Early-Career Surgical Practice for Cerebellopontine Angle Tumors in the Era of Radiosurgery

Abstract

We analyzed the outcomes of patients with large cerebellopontine angle (CPA) tumors treated by a skull-base team in which two surgeons (one neurosurgeon and one otological surgeon) were in the beginning of their careers (<40 years old). Data of patients operated on between April 2012 and March 2016 were reviewed. All factors related to surgical training were considered. Thirty-one patients had vestibular schwannomas, while 26 had meningiomas. Mean tumor diameter was 30.6 mm (range, 23–49 mm) for schwannomas and 35 mm (range, 22–51 mm) for meningiomas. Satisfactory postoperative facial nerve function (House–Brackmann's grade I or II) was achieved in 20 (64.5%) schwannoma patients and 21 (80.7%) meningioma patients. Gross total and near-total resections (residual tumor < 5 mm) were achieved in 21 (67.7%) and 9 (29%) schwannoma patients, respectively. Gross total resection (Simpson's grade II) was achieved in 18 (69.2%) meningioma patients. In both groups, the retrosigmoid approach was the most common approach. Regarding surgical training of the two younger surgeons, during the residency period, they attended high-volume centers for CPA tumors. Application of microsurgical techniques was systematically applied from the beginning of their personal series in every intracranial pathology case. During the first 2 years of the series, they were supervised by more experienced surgeons and followed a stepwise sharing of increasingly difficult surgical phases; by comparing results of this period with the last 2 years of the series, where they acquired a complete autonomy, no relevant difference was detected. Our results suggest that young surgeons may achieve good results even at the beginning of their careers, if specific conditions related to training and mentorship are met.

Keywords

cerebellopontine angle tumor - retrosigmoid - skull base - translabyrinthine - vestibular schwannoma

Notes

1. Radiosurgery for small-to-medium size schwannomas and meningiomas of the CPA have raised questions regarding the training of new skull-base surgeons.

2. The learning curve for this surgery is steep and requires early interest and dedication by the residents and younger surgeons.

3. Satisfactory results can be achieved in the hands of younger skull-base surgeons if these are specifically trained.

4. Trainees interested in this type of surgery should attend high-volume centers for CPA tumor cases and learn the entire management path.

5. They should take advantage of anatomy laboratories and modern three-dimensional neuroimaging modeling and simulation which also allow for visualization of various surgical approaches.

6. Manual dexterity should be progressively enhanced through the application of microsurgical techniques for vascular and neural manipulation and the constant use of surgical microscopes and microinstruments in every single tumor case, starting from superficially seated pathologies and progressing to deeper, more complex tumors.

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