Virtual Resection: A New Tool for Preparing for Nephron-Sparing Surgery in Wilms Tumor Patients

Abstract

Nephron-sparing surgery (NSS) in Wilms tumor (WT) patients is a surgically challenging procedure used in highly selective cases only. Virtual resections can be used for preoperative planning of NSS to estimate the remnant renal volume (RRV) and to virtually mimic radical tumor resection. In this single-center evaluation study, virtual resection for NSS planning and the user experience were evaluated. Virtual resection was performed in nine WT patient cases by two pediatric surgeons and one pediatric urologist. Pre- and postoperative MRI scans were used for 3D visualization. The virtual RRV was acquired after performing virtual resection and a questionnaire was used to assess the ease of use. The actual RRV was derived from the postoperative 3D visualization and compared with the derived virtual RRV. Virtual resection resulted in virtual RRVs that matched nearly perfectly with the actual RRVs. According to the questionnaire, virtual resection appeared to be straightforward and was not considered to be difficult. This study demonstrated the potential of virtual resection as a new planning tool to estimate the RRV after NSS in WT patients. Future research should further evaluate the clinical relevance of virtual resection by relating it to surgical outcome.

Preoperative three-dimensional modelling and virtual reality planning aids nephron sparing surgery in a child with bilateral Wilms tumour

“…Some differences between the virtual planning and the actual resection performed have been reported 12. In our case, visualisation of the left kidney on CECT was poor due to reduced GFR but immersive VR enabled overlay of 2D scan on the 3D model and allowed virtual resection of the tumour using immersive tools.…”

“…Several authors have reported that correlating renal function and RRV may help in estimating postoperative outcomes than RRV alone 12 22. Studies have shown that patients in their fifth decade who underwent unilateral nephrectomy in childhood due to Wilm’s tumour have significantly less eGFR as expected for the physiological renal function decline with age (p=0.001) 23 24.…”

“…While volume rendering of these images provides a perspective, virtual reality (VR) reconstruction allows an immersive view of the vascular anatomy and the feeding vessels. Preoperative virtual resection provides a precise visual aid to the operating surgeon that can be replicated during NSS 12 13. Based on the Digital Imaging and Communications in Medicine (DICOM) data of CT or MRI scans and relevant patient information, a 3D environment can be designed that, once fed into a special software, can generate VR models.…”

Technical advances in the surgical management of Wilms tumors in children

“…be achieved, and the relationship of the resection margin with essential anatomical structures can be studied. 26 With these applications of 3D techniques, surgeons may be able to prepare more thoroughly for surgery.…”

“…In addition, these 3D holograms can be used as a basis for virtual resection, that is, digitally practicing NSS. With virtual resection, the remaining kidney volume can be calculated in order to determine whether NSS is worthwhile, if the resection can be achieved, and the relationship of the resection margin with essential anatomical structures can be studied 26 . With these applications of 3D techniques, surgeons may be able to prepare more thoroughly for surgery.…”