Light at the end of the tunnel: the learning curve associated with endoscopic transsphenoidal skull base surgery

Endoscopic transsphenoidal resection of skull base lesions has been introduced widely as an alternative to microscopic transmucosal approaches. We report the introduction of this technique to our unit, including the learning curve recognized for this procedure, comparing techniques in a concurrent case-control fashion. All patients operated on for sellar, suprasellar, or clival lesions were considered for endoscopic surgery, with 51 patients undergoing endoscopic surgery and 46 having microscopic surgery with the operating method determined by the availability of the ear, nose, and throat surgeon involved with the procedures. Endoscopic surgery compared favorably with microscopic surgery with respect to endocrine control, length of stay, diabetes insipidus, and cerebrospinal fluid leakage. A learning curve was found with a significant fall in complication rates between the first third and most recent third of the cohort. Endoscopic skull base surgery has superior results to microscopic approaches once the initial learning curve is overcome, but this can be done quickly and safely.