Skull Base Cerebrospinal Fluid Research Articles

Endoscopic Repair of Anterior Skull Base Cerebrospinal Fluid Leaks is Successful in Frail Patients.

Surgical frailty estimates a patient's ability to withstand the physiologic stress of an intervention. There is limited data regarding the impact of frailty on endoscopic cerebrospinal fluid (CSF) leak repair. Patients undergoing CSF leak repair at two tertiary academic skull base programs were retrospectively reviewed. Demographic, treatment, and postoperative outcomes data were recorded. Frailty was calculated using validated indices, including the American Society of Anesthesiologists (ASA) classification, Charlson Comorbidity Index (CCI), and the Modified 5-Item Frailty Index (mFI-5). Outcomes included 30-day medical and surgical complications and readmission. A total of 185 patients were included with 128 (69.2%) female patients and average age of 54 ± 14 years. The average body mass index was 34.6 ± 8.5. The most common identified etiology was idiopathic intracranial hypertension (IIH) in 64 patients (34.6%). A total of 125 patients (68%) underwent perioperative lumbar drain placement (primarily to measure intracranial pressures and diagnose IIH). Most patients were ASA class 3 (48.6%) with mean CCI 2.14 ± 2.23 and mFI-5 0.97 ± 0.90. Three patients had postoperative CSF leaks, with an overall repair success rate of 98.4%. There was no association between increased frailty and 30-day medical outcomes, surgical outcomes, or readmission (all p > 0.05). Endoscopic CSF leak repair in a frail population, including lumbar drain placement and bed rest, was not associated with an increased rate of complications. Previous data suggests increased complications in open craniotomy procedures in patients with significant comorbidities. This study suggests that the endoscopic approach to CSF leak repair is well tolerated in the frail population. IV Laryngoscope, 134:2713-2717, 2024.

Short Postoperative Length of Stay After Lateral Cerebrospinal Fluid Leak Repair.

To characterize the short-term outcomes of patients undergoing surgical repair of lateral skull base cerebrospinal fluid (CSF) leaks followed by a shortened length of stay (LOS) protocol. Retrospective study. Tertiary medical center. Atotal of 156 adult patients from July 2016 to December 2022 who underwent repair of CSF leaks via transmastoid (TM), middle cranial fossa (MCF), or combined (TM/MCF) approaches were included. Data collected included: LOS, presentation to the emergency department (ED), need for readmission, major neurologic complications (stroke, seizure, and meningitis), and CSF leak recurrence. Approximately half of patients underwent a TM repair (49.4%), whereas the other half underwent either an MCF (3.8%) or combined TM/MCF repair (46.8%). No peri-/postoperative lumbar drains were used and only 2 (1.3%) patients were admitted to the intensive care unit after surgery. Mean LOS for the cohort was 1.1 ± 0.7 days and was longer for surgeries involving MCF (1.3 ± 0.6) compared to TM (0.8 ± 0.7). Ninety-two percent of TM cases were discharged within 24hours (32% on the same day) while for cases involving an MCF approach, 72.2% of patients were discharged within 24hours. Of the patients in the study, 6 (3.8%) presented to an ED for minor complications and no patient required readmission. Revision surgery was required for 3 (1.9%) patients for recurrent CSF leak. Our findings suggest that short LOS after surgical repair of lateral skull base defects in the treatment of CSF leak is safe and effective.

Hydroxyapatite Use in Repair of Lateral Skull Base CSF Leaks Via Transmastoid Approach: When Does It Work?

The objective of this study is to evaluate the efficacy and outcomes of using a transmastoid approach with hydroxyapatite cement to repair lateral skull base cerebrospinal fluid (CSF) leaks. Retrospective cohort study. Tertiary-level care hospital. Surgical patients 18 years or older between 2013 and 2022 with spontaneous CSF leak. Trans-mastoid approach for skull base repair using hydroxyapatite cement. Failure rate of repair; location and size of defect, patient demographic factors. Of the 60 total defects (55 patients, 5 bilateral repairs) that underwent CSF leak repair using hydroxyapatite cement, the success rate was 91.66% (55 successful repairs). The average defect size in unsuccessful repairs was 1.15 cm compared with 0.71 cm for successful repairs. In addition, 80% (4/5) of the failed repairs were in the tegmen tympani region. Higher failure rate was noted in women (3/5) and in former smokers (4/5). Average time to recurrent symptoms was 1.75 years in the failed repair cohort. Of the patients with failed repairs, 4/5 were prescribed acetazolamide before their second procedure with successful second repair. In addition, five patients experienced postoperative headaches, three (5.4%) of whom required placement of VP shunts to relieve increased intracranial pressure. Two patients (3.6%) had complications of either infection or hearing loss. Transmastoid approach utilizing hydroxyapatite is a successful approach for CSF leak repair, with a low complication and failure rate. Women, prior smoking history, and larger defects in the tegmen tympani region may need alternative materials or approach for repair. Long follow-up is warranted as recurrence of symptoms might be delayed. In cases of benign intracranial hypertension, adjuvant treatment with either acetazolamide or VP shunt placement may prevent failures.

Fluoroscopy-guided multiphase flat panel CT cisternography to diagnose complex skull base CSF leaks

Skull base cerebrospinal fluid (CSF) leaks can be challenging to diagnose. We describe a first technical report on a fluoroscopy-guided multiphase flat panel computed tomography cisternography to diagnose a CSF leak in a complex postoperative anterior cranial fossa. The entry point, pathway of leakage, and exit point were visualized in detail. The feasibility and technical details are described. This technique could be an additional asset in the diagnostic work up of complex CSF leaks, not only of the anterior cranial fossa, but also complex CSF leaks of the middle cranial fossa.

Meningitis Risk and Role of Prophylactic Antibiotics in Spontaneous Lateral Skull Base CSF Leaks.

To review the literature and our institutional experience regarding the risk of meningitis in patients with spontaneous lateral skull base cerebrospinal fluid (sCSF) leaks awaiting surgical repair, and the roles of antibiotic prophylaxis and pneumococcal vaccination, if known. A retrospective chart review and systematic review of the literature was undertaken to identify the incidence of meningitis in patients with sCSF leaks awaiting surgical repair. Adults managed surgically for sCSF leaks at an academic tertiary care center over a 10-year period were included. Data was collected on receipt of prophylactic antibiotics and/or pneumococcal vaccines during the timeframe between diagnosis and surgical repair. Institutional review identified 87 patients who underwent surgical repair of spontaneous leaks, with a 0% incidence of meningitis over a median duration of 2 months while awaiting surgery (mean 5.5 months, range 0.5-118 months). Eighty-eight percent of patients did not receive prophylactic antibiotics. No studies in the published literature demonstrated the impact of prophylactic antibiotics or pneumococcal vaccine on meningitis risk. There appears to be a low risk of meningitis among patients with lateral skull base sCSF leaks awaiting surgery for short durations (≤2 months), even in the absence of prophylactic antibiotics. There is a substantial gap in the published literature assessing the risk of meningitis and roles of antibiotics and vaccination in this patient population, indicating the need for large-scale study to conclusively elucidate the nature of this risk.

Dural sinus narrowing in patients with spontaneous anterior skull base cerebrospinal fluid leak.

Current evidence suggests a link between idiopathic intracranial hypertension (IIH) and spontaneous cerebrospinal fluid (sCSF) leak, as well as between IIH and dural venous sinus (DVS) narrowing. However, there are limited data linking DVS narrowing and sCSF leak. This study aims to determine the prevalence of DVS narrowing in patients with sCSF leak. A retrospective review of all patients with sCSF leak that presented to a tertiary academic center from 2008 to 2019. Preoperative imaging was independently reviewed by two neuroradiologists to evaluate for DVS narrowing. Available literature was used to estimate the prevalence of DVS narrowing in the general population to allow for comparison. Data were analyzed using Exact binomial test. Analysis of 25 patients with appropriate imaging revealed the majority were women (21/25, 84%) with a mean age of 51.89 years (SD 13.96). The majority of these patients were found to have narrowing of the DVS (20/25, 80%). In patient with sCSF leaks, there was a significantly higher proportion of patients with DVS narrowing compared with published literature examining this condition in the general population (80% vs. 40%, CI 0.59-0.93, p < .001). The prevalence of DVS narrowing in patients with sCSF leaks is substantial and likely greater than the general population. Moreover, there appears to be narrowing in most patients with sCSF leak. Preoperative radiological evaluation of the DVS using MR venography may be useful in patients with sCSF leaks as DVS stenosis may be an underdiagnosed etiology. Further study is needed to evaluate this. IV.

Spontaneous skull base cerebrospinal fluid leak during pregnancy: a case report and review of the literature

BackgroundIdiopathic intracranial hypertension can lead to dural defects and spontaneous leakage of cerebrospinal fluid (CSF) from the skull base. Skull base CSF leaks are rarely reported in pregnancy but pose unique challenges for obstetricians and anesthesiologists.Case presentationA 31-year-old G4P1021 at 14 weeks developed debilitating headaches and CSF rhinorrhea. Brain imaging revealed a bony defect of the sphenoid sinus with a meningoencephalocele and a partially empty sella, consistent with CSF leakage from a skull base defect. The patient was neurologically stable without signs of meningitis; thus, management was focused on symptomatic alleviation. A planned cesarean section was performed at 38 weeks under spinal anesthesia. The patient had spontaneous marked improvement of her symptoms postpartum.ConclusionPregnancy may exacerbate skull base CSF leaks, requiring careful management with a multidisciplinary team. Neuraxial anesthesia can safely be performed in pregnant individuals with spontaneous skull base CSF leakage, but further studies are needed to determine the safest mode of delivery in these patients.

Determining the Best First-line Modality for Identifying and Localizing Skull Base CSF Leaks

Background: Patients with skull base cerebrospinal fluid (CSF) leaks present with headaches, fluid in the ear(s), and/or rhinorrhea, which are vague symptoms. Beta-2-transferrin protein assays are the gold standard for identifying CSF leaks, but adequate samples cannot always be collected, and the results give no specific localizing information. Medical imaging, including Computed Tomography (CT), Magnetic Resonance (MR), and Nuclear Medicine (NM) cisternography can be utilized to identify and localize CSF leaks, but are imperfect tests. This study aims to determine the best imaging modality for identifying and localizing skull base CSF leaks by comparing CT, MR, and NM Cisternogram results to beta-2-transferrin assay and intraoperative visualization as criterion standards.&#x0D; Methods: In this ongoing study, patient cisternogram and pre-cisternogram imaging and results were acquired from the electronic medical record, radiology information system, and picture archiving and communication system. Inclusion criteria include age greater than 18, suspected skull base CSF leak, and CT, MR, and/or NM cisternogram performed. MR cisternogram procedure included intrathecal gadolinium and NM SPECT-CT cisternogram procedure included intrathecal Tc-99m Sulfur Colloid. These data will be analyzed for positive and negative predictive values, sensitivity, specificity, and ROC Curve comparing to beta-2-transferrin assay results and surgical findings.&#x0D; Results: From 2018-2022, 30 patients with suspected skull base CSF leaks were evaluated. In this limited preliminary data set, MR was more sensitive than CT, CT was more sensitive than NM, there were three false negatives, and there were no false positives. Performing two types of cisternogram increased the chance of identifying leaks. More data is needed to draw stronger conclusions in this ongoing study.&#x0D; Conclusion/Potential Impact: The initial data suggests that MR cisternogram with intrathecal gadolinium is superior to CT and SPECT-CT cisternogram for detecting skull base CSF leaks. Localizing skull base CSF leaks helps enable surgeons to perform less invasive corrective procedures.

Surgical Repair of Skull Base CSF Leaks after Cisternography Diagnosis: Analysis of Validity and Surgical Outcome and Impact on Future Treatment Strategies.

Skull base cerebrospinal fluid (CSF) leaks can lead to severe complications and require appropriate diagnosis and treatment. Cisternography is applied when exact localization via conventional imaging is not successful. The present study is aimed at identifying factors with potential impact on radiological results and surgical success. Cisternography followed by surgical repair due to skull base CSF leaks was performed in 63 cases between 2002 and 2020. The clinical and radiological findings were analyzed retrospectively. The etiology of CSF leaks was traumatic in 30.2%, spontaneous in 36.5%, and iatrogenic in 33.3%. The sensitivity of cisternography was 87.9%. Spontaneous CSF leaks tended to be diagnosed less frequently via cisternography and were significantly less frequently localized intraoperatively. The median postoperative follow-up period was 34 months. The primary surgical success rate was 79.4%, with a significantly higher success rate for lateral than for anterior skull base defects. Surgical failure tended to be lower in iatrogenic and higher in traumatic defects. Cisternography proved to be a highly sensitive method to localize skull base CSF leaks and can be recommended for advanced diagnostics. Iatrogenic leaks seemed to be more likely to have a favorable surgical outcome, whereas traumatic leaks tended to have a lower surgical success rate.

Endoscopic closure of the Eustachian tube orifice for refractory lateral skull base cerebrospinal fluid leak using autologous fat graft: illustrative case.

BACKGROUNDRhinorrhea due to lateral skull base cerebrospinal fluid (CSF) leaks can be a challenge to manage. Multiple strategies exist for treating CSF leaks in this region including direct repair, posterior Eustachian tube packing, and CSF diversion. Endonasal closure of the Eustachian tube has been reported using cerclage and mucosal flaps.OBSERVATIONSWe present the first reported case of endoscopic autologous fat packing of the Eustachian tube orifice to repair a CSF leak. In this case a 42-year-old woman who underwent middle fossa meningioma resection 20 years ago presented with refractory CSF rhinorrhea despite blind sac closure of the ear canal. This persisted after CSF diversion and only resolved after endoscopic endonasal Eustachian tube closure described herein.LESSONSThis technique is simple to perform with minimal risk of morbidity. Eustachian tube orifice fat packing may be particularly useful for patients with refractory CSF rhinorrhea with low CSF pressure.

Assessing the utility of intrathecal fluorescein in endoscopic repair of anterior skull base cerebrospinal fluid leaks.

Assessing the utility of intrathecal fluorescein in endoscopic repair of anterior skull base cerebrospinal fluid leaks.

Imaging of Acquired Skull Base Cerebrospinal Fluid Leaks.

Acquired skull base cerebrospinal fluid (CSF) leaks can result from trauma, tumors, iatrogenic causes, or may be spontaneous. Spontaneous skull base CSF leaks are likely a manifestation of underlying idiopathic intracranial hypertension. The initial assessment of rhinorrhea or otorrhea which is suspected to be due to an acquired skull base CSF leak requires integration of clinical assessment and biochemical confirmation of CSF. Imaging with high-resolution CT is performed to locate osseous defects, while high-resolution T2w MRI may detect CSF traversing the dura and bony skull base. When leaks are multiple or if samples of fluid cannot be obtained for testing, then recourse to invasive cisternography may be necessary.

351 Anterior Ethmoid Artery Septal Flap for Endoscopic Reconstruction of Frontal Sinus CSF Leak

Abstract Introduction Anterior skull base cerebrospinal fluid (CSF) leaks are managed successfully with endonasal surgery. Endoscopic closure of CSF leaks from posterior table of the frontal sinus remains challenging. Vascularized Hadad-Bassagasteguy flap (HBF) reconstruction of the skull base has increased CSF closure rates but does not extend to frontal sinus. We describe our technique using septal flap pedicled by anterior ethmoid artery (AEA) for repairing frontal defects. Method Retrospective review of cases of frontal CSF leak repair using the AEA flap reconstruction. Flap design: an anterior vertical septal mucosa incision at posterior border of the frontal sinusotomy is made and extended to nasal floor. Posterior vertical incision is made 1 cm posterior to the projection of the axilla of the middle turbinate on the septum and extended to nasal floor. A horizontal incision along the nasal floor joins the two incisions. The flap is raised and rotated into the frontal sinus over the posterior table reconstructed defect. Results Three patients identified. Two males, one female, aged 11, 33 and 56. Patient histories included recurrent bacterial meningitis following head trauma, recurrent sinusitis and fronto-ethmoidal osteoma, with intraoperative CSF leak and CSF rhinorrhea due to meningoencephalocele. The three posterior wall defects were successfully repaired endoscopically with multilayer reconstruction and the AEA septal flap. Conclusions The anterior ethmoid artery septal flap can be successfully utilised for frontal CSF leak repair. Flap is conveniently located for frontal sinus defects. When the septum is intact it provides an excellent final layer as part of multilayer reconstruction.

Special MRI Techniques to Suss out Spontaneous Cerebrospinal Fluid Leaks.

Anterior skull base cerebrospinal fluid (CSF) fistulas result from skull base osteodural defects, allowing subarachnoid space CSF to escape into pneumatized cavities such as the paranasal sinuses and nasal fossa. Precise localization, characterization, and effective treatment of CSF leaks is essential to prevent meningitis, treatment failure, or recurrence. Advances in magnetic resonance imaging have improved radiologists' ability to localize and characterize anterior skull base CSF fistulas. This article reviews new imaging techniques enabling diagnostic location of CSF fistulas, with an emphasis on magnetic resonance imaging-based techniques.

Prediction of Postoperative Risk of Raised Intracranial Pressure After Spontaneous Skull Base Cerebrospinal Fluid Leak Repair.

A relationship between idiopathic intracranial hypertension and spontaneous skull base cerebrospinal fluid (CSF) leaks has been proposed, by which CSF leak decreases intracranial pressure (ICP) and masks the symptoms and signs of elevated ICP. These patients are at risk of developing papilledema, symptoms of elevated ICP, or a recurrent CSF leak after CSF leak repair. The objective of this study was to assess whether radiographic signs of raised ICP on preoperative magnetic resonance or computed venography (MRI or CTV) are predictors of postoperative papilledema, recurrence of CSF leak, or need for CSF shunt surgery. We performed a retrospective review of systematically collected demographics, fundus examination, and presurgical brain MRI and magnetic resonance venography/computed tomography venography (MRV/CTV) in patients seen at 1 institution between 2013 and 2019 with spontaneous skull base CSF leak repair. Patients were divided into 2 groups depending on whether they developed papilledema, recurrent CSF leak, or required CSF shunting (Group 1) or not (Group 2). Fifty-seven patients were included, among whom 19 were in Group 1. There was no difference in demographic characteristics or clinical features between patients in Group 1 and Group 2. Controlling for other imaging features, bilateral transverse venous sinus stenosis (TVSS) on preoperative imaging increased the odds of being in Group 1 by 4.2 times (95% confidence interval [CI], 1.04-21.2, P = 0.04), optic nerve tortuosity decreased the odds of being in Group 1 by 8.3 times (95% CI: 1.4-74.6, P = 0.02). Imaging of the intracranial venous system with MRV or CTV is warranted before repair of spontaneous CSF leak, as bilateral TVSS is an independent risk factor for postoperative papilledema, CSF leak recurrence, or need for a CSF shunting procedure.

Should the Impact of Postural Change of Intracranial Pressure After Surgical Repair of Skull Base Cerebrospinal Fluid Leaks Be Considered? A Preliminary Survey.

Managing skull base cerebrospinal fluid (CSF) leaks is often challenging. Postoperative care, especially regarding postural restrictions and bedrest recommendations, is variable and continues to be based on empirical habits. An electronic survey was submitted to French experts in skull base surgery to evaluate current practice of postoperative postural recommendations in patients treated for skull base CSF leaks. Thirty-nine experts completed the survey. Postoperative recommendations were heterogenous. They depended on the size of defects: half of the surgeons did not recommend any constraints of posture for small defects; 84% recommended bed rest for large defects. The most preferred bed-rest modality was Fowler's position (20°-30° tilt). Standing/walking during short periods was allowed in up to 73%. From a physiological viewpoint, head elevation decreases ICP and thus limits the risk of recurrence of CSF leak. However, ICP can fall below 0 in the standing position, favouring pneumocephalus. These results confirmed that postural recommendations for patients surgically treated for skull base CSF leaks remain variable. Recommendations should take into consideration the postural change in ICP. Fowler's position may represent the best compromise between risk of recurrence of CSF leak and the risk of pneumocephalus in large CSF leaks.

Skull Base Csf- Leak Closure with Autologous Fibrin Sealant.

IntroductionThere are many fibrin-derived sealants used as topical haemostatic agents in many surgical procedures. Fibrin sealants are usually non-autologous derivatives or animal derivatives, with the exception of Vivostat®, an autologous fibrin sealant derived from patients own blood.Materials and MethodsWe present our experience on the use of Vivostat® in skull base closures in 20 patients operated at the Otorhinolaryngology Unit of the Hospital Ospedali Riuniti Villa Sofia - Cervello of Palermo. All postoperative patients were placed in an anti-trendeleburg position for 48 hours. After removal of the nasal swabs we did not find any rhinorrhea and we checked the tightness of the skull base defect with computed tomography.ResultsOn a total of the 20 patients (10 post-traumatic and 10 with iatrogenic leaks), 9 out of 10 post-traumatic cases had a leak in the border area between the anterior and posterior portion of the ethmoid, while 1 patient out of 10 post-traumatic cases had a leak at the level of the sella. In all 20 patients, we repaired skull base defects by fixing grafting materials with Vivostat®. We have not had any complications. Vivostat® is a useful product in skull base repair and safe for the patients.ConclusionVivostat® has been used as a sealant on body tissues with greater elasticity and more resistant allowing better and safer wound repair, especially in skull base surgery. In particular, its immediate polymerisation is very useful for an evaluation of the mechanical sealants in the closure of the skull base cerebrospinal fluid leak.

Atypical presentations of idiopathic intracranial hypertension.

Idiopathic intracranial hypertension (IIH) is a disorder of unknown etiology that results in isolated raised intracranial pressure. Classic symptoms and signs of IIH include headache, papilledema, diplopia from sixth nerve palsy and divergence insufficiency, and pulsatile tinnitus. Atypical presentations include: (1) highly asymmetric or even unilateral papilledema, and IIH without papilledema; (2) ocular motor disturbances from third nerve palsy, fourth nerve palsy, internuclear ophthalmoplegia, diffuse ophthalmoplegia, and skew deviation; (3) olfactory dysfunction; (4) trigeminal nerve dysfunction; (5) facial nerve dysfunction; (6) hearing loss and vestibular dysfunction; (7) lower cranial nerve dysfunction including deviated uvula, torticollis, and tongue weakness; (8) spontaneous skull base cerebrospinal fluid leak; and (9) seizures. Although atypical findings should raise a red flag and prompt further investigation for an alternative etiology, clinicians should be familiar with these unusual presentations.

CSF rhinorrhoea after endonasal intervention to the anterior skull base (CRANIAL): proposal for a prospective multicentre observational cohort study

Background The endonasal transsphenoidal approach (TSA) has emerged as the preferred approach in order to treat pituitary adenoma and related sellar pathologies. The recently adopted expanded endonasal approach (EEA) has improved access to the ventral skull base whilst retaining the principles of minimally invasive surgery. Despite the advantages these approaches offer, cerebrospinal fluid (CSF) rhinorrhoea remains a common complication. There is currently a lack of comparative evidence to guide the best choice of skull base reconstruction, resulting in considerable heterogeneity of current practice. This study aims to determine: (1) the scope of the methods of skull base repair; and (2) the corresponding rates of postoperative CSF rhinorrhoea in contemporary neurosurgical practice in the UK and Ireland. Methods We will adopt a multicentre, prospective, observational cohort design. All neurosurgical units in the UK and Ireland performing the relevant surgeries (TSA and EEA) will be eligible to participate. Eligible cases will be prospectively recruited over 6 months with 6 months of postoperative follow-up. Data points collected will include: demographics, tumour characteristics, operative data), and postoperative outcomes. Primary outcomes include skull base repair technique and CSF rhinorrhoea (biochemically confirmed and/or requiring intervention) rates. Pooled data will be analysed using descriptive statistics. All skull base repair methods used and CSF leak rates for TSA and EEA will be compared against rates listed in the literature. Ethics and dissemination Formal institutional ethical board review was not required owing to the nature of the study – this was confirmed with the Health Research Authority, UK. Conclusions The need for this multicentre, prospective, observational study is highlighted by the relative paucity of literature and the resultant lack of consensus on the topic. It is hoped that the results will give insight into contemporary practice in the UK and Ireland and will inform future studies.

Multiple spontaneous skull base cerebrospinal fluid leaks: some insights from an international retrospective collaborative study.

Spontaneous skull base cerebrospinal fluid leaks occurring without any apparent cause are rare. But those patients that present such leaks simultaneously, or successively, in multiple locations are even rarer. Given the rarity of this condition, we collected data from other groups in a multicentre study to reach an adequate number of patients and draw some preliminary considerations. We carried out a multicentre retrospective study on a cohort of patients treated at third level hospitals in Italy, Spain, United Kingdom and Greece for multiple spontaneous-CSF leaks and we compared them with a control group of patients treated for recurrent spontaneous-CSF leaks. Data regarding clinical aspects, radiological findings, surgical techniques and outcome were collected and preliminary considerations on the results were discussed. A total of 25 patients presented multiple simultaneous spontaneous CSF leaks while 18 patients fit with the criteria of recurrent spontaneous CSF leaks. Data analysis was conducted separately. Our understanding of the pathogenesis of this condition is currently very limited. A causative role of IIH may be present but the differences that emerged from the comparison with patients with recurrent fistulas seem to promote the possible role of other cofactors. A longer follow-up period is needed, and, in our opinion, prospective and multicentre studies are the only solution to seriously deal with such a complex topic.