3D perfusion mapping and virtual surgical planning in the treatment of pediatric embryonal abdominal tumors

Introduction: 3D imaging and surgical planning for the treatment of embryonal tumors using different techniques (CT versus MRI) are presently under discussion. Up to now, the main focus has been on visualizing the anatomy. Contrast medium dynamics have not been taken into consideration. The aim of the present study was to establish the technical means of integrating the 3D images from functional MRI data into the anatomical images and to determine clinical applications for this approach. Material and Methods: In 11 patients (mean age: 2.4 years) with solid tumors, 26 diagnostic MRI examinations were performed for primary diagnosis, treatment monitoring, or as part of the surgical planning. Seven children presented with neuroblastomas, three with Wilms' tumor, and one with advanced bilateral nephroblastomatosis. The MRI data were acquired using a 1.5-T system. For post-processing, we used volume rendering software, including an evaluation of perfusion. By using color-coded parametric images and integrating functional information, perfusion could be visualized and used for interactive surgical planning. Macroscopic and microscopic sections served as the gold standard for assessing tissue viability. Results: We were able to integrate the dynamic data into the anatomical images for all patients. A good agreement was found between the results of surgical planning, including perfusion mapping, with the surgical site, subsequently produced macroscopic sections and the results of random microscopic examinations. Conclusions: Perfusion mapping using color-coded parametric images of pediatric abdominal tumors extends the diagnostic techniques currently available. We provide first proof of the possibility of integrating functional information into 3D MR images in children. Monitoring the treatment of nephroblastoma and surgical planning for pediatric embryonal tumors represent potential applications of this technique.