Mixed-reality head-mounted display in cranial neurosurgery: A proof-of-concept study

Mixed-reality (MR) head-mounted displays (HMD) offer virtual augmentations registered with real objects, allowing for direct patient-centered lesion visualization. In contrast to other surgical subspecialties, however, the application of MR in neurosurgery remains poor. In this proof-of-concept study, we aimed at evaluating the applicability, educational value, and accuracy of HMD as compared to standard neuronavigation (SN) in the planning of treatment for patients undergoing neurovascular and tumor surgeries.

A 3D hologram of the patient’s anatomy was generated from conventional CT scan, MRI, and/or 3D rotational angiography (3D-RA), and integrated into the HMD. The participating surgeons completed a standardized questionnaire, which evaluated the application of HMD compared to SN, to detail the visualization benefits and limitations of the 3D hologram.

Eight consecutive patients with neurovascular (n = 4) or tumor pathologies (n = 4) were selected for MR. The mean (±SD) setup time was significantly longer for HMD than SN (8.3 ± 1.5 min vs. 4.8 ± 1.3 min; p < 0.001), independent of the pathology applied (i.e., tumor: 8.0 ± 2.0 vs. 4.3 ± 1.3, p = 0.02, and vascular: 8.7 ± 0.9 vs. 5.4 ± 1.1; p < 0.001). Surgeons wearing the HMD succeeded in moving the 3D hologram from respective operators’ angles and identifying the shape and configuration of the lesion. The MR device was superior to SN with regard to treatment planning on account of its improved spatial awareness. The current method is however limited in its representation of small perforators in neurovascular pathologies and bony involvement in tumors.

MR may become a valuable tool in the preoperative treatment planning, education and guidance of complex procedures in selected patients, yet further development is necessary to improve the clinical applicability of the MR HMD.