The use of the nasoseptal flap to reduce the rate of post-operative cerebrospinal fluid leaks following endoscopic trans-sphenoidal surgery for pituitary disease

Reconstruction of the Anterior Skull Base Using the Nasoseptal Flap: A Review

The nasoseptal flap is a workhorse reconstructive option for anterior skull base defects during endonasal surgery. This paper highlights the versatility of the nasoseptal flap. After providing a brief historical perspective, this review will focus on the relevant primary literature published in the last ten years. We will touch upon new applications of the flap, how the flap has been modified to expand its reach and robustness, and some of the current limitations. We will conclude by discussing what the future holds for improving upon the design and use of the nasoseptal flap in anterior skull base reconstruction.

"NIMS" nasal mucoperiosteal flap for sublabial trans-sphenoidal surgical defect repair: A new technique under microscope

Background:

CSF rhinorrhea is a known complication that may occur after cranial base surgery, especially the trans-sphenoidal approaches to sellar tumors. It may occur following both microscopic and endoscopic procedures. Over a period, the balance has tilted toward endoscopy due to development of pedicled Hadad flap. Microscopic trans-sphenoidal surgery (TSS) continues to be performed in our institute as well as many other centers across the world due to familiarity of technique and unavailability of endoscopic equipment. Despite the fairly widespread use of this surgery, literature is devoid of any description of a local mucosal flap for repair of the surgical defect in microscopic TSS.

Methods:

We herein described the procedure and our experience of harvesting such flap in 42 patients operated for pituitary adenomas in our department between September 2016 and February 2020, through microscopic sublabial TSS.

Results:

All 42 of the patients included in this study underwent excision of pituitary tumors (macroadenomas). Thirty-nine (n = 39) patients were undergoing 1^st time surgery, while three (n = 3) of these patients were undergoing second surgery following an earlier trans nasal trans-sphenoidal route. None of our cases have reported CSF leak postoperatively.

Conclusion:

This study attempts to highlight to ardent/obligate microscopic surgeons that a local vascularized flap can be harvested for repair of skull base defect and prevent postoperative CSF leak in microscopic sublabial TSS.

Sinonasal Quality of Life Outcomes after Endoscopic Endonasal Transsphenoidal Surgery with Posterior Septum Free Mucosal Graft Reconstruction

Objective  Quality of life (QoL) outcomes following endoscopic endonasal transphenoidal surgery (EETS) across a variety of reconstructive methods improve by 2 to 6 months. An option for sellar reconstruction, in the absence of a significant intraoperative cerebrospinal fluid (CSF) leak, is a free mucosal graft (FMG) from the posterior septum. We analyze sinonasal QoL outcomes in patients undergoing EETS with FMG reconstruction. Study Design  This study was a retrospective review. Setting  This study was conducted at tertiary care academic center. Participants  This study group consisted of patients undergoing EETS for pituitary adenomas from 2013 to 2018. Main Outcome Measures  Tumor and surgical factors were included, along with postoperative complications. Patients completed Sinonasal Outcome Test-22 (SNOT-22) questionnaires. Pre- and postoperative scores were compared among the entire cohort using linear multilevel regression. A subcohort analysis was performed among patients who completed questionnaires during the preoperative visit and two postoperative visits (within 1 month and between 2 and 3 months, respectively); pre- and postoperative total and individual domain SNOT-22 scores were compared using paired t -tests. Results  A total of 243 patients underwent EETS with FMG reconstruction. Four patients (1.6%) developed a postoperative CSF leak requiring reoperation. Among the entire cohort, SNOT-22 scores increased at the first postoperative visit ( p  < 0.01) but returned to baseline by the second, third, and fourth postoperative visits ( p  = 0.27, p  = 0.18, and p  = 0.21). Among 48 patients who completed both preoperative and two postoperative questionnaires, scores increased within the first month ( p  < 0.01) but returned to baseline at 2 to 3 months ( p  = 0.67). Conclusion  Posterior septum FMG reconstruction of sellar defects is an effective option, demonstrating early recovery of baseline sinonasal QoL by 2 to 3 months.

Heterogeneity in Outcome Reporting in Endoscopic Endonasal Skull Base Reconstruction: A Systematic Review

Objective  Presently, there are no standards for reporting outcomes of endoscopic endonasal skull base reconstruction (ESBR). This is problematic as a lack of consistent reporting makes synthesizing findings in systematic reviews and meta-analysis challenging. Thus, the aim of this study was to systematically review and describe the patterns of reporting outcomes in ESBR as a foundation for developing reporting guidelines. Study Design  Present study is a systematic review. Methods  Embase, PubMed, CINAHL, Cochrane Library, and Web of Science were searched for all publications with ≥25 patients and a focus on ESBR. The reporting patterns of each study's variables and outcomes were assessed. Results  A total of 112 studies were included in the review. The most commonly reported demographic variables were the number of included patients ( n  = 112, 100%) and types of pathologies treated ( n  = 104, 92.9%). Meanwhile, the most routinely described preoperative variable was history of prior treatment ( n  = 48, 42.9%). Type of reconstruction was a commonly reported intraoperative variable ( n  = 110, 98.2%), though the rate of intraoperative cerebrospinal fluid (CSF) leak was noted in only 76 studies (67.9%). With regard to postoperative outcomes, postoperative CSF leak rate was routinely provided ( n  = 101, 90.2%), but reporting of other surgical complications was more inconsistent. Ultimately, of the 43 variables and outcomes reviewed, a median of 12 (range: 4-22) was reported in each study. Conclusion  There is significant heterogeneity in the outcomes reported in studies relating to ESBR. This highlights the need for the development of standard reporting guidelines to minimize bias and improve interstudy comparability.

Complications after 1002 endoscopic endonasal approach procedures at a single center: lessons learned, 2010-2018

OBJECTIVE

The endoscopic endonasal approach (EEA) has evolved into a mainstay of skull base surgery over the last two decades, but publications examining the intraoperative and perioperative complications of this technique remain scarce. A prior landmark series of 800 patients reported complications during the first era of EEA (1998-2007), parallel to the development of many now-routine techniques and technologies. The authors examined a single-institution series of more than 1000 consecutive EEA neurosurgical procedures performed since 2010, to elucidate the safety and risk factors associated with surgical and postoperative complications in this modern era.

METHODS

After obtaining institutional review board approval, the authors retrospectively reviewed intraoperative and postoperative complications and their outcomes in patients who underwent EEA between July 2010 and June 2018 at a single institution.

RESULTS

The authors identified 1002 EEA operations that met the inclusion criteria. Pituitary adenoma was the most common pathology (n = 392 [39%]), followed by meningioma (n = 109 [11%]). No patients died intraoperatively. Two (0.2%) patients had an intraoperative carotid artery injury: 1 had no neurological sequelae, and 1 had permanent hemiplegia. Sixty-one (6.1%) cases of postoperative cerebrospinal fluid leak occurred, of which 45 occurred during the original surgical hospitalization. Transient postoperative sodium dysregulation was noted after 87 (8.7%) operations. Six (0.6%) patients were treated for meningitis, and 1 (0.1%) patient died of a fungal skull base infection. Three (0.3%) patients died of medical complications, thereby yielding a perioperative 90-day mortality rate of 0.4% (4 deaths). High-grade (Clavien-Dindo grade III-V) complications were identified after 103 (10%) EEA procedures, and multivariate analysis was performed to determine the associations between factors and these more serious complications. Extradural EEA was significantly associated with decreased rates of these high-grade complications (OR [95% CI] 0.323 [0.153-0.698], p = 0.0039), whereas meningioma pathology (OR [95% CI] 2.39 [1.30-4.40], p = 0.0053), expanded-approach intradural surgery (OR [95% CI] 2.54 [1.46-4.42], p = 0.0009), and chordoma pathology (OR [95% CI] 9.31 [3.87-22.4], p < 0.0001) were independently associated with significantly increased rates of high-grade complications.

CONCLUSIONS

The authors have reported a large 1002-operation cohort of EEA procedures and associated complications. Modern EEA surgery for skull base pathologies has an acceptable safety profile with low morbidity and mortality rates. Nevertheless, significant intraoperative and postoperative complications were correlated with complex intradural procedures and meningioma and chordoma pathologies.

Cerebrospinal fluid leakage repair of various grades developing during endoscopic transnasal transsphenoidal surgery

Objectives

We describe the strategy used to repair intraoperative leaks of various grades and define factors for preventing postoperative cerebrospinal fluid leakage (CSF) after surgery via the endoscopic endonasal transsphenoidal approach (EETA).

Study design

Retrospective chart review at a tertiary referral center.

Methods

Patients who underwent surgery via EETA from January 2009 to May 2020 were retrospectively reviewed. Intraoperative CSF leakage was graded 0–3 in terms of the dural defect size; various repairs were used depending on the grade.

Results

A total of 777 patients underwent 869 operations via EETA; 609 (70.1%) experienced no intraoperative CSF leakage (grade 0) but 260 (29.9%) did. Leakage was of grade 1 in 135 cases (15.5%), grade 2 in 83 (9.6%), and grade 3 in 42 (4.8%). In 260 patients with intraoperative CSF leakage, a buttress was wedged into the sellar defect site in 178 cases (68.5%) and a pedicled flap was placed in 105 cases (40.4%). Autologous fat (108 cases, 41.5%) and a synthetic dural substitute (91 cases, 35%) were used to fill the dead space of the sellar resection cavity. Postoperative CSF leakage developed in 21 patients: 6 of grade 1, 7 of grade 2, and 8 of grade 3. Buttress placement significantly decreased postoperative leakage in grade 1 patients (p = 0.041). In patients of perioperative leakage grades 2 and 3, postoperative CSF leakage was significantly reduced only when both fat and a buttress were applied (p = 0.042 and p = 0.043, respectively).

Conclusion

A buttress prevented postoperative CSF leakage in grade 1 patients; both fat and buttress were required by patients with intraoperative leakage of grades 2 and 3.

Reconstruction strategies for intraoperative CSF leak in endoscopic endonasal skull base surgery: systematic review and meta-analysis

BACKGROUND

Endoscopic endonasal surgery (EES) is one of the preferred options for skull base pathologies. Cerebrospinal fluid (CSF) leak is a significant complication of EES and neurosurgeons have proposed various reconstructive strategies to decrease this morbidity. We describe and compare the efficacy of these strategies.

METHODS

We searched PubMed, Cochrane Library, and Web of Science for publications between 1990 and November 2019. We defined a reconstruction hierarchy of seven levels from inside to outside: fat graft, intracranial intradural layer (inlay), intracranial extradural layer (onlay), buttress, mucosal flap, nasal packing and lumbar drainage. A single-arm analysis was performed for the primary outcome of CSF leak rate.

RESULTS

Of 3641 records identified, 48 studies met the inclusion criteria. Pituitary tumors had lower postoperative CSF leak rate than other diseases (1.8% vs. 6.5%, RD = -4.7% [-7.1%, -2.1%]). In high CSF flow group, the post-operative leak rate was reduced by application of mucosal flap (4.3% vs. without mucosal flap at 12.8%, RD = -8.5% [-15.1%, -1.9%]). The use of inlay showed potential of decreasing the post-operative leak rate (5.0% vs. 7.2%, RD = -2.2% [-7.7%, 3.3%]). In low CSF flow group, tampon was better than balloon for nasal packing (1.0% vs. 10.5%, RD = -9.5% [-16.5%, -2.4%]).

CONCLUSIONS

Mucosal flap and inlay for high-flow intraoperative CSF leak and tampon (compared with balloon) for low-flow intraoperative CSF leak, improved the postoperative CSF leak rate. Further studies are required to establish more robust evidence.

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.

Difference in the incidence of cerebrospinal fluid leakage and residual tumors between functional and nonfunctional pituitary adenomas treated by endoscopic transsphenoidal pituitary adenomectomy

Objective

This study compared the incidence of cerebrospinal fluid (CSF) leakage and residual tumors between functional and nonfunctional pituitary adenomas treated with the endoscopic endonasal transsphenoidal approach (EETA).

Methods

All patients underwent endocrine examinations and brain magnetic resonance imaging before and after surgery. The length of admission, incidence of central diabetes insipidus, incidence of CSF leakage, symptom relief, and presence of residual tumors were compared between patients with functional and nonfunctional pituitary adenomas.

Results

Thirty-eight patients were enrolled, among whom 12 and 26 had functional and nonfunctional pituitary adenomas, respectively. The incidence of CSF leakage was significantly higher in patients with nonfunctional adenomas; a hard or elastic tumor character accounted for the difference. A large tumor size and cavernous sinus invasion were risk factors for residual tumors. No significant differences were found in sex, length of admission, operative times, incidence of diabetes insipidus, or number of residual tumors between the two groups. The hormone levels were lower postoperatively than preoperatively in patients with nonfunctional adenomas.

Conclusion

Nonfunctional pituitary macroadenomas resulted in more CSF leakage. Use of the rescue nasoseptal flap reduced unnecessary nasal destruction. Cooperation between a neurosurgeon and otolaryngologist was safer and more effective when using the EETA.

Endoscopic Endonasal Reconstruction of High-Flow Cerebrospinal Fluid Leak with Fascia Lata "Button" Graft and Nasoseptal Flap: Surgical Technique and Case Series

Background  The endoscopic endonasal approach (EEA) has become increasingly used for resection of skull base tumors in the sellar and suprasellar regions. A nasoseptal flap (NSF) is routinely used for anterior skull base reconstruction; however, there are numerous additional allografts and autografts being used in conjunction with the NSF. The role of perioperative cerebrospinal fluid (CSF) diversion is also unclear. Objective  This study was aimed to analyze success of high-flow CSF leak repair during EEA procedures without use of CSF diversion through lumbar drainage. Methods  A retrospective chart review of patients who had intraoperative high-flow CSF leak during EEA procedures at our institution between January 2013 and December 2017 was performed. CSF leaks were repaired with use of a fascia lata button graft and nasoseptal flap, without use of perioperative lumbar drains. Results  A total of 38 patients were identified (10 male, 28 female). Patient BMIs ranged from 19.7 to 49 kg/m ² (median = 31 kg/m ² ), with 18 patients meeting criteria for obesity (BMI > 30 kg/m ² ) and 12 patients overweight (25 kg/m ²  < BMI < 29.9 kg/m ² ). There was no incidence of postoperative CSF leak. Conclusion  In our experience, the nasoseptal flap used in conjunction with the fascia lata button graft is a safe, effective and robust combination for cranial base reconstruction with high-flow intraoperative CSF leaks, without need for lumbar drains.

Sinonasal quality-of-life outcomes after endoscopic endonasal skull base surgery

BACKGROUND

There are substantial gaps in our understanding of the influence of the endoscopic endonasal approach (EEA) for endoscopic skull base surgery on sinonasal-specific quality of life (QOL) as well as the instruments available for assessment. Our primary objective in this study was to characterize postoperative changes in sinonasal QOL, specifically using the 22-item Sino-Nasal Outcome Test (SNOT-22), with a secondary objective of delineating weaknesses in our current understanding of patient symptomatology after EEA for skull base surgery.

METHODS

A comprehensive literature review was conducted using PubMed, CINAHL, Cochrane Library, and SCOPUS for studies reporting SNOT-22 data pre- and postoperatively in patients who underwent EEA for skull base pathologies. Studies were limited to patients ≥18 years of age and excluded patients diagnosed with chronic rhinosinusitis (CRS).

RESULTS

Nineteen unique studies with 27 separate data sets and a total of 1025 patients were used in this meta-analysis. Overall SNOT-22 scores statistically improved at the 6-month (p = 0.0009) and 1-year (p = 0.002) time-points. Patients with preoperative SNOT-22 scores ≥20 achieved postoperative improvements at 12-week (p < 0.00001), 6-month (p < 0.0001), 1-year (p < 0.00001), and long-term follow-up (p < 0.0001). Patients with preoperative SNOT-22 scores <20 remained stable and did not worsen postoperatively.

CONCLUSION

Patients undergoing EEA for skull base pathologies who have impaired sinonasal QOL preoperatively demonstrated significant postoperative QOL improvements. Those patients with relatively normal preoperative sinonasal QOL remained asymptomatic postoperatively. This study supports the need for development of a contemporary disease- and approach-specific, validated QOL instrument for skull base pathologies.

Vascularized Nasoseptal Flap for Medial Orbital Wall Reconstruction

With the use and efficacy of the vascularized nasoseptal flap, its indications are also expanding. Due to its relative ease of harvesting and no significant impairment in the long-term sinonasal quality of life, the flap has been used for a number of other purposes apart from its originally proposed use in reconstruction of the anterior cranial fossa, sella, and the clivus. Its use may negate the need of another incision to obtain fat or fascia. The authors describe the case of a 47-year-old lady who underwent endoscopic excision of a medially placed orbital intraconal hemangioma who presented to us with very poor vision in the left eye. The large medial orbital defect was reconstructed with a vascularized pedicled nasoseptal flap from the ipsilateral side. The patient made an excellent visual and sino-nasal recovery. This patient highlights a unique use for the proliferating indications for the use of the nasoseptal flap.

The posterior nasoseptal flap: A novel technique for closure after endoscopic transsphenoidal resection of pituitary adenomas

Background:

While effective for the repair of large skull base defects, the Hadad-Bassagasteguy nasoseptal flap increases operative time and can result in a several-week period of postoperative crusting during re-mucosalization of the denuded nasal septum. Endoscopic transsphenoidal surgery for pituitary adenoma resection is generally not associated with large dural defects and high-flow cerebrospinal fluid (CSF) leaks requiring extensive reconstruction. Here, we present the posterior nasoseptal flap as a novel technique for closure of skull defects following endoscopic resection of pituitary adenomas. This flap is raised in all surgeries during the transnasal exposure using septal mucoperiosteum that would otherwise be discarded during the posterior septectomy performed in binostril approaches.

Methods:

We present a retrospective, consecutive case series of 43 patients undergoing endoscopic transsphenoidal resection of a pituitary adenoma followed by posterior nasoseptal flap placement and closure. Main outcome measures were extent of resection and postoperative CSF leak.

Results:

The mean extent of resection was 97.16 ± 1.03%. Radiographic measurement showed flap length to be adequate. While a defect in the diaphragma sellae and CSF leak were identified in 21 patients during surgery, postoperative CSF leak occurred in only one patient.

Conclusions:

The posterior nasoseptal flap provides adequate coverage of the surgical defect and is nearly always successful in preventing postoperative CSF leak following endoscopic transsphenoidal resection of pituitary adenomas. The flap is raised from mucoperiosteum lining the posterior nasal septum, which is otherwise resected during posterior septectomy. Because the anterior septal cartilage is not denuded, raising such flaps avoids the postoperative morbidity associated with the larger Hadad-Bassagasteguy nasoseptal flap.

Risk Factors Predicting Nasoseptal Flap Failure in the Endoscopic Endonasal Transsphenoidal Approach

OBJECTIVE

Reconstruction of the skull base using a pedicled nasoseptal flap (NSF) seems to be advantageous after the endoscopic endonasal transsphenoidal approach (EETSA). A few reports have evaluated the cause of flap failure in EETSA using NSFs. The aim of this study was to evaluate the perioperative risk factors for NSF failure.

STUDY DESIGN

Patient series.

SETTING

Retrospective review of medical records at a tertiary referral center.

METHODS

The study population comprised patients who underwent EETSA with NSF elevation between February 2009 and March 2014. The authors retrospectively reviewed the all patients' medical records, including operative findings.

RESULTS

Four hundred thirteen patients (203 males and 210 females) underwent EETSA, and 315 patients underwent EETSA with NSF elevation. The mean patient age was 48.0 years. The total number of patients of NSF failure was 6 (overall rate: 1.61%, 6/315; flap elevation: 0.31%, 1/315; flap reconstruction: 15.1%, 5/33). Two patients had diabetes mellitus. One patient had cardiovascular problems. Five patients were elderly (>60 years; mean age: 70 years). Five patients had postoperative nasal infection. One patient underwent preoperative radiation therapy.

CONCLUSION

Nasoseptal flap is a usually safe and effective technique for skull base reconstruction. However, the management of patients with diabetes mellitus, cardiovascular problems, advanced age, postoperative nasal infection, and radiation therapy may require more attention to improve NSF survival.

An Algorithm for Sellar Reconstruction Following the Endoscopic Endonasal Approach: A Review of 300 Consecutive Cases

Objectives/Hypotheses  The endoscopic endonasal approach (EEA) is the workhorse endoscopic procedure for sellar and parasellar pathology. Various reconstruction techniques have been reported following EEA surgery, ranging from no reconstruction to vascularized flaps. We review our institution's experience with sellar reconstruction following EEA and propose an evidence-based algorithm. Design  Retrospective review. Setting  Tertiary academic medical center. Participants  Patients who underwent endoscopic EEA surgery for sellar or parasellar pathology between March 1, 2013 and August 31, 2016. Main Outcome Measures  Patient demographic and clinicopathologic data were collected. Outcome measures included intraoperative and postoperative cerebrospinal fluid (CSF) leak rates and extent of resection (gross or subtotal). Results  Three hundred consecutive patients were included. Depending on the presence and grade of intraoperative CSF leak, cases were reconstructed using either a free mucosal graft (FMG) or nasoseptal flap (NSF). Intraoperative and postoperative CSF leak rates were 30.7% and 2.3%, respectively. Multivariable logistic regression found that intraoperative CSF leak was associated with recurrent disease (odds ratio [OR] 2.47, p  = 0.004), with no apparent predictors of postoperative CSF leak. Conclusions  Based on this large series, we propose the following algorithm for sellar reconstruction: FMG for no CSF leak; fat graft + FMG ± rigid fixation for low-grade leaks; and fat graft + NSF ± rigid fixation for high-grade leaks.

Cerebrospinal fluid leaks after transsphenoidal surgery - Effect of a polyethylene glycol hydrogel dural sealant

To investigate cerebrospinal fluid (CSF) leak rates after mainly endoscopic endonasal transsphenoidal surgery with and without polyethylene glycol hydrogel dural sealant (DuraSeal®), we prospectively collected data from a single-centre consecutive case series over four years from January 2007 to December 2010 inclusive. 250 patients were identified (135 male, 115 female; median age 52years, range 14-83). 180 patients received DuraSeal® (72%). 85 (34%) had intra-operative dural breach and 13 (5.2%) developed post-operative CSF leaks (3 without intra-operative dural breach) requiring lumbar drainage or formal repair. Of this group 5/251 (2.0%) patients required a formal repair. Post-operative CSF leak was seen in 5/189 (2.7%) of patients with pituitary adenoma, of which 2/5 (40%) were in cases undergoing revision surgery. 5/13 (38.4%) patients who developed a CSF leak presented with either Rathke's cleft cyst or craniopharyngioma. 3/71 patients not receiving DuraSeal® leaked (4.2%) and 10/180 patients receiving DuraSeal® leaked (5.6%). 11/234 patients without Tisseel (4.7%) and 2/16 receiving Tisseel (12.5%) leaked. 54 patients (22%) received intra-operative lumbar drains, one of whom developed subsequent CSF leak (1.9%), in contrast to 12/197 (6.1%) of patients without intra-operative lumbar drains who later developed CSF leak. The rate of post-operative CSF leak requiring re-exploration and nasoseptal flap repair was low (2.0%) in this mainly endoscopic case series without statistically significant benefit from either DuraSeal® or Tisseel. Intra-operative and post-operative lumbar drainage appears beneficial in patients at higher risk of post-operative CSF leak.

Management of cerebrospinal fluid rhinorrhea: an evidence-based review with recommendations

BACKGROUND

Management strategies employed for cases of cerebrospinal fluid (CSF) rhinorrhea vary widely because of limited evidence-based guidance.

METHODS

A systematic review of the literature was performed using PubMed, EMBASE, and Cochrane databases from January 1990 through September 2014 to examine 5 endoscopic repair techniques and 8 perioperative management strategies for CSF rhinorrhea. Benefit-harm assessments, value judgments, and recommendations were made based on the available evidence. Study exclusion criteria were language other than English, pre-1990 studies, case reports, and nonrhinologic leak. All authors agreed on recommendations through an iterative process.

RESULTS

We reviewed 67 studies examining 13 practices pertinent to the management of CSF rhinorrhea, reaching a highest aggregate grade of evidence of B. The literature does not support the routine use of prophylactic antibiotics or lumbar drainage. Various endoscopic repair materials show similar success rates; however, larger defects may benefit from vascularized grafts. There were no relevant studies to address postoperative activity restrictions.

CONCLUSION

Despite relatively low levels of evidence, recommendations for the management of CSF rhinorrhea can be made based on the current literature. Higher-level studies are needed to better determine optimal clinical management approaches.

Modified Graded Repair of Cerebrospinal Fluid Leaks in Endoscopic Endonasal Transsphenoidal Surgery

OBJECTIVE

Complete sellar floor reconstruction is critical to avoid postoperative cerebrospinal fluid (CSF) leakage during transsphenoidal surgery. Recently, the pedicled nasoseptal flap has undergone many modifications and eventually proved to be valuable and efficient. However, using these nasoseptal flaps in all patients who undergo transsphenoidal surgery, including those who had none or only minor CSF leakage, appears to be overly invasive and time-consuming.

METHODS

Patients undergoing endoscopic endonasal transsphenoidal tumor surgery within a 5 year-period were reviewed. Since 2009, we classified the intraoperative CSF leakage into grades from 0 to 3. Sellar floor reconstruction was tailored to each leak grade. We did not use any tissue grafts such as abdominal fat and did not include any procedures of CSF diversions such as lumbar drainage.

RESULTS

Among 200 cases in 188 patients (147 pituitary adenoma and 41 other pathologies), intraoperative CSF leakage was observed in 27.4% of 197 cases : 14.7% Grade 1, 4.6% Grade 2a, 3.0% Grade 2b, and 5.1% Grade 3. Postoperative CSF leakage was observed in none of the cases. Septal bone buttress was used for Grade 1 to 3 leakages instead of any other foreign materials. Pedicled nasoseptal flap was used for Grades 2b and 3 leakages. Unused septal bones and nasoseptal flaps were repositioned.

CONCLUSION

Modified classification of intraoperative CSF leaks and tailored repair technique in a multilayered fashion using an en-bloc harvested septal bone and vascularized nasoseptal flaps is an effective and reliable method for the prevention of postoperative CSF leaks.

Banked Fascia Lata in Sellar Dura Reconstruction after Endoscopic Transsphenoidal Skull Base Surgery

Objectives Cerebrospinal fluid (CSF) leakage is an undesirable complication of transsphenoidal skull base surgery. The issue of the most appropriate sellar dura repair remains unresolved, although a multilayer technique using autologous fascia lata is widely used. We describe the novel application of a homologous banked fascia lata graft as an alternative to an autologous one in the reconstruction of sellar dura defects in endoscopic transsphenoidal surgery. Design The clinical records of patients who underwent endoscopic transsphenoidal surgery at our department from June 2012, when we started using homologous fascia lata, up to July 2014 were reviewed retrospectively. The data concerning diagnosis, reconstruction technique, and surgical outcome were analyzed. Results We treated 16 patients successfully with banked fascia lata. Twelve patients presented intraoperative CSF leakage, and four patients were treated for postoperative rhinoliquorrhea. Banked fascia lata was used in a single-to-multilayer technique, depending on the anatomical features of the defect and of the sellar floor. No complications or failures in sella reconstruction occurred. Conclusion A banked fascia lata graft proved reliable and safe in providing an effective sellar dura reconstruction. Used in a multilayer strategy, it should be considered a viable alternative to an autologous fascia lata graft.

Pneumocephalus patterns following endonasal endoscopic skull base surgery as predictors of postoperative CSF leaks

OBJECTIVES

Postoperative pneumocephalus is a common occurrence after endoscopic endonasal skull base surgery (ESBS). The risk of cerebrospinal fluid (CSF) leaks can be high and the presence of postoperative pneumocephalus associated with serosanguineous nasal drainage may raise suspicion for a CSF leak. The authors hypothesized that specific patterns of pneumocephalus on postoperative imaging could be predictive of CSF leaks. Identification of these patterns could guide the postoperative management of patients undergoing ESBS.

METHODS

The authors queried a prospectively acquired database of 526 consecutive ESBS cases at a single center between December 1, 2003, and May 31, 2012, and identified 258 patients with an intraoperative CSF leak documented using intrathecal fluorescein. Postoperative CT and MRI scans obtained within 1-10 days were examined and pneumocephalus was graded based on location and amount. A discrete 0-4 scale was used to classify pneumocephalus patterns based on size and morphology. Pneumocephalus was correlated with the surgical approach, histopathological diagnosis, and presence of a postoperative CSF leak.

RESULTS

The mean follow-up duration was 56.7 months. Of the 258 patients, 102 (39.5%) demonstrated pneumocephalus on postoperative imaging. The most frequent location of pneumocephalus was frontal (73 [71.5%] of 102), intraventricular (34 [33.3%]), and convexity (22 [21.6%]). Patients with craniopharyngioma (27 [87%] of 31) and meningioma (23 [68%] of 34) had the highest incidence of postoperative pneumocephalus compared with patients with pituitary adenomas (29 [20.6%] of 141) (p < 0.0001). The incidence of pneumocephalus was higher with transcribriform and transethmoidal approaches (8 of [73%] 11) than with a transsellar approach (9 of [7%] 131). There were 15 (5.8%) of 258 cases of postoperative CSF leak, of which 10 (66.7%) had pneumocephalus, compared with 92 (38%) of 243 patients without a postoperative CSF leak (OR 3.3, p = 0.027). Pneumocephalus located in the convexity, interhemispheric fissure, sellar region, parasellar region, and perimesencephalic region was significantly correlated with a postoperative CSF leak (OR 4.9, p = 0.006) and was therefore termed "suspicious" pneumocephalus. In contrast, frontal or intraventricular pneumocephalus was not correlated with postoperative CSF leak (not significant) and was defined as "benign" pneumocephalus. The amount of convexity pneumocephalus (p = 0.002), interhemispheric pneumocephalus (p = 0.005), and parasellar pneumocephalus (p = 0.007) (determined using a scale score of 0-4) was also significantly related to postoperative CSF leaks. Using a series of permutation-based multivariate analyses, the authors established that a model containing the learning curve, the transclival/transcavernous approach, and the presence of "suspicious" pneumocephalus provides the best overall prediction for postoperative CSF leaks.

CONCLUSIONS

Postoperative pneumocephalus is much more common following extended approaches than following transsellar surgery. Merely the presence of pneumocephalus, particularly in the frontal or intraventricular locations, is not necessarily associated with a postoperative CSF leak. A "suspicious" pattern of air, namely pneumocephalus in the convexity, interhemispheric fissure, sella, parasellar, or perimesencephalic locations, is significantly associated with a postoperative CSF leak. The presence and the score of "suspicious" pneumocephalus on postoperative imaging, in conjunction with the learning curve and the type of endoscopic approach, provide the best predictive model for postoperative CSF leaks.