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

Endoscopic Transpterygoid Corridor for Petroclival Tumors: Case Series and Technical Nuances

Background

The petroclival area is a technically challenging region to operate owing to the proximity of the internal carotid artery (ICA) and the need to obtain gross total excision of tumors in this area as they are often resistant to radiotherapy.

Objective

We present our experience with the endonasal endoscopic transpterygoid approach in managing tumors of the petroclival region and discuss various operative nuances for safer resection.

Materials and Methods

A retrospective study of all consecutive cases of lesions occupying the petroclival region that were operated via endonasal endoscopic transpterygoid approach at our center between January 2016 and December 2021 was performed.

Results

The study included 14 cases of lesions occupying the petroclival region. Gross total resection by intraoperative observation was achieved in 10 patients, near total decompression was performed in two patients, and the remaining two patients underwent marsupialization of lesion. Postoperatively, one patient had right Lower motor neuron (LMN) facial nerve palsy and one patient required surgery for Cerebrospinal fluid (CSF) rhinorrhea on postoperative day 8. The mean duration of follow-up was 13.8 ± 16.6 months (range: 2-59 months). Four of six patients with visual symptoms on presentation reported improvement in vision, and the other two patients had a stable vision on follow-up. Two patients received radiotherapy postsurgery. No mortality was noted.

Conclusion

The extended endonasal endoscopic transpterygoid approach can be safely and efficiently used for petroclival lesions. Very sound knowledge of anatomical relationship, use of intraoperative image guidance to avoid injury to ICA, and multilayer reconstruction with a vascularized nasoseptal flap are required to optimize the clinical outcome.

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.

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.

Sinonasal outcomes associated with the use of BioGlue® in endoscopic transsphenoidal pituitary surgery

Concerns have been raised in the neurosurgical literature regarding the use of BioGlue®, a tissue sealant initially developed for cardiothoracic surgery, due to reports of an increased incidence of infection, wound breakdown, and CSF fistulae. The aim of this study was to determine if the use of BioGlue® in skull base repair impacts on the sinonasal outcomes and the incidence of post-operative infection following endoscopic pituitary surgery. SNOT-22 questionnaires were completed pre-operatively, and at 6, 12, and 24 weeks post-operatively by 50 patients. Pre- and post-operative MRI scans were reviewed and assessed for evidence of post-operative sinusitis. Patient records were consulted to ascertain the incidence of post-operative infection. Repeated measures ANOVA and Wilcoxon signed rank test were used for data analysis. Statistical analysis revealed a significant difference in the mean SNOT-22 scores across the four time intervals (F(1.605, 78.642) = 9.180, p = 0.001). This difference was powered by a deterioration at 6 weeks that recovered completely by 12 weeks. The mean SNOT-22 score in the study cohort at 24 weeks was 16.84/110 (range 0-57, ± 2.04) which was lower than the mean pre-operative score and is consistent with mild rhinosinusitis. There were no cases of post-operative meningitis and 1/50 (2%) case of post-operative sinusitis in this cohort. The use of BioGlue® in endoscopic endonasal pituitary surgery does not appear to lead to significant sinonasal morbidity. Previous concerns about the use of BioGlue® in transcranial procedures may not apply to extradural application of this tissue sealant in endoscopic transnasal surgery.

New Approach for Endoscopic Endonasal Transsphenoidal Pituitary Surgery: Modified Nasoseptal Rescue Flap

INTRODUCTION

Endoscopic endonasal approach has become popularly preferred for pituitary surgery in recent years. In this study we described a new technique which is developed by the first author and which is modified from The Rivera-Serrano "salvage" flap approach. With this new technique the septum morbidity was completely prevented and a wider and more comfortable vision was provided for the operation.

MATERIALMETHOD

This study consists 7 patients who underwent endoscopic endonasal transsphenoidal pituitary surgery (EETPS) with the described technique (modified salvage flap technique) between 2017 and 2019 and 13 patients underwent EETPS using salvage flap technique. The follow-up period was at least 6 months (24-6 months) for septal integrity.

RESULTS

Intraoperative septum integrity was observed in all 7 patients who were treated with modified rescue flap technique. In 9 of 13 patients who had salvage flap technique, intraoperative septum posterior defects were observed. In postoperative follow-up (min postop 3 months), endoscopic examination showed no septal perforation in 6 patients who were treated with modified rescue flap technique, and 1 patient had 2 × 2 mm perforation posteriorly. In postoperative endoscopic follow-up of 13 patients who underwent salvage flap technique (min postop 3 months), 4 patients had complete septal integrity, while 9 patients had different sizes of posterior septal perforation.

CONCLUSION

According to other described approach techniques, our modification using a pedicle and septum protective-transposition technique provides improved access to the downstream side of the sphenoid sinus and clivus, allowing the pedicle to slide down and take a more horizontal position. The improved maneuverability of the pedicle created in the case of cerebrospinal fluid leakage as a complication also allows it to be used as a bilateral wing to cover the exposed bone. We think that this technique is the best method to be used for EETPS with modified saline flap technique.

The Effects of Using Bioglue in Nasal Septal Surgery

OBJECTIVES

Nasal septal surgery is one of the most common surgical procedure performed by otolaryngologists. Nasal packs are used for bleeding control, prevention of septal hematoma, replacement of mucoperichondrial flaps, and stabilization of the septum after nasal septal surgery. The aim of this study was to investigate the effects of albumin-glutaraldehyde-based tissue adhesive (Bioglue), which can be used as an alternative to nasal pack on the nasal septum after experimental nasal septum surgery.

METHODS

A total of 16 female Wistar albino rats were randomly separated into the study group (n = 10) and the control group (n = 6). After raising the mucoperichondrial flap on one side of the septum, Bioglue was used to fix the mucoperichondrial flap over the septal cartilage ın the study group and nasal packs (Merocel) were used for fixation in the control group. The rats were sacrificed at 2 and 4 weeks after septoplasty. All the tissue samples were evaluated under light microscope by the same pathologist in respect of foreign-body reaction, degree of inflammation, granulation tissue, fibrosis, cartilage damage, and cilia and goblet cell damage. In the control group, the Merocel packs were removed after 2 days and the groups were compared in terms of hematoma.

RESULTS

No hematoma was observed in any group. Septal perforation was determined in all the study group participants and loss of cilia and goblet cells and foreign-body reaction were found in 8 samples of the study group participants and in none of the control group.

CONCLUSIONS

The results of this study show that Bioglue caused segmental cartilage injury; therefore, it may not suitable for use following septal surgery.

Various Strategies of Transsphenoidal Pseudocapsule-Based Extracapsular Resection in Noninvasive Functional Pituitary Adenomas and their Effectiveness and Safety

Introduction

Increasing attention has been paid to the pseudocapsule-based extracapsular resection in transsphenoidal surgery for pituitary adenomas. Prior reports focused more on Cushing disease or nonfunctional pituitary adenomas. In this study we present systematic research, especially concerning all kinds of noninvasive functional pituitary adenomas (NIFPAs) adopting various strategies of extracapsular resection, in order to evaluate the effectiveness and safety of these surgical methods for NIFPAs.

Materials and Methods

From October 2008 to November 2014, 116 patients suffering from NIFPAs underwent pseudocapsule-based extracapsular resection (ER) with different surgical strategies; that is, by a microscope or endoscope via the endonasal transsphenoidal approach. During the same period, 90 patients suffering NIFPAs also underwent traditional transsphenoidal intracapsular resection (IR). In different postoperative periods, we re-examined the endocrine series and recorded the complications. Enhanced magnetic resonance imaging examination was also performed three months later.

Results

In the ER and IR group, the tumors were completely removed in 97 (83.7%) and 62 (68.9%) cases, whereas the endocrine disorders were remitted in 89 (76.7%) and 53 (58.9%) cases, respectively. Statistical analyses to compare the overall complete resection rates and the overall endocrine remission rates in both groups showed significant differences (P = 0.028 and 0.006, respectively). Intraoperative rhinorrhea occurred in 26.7% patients of the ER group and 13.3% of the IR group, showing a significant difference (P = 0.019). Transient diabetes insipidus occurred in 73.3% patients of the ER group and 63.3% of the IR group, with no difference between groups (P = 0.126). There was no case with intracranial hematoma or pituitary crisis in both the groups.

Conclusion

With our various surgical strategies of ER, the patients can achieve content imaging resection, high and sustained endocrine remission, which are effective and safe for NIFPAs.

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.

Soft tissue grafts for dural reconstruction after meningioma surgery

The meninges are involved in various pathologies and are often directly or indirectly severed during surgical procedures, especially the dura mater. This can pose a real challenge for the surgeon, as a proper reconstruction of the meninges is important to prevent complications such as cerebrospinal fluid leak (CSF). A variety of techniques for dural reconstruction have been described, employing natural and artificial materials. A novel technique for dural reconstruction involves soft tissue grafts in the form of fibrous or fibromuscular flaps, which are placed on the dural defects to seal the gaps. These soft tissue grafts represent an appropriate scaffold for cell ingrowth and fibrosis, thus preventing CSF. In this pilot study, we described the application of soft tissue grafts for dural reconstruction in 10 patients who underwent convexity meningioma surgery.

Anterior Skull Base Reconstruction: Does Fat Preparation Matter?

Objectives  This article aims (1) to determine whether there is any difference in cerebrospinal fluid (CSF) leak rate after anterior skull base autologous fat reconstruction based on how the fat is prepared, and (2) to measure impact on surgical times by reconstruction type.

Design  Translational animal model surgical technique 3-arm trial, comparing two different methods of autologous fat skull base reconstruction versus a nonreconstructed control group.

Setting  Animal study.

Subjects  Adult Sprague-Dawley rats.

Main Outcome Measures  Resolution of CSF rhinorrhea after repair of a surgically created anterior skull base defect.

Results  Both wet (uncompressed) and dry (compressed) fat reconstruction of an anterior skull base defect demonstrated lower CSF leak rates than nonreconstructed defects. Dry fat reconstruction achieved significance in superiority of controlling CSF leak over no reconstruction (64% success vs. 31%); while wet fat reconstruction trended toward significance (50% vs. 31%). Reconstruction procedure time was longer than nonreconstructed controls, but there was no significant difference between type of fat preparation in surgical time.

Conclusions  This study demonstrates that drying and compressing the fat graft improves autologous fat reconstruction success for anterior skull base defects, and does not add significantly to surgical time over nonprepared fat.

Evolution of the graded repair of CSF leaks and skull base defects in endonasal endoscopic tumor surgery: trends in repair failure and meningitis rates in 509 patients

Objective

The authors previously described a graded approach to skull base repair following endonasal microscopic or endoscope-assisted tumor surgery. In this paper they review their experience with skull base reconstruction in the endoscopic era.

Methods

A retrospective review of a single-institution endonasal endoscopic patient database (April 2010–April 2017) was undertaken. Intraoperative CSF leaks were graded based on size (grade 0 [no leak], 1, 2, or 3), and repair technique was documented across grades. The series was divided into 2 epochs based on implementation of a strict perioperative antibiotic protocol and more liberal use of permanent and/or temporary buttresses; repair failure rates and postoperative meningitis rates were assessed for the 2 epochs and compared.

Results

In total, 551 operations were performed in 509 patients for parasellar pathology, including pituitary adenoma (66%), Rathke’s cleft cyst (7%), meningioma (6%), craniopharyngioma (4%), and other (17%). Extended approaches were used in 41% of cases. There were 9 postoperative CSF leaks (1.6%) and 6 cases of meningitis (1.1%). Postoperative leak rates for all 551 operations by grade 0, 1, 2, and 3 were 0%, 1.9%, 3.1%, and 4.8%, respectively. Fat grafts were used in 33%, 84%, 97%, and 100% of grade 0, 1, 2, and 3 leaks, respectively. Pedicled mucosal flaps (78 total) were used in 2.6% of grade 0–2 leaks (combined) and 79.5% of grade 3 leaks (60 nasoseptal and 6 middle turbinate flaps). Nasoseptal flap usage was highest for craniopharyngioma operations (80%) and lowest for pituitary adenoma operations (2%). Two (3%) nasoseptal flaps failed. Contributing factors for the 9 repair failures were BMI ≥ 30 (7/9), lack of buttress (4/9), grade 3 leak (4/9), and postoperative vomiting (4/9). Comparison of the epochs showed that grade 1–3 repair failures decreased from 6/143 (4.1%) to 3/141 (2.1%) and grade 1–3 meningitis rates decreased from 5 (3.5%) to 1 (0.7%) (p = 0.08). Prophylactic lumbar CSF drainage was used in only 4 cases (< 1%), was associated with a higher meningitis rate in grades 1–3 (25% vs 2%), and was discontinued in 2012. Comparison of the 2 epochs showed increase buttress use in the second, with use of a permanent buttress in grade 1 and 3 leaks increasing from 13% to 55% and 32% to 76%, respectively (p < 0.001), and use of autologous septal/keel bone as a permanent buttress in grade 1, 2, and 3 leaks increasing from 15% to 51% (p < 0.001).

Conclusions

A graded approach to skull base repair after endonasal surgery remains valid in the endoscopic era. However, the technique has evolved significantly, with further reduction of postoperative CSF leak rates. These data suggest that buttresses are beneficial for repair of most grade 1 and 2 leaks and all grade 3 leaks. Similarly, pedicled flaps appear advantageous for grade 3 leaks, while CSF diversion may be unnecessary and a risk factor for meningitis. High BMI should prompt an aggressive multilayered repair strategy. Achieving repair failure and meningitis rates lower than 1% is a reasonable goal in endoscopic skull base tumor surgery.

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.

Fetoscopic patch coverage of experimental myelomenigocele using a two-port access in fetal sheep

PURPOSE

This study aims to assess the feasibility and the effectiveness of a fetoscopic myelomeningocele (MMC) coverage using a sealed inert patch through a two-port access, in the sheep model.

METHODS

Forty-four fetuses underwent surgical creation of a MMC defect at day 75 and were divided into four groups according to the MMC repair technique, performed at day 90. Group 1 remained untreated. Group 2 had an open surgery using suture of the defect. Groups 3 and 4 underwent defect coverage using a Gore®-polytetrafluoroethylene patch secured with surgical adhesive (Bioglue®), with an open approach (group 3) and a fetoscopic one (group 4). Lambs were killed at term, and histological examinations were performed.

RESULTS

Fetoscopic patch coverage was achieved in all the lambs of group 4. All the fetuses of group 2 had a complete closure of the defect whereas only 38% in group 3 and 14% in group 4. Fetal loss rate seems to be lower in group 4 than in groups 2 and 3.

CONCLUSION

Fetoscopic coverage of MMC defect can be performed using a sealed patch through a two-port access, but the patch and glue correction may not be the ideal technique to repair fetal MMC.

Risk Factors and Management of Intraoperative Cerebrospinal Fluid Leaks in Endoscopic Treatment of Pituitary Adenoma: Analysis of 492 Patients

OBJECTIVES

To determine risk factors and management of intraoperative cerebrospinal fluid (CSF) leakage in endoscopic endonasal transsphenoidal pituitary adenoma surgery.

METHODS

We conducted a retrospective review of 492 patients who, between April 2012 and August 2015, underwent endoscopic endonasal transsphenoidal surgeries for resection of pituitary adenoma. A multivariate statistical analysis was performed to investigate the association of some risk factors with intraoperative CSF leakage. Intraoperative CSF leaks were classified as grade 0, no leak observed; grade 1, small leak without obvious diaphragmatic defect; grade 2, moderate leak; or grade 3, large diaphragmatic defect. Repair methods were based on the CSF leak grade.

RESULTS

Intraoperative CSF leakage occurred in 86 cases (17.5%). On univariate analysis, there were 3 factors associated with an increased intraoperative CSF leak rate: 1) repeat surgery (repeat 30.0% vs. primary 16.4%; P = 0.033), 2) consistency of the adenoma (tenacious, 27.3% vs. soft, 13.5%; P = 0.000), and 3) tumor size (22.0 ± 9.7mm vs. 25.4 ± 11.5 mm; P = 0.007). However, on multivariate analysis, only tumor consistency (P = 0.001; odds ratio, 2.379) and tumor size (P = 0.026; odds ratio, 1.032) were independently associated with intraoperative CSF leaks. In the 86 cases with intraoperative CSF leaks, the degree of intraoperative CSF leakage was categorized grade 1 in 30 cases, grade 2 in 25 cases, and grade 3 in 31 cases. Postoperative CSF leak repair failures occurred in 6 cases (1.2%).

CONCLUSIONS

Intraoperative CSF leaks have a propensity to occur in cases with fibrous or large tumors. Once an intraoperative leak is identified, our graded cranial base repair method is safe and reliable.

Endoscopic management of cerebrospinal fluid rhinorrhea

Cerebrospinal fluid (CSF) rhinorrhea occurs due to communication between the intracranial subarachnoid space and the sinonasal mucosa. It could be due to trauma, raised intracranial pressure (ICP), tumors, erosive diseases, and congenital skull defects. Some leaks could be spontaneous without any specific etiology. The potential leak sites include the cribriform plate, ethmoid, sphenoid, and frontal sinus. Glucose estimation, although non-specific, is the most popular and readily available method of diagnosis. Glucose concentration of > 30 mg/dl without any blood contamination strongly suggests presence and the absence of glucose rules out CSF in the fluid. Beta-2 transferrin test confirms the diagnosis. High-resolution computed tomography and magnetic resonance cisternography are complementary to each other and are the investigation of choice. Surgical intervention is indicated, when conservative management fails to prevent risk of meningitis. Endoscopic closure has revolutionized the management of CSF rhinorrhea due to its less morbidity and better closure rate. It is usually best suited for small defects in cribriform plate, sphenoid, and ethmoid sinus. Large defects can be repaired when sufficient experience is acquired. Most frontal sinus leaks, although difficult, can be successfully closed by modified Lothrop procedure. Factors associated with increased recurrences are middle age, obese female, raised ICP, diabetes mellitus, lateral sphenoid leaks, superior and lateral extension in frontal sinus, multiple leaks, and extensive skull base defects. Appropriate treatment for raised ICP, in addition to proper repair, should be done to prevent recurrence. Long follow-up is required before leveling successful repair as recurrences may occur very late.

Experiences with TachoSil® in microneurosurgery

BACKGROUND

We analyze our experience of using TachoSil® (Takeda Austria GmbH: Linz, Austria) in microneurosurgical procedures as a hemostat and also as a sealant to patch dural defects.

MATERIALS AND METHODS

Beginning on January 1, 2012, we prospectively analyzed 100 consecutive surgeries where TachoSil was used. The patient group included 58 women (58 %) and 42 men (42 %); the mean age was 52 years (range, 3-85 years). Indications for surgery included removal of the tumor (53 cases; 53 %), clipping of the cerebral arterial aneurysm (31 cases; 31 %), and treatment of other pathologies, including AVM (four cases; 4 %), cavernomas (four cases; 4 %), spinal tumor, and traumatic subdural hematoma. Patients received postoperative care according to local neurosurgical department protocol, including a postoperative CT scan after each craniotomy. Primary assessment of the wound took place during the hospital stay as well as at discharge or transfer to a rehabilitation unit. Mean follow-up time was 4 months (range, 1-12 months).

RESULTS

None of the patients developed postoperative hematoma after craniotomy or spinal procedure. At primary assessment during hospital stay, 93 patients (93 %) had had no wound-related problems over the normal course of healing. No case registered any liquor leak from the wound, and none of the patients showed any signs of allergic response related to TachoSil usage. At the last follow-up, 96 patients (96 %) experienced uneventful wound healing, and in four patients (4 %), superficial wound infection was successfully treated with oral antibiotics.

CONCLUSIONS

Our results indicate that TachoSil can serve in neurosurgical practice at no additional risks. TachoSil proved to be an effective hemostat, sealant, and adhesive in either cranial or spinal procedures.

Sealing of cerebrospinal fluid leakage during conventional transsphenoidal surgery using a fibrin-coated collagen fleece

The prevention of cerebrospinal fluid (CSF) leakage is a key feature of the transsphenoidal approach (TSA) to the pituitary fossa. Although fibrin-coated collagen fleece (Tachosil, Nycomed, Linz, Austria) is a powerful topical hemostatic agent whose usage is increasing in open neurosurgery, the use of Tachosil in TSA surgery has not yet gained wide clinical acceptance. We retrospectively evaluated whether the lone use of Tachosil without additional packing material or postoperative lumbar drainage was effective to prevent CSF leakage in TSA surgery in 101 patients. Additionally, we compared it to a conventional sellar closure technique in 54 patients. Only two (1.9%) of the patients in the Tachosil application group developed postoperative CSF rhinorrhea. No other postoperative complications occurred, including infection or material detachment. However, in the conventional packing group, five (9.3%) patients developed postoperative CSF rhinorrhea and one (1.9%) developed meningitis during the postoperative period. The mean length of postoperative hospital stay was significantly shorter in the Tachosil treatment group than in the standard closure group. These results may indicate that sellar repair using Tachosil can be effective to prevent CSF leakage after TSA surgery, and obviate the need for an autologous tissue graft or postoperative lumbar drainage.

Use of Tissue Glues in Endoscopic Pituitary Surgery: A Cost Comparison

Background:

Post-operative cerebrospinal fluid (CSF) leaks are a common complication of endoscopic pituitary surgery and account for a significant proportion of hospital costs associated with this procedure. Tisseel® is a tissue glue commonly used as an adjunct in dural repair but is not optimal for this purpose. DuraSeal® has several properties advantageous for dural repair but is not widely accepted in Canada partly due to its increased cost.

Objective:

A cost analysis of DuraSeal® versus Tisseel® in endoscopic pituitary surgery.

Methods:

A cost analysis was performed based on typical endoscopic pituitary surgery cases performed at our tertiary care institution. Operating room, hospital admission, and surgical sealant costs were obtained directly while estimates of patient recovery time and post-operative CSF leak rates were based on consensus values reported in the literature. Outcomes were reported for various possible clinical scenarios of sealant use.

Results:

In a model where surgical sealant is employed only in high-risk cases, use of DuraSeal® allows for a yearly cost savings of at least $4486.72. If surgical sealant is used in all cases, regular use of DuraSeal® versus Tisseel® either marginally reduces yearly costs or increases them by a maximum of $7619.25, depending on the case volume and estimated post-operative CSF leak rate.

Conclusion:

In most clinical scenarios, use of DuraSeal® in endoscopic pituitary surgery may reduce overall yearly hospital costs compared to Tisseel®.

The use of surgical sealants in the repair of dural tears during non-instrumented spinal surgery

PURPOSE

To compare the success in repair of dural tears (DTs) using two different surgical sealants in non-instrumented lumbar spinal surgery and evaluate the incidence of associated short- and long-term complications.

METHODS

Twenty-three patients undergoing non-instrumented spinal surgery with intraoperative DTs were included both retrospectively and prospectively in this study. External signs of CSF leakage, neurological deficits, and infection-related complications were investigated postoperatively. The persistence of low-back pain was also evaluated and postoperative MRI was performed in all patients. DTs were repaired intraoperatively using suture with or without a dural patch. Eleven patients received an application of fibrin glue (Tissucol(®); Baxter, Inc., IL, USA) and 12 patients received an application of bovine serum albumin glutaraldehyde surgical adhesive (BioGlue(®) Surgical Adhesive; CryoLife, GA, USA). These patients were followed up at 3 months and 1 year postoperatively.

RESULTS

Successful intraoperative DT repair was obtained in all cases. Three patients in the Tissucol group presented with CSF leakage in the early postoperative period. There were no complications observed in the patients treated with BioGlue. At 3-month follow-up, no incidences of neurological or infection-related complications were observed in either group. There was no statistically significant difference in VAS between the two treatment groups.

CONCLUSIONS

Intraoperative DTs can be easily repaired by many effective techniques. However, in our experience, the use of BioGlue is an effective adjunct to immediate dural repair, being comparable in terms of efficacy and safety to the use of fibrin glue, potentially decreasing the incidence of associated short- and long-term complications.

Risk factors for postoperative CSF leakage after elective craniotomy and the efficacy of fleece-bound tissue sealing against dural suturing alone: a randomized controlled trial

OBJECT

Cerebrospinal fluid leakage is an immanent risk of cranial surgery with dural opening. Recognizing the risk factors for this complication and improving the technique of dural closure may reduce the associated morbidity and its surgical burden. The aim of this paper was to investigate whether the addition of TachoSil on top of the dural suture reduces postoperative CSF leakage compared with dural suturing alone and to assess the frequency and risk factors for dural leakage and potentially related complications after elective craniotomy.

METHODS

The authors conducted a prospective, randomized, double-blinded single-center trial in patients undergoing elective craniotomy with dural opening. They compared their standard dural closure by running suture alone (with the use of a dural patch if needed) to the same closure with the addition of TachoSil on top of the suture. The primary end point was the incidence of CSF leakage, defined as CSF collection or any open CSF fistula within 30 days. Secondary end points were the incidence of infection, surgical revision, and length of stay in the intensive care unit (ICU) or intermediate care (IMC) unit. The site of craniotomy, a history of diabetes mellitus, a diagnosis of meningioma, the intraoperative need of a suturable dural substitute, and blood parameters were assessed as potential risk factors for CSF leakage.

RESULTS

The authors enrolled 241 patients, of whom 229 were included in the analysis. Cerebrospinal fluid leakage, mostly self-limiting subgaleal collections, occurred in 13.5% of patients. Invasive treatment was performed in 8 patients (3.5%) (subgaleal puncture in 6, lumbar drainage in 1, and surgical revision in 1 patient). Diabetes mellitus, a higher preoperative level of C-reactive protein (CRP), and the intraoperative need for a dural patch were positively associated with the occurrence of the primary end point (p = 0.014, 0.01, and 0.049, respectively). Cerebrospinal fluid leakage (9.7% vs 17.2%, OR 0.53 [95% CI 0.23-1.15], p = 0.108) and infection (OR 0.18 [95% CI 0.01-1.18], p = 0.077) occurred less frequently in the study group than in the control group. TachoSil significantly reduced the probability of staying in the IMC unit for 1 day or longer (OR 0.53 [95% CI 0.27-0.99], p = 0.048). Postoperative epidural hematoma and empyema occurred in the control group but not in the study group.

CONCLUSIONS

Dural leakage after elective craniotomy/durotomy occurs more frequently in association with diabetes mellitus, elevated preoperative CRP levels, and the intraoperative need of a dural patch. This randomized controlled trial showed no statistically significant reduction of postoperative CSF leakage and surgical site infections upon addition of TachoSil on the dural suture, but there was a significant reduction in the length of stay in the IMC unit. Dural augmentation with TachoSil was safe and not related to adverse events. Clinical trial registration no. NCT00999999 ( http://www.ClinicalTrials.gov ).

The endoscopic hemi-transseptal approach to the sella turcica: operative technique and case-control study

Background The hemi-transeptal (Hemi-T) approach was developed to facilitate a binasal two-surgeon endoscopic approach for sellar tumors, with preservation of the nasoseptal flap and selective mobilization for reconstruction. Methods A retrospective case-control study was performed comparing the Hemi-T approach with previously used methods of sellar exposure and reconstruction. Outcome measures included operative time and postoperative nasal morbidity. Results A total of 23 patients underwent the Hemi-T approach versus 42 in whom traditional exposure was performed. Operative time was significantly shorter using the Hemi-T technique (152.6 ± 56.8 versus 205.2 ± 61.3 minutes; p = 0.001), as was the length of hospital stay (3.3 ± 1.9 versus 5.4 ± 3.6 days; p = 0.004). There was no difference in the rates of intraoperative or postoperative cerebrospinal fluid leak, cartilage necrosis, septal perforation, or mucosal adhesions. Conclusion The Hemi-T approach facilitates binasal two-surgeon access to the sella without compromise of the pedicle during the extended sphenoidotomies and tumor removal. Operative time and nasal morbidity is not increased, and iatrogenic injury to the nasal cavity is minimized when a flap is not required.

Reconstructed bone chip detachment is a risk factor for sinusitis after transsphenoidal surgery

OBJECTIVES/HYPOTHESIS

Sphenoid sinusitis is a complication associated with endoscopic transsphenoidal pituitary surgery. Studies that address the relationship between methods of sellar defect reconstruction and postoperative sinusitis are rare. The purpose of this study was to investigate the incidence, the possible risk factors, and the causative pathogens of sphenoid sinusitis after endoscopic transsphenoidal pituitary surgery.

STUDY DESIGN

Prospective cohort study.

METHODS

We performed a prospective analysis of 182 patients with benign pituitary tumor who underwent endoscopic transsphenoidal pituitary surgery and sellar defect reconstruction with bone chip, from July 2008 through July 2011. All patients were followed up with nasal endoscopy for at least 6 weeks.

RESULTS

Fifty-seven (31.3%) patients developed postoperative sphenoid sinusitis. Comparing the sinusitis and nonsinusitis groups, we found that bone chip detachment was a significant risk factor for postoperative sinusitis, with a relative risk of 2.86 (64.1% vs. 22.4%). The most common pathogens present in cases of postoperative sinusitis were methicillin-sensitive Staphylococcus aureus, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus.

CONCLUSIONS

Regular follow-up with nasal endoscopy can prevent delayed diagnosis of postoperative sphenoid sinusitis. Culture-directed antibiotics with aggressive endoscopic debridement are an effective treatment for these patients. An optimal reconstruction strategy should be further developed to reduce bone chip detachment and secondary sinusitis.

The use of abdominal free fat for volumetric augmentation and primary dural closure in supratentorial skull base surgery: managing the stigma of a temporal defect

The most prominent stigma of supratentorial skull base surgery is the defect caused by wasting of the temporalis muscle by denervation, devascularization, or rotation of the muscle. Any of the above may lead to a unilateral temporal deformity informally referred to patients as "the divot in my head." Abdominal free fat grafting has been used by surgeons for years to close posterior fossa defects with excellent results. We present our experience using abdominal free fat grafts to improve cosmetic results and to prevent cerebrospinal fluid leaks in supratentorial skull base surgery. The basic technique and its benefits are described.

Primary closure of a cerebrospinal fluid fistula by nonpenetrating titanium clips in endoscopic endonasal transsphenoidal surgery: technical note

Postoperative cerebrospinal fluid (CSF) leakage is one of the most common and aggravating complications in transsphenoidal surgery. Although primary closure of the fistula would be the most desirable solution for an intraoperatively encountered CSF leak, it is difficult to achieve in such a deep and narrow operative field. In this article, the authors report endonasal endoscopic applications of no-penetrating titanium clips to repair a CSF fistula following tumor removal. The AnastoClip Vessel Closure System (VCS; LeMaitre Vascular, Boston, MA) was used for closure of a CSF fistula in endonasal transsphenoidal surgery. In all four patients, CSF leakage was successfully obliterated primarily with two to five clips. There was no postoperative CSF rhinorrhea or complications related to the use of the VCS. Metal artifact by the clips on postoperative images was tolerable. Primary closure of the fistula using the VCS was an effective strategy to prevent postoperative CSF leakage in transsphenoidal surgery. Future application can be expanded to reconstruction of the skull base dura via endonasal skull base approaches.

Clinical efficacy of radiation-sterilized allografts for sellar reconstruction after transsphenoidal surgery

OBJECTIVE

The aim of this study was to assess the safety and efficacy of radiation-sterilized allografts of iliac bone and fascia lata from cadaver specimens to repair skull base defects after transsphenoidal surgery.

METHODS

Between May 2009 and January 2010, 31 consecutive patients underwent endonasal transsphenoidal surgery and all patients received sellar reconstruction using allografts following tumor removal. The allografts were obtained from the local tissue bank and harvested from cadaver donors. The specimens used in our approach were tensor fascia lata and the flat area of iliac bone. For preparation, allografts were treated with gamma irradiation after routine screening by culture, and then stored at -70℃.

RESULTS

The mean follow-up period after surgery was 12.6 months (range, 7.4-16 months). Overall, postoperative cerebrospinal fluid (CSF) leaks occurred in three patients (9.7%) and postoperative meningitis in one patient (3.2%). There was no definitive evidence of wound infection at the routine postoperative follow-up examination or during re-do surgery in three patients. Postoperative meningitis in one patient was improved with the use of antibiotics and prolonged CSF diversion.

CONCLUSION

We suggest that allograft materials can be a feasible alternative to autologous tissue grafts for sellar reconstruction following transsphenoidal surgery under selected circumstances such as no or little intraoperative CSF leaks.

Study of dural suture watertightness: an in vitro comparison of different sealants

BACKGROUND

CSF leakages constitute a major complication of intradural procedures, especially for posterior fossa and skull base surgery. Dural suture watertightness is a decisive issue, and neurosurgeons routinely use different products to reinforce their dural closure. We have designed an experimental system capable of testing CSF leak pressure levels in order to compare two types of sutures in vitro and particularly four different sealants.

METHODS

Twenty-five fresh human cadaveric dural samples were removed and prepared for testing in a pressure chamber system connected to a hydraulic pressure motor. CSF leak levels were objectively registered. First, simple interrupted stitches were compared to running simple closure on 50-mm linear suture. Secondly, four sealants (two sealants/glues, Bioglue®, Duraseal®; two haemostatics, Tachosil®, Tissucol®) were tested. Statistical analysis was performed with paired Student's t-test.

RESULTS

No significant difference between interrupted closure and running suture was observed (p = 0.079). All sealants increased the watertightness of the suture significatively. However, comparison of the means of the differences for each product revealed large variations. In the conditions of our experiment, one sealant (Duraseal®) and one haemostatic (Tachosil®) seemed to show better results. We observed two different types of leakage: at the dura-sealant interface and through the sealant itself.

CONCLUSIONS

We have developed an experimental device capable of testing dural closure watertightness. Interrupted stitch suturing seemed no different from running simple closure. On the contrary, the sealants tested show different watertightness capacities.

Gasket seal closure for extended endonasal endoscopic skull base surgery: efficacy in a large case series

OBJECTIVE

To assess long-term efficacy of the gasket seal, a method for watertight closure of the cranial base using autologous fascia lata held in place by a rigid buttress, in a large case series.

METHODS

A prospectively acquired database of all endonasal endoscopic surgeries performed over a 5-year period at Weill Cornell Medical College starting in September 2005 was reviewed.

RESULTS

The gasket seal was used in 46 consecutive patients. Mean age was 53 years (range 7-83 years). All patients had extensive intracranial disease with a significant intraoperative cerebrospinal fluid (CSF) leak. Pathology included craniopharyngioma (39.1%), meningioma (23.9%), and pituitary adenoma (17.4%). After a mean follow-up of 28 months (range 3-63 months), two (4.3%) patients had a postoperative CSF leak. Excluding the patients with adenomas, the CSF leak rate was 5.2% (2 of 38 patients). One leak was controlled with reoperation, and the other was stopped with a lumbar drain (LD). The significance of pathology, type of approach, exposure of the ventricular system, use of fat graft, use of nasoseptal (NS) flap, and use of lumbar drain (LD) was examined, and none of these were significant predictors of postoperative CSF leak.

CONCLUSIONS

Gasket seal closure is a reliable long-term effective method for achieving watertight closure of the cranial base. It can be used in association with an intracranial fat graft, NS flap, LD, and tissue sealants. In this series, none of these other factors were significant predictors of postoperative CSF leak.

Polyethylene glycol (PEG) hydrogel dural sealant and collagen dural graft matrix in transsphenoidal pituitary surgery for prevention of postoperative cerebrospinal fluid leaks

Cerebrospinal fluid (CSF) rhinorrhea is the most common complication after transsphenoidal pituitary surgery. The authors compare their previous experience using an autologous fat graft and lumbar drain placement in 107 patients with their current technique of using a dural sealant and collagen matrix in 97 patients to prevent postoperative CSF leak after pituitary tumor resection. The failure rate for CSF leak repairs between the two groups was similar. The use of a dural sealant and collagen matrix, however, has the advantages of decreased length of hospital stay, decreased length of Intensive Care Unit stay, avoidance of the morbidity of an extra abdominal incision, and avoidance of the risks of lumbar CSF drainage.

Management and implications of intraoperative cerebrospinal fluid leak in transnasoseptal transsphenoidal microsurgery

BACKGROUND

Nonvascularized autologous grafts used for sellar reconstruction in transseptal transsphenoidal surgery are commonly applied in the setting of intraoperative cerebrospinal fluid (CSF) leak and have been shown to be effective in preventing postoperative complications.

OBJECTIVE

To assess the clinical implications of intraoperative CSF leak, to evaluate the efficacy of repair techniques using autologous nonvascularized materials, and to analyze the nature and timing of failures. These data may serve as a basis for assessing the utility of innovations in techniques and implant technologies.

METHODS

A review was conducted of 257 consecutive patients who underwent transsphenoidal surgery that was complicated by intraoperative CSF leak from 1995 to 2001. Sellar reconstruction was performed with autologous materials except in reoperations in which septal materials were not available; lumbar drain catheters were used selectively.

RESULTS

Six of the 257 patients (2.3%) developed postoperative CSF rhinorrhea occurring an average of 6.6 days after surgery. All 6 underwent reoperation, with 5 of 6 managed with operative lumbar drainage. Bacterial meningitis developed in 3 of 257 (1.2%). Worsening in visual function occurred in 8 of 257 (3.1%), with 1 of 257 (0.3%) suffering from permanent worsening of visual function. Additional surgery was performed in 2 of these patients, resulting in successful reversal of visual loss. Ten of 257 patients (3.9%) developed a subcutaneous hematoma at the fat graft harvest site, with 1 patient requiring surgical re-exploration.

CONCLUSIONS

Watertight closure of the sella with autologous materials is effective in preventing postoperative rhinorrhea. Complications specific to the technique include graft site hematoma (4%) and rare instances of visual loss caused by optic nerve compression.

Low-grade CSF leaks in endoscopic trans-sphenoidal pituitary surgery: efficacy of a simple and fully synthetic repair with a hydrogel sealant

BACKGROUND

Intra-operative CSF leak during endoscopic trans-sphenoidal surgery is not uncommon. Surgical repair with a variety of autologous grafts, rigid buttresses and CSF diversion techniques that add time and complexity have been reported.

OBJECTIVE

To describe a simple and purely synthetic closure for low-grade CSF leaks following endoscopic trans-sphenoidal pituitary surgery.

METHODS

A retrospective review of all endoscopic trans-sphenoidal surgery undertaken for pituitary pathology between 2005 and 2010 was carried out. The grade of CSF leak and success of graded repair was noted. Patients with no CSF leak (grade 0) had gelatin sponge placed in the tumour cavity. In those with low-grade CSF leak through small arachnoid defects (grade 1), repair was carried out using gelatin sponge and hydrogel sealant overlay. CSF diversion was not employed for low-grade CSF leaks.

RESULTS

Of the 255 endoscopic trans-sphenoidal surgeries, 158 (62%) had no leak (grade 0) and 74 (29%) had a low-grade leak (grade 1). Repairs in all cases were of grade 0, and all but two cases of grade 1 CSF leak were successful at a mean follow-up of 29 months. The 2 (2.7%) post-operative CSF leaks were seen within 6 weeks of surgery. Both cases were related to bouts of sneezing and were repaired using further trans-sphenoidal surgery and/or lumbar CSF diversion.

CONCLUSIONS

A simple purely synthetic repair of low-grade CSF leaks is described. This repair is safe and comparable in efficacy whilst avoiding the morbidity related to more complex sellar reconstructions previously described.

Challenging reconstructive techniques for skull base defect following endoscopic endonasal approaches

OBJECTIVE

We assessed the outcomes of various reconstructive methods for skull base defect after endoscopic endonasal approaches (EEA) depending on the degree of intraoperative cerebrospinal fluid (CSF) leaks.

METHODS

Between Jan. 2008 and Sep. 2009, 122 consecutive patients underwent 124 EEA for sellar and extra-sellar lesions. Intraoperative CSF leaks were classified as grade 0, no intraoperative CSF leak; grade 1, low output; and grade 2, high-output based on the degree of CSF leakage and size of opening in the arachnoid membrane (<5 or ≥5 mm).

RESULTS

Postoperative CSF leaks or meningitis occurred in 13 of 124 cases (10.5%). In 77 patients with grade 0, there was no postoperative CSF leak. Among 20 patients with grade 1 CSF leaks, four patients developed meningitis or postoperative CSF leak. Postoperative CSF leaks occurred in nine of 26 patients (34.6%) with grade 2 leaks. Comparison of reconstructive methods revealed that gasket-seal method provided better control of CSF leaks than free-fat graft in patients with grade 2 leaks (11.8% vs. 66.7%, p = 0.028). However, in grades 0 and 1, we found no difference among the various reconstructive methods.

CONCLUSION

The selection of reconstructive methods for skull base defects should be determined by the degree of CSF leaks. Although grade 0 or 1 leak requires relatively conservative management such as simple closure or free-tissue grafting, a more aggressive reconstructive technique is required to prevent postoperative complication in grade 2 CSF leak.

Surgical site infection associated with the use of bovine serum albumine-glutaraldehyde surgical adhesive (BioGlue) in cranial surgery: a case-control study

PURPOSE

To enhance the water tightness of dura mater closure in cranial surgery, an organic glue called BioGlue was used in our neurosurgical department between January 2006 and June 2007. During this period of time, we noticed an important increase in the surgical site infection (SSI) incidence. We conducted a case-control study to identify risk factors for these infections. Our objective was to test the hypothesis that BioGlue was one of the risk factors.

METHODS

Cases with infection were defined retrospectively. We included two controls per case. Study data were age, sex, time of year, in stay hospital preoperative time, length of surgery, type of surgery, surgeon, use of BioGlue, and use of duraplasty. We first performed a univariate analysis and then the significant variables were introduced in a logistic regression model.

RESULTS

Thirty patients were defined as cases (60 controls). In multivariate analysis, risk factors were young age (p = 0.04), extended operative length (p = 0.02) and the use of BioGlue (p = 0.007). The combined use of BioGlue and Neuropatch appeared to be a significant risk factor for SSI (p = 0.002).

CONCLUSIONS

BioGlue seems to increase the risk of SSI for patients who underwent craniotomy, especially when associated with synthetic dural graft. BioGlue triggers an intense inflammatory response, which causes wound breaches allowing bacteria to spread down in the wound, and then creates an ideal environment for bacterial growth.

Management of intra-operative cerebrospinal fluid leak following endoscopic trans-sphenoidal pituitary surgery

OBJECTIVE

Cerebrospinal fluid leakage is the most common complication of endoscopic trans-sphenoidal pituitary surgery. However, there is no uniformly accepted way of managing this complication when it occurs intra-operatively. This paper describes a quick, simple technique, involving layered fibrin glue and gelatin sponge, which does not compromise post-operative patient follow up.

METHOD

Retrospective review of all endoscopic pituitary surgery cases conducted at a single institution since the introduction of this technique in 2002.

RESULTS

A total of 120 endoscopic pituitary operations were performed (96 primary procedures and 24 revisions). All intra-operative cerebrospinal fluid leaks were managed using the described method, with a failure rate of 3.6 per cent. The overall post-operative leakage rate was 1.7 per cent.

CONCLUSION

This simple, conservative technique avoids the need for further dissection and the use of non-absorbable foreign material, and has a low incidence of post-operative cerebrospinal fluid leakage.

The endoscopic, endonasal, transmaxillary transpterygoid approach to the pterygopalatine fossa, infratemporal fossa, petrous apex, and the Meckel cave

Object

In this paper the authors' goal was to present their clinical experience with lesions of the pterygopalatine fossa, infratemporal fossa, lateral sphenoid sinus, cavernous sinus, petrous apex, and Meckel cave using simple and extended endoscopic transpterygoid approaches to the lateral skull base.

Methods

Simple and expanded endoscopic transpterygoid approaches were performed in a series of 13 patients with varying pathology that included lateral sphenoid sinus encephaloceles, benign and malignant sinonasal tumors, and lesions of neural origin.

Results

A gross-total resection was achieved in 5 of 9 patients, while a subtotal resection for tissue diagnosis and cytoreduction prior to further adjuvant treatment was performed in the remaining patients. Sphenoid sinus encephaloceles were successfully repaired via a transpterygoid approach in all 4 patients. The skull base defect was reconstructed using a multilayered closure. One patient developed a postoperative CSF leak, which was successfully treated conservatively. The mean follow-up time was 16 months. Five patients complained of recurrent sinusitis. One patient experienced xerophthalmia and palate numbness. Three patients had died by the time of this report. Two patients died of unrelated causes. The third patient died of progression of an aggressive pterygopalatine osteosarcoma despite undergoing cytoreductive surgery and adjuvant chemotherapy.

Conclusions

An endoscopic transpterygoid approach is a minimally invasive endoscopic approach for lesions located or extending to the pterygopalatine fossa, infratemporal fossa, petrous apex, Meckel cave, and other regions of the paramedian skull base.

Bitemporal hemianopia arising from a suprasellar craniopharyngioma

BACKGROUND

Craniopharyngiomas are uncommon intracranial tumors that arise from remnants of the embryonic craniopharyngeal duct. Although benign in nature, craniopharyngiomas can contribute to significant morbidity. When located near critical structures such as the optic chiasm, pituitary, and hypothalamus, craniopharyngiomas have the potential to cause severe visual, neurological, and endocrine deficits.

CASE REPORT

A 61-year-old white man presented for an eye examination, complaining of acute peripheral visual field loss in his left eye. Automated threshold visual field testing found a bitemporal hemianopia with spared fixation in his right eye and split fixation in his left eye. Subsequent neuroimaging found a space-occupying suprasellar lesion that was producing substantial optic chiasm compression. Transsphenoidal resection was used to excise the mass. Histologic examination established the diagnosis of a craniopharyngioma. Postoperative complications included cerebrospinal rhinorrhea, hypertropia, and exotropia.

CONCLUSION

To facilitate early diagnosis and treatment, eye care professionals should be aware that craniopharyngiomas can present with decreased visual acuity and bitemporal hemianopia. Visual deficits can arise from both the aggressive nature of craniopharyngiomas as well as the therapeutic intervention. Patients treated for craniopharyngiomas are at risk for recurrence and need to be followed up on a long-term basis.

A pilot study of fat allograft transplantation in immunocompetent rabbits for potential neurosurgical applications

OBJECT

The authors investigated the feasibility of using fat allografts (chemically treated to reduce the host immune response) for neurosurgical applications.

METHODS

Subcutaneous fat specimens collected from New Zealand White rabbits were treated with DNAse I and sodium deoxycholate to reduce immunogenicity before subcutaneous, midscapular implantation in immunocompetent recipient rabbits. Allograft incorporation and the host-allograft response were examined at 1, 6, and 11 weeks by histopathological analysis. Control specimens of autograft and untreated fat allograft implants were examined for comparison.

RESULTS

The host immune response was markedly reduced in the region around the chemically treated fat allografts when compared with untreated allografts, and was similar to the tolerant host response to autografts.

CONCLUSIONS

Based on their results, the authors suggest that fat allografts processed for reduced immunogenicity may be a convenient, viable alternative for neurosurgical applications.

A New Porcine Skull Base Model

OBJECTIVES: Fibrin glue is used in addition to grafts and flaps to repair cerebrospinal (CSF) leaks. We designed a porcine model to test the hypothesis that fibrin glue increases biomechanical strength.

STUDY DESIGN: A randomized experimental animal study.

METHODS: Ten pigs underwent craniotomy with creation of a fistula through the cribriform plate into the nasal cavity. CSF leaks were endoscopically confirmed and repaired using pericranial grafts. The animals were randomized into a fibrin glue group (n = 5) and a control group (n = 5). Seven days later, endoscopic examination assessed for CSF leaks. The skull bases were harvested and examined for the degree of graft adherence (graded I-V) and subjected to burst pressure testing and histopathological analysis.

RESULTS: Eight animals survived, four in each group. There were no CSF leaks in the fibrin glue group and one in the control group. The fibrin glue group showed greater graft adherence ( P = 0.029) and higher burst pressures (13.8 ± 5.4 vs 4.6 ± 3.1 psi, P = 0.021). Histopathological analysis revealed no difference in inflammation and bone remodeling.

CONCLUSIONS: The porcine model is a good model for anterior skull base defects. The model confirmed that fibrin glue reduces the rate of CSF leak by improving graft adherence and strength of repair.

Pituitary tumors: our experience in the prevention of postoperative cerebrospinal fluid leaks after transsphenoidal surgery

The objective was to analyze the management of intraoperative CSF leaks in transsphenoidal surgeries to prevent postoperative cerebrospinal fluid (CSF) leaks. Sixty-three pituitary tumors were operated by transnasal approach. In presence of arachnoidal opening, a fat graft was placed into the sellar cavity, followed by collagen sponge layer and fibrin glue. The sphenoid sinus was also packed with fat graft and collagen sponge. An external CSF lumbar drainage was kept for 2-4 days. The variables analyzed were: intraoperative and postoperative CSF leaks, procedures, and related complications. The overall incidence of postoperative CSF leak was 1.5%. Twenty patients (31.7%) had intraoperative arachnoidal opening, 5% of whom had postoperative CSF leak. There were no reoperations because of CSF leak, and no secondary intrasellar arachnoidoceles. Mean follow-up was 3.6 years. The preventive treatment had good results and there were no complications related to the intervention strategy, encouraging us to continue performing this simple, effective, and inexpensive procedure.

The endonasal microscopic approach for pituitary adenomas and other parasellar tumors: a 10-year experience

THE DIRECT ENDONASAL transsphenoidal approach to the sella with the operating microscope was initially described more than 20 years ago. Herein, we describe the technique, its evolution, and lessons learned over a 10-year period for treating pituitary adenomas and other parasellar pathology. From July 1998 to January 2008, 812 patients underwent a total of 881 operations for a pituitary adenoma (n = 605), Rathke's cleft cyst (n = 59), craniopharyngioma (n = 26), parasellar meningioma (n = 23), chordoma (n = 18), or other pathological condition (n = 81). Of these, 118 operations (13%) included an extended approach to the suprasellar, infrasellar/clival, or cavernous sinus regions. Endoscopic assistance was used in 163 cases (19%) overall, including 36% of the last 200 cases in the series and 18 (72%) of the last 25 extended endonasal cases. Surgical complications included 19 postoperative cerebrospinal fluid leaks (2%), 6 postoperative hematomas (0.7%), 4 carotid artery injuries (0.4%), 4 new permanent neurological deficits (0.4%), 3 cases of bacterial meningitis (0.3%), and 2 deaths (0.2%). The overall complication rate was higher in the first 500 cases in the series and in extended approach cases. Major technical modifications over the 10-year period included increased use of shorter (60-70 mm) endonasal speculums for greater instrument maneuverability and visualization, the micro-Doppler probe for cavernous carotid artery localization, endoscopy for more panoramic visualization, and a graded cerebrospinal fluid leak repair protocol. These changes appear to have collectively and incrementally made the approach safer and more effective. In summary, the endonasal approach provides a minimally invasive route for removal of pituitary adenomas and other parasellar tumors.

A simple and direct pre-embedding technique for ultrastructure of scarce biological specimens

A simple and rapid technique for pre-embedding scarce biological specimens for Transmission electron microscopy (TEM) is reported. It is based on pre-embedding biological samples in bovine serum albumin (BSA) and bis-acrylamide (BA), cross-linked and polymerized with paraformaldehyde, glutaraldehyde, ammonium persulfate and Temed. Pre-embedding in BSA and BA offers several advantages over traditional pre-embedding techniques for TEM including the ability to visualize the sample and a more resistant matrix. This results in more reproducible and consistent analysis. It can be applied to tissues, cells, and subcellular structures handled as pellets or suspensions. In addition, use of the pre-embedding matrix for light microscopy is reported. The ability to pre-embed scarce biological specimens efficiently and reproducibly provides a valuable way to study and characterize cytological tissues such as biopsies or cystic and amniotic fluid cells.