Tailored Craniotomy and Perilesional Dissection for Brain Tumor Removal

A tailored craniotomy with the aid of neuronavigation is performed. After durotomy and exposure of the brain, a corticectomy around the most superficial part of the tumor is performed. A sort of perilesional plane around the contrast-enhancing part of the tumor is found through the tractionof the tumor away from the normal appearing brain using dedicated spatulas (see Fig. 1).Fig. 1

Shows the identification of a perilesional plane through traction with dedicated dissection spatulas. A and B show a case of a left parietal GB

In this way, the white matter is gradually and circumferentially suctioned until the bottom of the tumor is reached. This circumferential movement allows the surgeon to perform the hemostasis during the surgical resection progressively;it also delineates a separation plane in the white matter (or at the level of the arachnoid sulci when they form a part of the dissection planes) that can be protected placing a cottonoid pattie over another in a “shingles on the roof” fashion while the circumferential dissection is progressing. The use of neuronavigation and intraoperative ultrasound (iOUS) reduces the risk of losing a correct trajectory around the tumor; in this way, this is circumnavigated (see Fig. 2).Fig. 2

Shows the circumnavigation of a case of a right fronto-opercular GB: AT2-weighted preoperative MRI; B,C T1-weighted with gadolinium pre-operative brain MRI. D–F A dissection plane is found and delimited with cottonoid patties

After the bottom is reached, a cottonoid pattie is placed over the normal appearing white matter. When the tumor has been circumnavigated, it can be detached from the bottom of the surgical cavity and removed enbloc with a film of normal-appearing white matter attached to the contrast-enhancing tumor. When the volume of the tumor mass does not allow the surgeon to spatulate the white matter, it can be centrally debulked, like in meningioma surgery, to permit tractions (see Supplemental Fig. 1). Hemostasis is easily performed with gentle retraction of the patties and coagulating the strips of white matter attached to them. An online intraoperative video is available in the supplementary materials. After resection is considered completed by the primary surgeon and checked with an iOUS, biopsy samples are randomly collected with dedicated forceps from the walls of the surgical cavity that are not considered in relation to eloquent areas (see Fig. 3). No surgical adjuncts are used in order to avoid false negative results.Fig. 3

This figure shows a case of a right temporal GB operated with the perilesional dissection technique. In this picture it is possible to understand how US and MRI can look like similar pictures