gms | German Medical Science

Objective: Endoscopic technique improves to the gold standard in modern transsphenoidal surgery. However, endoscopy is not in routine use everywhere. Neurosurgeons are often cautious because the unfamiliar endonasal anatomy and unusual para-endoscopic dissection. In addition permanent contamination of the endoscope with blood and nasal secretions hinders orientation, requiring a steep learning curve.

Methods: This publication presents first authors learning curve in endoscopic transsphenoidal surgery of pituitary adenomas. During this period, rhinosurgical co-operation was not available. The initial 100 consecutive cases were retrospectively analyzed reviewing office charts, medical reports, radiographs and videotapes. Two cohorts were compared: the initial cases 1–25 and the cases 76–100 according to the criteria: 1) changing to microsurgical technique; 2) duration of surgery; 3) surgical complications.

Results: In the initial 25 cases, the endoscopic technique was abandoned in 6 cases, in the last 25 cases surgical microscope was not more used. The average duration of surgery was in the initial cases 2:25h (1:05–4:00), compared with 1:05h (0:38–2:15) in the last 25 cases. Surgical complications were as following: nasal re-bleeding 2 versus 0; hyposmia 4 vs. 1; intraoperative CSF leak 8 vs. 3; postoperative CSF fistula 3 vs. 1; permanent diabetes insipidus 1 vs. 0.

Conclusions: Endoscopic technique in transsphenoidal surgery requires significant learning curve, thus also resulting in approach related complications. In our experience, two circumstances may facilitate the initial effort: 1) use of high sophisticated endoscopic equipment; 2) significant training on cadavers. However, as later experience showed, a fruitful co-operation with rhinological surgeons seems to be the most important factor in shortening neurosurgical learning curve in transsphenoidal endoscopic surgery.