Cerebrospinal Fluid Diversion in Endoscopic Skull Base Reconstruction

Special Considerations in Pediatric Endoscopic Skull Base Surgery

Originally pioneered in adults, endoscopic endonasal approaches for skull base pathology are being increasingly applied as a minimally invasive alternative for young children. Intrinsic anatomic differences between these patient populations have sparked discussions on the feasibility, safety, and efficacy of these techniques in pediatric patients. This work aims to serve as a primer for clinicians engaged in the rapidly evolving field of pediatric endoscopic skull base surgery. A succinct overview of relevant embryology, sinonasal anatomy, and diagnostic workup is presented to emphasize key differences and unique technical considerations. Additional discussions regarding select skull base lesions, reconstructive paradigms, potential surgical complications, and postoperative care are also highlighted in the setting of multidisciplinary teams.

Exploration of the causes of cerebrospinal fluid leakage after endoscopic endonasal surgery for sellar and suprasellar lesions and analysis of risk factors

Objective

Postoperative cerebrospinal fluid (CSF) leakage following endoscopic endonasal surgery (EES) is a frequent complication. This study aims to identify potential risk factors of postoperative CSF leakage.

Methods

A retrospective review of 360 patients who underwent EES was included. The associations between postoperative CSF leakage and patient demographics, medical history, tumor characteristics, and intraoperative repair techniques were analyzed; the diagnosis and repair of postoperative CSF leakage were also introduced.

Results

Postoperative CSF leakage occurred in 14 patients (3.9%), 2 of them cured by lumbar cistern drainage, 12 underwent endoscopic repair. Among these 12 cases, 3 were repaired twice, and the rest were cured the first time. During the repair surgery, insufficient embedded fat was detected in one case detected, seven with breached inner artificial dura, three had vascularized pedicle nasoseptal flap (VP-NSF) displacement, two with VP-NSF perforation, two with VP-NSF inactivation, and one with imperfect adherence to VP-NSF to the skull base. Eight cases had intracranial infections. Excluding one case who died of severe intracranial infection, the rest were cured and discharged without obvious sequelae. Multivariate analysis revealed that the suprasellar lesion, subarachnoid invasion, and intraoperative grade 3 flow CSF leakage were the risk factors of CSF leakage after operation, while the bone flap was a protective factor.

Conclusion

Bone flap combined with VP-NSF and iodoform gauze for skull base reconstruction is recommended in high-risk patients, while postoperative lumbar cistern drain remains dispensable.

Experience and modification of skull base reconstruction results in lower complications rates

OBJECTIVES

To investigate the efficacy of nasal septum bone flap combined with vascularized pedicle nasoseptal flap (VP-NSF) in the treatment of high-flow cerebrospinal fluid (CSF) leakage in the endonasal endoscopic skull base surgery.

METHODS

A total of 156 patients in group A used a multi-layer skull base reconstruction method of fat-absorbable artificial dura mater- fascia lata-VP-NSF, and were treated with drainage of the lumbar cistern after surgery, in addition, a total of 94 patients in group B used a multi-layer skull base reconstruction method of fat-absorbable artificial dura mater-nasal septal bone flap-VP-NSF, and no lumbar cistern drainage was performed after surgery. Analyzed and compared the differences of postoperative cerebrospinal fluid rhinorrhea, intracranial infection, re-repair, average bed rest time, pulmonary infection and deep venous thrombosis of lower extremities were analyzed and compared in the two groups.

RESULTS

In group A, 11 cases of cerebrospinal fluid rhinorrhea occurred after operation. In addition, 15 cases developed intracranial infection. During this period, there were 20 cases of pulmonary infection and 3 cases of deep venous thrombosis of lower extremities. In group B, there were 1 case of cerebrospinal fluid rhinorrhea (P < 0.05), 2 cases of intracranial infection (P < 0.05), 2 cases of pulmonary infection (P < 0.05), and 0 case of deep venous thrombosis of lower extremities (P > 0.05).

CONCLUSION

Nasal septum bone flap combined with VP-NSF is effective in the treatment of high-flow CSF leaks in the endonasal endoscopic skull base surgery, which can avoid postoperative lumbar cistern drainage and is worth popularizing.

Conservative Management of Post-Operative Cerebrospinal Fluid Leak following Skull Base Surgery: A Pilot Study

Background/aims: Iatrogenic CSF leaks after endoscopic endonasal transsphenoidal surgery remain a challenging entity to manage, typically treated with CSF diversion via lumbar drainage. Objective: To assess the safety and efficacy of high-volume lumbar puncture (LP) and acetazolamide therapy to manage iatrogenic CSF leaks. Methods: We performed a prospective pilot study of four patients who developed iatrogenic postoperative CSF leaks after transsphenoidal surgery and analyzed their response to treatment with concomitant high-volume lumbar puncture followed by acetazolamide therapy for 10 days. Data collected included demographics, intra-operative findings, including methodology of skull base repair and type of CSF leak, time to presentation with CSF leak, complications associated with high-volume LP and acetazolamide treatment, and length of follow-up. Results: Mean patient age was 44.28 years, with an average BMI of 27.4. Mean time from surgery to onset of CSF leak was 7.71 days. All four patients had resolution of their CSF leak at two- and four-week follow-up. Mean overall follow-up time was 179 days, with a 100% CSF leak cure rate at the last clinic visit. No patient suffered perioperative complications or complications secondary to treatment. Conclusion: Although our pilot case series is small, we demonstrate that a high-volume LP, followed by acetazolamide therapy for 10 days, can be considered in the management of post-operative CSF leaks.

Endoscopic endonasal resection of sinonasal teratocarcinosarcoma with intracranial breakthrough: illustrative case

BACKGROUND

Teratocarcinosarcoma traversing the anterior skull base is rarely reported in literature. The heterogenous and invasive features of the tumor pose challenges for surgical planning. With technological advancements, the endoscopic endonasal approach (EEA) has been emerging as a workhorse of anterior skull base lesions. To date, no case has been reported of EEA totally removing teratocarcinosarcomas with intracranial extensions.

OBSERVATIONS

The authors provided an illustrative case of a 50-year-old otherwise healthy man who presented with left-sided epistaxis for a year. Imaging studies revealed a 31 × 60-mm communicating lesion of the anterior skull base. Gross total resection via EEA was achieved, and multilayered skull base reconstruction was performed.

LESSONS

The endoscopic approach may be safe and effective for resection of extensive teratocarcinosarcoma of the anterior skull base. To minimize the risk of postoperative cerebrospinal fluid leaks, multilayered skull base reconstruction and placement of lumbar drainage are vitally important.

Intraoperative Indocyanine Green Angiography for Assessing Flap Perfusion in Skull Base Reconstruction: A Systematic Review

Objective This study was aimed to study the current use of intraoperative indocyanine green (ICG) angiography during skull base reconstruction and understand its efficacy in predicting postoperative magnetic resonance imaging (MRI) enhancement and flap.

Study Design The Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and Google Scholar databases were searched from the date of inception until August 2020 for studies of ICG flap perfusion assessment during skull base reconstruction. The primary outcome of interest was the development of cerebrospinal fluid (CSF) leak after skull base reconstruction. Secondary outcomes of interest included postoperative meningitis, flap MRI enhancement, flap necrosis, flap perfusion measurements, and total complications.

Results Search results yielded 189 studies, from which seven studies with a total of 104 patients were included in the final analysis. There were 44 nasoseptal flaps (NSF), two lateral nasal wall flaps (LNWF), 14 pericranial flaps (PCF), and 44 microvascular free flaps. The rates of CSF leak and postoperative MRI enhancement were 11 and 94%, respectively. There was one case of postoperative meningitis. Pooled analysis of the available data showed that intraoperative ICG flap perfusion was associated with flap enhancement on postoperative MRI (p = 0.008) and CSF leak (p = 0.315) by Fisher's exact test.

Conclusion The available literature suggests intraoperative ICG enhancement is associated with postoperative MRI enhancement. Given the small sample sizes in the literature and the rarity of complications associated with skull base reconstruction, intraoperative ICG enhancement has not been predictive of flap necrosis or postoperative complications such as CSF leak or meningitis.

Level of Evidence This study presents level 3 evidence as a systematic review of case studies, case reports, and retrospective and prospective trials with no blinding, controls, and inconsistently applied reference standards.

Modified Transpterygoid Approach to Sphenoid Meningoencephaloceles: A Shorter Run for a Longer Slide

OBJECTIVES

Cerebrospinal fluid (CSF) leaks and meningoencephaloceles originating in the lateral recess of the sphenoid sinus can be challenging. The traditional transpterygoid approach through the pterygopalatine fossa (PPF) is time consuming and places important structures at risk, which can lead to significant morbidity. We report a multi-institutional experience using a simplified, endoscopic modified transpterygoid approach (MTPA), which spares the PPF contents in the management of lateral sphenoid sinus meningoencephaloceles and CSF leaks.

STUDY DESIGN

Multi-Institutional, Retrospective Case Series.

METHODS

Patients with lateral sphenoid recess CSF leaks and meningoencephaloceles between 2014 and 2020 who underwent the MTPA at two academic medical centers were identified. Repair techniques and outcomes were evaluated.

RESULTS

Thirty-three patients underwent the MTPA for management. Skull base reconstruction was performed using a free mucosal graft (24/33, 72.7%), nasoseptal flap (4/33, 12.1%), bone grafts (3/33, 9.1%), and abdominal fat grafts (2/33, 6.1%). Lumbar drains and perioperative intracranial pressure measurements were routinely employed. Postoperative complications were uncommon and included three patients (9.7%) with temporary V2 anesthesia, one patient (3.2%) with prolonged V2 anesthesia, and one patient (3.2%) with subjective dry eye, all of which resolved at 9 months postoperatively. There were no recurrent CSF leaks resulting in a 100% success rate. Average follow-up was 13 months.

CONCLUSION

The MTPA reduces morbidity and greatly simplifies access to the lateral sphenoid sinus for the management of CSF leaks and meningoencephaloceles, without compromising exposure. This technique avoids the need for extensive PPF dissection and should be considered for the management of benign lesions involving the lateral sphenoid sinus.

LEVEL OF EVIDENCE

IV Laryngoscope, 2021.

Lumbar drains: Practical understanding and application for the otolaryngologist

INTRODUCTION

Lumbar drains are frequently used in patients with otolaryngologic concerns. These can be used therapeutically or prophylactically with the primary purpose being to modulate CSF pressure. Within otolaryngology, lumbar drains are most frequently used for cerebrospinal fluid leaks - either due to cerebrospinal fluid fistulas or in skull base surgery as these allow for potential healing of the defect. While not typically placed by otolaryngologists, a basic understanding of lumbar drains is beneficial in the context of patient management.

MANAGEMENT

A lumbar drain is inserted into the intrathecal space in a patient's lumbar spine. Though considered to be a benign procedure, complications are relatively frequent, and adjustment or replacement of the drain may be required. Complications include infection, epidural bleeding, retained hardware, sequelae of relative immobility, or may relate to over-drainage, ranging from mild headache to cranial neuropathies, altered mental status, pneumocephalus, intracranial hemorrhage, and death. While in place, neurologic exams should be performed routinely and should include motor and sensory exams of the lower extremities. A patient should be monitored for fevers, nuchal rigidity, and other signs of infection or meningitis. The CSF fluid should be grossly examined to identify changes, but routine laboratory tests are not typically run on the fluid itself. Drainage rates will vary usually between 5 and 20 mL per hour and must be frequently reassessed and adjusted based upon signs of intracranial hypotension. Drains should be removed when appropriate and should not be left in more than 5 days due to the increased infectious risk.

CONCLUSION

Lumbar drains are important tools used in patients with otolaryngologic pathologies. Otolaryngologists and otolaryngology residents should be familiar with these catheters to determine if they are working correctly and to identify adverse effects as early as possible.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Efficacy and Safety of Intraoperative Lumbar Drain in Endoscopic Skull Base Tumor Resection: A Meta-Analysis

Objectives: This study aims to evaluate the efficacy and safety of lumbar drainage (LD) in preventing cerebrospinal fluid (CSF) leaks after endoscopic skull base tumor resection. Methods: A systematic online search was conducted using PubMed, Embase, Scopus, Web of Science, and Cochrane Library from January 2006 to July 2019. Data analyses were performed by the Cochrane Collaboration's Review Manager 5.3 software. Results: Eight studies, including two randomized controlled trials and six observational studies, met the inclusion criteria. No significant difference was found in the post-operative CSF leak rate between the LD group and the non-LD group [odds ratio (OR), 0.80; 95%CI, 0.37-1.74; I 2 = 37%; P = 0.57). Subgroup analysis of the intraoperative high-flow leaks, including 4 studies and 313 patients, showed that LD was associated with reduced likelihood of post-operative CSF leak (OR, 0.37; 95%CI, 0.17-0.83; I 2 = 0%; P = 0.02). The placement of LD was related to increased risk of headache compared with non-LD use, and no significant difference was found in the occurrence of deep vein thromboses and pulmonary emboli between two groups. Conclusion: LD is not recommended in all patients undergoing endoscopic skull base tumor resection. However, for patients with intraoperative high-flow leaks, LD is effective and safe in reducing risk of CSF leak.

The expanded endonasal approach in pediatric skull base surgery: A review

OBJECTIVE

Surgery of the pediatric skull base has multiple unique challenges and has seen recent rapid advances. The objective of this review is to assess key issues in pediatric skull base surgery (SBS), including anatomic limitations, surgical approaches, reconstruction techniques, postoperative care, complications, and outcomes.

DATA SOURCES

PubMed literature review.

REVIEW METHODS

A review of the literature was conducted to assess the challenges, recent advances, and reported outcomes in pediatric SBS.

RESULTS

The pediatric skull base presents multiple anatomic challenges, including variable patterns of pneumatization, narrow piriform aperture width, and narrow intercarotid distance at the level of the cavernous sinus but not the superior clivus. These issues may be particularly challenging in patients less than 2 years of age. Endoscopic endonasal approaches in the sagittal and coronal plane have been applied to the pediatric skull base while open approaches may still be necessary in the setting of extensive intracranial or orbital disease, as well as disease lateral to critical neurovascular structures. While the nasoseptal flap was initially called into question for pediatric cases, it has been shown through multiple reports to be a feasible and robust reconstructive option. Complications and outcomes often depend upon the pathology. In children, response to noxious stimuli, ability to avoid Valsalva, and adherence to nasal precautions is variable. The use of lumbar drains is more common in pediatric than adult patients.

CONCLUSION

While the pediatric skull base presents unique challenges, outcomes data support that endoscopic endonasal approaches are a pertinent surgical technique in appropriately selected patients.

LEVEL OF EVIDENCE

3a.

Pediatric pituitary adenomas

BACKGROUND

Pediatric pituitary adenomas are a rare medical entity that makes up a small portion of intracranial tumors in children and adolescents. Although benign, the majority of these lesions are secreting functional tumors with the potential for physiological sequela that can profoundly affect a child's development.

FOCUS OF REVIEW

In this review, we discuss the medical and surgical management of these tumors with a focus on clinical presentation, diagnostic identification, surgical approach, and associated adjuvant therapies. We will also discuss our current treatment paradigm using endoscopic, open, and combined approaches to treat these tumors. The management of pituitary tumors requires a multidisciplinary team of surgeons, endocrinologists, and neuroanesthesiologists as well as neurocritical care specialists to deliver comprehensive care.

Pediatric craniopharyngioma

BACKGROUND

Craniopharyngioma has historically been recognized to be a formidable pathology primarily due to its proximity to critical neurovascular structures and the challenging surgical corridors that surgeons have tried to reach this lesion.

FOCUS OF REVIEW

In this work, we review the medical and surgical management of these tumors with a focus on clinical presentation, diagnostic identification, surgical approach, and associated adjuvant therapies. We will also discuss our current treatment paradigm using endoscopic, open, and combined approaches to craniopharyngiomas. The management of craniopharyngiomas requires a multidisciplinary team of surgeons, endocrinologists, and neuroanesthesiologists as well as neurocritical care specialists to deliver the most comprehensive and safest surgical resection with minimal postoperative morbidity.

Anatomical Risk Factors for Intraoperative Cerebrospinal Fluid Leaks During Transsphenoidal Surgery for Pituitary Adenomas

BACKGROUND

Cerebrospinal fluid (CSF) fistulas are among the most clinically important and frequent complications of transsphenoidal surgery for pituitary adenomas. Between the adenoma and the CSF, a "barrier" exists that consists of ≤3 elements. These, from cephalad to caudad, are the arachnoid, dura mater (sellar diaphragm), and pituitary glandular tissue. The objective of the present study was to determine whether the presence or absence of any of these 3 anatomical elements would be associated with the development of an intraoperative CSF fistula.

METHODS

From November 2016 to June 2018, 40 patients with pituitary adenomas underwent surgery, by transsphenoidal endonasal access, under a microscope. All procedures were filmed in 3 dimensions. The intraoperative findings and preoperative magnetic resonance images were analyzed and compared. The patients who had developed a fistula were compared against those who had not.

RESULTS

In 20 patients, glandular tissue was identified between the tumor and subarachnoid space. In 13, dura mater was evident, and in 7, only the arachnoid was noted. An intraoperative CSF fistula occurred in 6 patients, all of whom had the arachnoid as the only barrier. The presence of a fistula was significantly more likely statistically for patients with an arachnoid-only barrier than for those with any other barrier composition (P < 0.001).

CONCLUSIONS

The anatomical architecture forming the roof of the pituitary fossa is an important determinant of intraoperative CSF fistula risk. When the barrier consists of only the arachnoid, the risk will be significantly greater than when the barrier contains additional elements. Preoperative magnetic resonance imaging would be useful to determine the type of the existing barrier.

Skull base reconstruction with pedicled nasoseptal flap: Technique, indications, and limitations

Endoscopic skull base surgery allows extensive tumor resection but results in large defects requiring robust dural repair. The vascularized nasal septal flap pedicled on the posterior nasal septal artery is known to have an excellent success rate for dural defect coverage. Detailed step-by-step descriptions of the harvest and placement of this flap are scarce. Using a sketch, images, and a video, we describe a detailed method for endoscopically harvesting and placing a nasoseptal flap (NSF). We also describe the indications and the decision process leading to the use of NSF.

The Effect of lumbar drains on spontaneous cerebrospinal fluid leak repair

Objectives:

To address the factors affecting recurrence after endoscopic surgical repairs of spontaneous cerebrospinal fluid leak, specifically the influence of using lumbar drains.

Methods:

This study involved a retrospective data analysis, including a chart review of all spontaneous cerebrospinal fluid (CSF) leak cases who underwent endoscopic anterior skull base repair from 2012-2017 in King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia.

Results:

Thirteen patients with spontaneous CSF leaks were identified and evaluated. The majority were females (92.3%) with an average body mass index of 34.9. All patients underwent endoscopic repair with intra-operative lumbar drain placement. Patients continued having post-operative lumbar drain for an average of 6.4 days. Four patients (30.8%) developed recurrence; however, only one of those had a documented high opening pressure.

Conclusion:

Spontaneous CSF leak repairs are at a higher failure risk and may have an underlying pathology involving CSF circulation. The use of lumbar drains and intracranial pressure lowering agents are controversial and seems to be reserved only for high risk patients; however, the higher risk of recurrence in this group may be better managed by proper pre-operative evaluation and selective, patient-specific management protocols.

Avoiding complications in endoscopic skull base surgery

PURPOSE OF REVIEW

Endoscopic skull base surgery has become an established approach for the removal of tumors and cerebrospinal fluid fistulae repair. Compared with external approaches, it provides better aesthetic results and quality of life postoperatively. However, as it becomes popular and expands its indications possible complications should be reassessed in terms of incidence and variability in order to confirm its efficacy and safety. This article reviews the recent literature describing the main categories of possible complications suggesting strategies to minimize their incidence.

RECENT FINDINGS

Detailed preoperative planning based on imaging and histology can prevent major complications. Intraoperative use of image guidance and meticulous hemostasis provide the surgical field needed to avoid complications. Postoperative patient counseling, along with close and detailed nasal postoperative care are significant factors for an optimal outcome.

SUMMARY

Monitoring of complications after endoscopic skull base surgery is necessary in order to standardize protocols of management and improve our surgical techniques. The presence of late onset complications underlines the need of a special focus in postoperative care and follow-up.

The Role of the Lumbar Drain in Endoscopic Endonasal Skull Base Surgery: A Retrospective Analysis of 811 Cases

OBJECTIVE

With increasing use of the endoscopic endonasal transsphenoidal approach, wider attention is being paid to treatment and prevention of its complications. The aim of this study was to determine whether lumbar drainage (LD) has been effective in preventing and treating postoperative cerebrospinal fluid (poCSF) leakage or in assisting in achieving tumor gross total removal (GTR).

METHODS

Retrospective analysis of purely endoscopic endonasal transsphenoidal cases at a single center between 2008 and 2017 was done. We studied intraoperative cerebrospinal fluid (ioCSF) and poCSF leakage rates, duration of hospitalization, and GTR rate of the lesions, comparing patients with and without LD.

RESULTS

Among 811 endoscopic endonasal transsphenoidal procedures, LD was used in 38 cases. There was no statistically significant difference between patients with and without LD with regard to incidence of ioCSF leakage. A statistically significant difference was found in obese patients with LD, who had an apparently increased rate of poCSF leak. The length of stay of patients with LD was significantly longer than the control group without LD. The GTR rate was also higher in patients without LD.

CONCLUSIONS

Use of LD is correlated with longer immobilization and hospitalization without providing statistically significant advantages in terms of prevention or treatment of ioCSF and/or poCSF in low-risk and high-risk patients. Moreover, LD was not helpful in achieving GTR of tumors.

Survey of endoscopic skull base surgery practice patterns among otolaryngologists

Background

Endoscopic skull base surgery (ESBS) is a rapidly expanding field. Despite divergent reported preferences for reconstructive techniques and perioperative management, limited data exist regarding contemporary practice patterns among otolaryngologists performing ESBS. This study aims to elucidate current practice patterns, primarily the volumes of cases performed and secondarily a variety of other perioperative preferences.

Methods

An anonymous 32‐item electronic survey examining perioperative ESBS preferences was distributed to the American Rhinologic Society membership. Statistical significance between variables was determined utilizing Student t, chi‐square, and Fisher exact tests.

Results

Seventy otolaryngologists completed the survey. The effective response rate was approximately 22.5%. Sixty percent of respondents were in full‐time academic practice and 70% had completed rhinology/skull base fellowships. Annually, 43.3 mean ESBS cases were performed (29.1 private practice vs. 52.9 academic practice, P = .009). Academic practice averaged 24.1 expanded cases versus only 11 in private practice (P = .01). Of respondents, 55.7% stood on the same side as the neurosurgeon and 72.9% remained present for the entire case. Current procedural terminology coding and antibiotic regimens were widely divergent; 31.4% never placed lumbar drains preoperatively, while 41.4% did so for anticipated high‐flow cerebrospinal fluid leaks. While considerable variation in reconstructive techniques were noted, intradural defect repairs utilized vascularized flaps 86.3% of the time versus only 51.3% for extradural repairs (P < 0.001). Major complications were rare. Postoperative restrictions varied considerably, with most activity limitations between 2–8 weeks and positive airway pressure use for 2–6 weeks. Most respondents started saline irrigations 0–2 weeks postoperatively.

Conclusions

Based on responses from fellowship‐ and non‐fellowship‐trained otolaryngologists in various practice settings, there remains considerable variation in the perioperative management of patients undergoing ESBS.

Level of Evidence

5

Management of Skull Base Defects After Surgical Resection of Sinonasal and Ventral Skull Base Malignancies

Over the past 2 decades, there has been a significant increase in the resection of larger and more complex ventral skull base malignancies. The resection of these lesions has resulted in the creation of larger and more difficult to repair skull base defects. There are many available options for ventral skull base reconstruction. Despite the variety of reconstructive options, the key objective is to eliminate any communication between the intracranial space and the sinonasal cavity. This article discusses some of the more common techniques currently used for repair of these skull base defects.

Predictors and incidence of orthostatic headache associated with lumbar drain placement following endoscopic endonasal skull base surgery

BACKGROUND

Orthostatic headache (OH) is a potential complication of lumbar drainage (LD) usage. The incidence and risk factors for OH with the use of lumbar drainage during endoscopic endonasal procedures have not been documented.

OBJECTIVE

To investigate the incidence of post-procedure OHs associated with placement of LD in patients undergoing endoscopic endonasal procedures.

METHODS

We prospectively noted the placement of LDs in a consecutive series of endoscopic endonasal skull base surgeries. Charts were retrospectively reviewed, and patients were divided into two groups: those with OH and those without. The patient demographics, drain durations, imaging findings of intracranial hypotension, pathologies and need for a blood patch were compared between the two groups.

RESULTS

Two hundred forty-nine patients were included in the study. Seven patients (2.8%) suffered post-dural puncture OH, which was mild to moderate and disappeared 2-8 days (median 3 days) after treatment. Blood patches were used in four patients. Significant predisposing factors were age (33.0 vs. 53.5, P = 0.014) and a strong trend for female gender (85.7% vs. 47.9%, P = 0.062). BMI and drain duration were not significant. Postoperative intracranial hypotension was diagnosed radiographically in 43% of OH patients and in 5.4% of those without OH (P = 0.003). Four (1.6%) patients required treatment with an epidural blood patch.

CONCLUSION

OH associated with intracranial hypotension in patients undergoing endoscopic endonasal procedures with LDs is an infrequent complication seen more commonly in young female patients. Radiographic signs of intracranial hypotension are a specific but not sensitive test for OH.

Role of lumbar drains in contemporary endonasal skull base surgery: Meta-analysis and systematic review

BACKGROUND

Historically, lumbar drains (LD) have played a prominent role in endonasal skull base surgery. Over the past few decades, advancements in techniques have augmented our ability to successfully reconstruct complex skull base defects and often obviates the need for cerebrospinal fluid (CSF) diversion. Clarity on the appropriate use of LDs is needed.

OBJECTIVE

To examine the literature for the need for LDs in contemporary skull base reconstruction after resection of skull base tumors.

METHODS

A systematic literature review of English language articles by using PubMed and Ovid. Search terms included "lumbar drain," "CSF leak," and "endoscopic endonasal reconstruction." Articles were included when they pertained to adults, used current methods for reconstruction (i.e., multilayered repair or vascularized tissue), and addressed CSF leak rates secondary to endoscopic resection of skull base masses. All the studies discussed CSF leaks that resulted from traumatic-, idiopathic-, or sinus surgery-related iatrogenic causes were excluded. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed.

RESULTS

A total of five articles met inclusion criteria. These comprised 376 endoscopic skull base tumor resection and reconstruction cases; 5.59% developed postoperative CSF leaks. A meta-analysis was conducted by incorporating three studies that met criteria based on testing for heterogeneity. The average odds ratio for postoperative CSF leak for patients who did not have an LD relative to patients who had an LD was 0.590 (95% confidence interval, 0.214-1.630). Given a p value of 0.30, the results demonstrated a lack of statistically significant improvement between patients who had an LD and patients who did not have an LD. Various details, such as the defect size and type of CSF leak, were not consistently reported among studies.

CONCLUSIONS

Available evidence for the use of LDs in skull base surgery is of poor quality. Analysis of the literature revealed heterogenous and varied reporting in the primary literature. Further studies that include randomized controlled trials are needed.

Efficacy of Perioperative Lumbar Drainage following Endonasal Endoscopic Cerebrospinal Fluid Leak Repair: A Meta-analysis

Objective

Perioperative lumbar drain (LD) use in the setting of endoscopic cerebrospinal fluid (CSF) leak repair is a well-established practice. However, recent data suggest that LDs may not provide significant benefit and may thus confer unnecessary risk. To examine this, we conducted a meta-analysis to investigate the effect of LDs on postoperative CSF leak recurrence following endoscopic repair of CSF rhinorrhea.

Data Sources

A comprehensive search was performed with the following databases: Ovid MEDLINE (1947 to November 2015), EMBASE (1974 to November 2015), Cochrane Review, and PubMed (1990 to November 2015).

Review Method

A meta-analysis was performed according to PRISMA guidelines.

Results

A total of 1314 nonduplicate studies were identified in our search. Twelve articles comprising 508 cases met inclusion criteria. Overall, use of LDs was not associated with significantly lower postoperative CSF leak recurrence rates following endoscopic repair of CSF rhinorrhea (odds ratio: 0.89, 95% confidence interval: 0.40-1.95) as compared with cases performed without LDs. Subgroup analysis of only CSF leaks associated with anterior skull base resections (6 studies, 153 cases) also demonstrated that lumbar drainage did not significantly affect rates of successful repair (odds ratio: 2.67, 95% confidence interval: 0.64-11.10).

Conclusions

There is insufficient evidence to support that adjunctive lumbar drainage significantly reduces postoperative CSF leak recurrence in patients undergoing endoscopic CSF leak repair. Subgroup analysis examining only those patients whose CSF leaks were associated with anterior skull base resections demonstrated similar results. More level 1 and 2 studies are needed to further investigate the efficacy of LDs, particularly in the setting of patients at high risk for CSF leak recurrence.