Clinical Presentation, Investigation Findings, and Treatment Outcomes of Spontaneous Intracranial Hypotension Syndrome: A Systematic Review and Meta-analysis

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.

Intracranial Hypotension Syndrome after Lumbar Drainage in Skull Base Surgery: Diagnosis and Correct Management

Lumbar drainage is commonly used in skull base surgery; however, very few cases of intracranial hypotension syndrome are reported to be caused by this procedure. We present a clinical case of lumbar drainage-assisted orbital and optic canal decompression surgery for a recurrent voluminous spheno-orbital meningioma, together with a literature review. A 49-year-old woman became confused and drowsy on postoperative day 3, after initially experiencing neurologic stability. Computed tomography (CT) scan of the head showed extradural frontotemporal fluid collection with moderate right to left midline shift. Magnetic resonance imaging (MRI) of the brain showed signs of intracranial hypotension, such as brain sagging and diffuse dural contrast enhancement. Conservative treatment with bed rest, aggressive hydration, steroids, and aminophylline led to progressive neurologic improvement. A systematic literature review was also performed, and previous reported cases were analyzed. Overall, neurosurgeons must be aware of the lumbar drainage-induced hypotension syndrome in skull base surgeries, because immediate diagnosis is essential for therapeutic decision-making. In this setting, conservative management is the first-line treatment as surgery may lead to severe complications.

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.

Treatment of postural headache occurred 26 days after spinal pain procedure - A case report

BACKGROUND

Cerebrospinal fluid (CSF) leakage may cause intracranial hypotension and postural headache. Secondary intracranial hypotension may result from an iatrogenic dural puncture or traumatic injury associated with pain procedures.

CASE

A 45-year-old male developed a headache 26 days after spinal pain procedure. Headache was characterized as postural, worsening with standing or sitting and improving while lying down. The pain did not resolve despite the administration of oral and intravenous analgesics. A spinal magnetic resonance imaging revealed epidural venous congestion and a suspicious CSF leak around the left L4/5 level. The patient received an epidural blood patch (EBP), the headache improved dramatically, and the patient was discharged.

CONCLUSIONS

Delayed postural headaches may not be directly related to pain management. Nevertheless, intracranial hypotension related to pain management should be suspected even in this case. If confirmed, quickly applying an EBP is an effective treatment option.

When does too little pressure become too much? A case of spontaneous intracranial hypotension presenting with acute loss of consciousness

Background

We present a unique case of spontaneous intracranial hypotension (SIH) presenting with acute collapse and loss of consciousness.

Case Description

The affected patient suffered an abrupt decline in level of consciousness several weeks after initial diagnosis. The patient was urgently transferred to a specialist neurosurgical unit. Imaging showed bilateral subdural fluid collections with significant associated local mass effect. The treating team faced a clinical conundrum with a lack of clarity as to whether this sudden deterioration was secondary to the local pressure effect on brainstem traction from reduced intracranial pressure. A decision was made to proceed with urgent burr-hole decompression of the bilateral subdural fluid collections.

Conclusion

After a protracted, complex postoperative course, the patient recovered to full functional independence. To the author's knowledge, this is the first case in literature describing successful surgical management of SIH, with bilateral burr-hole evacuation to relieve the paradoxical mass effect of bilateral subdural fluid collections.

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

BACKGROUND & OBJECTIVES

Spontaneous intracranial hypotension (SIH) is an underdiagnosed and debilitating condition caused by a spinal cerebrospinal fluid (CSF) leak. Although SIH can lead to substantial morbidity and disability, little data exists about patients' perspectives. Without hearing directly from patients, our understanding of the full experience of having SIH is limited, as is our ability to identify and use appropriate patient-reported outcome measures (PROMs) within clinical care and research. The purpose of this study was to conduct qualitative interviews with confirmed SIH patients to fully describe their experiences and identify relevant concepts to measure.

METHODS

Patients were recruited from an SIH specialty clinic at a large, U.S.-based healthcare center. Patients undergoing an initial consultation who were ≥ 18 years old, English-speaking, met the International Classification of Headache Disorders-3 criteria for SIH, and had a brain MRI with contrast that was positive for SIH were eligible to participate. During semi-structured qualitative interviews with a trained facilitator, participants were asked to describe their current SIH symptoms, how their experiences with SIH had changed over time, and the aspects of SIH that they found most bothersome. Analysts reviewed the data, created text summaries, and wrote analytic reports.

RESULTS

Fifteen participants completed interviews. Common symptoms reported by patients included headache, tinnitus, ear fullness/pressure/pain, and neck or interscapular pain. Patients reported that their symptoms worsened over the course of their day and with activity. The most bothersome aspect of SIH was disruption to daily activities and limits to physical activities/exercise, which were severe. With regard to symptoms, the most bothersome and impactful included physical pain and discomfort (including headache), as well as fatigue.

CONCLUSIONS

Patients reported a diverse set of symptoms that were attributed to SIH, with devastating impacts on functioning and high levels of disability. Researchers considering use of PROMs for SIH should consider inclusion of both symptom scales and aspects of functioning, and future work should focus on evaluating the validity of existing measures for this patient population using rigorous qualitative and quantitative methods in diverse samples. Additionally, these data can be used to assist clinicians in understanding the impacts of SIH on patients.

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.

Cerebrospinal Venous Fistula Presenting with Cognitive Decline: Systematic Literature Review and Report of Two Cases

OBJECTIVE

A cerebrospinal fluid (CSF) venous fistula (CVF) is an aberrant connection between the subarachnoid space and a vein resulting in CSF loss. The presentation and management of CVF with cognitive decline is incompletely understood.

METHODS

A systematic review was completed following the PRISMA guidelines. Articles that included at least 1 case of imaging-confirmed CVF with details on patient treatment were included. A separate review of cases of patients with spontaneous intracranial hypotension (SIH) with frontotemporal dementia (FTD) or dementia symptoms was also completed.

RESULTS

Ten CVF articles (69 patients; average age, 51.5 years) and 5 SIH with FTD or dementia articles (n = 41; average age, 55.9 years) were identified. Only 1 patients with CVF with cognitive abnormalities was identified. The most common symptom was headache in both reviews. Brain sag was identified in all patients, whereas CSF leak was identified in only 2 patients with SIH with FTD or dementia (4.9%). An epidural blood or fibrin glue patch was used in all patients with CVF and in 33 patients with SIH with FTD or dementia. Fifty-five patients with CVF (79.7%) and 27 patients with SIH with FTD or dementia (65.9%) had surgery.

CONCLUSIONS

The 2 cases and literature reviews show the difficulty in diagnosis and treatment of CVF with cognitive decline. Novel imaging techniques should be used in patients with cognitive decline in whom a CSF leak is suspected. Transvenous embolization or surgery should be considered before patching for treatment of CVF-induced brain sag and resulting dementia.

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.

Efficacy of Epidural Blood Patching or Surgery in Spontaneous Intracranial Hypotension: A Systematic Review and Evidence Map

BACKGROUND

Spontaneous intracranial hypotension is an important cause of treatable secondary headaches. Evidence on the efficacy of epidural blood patching and surgery for spontaneous intracranial hypotension has not been synthesized.

PURPOSE

Our aim was to identify evidence clusters and knowledge gaps in the efficacy of treatments for spontaneous intracranial hypotension to prioritize future research.

DATA SOURCES

We searched published English language articles on MEDLINE (Ovid), the Web of Science (Clarivate), and EMBASE (Elsevier) from inception until October 29, 2021.

STUDY SELECTION

We reviewed experimental, observational, and systematic review studies assessing the efficacy of epidural blood patching or surgery in spontaneous intracranial hypotension.

DATA ANALYSIS

One author performed data extraction, and a second verified it. Disagreements were resolved by consensus or adjudicated by a third author.

DATA SYNTHESIS

One hundred thirty-nine studies were included (median, 14 participants; range, 3-298 participants). Most articles were published in the past decade. Most assessed epidural blood patching outcomes. No studies met level 1 evidence. Most were retrospective cohort or case series (92.1%, n = 128). A few compared the efficacy of different treatments (10.8%, n = 15). Most used objective methods for the diagnosis of spontaneous intracranial hypotension (62.3%, n = 86); however, 37.7% (n = 52) did not clearly meet the International Classification of Headache Disorders-3 criteria. CSF leak type was unclear in 77.7% (n = 108). Nearly all reported patient symptoms using unvalidated measures (84.9%, n = 118). Outcomes were rarely collected at uniform prespecified time points.

LIMITATIONS

The investigation did not include transvenous embolization of CSF-to-venous fistulas.

CONCLUSIONS

Evidence gaps demonstrate a need for prospective study designs, clinical trials, and comparative studies. We recommend using the International Classification of Headache Disorders-3 diagnostic criteria, explicit reporting of CSF leak subtype, inclusion of key procedural details, and using objective validated outcome measures collected at uniform time points.

Traumatic pneumorrhachis associated with cerebral fluid leakage evaluated with magnetic resonance myelography

Attention should be paid to cerebrospinal fluid leakage in patients with pneumorrhachis associated with vertebral body trauma. If pneumorrhachis is detected, further imaging investigation and bed rest should be considered as appropriate.

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.

Rescue Epidural Saline Patch for Comatose Patients With Refractory Convexity Spontaneous Subacute Subdural Hematoma: Case Report

Objectives

Convexity spontaneous subacute subdural hematoma (CSSSH) frequently relapse after one or more surgical drainages. This may be due to spontaneous intracranial hypotension (SIH), for which the gold standard treatment is the epidural blood patch. In this study, we report 4 cases of refractory CSSSH treated with rescue epidural saline patch, although history and imaging studies showed no evidence of SIH.

Methods

All 4 patients received a lumbar saline epidural rescue patch for consciousness impairment associated with refractory CSSSH, and one is particularly detailed. No patient had typical radiologic signs of SIH or, on the contrary, uncal herniation that could have indicated intracranial hypertension.

Results

The Glasgow Coma Scale score improved significantly in the days after application of the epidural patch in 3 patients. All patients showed an improvement of the CT scan. Two patients underwent lumbar pressure measurement to confirm low values before the epidural injection, and for one, the intrathecal pressure profile during epidural patching is presented.

Discussion

An epidural patch may be considered in managing CSSSH with no uncal herniation, even in the absence of signs of SIH on brain and spinal imaging. Whether it should be combined with surgical evacuation or used as first-line therapy remains to be determined.

Continuous Epidural Saline Infusion for the Treatment of Spontaneous Intracranial Hypotension

OBJECTIVE

Spontaneous intracranial hypotension (SIH) is an increasingly recognized cause of orthostatic headache, but treatment strategies remain controversial. The epidural blood patch is a well-known and widely used treatment in patients with conservative treatment-resistant SIH, but symptoms may not improve even after multiple epidural blood patches, and resistant patients suffer from a lack of appropriate treatment options. Therefore, this study assessed the safety and efficacy of continuous epidural saline infusion (CESI) for SIH treatment.

METHODS

CESI was performed in 11 consecutive patients affected by conservative treatment-resistant SIH. Patient characteristics were obtained by reviewing medical records retrospectively. Headache intensity was assessed using the numerical rating scale (NRS), and changes in NRS before and after treatment were recorded.

RESULTS

The average treatment period for CESI was 21.3 ± 9.6 days, and the average follow-up period was 35.0 ± 30.2 months. CESI was without major complications or mortality, and no infections occurred, even without prophylactic antibiotics. The median NRS score before treatment was 10 points, improving to 5 points 1 day after infusion (P < 0.05), 2 points 1 week after infusion (P < 0.05), and 0 points at 3 months after infusion and the final follow-up. No patients have since experienced recurrence of orthostatic headaches.

CONCLUSIONS

CESI appears to be a safe and well-tolerated procedure for SIH. Further experience may demonstrate this technique to be a viable treatment option for SIH.

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.

Comparison of clinical characteristics with spontaneous intracranial hypotension complicated with subdural hematoma between surgical treatment and non-surgical treatment

OBJECTIVES

The aim of this current study was to analyze the possible surgical predictive factors about spontaneous intracranial hypotension (SIH) complicated with subdural hematoma (SDH).

METHODS

178 patients diagnosed with both SIH and SDH were retrospectively reviewed. All the participants were divided into as EBP group (BPG) and surgical treatment group (STG). The demographic, clinical manifestations, radiographic and treatment data of the two groups were collected and compared by the electrical medical history system.

RESULTS

The male patients accounted for the majority in the STG (77.88 %), which was significantly larger than those in the BPG(p = 0.004). Patients who regularly smoked and drunk alcohol in the STG group were significantly greater than those in the BPG group (p_(smoking)= 0.049, p_(drinking)= 0.014). The headache occurring in the temporal position in the STG accounted for 44.44 % which was significantly greater than those in the BPG (25.17 %, p = 0.040). The durations days of symptoms were 54.85 ± 34.78 and 33.72 ± 34.97 in the STG and BPG respectively (p = 0.005). The midline shift degree in the STG was also significantly greater than that in the BPG (p = 0.001). The largest hematoma depth in the STG was significantly greater than that in the BPG (p = 0.000). The frequency of blood patch in the STG was significantly greater than that in the BPG(p = 0022).

CONCLUSION

Male, unhealthy living habits, temporal headache, duration of headache, midline shift, hematoma depth and blood patch frequency were possible related factors with the poor outcome of blood patch and surgical treatment.

Intracranial hypotension in a breast cancer patient treated with epidural blood patches

We report the case of a patient with metastatic breast cancer who presented with an orthostatic headache. After a comprehensive diagnostic workup including MRI and lumbar puncture, we maintained the diagnosis of intracranial hypotension (IH). The patient was therefore treated with two consecutive non targeted epidural blood patches, resulting in the remission of IH symptoms for 6 months. IH in cancer patients is a rarer cause of headache than carcinomatous meningitis. As the diagnosis can be made by standard examination and the treatment is relatively simple and effective, IH deserves to be better known by oncologists.

Neuroimaging in the diagnosis and treatment of intracranial pressure disorders

OBJECTIVE

To review the clinical features, proposed pathophysiology, and the role of medical imaging in the diagnosis and treatment of idiopathic intracranial hypertension and spontaneous intracranial hypotension.

METHODS

The authors conducted a narrative review of the current literature on intracranial hypertension and hypotension syndromes, with a focus on imaging findings and role of neurointerventional radiology as a therapeutic option for these pathologies.

RESULTS

Idiopathic intracranial hypertension commonly presents in obese women of childbearing age, being headache and papilledema the main clinical manifestations. Characteristic radiological findings consist of increased cerebrospinal fluid around the optic nerve, partially empty sella turcica and stenosis of the transverse sinuses. Transverse sinus stenting is a treatment alternative that has proven valuable utility in the recent years. Spontaneous intracranial hypotension in most of cases presents with orthostatic headache and has predilection for female population. The typical radiological features in the brain consist of subdural fluid collections, enhancement of the dura, engorgement of the venous structures, pituitary enlargement, and sagging of the brain. In this pathology, a cerebrospinal fluid leak in the spine associated with a defect in the dura, meningeal diverticulum, or a cerebrospinal fluid-venous leak must be actively ruled out.

CONCLUSIONS

Neurologic complaints secondary to changes in intracranial pressure exhibit certain clinical features that in combination with fairly specific radiological patterns allow a highly accurate diagnosis. The diverse specialists in neurosciences should be aware of the multiple image modalities in the study of these syndromes as well as the treatment alternatives by neurointerventional radiology.

The SIH-EBP Score: A grading scale to predict the response to the first epidural blood patch in spontaneous intracranial hypotension

BACKGROUND

To develop and validate an easy-to-use scoring system to predict the response to the first epidural blood patching in patients with spontaneous intracranial hypotension.

METHODS

This study recruited consecutive patients with spontaneous intracranial hypotension receiving epidural blood patching in a tertiary medical center, which were chronologically divided into a derivation cohort and a validation cohort. In the derivation cohort, factors associated with the first epidural blood patching response were identified by using multivariable logistic regression modeling. A scoring system was developed, and the cutoff score was determined by using the receiver operating characteristic curve. The findings were verified in an independent validation cohort.

RESULTS

The study involved 280 patients in the derivation cohort and 78 patients in the validation cohort. The spontaneous intracranial hypotension-epidural blood patching score (range 0-5) included two clinical variables (sex and age) and two radiological variables (midbrain-pons angle and anterior epidural cerebrospinal fluid collections). A score of ≥3 was predictive of the first epidural blood patching response, which was consistent in the validation cohort. Overall, patients who scored ≥3 were more likely to respond to the first epidural blood patching (odds ratio = 10.3).

CONCLUSION

For patients with spontaneous intracranial hypotension-epidural blood patching score ≥3, it is prudent to attempt at least one targeted epidural blood patching before considering more invasive interventions.

The "Crossing Collection Sign": A Diagnostic Tool on Spine Magnetic Resonance Imaging For Localizing Cerebrospinal Fluid Leak

OBJECTIVE

The aim of the study is to determine whether the site of "cross" between ventral and dorsal spinal longitudinal extradural CSF collections (SLECs) seen on magnetic resonance imaging during initial workup of patients with suspected CSF leaks can predict the subsequently confirmed leakage site on computed tomography myelography or surgical repair.

METHODS

This was an institutional review board-approved, retrospective study performed from 2006 to 2021. Patients with SLECs who underwent total spine magnetic resonance imaging at our institution, followed by myelography and/or surgical repair for CSF leak, were included. Patients with incomplete workup including lack of computed tomography myelography and/or surgical repair and patients severely motion degraded imaging were excluded from our study. The site of cross between ventral and dorsal SLECs was defined as the "crossing collection sign" and was compared with the anatomically confirmed site of leak on myelography and/or at surgical repair.

RESULTS

Thirthy-eight patients met inclusion criteria with 18 females and 11 males ranging in age from 27 to 60 years (median, 40 years; interquartile range, 14 years). The crossing collection sign was seen in 76% of patients (n = 29). The distributions of confirmed CSF leak were as follows: cervical (n = 9), thoracic (n = 17), and lumbar spine (n = 3). The crossing collection sign predicted the site of CSF leak in 14 of 29 patients (48%) and was within 3-vertebral segments in 26 of 29 cases (90%).

CONCLUSIONS

The crossing collection sign can help prospectively identify spinal regions with highest likelihood for CSF leak in patients with SLECs. This can potentially help optimize the more invasive subsequent steps in the workup for these patients, including dynamic myelography and surgical exploration for repair.

Spontaneous Intracranial Hypotension Due to CSF Leak at Multiple Spinal Levels—A Case Report and Literature Review

Introduction Spontaneous intracranial hypotension (SIH) is a misdiagnosed condition characterized by low cerebrospinal fluid (CSF) volume and an orthostatic headache that worsens with upright posture due to CSF leak at spinal dural defects. SIH due to CSF leak at multiple spinal levels is a rare condition, and only a few cases have been reported in the literature. Here, we report a case of SIH with a CSF leak at multiple spinal levels. The treatment options and efficacy of epidural blood patch (EBP) injection were discussed in this article.

Case Report A 36-year-old man presented with complaints of orthostatic headache for 2 months and a computed tomography myelogram demonstrated CSF leaks at multiple spinal levels through the dural defects at C5-C6, C6-C7, C7-T1, T1-T2 levels, and at L1, L2, L3, and L4 vertebral levels on the left side. He was managed with a targeted EBP injection and he improved symptomatically within 24 hours of the EBP injection.

Summary SIH is an entity that results from CSF leakage, often through spinal dural defects due to mechanical tear by osteophyte complex, disc prolapse, connective tissue disorders, CSF-venous fistula, and leaking meningeal diverticula. SIH can result from single or multiple dural leaks, but spinal leaks at multiple levels are uncommon. To the best of our knowledge, a total number of 163 cases have been reported in the literature so far. With good success rates, targeted EBP injection with autologous blood is an effective treatment option for both single-level and multiple-level spinal leaks.

Outcome of epidural blood patch for imaging-negative spontaneous intracranial hypotension

BACKGROUND

Spontaneous intracranial hypotension is diagnosed by an abnormal finding in brain MRI, spinal imaging, or lumbar puncture. However, the sensitivity of each test is low. We investigated whether patients with suspected spontaneous intracranial hypotension and negative imaging findings would respond to epidural blood patch.

METHODS

We prospectively recruited patients with new-onset orthostatic headache admitted at the Samsung Medical Center from January 2017 to July 2021. In patients without abnormal imaging findings and no history of prior epidural blood patch, treatment outcome-defined as both 50% response in maximal headache intensity and improvement of orthostatic component-was collected at discharge and three months after epidural blood patch.

RESULTS

We included 21 treatment-naïve patients with orthostatic headache and negative brain and spinal imaging results who received epidural blood patch. After epidural blood patch (mean 1.3 times, range 1-3), 14 (66.7%) and 19 (90.5%) patients achieved both 50% response and improvement of orthostatic component at discharge and three months post-treatment, respectively. Additionally, complete remission was reported in 11 (52.4%) patients at three-month follow-up, while most of the remaining patients had only mild headaches. Among nine (42.9%) patients who underwent lumbar puncture, none had an abnormally low opening pressure (median 13.8 cm H₂O, range 9.2-21.5).

CONCLUSION

Given the high responder rates of epidural blood patch in our study, empirical epidural blood patch should be considered to treat new-onset orthostatic headache, even when brain and spinal imaging are negative. The necessity of lumbar puncture is questionable considering the high response rate of epidural blood patch and low rate of "low pressure."

Spontaneous intracranial hypotension: from cerebral venous thrombosis to neurosurgical treatment: a case series experience from a Brazilian tertiary health care center

BACKGROUND

 Spontaneous intracranial hypotension (SIH) is a secondary cause of headache and an underdiagnosed disease. The clinical presentation can be highly variable. It typically presents with isolated classic orthostatic headache complaints, but patients can develop significant complications such as cerebral venous thrombosis (CVT).

OBJECTIVE

 To report 3 cases of SIH diagnosis admitted and treated in a tertiary-level neurology ward.

METHODS

 Review of the medical files of three patients and description of clinical and surgical outcomes.

RESULTS

 Three female patients with SIH with a mean age of 25.6 ± 10.0 years old. The patients had orthostatic headache, and one of them presented with somnolence and diplopia because of a CVT. Brain magnetic resonance imaging (MRI) ranges from normal findings to classic findings of SIH as pachymeningeal enhancement and downward displacement of the cerebellar tonsils. Spine MRI showed abnormal epidural fluid collections in all cases, and computed tomography (CT) myelography could determine an identifiable cerebrospinal fluid (CSF) leak in only one patient. One patient received a conservative approach, and the other two were submitted to open surgery with laminoplasty. Both of them had uneventful recovery and remission in surgery follow-up.

CONCLUSION

 The diagnosis and management of SIH are still a challenge in neurology practice. We highlight in the present study severe cases of incapacitating SIH, complication with CVT, and good outcomes with neurosurgical treatment.

Spontaneous intracranial hypotension: updates from diagnosis to treatment

Spontaneous intracranial hypotension (SIH) is caused by spinal cerebrospinal fluid (CSF) leaks, which result in continued loss of CSF volume and multiple debilitating clinical manifestations. The estimated annual incidence of SIH is 5/100,000. Diagnostic methods have evolved in recent years due to improved understanding of pathophysiology and implementation of advanced myelographic techniques. Here, we synthesize recent updates and contextualize them in an algorithm for diagnosis and treatment of SIH, highlighting basic principles and points of practice variability or continued debate. This discussion includes finer points of SIH diagnosis, CSF leak classification systems, less common types and variants of CSF leaks, brain MRI Bern scoring, potential SIH complications, key technical considerations, and positioning strategies for different types of dynamic myelography. The roles of conservative measures, non-targeted or targeted blood patches, surgery, and recently developed endovascular techniques are presented.

Two Cases of Chronic Subdural Hematoma with Spontaneous Intracranial Hypotention Treated with Hematoma Drainage Followed by Epidural Blood Patch Under Intracranial Pressure Monitoring

Both chronic subdural hematoma (CSDH) and spontaneous intracranial hypotension (SIH) cause headaches. However, the etiologies are different: SIH headache is caused by decreased intracranial pressure (ICP), whereas CSDH headache results from increased ICP. Moreover, CSDH is treated by hematoma drainage, while SIH is treated by epidural blood patch (EBP). Treatment for the cases of combined SIH and CSDH is not well-established. Herein, we report two cases wherein ICP was monitored and safely controlled by EBP after hematoma drainage. Case 1: A 55-year-old man with progressive consciousness disturbance was diagnosed with bilateral CSDH. He underwent bilateral hematoma drainage; however, the headache became apparent during standing. We diagnosed SIH by diffuse pachymeningeal enhancement on brain MRI and epidural contrast medium leakage on CT myelography. Due to the re-enlargement of bilateral CSDH, we performed EBP after hematoma drainage and ICP monitor insertion. Finally, the headache and bilateral CSDH were resolved. Case 2: A 54-year-old man with persistent headache was diagnosed with bilateral CSDH. He underwent multiple hematoma drainage sessions. However, headache on standing persisted. We diagnosed SIH by diffuse pachymeningeal enhancement on brain MRI and epidural contrast medium leakage on CT myelography. Due to the re-enlargement of the left CSDH, we performed EBP after left hematoma drainage and ICP monitor insertion. Finally, the headache and bilateral CSDH were resolved. EBP after hematoma drainage and ICP monitoring was useful for SIH with bilateral CSDH. By monitoring ICP before EBP, the ICP was safely controlled and CSDH was resolved.

Thunderclap headache revealing dural tears with symptomatic intracranial hypotension: Report of two cases

Cerebrospinal fluid (CSF) leakage is considered the cause of spontaneous intracranial hypotension (SIH), an important etiology for new daily persistent headaches and a potentially life-threatening condition. Minor traumatic events rarely lead to CSF leakage, contrasting with iatrogenic interventions such as a lumbar puncture or spinal surgery, which are commonly complicated by dural tears. Most meningeal lesions are found in the cervicothoracic region, followed by the thoracic region, and rarely in the lumbar region, and extremely rarely in the sacral region. We describe two patients admitted to our hospital for severe headaches aggravated in the orthostatic position, with a recent history of minor trauma and sustained physical effort, respectively. In the first case, a bone fragment pierced an incidental congenital meningocele creating a dural fistula. An extensive extradural CSF collection, spanning the cervicothoracic region (C4-T10), was described in the second case. In both patients, the clinical evolution was favorable under conservative treatment.

[Spontaneous dural CSF fistula as a cause of intracranial hypotension syndrome. Case report and literature review]

Typical symptoms of spontaneous intracranial hypotension syndrome are severe headache, weakness, dizziness and inability to stay upright for a long time. Most often, this syndrome occurs due to CSF fistula in spinal space. Pathophysiology and diagnosis of this disease are poorly known for neurologists and neurosurgeons that can complicate timely surgical care. In case of correct diagnosis, we can identify the exact location of CSF fistula in 90% of cases. Treatment eliminates symptoms of intracranial hypotension and provides functional recovery. The purpose of this article is to describe the diagnostic algorithm and successful microsurgical treatment of a patient with spinal dural CSF fistula Th3-Th4 through posterolateral transdural approach.

Spinal dural cerebrospinal fluid fistula as a cause of spontaneous intracranial hypotension syndrome: Diagnosis and surgical treatment

Spontaneous intracranial hypotension (SIH) syndrome most often occurs following a cerebrospinal fluid (CSF) fistula that develops in the spinal space. Neurologists and neurosurgeons lack an understanding of the pathophysiology and diagnosis of this disease, which can make timely surgical care difficult. With the correct diagnostic algorithm, it is possible to identify the exact location of the liquor fistula in 90% of cases; subsequent microsurgical treatment can save the patient from the symptoms of intracranial hypotension and restore the ability to work. Female patient, 57 years old, was admitted with SIH syndrome. Magnetic resonance imaging (MRI) of the brain with contrast confirmed signs of intracranial hypotension. Computed tomography (CT) myelography was performed to pinpoint the location of the CSF fistula. The diagnostic algorithm and successful microsurgical treatment of a patient with spinal dural CSF fistula at the Th3-4 level using a posterolateral transdural approach. The patient was discharged on day 3 after the surgery when these complaints regressed completely. At the control examination of the patient 4 months postoperatively, there were no complaints. Identification of the cause and location of spinal the CSF fistula is a complex process that requires several stages of diagnosis. Examination of the entire back with MRI, CT myelography, or subtraction dynamic myelography is recommended. Microsurgical repair of a spinal fistula is an effective method for the treatment of SIH. The posterolateral transdural approach is effective in the repair of a spinal CSF fistula located ventrally in the thoracic spine.

Dural Entry Point of the Vertebral Artery: An Overlooked Route of Spinal CSF Leaks

Spontaneous intracranial hypotension (SIH) is no longer considered rare. Its estimated annual incidence is 5 cases per 100,000 individuals, which is half the incidence of subarachnoid hemorrhage. Epidural blood patch (EBP) is indicated for SIH patients who do not improve with conservative treatment. Accurate determination of the cerebrospinal fluid (CSF) leak site is critical for a successfully targeted EBP. We report the case of a 43-year-old woman with SIH secondary to CSF leakage at the craniovertebral junction dural entry point of the vertebral artery (VA). We treated the patient 2 months after the onset of symptoms. Fat-suppressed T2-weighted spinal magnetic resonance (MR) images revealed a massive epidural fluid collection around the upper thoracic spine. Extravasation of contrast medium through the left VA-dural entry point was clearly visible on computed tomographic myelography. A cervical EBP was injected through the C1-2 interlaminar space. The patient had a smooth recovery and was asymptomatic, with normal spinal MR findings, 6 months after treatment. The possibility of CSF leakage from the dural entry point of the VA should be considered in SIH patients. EBP targeted at the VA entry point is proposed as a safe and effective treatment.

Detection rate of MR myelography without intrathecal gadolinium in patients with newly diagnosed spontaneous intracranial hypotension

AIM

To evaluate the detection rate of magnetic resonance (MR) myelography without intrathecal gadolinium for cerebrospinal fluid (CSF) leakage in patients with newly diagnosed spontaneous intracranial hypotension (SIH) and to validate a published scoring system for predicting CSF leakage.

MATERIALS AND METHODS

This retrospective, observational, single-institution study included patients with newly diagnosed SIH between March 2015 and April 2021. Patients were included if they (a) had newly diagnosed SIH and (b) underwent initial brain MR imaging and preprocedural MR myelography with two- and three-dimensional turbo spin-echo sequences. Patients who underwent spine surgery or procedures including epidural injection and acupuncture were excluded. The detection rate was defined as the proportion of patients with a true-positive MR myelography result among all patients with confirmed CSF leakage. The interobserver agreement for the MR myelography results between two radiologists was analysed using weighted kappa statistics.

RESULTS

A total of 136 patients (mean age, 48 years; 70 women) with suspected SIH were included. Of these patients, 120 (88%, 120/136) were confirmed to have CSF leakage. Of the patients with confirmed CSF leakage, 90 (75%, 90/120) had epidural fluid collection. The detection rate of MR myelography for CSF leakage was 88% (105/120). The interobserver agreement between the two readers for detecting CSF leakage (κ = 0.76) or epidural fluid collection (κ = 0.76) on MR myelography was high. Among 24 patients with normal brain MR imaging results, 16 had CSF leakage (67%, 16/24).

CONCLUSIONS

Non-invasive MR myelography without intrathecal gadolinium should be considered to detect CSF leakage in patients with suspected SIH.

Diagnostic yield of MR myelography in patients with newly diagnosed spontaneous intracranial hypotension: a systematic review and meta-analysis

OBJECTIVES

To investigate the pooled diagnostic yield of MR myelography in patients with newly diagnosed spontaneous intracranial hypotension (SIH).

METHODS

A literature search of the MEDLINE/PubMed and Embase databases was conducted until July 25, 2021, including studies with the following inclusion criteria: (a) population: patients with newly diagnosed SIH; (b) diagnostic modality: MR myelography or MR myelography with intrathecal gadolinium for evaluation of CSF leakage; (c) outcomes: diagnostic yield of MR myelography or MR myelography with intrathecal gadolinium. The risk of bias was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. DerSimonian-Laird random-effects modeling was used to calculate the pooled estimates. Subgroup analysis regarding epidural fluid collection and meta-regression were additionally performed.

RESULTS

Fifteen studies with 643 patients were included. Eight studies used MR myelography with intrathecal gadolinium, and 11 used MR myelography. The overall quality of the included studies was moderate. The pooled diagnostic yield of MR myelography was 86% (95% CI, 80-91%) and that of MR myelography with intrathecal gadolinium was 83% (95% CI, 51-96%). There was no significant difference in pooled diagnostic yield between MR myelography and MR myelography with intrathecal gadolinium (p = 0.512). In subgroup analysis, the pooled diagnostic yield of the epidural fluid collection was 91% (95% CI, 84-94%). In meta-regression, the diagnostic yield was unaffected regardless of consecutive enrollment, magnet strength, or 2D/3D.

CONCLUSIONS

MR myelography had a high diagnostic yield in patients with SIH. MR myelography is non-invasive and not inferior to MR myelography with intrathecal gadolinium.

KEY POINTS

• The pooled diagnostic yield of MR myelography was 86% (95% CI, 80-91%) in patients with spontaneous intracranial hypotension. • There was no significant difference in pooled diagnostic yield between MR myelography and MR myelography with intrathecal gadolinium. • MR myelography is non-invasive and not inferior to MR myelography with intrathecal gadolinium.

Headache and Autonomic Dysfunction: a Review

PURPOSE OF REVIEW

We explore the anatomy of the central and peripheral autonomic pathways involved in primary headache as well as the mechanisms for secondary headache associated with disorders of the autonomic nervous system. The prevalence and clinical presentation of cranial and systemic autonomic symptoms in these conditions will be discussed, with a focus on recent studies.

RECENT FINDINGS

Several small studies have utilized the relationship between headache and the autonomic nervous system to identify potential biomarkers to aid in diagnosis of migraine and cluster headache. Headache in postural orthostatic tachycardia syndrome (POTS) has also been further characterized, particularly in its association with orthostatic headache and spontaneous intracranial hypotension (SIH). This review examines the pathophysiology of primary and secondary headache disorders in the context of the autonomic nervous system. Mechanisms of headache associated with systemic autonomic disorders are also reviewed.

Current perspectives on the recognition and diagnosis of low CSF pressure headache syndromes

INTRODUCTION

Headaches occur when cerebrospinal fluid (CSF) pressure drops following dural puncture or trauma or spontaneously. As the features of these headaches and their accompanying symptoms might not be typical, low CSF pressure headache syndromes, and spontaneous intracranial hypotension in particular, are often misdiagnosed and underdiagnosed.

AREAS COVERED

The aim of this narrative review is to summarize the most recent evidence regarding the clinical presentation and the diagnosis of low CSF pressure headache syndromes.

EXPERT OPINION

The clinical spectrum low CSF pressure headache syndromes varies significantly and key signs might be missing. Low CSF pressure headache syndromes should be included in the differential diagnosis of any case of refractory headache, even when the headache is not orthostatic, or there are normal neuroimaging findings, and/or lumbar puncture opening pressure is within normal limits. Future research should focus on controlled interventional studies on the treatment of low CSF pressure headache syndromes, which are currently lacking.

The first report on brain sagging dementia caused by a cranial leak: A case report

Objective

Brain Sagging Dementia (BSD) is an increasingly recognized syndrome for which diagnostic criteria recently were proposed. There have been no reports on BSD caused by a cranial leak. Here we present the first report on a patient with BSD caused by a cranial leak.

Case description

A 60-year old male patient was admitted with a 2-year history of orthostatic headache and gradually progressive cognitive and behavioral changes. Traditional treatments for spontaneous intracranial hypotension, including repeated epidural blood patches, failed. Brain imaging showed severe brain sagging, and intracranial pressure monitoring demonstrated intracranial hypotension. No leakage site was found. His past medical history revealed an accident where a ski pole struck his head at age ten. Due to progressive clinical decline, surgery was pursued. A cranial defect with an accompanying cerebrospinal fluid leak site representing the trauma from his childhood was found and repaired. He also was in need of a ventriculoperitoneal shunt. Following surgery, he improved and recovered completely.

Discussion

This case report illustrates that a cranial leak may cause BSD, even with a “lucid interval” between trauma and symptom debut spanning many years. Moreover, this report validates well the recently proposed BSD diagnostic criteria.

Survey of healthcare professionals’ knowledge, attitudes and practices regarding spontaneous intracranial hypotension

Objective

To assess the knowledge, attitudes and practices of healthcare professionals regarding the diagnosis and management of spontaneous intracranial hypotension (SIH).

Methods

We performed a cross-sectional, web-based survey of multiple healthcare professional groups in the UK from June to August 2021. There were 227 respondents to the survey, including 62 general practitioners, 39 emergency medicine physicians, 38 neurologists, 35 radiologists, 20 neurosurgeons, 18 anaesthetists and 15 headache nurse specialists. The majority of the respondents were at the consultant level and all worked in the UK National Health Service.

Results

Few general practitioners or emergency medicine physicians had ever been involved in the care of a patient with SIH or received teaching about SIH. Only 3 of 62 (4.8%) general practitioners and 1 of 39 (2.5%) emergency medicine physicians were confident in recognising the symptoms of SIH. Most neurologists were confident in recognising SIH and performed MRI of the brain as a first-line investigation, although there was variability in the urgency of the request, whether contrast was given or MRI of the spine organised at the same time. Most said they never or rarely performed lumbar puncture for diagnosis of SIH. Most neuroradiologists, but few general radiologists, were confident in interpreting imaging of patients with suspected SIH. Lack of access to epidural blood patching, personnel able to perform myelography, and established management pathways were identified by many respondents as barriers to the treatment of SIH.

Conclusions

We have identified a lack of awareness of SIH among non-specialists, several barriers to optimal treatment of SIH and a variation in current management pathways. The results highlight the need for education of healthcare professionals about SIH and the development of clinical practice guidelines to enable delivery of optimal and equitable care for patients with SIH.

Multiple etiologies of secondary headaches associated with arachnoid cyst, cerebrospinal fluid hypovolemia, and nontraumatic chronic subdural hematoma in an adolescent: A case report

Background:

Diagnosing the cause of headaches can be challenging. Even if intracranial lesions are found in a patient, careful assessment is essential for diagnosis, and treatment strategies will differ for each etiology.

Case Description:

A 16-year-old boy presented with sudden-onset headache which had lasted for 2 days. His headache was aggravated in the orthostatic position. The patient denied recent head trauma. He had been diagnosed with an arachnoid cyst (AC) in his right middle cranial fossa. Computed tomography (CT) revealed bilateral subdural effusions and slit-like lateral ventricles with no significant changes to the AC. After intravenous hydration followed by 2 days bed rest, his symptoms abated. He was diagnosed as having suffered spontaneous cerebrospinal fluid (CSF) hypovolemia. One month later, the patient experienced recurrent gradual onset headache and vomiting. CT revealed chronic right side subdural hematoma (SDH) with intracystic hemorrhage, which resulted in the elevation of intracranial pressure. An urgent hematoma evacuation was performed. He became symptom-free immediately after surgery. Postoperative follow-up CT showed no change in the AC and no recurrence of SDH. The lateral ventricles and subdural space were normal in size.

Conclusion:

We report a case presenting multiple types of secondary headaches, which were caused by intracranial hypotension or hypertension, with different etiologies. These were spontaneous CSF hypovolemia, nontraumatic intracystic hemorrhage form of AC, and nontraumatic chronic SDH. Although lesions seen at the time of initial diagnosis did not need surgical treatment, careful observation and repetitive imaging assessments might be useful for discovering unsuspected additional etiologies requiring surgical intervention.

Linear indices of ventricular volume on brain computed tomography as markers of effectiveness of epidural blood patch for spontaneous intracranial hypotension: A case report

RATIONALE

Epidural blood patch (EBP) is an effective treatment for spontaneous intracranial hypotension (SIH). However, its effectiveness can only be judged through subjective symptom improvement; no objective markers have been reported. Linear indices of ventricular volume on brain computed tomography (CT) may aid the objective evaluation of the effectiveness of EBP in patients with SIH.

PATIENT CONCERNS

A 45-year-old man was hospitalized due to a 3-week history of orthostatic headache, dizziness, and neck pain. He had visited a local emergency department at symptom onset. His neurological examination results were normal and vital signs were stable.

DIAGNOSES

Brain magnetic resonance imaging (MRI) revealed pachymeningeal enhancement in both convexities with a small subdural hematoma (SDH). Based on the clinical features and MRI findings, he was diagnosed with SIH complicated by SDH.

INTERVENTIONS

Non-targeted EBP was performed, first at the lumbar level and subsequently at the thoracic level. Linear indices of ventricular volume, including the Evans' index, frontal-occipital horn ratio, and bicaudate index, were measured through brain CT performed before and after EBP.

OUTCOMES

After lumbar EBP, there was no symptom relief or increase in linear indices of ventricular volume on brain CT. In contrast, the patient's symptoms completely resolved and the linear indices of ventricular volume increased after thoracic EBP.

LESSONS

The effectiveness of EBP, which is currently evaluated solely based on changes in symptom severity, can be assessed using linear indices of ventricular volume.

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.

Treating Spontaneous Intracranial Hypotension with an Anesthetic Modality: The Role of the Epidural Blood Patch

Background: Spontaneous intracranial hypotension (SIH) is a rare syndrome characterized by heterogeneity of presentation and prognosis, which can occasionally result in serious complications, such as the formation of subdural hematomas (SDHs). This case series aims to emphasize that SIH remains a diagnostic and therapeutic challenge; it can present with a broad clinical spectrum of symptoms, can lead to SDH and, if conservative treatment fails, an epidural blood patch (EBP) is a viable treatment option. Although the exact etiology of SIH is not known, it is believed to be due to cerebrospinal fluid (CSF) leak or a low CSF pressure. Case Series: Three patients (two males and one female) with ages ranging between 38 and 53 years old who presented with complaints of not only an orthostatic headache, but also a variety of symptoms of SIH, including the formation of two SDHs in one of them, were included in this series. These patients did not respond to conservative management and, subsequently, given the clinical and radiological evidence of SIH, were referred to the Anesthesiology Department for an EBP. Diagnostic workup was facilitated by imaging modalities, including magnetic resonance imaging (MRI) of the brain and spinal cord, prior to the EBP. All three patients were subjected to an EBP with an 18-gauge epidural needle. A total of between 30 and 43 mL of autologous blood was collected from the patients and was injected into the epidural space under strict aseptic conditions. Two lumbar (L₁-L₂, L₂-L₃) EBPs and one thoracic (T₁₁-T₁₂) EBP were performed on the three patients, respectively. All patients reported complete resolution of symptoms following the EBPs, while MRI improved substantially. Conclusions: This report describes three cases of SIH with CSF leak originating from the cervical, the thoracic and the lumbar level. The EBP restored CSF pressure and relieved the patients' persistent symptoms. MRI helps in revealing indirect signs of a low volume of CSF, though it may not be possible to locate the actual site of the leak. In conclusion, EBP is a well-accepted and beneficial treatment modality for SIH when conventional measures fail.

Effect of Intravenous Ketamine on Hypocranial Pressure Symptoms in Patients with Spinal Anesthetic Cesarean Sections: A Systematic Review and Meta-Analysis

BACKGROUND

Pregnant women are more likely to suffer post-puncture symptoms such as headaches and nausea due to the outflow of cerebrospinal fluid after spinal anesthesia. Because ketamine has the effect of raising intracranial pressure, it may be able to improve the symptoms of perioperative hypocranial pressure and effectively prevent the occurrence of hypocranial pressure-related side effects.

METHOD

Keywords such as ketamine, cesarean section, and spinal anesthesia were searched in databases including Medline, Embase, Web of Science, and Cochrane from 1976 to 2021. Thirteen randomized controlled trials were selected for the meta-analysis.

RESULTS

A total of 12 randomized trials involving 2099 participants fulfilled the inclusion criteria. There was no significant association between ketamine and the risk of headaches compared to the placebo (RR = 1.12; 95% CI: 0.53, 2.35; p = 0.77; I² = 62%). There was no significant association between ketamine and nausea compared to the placebo (RR = 0.66; 95% CI: 0.40, 1.09; p = 0.10; I² = 57%). No significant associations between ketamine or the placebo and vomiting were found (RR = 0.94; 95% CI: 0.53, 1.67; p = 0.83; I² = 72%).

CONCLUSION

Intravenous ketamine does not improve the symptoms caused by low intracranial pressure after spinal anesthesia in patients undergoing cesarean section.

Clinical Presentation and Outcomes of Acute Disseminated Encephalomyelitis in Adults Worldwide: Systematic Review and Meta-Analysis

Background

Acute disseminated encephalomyelitis (ADEM) is a rare demyelinating disorder that is often misdiagnosed. To improve early diagnosis, we performed a systematic review and meta-analysis of clinical features, outcomes for ADEM in adults.

Methods

The PubMed, Embase, Web of Science and Cochrane Library databases were searched for studies reporting the clinical features of adults with ADEM between January 1990 and May 2021. A random-effects meta-analysis model was used to pool data on clinical features and functional outcomes.

Results

Twelve studies examining 437 adults with ADEM met the inclusion criteria. Overall, the clinical features and diagnostic findings observed in more than two-thirds of the patients were white matter lesions [87.1%, 95% confidence interval (CI)=75-95.6], polyfocal onset (80.5%, 95% CI=50.5-98.9) and pyramidal signs (68.7%, 95% CI =40.0-91.9). The mortality rate was 7.8% (95% CI = 3.3–13.5), and the risk of residual deficits was 47.5% (95% CI = 31.8–63.4).

Conclusions

Adults with ADEM had worse outcomes than children. Clinicians should maintain high clinical suspicion for patients presenting with certain clinical features and diagnostic findings.

Efficacy of epidural blood patching or surgery in spontaneous intracranial hypotension: an evidence map protocol

BACKGROUND

Spontaneous intracranial hypotension (SIH) is a debilitating disorder caused by non-iatrogenic spinal cerebrospinal fluid leaks. SIH is increasingly recognized as an important treatable cause of secondary headaches. Treatment involves either epidural blood patching or surgery, which have considerable differences in their adverse event rates, recovery times, and cost. The objective of this evidence map is to understand the breadth of studies that investigate SIH treatment efficacy and to identify knowledge gaps to inform future research.

METHODS

This review will consider experimental, observational, and systematic review studies that assess the efficacy of epidural blood patching and surgery for the treatment of patients with SIH. Individual case studies, clinical guidelines, editorials, protocols, and studies that do not assess an intervention will not be included. English language studies will be included without limitation based on the date of publication. Databases to be searched include MEDLINE® (via Ovid), EMBASE (via Elsevier), and Web of Science™ (via Clarivate). Study selection will be performed independently by two investigators with extracted data to include study type, the number of patients included, patient descriptors, intervention characteristics, and outcome measure used. Data will be presented through a narrative summary aided by tabular and graphical formats in a manner that aligns with the objective of the evidence mapping review.

DISCUSSION

The overarching goal of this evidence map is to provide an improved understanding of the breadth of studies investigating SIH treatment efficacy in the literature and to thereby identify knowledge gaps that can inform future research directions.

TRIAL REGISTRATION

OSF Registry https://osf.io/nwju7 .