Spontaneous intracranial hypotension: searching for the CSF leak

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.

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

BACKGROUND AND PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

"Empty Cyst Sign" Appearance of CSF-Venous Fistula on Digital Spinal Myelography

Cerebrospinal fluid venous fistulas (CSF-VFs) are an uncommon, yet increasingly recognized, cause of spontaneous intracranial hypotension.1-5 The workup involves magnetic resonance imaging (MRI) of the brain with and without contrast and MRI of the neuroaxis without contrast before dynamic myelography, either computed tomography or digital subtraction.6 The present case of an older woman with symptomatic intracranial hypotension is notable for the specific appearance of CSF-VFs on digital spinal myelography (Video 1). Among her numerous perineural cysts, it was the "disappearing" or "empty" cyst from which the fistula originated. The diagnosis was made using a second lateral fluoroscopy view, not typically used in digital spinal myelography, which demonstrated emptying of contrast from the T6 perineural cyst into the segmental vein at this level, or the "empty cyst sign." The patient then underwent transvenous onyx embolization with resolution of her orthostatic headaches and improvement of contrast-enhanced MRI of the brain with the Bern score decreasing from 7 to 0 at 3 months of follow-up.7 Because transvenous embolization of CSF-VFs is a relatively new procedure, the long-term outcomes of the procedure are not yet known.

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

RATIONALE

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

PATIENT CONCERNS

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

DIAGNOSIS

The final diagnose was SIH related headache with CCA.

INTERVENTION

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

OUTCOME

Favorable outcome was observed.

LESSONS

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

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

BACKGROUND AND PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Non-invasive biomarkers for spontaneous intracranial hypotension (SIH) through phase-contrast MRI

BACKGROUND AND OBJECTIVE

Spontaneous intracranial hypotension (SIH) is an underdiagnosed disease. To depict the accurate diagnosis can be demanding; especially the detection of CSF-venous fistulas poses many challenges. Potential dynamic biomarkers have been identified through non-invasive phase-contrast MRI in a limited subset of SIH patients with evidence of spinal longitudinal extradural collection. This study aimed to explore these biomarkers related to spinal cord motion and CSF velocities in a broader SIH cohort.

METHODS

A retrospective, monocentric pooled-data analysis was conducted of patients suspected to suffer from SIH who underwent phase-contrast MRI for spinal cord and CSF velocity measurements at segment C2/C3 referred to a tertiary center between February 2022 and June 2023. Velocity ranges (mm/s), total displacement (mm), and further derivatives were assessed and compared to data from the database of 70 healthy controls.

RESULTS

In 117 patients, a leak was located (54% ventral leak, 20% lateral leak, 20% CSF-venous fistulas, 6% sacral leaks). SIH patients showed larger spinal cord and CSF velocities than healthy controls: e.g., velocity range 7.6 ± 3 mm/s vs. 5.6 ± 1.4 mm/s, 56 ± 21 mm/s vs. 42 ± 10 mm/s, p < 0.001, respectively. Patients with lateral leaks and CSF-venous fistulas exhibited an exceptionally heightened level of spinal cord motion (e.g., velocity range 8.4 ± 3.3 mm/s; 8.2 ± 3.1 mm/s vs. 5.6 ± 1.4 mm/s, p < 0.001, respectively).

CONCLUSION

Phase-contrast MRI might become a valuable tool for SIH diagnosis, especially in patients with CSF-venous fistulas without evidence of spinal extradural fluid collection.

Cranial and Spinal Cerebrospinal Fluid Leaks: Foundations of Identification and Management

Cerebrospinal fluid (CSF) leaks may occur at the skull base or along the spinal column and can cause a variety of debilitating neurological symptoms for patients. Recognizing the potential presence of a CSF leak and then identifying its source are necessary for accurate diagnosis and definitive treatment. A standardized workflow can be followed for successful leak localization, which often requires several diagnostic studies, and for definitive leak treatment, which can range from minimally invasive, needle-based approaches to a variety of surgical corrections. This review paper provides an overview of epidemiology, pathophysiology, and diagnostic workup for CSF leaks and introduces available treatment options. An illustrative case of a skull base CSF leak demonstrating diagnosis and surgical correction is provided.

Clinical and imaging outcomes of 100 patients with cerebrospinal fluid-venous fistulas treated by transvenous embolization

BACKGROUND

Cerebrospinal fluid-venous fistulas (CSFVF) are a common cause of spontaneous intracranial hypotension (SIH). Transvenous embolization has emerged as a reliable treatment option. We review the clinical presentation, imaging, and clinical outcomes of 100 consecutive CSFVF patients who underwent embolization over 2 years.

METHODS

Baseline clinical characteristics, imaging findings (including Bern SIH score), technical outcomes, and long-term imaging and clinical outcomes were collected. All patients had at least 3 months of clinical follow-up and had baseline MRI. 99/100 patients underwent follow-up imaging at ≥3 months post-treatment.

RESULTS

100 patients were included. Mean imaging and clinical follow-up duration was 8.3±7.7 months and 15.0±6.8 months, respectively. The mean duration of symptoms before embolization was 40.9±52 months. Mean baseline Bern SIH score was 5.9±3.3. The most common baseline symptoms were headache (96 patients), tinnitus (55 patients), and cognitive dysfunction (44 patients). Technical success rate was 100%. Mean post-treatment Bern SIH score was 0.9±1.6 (P<0.0001). Following treatment, 95% of patients reported significant improvement or resolution in symptoms (58 patients reporting resolution and 37 reporting improvement). 5 patients reported no improvement. There were no major procedural or periprocedural complications. 10 patients had minor procedural complications that did not result in any change in management (Onyx emboli, venous perforation). 19 patients had rebound intracranial hypertension requiring acetazolamide therapy. 7 patients had recurrent fistula at the initially treated level.

CONCLUSIONS

Transvenous embolization of CSFVF in SIH patients is safe and effective with a 95% treatment response, significant improvement in imaging outcomes, and a very low rate of complications.

A Low-Volume Epidural Blood Patch for the Treatment of Spontaneous Intracranial Hypotension: A Case Report

Spontaneous intracranial hypotension (SIH) is a rare neurological syndrome. We report the case of a 47-year-old woman with acute, severe orthostatic headache after surgery, chemotherapy, and radiotherapy for breast cancer. The brain and spine magnetic resonance imaging showed signs of intracranial hypotension. We describe the results of a non-targeted epidural blood patch with 10 mL of the patient's blood administered after unsuccessful conservative treatment. After the procedure, the patient reported gradual headache relief. This effect persisted over one year. The case shows that a single non-targeted low-volume epidural blood patch can be an effective treatment option for a patient with SIH when conservative treatment fails.

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.

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

Background and Objectives

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

Methods

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

Results

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

Discussion

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

Pseudohypoxic brain swelling following elective lumbar laminectomy: A rare case report and review of literature

Pseudohypoxic brain swelling, also known as postoperative intracranial hypotension-associated venous congestion, is an intriguing complication following routine neurosurgical interventions. We report a case of a 73-year-old female patient who exhibited this rare complication following an elective L4-L5 laminectomy, without evidence of intraoperative cerebrospinal fluid leakage. Initially presenting with clinical features suggestive of anoxic/hypoxic brain injury, the case deviated from typical pseudohypoxic ischemic venous hypertension (PIHV) patterns, leading to a challenging diagnostic process. The patient's remarkable recovery, contrary to the initial grim prognosis, emphasizes the critical need for considering PIHV in differential diagnoses when postoperative symptoms mimic anoxic/hypoxic brain injuries. This case contributes to the evolving understanding of PIHV, particularly in scenarios lacking conventional risk factors like cerebral spinal fluid (CSF) leakage, and underscores the importance of comprehensive postoperative surveillance and management. It also highlights the imperative for continued research into the pathophysiology and treatment strategies of PIHV to enhance patient outcomes in complex surgical contexts.

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.

Myelography Using Energy-Integrating Detector CT Versus Photon-Counting Detector CT for Detection of CSF-Venous Fistulas in Patients With Spontaneous Intracranial Hypotension

BACKGROUND. CSF-venous fistulas (CVFs), which are an increasingly recognized cause of spontaneous intracranial hypotension (SIH), are often diminutive in size and exceedingly difficult to detect by conventional imaging. OBJECTIVE. This purpose of this study was to compare energy-integrating detector (EID) CT myelography and photon-counting detector (PCD) CT myelography in terms of image quality and diagnostic performance for detecting CVFs in patients with SIH. METHODS. This retrospective study included 38 patients (15 men and 23 women; mean age, 55 ± 10 [SD] years) with SIH who underwent both clinically indicated EID CT myelography (slice thickness, 0.625 mm) and PCD CT myelography (slice thickness, 0.2 mm; performed in ultrahigh-resolution mode) to assess for CSF leak. Three blinded radiologists reviewed examinations in random order, assessing image noise, discernibility of spinal nerve root sleeves, and overall image quality (each assessed using a scale of 0-100, with 100 denoting highest quality) and recording locations of the CVFs. Definite CVFs were defined as CVFs described in CT myelography reports using unequivocal language and having an attenuation value greater than 70 HU. RESULTS. For all readers, PCD CT myelography, in comparison with EID CT myelography, showed higher mean image noise (reader 1: 69.9 ± 18.5 [SD] vs 37.6 ± 15.2; reader 2: 59.5 ± 8.7 vs 49.3 ± 12.7; and reader 3: 57.6 ± 13.2 vs 42.1 ± 16.6), higher mean nerve root sleeve discernibility (reader 1: 81.6 ± 21.7 [SD] vs 30.4 ± 13.6; reader 2: 83.6 ± 10 vs 70.1 ± 18.9; and reader 3: 59.6 ± 13.5 vs 50.5 ± 14.4), and higher mean overall image quality (reader 1: 83.2 ± 20.0 [SD] vs 38.1 ± 13.5; reader 2: 80.1 ± 10.1 vs 72.4 ± 19.8; and reader 3: 57.8 ± 11.2 vs 51.9 ± 13.6) (all p < .05). Eleven patients had a definite CVF. Sensitivity and specificity of EID CT myelography and PCD CT myelography for the detection of definite CVF were 45% and 96% versus 64% and 85%, respectively, for reader 1; 36% and 100% versus 55% and 96%, respectively, for reader 2; and 57% and 100% versus 55% and 93%, respectively, for reader 3. The sensitivity was significantly higher for PCD CT myelography than for EID CT myelography for reader 1 and reader 2 (both p < .05) and was not significantly different between the two techniques for reader 3 (p = .45); for all three readers, specificity was not significantly different between the two modalities (all p > .05). CONCLUSION. In comparison with EID CT myelography, PCD CT myelography yielded significantly improved image quality with significantly higher sensitivity for CVFs (for two of three readers), without significant loss of specificity. CLINICAL IMPACT. The findings support a potential role for PCD CT myelography in facilitating earlier diagnosis and targeted treatment of SIH, avoiding high morbidity during potentially prolonged diagnostic workups.

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

BACKGROUND

The diagnosis of spontaneous or post-traumatic intracranial hypotension (IH) mainly relies on clinical features and neuro-imaging. However, the results of brain and spine magnetic resonance imaging are not always contributive. There is an interest for other non-invasive procedures, able to confirm or refute the diagnosis. The use of oto-acoustic emissions (OAE) was previously reported on isolated cases of IH associated with endolymphatic hydrops (ELH). The aim of this study was to assess the real-life utilization of this electrophysiological method in a larger population of suspected IH.

METHODS

A retro-prospective cohort study was conducted from November 2013 to July 2022 in patients with a suspected or doubtful diagnosis of IH. They were assessed for ELH by recording bilateral distortion product of oto-acoustic emissions (DPOAE) in sitting then in supine position.

RESULTS

Among the 32 patients assessed, the diagnostic of IH was confirmed in 18 patients. An ELH was shown in 15 of them (83%), but also in seven other patients. They had several differential diagnoses: chronic migraine, Chiari malformation, rebound intracranial hypertension and perilymph fistula.

CONCLUSIONS

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

Spinal Anterior Dural Dissection: Moving From Differential to Unifying Diagnosis

BACKGROUND AND OBJECTIVES

Cerebrospinal fluid (CSF) collections extending longitudinally at the anterior aspect of the spinal dura have been reported in association with various conditions and under multiple names. The aim of this study was to report cases associated with brachial amyotrophy (BA) and examine its relationship with other clinical variants.

METHODS

We conducted a retrospective cohort study including patients who presented with a motor deficit of the upper limbs and an anterior interdural CSF collection on spinal MRI. We performed a systematic review of the literature to include cases revealed by BA.

RESULTS

Seven patients presenting with BA and a confirmed dural dissection on spinal MRI were included. All patients were male with a slowly progressing history of asymmetrical and proximal motor deficit of the upper limbs. Chronic denervation affecting mostly C5 and C6 roots was found on electroneuromyography. Spinal MRI demonstrated an anterior CSF collection dissecting the interdural space and exerting a traction on cervical motor roots. Dynamic computed tomography myelogram localized the dural defect every time it was performed (4/7 cases), and surgical closure was possible for 3 patients, leading to resolution of the collection. Literature review yielded 18 other published cases of spinal dural dissections revealed by BA, including 4 in association with spontaneous intracranial hypotension and 4 others in association with superficial siderosis.

CONCLUSION

We propose a unifying diagnosis termed "spinal anterior dural dissection" (SADD) to encompass spinal dural CSF collections revealed by BA (SADD-BA), spontaneous intracranial hypotension (SADD-SIH), or superficial siderosis (SADD-SS).

CT-guided percutaneous cyanoacrylate injection targeting the spinal cerebrospinal fluid leak: a potential therapeutic option for spontaneous intracranial hypotension

BACKGROUND

We report the first case series of spontaneous intracranial hypotension (SIH) patients who underwent CT-guided percutaneous cyanoacrylate injection targeting the cerebrospinal fluid (CSF) leak.

METHODS

A retrospective analysis was performed for all consecutive cases of SIH patients with CSF leak confirmed on CT myelography, treated by CT-guided percutaneous cyanoacrylate injection at our institution from 2016 to 2022. On pretreatment brain and spine MRIs, we analyzed signs of SIH according to the Bern score, and dichotomized cases into positive/negative for spinal longitudinal extradural CSF collection (SLEC-P or SLEC-N). The leaks detected on CT myelography were classified into three types according to Schievink et al. We collected the Headache Impact Test 6 (HIT-6) scores throughout a 6-month follow-up, with a brain CT scan at each visit.

RESULTS

11 patients were included (mean age 48.4 years, six men). Five SLEC-P type 1, three SLEC-P type 2, and three SLEC-N type 3 leaks were identified. All patients had significant signs of SIH on pretreatment brain MRI (mean Bern score 7.8±1.1). Six patients underwent a foraminal puncture, and five patients had a cervical epidural approach. Two patients experienced mild and transient locoregional pain after cervical epidural injection. Mean HIT-6 score at baseline was 66.8±3.2 and at the 6-month follow-up was 38±3.6 (P<0.001). All patients achieved improvement in their symptoms, with 82% of them (9/11) having complete resolution of headaches and SIH findings on CT scans at 6 months. No clinical worsening or recurrence was observed.

CONCLUSIONS

CT-guided percutaneous cyanoacrylate injection may be a potential therapeutic option for the different types of CSF leak causing SIH.

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

RATIONALE

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

PATIENT CONCERN

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

DIAGNOSIS

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

INTERVENTIONS

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

OUTCOMES

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

LESSONS

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

Acquired tonsillar herniation related to spontaneous intracranial hypotension: case reports

Background

Acquired prolapse of the cerebellar tonsils in spontaneous intracranial hypotension (SIH) patients is rare. This study aims to evaluate neuroimaging changes of acquired prolapse of the cerebellar tonsils below the foramen magnum in SIH patients due to spontaneous spinal cerebrospinal fluid leakage, which was treated by targeted epidural blood patches (EBP).

Methods

We retrospectively reviewed clinical and neuroimaging characteristics of 5 cases of SIH with acquired prolapse of the cerebellar tonsils that received targeted EBP in our institution from January 2013 to December 2016.

Results

Of these SIH patients, all of them suffered from an orthostatic headache. Initial cranial MRI demonstrated descent of the cerebellar tonsils ≥5 mm. Intrathecal gadolinium-enhanced spinal MR myelography and/or spinal MR hydrography were performed to evaluate the level of spinal cerebrospinal fluid leakage. Symptoms were alleviated in all 5 patients after two (n = 4), or three (n = 1) targeted EBP during hospitalization. Follow-up cranial MRI revealed that the descent of cerebellar tonsils was reversed after EBP treatment.

Conclusion

Acquired tonsillar herniation can occur in patients with SIH and spinal cerebrospinal fluid leakage. Symptoms of these patients may be resolved and radiologic findings may be reversed after EBP treatment.

[Spinal Presentation of Spontaneous Intracranial Hypotension]

Spontaneous intracranial hypotension (SIH), which generally presents as orthostatic headache, is increasingly being identified due to improved imaging technologies and heightened awareness. Many prior studies have reported the characteristic brain MRI findings of SIH. However, recently, focus has shifted to spinal MRI, as SIH is believed to be caused by leakage of cerebrospinal fluid from the spinal dural sac. Advanced techniques such as ultrafast CT myelography and digital subtraction myelography have emerged as useful technique to identify the site of cerebrospinal fluid leakage. In this review, we discuss the diagnosis, spinal MRI findings, imaging techniques, and treatment of SIH.

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

BACKGROUND AND OBJECTIVES

To systematically describe pertinent, intraoperative anatomic findings encountered when approaching spinal cerebrospinal fluid (CSF) leaks and CSF-venous fistulas in spontaneous intracranial hypotension (SIH).

METHODS

In a retrospective study, we included surgically treated patients suffering from SIH at our institution from April 2018 to March 2022. Anatomic, intraoperative data were extracted from operative notes and supplemented with data from surgical videos and images. Prominent anatomic features were compared among different types of CSF leaks.

RESULTS

The study cohort consists of 120 patients with a mean age of 45.2 years. We found four distinct patterns of spinal membranes specifically associated with different types of CSF leaks: (i) thick, dorsal membranes, which were hypervascular and may mimic the dura (pseudodura); (ii) thin, lateral membranes encapsulating a ventral epidural CSF compartment (confining the spinal longitudinal extradural CSF collection); (iii) ventral membranes constituting a transdural funnel-like CSF channel; and (iv) lateral membranes forming spinal cysts/meningeal diverticulae associated with lateral CSF leaks. The latter three types resemble a layer of arachnoid herniated through the dural defect.

CONCLUSION

We describe four distinct spinal (neo-)membranes in association with spinal CSF leaks. Formation of these membranes, or emergence by herniation of arachnoid through a dural defect, constitutes a specific pathoanatomic feature of patients with SIH and CSF leaks. Recognition of these membranes is of paramount importance for diagnosis and treatment of patients with spinal CSF leaks.

A technique to localize posteriorly located spinal dural leaks associated with spontaneous intracranial hypotension: Dorsal-decubitus dynamic CT myelography

BACKGROUND

Precise localization and understanding of the origin of cerebrospinal fluid (CSF) leak is crucial to allow targeted treatment. We report the technical feasibility and utility of dorsal-decubitus dynamic computed tomography (DDDCT) myelography to localize posteriorly located dural defects in patients with suspicion of posterolateral dural tears.

METHODS

This study reports a series of four consecutive patients with posteriorly located SLEC and suspicion of posterolateral CSF leak who received DDDCT to localize the site of the leak. Patients were collected between October 2022 and October 2023. The technique of DDDCT and its efficacy to detect the site of CSF leak are reported.

RESULTS

In all four patients (three females, one male, mean age 39 years), DDDCT myelography was technically successful and precisely demonstrated the site of the CSF leak. In one patient with both anterior and posterior SLEC, DDDCT allowed to exclude the presence of a posteriorly located leak, while a subsequent ventral decubitus dynamic CT myelography localized the leak. Leak sites were all thoracic, except for one that was cervical. Information obtained from the DDDCT myelography was considered useful to target the treatment of the leak.

CONCLUSIONS

Based on our experience, DDDCT provided sufficient spatial and temporal resolution to pinpoint fast CSF leaks and it may be considered to localize posterolateral dural defects.

Efficacy of transvenous embolization of CSF-venous fistula in spontaneous intracranial hypotension: Case-series

BACKGROUND

Spontaneous intracranial hypotension is a debilitating neurological condition which can be caused by a cerebrospinal fluid-venous fistula. Transvenous embolization is a promising technique to provide minimally invasive yet durable treatment.

METHODS

A retrospective single-center case series was performed on all patients who underwent transvenous embolization of a cerebrospinal fluid (CSF)-venous fistula. Clinical and radiographic parameters, including Bern score, were reported preoperatively and at 3-month follow-up.

RESULTS

Six patients underwent embolization of a CSF-venous fistula. All fistulae were located in the thoracic spine and technical success was achieved in all cases. Three patients had symptom resolution, two had significant improvement, and one had stable symptoms on follow-up. The mean Bern score was 6.83 (SD = 1.47) preoperatively and 1.83 (SD = 1.64) postoperatively with a mean improvement in Bern score of 5.0 (SD = 1.9, p = 0.0013).

CONCLUSIONS

CSF-venous fistulas are an increasingly recognized clinical entity which may be treated with transvenous embolization. This case series serves to further validate this technique and suggests it can be performed with similar outcomes in lower volume centers.

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

PURPOSE

While there is thought to be an association between spinal nerve root diverticula (NRD) and spontaneous intracranial hypotension (SIH) without a spinal longitudinal epidural collection (SLEC), it remains unclear what the overall prevalence of SLEC-negative SIH is in patients with NRD on MRI.

METHODS

Spine MRI imaging reports from our single institution were electronically screened for instances of NRD over a 9-year period (2016-2023). From these cases, patients with brain MRIs consistent with SIH were also identified. Subsequently, the overall proportion of SLEC-negative SIH was determined as a function of total cases with NRD based on spinal level.

RESULTS

In total, 83,843 patients with spinal MRIs were screened which identified 4174 (4.97%) with NRD. From these, there were 1203 cervical, 622 thoracic, and 2979 lumbosacral spine MRIs. In total, 16 patients (0.38%; Standard Error [SE]: 0.48%-0.28%) had a brain MRI compatible with SLEC-negative SIH and met ICHD-3 criteria. Patients with cervical NRD had SIH in 2 cases (0.16%; SE: 0.27%-0.05%). SLEC-negative SIH was present in 11 patients with lumbosacral NRD (0.34%; SE: 0.44%-0.24%). In patients with diverticula in the thoracic spine, 14 (2.3%; SE: 2.8%-1.8%) had SLEC-negative SIH. SLEC-negative SIH was significantly more prevalent in patients with thoracic diverticula compared to those with cervical (p<.0001) or lumbosacral NRD (p<.0001).

CONCLUSION

In patients with spinal NRD, concurrent SLEC-negative SIH is present in approximately 0.38% of patients, suggesting that in the vast majority of cases, they are an incidental finding. However, SIH is present in approximately 2.3% of patients with thoracic NRD and may be more specific for leak localization.

Sacral Dural Tears as a Cause of Spontaneous Intracranial Hypotension

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Diagnosis and surgical therapy of spontaneous intracranial hypotension

Spontaneous intracranial hypotension (SIH) is a serious medical condition caused by loss of cerebrospinal fluid at the level of the spine, which, when not treated, may cause substantial long-term disability and increase morbidity. The following video summarizes the necessary steps for successful diagnosis and treatment of SIH, starting with a brain and spine magnetic resonance imaging, followed by dynamic myelography. Because an epidural bloodpatch did not provide a lasting relief, the patient underwent surgery which demonstrated a ventral dural slit caused by an osteodiscogenic microspur. In the 1-month follow up, the patient was symptom free. This video is meant to raise awareness of SIH among clinicians in order to increase general sensitivity for this diagnosis.

Likelihood of Discovering a CSF Leak Based on Intracranial MRI Findings in Patients without a Spinal Longitudinal Extradural Collection: A New Probabilistic Scoring System

BACKGROUND AND PURPOSE

The likelihood of discovering a CSF leak can be determined by assessing intracranial abnormalities. However, the Dobrocky scoring system, which is used to determine this likelihood, did not incorporate patients with CSF-venous fistulas. This study sought to create a new probabilistic scoring system applicable to patients without a spinal longitudinal extradural collection.

MATERIALS AND METHODS

A retrospective review was completed of patients with suspected spontaneous intracranial hypotension who underwent brain MR imaging followed by digital subtraction myelography with same-day CT myelography. Patients with and without leaks found on digital subtraction myelography were included. MRIs were assessed for numerous reported stigmata of spontaneous intracranial hypotension and were compared between cohorts.

RESULTS

One hundred seventy-four patients were included; 113 (64.9%) were women (average age, 52.0 [SD, 14.3] years). A CSF leak was found in 98 (56.3%) patients, nearly all of which (93.9%) were CSF-venous fistulas. Diffuse dural enhancement, internal auditory canals dural enhancement, non-Chiari cerebellar descent, pituitary engorgement, brain sag, dural venous sinus engorgement, and decreased suprasellar cistern size were associated with a CSF leak. A probabilistic scoring system was made in which a single point value was assigned to each of those findings: 0-2 considered low probability and ≥3 considered intermediate-to-high probability of a CSF leak.

CONCLUSIONS

This study offers a new probabilistic scoring system for evaluating the likelihood of discovering a CSF leak on the basis of intracranial MR imaging findings, though the new system is not superior to that of the Dobrocky method for predicting the presence of CSF leaks.

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.

Analysis of 3 Surgical Approaches for the Treatment of Cerebrospinal Fluid Otorrhea: A Case Series Report

Background: This case series report aimed to present three surgical approaches used for the treatment of cerebrospinal fluid (CSF) otorrhea, providing less invasive surgical options for managing this condition. Methods: Clinical data of 26 patients with CSF otorrhea, who underwent treatment using three surgical methods between June 2012 and June 2022, were retrospectively analyzed. The study collected information on patients' basic demographic characteristics, chief complaints, location of the defect, results of otorrhea endoscopic examination, findings from skull base thin-slice computed tomography (CT) examination, and causes of CSF otorrhea. Postoperative outcomes of CSF otorrhea were followed up. Results: Among the 26 cases of CSF otorrhea, there were 13 (50%) males and 13 (50%) females who underwent treatment using the three surgical methods. The etiology of CSF otorrhea included 10 (38%) cases of spontaneous CSF otorrhea, including 2 (8%) cases of congenital inner ear deformity and 8 (31%) cases without obvious inducement. Additionally, there were 5 (19%) cases of trauma, 6 (23%) cases of cholesteatoma complications, 3 (12%) cases of postoperative complications of brain tumor, 1 (4%) case of radiotherapy, and 1 (4%) case of a malignant tumor. A total of 12 (46%) cases of CSF otorrhea were treated by local repair of the defect. Furthermore, 3 (12%) cases underwent local repair of the defect combined with sealing of the tympanic sinus entrance, while 11 (42%) cases underwent local repair of the defect combined with sealing of the eustachian tube and the external auditory canal. No recurrence of CSF otorrhea was observed during the 6-month to 10-year follow-up period after surgery. Conclusion: The three methods for CSF otorrhea, including local defect repair, local defect repair combined with sealing of the tympanic sinus entrance, and sealing of the eustachian tube and the external auditory canal, demonstrated successful outcomes in appropriately selected patients.

Spontaneous Intracranial Hypotension: An Uncommon Cause of Postural Vestibulocochlear Symptoms

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

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.

[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.

A False Pituitary Tumor

A false pituitary tumor describes pituitary enlargement due to intracranial hypotension. Reported previously primarily in the neurological literature, we present this case referred to endocrinology for evaluation of a pituitary mass. A 24-year-old male was referred to endocrinology for evaluation of pituitary enlargement without a hypo-enhancing lesion on magnetic resonance imaging (MRI). The main symptom reported was headache that was worse in the standing position and in the afternoon. He had no symptoms or signs of pituitary mass-effect, or hormone excess or deficiencies. Past medical history was relevant for a history of nerve schwannoma status post resection with subsequent spinal fusion. Biochemical evaluation of pituitary hormones was normal. Upon review of his pituitary MRI, other abnormalities seen were suggestive of intracranial hypotension. Based on his history and imaging findings, he was diagnosed with intracranial hypotension causing a "false pituitary tumor" rather than pituitary enlargement or abnormality. Further evaluation revealed multiple spinal leaks that were patched. His symptoms subsided within a few days of repair. Endocrinologists should be aware of the possible misdiagnosis of a pituitary mass due to intracranial hypotension.

Intraoperative Visualization of Flow in Direct Cerebrospinal Fluid-Venous Fistulas Using Intrathecal Fluorescein

BACKGROUND

Cerebrospinal fluid-venous fistulas (CVFs) are a rare cause of spontaneous intracranial hypotension. Intraoperatively, CVFs are not readily identifiable and difficult to differentiate from normal veins.

OBJECTIVE

To assess the utility of intrathecal fluorescein injection intraoperatively to visualize and identify the CVF.

METHODS

We report a case series of patients treated surgically for a CVF. After surgical exposure, we injected intrathecal fluorescein (5-10 mg) through a lumbar catheter, which we placed immediately before surgery.

RESULTS

Four patients with spontaneous intracranial hypotension with a suspected CVF underwent surgical ligation with adjunctive intrathecal fluorescein application. Intraoperative fluorescein injection confirmed the presence of a CVF in 3 cases. In 2 cases, we observed rapid fluorescein filling of a single epidural vein constituting the CVF. Other epidural vessels did not fill with fluorescein. In 1 case, fluorescein helped to identify a residual CVF after previous incomplete embolization. In the fourth case, no CVF was found intraoperatively. By contrast, a meningeal nerve root diverticulum was visualized, wrapped, and clipped.

CONCLUSION

We demonstrate for the first time the direct intraoperative visualization of CVF using intrathecal fluorescein. CVF can be identified intraoperatively using fluorescein dye, which can be a valuable adjunct for the surgeon confronted with this disease.

Plasma neurodegeneration biomarker concentrations associate with glymphatic and meningeal lymphatic measures in neurological disorders

Clearance of neurotoxic brain proteins via cerebrospinal fluid (CSF) to blood has recently emerged to be crucial, and plasma biomarkers of neurodegeneration were newly introduced to predict neurological disease. This study examines in 106 individuals with neurological disorders associations between plasma biomarkers [40 and 42 amino acid-long amyloid-β (Aβ40 and Aβ42), total-tau, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL)] and magnetic resonance imaging measures of CSF-mediated clearance from brain via extra-vascular pathways (proxy of glymphatic function) and CSF-to-blood clearance variables from pharmacokinetic modeling (proxy of meningeal lymphatic egress). We also examine how biomarkers vary during daytime and associate with subjective sleep quality. Plasma concentrations of neurodegeneration markers associate with indices of glymphatic and meningeal lymphatic functions in individual- and disease-specific manners, vary during daytime, but are unaffected by sleep quality. The results suggest that plasma concentrations of neurodegeneration biomarkers associate with measures of glymphatic and meningeal lymphatic function.

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.

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.

68Ga-DOTA PET for Diagnosis of Spinal Cerebrospinal Fluid Leaks

Spontaneous intracranial hypotension due to spinal cerebrospinal fluid (CSF) leakage causes substantial disease burden. In many patients, the course is protracted and refractory to conservative treatment, requiring targeted therapy. We propose PET of the CSF space with 68Ga-DOTA as a state-of-the-art approach to radionuclide cisternography (RC) and validate its diagnostic value. Methods: This study is a retrospective analysis of patients with suspected intracranial hypotension due to spinal CSF leaks and who underwent whole-body PET/CT at 1, 3, and 5 h after intrathecal lumbar injection of 68Ga-DOTA. Two independent raters unaware of the clinical data analyzed all scans for direct and indirect RC signs of CSF leakage. Volume-of-interest analysis was performed to assess the biologic half-life of the tracer in the CSF space and the ratio of decay-corrected activity in the CSF space at 5 and 3 h (simplified marker of tracer clearance). Comprehensive stepwise neuroradiologic work-up served as a reference; additional validation was provided by surgical findings and follow-up. Results: Of 40 consecutive patients, 39 patients with a working diagnosis of intracranial hypotension due to a spinal CSF leak (spontaneous, n = 31; postintervention, n = 8) could be analyzed. A spinal CSF leak was verified by the neuroradiologic reference method in 18 of 39 patients. As the only direct and indirect diagnostic signs, extrathecal tracer accumulation at the cervicothoracic junction (67% sensitivity and 90% specificity) and lack of activity over the cerebral convexities (5 h; 94% sensitivity and 67% specificity) revealed a high diagnostic value for spinal CSF leaks. Their combination provided little improvement (71% sensitivity and 95% specificity). Additional quantitative analyses yielded no benefit (94% sensitivity and 53% specificity for biological half-life; 94% sensitivity and 58% specificity for the ratio of total radioactivity within the CSF space at 5 and 3 h). The location of direct signs (extrathecal tracer accumulation) did not correlate with verified sites of spinal CSF leakage. Conclusion: We propose CSF PET with 68Ga-DOTA as a novel, fast, and convenient approach to RC for verification but not localization of spinal CSF leaks with high sensitivity and specificity. CSF PET may fulfill an important gatekeeper function for stratifying patients toward escalation (ruling in) or deescalation (ruling out) of diagnostic and therapeutic measures. Further prospective studies are needed to validate the present results and determine the potential of the methods to reduce the burden to patients.

Progressive loss of hearing and balance in superficial siderosis due to occult spinal dural defects

PURPOSE

Superficial siderosis, a progressive, debilitating, neurological disease, often presents with bilateral impairment of auditory and vestibular function. We highlight that superficial siderosis is often due to a repairable spinal dural defect of the type that can also cause spontaneous intracranial hypotension.

METHODS

Retrospective chart review of five patients presenting with moderate to severe, progressive bilateral sensorineural hearing loss as well as vestibular loss. All patients had developed superficial siderosis from spinal dural defects: three after trauma, one after spinal surgery and one from a thoracic discogenic microspur.

RESULTS

The diagnosis was made late in all five patients; despite surgical repair in four, hearing and vestibular loss failed to improve.

CONCLUSIONS

In patients presenting with progressive bilateral sensorineural hearing loss, superficial siderosis should be considered as a possible cause. If these patients also have bilateral vestibular loss, cerebellar impairment and anosmia, then the diagnosis is likely and the inevitable disease progress might be halted by finding and repairing the spinal dural defect.

Minimally invasive surgery for spinal cerebrospinal fluid leaks in spontaneous intracranial hypotension

OBJECTIVE

Spinal CSF leaks cause spontaneous intracranial hypotension (SIH). Surgical closure of spinal CSF leaks is the treatment of choice for persisting leaks. Surgical approaches vary, and there are no studies in which minimally invasive techniques were used. In this study, the authors aimed to detail the safety and feasibility of minimally invasive microsurgical sealing of spinal CSF leaks using nonexpandable tubular retractors.

METHODS

Consecutive patients with SIH and a confirmed spinal CSF leak treated at a single institution between April 2019 and December 2020 were included in the study. Surgery was performed via a dorsal 2.5-cm skin incision using nonexpandable tubular retractors and a tailored interlaminar fenestration and, if needed, a transdural approach. The primary outcome was successful sealing of the dura, and the secondary outcome was the occurrence of complications.

RESULTS

Fifty-eight patients, 65.5% of whom were female (median age 46 years [IQR 36-55 years]), with 38 ventral leaks, 17 lateral leaks, and 2 CSF venous fistulas were included. In 56 (96.6%) patients, the leak could be closed, and in 2 (3.4%) patients the leak was missed because of misinterpretation of the imaging studies. One of these patients underwent successful reoperation, and the other patient decided to undergo surgery at another institution. Two other patients had to undergo reoperation because of insufficient closure and a persisting leak. The rate of permanent neurological deficit was 1.7%, the revision rate for a persisting or recurring leak was 3.4%, and the overall revision rate was 10.3%. The rate of successful sealing during the primary closure attempt was 96.6% and 3.4% patients needed a secondary attempt. Clinical short-term outcome at discharge was unchanged in 14 patients and improved in 25 patients, and 19 patients had signs of rebound intracranial hypertension.

CONCLUSIONS

Minimally invasive surgery with tubular retractors and a tailored interlaminar fenestration and, if needed, a transdural approach is safe and effective for the treatment of spinal CSF leaks. The authors suggest performing a minimally invasive closure of spinal CSF leaks in specialized centers.

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.