intracranial hypertension (RIH) can develop following an EBP in up to 27% of patients. It is characterized by a change in the headache features and is often accompanied by nausea, blurred vision, and diplopia. Symptoms commonly begin within the first 36 hours, but could develop over days to weeks. It is important to differentiate this rebound phenomenon from unimproved SIH, as the treatment options differ. Case Presentation. Here, we present an interesting case of a patient with SIH who was treated with EBP and developed both immediate RIH after 24 hours and delayed RIH 3 weeks following EBP. Conclusions. Following EBP for treatment of SIH, new onset of headache having a different pattern and location should always be monitored for the occurrence of RIH. A lumbar puncture should be done if the symptoms of elevated CSF pressure become intolerable or if the diagnosis is uncertain. Lack of early diagnosis and treatment and differentiation from SIH can cause complications and could affect the optic nerves.

Brain Spontaneous Intracranial Hypotension Score for Treatment Monitoring After Surgical Closure of the Underlying Spinal Dural Leak

BACKGROUND

Spontaneous intracranial hypotension (SIH) is a debilitating condition requiring effective treatment; however, objective data on treatment response are scarce.

PURPOSE

To assess the suitability of the brain MRI-based SIH score (bSIH) for monitoring treatment success in SIH patients with a proven spinal cerebrospinal fluid (CSF) leak after microsurgical closure of the underlying dural breach.

METHODS

This retrospective cohort study included consecutive SIH patients with a proven spinal CSF leak, investigated at dedicated referral centre January 2012 to March 2020. The bSIH score integrates 6 imaging findings; 3 major (2 points) and 3 minor (1 point), and ranges from 0 to 9, with 0 indicating low and 9 high probability of spinal CSF loss. The score was calculated using brain magnetic resonance imaging (MRI) before and after surgical treatment of the underlying CSF leak. Headache intensity was registered on a numeric rating scale (NRS) (range 0-10).

RESULTS

In this study 52 SIH patients, 35 (67%) female, mean age 45.3 years, with a proven spinal CSF leak were included. The mean bSIH score decreased significantly from baseline to after surgical closure of the underlying dural breach (6.9 vs. 1.3, P < 0.001). A decrease in the NRS score was reported (8.6 vs. 1.2, P < 0.001).

CONCLUSION

The bSIH score is a simple tool which may serve to monitor treatment success in SIH patients after surgical closure of the underlying spinal dural leak. Its decrease after surgical closure of the underlying spinal dural breach indicates restoration of an equilibrium within the CSF compartment.

Greater occipital nerve blockade using ultrasound guidance for the headache of spontaneous intracranial hypotension - A case report

Background

Spontaneous intracranial hypotension occurs due to cerebrospinal fluid leakage from the spinal column, and orthostatic headache is the most common clinical presentation. Recent studies showed that bilateral greater occipital nerve blockade demonstrated clinical efficacy in relieving post-dural puncture headache after caesarean section.

Case

A 40-year-old male who presented severe orthostatic headache was consulted to our pain clinic from neurology department. He initially felt a dull nature pain over the whole occipital area which then spread over the frontal and parietal areas. His headache was combined with nausea and vomiting. An epidural blood patch was delayed until final cisternography, and bilateral greater occipital nerve blockade using ultrasound guidance was performed instead. After the blockade, the previously existing headache around the occipital and parietal areas disappeared completely, but mild headache persisted around the frontal area.

Conclusions

Greater occipital nerve blockade could be a good therapeutic alternative to improve headache resulting from spontaneous intracranial hypotension.

Successful management of spontaneous intracranial hypotension with epidural blood patch

Spontaneous intracranial hypotension (SIH) is characterised by postural headache and a cerebrospinal fluid (CSF) pressure of ≤6 cmH20 measured with the patient in the lateral decubitus position. Other symptoms include tinnitus, altered hearing, diplopia, photophobia, nausea and neck stiffness, and must not have occurred within a month of dural puncture. Symptoms typically remit after normalisation of CSF pressure or successful sealing of the CSF leak. An epidural blood patch (EBP) is a treatment option in those who have not responded to bed rest, fluids, non-steroidal anti-inflammatories or caffeine. We present a case of SIH successfully treated with both conservative measures and EBP. We compare our case with similar cases in the literature and summarise what is known about EBP for SIH to help clinicians take a more informed approach to managing such patients.

Idiopathic intracranial hypertension - a wider spectrum than headaches and blurred vision

BACKGROUND

The purpose of this study was to analyse less known clinical scenarios associated with idiopathic intracranial hypertension.

METHODS

The study involved analysis of magnetic resonance imaging signs of idiopathic intracranial hypertension in patients with spontaneous rhinoliquorrhoea (n = 7), in patients with temporal lobe epilepsy and surgically treated antero-inferior temporal lobe meningo-encephaloceles (n = 15), and in patients who developed clinical signs of idiopathic intracranial hypertension following the treatment of spontaneous intracranial hypotension (n = 7).

RESULTS

Three of six patients with spontaneous rhinoliquorrhoea and six of 15 operated patients with temporal lobe epilepsy due to temporal lobe meningo-encephaloceles showed magnetic resonance imaging signs of idiopathic intracranial hypertension and had a body mass index >30 kg/m². Rebound high pressure headaches and sings of idiopathic intracranial hypertension occurred in seven of 44 surgically treated spontaneous intracranial hypotension patients.

CONCLUSIONS

Magnetic resonance imaging findings should guide the clinician to consider (idiopathic) intracranial hypertension when patients develop spontaneous rhinoliquorrhoea, temporal lobe epilepsy secondary to temporal lobe meningoencephaloceles or high pressure headaches in spontaneous intracranial hypotension. Whether idiopathic intracranial hypertension must be regarded as a differential diagnosis or as a cause, or whether there are common pathophysiological pathways that lead to signs of idiopathic intracranial hypertension in this wider spectrum of disease is the focus of further study.

Spontaneous intracranial hypotension: diagnostic and therapeutic workup

Spontaneous intracranial hypotension (SIH) is an orthostatic headache syndrome with typical MRI findings among which engorgement of the venous sinuses, pachymeningeal enhancement, and effacement of the suprasellar cistern have the highest diagnostic sensitivity. SIH is in almost all cases caused by spinal CSF leaks. Spinal MRI scans showing so-called spinal longitudinal extradural fluid (SLEC) are suggestive of ventral dural tears (type 1 leak) which are located with prone dynamic (digital subtraction) myelography. As around half of the ventral dural tears are located in the upper thoracic spine, additional prone dynamic CT myelography is often needed. Leaking nerve root sleeves typically associated with meningeal diverticulae (type 2 leaks) and CSF-venous fistulas (type 3 leaks) are proven via lateral decubitus dynamic digital subtraction or CT myelography: type 2 leaks are SLEC-positive if the tear is proximal and SLEC-negative if it is distal, and type 3 leaks are always SLEC-negative. Although 30–70% of SIH patients show marked improvement following epidural blood patches applied via various techniques definite cure mostly requires surgical closure of ventral dural tears and surgical ligations of leaking nerve root sleeves associated with meningeal diverticulae or CSF-venous fistulas. For the latter, transvenous embolization with liquid embolic agents via the azygos vein system is a novel and valuable therapeutic alternative.

Clinical Outcomes Following Surgical Ligation of Cerebrospinal Fluid-Venous Fistula in Patients With Spontaneous Intracranial Hypotension: A Prospective Case Series

BACKGROUND

Cerebrospinal fluid-venous fistula (CVF) is a recently described cause of spontaneous intracranial hypotension (SIH). Surgical ligation of CVF has been reported, but clinical outcomes are not well described.

OBJECTIVE

To determine the clinical efficacy of surgical ligation for treatment of CVF.

METHODS

Outcomes metrics were collected in this prospective, single-arm, cross-sectional investigation. Inclusion criteria were as follows: diagnosis of SIH, demonstration of CVF on myelography, and surgical treatment of CVF. Pre- and postoperative headache severity was assessed with the Headache Impact Test (HIT-6), a validated headache scale ranging from 36 (asymptomatic) to 78 (most severe). Patient satisfaction with treatment was measured with Patient Global Impression of Change (PGIC).

RESULTS

Twenty subjects were enrolled, with mean postoperative follow-up at 16.0 ± 9.7 mo. All CVFs were located in the thoracic region (between T4 and T12). Pretreatment headache severity was high (mean HIT-6 scores 65 ± 6). Surgical treatment resulted in marked improvement in headache severity (mean HIT-6 change of -21 ± -9, mean postoperative HIT-6 of 44 ± 8). Of subjects with baseline headache scores in the most severe category, 83% showed a major improvement in severity (transition to the lowest 2 severity categories) after surgery. All subjects (100%) reported clinically significant levels of satisfaction with treatment (PGIC score 6 or 7); 90% reported the highest level of satisfaction. There were no short- or long-term complications or 30-d readmissions.

CONCLUSION

Surgical ligation is highly effective for the treatment of SIH due to CVF. Larger controlled trials with longer follow-up period are indicated to better assess its long-term efficacy and safety profile.

Rapid Cognitive Decline Secondary to CSF Venous Fistula With Postoperative Rebound Intracranial Hypertension and a Hyperintense Paraspinal Vein Sign Seen Retrospectively

A 56-year-old female with 2 prior Chiari decompressions presented with rapidly progressive cognitive decline. Brain magnetic resonance imaging, computed tomography myelogram, and prone digital subtraction myelography revealed signs of brain sag and left T9 perineural cysts but no cerebrospinal fluid leaks. Symptoms improved after multilevel blood patches but recurred. Lateral decubitus digital subtraction myelography revealed a spinal cerebrospinal fluid venous fistula (SCVF), which resolved after neurosurgeons ligated the nerve root. Rebound headaches with papilledema occurred on postoperative day 9 and then resolved 2 months after acetazolamide was started. A hyperintense paraspinal vein was seen retrospectively on T2-weighted magnetic resonance imaging with Dixon fat suppression sequencing. This case is unique in the acuity of cognitive decline secondary to SCVF. Acetazolamide at the time of treatment may potentially be used as prophylaxis for rebound intracranial hypertension. The hyperintense paraspinal vein may have utility in future diagnosis of SCVF.

It Is Just a Blood Patch: Considerations for Patients with Preexisting Intracranial Hypertension

Epidural blood patches are routine procedures interventional pain physicians perform for postdural puncture headaches (PDPH), whether it be due to the inadvertent wet tap from an epidural or a diagnostic lumbar puncture. Typically, these patients are relatively healthy and an epidural is relatively straightforward. However, there are cases complicated by a neurologic history such as benign intracranial hypertension. Here, we present a case of a patient with benign intracranial hypertension (BIH) that suffered a postdural puncture headache after a diagnostic lumbar puncture, with no documented opening pressure, continued on acetazolamide. There have only been a small number of documented cases of BIH complicated by PDPH. We discuss the medical management of BIH, how it can exacerbate a postdural puncture headache, our definitive management with an epidural blood patch, and our concerns of rebound intracranial hypertension. We demonstrate that treatment of PDPH in BIH is best managed with image-guided blood patches, with smaller volume of autologous blood, and at a slower rate.

Post-Dural Puncture Headache Evolving to a Subdural Hematoma: A Case Report

Introduction

Cervical epidural corticosteroid injections are frequently used for the treatment of subacute cervicobrachial pain. This therapy is considered safe, with the vast majority of the complications being minor and transient.

Case Report

We present a case of a woman in her fifties who suffered from cervicobrachialgia and received 2 cervical epidural corticosteroid infiltrations. On day 3 after the second infiltration, a new headache appeared and on day 16 a bilateral subdural hematoma was visualized on CT scan. Complete resorption of the hematoma was seen on day 25 without surgical intervention.

Discussion

Up until now, only 1 case report of an intracranial subdural hematoma after a cervical epidural steroid injection has been published. But several cases of an intracranial subdural hematoma after spinal, epidural, or combined spinal and epidural anesthesia have been reported. Physicians should be aware of this potentially dramatic complication since post‐dural puncture headache after any type of procedure can evolve into a subdural hematoma. Clinical differentiation between the two can be difficult; post‐dural puncture headache is characterized by relief of symptoms in the supine position and photophobia/phonophobia. A subdural hematoma should be considered if the headache changes in character, does not respond to treatment, or there are neurological signs such as nausea/vomiting and blurred vision. Immediate medical imaging should then be performed.

Spontaneous Intracranial Hypotension

BACKGROUND

Spontaneous intracranial hypotension (SIH) is an underdiagnosed disease. Its incidence is estimated at 5 per 100 000 persons per year.

METHODS

This review is based on a selective literature search in PubMed covering the years 2000-2019, as well as on the authors' personal experience.

RESULTS

The diagnostic and therapeutic methods discussed here are supported by level 4 evidence. SIH is caused by spinal leakage of cerebrospinal fluid (CSF) out of ventral dural tears or nerve root diverticula, or, in 2-5% of cases, through a fistula leading directly into the periradicular veins (CSF-venous fistula). In half of all patients, no CSF leak is demonstrable. A low CSF opening pressure on lumbar puncture is present in only one-third of patients; imaging studies are thus needed to confirm and localize a spinal CSF leak. Half of all patients in whom myelographic computed tomography (CT) reveals contrast medium reaching the epidural space have ventral dural tears, which tend to be located at upper thoracic spinal levels. Epidural blood patches applied under fluoroscopic or CT guidance can seal the CSF leak in 30-70% of patients, but 90% of patients with ventral dural tears will need operative closure. Some patients who have no visible epidural contrast medium on CT presumably do not have SIH, while others do, in fact, have a CSF leak from a diverticulum or a CSF-venous fistula and will need to have the site of the leak demonstrated with the aid of further studies, such as dynamic (subtraction) myelography in the lateral decubitus position.

CONCLUSION

The management of patients with SIH calls for complementary imaging studies to demonstrate the causative spinal CSF leak. Often, successful treatment requires surgical closure of the leak. In view of the sparse evidence available to date, controlled studies should be performed.

Assessing Spinal Cerebrospinal Fluid Leaks in Spontaneous Intracranial Hypotension With a Scoring System Based on Brain Magnetic Resonance Imaging Findings

Importance

Various signs may be observed on brain magnetic resonance imaging (MRI) in patients with spontaneous intracranial hypotension (SIH). However, the lack of a classification system integrating these findings limits decision making in clinical practice.

Objective

To develop a probability score based on the most relevant brain MRI findings to assess the likelihood of an underlying spinal cerebrospinal fluid (CSF) leak in patients with SIH.

Design, Setting, and Participants

This case-control study in consecutive patients investigated for SIH was conducted at a single hospital department from February 2013 to October 2017. Patients with missing brain MRI data were excluded. Three blinded readers retrospectively reviewed the brain MRI scans of patients with SIH and a spinal CSF leak, patients with orthostatic headache without a CSF leak, and healthy control participants, evaluating 9 quantitative and 7 qualitative signs. A predictive diagnostic score based on multivariable backward logistic regression analysis was then derived. Its performance was validated internally in a prospective cohort of patients who had clinical suspicion for SIH.

Main Outcomes and Measures

Likelihood of a spinal CSF leak based on the proposed diagnostic score.

Results

A total of 152 participants (101 female [66.4%]; mean [SD] age, 46.1 [14.3] years) were studied. These included 56 with SIH and a spinal CSF leak, 16 with orthostatic headache without a CSF leak, 60 control participants, and 20 patients in the validation cohort. Six imaging findings were included in the final scoring system. Three were weighted as major (2 points each): pachymeningeal enhancement, engorgement of venous sinus, and effacement of the suprasellar cistern of 4.0 mm or less. Three were considered minor (1 point each): subdural fluid collection, effacement of the prepontine cistern of 5.0 mm or less, and mamillopontine distance of 6.5 mm or less. Patients were classified into groups at low, intermediate, or high probability of having a spinal CSF leak, with total scores of 2 points or fewer, 3 to 4 points, and 5 points or more, respectively, on a scale of 9 points. The discriminatory ability of the proposed score could be demonstrated in the validation cohort.

Conclusions and Relevance

This 3-tier predictive scoring system is based on the 6 most relevant brain MRI findings and allows assessment of the likelihood (low, intermediate, or high) of a positive spinal imaging result in patients with SIH. It may be useful in identifying patients with SIH who are leak positive and in whom further invasive myelographic examinations are warranted before considering targeted therapy.

Headache, Cerebrospinal Fluid Leaks, and Pseudomeningoceles after Resection of Vestibular Schwannomas: Efficacy of Venous Sinus Stenting Suggests Cranial Venous Outflow Compromise as a Unifying Pathophysiological Mechanism

Background  Regardless of the operative approach, headache, cerebrospinal fluid (CSF) leaks, and pseudomeningoceles remain disproportionately common problems after surgery for vestibular schwannomas and have a significant negative impact on quality of life and potential to return to full employment. Recent work has raised the possibility that these problems may, in part, be related to acquired obstruction of cranial venous outflow. This article explores this idea further with respect to a group of patients with severe and intractable symptoms. Objective  The main objective of this article is to describe our experience diagnosing, investigating, and treating cranial venous outflow obstruction following translabyrinthine resection of vestibular schwannomas. Methods  Retrospective review of all patients ( n  = 9) at our institution referred for sigmoid sinus stenting following translabyrinthine surgery. Results  Headache resolved or improved after sigmoid stenting in all five patients in whom it was the primary symptom. CSF leak was the primary problem in two patients. In one, the leak was unchanged, but headache improved. In the other, the leak resolved, and headache improved. Two patients had symptomatic pseudomeningoceles and both resolved Conclusion  Assuming a meticulous approach to wound closure, a CSF leak following surgery for vestibular schwannoma can be viewed as a pathological, but essentially homeostatic, response to raised intracranial pressure caused by acquired obstruction to cranial venous outflow. Postoperative headache (from high or low intracranial pressure) and CSF leaks, therefore, may all respond to measures aimed at eliminating the obstructing lesion.

Rebound high-pressure headache after treatment of spontaneous intracranial hypotension: MRV study

BACKGROUND

Rebound high-pressure headaches may complicate treatment of spontaneous intracranial hypotension (SIH), but no comprehensive study of such patients has been reported and little is known about its frequency and risk factors. We therefore studied patients undergoing treatment for SIH and performed magnetic resonance venography (MRV) to assess for cerebral venous sinus stenosis, a risk factor for idiopathic intracranial hypertension.

METHODS

We studied a consecutive group of patients who underwent treatment for SIH. Rebound high-pressure headache was defined as a reverse orthostatic headache responsive to acetazolamide. MRV was obtained in all patients and lateral sinus stenosis was scored according to the system published by Higgins et al., with 0 being normal and 4 signifying bilateral signal gaps.

RESULTS

The mean age of the 46 men and 67 women was 45.9 years (range 13-71 years) at the time of onset of SIH. Rebound high-pressure headache was diagnosed in 31 patients (27.4%); 14% of patients with an MRV score of 0, 24% with a score of 1, and 46% with a score of 2 or 3 (p = 0.0092). Also, compared to SIH patients who did not develop rebound high-pressure headaches (n = 82), those with rebound high-pressure headaches were younger, more often female, and more often had an extradural CSF collection on spinal imaging.

CONCLUSIONS

Rebound high-pressure headache occurs in about one-fourth of patients following treatment of SIH and is more common in those with restriction of cerebral venous outflow.

Procedural predictors of epidural blood patch efficacy in spontaneous intracranial hypotension

BACKGROUND AND OBJECTIVE

Epidural blood patch (EBP) is a safe and effective treatment for spontaneous intracranial hypotension (SIH), but clinical and procedural variables that predict EBP efficacy remain nebulous.

METHODS

This study is an institutional review board-approved retrospective case series with dichotomized EBP efficacy defined at 3 months. The study included 202 patients receiving 604 EBPs; iatrogenic cerebrospinal fluid leaks were excluded.

RESULTS

Of the EBPs, 473 (78%) were single-level, 349 (58%) lumbar, 75 (12%) bilevel, and 56 (9%) multilevel (≥3 levels). Higher volume (OR 1.64; p<0.0001), bilevel (3.17, 1.91-5.27; p<0.0001), and multilevel (117.3, 28.04-490.67; p<0.0001) EBP strategies predicted greater efficacy. Only volume (1.64, 1.47-1.87; p<0.0001) remained significant in multivariate analysis. Site-directed patches were more effective than non-targeted patches (8.35, 0.97-72.1; p=0.033). Lower thoracic plus lumbar was the most successful bilevel strategy, lasting for a median of 74 (3-187) days.

CONCLUSIONS

In this large cohort of EBP in SIH, volume, number of spinal levels injected, and site-directed strategies significantly correlated with greater likelihood of first EBP efficacy. Volume and leak site coverage likely explain the increased efficacy with bilevel and multilevel patches. In patients with cryptogenic leak site, and either moderate disability, negative prognostic brain MRI findings for successful EBP, or failed previous lumbar EBP, a low thoracic plus lumbar bilevel EBP strategy is recommended. Multilevel EBP incorporating transforaminal administration and fibrin glue should be considered in patients refractory to bilevel EBP. An algorithmic approach to treating SIH is proposed.

Spontaneous Intracranial Hypotension: 10 Myths and Misperceptions

OBJECTIVE

To discuss common myths and misperceptions about spontaneous intracranial hypotension (SIH), focusing on common issues related to diagnosis and treatment, and to review the evidence that contradicts and clarifies these myths.

BACKGROUND

Recognition of SIH has increased in recent years. With increasing recognition, however, has come an increased demand for management by neurologists and headache specialists, some of whom have little prior experience with the condition. This dearth of practical experience, and lack of awareness of recent investigations into SIH, produces heterogeneity in diagnostic and treatment pathways, driven in part by outdated, confusing, or unsubstantiated conceptions of the condition. We sought to address this heterogeneity by identifying 10 myths and misperceptions that we frequently encounter when receiving referrals for suspected or confirmed SIH, and to review the literature addressing these topics.

METHODS

Ten topics relevant to diagnosis and treatment SIH were generated by the authors. A search for studies addressing SIH was conducted using PubMed and EMBASE, limited to English language only, peer reviewed publications from inception to 2018. Individual case reports were excluded. The resulting studies were reviewed for relevance to the topics in question.

RESULTS

The search generated 557 studies addressing SIH; 75 case reports were excluded. Fifty-four studies were considered to be of high relevance to the topics addressed, and were included in the data synthesis. The topics are presented in the form of a narrative review.

CONCLUSIONS

The understanding of SIH has evolved over the recent decades, leading to improvements in knowledge about the pathophysiology of the condition, diagnostic strategies, and expanded treatments. Awareness of these changes, and dispelling outdated misconceptions about SIH, is critical to providing appropriate care for patients and guiding future investigations going forward.

Imaging of Intracranial Pressure Disorders

Intracranial pressure (ICP) is the pressure inside the bony calvarium and can be affected by a variety of processes, such as intracranial masses and edema, obstruction or leakage of cerebrospinal fluid, and obstruction of venous outflow. This review focuses on the imaging of 2 important but less well understood ICP disorders: idiopathic intracranial hypertension and spontaneous intracranial hypotension. Both of these ICP disorders have salient imaging findings that are important to recognize to help prevent their misdiagnosis from other common neurological disorders.

Targeted Epidural Blood Patch Treatment for Refractory Spontaneous Intracranial Hypotension in China

Objective  An epidural blood patch (EBP) is the mainstay of treatment for refractory spontaneous intracranial hypotension (SIH). We evaluated the treatment efficacy of targeted EBP in refractory SIH. Methods  All patients underwent brain magnetic resonance imaging (MRI) with contrast and heavily T2-weighted spine MRI. Whole spine computed tomography (CT) myelography with non-ionic contrast was performed in 46 patients, and whole spine MR myelography with intrathecal gadolinium was performed in 119 patients. Targeted EBPs were placed in the prone position one or two vertebral levels below the cerebrospinal fluid (CSF) leaks. Repeat EBPs were offered at 1-week intervals to patients with persistent symptoms, continued CSF leakage, or with multiple leakage sites. Results  Brain MRIs showed pachymeningeal enhancement in 127 patients and subdural hematomas in 32 patients. One hundred fifty-two patients had CSF leakages on heavily T2-weighted spine MRIs. CSF leaks were also detected on CT and MR myelography in 43 and 111 patients, respectively. Good recovery was achieved in all patients after targeted EBP. No serious complications occurred in patients treated with targeted EBP during the 1 to 7 years of follow-up. Conclusions  Targeted and repeat EBPs are rational choices for treatment of refractory SIH caused by CSF leakage.