Volumetric response after closure of a spinal CSF leak in patients with spontaneous intracranial hypotension: a multicompartmental longitudinal study

BACKGROUND

Cerebrospinal fluid (CSF) loss in spontaneous intracranial hypotension (SIH) is accompanied by volume shifts between the intracranial compartments. This study investigated tricompartimental and longitudinal volume shifts after closure of a CSF leak.

METHODS

Patients with SIH and suitable pre-therapeutic and post-therapeutic imaging for volumetric analysis were identified from our tertiary care center between 2020 and 2023. The Bern SIH score was calculated. Pre-interventional and post-interventional volumetry encompassed the CSF, parenchymal and venous compartments (ie, venous sinus and choroid plexus volumes).

RESULTS

In total, 32 patients with SIH (49.7±16.0 years, 22 women) met inclusion criteria. The mean SIH score decreased between baseline (4.5±2.7) and early (2.7±2.3, <7 days after intervention), and also late follow-up (1.4±1.7, follow-up ≥7 days) after leak closure. This was accompanied by a significant increase in ventricular volume from 22.1 to 25.0 mL (P=0.01) at early follow-up, and 23.9 mL at later follow-up (P=0.080). In contrast, venous sinus volumes decreased from 13.8 to 9.6 mL (P=0.016) at early follow-up, and 10.0 mL (P=0.007) at late follow-up. No significant change in mean choroid plexus, total gray or total white matter volume was observed.

CONCLUSIONS

Closure of a spinal CSF leak leads to an early increase in ventricular CSF volume and a decrease in venous sinus volume. The results reflect the long-term convergence of the SIH score to normal values and indicate that permanent closure of a CSF leak induces a stable recompensation of the intracranial compartments without involving significant volume shifts within the cerebral parenchyma.

No evidence of intracranial hypotension in persistent post-traumatic headache: A magnetic resonance imaging study

BackgroundPersistent post-traumatic headache (PTH) is frequent, and intracranial hypotension may be an important cause of PTH. The present study aimed to examine whether magnetic resonance imaging (MRI) signs of intracranial hypotension are more frequent in people with persistent PTH than in healthy controls (HCs).MethodsAdults with persistent PTH attributed to mild traumatic brain injury and age- and sex-matched HCs attended a single non-contrast, brain MRI 3T session. Fluid attenuated inversion recovery T1- and T2-weighted sequences were acquired to assign a modified Bern score. The score ranges from 0 to 9 points, with higher scores indicating a greater probability of cerebrospinal fluid (CSF) leakage leading to intracranial hypotension. The primary outcome was the difference in modified Bern score between participants with persistent PTH and HCs. All images were examined by a certified neuroradiologist who was blinded to the group status.ResultsImaging data from 97 participants with persistent PTH and 96 age- and sex-matched HCs were eligible for analyses. A modified Bern score of ≤2 was present in 90 (93%) participants with persistent PTH and 85 (89%) HCs, indicating a low probability of CSF leak. None of the persistent PTH participants or the HCs had a score of >4. There were no significant differences in modified Bern scores between participants with persistent PTH and HCs.ConclusionsThere is a low prevalence of typical MRI Bern score signs of intracranial hypotension in PTH or HCs. Thus, intracranial hypotension is unlikely to be an underlying factor in persistent PTH attributed to mild traumatic brain injury.Trial RegistrationThe study was registered on ClinicalTrials.gov (identifier: NCT03791515). Date of registration 2018-12-29.

Microsurgical Repair of Ventral Cerebrospinal Fluid Leaks in Spontaneous Intracranial Hypotension: Efficacy and Safety of Patch-Sealing Versus Suturing

BACKGROUND AND OBJECTIVES

In patients with spontaneous intracranial hypotension (SIH), microsurgical repair is recommended in Type 1 (ventral) dural leaks, when conservative measures fail. However, there is lacking consensus on the optimal surgical technique for permanent and safe closure of ventral leaks.

METHODS

We performed a retrospective analysis of surgically treated SIH patients with Type 1 leaks at our institution between 2013 and 2023. Patients were analyzed according to the type of surgical technique: (1) Microsurgical suture vs (2) extradural and intradural patching (sealing technique). End points were resolution of spinal longitudinal epidural cerebrospinal fluid collection (SLEC), change in brain SIH-Score (Bern-Score), headache resolution after 3 months, surgery time, complications, and reoperation rates.

RESULTS

In total, 85 (66% women) patients with consecutive SIH (mean age 47 ± 11 years) underwent transdural microsurgical repair. The leak was sutured in 53 (62%) patients (suture group) and patch-sealed in 32 (38%) patients (sealing group). We found no significant difference in the rates of residual SLEC and resolution of headache between suture and sealing groups (13% vs 22%, P = .238 and 89% vs 94%, P = .508). No changes were found in the postoperative Bern-Score between suture and sealing groups (1.4 [±1.6] vs 1.7 [±2.1] P = 1). Mean surgery time was significantly shorter in the sealing group than in the suture group (139 ± 48 vs 169 ± 51 minutes; P = .007). Ten patients of the suture and 3 of the sealing group had a complication (23% vs 9%, P = .212), whereas 6 patients of the suture and 2 patients of the sealing group required reoperation (11% vs 6%, P = .438).

CONCLUSION

Microsurgical suturing and patch-sealing of ventral dural leaks in patients with SIH are equally effective. Sealing alone is a significantly faster technique, requiring less spinal cord manipulation and may therefore minimize the risk of surgical complications.

SIH-EBP score for prediction of efficacy of epidural blood patching in patients with spontaneous intracranial hypotension

BACKGROUND

Epidural blood patching (EBP) is the primary treatment for spontaneous intracranial hypotension (SIH), although multiple attempts may sometimes be necessary. The SIH-EBP score, with a cutoff of ≥3, predicts the response to the first EBP. However, its generalizability requires further confirmation. This study aims to validate the clinical utility of the SIH-EBP score and determine the optimal cutoff for predicting the response to the first EBP in an independent cohort of patients with SIH.

METHODS

This retrospective study included patients with SIH who received at least one EBP at a tertiary medical center. Clinical data were extracted from electronic medical records, and brain and spinal magnetic resonance images were reviewed.

RESULTS

Ninety-six patients (58 female [F]/38 male [M], mean age: 42.67 ± 10.16 years) were screened, with 49 (32 F/17 M, mean age: 41.20 ± 9.13 years) analyzed, including 30 (22 F/8 M, mean age: 41.10 ± 10.14 years) (61.2%) responders. There was a positive correlation between SIH-EBP scores and responder rates ( p = 0.001). A cutoff score of ≥3 was associated with a higher response rate than a score of <3 (80.0% vs 41.7%, p = 0.006) (sensitivity = 73.7%, specificity = 66.7%, accuracy = 69.4%). The optimal cutoff in this cohort was ≥2 (Area under curve (AUC) = 0.77, p < 0.001) (sensitivity = 52.6%, specificity = 90.0%, accuracy = 75.5%).

CONCLUSION

In this cohort, the SIH-EBP score correlated with response rates to the first EBP. Although a score of ≥3 remains a valid predictor of treatment response, a cutoff of ≥2 proved to be more accurate and specific. However, its practical use is limited by a sensitivity of 52.6%. Further studies are needed to verify its role in other populations.

Brainstem changes causing reversible RBD in patients with spontaneous intracranial hypotension: a longitudinal neuroimaging study

OBJECTIVE

This study aimed to investigate the prevalence of REM sleep behavior disorder (RBD) in patients with spontaneous intracranial hypotension (SIH) and longitudinally assess the effects of epidural blood patch (EBP) treatment on brainstem structures using a neuroimaging approach.

METHODS

Twenty-two participants (10 SIH patients and 12 controls) underwent 3-Tesla Magnetic Resonance Imaging (MRI) scans. Midbrain and pons areas were measured on T1-weighted scans at baseline in both groups and three months after the first EBP in SIH patients to determine any MRI structural changes. The RBD Single-Questionnaire was used to screen SIH patients with symptoms suggestive of RBD for polysomnographic (PSG) recording.

RESULTS

Half of the SIH patients (5/10) exhibited PSG-confirmed RBD. Baseline evaluation revealed deep brain swelling (DBS) on MRI scans in SIH-RBD patients. Following EBP treatment, significant changes in midbrain and pons morphometry were associated with complete clinical remission of RBD. Cross-sectional analysis showed larger midbrain and pons areas in SIH patients (with and without RBD) compared to controls. A midbrain area of 200 mm2 was identified as a cut-off value distinguishing SIH patients (with and without RBD) from controls individually. Longitudinal analysis demonstrated lower midbrain areas at follow-up compared to baseline in SIH patients.

DISCUSSION

The study suggests that brainstem morphometric changes may underlie reversible RBD in SIH patients. Midbrain area measurement could serve as a dynamic biomarker for SIH, particularly in the presence of RBD, offering insights for clinical practice.

Image-guided Epidural Blood Patching and Fibrin Glue Occlusion of Cerebrospinal Fluid Leaks and Venous Fistulas

There have been major advances in the diagnosis and treatment of spontaneous intracranial hypotension (SIH). While once thought to be a rare condition, the occurrence is not uncommon if diagnosed adequately. Our greater understanding of SIH is based on three main points: (1) awareness of the various types of spontaneous spinal cerebrospinal fluid (CSF) leaks; (2) advanced myelography with the precision to detect dural tears and CSF-venous fistulas; and (3) updated treatment techniques of epidural patching, embolization, and surgery. This review discusses the various types of epidural patching for CSF leaks.

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: Diagnosis, Management, and Outcomes

Cerebrospinal fluid (CSF) leaks are a challenging condition characterized by the loss of CSF, leading to severe orthostatic headaches and other debilitating symptoms. Diagnosis and management require a multifaceted approach involving clinical evaluation, imaging, and various treatment modalities to improve patient outcomes and quality of life.

Neuraxial biomechanics, fluid dynamics, and myodural regulation: rethinking management of hypermobility and CNS disorders

Individuals with joint hypermobility and the Ehlers-Danlos Syndromes (EDS) are disproportionately affected by neuraxial dysfunction and Central Nervous System (CNS) disorders: such as Spontaneous Intracranial Hypotension (SIH) due to spinal cerebrospinal fluid (CSF) leaks, Upper Cervical Instability (UCI; including craniocervical or atlantoaxial instability (CCI/AAI)), Occult Tethered Cord Syndrome (TCS), Chiari Malformation (CM) and Idiopathic Intracranial Hypertension (IIH). The neuraxis comprises the parts of the nervous system (brain, nerves, spinal cord) along the craniospinal axis of the body. Neuraxial tissue includes all tissue structures that comprise, support, sheath, and connect along the neuraxis and peripheral nerves. Altered mechanical loading or vascular supply of neural structures can adversely impact neural health and conductivity, with local and remote effects on inflammation, venous congestion, and muscle control. With EDS characterized by altered structure of the connective tissues found throughout the body including the neural system, altered mechanical properties of the central nervous system (CNS) and its surrounding tissue structures are important considerations in the development and diagnostics of these CNS disorders, as well as response to therapeutic interventions. Experts have identified a need for neuraxial curriculum in medical education and hypermobility-adapted treatment approaches in pain management, neurosurgery, anesthesiology, hematology, gastrointestinal surgery, dermatology, cardiology, dentistry, gastroenterology, allergy/immunology, physical therapy, primary care, radiology and emergency medicine. This paper reviews the interactions between neuraxial biomechanics and pathology related to CNS disorders seen commonly with EDS. First, we provide a concise synthesis of the literature on neuraxial kinematics and fluid dynamics. We then discuss the interplay of these biomechanics and their involvement in clinically-relevant diagnoses and overlapping symptom presentations, modeling physiological reasoning to highlight knowledge gaps, support clinical decision-making, improve multidisciplinary management of hypermobility-associated complexity, and add weight to the call for medical education reform.

Spontaneous Intracranial Hypotension and Dural Ectasia in Marfan Syndrome: An Illustrative Case Successfully Treated with Steroid Therapy and Literature Review

BACKGROUND

Spontaneous intracranial hypotension (SIH) is a rare and frequently misdiagnosed disorder characterized by a low volume of cerebrospinal fluid (CSF) caused by the leakage of CSF through the spinal dural membrane. Patients with Marfan Syndrome (MS) and other connective tissue disorders are at an increased risk for dural ectasia, which may predispose them to spontaneous CSF leaks due to the structural weakness of their dural membranes. The management of SIH in MS patients is debated. Conservative measures, an epidural blood patch (EBP), and surgical treatments are the options generally provided.

METHODS

Herein, we report on the case of a 52-year-old female affected by MS, genetically confirmed, with a two-month history of sudden-onset, "thunderclap" headache, worsened in an upright position and horizontal diplopia. A Computed Tomography (CT) scan of the brain showed a bilateral chronic subdural hematoma, slit ventricles, and a caudal descent of the brainstem without overt tonsillar herniation. The Magnetic Resonance Imaging (MRI) scan of the whole spine revealed dural ectasia in the lumbosacral area and presacral perineural cyst without extradural CSF collection. The case was successfully managed with bed rest and high-dose corticosteroid therapy. Then, we discuss the pertinent literature, consisting of 25 papers dealing with the treatment of SIH in patients affected by MS.

RESULTS

The literature review yielded 25 papers dealing with SIH management in patients with MS, including 28 patients overall; 21 patients underwent EBP, of whom 7 patients had multiple procedures. Overall, in 23 cases (82%), the symptoms improved. In three cases, the patients were managed conservatively with bed rest. In three of these cases, there was an improvement. In one case, the surgical fenestration of two lumbar intradural spinal meningeal cysts was performed and the patient improved after the procedure. Our patient underwent 15 days of steroid therapy (dexamethasone iv 12 mg/day for 7 days, then reduced to 4 mg/day) and intravenous hydration (Ringer lactate 1500 mL/day). In ten days, the symptoms disappeared. At the 6-month follow-up, the patient was in good clinical condition, and a CT scan showed an almost complete regression of the bilateral subdural hematoma.

CONCLUSIONS

The management of SIH in MS patients is still challenging. Patients with connective tissue disorders such as MS are at an increased risk for SIH. Few studies have assessed the management of these patients and different strategies. Our case and the available literature provide further data for this type of case.

Minimally Invasive Approaches to Spinal Cerebrospinal Fluid Leak Repair: Current Strategies and a Novel Technique

Spinal cerebrospinal fluid (CSF) leaks can be caused by tears in the dura and are challenging to treat. Traditional methods of treating spinal CSF leakage include nonsurgical management, epidural blood patches (EBP), and direct surgical repair. Minimally invasive surgery (MIS) is rapidly progressing within neurosurgery due to its advantages for patient safety and comfort. Existing MIS techniques to spine surgery utilize a rigid endoscope, which has limitations when reaching smaller areas requiring greater degrees of visualization. The simultaneous use of a flexible endoscope and wearable heads-up display (wHUD) improves access and visualization in these small areas while allowing the surgeon to maintain optimal ergonomics. In this article, we review minimally invasive approaches to spine surgery and the management of spinal CSF leaks. We also demonstrate a novel minimally invasive technique utilizing flexible endoscopy and a wHUD to treat a case of recurrent CSF leak. We describe the successful utilization of this technology and provide the groundwork for future practitioners to incorporate this approach into their practice.

Research productivity on spontaneous intracranial hypotension: A bibliometric analysis

Introduction

Spontaneous intracranial hypotension (SIH) is an important cause of devastating headaches and caused by CSF-leaks in the spine.

Research question

The aim of this analysis was to gain an overview of the progress of research on SIH over time. The global publication landscape relating to SIH was analyzed and comparisons between regions were made.

Material and methods

A bibliometric analysis was performed by searching for research articles on SIH in PubMed published between 1983 and 2022. Countries responsible for the publications were ranked by the sum of citations. An average annual growth rate was calculated and the density of SIH publications per 100 000 physicians was determined.

Results

We identified 974 articles. In 1983 only one SIH patient was reported; in 2021 the number of patients had increased to 4230. The average annual growth rate of SIH publications during this period was 12.7%. The most common publication type were case reports (n = 570). The most common medical specialty of the first author was neurology (n = 251) followed by neurosurgery (n = 250) and radiology (n = 191). Although most publications originated from the United States of America (USA), South Korea had the highest density of SIH investigators (37.86 publications per 100 000 medical doctors). The most cited paper (296 citations) was published in 2006 in JAMA (USA).

Discussion and conclusion

Research on SIH has increased exponentially over the past four decades. The international community of SIH researchers is growing, and with it the opportunities for global networks involved in research, treatment, and patient education.

The choroid plexus maintains adult brain ventricles and subventricular zone neuroblast pool, which facilitates poststroke neurogenesis

The brain's neuroreparative capacity after injuries such as ischemic stroke is partly contained in the brain's neurogenic niches, primarily the subventricular zone (SVZ), which lies in close contact with the cerebrospinal fluid (CSF) produced by the choroid plexus (ChP). Despite the wide range of their proposed functions, the ChP/CSF remain among the most understudied compartments of the central nervous system (CNS). Here, we report a mouse genetic tool (the ROSA26iDTR mouse line) for noninvasive, specific, and temporally controllable ablation of CSF-producing ChP epithelial cells to assess the roles of the ChP and CSF in brain homeostasis and injury. Using this model, we demonstrate that ChP ablation causes rapid and permanent CSF volume loss in both aged and young adult brains, accompanied by disruption of ependymal cilia bundles. Surprisingly, ChP ablation did not result in overt neurological deficits at 1 mo postablation. However, we observed a pronounced decrease in the pool of SVZ neuroblasts (NBs) following ChP ablation, which occurs due to their enhanced migration into the olfactory bulb. In the middle cerebral artery occlusion model of ischemic stroke, NB migration into the lesion site was also reduced in the CSF-depleted mice. Thus, our study establishes an important role of ChP/CSF in regulating the regenerative capacity of the adult brain under normal conditions and after ischemic stroke.

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

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

Factors to predict recurrence after epidural blood patch in patients with spontaneous intracranial hypotension

OBJECTIVES

This study aimed to identify predictors for the recurrence of spontaneous intracranial hypotension (SIH) after epidural blood patch (EBP).

BACKGROUND

Epidural blood patch is the main treatment option for SIH; however, the characteristics of patients who experience relapse after successful EBP treatment for SIH remain understudied.

METHODS

In this exploratory, retrospective, case-control study, we included 19 patients with SIH recurrence after EBP and 36 age- and sex-matched patients without recurrence from a single tertiary medical institution. We analyzed clinical characteristics, neuroimaging findings, and volume changes in intracranial structures after EBP treatment. Machine learning methods were utilized to predict the recurrence of SIH after EBP treatment.

RESULTS

There were no significant differences in clinical features between the recurrence and no-recurrence groups. Among brain magnetic resonance imaging signs, diffuse pachymeningeal enhancement and cerebral venous dilatation were more prominent in the recurrence group than no-recurrence group after EBP (14/19 [73%] vs. eight of 36 [22%] patients, p = 0.001; 11/19 [57%] vs. seven of 36 [19%] patients, p = 0.010, respectively). The midbrain-pons angle decreased in the recurrence group compared to the no-recurrence group after EBP, at a mean (standard deviation [SD]) of -12.0 [16.7] vs. +1.8[18.3]° (p = 0.048). In volumetric analysis, volume changes after EBP were smaller in the recurrence group than in the no-recurrence group in intracranial cerebrospinal fluid (mean [SD] -11.6 [15.3] vs. +4.8 [17.1] mL, p = 0.001) and ventricles (mean [SD] +1.0 [2.0] vs. +2.0 [2.5] mL, p = 0.003). Notably, the random forest classifier indicated that the model constructed with brain volumetry was more accurate in discriminating SIH recurrence (area under the curve = 0.80 vs. 0.52).

CONCLUSION

Our study suggests that volumetric analysis of intracranial structures may aid in predicting recurrence after EBP treatment in patients with SIH.

Spinal Cerebrospinal Fluid Leak Localization with Dynamic Computed Tomography Myelography: Tips, Tricks, and Pitfalls

Locating spinal cerebrospinal fluid (CSF) leaks can be a diagnostic dilemma for clinicians and radiologists, as well as frustrating for patients. Dynamic computed tomography myelography (dCTM) has emerged as a valuable tool in localizing spinal CSF leaks, aiding in accurate diagnosis, and guiding appropriate management. This article aims to provide insights into the technique, tips, tricks, and potential pitfalls associated with dCTM for spinal CSF leak localization. By understanding the nuances of this procedure, clinicians can optimize the diagnostic process and improve patient outcomes.

Effects of surface profile on porcine dural mechanical properties

BACKGROUND

Cerebrospinal fluid leakage through the spinal meninges is difficult to diagnose and treat. Moreover, its underlying mechanism remains unknown. Considering that the dura mater is structurally the strongest and outermost membrane among the three-layered meninges, we hypothesized that a dural mechanical tear would trigger spontaneous cerebrospinal fluid leakage, especially when a traumatic loading event is involved. Thus, accurate biomechanical properties of the dura mater are indispensable for improving computational models, which aid in predicting blunt impact injuries and creating artificial substitutes for transplantation and surgical training.

METHOD

We characterized the surface profile of the spinal dura and its mechanical properties (Young's moduli) with a distinction of its inherent anatomical sites (i.e., the cervical and lumbar regions as well as the dorsal and ventral sides of the spinal cord).

FINDINGS

Although the obtained Young's moduli exhibited no considerable difference between the aforementioned anatomical sites, our results suggested that the wrinkles structurally formed along the longitudinal direction would relieve stress concentration on the dural surface under in vivo and supraphysiological conditions, enabling mechanical protection of the dural tissue from a blunt impact force that was externally applied to the spine.

INTERPRETATION

This study provides fundamental data that can be used for accurately predicting cerebrospinal fluid leakage due to blunt impact trauma.

The choroid plexus maintains ventricle volume and adult subventricular zone neuroblast pool, which facilitates post-stroke neurogenesis

The brain's neuroreparative capacity after injuries such as ischemic stroke is contained in the brain's neurogenic niches, primarily the subventricular zone (SVZ), which lies in close contact with the cerebrospinal fluid (CSF) produced by the choroid plexus (ChP). Despite the wide range of their proposed functions, the ChP/CSF remain among the most understudied compartments of the central nervous system (CNS). Here we report a mouse genetic tool (the ROSA26iDTR mouse line) for non-invasive, specific, and temporally controllable ablation of CSF-producing ChP epithelial cells to assess the roles of the ChP and CSF in brain homeostasis and injury. Using this model, we demonstrate that ChP ablation causes rapid and permanent CSF volume loss accompanied by disruption of ependymal cilia bundles. Surprisingly, ChP ablation did not result in overt neurological deficits at one-month post-ablation. However, we observed a pronounced decrease in the pool of SVZ neuroblasts following ChP ablation, which occurs due to their enhanced migration into the olfactory bulb. In the MCAo model of ischemic stroke, neuroblast migration into the lesion site was also reduced in the CSF-depleted mice. Thus, our study establishes an important and novel role of ChP/CSF in regulating the regenerative capacity of the adult brain under normal conditions and after ischemic stroke.

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

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

Patient-reported symptomatology and its course in spontaneous intracranial hypotension - Beware of a chameleon

OBJECTIVE

Although orthostatic headache is the hallmark symptom of spontaneous intracranial hypotension (SIH), patients can present with a wide range of different complaints and thereby pose a diagnostic challenge for clinicians. Our aim was to describe and group the different symptoms associated with SIH and their course over time.

METHODS

We retrospectively surveyed consecutive patients diagnosed and treated for SIH at our institution from January 2013 to May 2020 with a specifically designed questionnaire to find out about their symptomatology and its course.

RESULTS

Of 112 eligible patients, 79 (70.5%) returned the questionnaire and were included in the analysis. Of those, 67 (84.8%) reported initial orthostatic headaches, whereas 12 (15.2%) denied having this initial symptom. All except one (98.7%) patients reported additional symptoms: most frequently cephalic pressure (69.6%), neck pain (68.4%), auditory disturbances (59.5%), nausea (57%), visual disturbances (40.5%), gait disturbance (20.3%), confusion (10.1%) or sensorimotor deficits (21.5%). Fifty-seven (72.2%) patients reported a development of the initial symptoms predominantly in the first three months after symptom onset. Age and sex were not associated with the symptomatology or its course (p > 0.1).

CONCLUSION

Although characteristic of SIH, a relevant amount of patients present without orthostatic headaches. In addition, SIH can manifest with non-orthostatic headaches at disease onset or during the course of the disease. Most patients report a wide range of associated complaints. A high degree of suspicion is crucial for an early diagnosis and targeted treatment.

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.

A Novel Window Into Human Vascular Remodeling and Diagnosing Carotid Flow Impairment: The Petro-Occipital Venous Plexus

Background Adaptive arterial remodeling caused by flow reduction from downstream stenosis has been demonstrated in animal studies. The authors sought to determine whether inward remodeling from downstream stenosis also occurs in humans and is detectable by ex vacuo expansion of the Rektorzik venous plexus (RVP) surrounding the petrous internal carotid artery. Methods and Results The authors analyzed 214 intracranial magnetic resonance imaging examinations that included contrast-enhanced vessel wall imaging. RVP symmetry was qualitatively assessed on vessel wall imaging. RVP thickness (RVPT) was measured on the thicker side if asymmetric or randomly assigned side if symmetric. Maximum stenosis (M1 or intracranial internal carotid artery) was measured. Posterior communicating artery and A1 diameters (>1.0 mm and 1.5 mm, respectively) defined adequate collateral outflow when proximal to the stenosis. Seventy-two patients had stenosis downstream from RVPT measurements. For those without adequate outflow (38 of 72), 95.0% with RVPT ≥1.0 mm had ≥50% stenosis compared with only 5.6% with RVPT <1.0 mm. For these 72 patients, higher RVPT (RVPT ≥1.0 mm versus <1.0 mm) and absent adequate outflow were associated with greater downstream stenosis (P<0.001) using multivariate regression. For patients with downstream stenosis without adequate outflow, asymmetric RVP thickening was associated with greater ipsilateral stenosis (P<0.001, all had ≥46% stenosis) when stenosis was unilateral and greater differences in stenosis between sides (P=0.005) when stenosis was bilateral. Conclusions Inward internal carotid artery remodeling measured by RVPT or RVP asymmetry occurs as downstream stenosis approaches 50%, unless flow is preserved through a sufficiently sized posterior communicating artery or A1, and may serve as a functional measure of substantial flow reduction from downstream stenosis.

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.

Small spheno-ethmoidal meningoencephalocele versus ethmoidal mucocele in spontaneous intracranial hypotension

Background

Meningoencephalocele is defined as an abnormal sac of brain tissue and meninges extending beyond natural skull margins, often leading to cerebrospinal fluid (CSF) leakage. When this condition arises in the spheno-ethmoidal region, the diagnosis becomes more challenging as it can be mistaken for other nasal pathologies, such as mucocele.

Research question

We show in this case report a non-congenital sphenoethmoidal meningoencephalocele causing rhinoliquoral fistula and spontaneous intracranial hypotension.

Results

this 65-year-old woman presented with sporadic rhinoliquorrhoea associated with orthostatic headache, nausea and dizziness. Brain MRI revealed a small lesion of an ethmoidal sinus, which was successfully treated with endoscopic endonasal surgery. Histology confirmed the presence of meningoencephalic tissue positive for S100 protein on immunohistochemistry.

Conclusions

When dealing with lesions of the paranasal sinuses in contact with the anterior skull base, rhinoliquorrhoea presence suggests meningoencephalocele. In dubious cases, a proper workup, including a thorough clinical history and neurological examination, specific imaging, and a direct search of CSF-like markers, is essential to support the differential diagnosis. In such cases, a transnasal endoscopic surgical approach is recommended to obtain a final histological diagnosis and to perform eventual dural plastic surgery.

Case report: Post-traumatic Tourette syndrome resolving with treatment of jugular venous narrowing; reconciling organic brain dysfunction following whiplash trauma with the absence of direct brain injury

We describe a man aged 33 years who developed multiple symptoms, personality change, and a severe tic disorder following a road traffic accident, which were undiminished for 3 years until jugular venous narrowing between the styloid process of the skull and the transverse process of the C1 vertebra was treated by surgical decompression. Immediately following surgery, his abnormal movements almost completely resolved, with no regression in 5 years of follow-up. Vigorously debated at the time was whether or not his condition represented a functional disorder. Unrecognized throughout his illness, however, was a complaint of intermittent, profuse discharge of clear fluid from his nose that began on the day of the accident and continued up to the time of surgery, after which it was substantially reduced. This outcome reinforces the idea that jugular venous narrowing can cause or perpetuate a cerebrospinal fluid leak. It suggests that the interaction between these two pathological defects may have a profound effect on brain function in the absence of any demonstrable brain lesion. It invites a reevaluation of normal head and neck venous anatomy. It should strike a cautionary note in the diagnosis of functional illness. It invites exploration of a remediable structural cause for Tourette syndrome.

A Rare Case of Cerebrospinal Fluid Rhinorrhea from Canal of Stenberg

Background: A spontaneous cerebrospinal leak from Sternberg's canal with meningoencephalocele is a very rare clinical entity. Endoscopic repair of the defect is challenging and crucial in identifying the defect. The aim of this case report is to highlight the presence and management with endoscopic surgery in repairing Sternberg canal. Case: 40-year-old woman presents with spontaneous CSF rhinorrhea with no predisposing factors. CT imaging and MRI showed osteodural defect in the lateral recess of sphenoid with meningoencephalocoele lateral to the foramen rotundum. Endoscopic transethmoidal - transphenoidal - transpterygoid approach was used to repair the defect, and patient is well post-operative with least complication from the intervention surgery. Conclusion: Endoscopic approach proved to be the best and safest method in localizing the defect and closure of the leak. Angled scopes and image guided system were used to identify the precise location of the leak.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-022-03347-z.

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.

Life changing response to successive surgical interventions on cranial venous outflow: A case report on chronic fatigue syndrome

Recognition of similarities between chronic fatigue syndrome and idiopathic intracranial hypertension (IIH) has raised suggestions that they might be connected, with chronic fatigue syndrome representing a mild version of IIH, sharing many of its symptoms, but without the signature features of elevated intracranial pressure that characterize the complete syndrome. A further development of this idea factors in the effects of a cerebrospinal fluid leak, a known complication of IIH, to explain cases where symptoms seem out of proportion to the apparent physiological disturbance. Cranial venous outflow obstruction has been proposed as the pathological substrate. We describe a patient with multiple symptoms, including headache and disabling fatigue, in which this model guided investigation and treatment. Specifically, CT and catheter venography identified focal narrowings of both jugular and the left brachiocephalic veins. Treatment of brachiocephalic obstruction was not feasible. However, in separate surgical procedures, relief of jugular venous obstruction produced incremental and significant clinical improvements which have proven durable over the length of follow-up. We suggest that investigating chronic fatigue syndrome under this model might not only bring benefit to individual patients but also will provide new insights into IIH and its relationship with spontaneous intracranial hypotension.

Spontaneous Intracranial Hypotension and Spinal Epidural CSF Leaks: Diagnosis and Management

Spontaneous intracranial hypotension from spinal cerebrospinal fluid leak is a condition that often presents as orthostatic headaches. Diagnosis and localisation of spinal CSF leaks remain difficult despite multiple imaging modalities that can be used to aid identification. These include traditional CT myelography and MRI as well as newer techniques such as dynamic and digital subtraction myelography. Leaks can be classified into types and optimal localisation and management techniques vary by type of leak. Localisation of a leak can aid in targeting treatment such as an epidural blood patch if conservative measures fail. Where unsuccessful, repeated blood patches and novel techniques can be used to improve patient symptoms. Much of this condition is not well understood and evidence is lacking, with many avenues for potential research.

Unusual neuroimaging findings in spontaneous intracranial hypotension

PURPOSE

The most common neuroimaging manifestations of patients suffering from spontaneous intracranial hypotension (SIH) include subdural fluid collections, enhancement of the pachymeninges, engorgement of venous structures, pituitary hyperemia, sagging of the brainstem, and cerebellar hemosiderosis. However, infrequently patients may present with separate neuroradiological findings which could be easily mistaken for other pathology.

METHODS

We describe patients who presented with unique neuroimaging findings who were eventually found to have a spinal CSF leak or venous fistula. Relevant clinical history and neuroradiology findings are presented, and a relevant review of the literature is provided.

RESULTS

We present six patients with a proven CSF leak or fistula who presented with dural venous sinus thrombosis, compressive ischemic injury, spinal hemosiderosis, subarachnoid hemorrhage, pial vascular engorgement, calvarial hyperostosis, and spinal dural calcifications.

CONCLUSION

Radiologists should be familiar with atypical neuroimaging manifestations of SIH in order to avoid misdiagnosis and guide the clinical trajectory of the patient towards accurate diagnosis and eventual cure.

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.

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.

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.

Spontaneous intracranial hypotension complicated by unilateral subdural hematoma, coma, and the rare Kernohan's notch phenomenon

Spontaneous intracranial hypotension (SIH) is a highly underdiagnosed condition with a wide range of manifestations. Although SIH has traditionally been viewed as having a benign disease course, recent evidence suggests otherwise. In this case report, we present a 71-year-old woman who was previously treated with a tapered dose of corticosteroids for an episode of SIH with behavioral manifestations. In this current report, we present her second episode which was complicated by a unilateral sub-acute subdural hematoma leading to loss of consciousness and coma. While the patient regained full consciousness and recovered considerably, she still suffers from ipsilateral hemiparesis as a result of Kernohan's notch phenomenon 2 years post-hospitalization. To the author's knowledge, this is the first case to involve persistent motor deficit after the resolution of SIH. We believe that surgical hematoma evacuation prior to addressing the cerebrospinal fluid leak may have contributed to aggregated downward displacement of the brain precipitating Kernohan's notch phenomenon.

Subarachnoid hemorrhage caused by spontaneous intracranial hypotension: two rare cases report

BACKGROUND

Spontaneous intracranial hypotension (SIH) combined with subarachnoid hemorrhage (SAH) has rarely been reported. Herein, we report two patients with SIH who suffered from diffuse non-aneurysmal SAH and expanded the symptom spectrum of SIH.

CASE PRESENTATION

(1) A 55-year-old male was diagnosed with SIH based on orthostatic headache and diffuse pachymeningeal enhancement on brain MRI. One more month later, his headache was exacerbated, and brain CT showed diffuse SAH. Lumber puncture showed bloody cerebrospinal fluid (CSF) with a low CSF pressure of 20 mmH₂O after a 30 mL intrathecal injection of saline. The patient was treated with a lumbar epidural blood patch and recovered. (2) A 41-year-old male presented with orthostatic headache and nuchal pain. The brain CT scan confirmed the diagnosis of SAH. Brain MRI revealed diffuse dural thickening and bilateral frontoparietal subdural fluid collection. Lumber puncture showed bloody CSF with low CSF pressure. Then, an epidural blood patch was performed with satisfactory results.

CONCLUSION

Dilation and rupture of intracranial venous structures might play significant roles in SIH combined with SAH. We should be alert to SIH patients who develop a new persistent severe headache without relief after lying down or a suddenly changed state of consciousness.

Full Endoscopic Repair of Spontaneous Ventral Cerebrospinal Fluid Leaks in the Spine: Systematic Review of Surgical Treatment Options and Illustrative Case

BACKGROUND

Spontaneous spinal cerebrospinal fluid (CSF) leaks are a rare entity that can lead to intracranial hypotension and associated headaches, meningismus, and patient debility. Surgical treatment may be necessary for patients who do not respond to conservative management. Surgical repair of CSF leaks located in the ventral thoracic spine traditionally require an invasive, open approach.

METHODS

We describe the case of a patient with a ventral thoracic spontaneous spinal CSF leak associated with a ventral bony osteophyte successfully treated with spinal endoscopy. We also provide a systematic review of the literature to better understand outcomes of this approach.

RESULTS

A total of 55 patients were included in the systematic review. The study designs found in the literature review included case reports (66.7%), retrospective cohorts (22.2%), and prospective cohorts (11.1%). Of the studies reporting data, 50% of studies stated they used an open posterior approach to the dural defect, while 37.5% reported using an open anterior approach to the pathology. Only 1 (12.5%) study reported using an endoscope. Most studies (62.5%) used primary closure of the dura in their technique, while 37.5% reported using a local tissue graft (fat or muscle) or a dural sealant for their closure technique, and 25% of studies reported using a dural substitute for their closure technique. Overall mean clinical follow-up was 19.8 months.

CONCLUSIONS

The endoscopic approach described here for treatment of this rare entity allows for removal of bony spicules/osteophytes and dural repair without the morbidity associated with traditional open dorsolateral or ventrolateral approaches.

Lumbar epidural blood patch: An effective treatment for intracranial hypotension

Background:

The literature has demonstrated the efficacy of lumbar epidural blood patch (LEBP) in the management of spontaneous intracranial hypotension (SIH). However, the underlying pathophysiology of such management remains unclear. In this study, we aim to evaluate the utility of LEBP injections in the management of SIH and develop a potential management algorithm used in the triage and management of SIH patients.

Methods:

We retrospectively examined the clinical case notes of 14 patients with SIH (age: 25–69 years) who were managed with LEBP injections during the year of 2016–2021. We evaluated the presenting symptoms of each selected patient and radiological findings as well as treatment outcomes. Our aim is to evaluate the effectiveness of LEBP in the treatment of SIH patients through follow-up clinical and imaging assessment.

Results:

About 93% of patients describe the presence of headache at presentation, while 43% describe it as being of an orthostatic nature. All patients demonstrated typical findings on magnetic resonance imaging brain. Treatment success assessed through symptomatic improvement and radiological resolution was found in 85% of our patients at a 2-month interval.

Conclusion:

LEBP injection is an effective method of management in patients with a diagnosis of SIH. It should be considered in all SIH patients irrespective of whether a “dural leak” can be localized through radiological investigations.

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.

Secondary Headache Disorders: Approach, Workup, and Special Considerations for Select Populations

Headache is one of the most common diagnoses in neurology. A thorough understanding of the clinical presentation of secondary headache, which can be life-threatening, is critical. This review provides an overview of the diagnostic approach to a patient with headache, including discussion of "red," "orange," and "green" flags. We emphasize particular scenarios to help tailor the clinical workup to individual circumstances such as in pregnant women, when particular attention must be paid to the effects of blood pressure and hypercoagulability, as well as in older adults, where there is a need for higher suspicion for an intracranial mass lesion or giant cell arteritis. Patients with risk factors for headache secondary to alterations in intracranial pressure, whether elevated (e.g., idiopathic intracranial hypertension) or decreased (e.g., cerebrospinal fluid leak), may require more specific diagnostic testing and treatment. Finally, headache in patients with COVID-19 or long COVID-19 is increasingly recognized and may have multiple etiologies.

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.

Case report: Epidural blood patches are effective in treating intracranial hypotension due to a subarachnoid-pleural fistula

Background

Intracranial hypotension (IH) is usually associated with cerebrospinal fluid (CSF) leakage and/or CSF hypotension, and epidural blood patch (EBP) therapy has been proven to be effective for treating spontaneous IH and post-dural puncture headaches. Tarlov cysts (TCs) are common lesions of the sacral spine. They have rarely been reported in thoracic locations and are even less common in the posterior mediastinum, which can lead to their misdiagnosis as neurogenic tumors.

Case presentation

Here, we report the case of a 60-year-old woman who developed an orthostatic headache after the thoracoscopic resection of a TC in the posterior mediastinum that was presumed to be a schwannoma preoperatively. The patient was finally diagnosed with IH caused by a subarachnoid-pleural fistula (SPF) and was cured by targeted EBP treatment.

Conclusion

This is a case to show that a single targeted EBP treatment is effective for a patient with IH caused by an SPF after thoracoscopic resection of a TC. This case reminds us to be vigilant that a TC may be masquerading as a posterior mediastinal neurogenic tumor, and a detailed examination should be performed to identify it before deciding on a surgical procedure. In addition, postural headache after thoracoscopic spinal surgery should be alert to the possibility of IH induced by an SPF. Once it occurs, early treatment is necessary, and targeted EBP treatment can serve as a safe and effective alternative when conservative treatment fails.

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.

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.

Cerebrospinal fluid hypotension following fall in a child: Case report

CSF hypotension arises in the context of a leak of CSF which causes negative intracranial pressure. Sacral fractures result from high-energy trauma which are frequently underdiagnosed. A ten-year-old boy presented with hip pain, after a fall. He mobilized both lower limbs, reported no leg pain, irradiation nor lack of sphincter control. The neurological examination was normal. When asked to stand, he began biparietal headache, nausea and vomiting, which improved laying down. CT scan showed an occult intrasacral meningocele; the MRI revealed collections of CSF along the spine, a S3 fracture with potential laceration of the meningocele and opening of a CSF fistula. Our diagnosis was the CSF hypotension, secondary to the fistula opening. The diagnosis was challenging. The child first presented with symptoms of CSF hypotension without evident cause. The discovery of the meningocele led us to hypothesize the opening of a fistula, a rare diagnosis, later confirmed by MRI.

Dural sac shrinkage signs on spinal magnetic resonance imaging indicate overdrainage after lumboperitoneal shunt for idiopathic normal pressure hydrocephalus

Background:

We previously found the usefulness of dural sac shrinkage signs (DSSSs), which are the anterior shift of the spinal cord and dura mater behind the cord, detected by magnetic resonance imaging (MRI) at the thoracic level for the diagnosis of spontaneous intracranial hypotension (IH). This is a retrospective survey on the usefulness of DSSSs for the early detection of iatrogenic IH caused by overdrainage through a lumboperitoneal shunt (LPS) for patients with idiopathic normal pressure hydrocephalus (INPH).

Methods:

Forty-five INPH patients had an LPS using a pressure programmable valve equipped with an anti-siphon device.

Results:

Nine patients complained of orthostatic headache after the LPS, indicating IH due to overdrainage, which persisted for more than a week in three patients and 2–7days in six patients. The headache was transient/ nonorthostatic in ten patients and absent in 26 patients. The DSSSs and accompanying enlargement of the venous plexus were observed in all three patients with prolonged orthostatic headaches. Only the anterior shift of the dura mater was observed in 1 (4%) among 25 patients who had short-term orthostatic headache, transient/ nonorthostatic headache, or absent headache, and underwent spinal MRI. A patient with prolonged severe orthostatic headache with both DSSSs eventually developed intracranial subdural effusion and underwent tandem valve surgery, which provided a quick improvement of symptoms. The DSSSs on thoracic MRI also disappeared promptly.

Conclusion:

DSSSs may serve as objective signs for the diagnosis of IH due to overdrainage through an LPS for INPH.

Cerebrospinal fluid hypovolemia syndrome mimicking ocular myasthenia gravis: A case report

Purpose

Cerebrospinal fluid hypovolemia syndrome (CHS) is a rare clinical entity that can be caused by spontaneous cerebrospinal fluid (CSF) leakage. The aim of this study is to report a rare case of CHS after a traffic accident in a patient who presented with diplopia and ptosis with fluctuation and was initially diagnosed with ocular myasthenia gravis.

Observeations

A 29-year-old man exhibited fluctuating left ptosis and diplopia after a traffic accident. Although he was suspected of having myasthenia gravis and was treated using oral pyridostigmine bromide, his symptoms did not improve. He also had orthostatic headaches and malaise after the accident. His symptoms were suspected to be associated with traumatic cerebrospinal fluid hypovolemia. After 1000-mL fluid replacement, his diplopia and ptosis improved, and orbital T2-weghted MRI detected a high-signal zone around the optic nerve. We diagnosed him with oculomotor nerve paresis associated with cerebrospinal fluid hypovolemia. The symptoms, including ptosis, diplopia, orthostatic headaches, and malaise, disappeared after epidural blood patch therapy.

Conclusions and Importance

When treating patients with fluctuating ocular symptoms, such as diplopia and ptosis, who have a history of trauma and orthostatic headaches, the possibility of CHS should be considered in the differential diagnosis.

Prediction of Target Epidural Blood Patch Treatment Efficacy in Spontaneous Intracranial Hypotension Using Follow-Up MRI

Objectives: Epidural blood patching (EBP) is the mainstay therapy for spontaneous intracranial hypotension (SIH). MRI is used for evaluating spinal CSF leakage. Post-EBP MRI has been. shown to be effective in predicting the efficacy of EBP. However, there are few reports on how post-EBP MRI findings may change with time. The aim of this study was to evaluate the relationship between post-EBP MRI findings at different time points and the corresponding effectiveness of EBP. Methods: We retrospectively reviewed 63 SIH patients who had received target EBP. All patients received an MRI follow-up within 10 days (post-EBP MRI) and at 3 months after EBP (3-month MRI). A sub-group analysis was performed at different post-EBP MRI time points (0–2, 3–6, and 7–10 days). The relationships between the post-EBP MRI findings and the EBP effectiveness were evaluated. Results: Thirty-five (55.56%) patients were assigned to the EBP-effective group, and 28 (44.44%) were assigned to the EBP non-effective group according to the 3-month MRI. Compared to the EBP non-effective group, the EBP-effective group had significantly lower numbers of spinal CSF leakage in the post-EBP MRI (4.49 vs. 11.71; p = 0.000) and greater numbers of leakage improvement (7.66 vs. 2.96; p = 0.003). For patients who received post-EBP MRI during periods of 0–10, 0–2, 3–6, and 7–10 days, the cutoff values of numbers of spinal CSF leakage for predicting EBP failure were 4, 6, 4, and 5, respectively, with an AUC above 0.77. Conclusion: By using post-EBP MRI, which only takes approximately 20 min, predicting EBP efficacy became possible in SIH patients. This study provides cutoff values of numbers of spinal CSF leakage at different follow-up times to serve as clues of if further EBP is needed, which provides the novelty of the current study.

Airplane flights triggering spontaneous intracranial hypotension: Observations from the Danish headache centre

Objective

Spontaneous intracranial hypotension (SIH) manifests as orthostatic headache, which can be confirmed by radiological signs of low intracranial pressure on magnetic resonance imaging of the brain. The most common mechanisms of SIH are ruptured meningeal diverticula, ventral dural tears and CSF‐venous fistulas. SIH is associated with connective tissue disorders, and cases of SIH onset after trivial trauma have been reported. As SIH is often underdiagnosed, the aim of this study is to identify possible new risk factors of SIH onset in a case series of SIH patients.

Materials and methods

We retrospectively reviewed the medical records of 36 patients diagnosed with SIH. We reviewed and identified potential factors that led to or presented at headache onset in SIH patients.

Results

We identified 4/36 (11%) patients that had a close temporal relationship between the onset of SIH symptoms and airplane travel. In all four patients, the clinical and imaging features confirmed the diagnosis of SIH.

Conclusion

This is the first report of a case series of four patients with SIH that could be related to airplane travel. Describing four cases (11%) is not proof but should alert us to a possible causal relationship, which calls for further research. We suggest that when taking medical history, thorough details about the patient's activities, such as headache onset, should be documented because of their importance in correctly diagnosing SIH, which is a debilitating, yet treatable, disease.