Abstract
Objective The aim of this study was to evaluate the rate of complications and the extent of
resection (EOR) of nonfunctioning pituitary adenomas by endoscopic endonasal approach
(EEA) in a 15-year learning curve.
Methods A total of 100 patients operated by the same surgical team were divided chronologically
into two, three, and four groups, comparing differences in EOR measured by a semiautomatic
software (Smartbrush, Brainlab), rate of immediate postoperative complications, and
the visual and hormonal status at 6 months.
Results There were no significant differences over the years in rates of postoperative complications
and in visual status at 6 months. A significant linear correlation between the EOR
and the number of surgeries (rho = 0.259, p = 0.007) was found. The analysis was performed in three groups because of the remarkable
differences among them; the EOR were: 87.2% (early group), 93.03% (intermediate group),
and 95.1% (late group) (p = 0.019). Gross total resection was achieved in 30.3, 51.5, and 64%, respectively
(p = 0.017); also, the rate of reoperation and the worsening of at least one new hormonal
axis were worse in the early group. Consequently, the early group had a higher risk
of incomplete resection compared with the late group (odds ratio: 4.2; 95% confidence
interval: 1.5–11.7). The three groups were not different in demographic and volume
tumor variables preoperatively.
Conclusions The first 33 interventions were associated with a lower EOR, a high volume of residual
tumor, a high reoperation rate, and a higher rate of hormonal dysfunction. We did
not find differences in terms of postoperative complications and the visual status
at 6-month follow-up.
Keywords nonfunctioning pituitary adenoma - learning curve - extent of resection - gross total
resection - semiautomatic volumetry - transsphenoidal approach - endoscopic endonasal
approach
