Prevention and Management of Cerebrospinal Fluid Fistula After Transtemporal Skull Base Surgery

The incidence of cerebrospinal fluid (CSF) fistula after transtemporal skull base surgery can range from 4% to 19%. The risk of CSF leak may be related to tumor size and location, the extent of the dural defect, and the technical aspects of the wound reconstruction. Prevention of meningitis depends on the early detection and management of CSF leakage. Five hundred eighty-nine patients underwent a variety of transtemporal surgical approaches for the extirpation of skull base tumors at our institution from July 1988 to October 1999. The medical records were reviewed retrospectively to identify the tumor histology, size, and location, as well as the surgical approach, defect reconstruction technique, and the incidence of postoperative CSF leak. The risk of CSF fistulae was greatest in using the retrosigmoid approach (8%) and lowest in those who underwent a translabyrinthine approach (4%). Tumor size had no bearing on the incidence of the CSF leak and the overall incidence of meningitis was 1.0%. This article outlines our institutional objective for the prevention and management of CSF fistula after transtemporal skull base surgery. Illustrative cases will be presented.     

Subtotal petrosectomy in the treatment of cerebrospinal fluid fistulae of the lateral skull base

Cerebrospinal fluid (CSF) fistulae almost invariably lead to meningitis, even in the absence of other clinically obvious sequelae of the fistula such as a CSF fluid leak. The only effective means of reducing the risk of meningitis is surgical closure of the fistula. If surgery is to be recommended to patients with CSF fistulae even if they are currently asymptomatic, the morbidity of the procedure must be a principal determinant of the chosen technique. Recovery after the extracranial approach to a CSF fistula is much more rapid than after an intracranial procedure. The extracranial route is also free of the long-term risk of epilepsy which accompanies a craniotomy. The principal disadvantage of the lateral extracranial approach, failure of treatment, has been largely eliminated following studies into the obliteration of simple bony cavities using free adipose grafts. This paper describes our use of the extracranial approach to closure of CSF fistulae of the lateral skull base.     

The versatile extended pericranial flap for closure of skull base defects

OBJECTIVE: We sought to demonstrate the technical aspects of the extended pericranial flap and its versatility in reconstruction of a variety of skull base defects. STUDY DESIGN: We conducted a retrospective chart review of 32 patients who underwent reconstruction of skull-base defects with an extended pericranial flap by the senior author (Y.D.) from September 1997 to July 2003. METHODS: Patients with skull base defects after trauma or extirpative surgery were reconstructed with either a lateral- or an anterior-based vascularized extended pericranial flap. Variables and outcomes measured included: the size and anatomical location of the defect, need for other flaps, preoperative and/or postoperative radiation therapy and/or chemotherapy, bone flap necrosis, hardware exposure, wound dehiscence, postoperative cerebrospinal fluid (CSF) leak, and meningitis. RESULTS: There was no evidence of flap failure, 2 cases of transient (3 to 4 days) CSF leak without resultant meningitis, 3 patients with hardware exposure, and 2 patients with hydroxyapatite infection. The 2 transient cases of CSF leak both resolved without further surgical intervention or the placement of a lumbar drain. CONCLUSION: Both the lateral and anteriorly based extended pericranial flaps are reliable and versatile flaps associated with minimal morbidity and a low rate of complications when used to reconstruct defects of the anterolateral skull base.     

The Association of Meningitis with Postoperative Cerebrospinal Fluid Fistula

Objective To determine the risk factors for and the clinical course of postoperative meningitis following lateral skull base surgery and to determine its relationship to cerebrospinal fluid (CSF) fistula.Patients Patients undergoing lateral skull base surgery between July 1999 and February 2010 at an academic tertiary referral center. All subjects had culture-proven meningitis or suspected bacterial meningitis in the postoperative period. Medical records were compared with the lateral skull base patients who did not develop meningitis.Results Of 508 procedures, 16 patients developed meningitis (3.1%). The most common diagnosis was acoustic neuroma in 81.3%; 68.8% of patients had a CSF leak prior to onset of meningitis, and 50% received a lumbar drain. The median time from surgery to the onset of meningitis was 12 days with a range of 2 to 880 days. The relative risk of developing meningitis in the setting of postoperative CSF fistula is 10.2 (p < 0.0001). No meningitis-associated mortality was observed.Conclusions Postoperative meningitis occurred in a small number of patients undergoing lateral skull base surgery. A postoperative CSF fistula leads to an increased risk of meningitis by a factor of 10.2.     

Treatment of traumatic cerebrospinal fluid rhinorrhea via extended extradural anterior skull base approach

Objective: To describe and assess the repair technique and perioperative management for cerebrospinal fluid (CSF) leak resulting from extensive anterior skull base fracture via extradural anterior skull base approach. Methods: This was a retrospective review conducted at the Department of Neurosurgery of the Shanghai Tenth People''s Hospital from January 2015 to April 2020. Patients with traumatic CSF rhinorrhea resulting from extensive anterior skull base fracture treated surgically via extended extradural anterior skull base approach were included in this study. The data of medical and radiological records, surgical approaches, repair techniques, peritoperative management, surgical outcome and postoperative followup were analyzed. Surgical repair techniques were tailored to the condition of associated injuries of the scalp, bony and dura injuries and associated intracranial lesions. Patients were followed up for the outcome of CSF leak and surgical complications. Data were presented as frequency and percent. Results: Thirty-five patients were included in this series. The patients’ mean age was 33 years (range 11-71 years). Eight patients were treated surgically within 2 weeks; while the other 27 patients, with prolonged or recurrent CSF rhinorrhea, received the repair surgery at 17 days to 10 years after the initial trauma. The mean overall length of follow-up was 23 months (range 3-65 months). All the patients suffered from frontobasal multiple fractures. The basic repair tenet was to achieve watertight seal of the dura. The frontal pericranial flap alone was used in 20 patients, combined with temporalis muscle and/or its facia in 10 patients. Free fascia lata graft was used instead in the rest 5 patients. No CSF leak was found in all the patients at discharge. There was no surgical mortality in this series. Bilateral anosmia was the most common complication. At follow-up, no recurrent CSF leak or meningitis occurred. No patients developed mucoceles, epidural abscess or osteomyelitis. One patient ultimately required ventriculoperitoneal shunt because of progressive hydrocephalus. Conclusion: Traumatic CSF rhinorrhea associated with extensive anterior skull base fractures often requires aggressive treatment via extended intracranial extradural approach. Vascularized tissue flaps are ideal grafts for cranial base reconstruction, either alone or in combination with temporalis muscle and its fascia—fascia lata sometimes can be opted as free autologous graft. The approach is usually reserved for patients with traumatic CSF rhinorrhea in complex frontobasal injuries.     

Endoscopic Endonasal Transclival Approaches: Case Series and Outcomes for Different Clival Regions

Objective Transclival endoscopic endonasal approaches to the skull base are novel with few published cases. We report our institution''s experience with this technique and discuss outcomes according to the clival region involved. Design Retrospective case series. Setting Tertiary care academic medical center Participants All patients who underwent endoscopic endonasal transclival approaches for skull base lesions from 2008 to 2012. Main Outcome Measures Pathologies encountered, mean intraoperative time, intraoperative complications, gross total resection, intraoperative cerebrospinal fluid (CSF) leak, postoperative CSF leak, postoperative complications, and postoperative clinical course. Results A total of 49 patients underwent 55 endoscopic endonasal transclival approaches. Pathology included 43 benign and 12 malignant lesions. Mean follow-up was 15.4 months. Mean operative time was 167.9 minutes, with one patient experiencing an intraoperative internal carotid artery injury. Of the 15 cases with intraoperative cerebrospinal fluid (CSF) leaks, 1 developed postoperative CSF leak (6.7%). There were six other postoperative complications: four systemic complications, one case of meningitis, and one retropharyngeal abscess. Gross total resection was achieved for all malignancies approached with curative intent. Conclusions This study provides evidence that endoscopic endonasal transclival approaches are a safe and effective strategy for the surgical management of a variety of benign and malignant lesions. Level of Evidence 4.     

A management algorithm for cerebrospinal fluid leak associated with anterior skull base fractures: detailed clinical and radiological follow-up

Detailed outcome data for the management of anterior skull base fractures associated with cerebrospinal fluid (CSF) leakage is lacking. We present detailed follow-up data of a single-center study using a predetermined algorithm for the management of CSF leakage secondary to traumatic fractures. A number of 138 consecutive patients were included in the analysis; all patients underwent high-resolution computed tomography (CT) scanning at time of admission with β₂-transferrin testing used to confirm CSF leakage. Patients with acute surgical indications were operated as emergent; leaks were repaired at the time of initial surgery in patients with intracranial pressure < 15 cm H₂O. The remainder of the study population was managed conservatively including use of prophylactic antibiotics; lumbar drainage (LD) catheters were placed in those patients with leakage persisting beyond 48 h. Leaks lasting longer than 5 days underwent microsurgical repair using an intradural bicoronal approach. One-year follow-up assessment included evaluation of neurological status, Glasgow Outcome Scale (GOS), and repeat head CT. Twenty eight patients (26.9%) underwent emergent surgery, 15 of whom had simultaneous CSF leak repair, whereas 76 patients (73.1%) underwent delayed CSF leak repair between days 5 and 14. Postoperative meningitis rate was low (1.9%). Postoperative CSF leak (1.9%) was managed by intradural or transnasal endoscopic operation. Comparable rates of anosmia and frontal lobe hypodensities were seen in the surgical and conservatively managed subgroups. The presented algorithm, utilizing prophylactic antibiotics, trial of LD, acute and/or delayed intradural microsurgery, yields favorable outcomes. Large randomized controlled trials are needed to better define the role of prophylactic antibiotics and to better characterize the optimal timing and approach of surgical repair.     

Endonasal endoscopic repair of ethmoid roof cerebrospinal fluid fistula by suturing the dura

Introduction  Over the past 20years, improvement in surgical techniques as well advances in surgical instruments for sinus surgery has led to surgical closure of cerebrospinal fluid (CSF) leak using endoscopic approach. Minimally invasive and having lower post op morbidity, compared to traditional intracranial techniques, repairing CSF leak endoscopically has evolved to become the standard practice for management of CSF leak. Discussion  Widespread use of endoscope in sinus surgery have made us more familiar with the anatomy of the sinuses as well as the skull base. In this paper, we will describe our experience of CSF repair by suturing dura under endoscopic guidance for the repair of small ethmoid roof (<1.2cm) defects.     

Skull base reconstruction in the extended endoscopic transsphenoidal approach for suprasellar lesions

OBJECT: The extended transsphenoidal approach to the suprasellar region has the advantages of minimal invasiveness and brain manipulation in the surgical treatment of small to medium lesions. At the same time, however, it carries a higher risk of postoperative cerebrospinal fluid (CSF) leakage and related complications than those for the standard transsphenoidal approach. Effective reconstruction of large skull base defects is a major concern in such extended approaches and remains challenging. METHODS: Between January 2004 and April 2006, 21 patients affected by different suprasellar lesions underwent the extended endoscopic endonasal transtuberculum-transplanum approach. Three different techniques were used for the skull base reconstructions. In all cases, dehydrated human pericardium (Tutoplast) for dural reconstruction and a copolymer of L-lactic acid and glycolic acid (LactoSorb) as a bone substitute were used. Collagen sponges, fibrin glue, and an inflated Foley balloon catheter were also used to fill the sphenoid sinus cavity. RESULTS: Two cases of postoperative CSF leaks (9.5%) and one case of mycotic sinusitis (4.8%) occurred following the intradural (inlay) and intraextradural (inlay-overlay) graft positioning. No cases of postoperative CSF leakage occurred in cases in which the extradural-only reconstruction procedure was applied. No meningitis or other complications related to the closure were noticed. CONCLUSIONS: The rate of postoperative CSF leakage after an extended approach to the suprasellar area is higher compared with that following standard pituitary surgery. Reconstruction after craniopharyngioma surgery exposes patients to an increased risk of postoperative CSF leaks. The extradural (overlay) technique was found to be the most effective in assuring a watertight closure.     

Acute traumatic CSF fistulae: the risk of intracranial infection

The management of acute traumatic cerebrospinal fluid (CSF) fistulae is still a matter of debate and hinges about what is perceived to be the risk of subsequent intracranial infection. We have therefore carried out a retrospective analysis of 160 cases of traumatic CSF leaks to assess the incidence, cumulative risk and prognosis of intracranial infection. The overall incidence of meningitis in this group before surgical dural repair was 30.6% (49/160), the cumulative risk exceeded 85% at 10 years follow-up and the meningitis was fatal in 4.1% (2/49). The recurrence of CSF leakage after initial spontaneous cessation was 7% and meningitis was recurrent in 30.6% (15/49). Prophylactic antibiotics had reduced the risk of meningitis from 61 to 34%. The commonest pathogen was pneumococcus and the CSF leakage had stopped within 7 days in 60% of those who developed meningitis and in 50% of those who did not develop meningitis. Meningitis is still a serious complication of post-traumatic CSF fistulae and is potentially fatal despite modern therapeutic agents.     

BioGlue for prevention of postoperative cerebrospinal fluid leaks in transsphenoidal surgery: A case series

BACKGROUND: The efficacy of BioGlue (CryoLife, Inc, Atlanta, Ga) surgical adhesive in transsphenoidal surgery was assessed as an adjunct in the prevention of postoperative CSF leaks. METHODS: All patients in whom BioGlue was used for an intraoperative skull base reconstruction were retrospectively identified. Intraoperative CSF leaks were graded according to size (grade 1, small weeping leak without obvious diaphragmatic defect; grade 2, moderate leak with a definite diaphragmatic defect; grade 3, large diaphragmatic and/or dural defect). CSF leak repair was tailored to CSF leak grade. BioGlue was applied as a reinforcement over collagen sponge as the last layer of the repair. RESULTS: Over 28 months, a total of 282 patients underwent endonasal surgery. Of these patients, 124 (79 women; age range, 8-84 years), in 128 procedures, had an intraoperative CSF leak repair reinforced with BioGlue. Pathology included 80 pituitary adenomas, 11 craniopharyngiomas, 7 Rathke's cleft cysts, 6 chordomas, 5 meningiomas, 4 spontaneous CSF leaks, 3 arachnoid cysts, and 8 other parasellar pathologies. There were 62 (48.4%) grade 1, 41 (32.0%) grade 2, and 25 (19.5%) grade 3 leak repairs. The overall repair failure rate was 1.6% (2 cases), with the failures occurring in patients with grade 3 leaks, including 1 who developed meningitis; there was no failure of grades 1 and 2 leaks. The 2 failures were attributed largely to technical aspects of the repair rather than to failure of BioGlue per se. CONCLUSIONS: BioGlue appears to be an effective adjunct in preventing postoperative CSF leaks after transsphenoidal surgery. However, careful attention to technical details of the repair is still required to prevent failures, especially when closing large dural and diaphragmatic defects.     

Does Meningitis Stop CSF Rhinorrhea following Lateral Skull Base Surgery?

In cases of cerebrospinal fluid (CSF) rhinorrhea following lateral skull base surgery, fibrosis and fibrin formation resulting from meningitis has been postulated as a mechanism of spontaneously resolving the CSF leak. This study was undertaken to explore any possible relationship between the cessation of CSF leak and meningitis. A retrospective study at a tertiary referral center of 232 consecutive patients was performed. Out of a total of 232 procedures, 29 patients developed CSF rhinorrhea, of whom 7 subsequently developed meningitis. Bacteria were isolated in CSF obtained at lumbar puncture in 5 cases, with the CSF analysis in the remaining 2 cases suggesting aseptic meningitis. Conservative treatment failed to stop the CSF rhinorrhea in 6 of 7 cases. In this study, the development of meningitis did not appear to aid in the resolution of the CSF rhinorrhea. We conclude that surgical intervention should not be delayed in the expectation that meningitis and conservative interventions may promote CSF leak resolution.     

Post-traumatic CSF fistulae, the case for surgical repair

The management of acute post-traumatic CSF fistulae is still a matter of controversy. A long-term analysis of 160 patients with acute post-traumatic non-iatrogenic dural fistulae was undertaken to establish the value of surgical dural repair. One hundred and forty-nine patients underwent dural repairs following traumatic CSF rhinorrhoea. The risk of meningitis following surgical dural repair was 4%. The operative mortality was 1.3% (2/151), as was the negative exploration rate. The first dural repair was successful in 90% and a second dural repair was required in 10%. These results are in favour of surgical dural repair which can be undertaken with a low morbidity and mortality and is highly successful in preventing meningitis following traumatic CSF rhinorrhoea.     

Post-traumatic cerebrospinal fluid leakage

Posttraumatic cerebrospinal fluid (CSF) leakage frequently complicates skull base fractures. While most CSF leaks will cease without treatment, patients with persistent CSF leaks may be at increased risk for meningitis, and many will require surgical intervention. We reviewed the medical records of 51 patients treated between 1984 and 1998, with CSF leaks that persisted for 24 hours or longer after head trauma. Twenty-eight patients (53%) had spontaneous resolution of the leakage at an average of 5 days. Twenty-three patients (47%) required surgery. Eight patients (16%) had occult leaks presenting with recurrent meningitis at an average of 6.5 years posttrauma. Forty-three (84%) patients with CSF leaks had an associated skull fracture, most commonly involving the frontal sinus, while only 18 patients (35%) had parenchymal brain injury or extra-axial hematoma. Eight patients (16%) had delayed leaks at an average of 13 days posttrauma. Among patients with clinically evident CSF leakage the frequency of meningitis was 10% with antibiotic prophylaxis, and 21% without antibiotic prophylaxis. Thus, prophylactic antibiotic administration halved risk of meningitis. A variety of surgical approaches was used, with minimal morbidity. Three of 23 surgically treated patients (13%) required additional surgery for continued leakage. Patients with CSF leaks that persist greater than 24 hours are at risk for meningitis, and many will require surgical intervention. Prophylactic antibiotics may be effective and should be considered in this group of patients. Patients with skull fractures involving the skull base or frontal sinus should be followed for delayed leakage. Surgical outcome is excellent.     

Skull base cerebrospinal fluid fistulas: A comprehensive diagnostic algorithm

OBJECTIVE: Our goal was to assess the efficacy of current diagnostic modalities in the management of skull base cerebrospinal fluid (CSF) fistulas. METHODS: We conducted a retrospective review of all patients presenting to our institution over the past 6 years with skull base CSF fistulas. RESULTS: Fifty-two patients were included in the study. beta2-Transferrin analysis of collected specimen was the most efficacious means of confirming a CSF leak. High-resolution computed tomography was the most informative radiographic study, yielding a sensitivity and an accuracy of 87%. Magnetic resonance cisternography, yielding a sensitivity and an accuracy of 78%, was instrumental in localizing the site of leak for a few cases but was most commonly corroborative. Using a graduated diagnostic approach, successful repair was attained in 88% of cases after 1 attempt and 98% after 1 or 2 attempts. CONCLUSION: For patients with skull base CSF fistulas, a graduated diagnostic approach with emphasis on confirmation of leak by beta2-transferrin analysis and precise localization by high-resolution computed tomography is both efficacious and cost effective.     

A comprehensive algorithm for anterior skull base reconstruction after oncological resections.

Objective: To present our method for anterior skull base reconstruction after oncological resections. Methods: One hundred nine patients who had undergone 120 anterior skull base resections of tumors (52 malignant [43%], 68 benign [57%]) via the subcranial approach were studied. Limited dural defects were closed primarily or reconstructed using a temporalis fascia. Large anterior skull base defects were reconstructed by a double-layer fascia lata graft. A split calvarial bone graft, posterior frontal sinus wall, or three-dimensional titanium mesh were used when the tumor involved the frontal, nasal, or orbital bones. A temporalis muscle flap was used to cover the orbital socket for cases of eye globe exenteration, and a rectus abdominis free flap was used for subcranial-orbitomaxillary resection. Pericranial flap wrapping of the frontonaso-orbital segment was performed to prevent osteoradionecrosis if perioperative radiotherapy was planned. Results: The incidence of cerebrospinal fluid (CSF) leak, intracranial infection, and tension pneumocephalus was 5%. Histopathological and immunohistochemical analysis of fascia lata grafts in reoperated patients (n = 7) revealed integration of vascularized fibrous tissue to the graft and local proliferation of a newly formed vascular layer embedding the fascial sheath. Conclusion: A double-layer fascial graft alone was adequate for preventing CSF leak, meningitis, tension pneumocephalus, and brain herniation. We describe a simple and effective method of anterior skull base reconstruction after resections of both malignant and benign tumors.     

Reduction of cerebrospinal fluid rhinorrhea after vestibular schwannoma surgery by reconstruction of the drilled porus acusticus with hydroxyapatite bone cement

OBJECT: Cerebrospinal fluid (CSF) rhinorrhea remains a significant cause of morbidity after resection of vestibular schwannomas (VSs), with rates of rhinorrhea after this procedure reported to range between 0 and 27%. The authors investigated whether reconstruction of the drilled posterior wall of the porus acusticus with hydroxyapatite cement (HAC) would decrease the incidence of postoperative CSF rhinorrhea. METHODS: A prospective observational study of 130 consecutive patients who underwent surgery for reconstruction of the posterior wall of the drilled porus acusticus with HAC was conducted between October 2002 and September 2005. All patients underwent a retrosigmoid transmeatal approach for VS resection and were followed up to document cases of CSF rhinorrhea, incisional CSF leak, meningitis, or rhinorrhea-associated meningitis. A cohort of 150 patients with VSs who were treated with the same surgical approach but without HAC reconstruction served as a control group. RESULTS: The authors found that HAC reconstruction of the porus acusticus wall significantly reduced the rate of postoperative CSF rhinorrhea in their patients. In the patients treated with HAC, rhinorrhea developed in only three patients (2.3%) compared with 18 patients (12%) in the control group. This was a statistically significant finding (p = 0.002, odds ratio = 5.8). CONCLUSIONS: The use of HAC in the reconstruction of the drilled posterior wall of the porus acusticus, occluding exposed air cells, greatly reduces the risk of CSF rhinorrhea.     

The Management of Spontaneous Otogenic CSF Leaks: A Presentation of Cases and Review of Literature

Objective The types of otogenic cerebrospinal fluid (CSF) fistulae were previously classified into defects through, adjacent to, or distal to the otic capsule. This article presents cases of the three different types of spontaneous CSF fistulae and reviews pertinent literature. We examine the management of the different types of otogenic CSF leaks with modern audiovestibular testing, imaging, and surgical techniques. Design Case series and review of the literature. Setting Academic tertiary neurotologic referral practice. Participants Four patients identified through a retrospective search. Main outcome measures Resolution of CSF leak and absence of meningitis. Results Surgical intervention was performed on the four cases described in this series; none had a return of CSF otorrhea in the postoperative period or meningitis. Conclusions Otogenic CSF fistulae may lead to life-threatening infection and in congenital forms are typically not diagnosed unless meningitis has occurred. Rapid and proper recognition, work-up, and treatment of such leaks decrease the risk of permanent neurologic sequelae as well as recurrent meningitis.     

Utilization of preoperative cerebrospinal fluid drain in skull base surgery.

OBJECTIVE: Retrospectively assess the efficacy of lumbar cerebrospinal fluid (CSF) drainage placed preoperatively in skull base operations in decreasing the incidence of postoperative CSF fistula. METHODS: A retrospective review of 150 patients undergoing a posterior fossa craniotomy from 1989 to 2000 was conducted. Patients were divided into those receiving preoperative lumbar drains and those that did not. The rates of postoperative CSF leakage were compared between the two groups. Patient data were analyzed to determine if there were other comorbidities affecting the postoperative incidence of CSF leakage such as smoking, diabetes, or hypertension. RESULTS: Between 1989 and 1994, 25/72 (35%) patients with no preoperative lumbar drain had a postoperative CSF leak. From 1995 to 2000, 9/78 (12%) patients with a preoperative lumbar drain had a CSF leak. This was a 23% decreased incidence of postoperative CSF leakage and a significant decrease in the probability (p < 0.001) of CSF leakage in patients treated with a preoperative lumbar drain. The comorbidities of diabetes, smoking, or hypertension did not increase the probability of a CSF leak (p = 0.43). CONCLUSIONS: A preoperatively placed lumbar drain can significantly lower the rate of postoperative CSF leakage after skull base surgery. The drain is a well-tolerated adjunct to dural closure and helps increase surgical exposure of the posterior fossa. The comorbidities of diabetes, smoking, or hypertension do not contribute to an increased rate of CSF leakage.dagger Lyal Leibrock M.D., F.A.C.S. is Deceased.