technical-approach-for-infrared-tracking-for-soft-tissue-navigation

Technical Approach for Infrared Tracking for Soft Tissue Navigation with a Holographic Head-Mounted Display and Preclinical Validation

Augmented Reality (AR) has the potential to enhance surgical guidance by superimposing three-dimensional (3D) anatomical information directly onto the ...

Princess Máxima Center for Pediatric Oncology

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.

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

Augmented reality-guided localization of a chest wall tumor in a pediatric patient.

Pediatric renal tumors are often heterogeneous lesions with variable regions of distinct histopathology. Direct comparison between in vivo imaging and ex vivo histopathology might be useful for identification of discriminating imaging features.

Direct correlation of MRI with histopathology in pediatric renal tumors through the use of a patient-specific 3-D-printed cutting guide: a feasibility study.

Wilms tumor is a common pediatric solid tumor. To evaluate tumor response to chemotherapy and decide whether nephron-sparing surgery is possible, tumor volume measurements based on magnetic resonance imaging (MRI) are important. Currently, radiological volume measurements are based on measuring tumor dimensions in three directions. Manual segmentation-based volume measurements might be more accurate, but this process is time-consuming and user-dependent. The aim of this study was to investigate whether manual segmentation-based volume measurements are more accurate and to explore whether these segmentations can be automated using deep learning. We included the MRI images of 45 Wilms tumor patients (age 0-18 years). First, we compared radiological tumor volumes with manual segmentation-based tumor volume measurements. Next, we created an automated segmentation method by training a nnU-Net in a five-fold cross-validation. Segmentation quality was validated by comparing the automated segmentation with the manually created ground truth segmentations, using Dice scores and the 95th percentile of the Hausdorff distances (HD95). On average, manual tumor segmentations result in larger tumor volumes. For automated segmentation, the median dice was 0.90. The median HD95 was 7.2 mm. We showed that radiological volume measurements underestimated tumor volume by about 10% when compared to manual segmentation-based volume measurements. Deep learning can potentially be used to replace manual segmentation to benefit from accurate volume measurements without time and observer constraints.

Radiologic versus Segmentation Measurements to Quantify Wilms Tumor Volume on MRI in Pediatric Patients.

Patient-specific 3D models of neuroblastoma and relevant anatomy are useful tools for surgical planning. However, these models do not represent the heterogenous biology of neuroblastoma. This heterogeneity is visualized with the ADC and I-MIGB-SPECT-CT imaging. Combining these multi-modal data into preoperative 3D heatmaps, may allow differentiation of the areas of vital and non-vital tumor tissue. We developed a workflow to create multi-modal preoperative 3D models for neuroblastoma surgery.

Multi-modal 3-Dimensional Visualization of Pediatric Neuroblastoma: Aiding Surgical Planning Beyond Anatomical Information.

Surgical treatment of pediatric chest wall tumors requires accurate surgical planning and tumor localization to achieve radical resections while sparing as much healthy tissue as possible. Augmented Reality (AR) could facilitate surgical decision making by improving anatomical understanding and intraoperative tumor localization. We present our clinical experience with the use of an AR system for intraoperative tumor localization during chest wall resections. Furthermore, we present the pre-clinical results of a new registration method to improve our conventional AR system.

Clinical Application and Further Development of Augmented Reality Guidance for the Surgical Localization of Pediatric Chest Wall Tumors.

The International Society of Paediatric Oncology-Renal Tumour Study Group (SIOP-RTSG) discourages invasive procedures to determine the histology of paediatric renal neoplasms at diagnosis. Therefore, the histological subtype of Wilms' tumours (WT) is unknown at the start of neoadjuvant chemotherapy. MR-DWI shows potential value as a non-invasive biomarker through apparent diffusion coefficients (ADCs). This study aimed to describe MR characteristics and ADC values of paediatric renal tumours to differentiate subtypes.

Direct correlation of MR-DWI and histopathology of Wilms' tumours through a patient-specific 3D-printed cutting guide.

In this retrospective single center cohort study, we report the surgical outcomes of nephron-sparing surgery (NSS) for Wilms' tumor (WT) patients since centralization of pediatric oncology care in the Netherlands, and implementation of technological advancements. Therewith we describe the influence of experience and innovations for this type of surgery.

Nephron-sparing Surgery for Pediatric Renal Tumors After Centralization of Pediatric Oncology Care in the Netherlands: Improved Outcomes With 3D Modeling.

Current pediatric renal tumor treatment protocols allow for nephron-sparing surgery (NSS) for unilateral disease only under strict conditions. Oncological guidelines do not account for surgical feasibility, however, possibly reducing the utilization of NSS. To potentially change this, a definition of surgical feasibility is required. This study aimed to define surgical consensus statements for the assessment of patients with Wilms tumor (WT) for NSS.

Nephron-Sparing Surgery for Patients With Wilms Tumor, a Surgical Delphi Study Consensus Statement.

Wilms' tumor is a common pediatric renal malignancy. In selected cases, nephron-sparing surgery (NSS) may be employed as part of the surgical approach. To prevent positive margins, optimal understanding of the tumor-kidney edge is essential. Augmented reality (AR) enables intraoperative visualization of patient-specific three-dimensional (3D) holograms. In this study, we aim to validate the clinical feasibility of a holographic landmark-based registration system in pediatric patients planned for a total nephrectomy (TN), to ensure that the holographic visualization will not influence surgical decision making. In a single-center prospective study, ten pediatric patients undergoing TN were included. Patient-specific 3D holograms were created from preoperative MRI, and intraoperatively landmark-based registration was performed using the HoloLens 2. Clinical feasibility was conducted using accuracy measurements, the System Usability Scale (SUS), and a self-developed questionnaire. Three out of ten patients had a successful registration with a median measured accuracy of 7.0 mm (Interquartile Range (IQR) 6-13.5) and a median SUS score of 75 (IQR 65-77.5). Surgeons reported improved depth perception and anatomical understanding. However, in seven out of ten patients, registration failed due to multiple reasons. The most important factors were large tumor volumes obstructing landmark placement and insufficient spatial distributions of the landmarks, causing rotational misalignment. Although AR showed potential in improving the depth perception and relation in anatomical structures, the landmark-based registration with the HoloLens 2 was currently deemed insufficient for clinical implementation in pediatric abdominal surgery.

Article	Year
Virtual Resection: A New Tool for Preparing for Nephron-Sparing Surgery in Wilms Tumor Patients. Current oncology (Toronto, Ont.)\| PubMed ID: 35200565	2022
Augmented reality-guided localization of a chest wall tumor in a pediatric patient. European journal of cancer (Oxford, England : 1990)\| PubMed ID: 35598357	2022
Direct correlation of MRI with histopathology in pediatric renal tumors through the use of a patient-specific 3-D-printed cutting guide: a feasibility study. Pediatric radiology\| PubMed ID: 36040524	2023
Radiologic versus Segmentation Measurements to Quantify Wilms Tumor Volume on MRI in Pediatric Patients. Cancers\| PubMed ID: 37046776	2023
Multi-modal 3-Dimensional Visualization of Pediatric Neuroblastoma: Aiding Surgical Planning Beyond Anatomical Information. Journal of pediatric surgery\| PubMed ID: 38461108	2024
Clinical Application and Further Development of Augmented Reality Guidance for the Surgical Localization of Pediatric Chest Wall Tumors. Journal of pediatric surgery\| PubMed ID: 38472040	2024
Direct correlation of MR-DWI and histopathology of Wilms' tumours through a patient-specific 3D-printed cutting guide. European radiology\| PubMed ID: 39115585	2025
Nephron-sparing Surgery for Pediatric Renal Tumors After Centralization of Pediatric Oncology Care in the Netherlands: Improved Outcomes With 3D Modeling. Journal of pediatric surgery\| PubMed ID: 39765026	2025
Nephron-Sparing Surgery for Patients With Wilms Tumor, a Surgical Delphi Study Consensus Statement. Pediatric blood & cancer\| PubMed ID: 40059283	2025
Introducing Holographic Surgical Navigation in Pediatric Wilms' Tumor Patients: A Feasibility Study During Total Nephrectomy. Bioengineering (Basel, Switzerland)\| PubMed ID: 40868409	2025

Matthijs Fitski

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