The learning curve in minimally invasive pituitary surgery.

Background: Minimally invasive pituitary surgery (MIPS) is performed via an endoscopic transnasal transsphenoidal approach. This provides excellent illumination, visualization, and magnification of the operative field, in addition to avoiding complications associated with other approaches. In this study we examined the first 45 cases of MIPS to determine if a learning curve exists for this technique.

Methods: A retrospective chart review was performed of the first 45 cases of MIPS at a major academic medical center. Cases were divided into three groups of 15 patients each. Group characteristics including age, sex, and revision surgery were compared. Complication rates investigated included death, intracerebral hemorrhage, intraoperative cerebrospinal fluid leak, postoperative cerebrospinal fluid leak, use of lumbar drain, meningitis, postoperative epistaxis, ophthalmoplegia, visual impairment, and diabetes insipidus. Other factors examined included intraoperative blood loss, length of stay, and tumor histology. One way analysis of variance statistical analysis was used to determine the significance of differences between groups.

Results: Groups were comparable in respect to characteristics studied. Statistically significant (p < 0.05) differences in complication rates and other factors between groups were not shown. Complication rates are low.

Conclusion: This study does not establish a learning curve for our first 45 cases of MIPS. This finding supports the concept that an otolaryngology/neurosurgery team skilled in endoscopic techniques and pituitary surgery can safely transition from open approaches to an endoscopic approach in pituitary surgery.