Training in Skull Base Endonasal Endoscopic Surgery: Development and Validation of a Novel Low-Cost Simulation with Animal Cadaveric Model.

BACKGROUND: Endoscopic skull base surgery is constantly evolving and its scope has expanded. The acquisition of surgical skills involves a long learning curve with significant risks for the patient. Therefore, training in the laboratory has become essential to achieve appropriate proficiency and reduce the morbidity and mortality associated with these procedures. The objective of our work is to develop and validate a cost-effective and easily replicable simulator for endonasal endoscopy training using a swine cadaveric model. METHODS: We used fresh Pietrain swine heads. Training exercises of increasing complexity were performed. A Specific Technical Skills and Knowledge Scale was created considering the objectives to be assessed in each task. After the simulation, the trainees were required to answer a satisfaction survey. RESULTS: Ten participants were recruited (5 neurosurgery residents and 5 neurosurgeons). The simulator assessment showed statistically significant differences between groups. Performance was better among the group with endoscopic surgery experience. Face validity was assessed through a postsimulation questionnaire showing an overall mean score of 28.7 out of 30, indicating a highly positive overall assessment of the simulator. Furthermore, 100% of the trainees believe that including endoscopy training in their education would be beneficial. CONCLUSIONS: The endonasal endoscopy training simulator using a swine cadaveric model is a useful and accessible tool for enhancing surgical skills in this field. It provides an opportunity for training outside the operating room, reducing the potential risks associated with patient practice, and improving the training of residents.

Middle turbinate mucosal flap: Low-morbidity option in the management of skull base defects.

BACKGROUND: To describe the low morbidity of middle turbinate mucosal flap (MTMF) to repair anterior skull base defects. METHODS: Skull base endonasal endoscopic surgeries performed at a tertiary hospital between 2015 and 2018 were analyzed. Patients were divided into two groups according the existence or not of a significant intraoperative cerebrospinal fluid (CSF) leak. In Group 1 (n = 28), gasket seal and a pedicled endonasal flap were used to repair the defect: 13 nasoseptal flaps (NSF), 8 inferolateral wall flaps (ILF), and 7 MTMF. In Group 2 only an endonasal flap was used: 9 NSF, 4 ILF, and 18 MTMF. Surgical and recovery time were analyzed (Student's t test). Our favorite surgical technique is described. RESULTS: Fifty-nine patients were included. Average surgical time was 27.7, 41.6, and 11.3 min for NSF, ILF, and MTMF, respectively. MTMF showed a faster recovery. CONCLUSION: MTMF is a safe reconstructive option for anterior skull base defects.

Periodic olfactory assessment in patients undergoing skull base surgery with preservation of the olfactory strip.

OBJECTIVES/HYPOTHESIS: Others have reported olfactory disturbances following endoscopic approaches to the skull base. However, there is a lack of consensus on the extent and duration of dysfunction. This study aimed to compare our results with previously published work and to validate the olfactory strip-sparing approach. STUDY DESIGN: Prospective study to assess olfaction in 50 patients scheduled to undergo resection of skull base tumors via extended endoscopic approaches. METHODS: Patients were divided into two groups. Group I had a nasoseptal flap (NSF), and group II included patients in whom rescue flaps were performed bilaterally. Olfactory outcomes were assessed using repeated University of Pennsylvania Smell Identification Test at baseline, 6 weeks, 3 months, and 6 months following surgery. RESULTS: Ultimately, 42 patients (seven group I and 35 group II) were available for assessment. Scores for group I were lower than at baseline at 6 weeks postoperatively (30.71 ± 5.5 vs. 24.5 ± 5.4; P = .05). However, by the third postoperative month the scores had improved to a level that was not significantly different from baseline (29.0 ± 3.7; P = .5). At 6 months, the score was 30.0 ± 3.9. Patients in group II showed no difference between their baseline and 6-week scores (31.5 ± 5.3 vs. 29.7 ± 5.9; P = .16). Six months postoperatively, the score was significantly higher (33.78 ± 3.6; P = .04). CONCLUSIONS: Expanded endoscopic approaches to skull base tumors involving reconstruction with an NSF are associated with a short-term negative impact on olfaction. Olfaction does not seem to be affected by the surgical resection of pituitary adenomas associated with rescue flaps. Identification of the olfactory epithelium and meticulous harvesting of the NSF are critical to preserve olfaction. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:1970-1975, 2017.

Cirugía hipofisiaria endoscópica transesfenoidal, con realización de colgajo nasoseptal: evaluación del impacto de la técnica en la olfación:. serie de casos / Endoscopic pitituary surgery transsphenoidal, with nasoseptal flap: assessment of the impact of the technique in the olfaction: cases series

Introducción: La cirugía endoscópica transesfenoidal en la exéresis de patología hipofisaria ha sido ratificada dentro de la mejores opciones para conseguir abordajes exitosos. Para cerrar la brecha ósea, se puede utilizar el colgajo nasoseptal, el cual lograría un cierre adecuado y seguro, evitando complicaciones como persistencia de fístulas de líquido cefalorraquídeo. Dentro de los probables efectos secundarios de este colgajo se señala la presencia de anosmia o hiposmia. Objetivo: Nuestro objetivo es mostrar los resultados obtenidos empleando la técnica del colgajo nasoseptal y la evaluación del olfato posoperatorio. Material y método: Incluimos 14 pacientes con diagnóstico de adenoma hipofisiario intervenidos en nuestro servicio entre diciembre 2014 a diciembre 2015. Se evaluaron diversos parámetros entre otros, olfatometría pre y posoperatorias. A todos se les realizó la técnica endoscópica transesfenoidal. Efectuando la disección del colgajo con la técnica tipo Hadad. La exéresis tumoral fue realizada por neurocirujano, se cubrió la osteotomía con este colgajo. Resultados: De los 14 pacientes, 13 llegaron al estado olfativo preoperatorio. 1 paciente se mantuvo hipósmico mantenidamente. En nuestro estudio, no hemos encontrado deterioro significativo en la calidad del sentido del olfato. Así como tampoco observamos otras complicaciones. Conclusiones: Esta experiencia aún inicial, estimamos que podría ya esbozar una tendencia de mantención de la función olfativa en este tipo de cirugía.

Introduction: Transsphenoidal endoscopic surgery resection of pituitary pathology has been ratified within the best options for successful approaches. To close the gap bone, you can use the nasoseptal flap, which achieved an adequate and secure closure, preventing complications such as persistent cerebrospinal fluid leaks. Among possible side effects of this flap anosmia-hyposmia noted. Aim: Our goal is to show the results obtained using the technique of nasoseptal flap and postoperative evaluation of smell. Material and method: We included 14 patients with a diagnosis of pituitary adenoma surgery in our department between December 2014 to December 2015. Various parameters were evaluated pre and post operative, specially olfactory function. All underwent transsphenoidal endoscopic technique. Performing dissection flap with the technical type Hadad. The tumor resection was performed by neurosurgeon, osteotomy covered with this flap. Results: Of the 14 patients, 13 reached the olfactory preoperative state. 1 patient remained with hyposmia. In our study, we found no significant deterioration in the quality of the sense of smell. Not other complications were found. Conclusions: This is an initial experience, and we estimate that could outline a trend of maintaining olfactory function in this surgery approach.

Assessment of mucocele formation after endoscopic nasoseptal flap reconstruction of skull base defects.

Advances in endoscopic skull base (SB) surgery have led to the resection of increasingly larger cranial base lesions, resulting in large SB defects. These defects have initially led to increased postoperative cerebrospinal fluid (CSF) leaks. The development of the vascularized pedicled nasoseptal flap (PNSF) has successfully reduced postoperative CSF leaks. Mucocele formation, however, has been reported as a complication of this technique. In this study, we analyze the incidence of mucocele formation after repair of SB defects using a PNSF. A retrospective review was performed from December 2008 to December 2011 to identify patients who underwent PNSF reconstruction for large ventral SB defects. Demographic data, defect site, incidence of postoperative CSF leaks, and rate of mucocele formation were collected. Seventy patients undergoing PNSF repair of SB defects were identified. No postoperative mucocele formation was noted at an average radiological follow-up of 11.7 months (range, 3-36.9 months) and clinical follow-up of 13.8 months (range, 3-38.9 months), making the overall mucocele rate 0%. The postoperative CSF leak rate was 2.9%. Proper closure of SB defects is crucial to prevent CSF leaks. The PNSF is an efficient technique for these repairs. Although this flap may carry an inherent risk of mucocele formation when placed over mucosalized bone during repair, we found that meticulous and strategic removal of mucosa from the site of flap placement resulted in a 0% incidence of postoperative mucocele formation in our cohort.