Surgical Management of Temporal Bone Cerebrospinal Fluid Leaks from the Posterior Cranial Fossa.

To compare patients surgically managed for spontaneous cerebrospinal fluid (CSF) leaks of the temporal bone arising from the middle cranial fossa (MCF) and posterior cranial fossa (PCF) and to describe the surgical management of posterior fossa CSF leaks. Retrospective case review. Academic tertiary center. Adult patients presenting with spontaneous temporal bone CSF leaks undergoing operative repair between January 2010 and August 2018. Patients with a history of trauma, previous mastoid surgery, and iatrogenic CSF leaks were excluded. Transmastoid or MCF CSF leak repair. Patient demographics, body mass index (BMI), comorbidities, presenting features, and lumbar puncture opening pressures were compared between groups and the management of the PCF CSF leaks described. Forty-six patients (26 women, 20 men) were included. The mean age at the time of repair was 58.0 ± 12.9 years (±SD). The origin of the CSF leak was from the PCF in three patients and MCF in 43 patients. All three patients with PCF leaks presented with an acute history of meningitis compared with only seven (16%) in the MCF group. This difference was statistically significant (p = 0.01, Fisher's exact test). There were no statistically significant differences in age, sex, BMI, or lumbar puncture opening pressures. The PCF leaks were repaired using a transmastoid approach with multilayer closure of the bony defect and fat graft obliteration of the mastoid. Spontaneous CSF leaks arising from the PCF are rare and may present more commonly with meningitis. Identification requires careful review of imaging.

Transmastoid Approach to Spontaneous Temporal Bone Cerebrospinal Fluid Leaks: Hearing Improvement and Success of Repair

Cerebrospinal fluid (CSF) leaks in the temporal bone arise from osteodural defects, resulting in an abnormal connection between the subarachnoid space and the adjacent tympanomastoid cavity, which often manifests as otorrhea. Patients typically exhibit symptoms such as headache, unilateral hearing impairment, aural fullness, or even meningitis. Imaging studies are critical for identifying and differentiating the location and characteristics of CSF leaks. However, when the leak's origin remains ambiguous, diagnostic surgery may be warranted to both confirm the diagnosis and facilitate treatment. This report discusses an uncommon case while reviewing relevant literature, focusing on the surgical diagnostic intervention in a 58-year-old male with spontaneous temporal bone CSF leaks. The patient, a 58-year-old man, was admitted for evaluation of left ear fullness, hearing loss, and nasal discharge. Notably, when supine, clear fluid drained from the left nasal cavity, with improvement noted upon sitting. A nasal examination did not reveal significant findings, while the otologic evaluation indicated an intact periosteum; however, considerable fluid accumulation was identified within the left middle ear. Despite undergoing multiple periosteal punctures and conservative medical management, the middle ear effusion persisted. Imaging studies, including magnetic resonance imaging (MRI) and computed tomography, confirmed the presence of left-sided CSF otorrhea, and the head MRI indicated potential CSF rhinorrhea. This raised challenges in determining whether the CSF leak originated from the sphenoid sinus or the temporal bone. Given that CSF otorrhea may drain through the external auditory canal and CSF rhinorrhea from the sellar region can present as nasal leakage, differentiation proved complex. In this case, with an intact external auditory canal, CSF from the middle ear was observed to flow into the nasal cavity via the Eustachian tube. Therefore, leakage from both sites could be misconstrued as CSF rhinorrhea, complicating the diagnostic process. Consequently, an exploratory surgical procedure was performed, revealing an incomplete dura mater on the temporal aspect of the petrous bone, which was subsequently repaired. Benign intracranial hypertension can result in meningeal protrusion or meningoencephalocele, which may lead to CSF leakage that generally responds favorably to mucosal repair. In instances where imaging fails to identify the source of the leak or when diagnostic options are limited, proactive exploratory surgery is advisable. Although surgical interventions carry inherent risks, the application of endoscopic techniques by experienced surgeons renders this approach a feasible choice for addressing both diagnostic and therapeutic challenges.

To compare outcomes of surgical repair of temporal bone encephalocele and cerebrospinal fluid (CSF) leak using fibrin glue-coated collagen (FGCC) complex patch versus other materials for repair of dura. Retrospective chart review. Tertiary care hospital. Fifty-two adult patients undergoing transmastoid (TM), middle fossa (MF) or combined approach repair of spontaneous MF CSF leak between 2016 and 2020. Exposure of bony defect via TM approach, MF craniotomy, or combined TM/MF, and repair of the associated dura defect with FGCC complex patch, or other materials (acellular collagen matrix, bovine collagen, autologous fascia, fibrin tissue sealant). Successful repair without recurrent CSF leak or encephalocele throughout follow-up. Cost of materials used in duraplasty. Sixty-four percent of patients were female. Mean (standard deviation) age at repair was 61.4 (12.1) years. Mean (standard deviation) body mass index was 35.0 (8.3) kg/m 2 . Forty-nine (94%) patients had successful repair without known recurrence of CSF leak or encephalocele over a median follow-up interval of 11.7 months. Average duraplasty material cost was significantly lower with FGCC in comparison with other nonautologous materials (FGCC+: $1259.94, FGCC-: $1652.58; p = 0.004). No significant differences in recurrence risk (FGCC+: 6.9%, FGCC-: 6.9%; p > 0.999) or operative time (FGCC+: 153.7 min, FGCC-: 155.4 min; p = 0.88) were detected based on material used for duraplasty. All materials studied demonstrate effective and sustained means of repair for MF CSF leak and encephalocele, including in the presence of multiple defects. Use of FGCC for duraplasty produces noninferior surgical results to other nonautologous materials in repair of spontaneous CSF leaks of the temporal bone and may be more cost-effective.

Aspiration pneumonitis (AP) secondary to cerebrospinal fluid (CSF) leak is underestimated and rarely discussed. This study aimed to evaluate the association between AP and CSF leaks. Clinical and surgical characteristics of CSF leak patients with and without AP between January 2010 and December 2022 were included and compared. This study included 159 patients, 16 with CSF otorrhea and 143 with CSF rhinorrhea. Among them, 40 (25.2%) had AP. Bilateral pneumonitis was identified in 32 cases, of which 11 showed severe pneumonitis in the right upper lung lobe. Twenty-one (52.5%) asymptomatic and 19 (47.5%) symptomatic cases were documented. The major clinical manifestations included cough (n=19, 47.5%) and expectoration (n=9, 22.5%). The prevalence of pneumonitis was significantly higher in the spontaneous group than in the traumatic group. High-flow CSF leak was associated with AP (42.5%vs. 16.8%, p=0.001). No significant differences were identified in defect locations between patients with and without AP. Patients with pneumonitis had a higher prevalence of meningitis (32.5%vs. 12.6%, p=0.003). Multiple logistic regression results revealed that meningitis, spontaneous and high-flow CSF leaks are independent factors for AP occurrence. Both the CSF leak and pulmonary complications resolved following successful surgical repair. AP secondary to CSF leaks is frequently underdiagnosed, with a higher incidence identified in spontaneous cases. The occurrence of AP was associated with high-flow CSF leak. A pneumonitis rate of 25.2% in cerebrospinal fluid (CSF) leak patients was reported for the first time. A higher prevalence of aspiration pneumonitis was identified in spontaneous CSF leak. Meningitis, spontaneous and high-flow CSF leaks are independent factors for aspiration pneumonitis occurrence.

Spontaneous temporal bone cerebrospinal fluid leak may be defined as a leak without an apparent precipitating cause. These transdural fistulas occur rarely, and diagnosis is predicated upon a high index of suspicion. Leaks have been reported through both middle and posterior fossa defects, although the vast majority involve the middle fossa plate. In a previous study we reported 7 cases of spontaneous temporal bone cerebrospinal fluid leaks, all involving the middle fossa tegmen. Upon further review of these cases and 5 previously unreported cases, the defect was localized to the tegmen tympani in 9 of the total 12 cases. Diagnostic methods are discussed, with the importance of high-resolution computed tomography stressed. The role of contrast cisternography is also evaluated. An outline for surgical management is presented based upon residual hearing and defect location and accessibility. A transmastoid procedure offers the advantage of visualization of both the middle and posterior fossa plates, and this approach can be supplemented with an obliterative procedure when indicated. The middle fossa approach provides optimal exposure of the tegmen plate with less likelihood of ossicular injury when dealing with tegmen tympani defects. Adjuncts to surgical therapy include intrathecal fluorescein dye and continuous postoperative lumbar cerebrospinal fluid drainage.

Intraoperative cerebrospinal fluid (CSF) leaks are associated with increased risk of postoperative CSF leaks despite multilayered reconstruction with vascularized tissue. A recent randomized controlled trial (RCT) examining the use of perioperative lumbar drains (LD) in high-risk skull base defects identified a significant reduction in postoperative CSF leak incidence (21.2 vs. 8.2%; p = 0.017). This study was conducted to assess the efficacy of the selective use of CSF diversion, for patients with intraoperative CSF leaks involving endoscopic endonasal approaches (EEA) to the skull base. Method Consecutive endoscopic endonasal surgeries of the skull base from a pre-RCT cohort and post-RCT cohort were compared. The following case characteristics between the two cohorts were examined: patient age, body mass index (BMI), rate of revision surgery, tumor histology, use of CSF diversion, and vascularized reconstruction. The primary measured outcome was postoperative CSF leak. Results The pre-RCT cohort included 76 patients and the post-RCT cohort included 77 patients, with dural defects in either the anterior or posterior cranial fossa (pituitary and parasellar/suprasellar surgeries excluded). There was a significant reduction in the incidence of postoperative CSF leak in the post-RCT cohort (27.6 vs. 12.9%; p = 0.04). On subgroup analysis, there was a trend toward improvement in CSF leak rate of the anterior cranial fossa (19.2 vs. 10.5%; p = 0.27), whereas CSF leak rates of the posterior cranial fossa were significantly reduced compared with the pre-RCT cohort (41.4 vs. 12.8%; p = 0.02). Conclusion This study demonstrates that the integration of selective CSF diversion into the reconstructive algorithm improved postoperative CSF leak rates.

Spontaneous Cerebrospinal Fluid Leak through the Posterior Aspect of the Petrous Bone

Microvascular decompression (MVD) using a retrosigmoid approach is a highly effective, open-surgical procedure for neurovascular conflict in the posterior fossa, although there is a risk of postoperative cerebrospinal fluid (CSF) leak. To identify factors associated with postoperative CSF leakage after MVD. We retrospectively reviewed all patients who underwent MVDs at our institution from 2007 to 2020. Patient demographics, clinical diagnoses, and procedural characteristics were recorded and compared. Factors leading to CSF leak were analyzed using χ 2 , univariate, and multivariate regression. Of 1011 patients who underwent MVDs, 37 (3.7%) presented with postoperative CSF leaks. In univariate analysis, the use of Cranios/Norian to obliterate the air cells was protective against CSF leak ( P = .01). Craniotomies ( P = .002), the use of dural substitutes such as Durepair ( P = .04), dural onlays such as DuraGen ( P = .04), muscle/fascia ( P = .03), and titanium mesh cranioplasty >5 cm ( P = .03) were associated with CSF leak. On multivariate analysis, only the presence of craniotomies ( P = .04) and nonprimary dural closure ( P = .03) were significant risk factors for CSF leak. When excluding the 34 (3.4%) patients who underwent a craniotomy, the lack of primary dural closure still remained significantly associated with postoperative CSF leak ( P = .04). Our results represent one of the largest series of posterior fossa surgeries for a uniform indication in North America. Our study demonstrates increased risk for postoperative CSF leak when craniotomies are performed and when primary dural closure is not established. Given the small sample of patients who received a craniotomy, however, future studies corroborating this finding should be performed.

Spontaneous cerebrospinal fluid (CSF) leak is one of the types of non-traumatic CSF leaks in which the etiologic factor is unknown. Skull base defects transnasal endoscopic plasty is the initial method of surgical repair of spontaneous cerebrospinal fluid leaks. METHODS: Forty-five patients with spontaneous CSF leaks were managed using multilayer transplant technique. The basic choice criteria of endoscopic transnasal surgical approach and materials to reconstruction of skull base defects were the size of defect and its localization. In all cases pediculated flaps in combination with free graft were used. RESULTS: In 43 (96%) cases CSF leaks was successfully managed in primary surgery, which indicates high efficiency of the described surgical interventions.

Advances in endoscopic skull base (SB) surgery have led to the resection of increasingly larger cranial base lesions, resulting in large SB defects. These defects have initially led to increased postoperative cerebrospinal fluid (CSF) leaks. The development of the vascularized pedicled nasoseptal flap (PNSF) has successfully reduced postoperative CSF leaks. Mucocele formation, however, has been reported as a complication of this technique. In this study, we analyze the incidence of mucocele formation after repair of SB defects using a PNSF. A retrospective review was performed from December 2008 to December 2011 to identify patients who underwent PNSF reconstruction for large ventral SB defects. Demographic data, defect site, incidence of postoperative CSF leaks, and rate of mucocele formation were collected. Seventy patients undergoing PNSF repair of SB defects were identified. No postoperative mucocele formation was noted at an average radiological follow-up of 11.7 months (range, 3–36.9 months) and clinical follow-up of 13.8 months (range, 3–38.9 months), making the overall mucocele rate 0%. The postoperative CSF leak rate was 2.9%. Proper closure of SB defects is crucial to prevent CSF leaks. The PNSF is an efficient technique for these repairs. Although this flap may carry an inherent risk of mucocele formation when placed over mucosalized bone during repair, we found that meticulous and strategic removal of mucosa from the site of flap placement resulted in a 0% incidence of postoperative mucocele formation in our cohort.

Radical excision of meningioma is suggested to provide for the best tumor control rates. However, aggressive surgery for meningiomas located at the posterior cranial fossa may lead to elevated postoperative morbidity of adjacent cranial nerves which in turn worsens patients' postoperative quality of life. Therefore, we analyzed our institutional database with regard to new cranial nerve dysfunction as well as postoperative cerebrospinal fluid (CSF) leakage depending on the extent of tumor resection. Between 2009 and 2017, 89 patients were surgically treated for posterior fossa meningioma at the authors' institution. Postoperative new cranial nerve dysfunction as well as CSF leakage were stratified into Simpson grade I resections with excision of the adjacent dura as an aggressive resection regime versus Simpson grade II-IV tumor removal. Simpson grade I resections revealed a significantly higher percentage of new cranial nerve dysfunction immediately after surgery (39%) compared with Simpson grade II (11%, p = 0.01) and Simpson grade II-IV resections (14%, p = 0.02). These observed differences were also present for the 12-month follow-up (27% Simpson grade I, 3% Simpson grade II (p = 0.004), 7% Simpson grades II-IV (p = 0.01)). Postoperative CSF leakage was present in 21% of Simpson grade I and 3% of Simpson grade II resections (p = 0.04). Retreatment rates did not significantly differ between these two groups (6% versus 8% (p = 1.0)). Elevated levels of postoperative new cranial nerve deficits as well as CSF leakage following radical tumor removal strongly suggest a less aggressive resection policy to constitute the surgical modality of choice for posterior cranial fossa meningiomas.

Spontaneous cerebrospinal fluid (CSF) leaks are a morbid condition associated with operative intervention for treatment. Understanding associations are key to diagnosis, treatment, and possible early detection. To determine the clinical association and odds of having obstructive sleep apnea (OSA) and spontaneous CSF leaks. A comprehensive search of the literature was conducted using PubMed (MEDLINE), Cochrane Library, and relevant article bibliographies. Systematic review and meta-analysis of studies from 2005 to 2015 investigating spontaneous CSF leaks in patients with OSA. The CSF leaks were considered spontaneous when they occurred in the absence of trauma, surgery, infection, and neoplasm. Included studies provided the number of patients diagnosed as having OSA and spontaneous CSF leaks. Two independent investigators reviewed all studies for inclusion. The numbers of patients with OSA were systematically extracted from each study. Studies that compared the prevalence of OSA with spontaneous CSF leaks against their control cohort were pooled in the meta-analysis using a random-effects model. To determine whether there was increased incidence of OSA in patients with spontaneous CSF leaks. This hypothesis was formulated prior to data collection. The search criteria yielded 384 abstracts, and 6 clinical studies involving OSA and CSF leaks met the inclusion and exclusion criteria. They were all retrospective in nature and included 3 comparative (case-control) studies, 2 case series, and 1 case report. The cumulative reported prevalence of having OSA and spontaneous CSF leaks is 16.9% (232 of 1376 patients). Three of the studies were eligible for the meta-analysis. The odds of having OSA with a spontaneous CSF leak were 4.73 times more likely than in control cohorts (95% CI, 1.56-14.31; P = .006; I² = 35%). In a subgroup analysis of studies including nonspontaneous CSF leaks as their control cohort, the odds of having OSA with a spontaneous CSF leak were 2.85 times more likely than OSA with a nonspontaneous CSF leak (95% CI, 1.22-6.63; P = .02; I² = 0%). There was a notable difference in the age, BMI, or patients with hypertension in the comparative studies. The association between OSA and spontaneous CSF leaks as demonstrated by retrospective studies is confounded by heterogeneous patient characteristics. Large prospective controlled studies using polysomnography and elevated intracranial pressure measurements are required to further evaluate the relationship between OSA and spontaneous CSF leaks.

Spontaneous spinal cerebrospinal fluid (CSF) leaks are an increasingly recognized cause of intracranial hypotension and may require neurosurgical intervention. In the present report the authors review their experience with the surgical management of spontaneous spinal CSF leaks. Between 1992 and 1997, 10 patients with spontaneous spinal CSF leaks and intracranial hypotension were treated surgically. The mean age of the seven women and three men was 42.3 years (range 22-61 years). Preoperative imaging showed a single meningeal diverticulum in two patients, a complex of diverticula in one patient, and a focal CSF leak alone in seven patients. Surgical exploration in these seven patients demonstrated meningeal diverticula in one patient; no clear source of CSF leakage could be identified in the remaining six patients. Treatment consisted of ligation of the diverticula or packing of the epidural space with muscle or Gelfoam. Multiple simultaneous spinal CSF leaks were identified in three patients. All patients experienced complete relief of their headaches postoperatively. There has been no recurrence of symptoms in any of the patients during a mean follow-up period of 19 months (range 3-58 months; 16 person-years of cumulative follow up). Complications consisted of transient intracranial hypertension in one patient and leg numbness in another patient. Although the disease is often self-limiting, surgical treatment has an important role in the management of spontaneous spinal CSF leaks. Surgery is effective in eliminating the headaches and the morbidity is generally low. Surgical exploration for a focal CSF leak, as demonstrated on radiographic studies, usually does not reveal a clear source of the leak. Some patients may have multiple simultaneous CSF leaks.

Spontaneous spinal cerebrospinal fluid (CSF) leaks are rare (5 per 100,000 per year). Treatment generally consists of conservative therapy or interventional therapy with epidural blood patching. Surgical treatment is conducted rarely, usually in cases when conservative or interventional treatment has failed. The aim of our case series was to assess the clinical outcome after surgery. Our clinical database was reviewed for patients with spontaneous spinal CSF leaks who underwent surgical exploration between 2010 and 2013. Etiology, symptoms, preoperative imaging, type of required surgical method, intraoperative findings, and clinical outcome were reported. We identified five patients with a mean age of 62years with spontaneous spinal CSF leaks who were treated surgically. Two patients received surgery after failure of interventional treatment. The origin of the CSF leak could be identified intraoperatively in three cases. Surgical technique in all cases consisted of an interlaminar fenestration or hemilaminectomy and a complete foraminotomy to explore the thecal sack and the exiting nerve roots and identify the CSF leak. After surgery, the preoperative symptoms improved in all patients. In one case, there was a relapse after 4weeks. Preoperative identification of a CSF leak with MRI was positive in only one case. In all other cases, a post-myelography CT had to be performed. In all cases, the preoperative symptoms improved after surgery. Surgical treatment is an effective treatment of spontaneous cerebrospinal fluid leaks in cases of refractory symptoms after failed conservative or interventional treatment.