Minimally-invasive tubular retraction ports for intracranial neurosurgery: History and future perspectives

Brain retraction is a necessary yet potentially damaging requirement of accessing lesions located in deep structures. The development of minimally-invasive tubular retractors (MITRs) provides the theoretical advantage of maximizing visualization of and access to deep-seated lesions, all while minimizing collateral tissue damage. These advantages make MITRs preferable to traditional bladed retractors in the majority of deep-seated lesions. Several commercially-available MITR systems currently exist and have been shown to aid in achieving excellent outcomes with acceptable safety profiles. Nevertheless, important drawbacks to currently-available MITR systems exist. Continued pursuit of an ideal MITR system that provides maximal visualization and access to deep-seated lesions while minimizing retraction-related tissue damage is therefore important. In this review, we discuss the historical development of MITRs, the advantages of MITRs compared to traditional bladed retractors, and opportunities to improve the development of prospective MITRs.