Case-specific protocol to reduce cerebrospinal fluid leakage after endonasal endoscopic surgery

Visual outcomes in tuberculum sellae meningiomas comparing transcranial and endoscopic endonasal approaches

Background

Tuberculum sellae meningiomas (TSM) account for 3-10% of intracranial meningiomas. Visual loss is the presenting symptom in up to 80% of cases. Surgical management poses a great challenge due to tumor proximity to neurovascular structures such as the optic nerve and the internal carotid artery (ICA); hence, there is controversy regarding the optimal approach. The aim of this study is to determine differences in visual outcomes between transcranial (TCA) and endoscopic endonasal (EEA) approaches.

Methods

A retrospective study including 29 patients with TSM surgically treated by TCA or EEA between 2011 and 2023 in a single referral center was conducted. Pre-and post-operative neuro-ophthalmologic evaluations, focusing on visual acuity and campimetry, were evaluated.

Results

Sixteen (55.16%) patients were intervened through a TCA and the remaining 13 (44.84%) via an EEA. The lesions in each group were similar in terms of pre- operative volume (15.12 vs 12.9 cm3, p = 0.497) and neurovascular invasion (optic canal invasion 48.26 vs 41.37%, p = 0.664; ICA 44.81 vs 31.03%, p = 0.797). There were no significant differences in visual outcomes between both approaches; TCA presented an improvement of 5.18 points in visual fields (p = 0.140), whereas EEA had an improvement of 17.39 points in visual acuity (p = 0.114).

Conclusion

EEA seems to offer greater improvement in visual acuity than TCA. However, the ideal approach should be individualized; taking into account the tumor's volume and invasiveness, as well as the patient's visual complaints.

Diagnostic accuracy of intrathecal fluorescein versus other radiological modalities in evaluating non-congenital skull base defects: a systematic review and meta-analysis

PURPOSE

The intraoperative detection of cerebrospinal fluid (CSF) leaks during endoscopic skull base surgery is critical to ensure watertight sealed defects. Intrathecal fluorescein (ITF) is a valuable adjunct to intraoperative investigation. Hence, our aim is to summarize the evidence of the efficacy of ITF as an accurate diagnostic modality and reconstruction guide for non-congenital skull base defects.

METHODS

Using the Cochrane Central, MEDLINE, and Embase databases, we identified studies involving the use of ITF in non-congenital CSF leaks which were published until November 2023. The STATA 18 software was used for meta-analysis.

RESULTS

Fourteen studies met the inclusion criteria, in which seven studies were included in the meta-analysis. ITF was used in 1898 (90.3%) of patients, with a detection rate of 88.1%. The overall detection rate of non-congenital CSF leaks among ITF concentrations of 5% and 10% had a statistically significant pooled effect size of 2.6 (95% CI = 2.25, 2.95), while when comparing the ITF to other alternative radiological tests, it was not statistically significant with a mean difference of 0.88 (95% CI = - 0.4, 2.16). Moreover, the pooled prevalence was statistically significant in regards of the complications associated with ITF with an effect size of 0.6 (95% CI = 0.39, 0.82), indicating that 60% of patients who underwent ITF would experience at least one of the measured complications.

CONCLUSION

ITF is considered as an efficient tool in localizing skull base defects. However, there was no significant results when comparing the ITF to other alternative radiological tests. Accordingly, if the ITF intervention is indicated, patients should be carefully selected based on their clinical need.

Fat in the Fossa and the Sphenoid Sinus: A Simple and Effective Solution to CSF Leaks in Transsphenoidal Surgery. Cohort Study and Systematic Review

Objectives  Cerebrospinal fluid (CSF) leak following endoscopic transsphenoidal surgery (TSS) remains a challenge and is associated with high morbidity. We perform a primary repair with f at in the pituitary f ossa and further fat in the s phenoid sinus (FFS). We compare the efficacy of this FFS technique with other repair methods and perform a systematic review. Design, Patients, and Methods  This is a retrospective analysis of patients undergoing standard TSS from 2009 to 2020, comparing the incidence of significant postoperative CSF rhinorrhea (requiring intervention) using the FFS technique compared with other intraoperative repair strategies. Systematic review of current repair methods described in the literature was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Results  In all, there were 439 patients, with 276 patients undergoing multilayer repair, 68 patients FFS repair, and 95 patients no repair. No significant differences were observed in baseline demographics between the groups. Postoperative CSF leak requiring intervention was significantly lower in the FFS repair group (4.4%) compared with the multilayer (20.3%) and no repair groups (12.6%, p  < 0.01). This translated to fewer reoperations (2.9% FFS vs. 13.4% multilayer vs. 8.4% no repair, p  < 0.05), fewer lumbar drains (2.9% FFS vs. 15.6% multilayer vs. 5.3% no repair, p  < 0.01), and shorter hospital stay (median days: 4 [3-7] FFS vs. 6 (5-10) multilayer vs. 5 (3-7) no repair, p  < 0.01). Risk factors for postoperative leak included female gender, perioperative lumbar drain, and intraoperative leak. Conclusion  Autologous fat on fat graft for standard endoscopic transsphenoidal approach effectively reduces the risk of significant postoperative CSF leak with reduced reoperation and shorter hospital stay.

Evaluating the Efficacy of Topical Intranasal Fluorescein for Localizing CSF Rhinorrhea: A Systematic Review

OBJECTIVE

To assess existing literature on topical intranasal fluorescein (TINF) for the diagnosis and localization of nasal cerebrospinal fluid (CSF).

STUDY DESIGN

Systematic review.

METHODS

A 6-database literature search was conducted to identify articles providing insight into TINF for the diagnosis and treatment of sinonasal CSF leak. Demographic characteristics, technical details, efficacy, and safety data were extracted and analyzed. Methodological quality was assessed using Methodological Items for Non-Randomized Studies (MINORS) criteria.

RESULTS

All studies reported a diagnostic accuracy rate ≥96%. There were no major complications reported for any patient (n=99) with either 5% or 10% fluorescein use. The MINORS instrument of methodological quality indicated that the assessed studies were of moderate quality (7.29 out of a maximum score of 24).

CONCLUSION

This systematic review indicates that TINF is an easy, safe, inexpensive, and sensitive approach for the diagnosis and treatment of sinonasal CSF leakage. For these reasons, it may be especially well suited for resource-limited clinical scenarios.

Closure strategy for endoscopic pituitary surgery: Experience from 3015 patients

Introduction

Effective strategies are required to ensure optimal management of the crucial closure step in endoscopic pituitary surgery. Many surgical techniques have been reported but no significant consensus has been defined.

Methods

Between January 2006 and March 2022, 3015 adult patients with pituitary adenomas were operated on by a single expert neurosurgical team, using a mononostril endoscopic endonasal approach. Based of preoperative risk factors of and operative findings, a detailed closure strategy was used. Body mass index >40, sellar floor lysis, number of surgeries>2, large skull base destruction, prior radiotherapy were considered as preoperative risk factors for closure failure. All patients treated with an expanded endonasal approach were excluded.

Results

Patients were mostly women (F/M ratio: 1.4) with a median age of 50 (range: 18 -89). Intraoperative CSF leak requiring specific surgical management was observed in 319/3015 (10.6%) of patients. If intraoperative leak occurred, patients with predictive risk factors were managed using a Foley balloon catheter in case of sellar floor lysis or BMI>40 and a multilayer repair strategy with a vascularized nasoseptal flap in other cases. Postoperative CSF leak occurred in 29/3015 (1%) of patients, while meningitis occurred in 24/3015 (0.8%) of patients. In patients with intraoperative leak, closure management failed in 11/319 (3.4%) of cases.

Conclusion

Based on our significant 16-year experience, our surgical management is reliable and easy to follow. With a planned and stepwise strategy, the closure step can be optimized and tailored to each patient with a very low failure rate.

Endonasal transsphenoidal surgery for planum sphenoidale versus tuberculum sellae meningiomas

OBJECTIVE

The aim of this study was to determine if the distinction between planum sphenoidale (PS) and tuberculum sellae (TS) meningiomas is clinically meaningful and impacts the results of the endoscopic endonasal approach (EEA).

METHODS

A consecutive series of patients who were 18 years of age or older and underwent EEA for newly diagnosed grade I PS meningiomas (PSMs) and TS meningiomas (TSMs) between October 2007 and May 2021 were included. The PS and TS were distinguished by drawing a line passing through the center of the TS and perpendicular to the PS on postcontrast T1-weighted MRI. Probabilistic heatmaps were created to display the actual distribution of tumor volumes. Tumor volume, extent of resection (EOR), visual outcome, and complications were assessed.

RESULTS

The 47 tumors were distributed in a smooth continuum. Using an arbitrary definition, 24 (51%) were PSMs and 23 (49%) were TSMs. The mean volume of PSMs was 5.6 cm3 compared with 4.5 cm3 for TSMs. Canal invasion was present in 87.5% of PSMs and 52% of TSMs. GTR was achieved in 38 (84%) of 45 cases in which it was the goal, slightly less frequently for PSMs (78%) compared with TSMs (91%), although the difference was not significant. Th mean EOR was 99% ± 2% for PSMs and 98% ± 11% for TSMs. Neither the suprasellar notch angle nor the percentage of tumor above the PS impacted the rate of GTR. After a median follow-up of 28.5 months (range 0.1–131 months), there were 2 (5%) recurrences after GTR (n = 38) both of which occurred in patients with PSMs. Forty-two (89%) patients presented with preoperative impaired vision. Postoperative vision was stable or improved in 96% of patients with PSMs and 91% of patients with TSMs. CSF leakage occurred in 4 (16.6%) patients with a PSM, which resolved with only lumbar drainage, and in 1 (4.3%) patient with a TSM, which required reoperation.

CONCLUSIONS

PSM and TSMs arise in a smooth distribution, making the distinction arbitrary. Those classified as PSMs were larger and more likely to invade the optic canals. Surgical outcome for both locations was similar, slightly favoring TSMs. The arbitrary distinction between PSMs and TSMs is less useful at predicting outcome than the lateral extent of the tumor, regardless of the site of origin.

The critical importance of a vascularized flap in preventing recurrence after endoscopic repair of spontaneous cerebrospinal fluid leaks and meningoencephaloceles

OBJECTIVE

Spontaneous CSF leaks into the anterior skull base nasal sinuses are often associated with meningoencephaloceles and occur in patients with idiopathic intracranial hypertension (IIH). Endonasal endoscopic repair has become the primary method of choice for repair. The authors sought to evaluate the success rate of endoscopic closure and to identify predictive factors for CSF leak recurrence.

METHODS

A consecutive series of endonasally repaired anterior skull base meningoencephaloceles was drawn from a prospectively acquired database. Lumbar punctures were not performed as part of a treatment algorithm. All patients had at least 5 months of follow-up. Chart review and phone calls were used to determine the timing and predictors of recurrence. Demographic information and details of operative technique were correlated with recurrence. Two independent radiologists reviewed all preoperative imaging to identify radiographic markers of IIH, as well as the location and size of the meningoencephalocele.

RESULTS

From a total of 54 patients there were 5 with recurrences (9.3%), but of the 39 patients in whom a vascularized nasoseptal (n = 31) or turbinate (n = 8) flap was used there were no recurrences (p = 0.0009). The mean time to recurrence was 24.8 months (range 9-38 months). There was a trend to higher BMI in patients whose leak recurred (mean [± SD] 36.6 ± 8.6) compared with those whose leak did not recur (31.8 ± 7.4; p = 0.182). Although the lateral recess of the sphenoid sinus was the most common site of meningoencephalocele, the fovea ethmoidalis was the most common site in recurrent cases (80%; p = 0.013). However, a vascularized flap was used in significantly more patients with sphenoid (78.3%) defects than in patients with fovea ethmoidalis (28.6%) defects (Fisher's exact test, p = 0.005). Radiographic signs of IIH were equally present in all patients whose leak recurred (75%) compared with patients whose leak did not recur (63.3%); however, an enlarged Meckel cave was present in 100% (2/2) of patients whose leaks recurred compared with 13.3% (4/30) of patients whose leaks did not recur (p = 0.03). The average meningoencephalocele diameter tended to be larger (1.73 ± 1.3 cm) in patients with recurrence compared to those without recurrence (1.2 ± 0.66 cm; p = 0.22). A ventriculoperitoneal shunt was already in place in 3 patients, placed perioperatively in 5, and placed at recurrence in 2, none of whose leaks recurred.

CONCLUSIONS

Recurrence after endonasal repair of spontaneous CSF leaks from meningoencephaloceles can be dramatically reduced with the use of a vascularized flap. Although failures of endonasal repair tend to occur in patients who have higher BMI, larger brain herniations, and no CSF diversion, the lack of vascularized flap was the single most important risk factor predictive of failure.

Pediatric pituitary adenomas are more aggressive, more likely to be hormone producing and are more difficult to cure than adult pituitary adenomas: case series and systematic literature review

PURPOSE

Pediatric pituitary adenomas (pPAs) are uncommon. Thus, their presentation and outcomes after treatment are less well-understood than those of pituitary adenomas in adulthood (aPAs).

METHODS

A retrospective chart review was conducted for all patients who underwent endoscopic endonasal transsphenoidal surgery (EETS) for pPA at NewYork-Presbyterian Hospital/Weill Cornell Medicine (NYP/WCM) from 2005-2020. Eleven patients were identified, and information pertaining to age, sex, adenoma characteristics, procedural details, and outcomes was reviewed. A systematic review of the literature was also performed to compare outcomes of EETS versus microscopic endonasal transsphenoidal surgery (METS) for pPA.

RESULTS

From 2005-2020, 11 patients underwent EETS for pPA at NYP/WCM. Mean age at operation was 14.9 ± 2.7 years, and 5 patients (45.5%) were male. 10 adenomas (90.9%) were hormone-producing. Of the functional adenomas, 8 (80.0%) were PRL-secreting and 2 (20.0%) were GH-secreting. Maximum adenoma diameter (MAD) ranged from 1.2-5.1 cm, with a median of 1.55 cm. Cavernous sinus invasion (CSI) occurred in 2 patients with macroprolactinoma. Gross total resection (GTR) was achieved in 10 (90.9%). Biochemical remission occurred in 5/10 (50.0%). Post-operative complications were documented in 8 cases (72.7%) and included diabetes insipidus, hypopituitarism, sinusitis, weight gain, cerebrospinal fluid leak, meningitis, and hydrocephalus. Systematic literature review of 105 microscopic and 175 endoscopic cases revealed high frequency of hormone-producing tumors (83.6%) and similar rates of GTR (82.4% vs 85.1%) and biochemical cure (75.8% vs 64.3%).

CONCLUSIONS

pPAs are more likely to be hormone producing and may be more aggressive and difficult to cure than aPAs. EETS is an effective treatment, although complication rates may be higher than in adult populations.

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.

Endonasal Endoscopic Fenestration of Rathke's Cleft Cysts: Whether to Leave the Fenestration Open or Closed?

Introduction  Rathke's cleft cysts (RCC) are generally treated with transsphenoidal fenestration and cyst drainage. If no cerebrospinal fluid (CSF) leak is created, the fenestration can be left open. If CSF is encountered, a watertight closure must be created to prevent postoperative CSF leak, though sellar closure has theoretically been linked with higher recurrence rate. In this study, we investigate the relationship between sellar closure, rate of postoperative CSF leak, and RCC recurrence. Methods  Retrospective review of a prospective database of all endoscopic endonasal RCC fenestrations and cases were divided based on closure. The "open" group included patients who underwent fenestration of the RCC, whereas the "closed" group included patients whose RCC was treated with fat and a rigid buttress ± a nasoseptal flap. The rate of intra- and postoperative CSF leak and radiographic recurrence was determined. Results  The closed group had a higher rate of suprasellar extension (odds ratio [OR]: 8.0, p  = 0.032) and intraoperative CSF leak ( p ≤ 0.001). There were 54.8% intraoperative CSF leaks and no postoperative CSF leaks. Radiologic recurrence rate for the closed group (35.0%) was three times higher than the open group (9.1%; risk ratio [RR] = 3.85, p  = 0.203), but not powered to show significance. None of the radiologic recurrences required reoperation. Conclusion  Maintaining a patent fenestration between an RCC and the sphenoid sinus is important in reducing the rate of radiographic recurrence. Closure of the fenestration may be required to prevent CSF leak. While closure increases the rate of radiographic recurrence, reoperation for recurrent RCC is still an uncommon event.

Closure of skull base defects after endoscopic endonasal transsphenoidal surgery: the role of the local sphenoid mucosal flap for low flow leaks

A local sphenoid mucosal flap (SMF) is naturally raised during endonasal exposure of the sella. Typically, these flaps are repositioned; however, they could be used in place of a nasoseptal flap (NSF) for closure of low-grade CSF leaks. In this study, we aim to establish the safety and efficacy of SMF closure for low-grade CSF leaks and to assess the impact on sinonasal quality of life (QoL) compared to NSF closure. In a consecutive, prospective cohort of anterior skull base pathology, data regarding sellar and suprasellar extension (Hardy grade), cavernous sinus invasion (Knosp grade), intraoperative (Kelly grade) and postoperative CSF leak, and sino-nasal QoL data (SNOT-22) were analysed. Of 187 patients with no/low flow (Kelly 0-1) intraoperative CSF leak, 127 (67.9%) received a SMF and 60 (32.1%) received a NSF. A total of 141/187 (75.4%) had no intraoperative leak, while 46/187 (24.6%) had grade-1 leaks. SMF were used in 70.9% (100/141) of cases without intraoperative leak, and 58.7% (27/46) of cases with Kelly grade-1 leaks. Hardy grade 4, grade E and Knosp grade 4 lesions were all more commonly closed with a NSF (p < 0.05). Two patients (1.1%) had postoperative CSF leaks, both in the SMF group, and both after no discernible intraoperative leak. Sinonasal QoL was below baseline for up to 3 months postoperatively. SMF cases tended to have better sinonasal QoL for up to 6 weeks after surgery. Thus, in the largest cohort to date, SMF are a safe alternative to NSF for closure low-grade skull base defects. Sinonasal QoL was better in the first 6 weeks after SMF closure than NSF closure.

Endoscopic endonasal approach for craniopharyngiomas

The operative management of craniopharyngiomas has evolved over the last two decades. Traditional transcranial microsurgical approaches were the only option until the advent of the endoscopic endonasal approach. It has given surgeons the ability to tackle a challenging entity from a new perspective with comparable if not superior results. In this review we outline the advancements in endoscopic endonasal approach for craniopharyngiomas, address controversies and review the current literature.

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.

Aggressive resection of craniopharyngioma achieved by drilling the tuberculum sellae/planum sphenoidale using a frontal basal interhemispheric approach: A review of 55 cases

OBJECTIVE

The frontal basal interhemispheric approach (FBIA) is preferable for resection of craniopharyngioma (CP), achieving desirable total resection rates in early reports of lesions located in the suprasellar region to the third ventricle. For tumours that have created a larger obstruction of the tuberculum sellae and planum sphenoidale, aggressive resection in the intrasellar region and medial wall of the cavernous sinus is not feasible compared to improving tumour visualization by drilling the tuberculum sellae and planum sphenoidale. In a report of drilling the sellar tuberculum and sphenoid planum, drilling allowed the direct visualization of tumours invading the intrasellar region and medial wall of the cavernous sinus. Reconstructing the opening of the sellar-sphenoid cavity is achieved by microsuturing a piece of the pericranium/dura around the dural edge of the defective dura of the open sphenoid sinus and sellar cavity to prevent cerebrospinal fluid (CSF) leakage.

PATIENTS AND METHODS

The FBIA with drilling of the tuberculum sellae and planum sphenoidale was performed to remove the tumours that invaded the intrasellar region and cavernous sinus in 55 patients from January 2014 to October 2019 at our institution. The pre- and postoperative pituitary hormone levels and vision were evaluated as effective standards after surgery and compared using paired t-tests. The different rates of CSF leakage between the packing and microsuture groups were compared by χ² test, p < 0.05.

RESULTS

In all patients with a mean 37-month follow-up (range, 3-2 months), 43 (78.2%) patients returned to their normal life or school independently, 7 (12.7%) patients were able to perform normal activities with minor complaints or effort, and 4 (7.3%) patients could care for themselves or only required occasional assistance. One (1.8%) death occurred, attributed to CSF leak-related meningitis at 5 months after surgery. Postoperative CSF leakage occurred in eight (19.0%) of 42 patients with packed bone wax or pieces of muscle to the sphenoid sinus. Of 13 patients with a piece of the periosteum/dura microsutured around the defective dura of the sellar region and open sphenoid sinus, one (7.7%) of 13 patients experienced CSF leakage in the perioperative period. With statistical analysis, there was a potential risk for postoperative CSF leakage in the bone wax and muscle piece in the open sphenoid sinus, whereas microsuture manoeuvres were effective for avoiding the risk of postoperative CSF leakage (χ² = 8.865, p < 0.005). The microsutures closed the open sphenoid sinus such that it was water-tight. Postoperative visual acuity and the visual field were not affected by the increased intrasellar exposure or the open sphenoid sinus achieved by drilling the tuberculum sellae and planum sphenoidale.

CONCLUSION

Tuberculum sellae/planum sphenoidale drilling via FBIA is feasible to enhance the direct visualization of CP resection, which expands the intrasellar region with a direct resection of recurrent tumours in the sellar cavity and adhering to the medial wall of the cavernous sinus. The potential risk of a CSF leakage seemed to be mitigated when using water-tight microsutures on a piece of the pericranium/dura around the edge of the defective dura in the sellar region and the open sphenoid sinus cavity.

The Umbrella Technique for the Closure of Cerebrospinal Fluid Fistula

ABSTRACT

The diagnosis and management of cerebrospinal fluid (CSF) rhinorrhea remains an important challenge in the field of rhinology. In this study, the authors want to propose a technique for transnasal endoscopic closure of CSF fistulas, tested for the first time on 2 adult fresh cadaveric specimens. The authors think that the use of a device similar to the umbrella device, used to close cardiac atrial defects, may also be valid for the closure of defects at the level of the anterior skull base.

Endoscopic endonasal approach for suprasellar meningiomas: introduction of a new scoring system to predict extent of resection and assist in case selection with long-term outcome data

OBJECTIVE

The endoscopic endonasal approach (EEA) has gained increasing popularity for the resection of suprasellar meningiomas (SSMs). Appropriate case selection is critical in optimizing patient outcome. Long-term outcome data are lacking. The authors systematically identified preoperative factors associated with extent of resection (EOR) and determined the relationship between EOR and long-term recurrence after EEA for SSMs.

METHODS

In this retrospective cohort study, the authors identified preoperative clinical and imaging characteristics associated with EOR and built on the recently published University of California, San Francisco resectability score to propose a score more specific to the EEA. They then examined the relationship between gross-total resection (GTR; 100%), near-total resection (NTR; 95%-99%), and subtotal resection (STR; < 95%) and recurrence or progression with Kaplan-Meier survival analysis.

RESULTS

A total of 51 patients were identified. Radiographic GTR was achieved in 40 of 47 (85%) patients in whom it was the surgical goal. Significant independent risk factors for incomplete resection were prior surgery (OR 25.94, 95% CI < 2.00 to 336.49, p = 0.013); tumor lateral to the optic nerve (OR 13.41, 95% CI 1.82-98.99, p = 0.011); and complete internal carotid artery (ICA) encasement (OR 15.12, 95% CI 1.17-194.08, p = 0.037). Tumor size and optic canal invasion were not significant risk factors after adjustment for other variables. A resectability score based on the multivariable model successfully predicted the likelihood of GTR; a score of 0 had a positive predictive value of 97% for GTR, whereas a score of 2 had a negative predictive value of 87.5% for incomplete resection. After a mean follow-up of 40.6 ± 32.4 months (mean ± SD), recurrence was 2.7% after GTR (1 patient with atypical histology), 44.4% after NTR, and 80% after STR (p < 0.0001). Vision was stable or improved in 93.5% and improved in 67.4% of patients with a preoperative deficit. There were 5 (9.8%) postoperative CSF leaks, of which 4 were managed with lumbar drains and 1 required a reoperation.

CONCLUSIONS

The EEA is a safe and effective approach to SSMs, with favorable visual outcomes in well-selected cases. The combination of postoperative MRI-based EOR with direct endoscopic inspection can be used in lieu of Simpson grade to predict recurrence. GTR dramatically reduces recurrence and can be achieved regardless of tumor size, proximity or encasement of the anterior cerebral artery, or medial optic canal invasion. Risk factors for incomplete resection include prior surgery, tumor lateral to the optic nerve, and complete ICA encasement.

Diabetes insipidus and syndrome of inappropriate antidiuresis (SIADH) after pituitary surgery: incidence and risk factors

Electrolyte disorders are relatively frequent and potentially serious complications after pituitary surgery. Both DI (diabetes insipidus) and SIADH (syndrome of inappropriate antidiuresis) can complicate and prolong hospital and intensive care unit stay, and the latter may even be preventable. We aim to assess the incidence of both electrolyte disorders and their risk factors. From a prospective registry of patients who underwent endoscopic transnasal transsphenoidal surgery (TSS) for pituitary adenoma, patients with postoperative DI and SIADH were identified. Univariable and multivariable statistics were carried out to identify factors independently associated with the occurrence of either DI or SIADH. A total of 174 patients were included, of which 73 (42%) were female. Mean age was 54 years (range 20-88). During postoperative hospital stay, 13 (7.5%) patients presenting with DI and 11 (6.3%) with SIADH were identified. Patients who developed DI after surgery had significantly longer hospital stays (p = 0.022), as did those who developed SIADH (p = 0.002). Four (2.3%) patients were discharged with a diagnosis of persistent DI, and 2 (1.1%) with the diagnosis of SIADH. At the last follow-up, 5 (2.9%) patients presented with persistent DI, while none of the patients suffered from SIADH. Younger age (odds ratio (OR) 0.97, 95% confidence interval (CI) 0.94-1.01, p = 0.166) and pituitary apoplexy (OR 2.69, 95% CI 0.53-10.65, p = 0.184) were weakly associated with the occurrence of DI. We identified younger age (OR 0.96, 95% CI 0.92-0.99, p = 0.045) and lower preoperative serum sodium (OR 0.83, 95% CI 0.71-0.95, p = 0.008) as independent risk factors for SIADH. Although we found a weak association among age, pituitary apoplexy, and the occurrence of DI, no independent predictor was identified for DI. For postoperative SIADH however, lower age and preoperative serum sodium were identified as significant predictors. None of these findings were sufficiently supported by preexisting literature. Both electrolyte disorders are exquisitely hard to predict preoperatively, and further research into their early detection and prevention is warranted.

TRANS-FRONTAL SINUS APPROACH FOR OLFACTORY GROOVE MENINGIOMAS: A 19 YEAR EXPERIENCE

INTRODUCTION

Olfactory groove meningiomas (OGMs) account for 8-13 % of all intracranial meningiomas. The gold standard of treatment is generally surgery, however various approaches have been used and the literature is still uncertain about the superiority of one treatment over the others. The most debated techniques are traditional microscopic open approaches versus the endoscopic endonasal ones. The aim of this paper is to prove a valid surgical route that gathers the benefits of both endoscopic and transcranial routes.

METHODS

Fifty consecutive patients underwent trans-frontal sinus surgical removal of an OGM between January 2000 and January 2019 at the Neurosurgical Departments in Torino, Brescia and Legnano (Italy). The clinical features were collected in a database and compared with neuroimaging and outcomes. All patients were investigated with neuroimaging techniques. Clinical evaluations were performed 3-4 months and 1 year after surgery, together with neuroradiological follow-up.

RESULTS

All patients with OGM underwent Simpson grade I resection. The most common neurological symptom leading to neuroradiological evaluations were headaches (36 %), followed by behavioural changes (30 %), hyposmia/anosmia (12 %), visual impairments (6%) and focal deficits (6%). At 3-4 months follow-up 48 patients underwent a brain MRI (2 patients underwent a brain CT), and a complete resection was confirmed in 45 patients (94 %).

CONCLUSIONS

Despite different techniques and studies supported by good evidence, there is no consensus on the best surgical approach for OGMs. The data shown in this article suggests that the trans-frontal sinus approach is a valid alternative to an endoscopic approach and the classical transcranial routes, collecting benefits from both approaches.

Acellular dermal matrix as an alternative to autologous fascia lata for skull base repair following extended endoscopic endonasal approaches

BACKGROUND

Skull base reconstruction after extended endoscopic endonasal approaches (EEAs) can be challenging. In addition to the nasoseptal flap, which has been adopted by most centers, autologous fascia lata is also often utilized. Harvesting of fascia lata requires a separate thigh incision, may prolong recovery, and results in a visible scar. In principal, the use of non-autologous materials would be preferable to avoid a second incision and maintain the minimally invasive nature of the approach, assuming the CSF leak rate is not compromised.

OBJECTIVE

To assess the efficacy of acellular dermal matrix (ADM) as a non-autologous alternative to autologous fascia lata graft for watertight closure of the cranial base following EEAs.

METHODS

A retrospective chart review of extended EEAs performed before and after the transition from fascia lata to ADM was performed. Cases were frequency matched for approach, pathology, BMI, use of lumbar drainage, and tumor volume. Power analysis was performed to estimate the sample size needed to demonstrate non-inferiority.

RESULTS

ADM was used for watertight closure of the cranial base in 19 consecutive extended endoscopic endonasal approaches (16 gasket-seals and 3 buttons) with 1 postoperative CSF leak at the last follow-up (median 5.3, range 1.0-12.6 months). All patients had high-flow intraoperative leaks. The cohort included 8 meningiomas, 8 craniopharyngiomas, 2 chordomas, and 1 pituicytoma ranging in size from 0.2 to 37.2cm³ (median 5.5, IQR 2.8-13.3 cm³). In 19 historical controls who received fascia lata, there were 2 postoperative CSF leaks.

CONCLUSIONS

Preliminary results suggest that ADM provides a non-inferior non-autologous alternative to fascia lata for watertight gasket-seal and button closures following extended EEAs, potentially reducing or eliminating the need to harvest autologous tissue.

How long is the tail end of the learning curve? Results from 1000 consecutive endoscopic endonasal skull base cases following the initial 200 cases

OBJECTIVE

Endoscopic endonasal approaches (EEAs) to the skull base have evolved over the last 20 years to become an essential component of a comprehensive skull base practice. Many case series show a learning curve from the earliest cases, in which the authors were inexperienced or were not using advanced closure techniques. It is generally accepted that once this learning curve is achieved, a plateau is reached with little incremental improvement. Cases performed during the early steep learning curve were eliminated to examine whether the continued improvement exists over the "tail end" of the curve.

METHODS

A prospectively acquired database of all EEA cases performed by the senior authors at Weill Cornell Medicine/NewYork-Presbyterian Hospital was reviewed. The first 200 cases were eliminated and the next 1000 consecutive cases were examined to avoid the bias created by the early learning curve.

RESULTS

Of the 1000 cases, the most common pathologies included pituitary adenoma (51%), meningoencephalocele or CSF leak repair (8.6%), meningioma (8.4%), craniopharyngioma (7.3%), basilar invagination (3.1%), Rathke's cleft cyst (2.8%), and chordoma (2.4%). Use of lumbar drains decreased from the first half to the second half of our series (p <0.05) as did the authors' use of fat alone (p <0.005) or gasket alone (p <0.005) for dural closure, while the use of a nasoseptal flap increased (p <0.005). Although mean tumor diameter was constant (on average), gross-total resection (GTR) increased from 60% in the first half to 73% in the second half (p <0.005). GTR increased for all pathologies but most significantly for chordoma (56% vs 100%, p <0.05), craniopharyngioma (47% vs 0.71%, p <0.05) and pituitary adenoma (67% vs 75%, p <0.05). Hormonal cure for secreting adenomas also increased from 83% in the first half to 89% in the second half (p <0.05). The rate of any complication was unchanged at 6.4% in the first half and 6.2% in the latter half of cases, and vascular injury occurred in only 0.6% of cases. Postoperative CSF leak occurred in 2% of cases and was unchanged between the first and second half of the series.

CONCLUSIONS

This study demonstrates that contrary to popular belief, the surgical learning curve does not plateau but can continue for several years depending on the complexity of the endpoints considered. These findings may have implications for clinical trial design, surgical education, and patient safety measures.

Patient Wellbeing and Quality of Life After Nasoseptal Flap Closure for Endoscopic Skull Base Reconstruction

BACKGROUND

The endoscopic endonasal approach to the skull base avoids some of the surgical morbidity associated with a transcranial approach, however it often results in large skull-base defects requiring secure closure. The nasoseptal flap has become the preferred method for closure of such defects but may be associated with its own morbidity.

METHODS

A consecutive cohort of patients with skull base pathology with prospectively collected quality of life data using ASBQ and SNOT was analysed. They were grouped into those who received a nasoseptal flap and those who did not. Pre-operative total ASBQ and SNOT scores, and their individual components, were compared to data collected at days 1, 3, and 7; six-weeks; and 3, 6, and 12-months postoperatively.

RESULTS

Of 158 patients available for analysis, nasoseptal flaps were performed in 52 (33%). Average follow-up (±standard deviation) was 8.1 ± 3.9 months for ASBQ data and 8.2 ± 3.8 months for SNOT data. In the first post-operative week, nasal symptoms and otalgia were worse in the flap group. At six-weeks and beyond, there was no difference between groups in overall ASBQ or SNOT scores, or in the rate of clinically-significant improvement in SNOT or ASBQ scores or their components.

CONCLUSION

In the largest cohort of patients to date, the use of a nasoseptal flap is associated with nasal symptoms and otalgia in the acute post-operative period, but is not associated with any long-term detriment to quality of life after endoscopic skull base surgery.

Correlation of spontaneous and traumatic anterior skull base CSF leak flow rates with fluid pattern on early, delayed, and subtraction volumetric extended echo train T2-weighted MRI

OBJECTIVE

CSF leakage is a potentially fatal condition that may result when a skull base dural defect permits CSF communication between the cranial vault and sinonasal cavities. Flow rate is an important property of CSF leaks that can contribute to surgical decision-making and predispose patients to complications and inferior outcomes. Noninvasive preoperative prediction of the leak rate is challenging with traditional diagnostic tools. The present study compares fluid configurations on early and late volumetric extended echo train T2-weighted MRI by using image tracings and sequence subtraction as a novel method of quantifying CSF flow rate, and it correlates radiological results with intraoperative findings and clinical outcomes.

METHODS

A total of 45 patients met inclusion criteria for this study and underwent 3-T MRI. Imaging sequences included two identical CUBE T2 (vendor trade name for volumetric extended echo train T2) acquisitions at the beginning and end of the scanning session, approximately 45 minutes apart. Twenty-five patients were confirmed to have definitive spontaneous or traumatic anterior skull base CSF leaks. Semiautomated volumetric segmentation of CSF intensity was performed on both CUBE data sets by using 3D-Slicer software, and volumes were subtracted to obtain accumulated CSF volume. These imaging-derived fluid accumulations were correlated with high- or low-flow states, as well as ultimate treatment outcomes including recurrences.

RESULTS

Of the 45 patients, 25 (55.6%) had definitive evidence of CSF leakage, and 22 (88%) of these underwent surgical repair. Patients with high-flow CSF leaks had higher early (4.058 cm3 vs 0.982 cm3, p = 0.04), late (4.58 cm3 vs 1.096 cm3, p = 0.04), and accumulated (0.53 cm3 vs 0.11 cm3, p = 0.01) fluid volume measurements than patients with low-flow leaks. The 5 (22.7%) patients who exhibited postoperative CSF leak recurrence had significantly greater early (6.30 cm3 vs 1.23 cm3, p = 0.008) and late (6.87 cm3 vs 1.45 cm3, p = 0.008) volumes. Accumulated volume was not significantly greater in patients with leak recurrence (0.58 cm3 vs 0.22 cm3, p = 0.07). Early, late, and accumulated volumes were significantly correlated with postoperative hospital stay as well as duration of postoperative lumbar drain placement (p < 0.05 for all measures).

CONCLUSIONS

High-resolution CUBE T2 MRI, coupled with precise volumetric segmentation and subtraction of sinonasal hyperintensity, not only demonstrated predictive value in differentiating low- and high-flow CSF leaks, but also correlated with postoperative complications such as leak recurrence. These findings may be useful in the clinical workup and neurosurgical management of patients with skull base CSF leaks.

Three-Hand Endoscopic Endonasal Transsphenoidal Surgery: Experience With an Anatomy-Preserving Mononostril Approach Technique

BACKGROUND

Variations on the endoscopic transsphenoidal approach present unique surgical techniques that have unique effects on surgical outcomes, extent of resection (EOR), and anatomical complications.

OBJECTIVE

To analyze the learning curve and perioperative outcomes of the 3-hand endoscopic endonasal mononostril transsphenoidal technique.

METHODS

Prospective case series and retrospective data analysis of patients who were treated with the 3-hand transsphenoidal technique between January 2007 and May 2015 by a single neurosurgeon. Patient characteristics, preoperative presentation, tumor characteristics, operative times, learning curve, and postoperative outcomes were analyzed. Volumetric EOR was evaluated, and a logistic regression analysis was used to assess predictors of EOR.

RESULTS

Two hundred seventy-five patients underwent an endoscopic transsphenoidal surgery using the 3-hand technique. One hundred eighteen patients in the early group had surgery between 2007 and 2010, while 157 patients in the late group had surgery between 2011 and 2015. Operative time was significantly shorter in the late group (161.6 min) compared to the early group (211.3 min, P = .001). Both cohorts had similar EOR (early group 84.6% vs late group 85.5%, P = .846) and postoperative outcomes. The learning curve showed that it took 54 cases to achieve operative proficiency with the 3-handed technique. Multivariate modeling suggested that prior resections and preoperative tumor size are important predictors for EOR.

CONCLUSION

We describe a 3-hand, mononostril endoscopic transsphenoidal technique performed by a single neurosurgeon that has minimal anatomic distortion and postoperative complications. During the learning curve of this technique, operative time can significantly decrease, while EOR, postoperative outcomes, and complications are not jeopardized.

Proposal of Standardization of Closure Techniques After Endoscopic Pituitary and Skull Base Surgery Based on Postoperative Cerebrospinal Fluid Leak Risk Classification

Postoperative cerebrospinal fluid (CSF) leak still represents the main limitation of endonasal endoscopic surgery. The aim of the study is to classify the risk of postoperative leak and to propose a decision-making protocol to be applied in the preoperative phase based on radiological data and on intraoperative findings to obtain the best closure.One hundred fifty-two patients were treated in our institution; these patients were divided into 2 groups because from January 2013 the closure technique was standardized adopting a preoperative decision-making protocol. The Postoperative CSF leak Risk Classification (PCRC) was estimated taking into account the size of the lesion, the extent of the osteodural defect, and the presence of intraoperative CSF leak (iCSF-L). The closure techniques were classified into 3 types according to PCRC estimation (A, B, and C).The incidence of the use of a nasoseptal flap is significantly increased in the second group 80.3% versus 19.8% of the first group and the difference was statistically significant P < 0.0001. The incidence of postoperative CSF leak (pCSF-L) in the first group was 9.3%. The incidence of postoperative pCSF-L in the second group was 1.5%. An analysis of the pCSF-L rate in the 2 groups showed a statistically significant difference P = 0.04.The type of closure programmed was effective in almost all patients, allowing to avoid the possibility of a CSF leak. Our protocol showed a significant total reduction in the incidence of CSF leak, but especially in that subgroup of patients where a leak is usually unexpected.

Adherus Dural Sealant in Endoscopic Skull Base Surgery: Safety, Imaging Characteristics, and Sinonasal Quality of Life

Objective  This study was aimed to compare the safety profiles, magnetic resonance imaging (MRI) findings, and sinonasal outcome test (SNOT-22) scores of Adherus dural sealant, a novel tissue glue designed for skull base surgery. Design  Present study is a prospective case series. Setting  The research work took place at a tertiary-care academic medical center. Participants  Consecutive series of 26 patients undergoing endoscopic skull base surgery (ESBS) with Adherus was compared with a control group of 24 patients matched for tumor type and size with DuraSeal as a sealant. Main Outcome Measures  Postoperative complication rates, imaging characteristics, and postoperative SNOT-22 scores were measured and compared. Results  No postoperative cerebrospinal fluid (CSF) leaks, intracranial hemorrhages, or mucoceles were observed in either cohort. Adherus was more likely to be identifiable on immediate postoperative MRI (50 vs. 20.8%, p  = 0.032). In patients in whom a nasoseptal flap was utilized, the flap was opposed to the skull base in all cases regardless of sealant selected. Postoperative SNOT-22 total (17.25 [±10.81] vs. 14.85 [±14.22], p  = 0.609) and subdomain scores were similar between the two groups. Conclusions  Adherus dural sealant appears to be a safe alternative to Duraseal in ESBS with comparable quality of life outcomes and imaging findings. These preliminary results are promising but should be examined in a larger population with long-term follow-up.

Risk factors for postoperative intracranial infections in patients with pituitary adenoma after endoscopic endonasal transsphenoidal surgery: pneumocephalus deserves further study

OBJECTIVE

The authors sought to identify the relevance between pneumocephalus and postoperative intracranial infections, as well as bacteriological characteristics and risk factors for intracranial infections, in patients with pituitary adenomas after endoscopic endonasal transsphenoidal surgery.

METHODS

In total, data from 251 consecutive patients with pituitary adenomas who underwent pure endoscopic endonasal transsphenoidal surgeries from 2014 to 2018 were reviewed for preoperative comorbidities, intraoperative techniques, and postoperative care.

RESULTS

This retrospective study found 18 cases of postoperative pneumocephalus (7.17%), 9 CNS infections (3.59%), and 12 CSF leaks (4.78%). Of the patients with pneumocephalus, 5 (27.8%) had CNS infections. In patients with CNS infections, the culture results were positive in 7 cases and negative in 2 cases. The statistical analysis suggested that pneumocephalus (maximum bubble diameter of ≥ 1 cm), diaphragmatic defects (intraoperative CSF leak, Kelly grade ≥ 1), and a postoperative CSF leak are risk factors for postoperative CNS infections.

CONCLUSIONS

In pituitary adenoma patients who underwent pure endoscopic endonasal transsphenoidal surgeries, intraoperative saddle reconstruction has a crucial role for patients with postoperative intracranial infections. Additionally, postoperative pneumocephalus plays an important role in predicting intracranial infections that must not be neglected. Therefore, neurosurgeons should pay close attention to the discovery of postoperative intracranial pneumocephalus because this factor is as important as a postoperative CSF leak. Pneumocephalus (maximum bubble diameter of ≥ 1 cm), diaphragmatic defects (an intraoperative CSF leak, Kelly grade ≥ 1), and a postoperative CSF leak were risk factors predictive of postoperative intracranial infections. In addition, it is essential that operative procedures be carefully performed to avoid diaphragmatic defects, to reduce exposure to the external environment, and to decrease patients’ suffering.

Long-term sinonasal outcomes after endoscopic skull base surgery with nasoseptal flap reconstruction

OBJECTIVES

The utilization of the nasoseptal flap (NSF) in endoscopic anterior skull base surgery (EASB) has resulted in reduced rates of postoperative cerebrospinal fluid leak (CSF). The long-term impact on sinonasal function after surgery remains incompletely defined.

METHODS

A consecutive series of patients undergoing EASB with NSF and with at least 3 years follow-up was prospectively evaluated. Patient demographics, pre- and postoperative Sino-nasal Outcome Test-22 (SNOT-22) scores, Lund-Mackay scores (LMS), CSF leak, and sinonasal complications were analyzed.

RESULTS

A total of 46 patients undergoing EASB with NSF met inclusion criteria. The mean follow-up was 67.4 months (range 39-90, standard deviation [SD] 14.2 months). No statistically significant differences were noted between the mean overall pre- (16) and postoperative SNOT-22 scores (18). SNOT-22 scores improved in 27 patients (58.7%), deteriorated in 17 patients (37.0%) and stayed the same in two patients (4.3%). Deterioration in SNOT-22 scores was greater in younger (mean change + 7.2 [SD17.4] vs. older patients -3.4 [SD 7.5], P = 0.010). A statistically significant increase in LMS was noted (mean preoperative LMS0.9 vs. mean postoperative LMS 2.2, P = 0.001). The LMS decreased in nine patients (19.6%), increased in 22 patients (47.8%), and remained the same in 15 patients (32.6%). One patient (2.2%) developed a postoperative CSF leak following resection of metastatic skull base lesion and was successfully treated with placement of a lumbar drain, Foley catheter balloon, and strict bed rest. One patient (2.2%) developed a postoperative mucocele requiring decompression 3 years after initial surgery.

CONCLUSION

Whereas long-term sinonasal quality of life is overall improved in the majority of patients following NSF use for EASB, younger patients show higher incidence of deterioration. Increased sinus opacification on imaging is generally noted and may require continued follow-up and management. The incidence of reoperation for symptomatic mucocele formation is low.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:1035-1040, 2019.

Reconstruction of Dural Defects in Endoscopic Transnasal Approaches for Intradural Lesions Using Multilayered Fascia with a Pressure-Control Spinal Drainage System

OBJECTIVE

Nasoseptal flap reconstruction is a widely accepted method for reducing cerebrospinal fluid (CSF) leakage after endoscopic transnasal surgeries (ETSs). However, this method is associated with nasal complications and is difficult to apply repeatedly in recurrent cases. Therefore, alternative methods are needed.

METHODS

Layers of autologous fascia lata were placed on the inside and outside of the dural defect to sufficiently cover it, and the grafts were compressed with an inflated balloon. A lumbar drainage system with a pressure-control valve was used for 72 hours postoperatively. We retrospectively analyzed data on patients with skull base lesions showing intracranial extensions that required wide opening of the ventral dura in ETS. Fifty cases (47 skull base tumors and 3 others) were included, 28 of which were recurrent cases.

RESULTS

In 21 cases (42%), the nasal septum was not intact because of the previous ETS. Seventeen patients (34%) had a history of radiotherapy and 9 (18%) had undergone multisession radiotherapies. None of the 50 patients required additional surgery for postoperative CSF rhinorrhea, and 2 had intermittent CSF leakage that resolved with prolonged lumbar drainage placement for a week. Previous multisession radiotherapy was the only significant risk factor for the need of prolonged drainage (P = 0.029).

CONCLUSIONS

The multilayer closure method with a pressure-control spinal drainage system is a simple, safe, and effective method for preventing postoperative CSF leakage, which can be readily applied to dural defects in any parts of the skull base regions and in patients with various conditions.

The Impact of Age on Long-Term Quality of Life After Endonasal Endoscopic Resection of Skull Base Meningiomas

BACKGROUND

Midline ventral skull base meningiomas may be amenable to an endonasal endoscopic approach, which has theoretical advantages and may help preserve quality of life (QOL) when compared with transcranial approaches.

OBJECTIVE

To investigate the effect of age on QOL following endonasal endoscopic surgery, given the documented impact of age on QOL outcomes following transcranial resection of midline ventral skull base meningiomas.

METHODS

We reviewed a prospectively acquired database of endonasal endoscopic surgery for meningiomas. Inclusion criteria included patients who had completed long-term postoperative (≥6 months follow-up) QOL questionnaires (Anterior Skull Base Questionnaire [ASBQ] and Sino-Nasal Outcome Test [SNOT-22]). Postoperative QOL scores were also compared with preoperative QOL in a patient subset.

RESULTS

Long-term QOL data were available in 34 patients. Average postoperative ASBQ and SNOT-22 scores were 3.39 and 23.0, respectively. Better QOL was statistically associated with age <55 (P = .02). In a subset of patients, preoperative and postoperative ASBQ and SNOT-22 scores were compared. Only SNOT-22 scores significantly increased from 15.9 + 20.8 to 25.9 + 19.5 (P = .04).

CONCLUSION

We report the first study specifically evaluating long-term QOL after endonasal endoscopic resection of skull base meningiomas. QOL was decreased postoperatively in patients aged ≥55.

ABBREVIATIONS

ASBQ, Anterior Skull Base QuestionnaireGTR, gross total resectionQOL, quality of lifeSNOT-22, 22-item Sino-Nasal Outcome Test.

Transorbital endoscopic approach for exposure of the sylvian fissure, middle cerebral artery and crural cistern: an anatomical study

BACKGROUND

The availability of minimal access instrumentation and endoscopic visualization has revolutionized the field of minimally invasive skull base surgery. The transorbital endoscopic approach using an eyelid incision has been proposed as a new minimally invasive technique for the treatment of skull base pathology, mostly extradural tumors. Our study aims to evaluate the anatomical aspects and potential role of the transorbital endoscopic approach for exposure of the sylvian fissure, middle cerebral artery and crural cistern.

METHODS

An anatomical dissection was performed in four freshly injected cadaver heads (8 orbits) using 0- and 30-degree endoscopes. First, an endoscopic endonasal medial orbital decompression was done to facilitate medial retraction of the orbit. An endoscopic transorbital approach through an eyelid incision, with drilling of the posterior wall of the orbit and lesser sphenoidal wing, was then performed to expose the sylvian fissure and crural cisterns. A stepwise anatomical description of the approach and visualized anatomy is detailed.

RESULTS

A superior eyelid incision followed by orbital retraction provided a surgical window of approximately 1.2 cm (range 1.0-1.5 cm) for endoscopic transorbital dissection. The superior (SOF) and inferior (IOF) orbital fissures represent the medial limits of the approach and are identified in the initial part of the procedure. Drilling of the orbital roof (lateral and superior to the SOF), greater sphenoidal wing (lateral to the SOF and IOF) and lesser sphenoidal wing exposed the anterior and middle fossa dura. A square-shaped dural opening provided visualization of the posterior orbital gyri, sylvian fissure and temporal pole. Intradural dissection allowed exposure of the sphenoidal portion of the sylvian fissure, M1, MCA bifurcation and M2 branches and lenticulostriate perforators. Dissection of the medial aspect of the sylvian and carotid cisterns with a 30-degree endoscope allowed exposure of the mesial temporal lobe and crural cistern.

CONCLUSIONS

The transorbital endoscopic approach allows successful exposure of the sphenoidal portion of the sylvian fissure and M1 and M2 segments of the middle cerebral artery. Angled endoscopes may provide visualization of the mesial temporal lobe and crural cistern. Although our anatomical study demonstrates the feasibility of intradural dissection and closure via an endoscopic transorbital approach, further studies are necessary to evaluate its role in the clinical scenario.

Reoperation for growth hormone-secreting pituitary adenomas: report on an endonasal endoscopic series with a systematic review and meta-analysis of the literature

OBJECTIVE Surgery is generally the first-line therapy for acromegaly. For patients with residual or recurrent tumors, several treatment options exist, including repeat surgery, medical therapy, and radiation. Reoperation for recurrent acromegaly has been associated with poor results, with hormonal control usually achieved in fewer than 50% of cases. Extended endonasal endoscopic approaches (EEAs) may potentially improve the results of reoperation for acromegaly by providing increased visibility and maneuverability in parasellar areas. METHODS A database of all patients treated in the authors' center between July 2004 and February 2016 was reviewed. Cases involving patients with acromegaly secondary to growth hormone (GH)-secreting adenomas who underwent EEA were selected for chart review and divided into 2 groups: first-time surgery and reoperation. Disease control was defined by 2010 guidelines. Clinical and radiological characteristics and outcome data were extracted. A systematic review was done through a MEDLINE database search (2000-2016) to identify studies on the surgical treatment of acromegaly. Using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, the included studies were reviewed for surgical approach, tumor size, cavernous sinus invasion, disease control, and complications. Cases were divided into reoperation or first-time surgery for comparative analysis. RESULTS A total of 44 patients from the authors' institution were included in this study. Of these patients, 2 underwent both first-time surgery and reoperation during the study period and were therefore included in both groups. Thus data from 46 surgical cases were analyzed (35 first-time operations and 11 reoperations). The mean length of follow-up was 70 months (range 6-150 months). The mean size of the reoperated tumors was 14.8 ± 10.0 mm (5 micro- and 6 macroadenomas). The patients' mean age at the time of surgery was younger in the reoperation group than in the first-time surgery group (34.3 ± 12.8 years vs 49.1 ± 15.7 years, p = 0.007) and the mean preoperative GH level was also lower (7.7 ± 13.1 μg/L vs 25.6 ± 36.8 μg/L, p = 0.04). There was no statistically significant difference in disease control rates between the reoperation (7 [63.6%] of 11) and first-time surgery (25 [71.4%] of 33) groups (p = 0.71). Univariate analysis showed that older age, smaller tumor size, lower preoperative GH level, lower preoperative IGF-I level, and absence of cavernous sinus invasion were associated with higher chances of disease control in the first-time surgery group, whereas only absence of cavernous sinus invasion was associated with disease control in the reoperation group (p = 0.01). There was 1 case (9%) of transient diabetes insipidus and hypogonadism and 1 (9%) postoperative nasal infection after reoperation. The systematic review retrieved 29 papers with 161 reoperation and 2189 first-time surgery cases. Overall disease control for reoperation was 46.8% (95% CI 20%-74%) versus 56.4% (95% CI 49%-63%) for first-time operation. Reoperation and first-time surgery had similar control rates for microadenomas (73.6% [95% CI 32%-98%] vs 77.6% [95% CI 68%-85%]); however, reoperation was associated with substantially lower control rates for macroadenomas (27.5% [95% CI 5%-57%] vs 54.3% [95% CI 45%-62%]) and tumors invading the cavernous sinus (14.7% [95% CI 4%-29%] vs 38.5% [95% CI 27%-50%]). CONCLUSIONS Reoperative EEA for acromegaly had results similar to those for first-time surgery and rates of control for macroadenomas that were better than historical rates. Cavernous sinus invasion continues to be a negative prognostic indicator for disease control; however, results with EEA show improvement compared with results reported in the prior literature.

Outcomes After Endoscopic Endonasal Resection of Craniopharyngiomas in the Pediatric Population

BACKGROUND

Craniopharyngiomas have traditionally been treated via open transcranial approaches. More recently, endoscopic transsphenoidal approaches have been increasingly used; however, few case series exist in the pediatric population.

METHODS

A retrospective review of patients (aged <18 years) undergoing endoscopic transsphenoidal resection of craniopharyngiomas between 1995 and 2016 was performed. Preoperative data included presenting symptoms, tumor size, location, and components. Postoperative outcomes included symptom resolution, visual outcomes, endocrine outcomes, disease recurrence, and major complications.

RESULTS

Sixteen pediatric patients with mean age of 11.0 years (range, 5-15 years) were included. The median follow-up time was 56.2 months. Mean maximal tumor diameter was 3.98 cm. Most of the tumors had suprasellar (93.8%) and intrasellar (68.8%) components. The gross total resection rate was 93.8%. The most common presenting symptoms were vision changes (81.3%) and increased intracranial pressure (56.3%). Most patients (66.7%) had their presenting symptoms resolved by their first postoperative visit. Vision improved or remained normal in 69.2% of patients. Postoperatively, new incidence of panhypopituitarism or diabetes insipidus developed in 63.6% and 46.7% of patients, respectively. New hypothalamic obesity developed in 28.6% of patients. The postoperative cerebrospinal fluid leak rate was 18.8%. One patient died of intraventricular hemorrhage postoperatively. The major complication rate was 12.5%. Disease recurrence occurred in 1 patient with gross total resection (6.3%).

CONCLUSIONS

Endoscopic transsphenoidal resection for craniopharyngiomas can achieve high rates of total resection with low rates of disease recurrence in larger tumors than previously described. However, hypothalamic-pituitary dysfunction and cerebrospinal fluid leak remain significant postoperative morbidities.

Reoperative endoscopic endonasal surgery for residual or recurrent pituitary adenomas

OBJECTIVE

Regrowth of the lesion after surgical removal of pituitary adenomas is uncommon unless subtotal resection was originally achieved in the first surgery. Treatment for recurrent tumor can involve surgery or radiotherapy. Locations of residual tumor may vary based on the original approach. The authors evaluated the specific sites of residual or recurrent tumor after different transsphenoidal approaches and describe the surgical outcome of endoscopic endonasal transsphenoidal reoperation.

METHODS

The authors analyzed a prospectively collected database of a consecutive series of patients who had undergone endoscopic endonasal surgeries for residual or recurrent pituitary adenomas after an original transsphenoidal microscopic or endoscopic surgery. The site of the recurrent tumor and outcome after reoperation were noted and correlated with the primary surgical approach. The chi-square or Fisher exact test was used to compare categorical variables, and the Mann-Whitney U-test was used to compare continuous variables between surgical groups.

RESULTS

Forty-one patients underwent surgery for residual/recurrent pituitary adenoma from 2004 to 2015 at Weill Cornell Medical College. The previous treatment was a transsphenoidal microscopic (n = 22) and endoscopic endonasal (n = 19) surgery. In 83.3% patients (n = 30/36) there was postoperative residual tumor after the initial surgery. A residual tumor following endonasal endoscopic surgery was less common in the sphenoid sinus (10.5%; 2/19) than it was after microscopic transsphenoidal surgery (72.7%; n =16/22; p = 0.004). Gross-total resection (GTR) was achieved in 58.5%, and either GTR or near-total resection was achieved in 92.7%. Across all cases, the average extent of resection was 93.7%. The rate of GTR was lower in patients with Knosp-Steiner Grade 3–4 invasion (p < 0.0005). Postoperative CSF leak was seen in only one case (2.4%), which stopped with lumbar drainage. Visual fields improved in 52.9% (n = 9/17) of patients and were stable in 47% (n = 8/17). Endocrine remission was achieved in 77.8% (n = 14/18) of cases, 12 by surgery alone and 2 by adjuvant medical (n = 1) and radiation (n = 1) therapy. New diabetes insipidus occurred in 4.9% (n = 2/41) of patients—in one of whom an additional single anterior hormonal axis was compromised—and 9.7% (n = 4/41) of patients had a new anterior pituitary hormonal insufficiency.

CONCLUSIONS

Endonasal endoscopic reoperation is extremely effective at removing recurrent or residual pituitary adenomas that remain after a prior surgery, and it may be preferable to radiation therapy particularly in symptomatic patients. Achievement of GTR is less common when lateral cavernous sinus invasion is present. The locations of residual/recurrent tumor were more likely sphenoidal and parasellar following a prior microscopic transsphenoidal surgery and sellar following a prior endonasal endoscopic surgery.

Layered sellar reconstruction with avascular free grafts: Acceptable alternative to the nasoseptal flap for repair of low-volume intraoperative cerebrospinal fluid leak

BACKGROUND

Although the nasoseptal flap has become the method of choice for reconstruction of intraoperative cerebrospinal fluid (CSF) leak in endoscopic minimally invasive surgery of the skull base, layered avascular graft techniques, including allografts and middle turbinate mucosal autografts, may provide comparable reconstructive success with decreased nasal morbidity.

OBJECTIVE

To describe a method of reconstruction of intraoperative CSF leak in endoscopic surgery of the sella turcica and analyze its postoperative success rate and associated comorbidities.

METHODS

A retrospective review of expanded endonasal sellar tumor resections from 2008-2014 was performed, and cases of layered intraoperative skull base reconstruction with avascular free grafts were identified. Demographic factors and comorbidities that predisposed to reconstruction failure (obstructive sleep apnea, obesity) were determined. Reconstruction-related nasal complications were also identified. Postoperative CSF leak rate was determined, and statistical analysis was performed to identify predictive factors for reconstructive failure.

RESULTS

Seventy-three cases were identified. Layered closure with avascular free grafts was performed. There were five cases of postoperative CSF leak (6.85%). The mean follow-up was 19 months (range, 1-76 months). Intraoperative high-flow CSF leak was a significant predictor of reconstruction failure on univariate (odds ratio 22 [95% confidence interval, 2.26-214]; p = 0.008) and multivariate analysis (odds ratio 33.6 [95% confidence interval, 2.30-492]; p = 0.010). There were no significant differences in postoperative leak rates among bony overlay graft types. There were five patients (7.9%) who experienced persistent crusting after surgery. There were no significant differences in crusting rates between allografts and mucosal grafts. There were no postoperative mucoceles.

CONCLUSION

In cases of low-volume intraoperative CSF leak, layered skull base repair with avascular free grafts was an acceptable alternative to the nasoseptal flap, which may reduce prolonged sinonasal healing and donor-site morbidities.

Sandwich technique using fibrin-coated collagen fleece for sellar reconstruction in large dural defects during transsphenoidal surgery

PURPOSE

Various surgical methods to prevent intraoperative and postoperative cerebrospinal fluid (CSF) leaks during transsphenoidal approach (TSA) surgeries have been reported, but surgical techniques to address large dural defects have been less thoroughly investigated in the literature. The authors retrospectively evaluated the usefulness of the sandwich technique using fibrin-coated collagen fleece (TachoSil) to prevent intraoperative CSF leakage from large dural defects in TSA surgery.

METHODS

In total, 101 cases of intraoperative CSF leaks were observed among 465 patients who underwent TSA surgery at a single university hospital between 2002 and 2014. Among them, cases with Grade 3 intraoperative CSF leakages and large diaphragmatic/dural defects were reconstructed via the sandwich technique using TachoSil or via the conventional technique using simple intrasellar packing with fat or synthetic materials, and these cases were enrolled in this study.

RESULTS

A total of 28 cases with Grade 3 intraoperative CSF leakages were identified and analyzed. The sandwich technique using TachoSil was applied in 13 cases, and the conventional technique was applied in 15 cases. The postoperative CSF leakage was significantly decreased by the sandwich technique as compared to the conventional technique (retrospectively, 0 cases vs. 4 cases (30.8%); P=0.044).

CONCLUSION

The sandwich technique using TachoSil can effectively prevent CSF leakage in cases with large dural defects during TSA surgery.

Endonasal endoscopic pituitary surgery in the elderly

OBJECTIVE Pituitary adenomas are benign, slow-growing tumors that cause symptoms either through mass effect or hormone overproduction. The decision to operate on a healthy young person is relatively straightforward. In the elderly population, however, the risks of complications may increase, rendering the decision more complex. Few studies have documented the risks of surgery using the endonasal endoscopic approach in a large number of elderly patients. The purpose of this study was to audit a single center's data regarding outcomes of purely endoscopic endonasal transsphenoidal resection of pituitary adenomas in elderly patients and to compare them to the current literature. METHODS A retrospective review of a prospectively acquired database of all endonasal endoscopic surgeries done by the senior authors was queried for patients aged 60-69 years and for those aged 70 years or older. Demographic and radiographic preoperative data were reviewed. Outcomes with respect to extent of resection and complications were examined and compared with appropriate statistical tests. RESULTS A total of 135 patents were identified (81 aged 60-69 years and 54 aged 70 years or older [70+]). The average tumor diameter was slightly larger for the patients in the 70+ age group (mean [SD] 25.7 ± 9.2 mm) than for patients aged 60-69 years (23.1 ± 9.8 mm, p = 0.056). There was no significant difference in intraoperative blood loss (p > 0.99), length of stay (p = 0.22), or duration of follow-up (p = 0.21) between the 2 groups. There was a 7.4% complication rate in patients aged 60-69 years (3 nasal and 3 medical complications) and an 18.5% complication rate in patients older than 70 years (4 cranial, 3 nasal, 1 visual, and 2 medical complications; p = 0.05 overall and 0.013 for cranial complications). Cranial complications in the 70+ age category included 2 postoperative hematomas, 1 pseudoaneurysm formation, and 1 case of symptomatic subdural hygromas. CONCLUSIONS Endonasal endoscopic surgery in elderly patients is safe, but there is a graded increase in complication rates with increasing age. The decision to operate on an asymptomatic or mildly symptomatic patient in these age groups should take this increasing complication rate into account. The use of a lumbar drain or lumbar punctures should be weighed against the risk of subdural hematoma in patients with preexisting atrophy.

Endoscopic endonasal versus open transcranial resection of craniopharyngiomas: a case-matched single-institution analysis

OBJECTIVE The authors compared clinical and radiological outcomes after resection of midline craniopharyngiomas via an endoscopic endonasal approach (EEA) versus an open transcranial approach (TCA) at a single institution in a series in which the tumors were selected to be equally amenable to gross-total resection (GTR) with either approach. METHODS A single-institution retrospective review of previously untreated adult midline craniopharyngiomas was performed. Lesions were evaluated by 4 neurosurgeons blinded to the actual approach used to identify cases that were equally amenable to GTR using either an EEA or TCA. Radiological and clinical outcome data were assessed. RESULTS Twenty-six cases amenable to either approach were identified, 21 EEA and 5 TCA. Cases involving tumors that were resected via a TCA had a trend toward larger diameter (p = 0.10) but were otherwise equivalent in preoperative clinical and radiological characteristics. GTR was achieved in a greater proportion of cases removed with an EEA than a TCA (90% vs 40%, respectively; p = 0.009). Endoscopic resection was associated with superior visual restoration (63% vs 0%; p < 0.05), a decreased incidence of recurrence (p < 0.001), lower increase in FLAIR signal postoperatively (-0.16 ± 4.6 cm³ vs 14.4 ± 14.0 cm³; p < 0.001), and fewer complications (20% vs 80% of patients; p < 0.001). Significantly more TCA patients suffered postoperative cognitive loss (80% vs 0; p < 0.0001). CONCLUSIONS An EEA is a safe and effective approach to suprasellar craniopharyngiomas amenable to GTR. For this select group of cases, the EEA may provide higher rates of GTR and visual improvement with fewer complications compared with a TCA.

Is the Keros classification alone enough to identify patients with the 'dangerous ethmoid'? An anatomical study

CONCLUSION

By means of three-dimensional display of the critical measurements, the authors suggest a novel definition of 'dangerous ethmoid'. Parallel to Keros type III, the proposed determining factors include: olfactory fossa width >6 mm, its distance to the medial nasal concha (turbinate) <20 mm and to the orbit interval of <10 mm. Clinical evaluation of these preliminary criteria based only on radiological data is required and underway.

OBJECTIVES

Detailed pre-operative assessment of sinus computer tomography (CT) scans reduces the frequency of severe complications in patients undergoing endoscopic sinus surgery (ESS). The authors aimed to identify a sub-set of anatomical features pre-disposing to major post-operative complications.

METHOD

Sinus computer tomography (CT) scans of patients of a single institution qualified for ESS were examined. Besides the Keros classification, authors focused on the anatomic measurements as follows: the olfactory fossa depth, width, and its distance from the medial nasal concha and the medial wall of the orbit (referred to as 'critical measurements'). The sample comprised 120 consecutive CT exams, without clinical validation.

RESULTS

Keros type I, II, and III was noted in 9.2%, 75.8%, and 15.0% of cases, respectively. Despite some statistically significant correlations, it was not possible to identify the patient age, sex, and side of body clearly correlating with the critical measurements.

Endoscopic endonasal versus transcranial approach to tuberculum sellae and planum sphenoidale meningiomas in a similar cohort of patients

OBJECTIVE Planum sphenoidale (PS) and tuberculum sellae (TS) meningiomas cause visual symptoms due to compression of the optic chiasm. The treatment of choice is surgical removal with the goal of improving vision and achieving complete tumor removal. Two options exist to remove these tumors: the transcranial approach (TCA) and the endonasal endoscopic approach (EEA). Significant controversy exists regarding which approach provides the best results and whether there is a subset of patients for whom an EEA may be more suitable. Comparisons using a similar cohort of patients, namely, those suitable for gross-total resection with EEA, are lacking from the literature. METHODS The authors reviewed all cases of PS and TS meningiomas that were surgically removed at Weill Cornell Medical College between 2000 and 2015 (TCA) and 2008 and 2015 (EEA). All cases were shown to a panel of 3 neurosurgeons to find only those tumors that could be removed equally well either through an EEA or TCA to standardize both groups. Volumetric measurements of preoperative and postoperative tumor size, FLAIR images, and apparent diffusion coefficient maps were assessed by 2 independent reviewers and compared to assess extent of resection and trauma to the surrounding brain. Visual outcome and complications were also compared. RESULTS Thirty-two patients were identified who underwent either EEA (n = 17) or TCA (n = 15). The preoperative tumor size was comparable (mean 5.58 ± 3.42 vs 5.04 ± 3.38 cm³ [± SD], p = 0.661). The average extent of resection achieved was not significantly different between the 2 groups (98.80% ± 3.32% vs 95.13% ± 11.69%, p = 0.206). Postoperatively, the TCA group demonstrated a significant increase in the FLAIR/edema signal compared with EEA patients (4.15 ± 7.10 vs -0.69 ± 2.73 cm³, p = 0.014). In addition, the postoperative diffusion-weighted imaging signal of cytotoxic ischemic damage was significantly higher in the TCA group than in the EEA group (1.88 ± 1.96 vs 0.40 ± 0.55 cm³, p =0.008). Overall, significantly more EEA patients experienced improved or stable visual outcomes compared with TCA patients (93% vs 56%, p = 0.049). Visual deterioration was greater after TCA than EEA (44% vs 0%, p = 0.012). While more patients experienced postoperative seizures after TCA than after EEA (27% vs 0%, p = 0.038), there was a trend toward more CSF leakage and anosmia after EEA than after TCA (11.8% vs 0%, p = 0.486 and 11.8% vs 0%, p = 0.118, respectively). CONCLUSIONS In this small single-institution study of similarly sized and located PS and TS meningiomas, EEA provided equivalent rates of resection with better visual results, less trauma to the brain, and fewer seizures. These preliminary results merit further investigation in a larger multiinstitutional study and may support EEA resection by experienced surgeons in a subset of carefully selected PS and TS meningiomas.

Endoscopic Endonasal Management of Craniopharyngioma

Craniopharyngioma is a rare clinical entity that poses a significant management challenge given their location and propensity to recur. As part of a minimally disruptive treatment paradigm, the expanded endonasal approach has the potential to improve rates of resection, improve postoperative visual recovery, and minimize surgical morbidity. This article updates the otolaryngologic community on the basic principles and techniques regarding the incorporation of the endoscopic, endonasal approach in the management paradigm of craniopharyngioma.

Cerebrospinal fluid leaks in extended endoscopic transsphenoidal surgery: covering all the angles

Following extended endoscopic transsphenoidal approach (EETSA), cerebrospinal fluid (CSF) leak rate has been reported in the range of 5-50 %. Novel closure techniques, such as the nasoseptal flap and other multilayered repairs improved the outcomes significantly but took most of our focus. Little attention, however, was given to other aspects of the equation such as nasal support-to support the heavy weight of such repairs-and lumbar drains. These are important because they diminish the forces acting on both sides of the repair, hence covering all the angles. We reviewed data of 98 consecutive patients who underwent an EETSA between 1999 and 2014. We analyzed the rates of CSF leak throughout the years and with every modification added to our closure technique. Common pathologies encountered were invasive adenomas, meningiomas, chordomas, and craniopharyngiomas. CSF leak occurred overall in five patients (5.1 %). The nasoseptal flap decreased the rate of CSF leak but not significantly (P = 0.112), while placing a nasal trumpet to support our repair resulted in significant decrease in CSF leak rate (P = 0.0013). In the last 2 years of our series, when all modifications took place and all angles were covered, there was one leak in 35 cases (2.8 %). A protocol that covers all the angles by a good multilayered repair (regardless of its type and materials) while diminishing the forces acting on both sides of the repair leads to a minimal rate of CSF leak. No principle alone is effective individually.