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OBJECTIVE Different techniques of performing image-guided neurosurgery exist, namely, neuronavigation systems, intraoperative ultrasound, and intraoperative MRI, each with its limitations. Except for ultrasound, other methods are expensive. Three-dimensional virtual reconstruction and surgical simulation using 3D volume rendering (VR) is an economical and excellent technique for preoperative surgical planning and image-guided neurosurgery. In this article, the authors discuss several nuances of the 3D VR technique that have not yet been described. METHODS The authors included 6 patients with supratentorial gliomas who underwent surgery between January 2019 and March 2021. Preoperative clinical data, including patient demographics, preoperative planning details (done using the VR technique), and intraoperative details, including relevant photos and videos, were collected. RadiAnt software was used for generating virtual 3D images using the VR technique on a computer running Microsoft Windows. RESULTS The 3D VR technique assists in glioma surgery with a preoperative simulation of the skin incision and craniotomy, virtual cortical surface marking and navigation for deep-seated gliomas, preoperative visualization of morbid cortical surface and venous anatomy in surfacing gliomas, identifying the intervenous surgical corridor in both surfacing and deep-seated gliomas, and pre- and postoperative virtual 3D images highlighting the exact spatial geometric residual tumor location and extent of resection for low-grade gliomas (LGGs). CONCLUSIONS Image-guided neurosurgery with the 3D VR technique using RadiAnt software is an economical, easy-to-learn, and user-friendly method of simulating glioma surgery, especially in resource-constrained countries where expensive neuronavigation systems are not readily available. Apart from cortical sulci/gyri anatomy, FLAIR sequences are ideal for the 3D visualization of nonenhancing diffuse LGGs using the VR technique. In addition to cortical vessels (especially veins), contrast MRI sequences are perfect for the 3D visualization of contrast-enhancing high-grade gliomas.

Polypropylene is stiffer than polyethylene, having high heat distortion temperature. It is autoclaveable, offers excellent chemical resistance, environment stress-cracking resistance and surface hardness. It is not possible to produce rotomolded article from injection moulding polypropylene grade because melt flow index (MFI) required for polypropylene rotomoulding is higher. Also, injection moulding grade PP is not suitable to prevent the material from thermo oxidative degradation during long rotomoulding cycles. The reactive extrusion is a promising technique to get higher MFI, which can be used for rotomoulding process with proper additive package. In this paper the polypropylene grade is modified for rotational moulding applications with the help of reactive extrusion. It is done in order to get higher MFI polypropylene. Sintering is observed to be related to zero shear viscosity and directly to MFI. During the experimentation it was observed that, for higher MFI material sintering completed at lower temperature. It is found that as MFI increases the flexural properties of rotomoulded specimen increases, and notched izod impact, tensile strength, and elongation at break decreases. Fine spherulites were observed for low viscosity material. SEM images revealed the coarseness with increased MFI.