Endoscopic repair of anterior or middle skull base cerebrospinal fluid leaks after tumour resection

Endoscopic Endonasal Skull Base Surgery Complication Avoidance: A Contemporary Review

The endoscopic endonasal approach (EEA) provides a direct trajectory to ventral skull base lesions, avoidance of brain retraction, and clear visualization of cranial nerves as they exit skull base foramina. Despite these benefits, the EEA is not without complications. Here, we review published literature highlighting complications associated with the EEA including cerebrospinal fluid (CSF) leak, cranial nerve (CN) dysfunction, pituitary gland dysfunction, internal carotid artery (ICA) injury, infection, and others; we place special emphasis on discussing the prevention of these complications. As widespread adoption of the EEA continues, it becomes critical to educate surgeons regarding potential complications and their prevention while identifying gaps in the current literature to guide future research and advances in clinical care.

A New Technique for the Endoscopic Reconstruction of Skull Base Defects Using Multiple-balloon Catheters

Cerebrospinal fluid (CSF) leakage is a major complication following endoscopic endonasal skull base surgery. Various skull base reconstruction methods are available, and the use of a vascularized nasoseptal flap (NSF) in skull base reconstruction has greatly contributed to a decrease in the CSF leak rate. A balloon catheter such as a sinus balloon or a Foley catheter is often used to support an NSF; however, in cases wherein nasal and/or paranasal structures supporting the balloon are lacking following the surgery, the NSF is not properly fixed and postoperative CSF leak may occur. Here we introduce a new technique of using multiple-balloon catheters to fix an NSF in such cases and provide the results of our analysis of the new technique's efficacy. Eight patients who underwent endonasal endoscopic surgery for the following cases were included: olfactory neuroblastoma (n = 6), recurrent craniofacial meningioma (n = 1), and recurrent chordoma (n = 1). After tumor resection, multilayered reconstruction with vascularized NSF was performed. Given that the Foley catheter was not stable to fix the flap in each case, we used an additional nasal catheter to support the Foley catheter. No complications such as postoperative CSF leak and necrosis of the vascularized flap were observed. These results suggest that the multiple-balloon catheter technique is a useful method for fixing the NSF to the skull base even when nasal cavity structures are missing due to surgical removal.

Skull base repair following endonasal pituitary and skull base tumour resection: a systematic review

PURPOSE

Postoperative cerebrospinal fluid rhinorrhoea (CSFR) remains a frequent complication of endonasal approaches to pituitary and skull base tumours. Watertight skull base reconstruction is important in preventing CSFR. We sought to systematically review the current literature of available skull base repair techniques.

METHODS

Pubmed and Embase databases were searched for studies (2000-2020) that (a) reported on the endonasal resection of pituitary and skull base tumours, (b) focussed on skull base repair techniques and/or postoperative CSFR risk factors, and (c) included CSFR data. Roles, advantages and disadvantages of each repair method were detailed. Random-effects meta-analyses were performed where possible.

RESULTS

193 studies were included. Repair methods were categorised based on function and anatomical level. There was absolute heterogeneity in repair methods used, with no independent studies sharing the same repair protocol. Techniques most commonly used for low CSFR risk cases were fat grafts, fascia lata grafts and synthetic grafts. For cases with higher CSFR risk, multilayer regimes were utilized with vascularized flaps, gasket sealing and lumbar drains. Lumbar drain use for high CSFR risk cases was supported by a randomised study (Oxford CEBM: Grade B recommendation), but otherwise there was limited high-level evidence. Pooled CSFR incidence by approach was 3.7% (CI 3-4.5%) for transsphenoidal, 9% (CI 7.2-11.3%) for expanded endonasal, and 5.3% (CI 3.4-7%) for studies describing both. Further meaningful meta-analyses of repair methods were not performed due to significant repair protocol heterogeneity.

CONCLUSIONS

Modern reconstructive protocols are heterogeneous and there is limited evidence to suggest the optimal repair technique after pituitary and skull base tumour resection. Further studies are needed to guide practice.

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.

Radiofrequency Coblation-Assisted Resection of Skull Base Neoplasms Using an Endoscopic Endonasal Approach

OBJECTIVES

We describe our early experiences with resecting skull base tumors using a radiofrequency ablation-assisted endoscopic endonasal approach. Ninety-seven patients with skull base tumors who were admitted to the Otorhinolaryngology department at Shanghai Jiaotong University Affiliated Shanghai Sixth People's Hospital between January 2014 and December 2016 were operated on using a radiofrequency ablation-assisted endoscopic endonasal approach. Complete resection was achieved in all patients. This paper describes the operative technique and presents the degree of resection, complications, and early clinical outcomes.

METHODS

We investigated the safety and feasibility of the technique and assessed preliminary treatment outcomes.

RESULTS

No patients experienced a new neurological deficit, cerebrospinal fluid leak, or meningitis after surgery. No deaths related to skull base tumors were observed during the follow-up period (14-50 months). The volume of intraoperative blood loss was 100-1,200 mL (median 350 mL), the duration of operation was 40-510 min (median 180 min), and the hospital stay was 6-65 days (median 18).

CONCLUSIONS

Our limited experience indicates that this technique is feasible and safe for complete resection of some skull base tumors in selected cases and in the future will have an increasing role to play in endoscopic sinonasal and skull base tumor dissection.

[Tactics of reconstructive closure of basal defects after resection of midline tumors of the anterior skull base (a literature review)]

The purpose of this review is to analyze the techniques used to reconstruct midline defects in the anterior skull base after transcranial and endoscopic endonasal resection of skull base tumors. We provide brief information on the technique for preparing various flaps, indications and contraindications, and advantages and disadvantages. We analyze the international experience in the use of vascularized and non-vascularized flaps as well as the existing algorithms for reconstruction of complex defects of the midline structures of the skull base. The literature data demonstrate the absence of a conventional tactics of reconstructive closure of the discussed defects. To resolve this issue, a meta-analysis in combination with an original prospective study is required.

A Systematic Review of Secondary Cerebrospinal Fluid Leaks

Background

Secondary cerebrospinal leaks (CSF) are leaks that recur after an initial endoscopic repair of CSF leaks. Identification of characteristics that could predict secondary leaks may allow surgeons to plan repairs with the knowledge that these defects are more likely to fail.

Objective

To identify characteristics that could predict secondary CSF leaks.

Methods

A search of all studies that reported outcomes after endoscopic repair of CSF leaks was conducted by using medical literature data bases. Studies with the following criteria were included: written in the English language, secondary CSF leaks after primary repair, and assessment of success of fistula repair. Data extracted included the etiology of the leak, site of the leak, reconstructive materials used, and success of the repair.

Results

Ninety-four studies, from 1988 to 2015, with a total of 3149 primary CSF leaks were included. Sixty-three studies (67%) had a success rate of ≥80%; 77 studies (82%) had secondary leak rates of <40%. For 88 of the 94 studies (94%), the success rate after secondary repair improved to 81.0–100%. Of 48 studies that included leaks of more than one site, the sphenoid was the most common site of leak in 26 studies (55%), the ethmoid was the most common site in 16 studies (34%), and the cribriform was the most common site in 11 studies (23%).

Conclusion

The rate of secondary CSF leaks was low due to advances in endoscopic repair techniques. Spontaneous and iatrogenic CSF leaks were more likely to recur, especially without adequate control of underlying factors, such as increased intracranial pressure and obesity. Further studies with consistent reporting are required for more definitive conclusions about secondary CSF leaks.

Endoscopic Endonasal Anterior Skull Base Surgery: A Systematic Review of Complications During the Past 65 Years

BACKGROUND

Endoscopic skull base surgery is becoming more popular as an approach to the anterior skull base for tumors and cerebrospinal fluid (CSF) fistulae. It offers the advantages of better cosmesis and improved quality of life after surgery. We reviewed the complication rates reported in the literature.

METHODS

A literature search was performed in the electronic database Ovid MEDLINE (1950 to August 25, 2015) with the search item "([Anterior] AND Skull base surgery) AND endoscopic."

RESULTS

We identified 82 relevant studies that included 7460 cases. An average overall complication rate of 17.1% (range 0%-68.0%) and a mortality rate of 0.4% (0%-10.0%) were demonstrated in a total of 82 studies that included 7460 cases. The average CSF leak rate for all studies was 8.9% (0%-40.0%) with meningiomas and clival lesions having the greatest CSF leak rates. The most frequent benign pathology encountered was pituitary adenomas (n = 3720, 49.8% of all cases) and the most frequent malignant tumor was esthesioneuroblastoma (n = 120, 1.6% of all cases). Studies that included only CSF fistula repairs had a lower average total complication rate (12.9%) but a greater rate of meningitis compared with studies that reported mixed pathology (2.4% vs. 1.3%). A trend towards a lower total complication rate with increasing study size was observed.

CONCLUSIONS

The endoscopic approach is an increasingly accepted technique for anterior skull base tumor surgery and is associated with acceptable complication rates. Increasing experience with this technique can decrease rates of complications.

Endoscopic repair of cerebrospinal fluid rhinorrhoea

GOAL

The purpose of this review was to look at the success rate of transnasal endoscopic repair of CSF rhinorrhoea and the impact of patient factors, repair techniques and adjuvant treatment.

MATERIAL AND METHODS

A literature search was performed on PubMed, Medline and Cochrane Central databases, independently by two of the authors, of all studies reporting the outcomes of CSF rhinorrhoea repair, published until the 1st June 2014, using keywords Cerebrospinal fluid leak, CSF leak, CSF fistula, CSF leak or fistula repair, endoscopic sinus surgery or ESS complications. Sixty-seven papers were included for the review.

RESULT

The repair of CSF rhinorrhoea has rapidly evolved over the past 30 years. Prior to the advent of the endoscopic approach, craniotomy was used for repairs, which carried a variable success rate and morbidity. More recently, there have been several case series and reports that describe various endoscopic methods and materials for repair, with mean success rate of 90% (range: 60-100%). The most common site of CSF leak is the ethmoid roof/cribriform plate region. Traumatic CSF leak, in particular iatrogenic, is still the most common cause. Imaging with CT and MRI remains the gold standard for localisation of CSF leaks. The sphenoid sinus is the most common location for CSF leak repair failure. Lumbar drains and antibiotics are used as adjuvant therapy to endoscopic repair, but their benefits are not clear; intrathecal fluorescein can be used to aid location of CSF leak, but should be reserved for more complex cases. Further work into graft materials used and adjuvant treatment is needed to make any meaningful conclusions about their efficacy.

CONCLUSION

The literature demonstrates that endoscopic repair of CSF rhinorrhoea is safe and effective, with a very low complication rate. It has almost completely replaced the older open techniques.

Endoscopic Endonasal Repair of Sphenoid Sinus Cerebrospinal Fluid Leaks: Our Experience

Endoscopic endonasal approaches are becoming increasingly popular over transcranial approaches for repair of cerebrospinal leak defects. Sphenoid sinus CSF leaks pose a significant challenge and carry the risk of life-threatening intracranial complications. Their management depends upon identifying the leak using imaging techniques followed by intraoperative endoscopic localization. Our experience in the endoscopic endonasal management of sphenoid sinus CSF leaks is reported in this paper.

Sandwich grafting technique for endoscopic endonasal repair of cerebrospinal fluid rhinorrhoea

The surgical management of cerebrospinal fluid (CSF) rhinorrhoea has changed significantly after the introduction of functional endoscopic sinus surgery. The clear anatomical exposure of the roof of the nasal and paranasal sinus cavities by the endoscope offers the surgeon a golden chance to identify the area of CSF leak, and thus enables one to adequately plan the management. The aim of this work is to evaluate the use of facia lata sandwich graft technique for endoscopic endonasal repair of CSF rhinorrhoea. Forty patients with CSF rhinorrhoea were treated endoscopically using 2 layers of facia lata (underlay and onlay) interposed with a layer of septal cartilage or conchal bone in-between (sandwich technique) for repair. Fifty-five percent of cases were regarded as spontaneous CSF leaks with no obvious cause, 30% following head injury and 15% were iatrogenic. The ethmoidal roof was the commonest location of CSF leak (60%) followed in frequency by the cribriform plate and the sphenoid sinus (20% each). Follow-up period was 12-24 months. We have achieved a 95% success rate in managing CSF leaks in our 40 patients in the first attempt repair and 100% success rate after second attempt repair. Endoscopic endonasal repair of CSF leaks is quite safe and effective procedure with high success rate and avoid the morbidity associated with craniotomy. Using the three-layer, sandwich-grafting technique of facia lata further adds more security to the sealing of CSF and augments the results of repair.