Endoscopic versus Microscopic Transsphenoidal Resection of Sellar Pathologies: New and Learning Against the Advanced Expert

Introduction: Endoscopic neurosurgery is emerging for transsphenoidal resection of sellar lesions. From a technical point of view endoscopic (E) resections should be better than microscopic (M) resections due to improved visibility.

Methods: Data were collected retrospectively of patients operated for a sellar lesion in our institution between November 2004 and August 2012. Statistics were conducted by Fisher's exact and student's t-tests.

Results: In total 117 patients were operated (E: n = 52, M: n = 65; +/− 10–19 cases/yr). Age and gender distribution did not differ between groups (mean = 54yrs, 67% male). Mean follow up was 36 months (range 0–95). Most frequent pathology was hormone inactive adenoma (60% E, 51% M). E-group consisted of more invasive, larger lesions: giant lesions (19% E versus 8% M), Knosp grade IV (19 E versus 8% M). Neuronavigation was used in 80% of E-cases, but never in M-cases. OR duration was stable in the experienced M-group (+/− 94 minute). The E-group showed a learning curve in mean OR-time (2004–2007: 154 minute, 2008–2012: 93 minute). Intraoperative CSF leaks were seen in 31% (E) versus 42% (M) of cases. More E-cases were reoperated and more M-cases received a lumbar drainage (5 versus 1, 8 versus 19 patients resp.). In both groups 2 patients were reoperated because of a large residual tumor. ICA was damaged in 1 E-case with mild residual symptoms. Postoperative diabetes insipidus occurred more often after an E-operation (17 versus 5%, p = 0.03). Postoperative anterior pituitary dysfunction rate in formerly intact patients was higher in the micro group (25% versus 19%). Improved visual outcome was shown in 46% (E, longer visual preoperative deficits than M) versus 61% (M) of patients. Clinical performance improved in 38% (E, less hormonal preoperative deficits than M) versus 78% (M) of patients. Total resection was better in microscopic patients (48% versus 42%), whereas after endoscopic operations a small residuum (<10mm) was seen more often (38% versus 29%). A large residuum (>10mm) was seen in 20% (E) versus 23% (M) of patients.

Conclusions: In the past 8 years endoscopic technique was not better, yet not worse either. Considering the small sample size and the comparison of a learning endoscopic neurosurgeon and a very experienced microscopic one better results are to be expected in the future with refinements of operative techniques.