Introduction: Improvement in intraoperative and postoperative parameters for 3 experienced neurosurgeons was analysed, as they shift from microscopic to endoscopic approach for pituitary adenoma.
Methods: Retrospective analysis of 110 consecutive patients who underwent endoscopic endonasal binostril transsphenoidal surgery for pituitary adenomas was done. Patients were evaluated for preoperative symptoms, tumor size, hormonal deficits and visual status. Intraoperative CSF leak, blood loss, operative time, sinus/ICA injury and conversion to microscopic technique were evaluated. Postoperative visual status, hormonal imbalance, electrolyte imbalance, meningitis were evaluated along with percentage of tumor excision. All cases were divided into two halves and each surgeon’s(n=3) early results were compared with later results to look for learning curve. Learning trend of 3 surgeons was individually studied and analysed.
Results: 110 cases were operated by 3 surgeons; each with experience of at least 7 years and operated >100 pituitary cases microscopically. Comparing first 55 cases operated with second half, mean postoperative stay decreased from 8.67 to 5.5 days(p=0.002). Operative time decreased from 145 minutes to 135 minutes. There was significant improvement gross total resection with 16 in first half and 37 in second half(p=0.000). Despite mean preoperative tumor size being marginally larger in the second half(6.59v/s6.38cc) than the first half, mean postoperative size of residual tumor reduced from 1.32cc to 0.72cc(p=0.085). Most significant difference was improvement in extent of resection(85.03%-first half v/s 92.41%-second half(p=0.008)). Visual improvement was seen in 6 patients in first group, and 10 patients in second group(p=0.279). 3 patients had postoperative meningitis and 1 had deterioration in mental status in first half while there were no such complications in second half.
Conclusions: Endoscopic transsphenoidal approach for pituitary adenomas is novel technique and requires technical expertise. Our results demonstrate that there is definite learning curve to master its subtle nuances, but with time and experience, postoperative results show marked improvement.
Patient Care: The study suggests that shifting from microscopic to endoscopic approach for pituitary adenomas for an experienced neurosurgeon involves a steep learning curve; but results in reduction in mean postoperative stay and complications, and improvement in gross total resection, extent of resection and visual improvement.
Learning Objectives: 1. Endoscopic transsphenoidal approach for pituitary adenomas requires technical expertise; there is definite learning curve to master its subtle nuances.
2.Trends during learning curve of shift from microscopic to endoscopic approach for pituitary adenoma:
a. reduction in mean postoperative stay,
b. improvement gross total resection,
c. improvement in extent of resection,
d. improvement in visual improvement,
e. reduction in complications.