Background:
Maximal safe resection in Glioblastoma multiforme (GBM) surgery is the primary goal. Complete resection of contrast-enhancing tumor has been recognized as an important prognostic factor. Different intraoperative technologies and image modalities have been used to improve GBM surgery over the years including florescence guided surgery with 5-ALA and augmented reality.
Objective:
No study to date has evaluated the extent of resection using augmented reality (AR) in microsurgical resection of GBM. The Neurosurgery department of Geneva developed a procedure using AR displayed directly into the microscopes oculars to enhance the surgery. Our objective for this pilot study was to review our first patients operated with this AR system and compare our rates of extent of resection and new neurological deficits with the literature using 5-ALA fluorescent guided surgery.
Methods:
A retrospective analysis of the surgical parameters of 18 patients operated in the University Hospital of Geneva for a GBM was conducted. All patients beneficiated from a microsurgical resection of a GBM with the help of an AR system from 19th February 2015 to the 28th October 2020. We measured the preoperative and postoperative GBM volumes to describe the extent of resection that was achieved. Patients characteristics and surgery parameters were described. Literature on the extent of resection using the gold-standard procedure 5-ALA was reviewed and extent of resection rates and new neurological deficits were compared. Pubmed/Embase were searched for studies evaluating the extent of resection in 5 ALA-surgery.
Results:
Post-operative volumes were median 0.0 cm3 [range 0.0 – 3.78]. Gross total resection was achieved in most cases: 13/18 [72.2%]. There was no difference between the GTR rate in our patients and literature (72.2% vs 73,7%, P= 1,00). The difference in new postoperative neurological deficits did not achieve statistical significance (16% vs 25%, P = 0.5845). Eloquent surgery rate was significatively different, with more eloquent surgeries in the literature (33% vs 56%, P=0,088).
Conclusions:
Our study was too underpowered to draw significant conclusion on the difference of extent of resection between AR surgery and 5-ALA surgery. Literature was found to be too heterogenous to have a valid comparison. A case-control study with randomization of AR usage and a blinded analysis from a central comity is recommended.