Comparison of patient-centric factors in minimally invasive transcranial versus classic approaches: a matched cohort study.

Objective: The principal tenet of minimally invasive neurosurgery is to limit approach-related tissue trauma, and a major assumption is that shorter incisions and smaller openings, in addition to protecting the brain, also have some perceptible benefits for the patient. This study tests the assumption of patient benefit and tries to define its significance.

Methods: Procedures that fit the inclusion criteria of minimally invasive transcranial "keyhole" surgery were sought in the principal investigator's archives. Each case was then paired with a classic procedure performed within the study time frame by the two senior authors, matched for pathology, size, location, and complexity. These pairs were then compared using a statistical tool (i.e., the Wilcoxon signed-rank test) designed for matched samples. Differences in estimated blood loss, duration of surgery, and length of hospital stay were examined. The narcotic needs during hospitalization were also examined as morphine milligram equivalent (MME).

Results: Ninety patients were included in this study, evenly split between the minimally invasive surgery (MIS) and classic cohorts. Comparison of the 45 pairs showed no significant difference in estimated blood loss, though the operative times favored the MIS cohort significantly (mean ± SEM 310 ± 17 minutes vs 383 ± 24 minutes, p = 0.02). The length of stay was shorter for MIS, but the difference reached statistical significance only when cases with complications were excluded. The most important finding was that significantly less narcotic was needed during hospitalization in the MIS cohort (83 ± 15 MME vs 257 ± 47 MME).

Conclusions: The large difference in narcotic needs points to enhanced recovery from MIS techniques. While the difference in operative time did not lead to significantly shorter hospital stays, data suggest that minimally invasive technique may benefit the patient during recovery. This inspires further investigations to define the potentially positive impact on hospital and healthcare systems.