The application of nasoseptal "rescue" flap technique in endoscopic transsphenoidal pituitary adenoma resection

Validity of the flap risk score in predicting nasoseptal flap use after endoscopic transsphenoidal pituitary mass resection

Introduction

There remains a paucity of literature examining the decision algorithm for use of nasoseptal flap (NSF) after endoscopic endonasal approaches (EEA) to pituitary adenoma resection. In 2018, we published the first ever flap risk score (FRS) to predict the use of NSF. We present here a validity study examining the FRS as applied to our center.

Methods

A retrospective review was completed of consecutive patients undergoing EEA from January 2015 to March 2021. The sensitivity, specificity, and predictive value of the FRS were calculated. A multivariate logistic model was used to determine the relative weight imaging characteristics in predicting need for NSF. The relative weighting of the FRS was then re-optimized.

Results

A total of 376 patients underwent EEA for pituitary adenoma resection, with 113 (30.1%) requiring NSF. The FRS had a sensitivity and specificity of 43.4% and 94.7%, respectively. Sphenoid sinus extension increased the odds of needing a NSF equivalent to 19 mm of tumor height, as opposed to 6 mm in the original 2018 cohort. The re-optimized model had sensitivity and specificity of 79.6% and 76.4%, respectively.

Conclusion

We present a validity study examining the utility of FRS in predicting the use of NSF after EEA for pituitary adenoma resection. Our results show that while FRS is still predictive of the need for NSF after EEA, it is not as predictive now as it was for its original cohort. Therefore, a more comprehensive model is necessary to more accurately stratify patients' preoperative risk for NSF.

Effects of Endoscopic Sinus Surgery on Olfactory Function

PURPOSE OF REVIEW

To review the effects of endoscopic sinus surgery and endonasal approaches to the skull base on olfaction.

RECENT FINDINGS

Advancements in endonasal endoscopic approaches to the sinuses and skull base allow for direct treatment of a variety of sinonasal and skull base diseases. However, these extended approaches will often require manipulation of normal anatomical structures and the olfactory neuroepithelium. Depending on the planned procedure and extent of disease, the prognosis of olfactory perception can vary significantly among patients. Endoscopic sinonasal surgical procedures may impact olfaction. Optimizing olfactory function requires proper surgical techniques, gentle handling of tissue, and perioperative care. Surgeons must discuss objectives and manage patient expectations. Routine olfactory assessment is crucial in surgical work-up and follow-up. Preserving anatomical structures while addressing the obstruction of the olfactory cleft helps to prevent decreased olfactory threshold. However, smell identification and discrimination do not always correlate with sinonasal anatomy.

Evaluation of the Gross Total Resection Rate of Suprasellar Pituitary Macroadenomas with and without the Removal of the Tuberculum Sellae Bone

OBJECTIVE

Improving the gross total resection (GTR) rate of suprasellar pituitary macroadenomas (SPMAs) using the pure endoscopic endonasal transsphenoidal approach (EETA) has been a long-standing focus of neurosurgeons. This study was aimed at evaluating the influences of the removal of the tuberculum sellae bone (TSB) without opening the dura of the tuberculum sellae on the GTR rate of SPMAs via the EETA.

METHODS

We retrospectively analyzed medical reports of patients with SPMAs who underwent EETA between February 2015 and November 2020. Data on clinical manifestations, endocrinologic types, imaging features (Hardy classification, morphology, and texture), clinical outcomes, and TSB removal status were collected. All patients were followed up for 6 months postoperatively.

RESULTS

Seventy-eight patients were enrolled in our study. The GTR rates of the TSB removal group (45/78, 57.7%) and nonremoval group (33/78, 42.3%) were 80.0% (36/45) and 57.6% (19/33), respectively. Univariate logistic regression analysis found that the removal of TSB, rounded morphology, and low Hardy classification were correlated with higher GTR rates. Multiple logistic regression analysis indicated that even after adjusting for tumor types and imaging features, the removal of TSB had an independent effect on the GTR rate (odds ratio, 7.6; 95% confidence interval, 1.8-31.6; P = 0.005). The incidence rates of postoperative cerebrospinal fluid leakage and diabetes insipidus were not significantly different between the TSB removal group and TSB nonremoval group.

CONCLUSIONS

TSB removal using EETA without opening the tuberculum sellae dura improves the GTR rate of SPMAs without increasing the incidence of postoperative complications.

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.

Cerebrospinal Fluid Leak after Transsphenoidal Surgery: A Systematic Review and Meta-analysis

Background Cerebrospinal fluid (CSF) leak is widely recognized as a challenging and commonly occurring postoperative complication of transsphenoidal surgery (TSS).

The primary objective of this study is to benchmark the current prevalence of CSF leak after TSS in the adult population.

Methods The authors followed the PRISMA guidelines. The PubMed, Embase, and Cochrane Library databases were searched for articles reporting CSF leak after TSS in the adult population. Meta-analysis was performed using the Untransformed Proportion metric in OpenMetaAnalyst. For two between-group comparisons a generalized linear mixed model was applied.

Results We identified 2,408 articles through the database search, of which 70, published since 2015, were included in this systematic review. These studies yielded 24,979 patients who underwent a total of 25,034 transsphenoidal surgeries. The overall prevalence of postoperative CSF leak was 3.4% (95% confidence interval or CI 2.8–4.0%). The prevalence of CSF leak found in patients undergoing pituitary adenoma resection was 3.2% (95% CI 2.5–4.2%), whereas patients who underwent TSS for another indication had a CSF leak prevalence rate of 7.1% (95% CI 3.0–15.7%) (odds ratio [OR] 2.3, 95% CI 0.9–5.7). Patients with cavernous sinus invasion (OR 3.0, 95% CI 1.1–8.7) and intraoperative CSF leak (OR 5.9, 95% CI 3.8–9.0) have increased risk of postoperative CSF leak. Previous TSS and microscopic surgery are not significantly associated with postoperative CSF leak.

Conclusion The overall recent prevalence of CSF leak after TSS in adults is 3.4%. Intraoperative CSF leak and cavernous sinus invasion appear to be significant risk factors for postoperative CSF leak.

Modified Nasoseptal Rescue Flap Technique for Pituitary Adenoma Resection via Endoscopic Endonasal Approach

ABSTRACT

Nasoseptal rescue flap (NSRF), which preserves the pedicle of the flap and is harvested as a nasoseptal flap (NSF) when intraoperative leakage of cerebrospinal fluid (CSF) occurs, is an alternative strategy for skull base reconstruction in patients with pituitary adenoma resection via an endoscopic endonasal approach. However, in practice, the original NSRF technique cannot meet the needs during operation. Therefore, the authors aimed to describe a modified NSRF technique for the resection of pituitary adenoma via endoscopic endonasal approach and to examine its utility and outcomes. The authors retrospectively analyzed the medical records of 87 consecutive patients with pituitary adenoma who underwent endoscopic endonasal surgery performed using NSRF technique from September 2019 to August 2020. Data on intraoperative CSF leakage, NSF conversion rate, and reconstruction-related complications were analyzed. The average age of patients was 50.1 years (men, 50.5%). Twenty-five cases of intraoperative CSF leakage were observed: 23 cases of low-flow CSF leakage and two cases of high-flow CSF leakage. NSRF was converted to NSF in 11 cases. Two patients experienced postoperative CSF leakage after reconstruction without NSF and required unplanned reoperation to rebuild the skull base with NSF. In conclusion, this modified NSRF utilized a minimally invasive way to provide sufficient surgical corridor without the need for pedicle retraction, and it can be effectively converted to an NSF for skull base reconstruction in patients with pituitary adenoma.

Sellar Floor Bone Flap With a Pedicled Nasoseptal Flap in Endoscopic Transnasal Pituitary Adenoma Surgery

OBJECTIVE

To explore the clinical effect of sellar floor bone flap with a pedicled nasoseptal flap in endoscopic transnasal pituitary adenoma surgery for skull base reconstruction.Method: This was a retrospective clinical analysis of 30 patients with pituitary adenoma operated by the same neurosurgical team from June 2015 to June 2018. All patients were diagnosed with pituitary adenoma by pituitary magnetic resonance imaging, and the authors confirmed that the sellar floor bone was intact using sphenoid sinus computed tomography. All patients underwent an endoscopic transnasal approach, and the authors created a pedicled nasoseptal flap and sellar floor bone flap intraoperatively and reconstructed the skull base at the end of the surgery. Postoperative complications constituted cerebrospinal fluid leakage, brain tissue herniation, nasal discomfort, decreased sense of smell, and epistaxis.

RESULTS

Cerebrospinal fluid leakage occurred in 13 patients (43.3%) intraoperatively; small amounts in 6 patients (20.0%), moderate amounts in 3 patients (10.0%), and large amounts in 4 patients (13.3%). Only 1 patient (3.3%) with large-volume cerebrospinal fluid leakage intraoperatively experienced cerebrospinal fluid leakage postoperatively, and this resolved with lumbar catheter drainage and bed rest. The 6-month postoperative follow-up brain computed tomography findings revealed brain tissue herniation in no patients, nasal discomfort in 3 patients (10.0%), decreased sense of smell in 5 patients (16.7%), and epistaxis in 2 patients (6.7%).

CONCLUSION

Reconstructing the skull base with a sellar floor bone flap and a pedicled nasoseptal flap played an important role in preventing cerebrospinal fluid leakage and brain tissue herniation in endoscopic transnasal pituitary adenoma surgery and did not increase the incidence of postoperative nasal discomfort, decreased sense of smell, or epistaxis.