Subject-specific modelling of pneumoperitoneum: model implementation, validation and human feasibility assessment

• Published in: International journal for computer assisted radiology and surgery Vol. 14; no. 5; pp. 841 - 850
• Main Authors: Camara, Mafalda, Dawda, Shivali, Mayer, Erik, Darzi, Ara, Pratt, Philip
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.05.2019; Springer Nature B.V
• Subjects: Abdomen; Biomechanics; Computer Imaging; Computer Science; Computer simulation; Feasibility studies; Health Informatics; Imaging; Mathematical models; Medicine; Medicine & Public Health; Metric space; Modelling; Original; Original Article; Parameter estimation; Pattern Recognition and Graphics; Radiology; Real time; Surgery; Three dimensional models; Vision; Biomechanical modelling; Position-based dynamics; Surgical planning; Pneumoperitoneum
• ISSN: 1861-6410; 1861-6429; 1861-6429
• DOI: 10.1007/s11548-019-01924-2

Purpose The aim of this study is to propose a model that simulates patient-specific anatomical changes resulting from pneumoperitoneum, using preoperative data as input. The framework can assist the surgeon through a real-time visualisation and interaction with the model. Such could further facilitate surgical planning preoperatively, by defining a surgical strategy, and intraoperatively to estimate port positions. Methods The biomechanical model that simulates pneumoperitoneum was implemented within the GPU-accelerated NVIDIA FleX position-based dynamics framework. Datasets of multiple porcine subjects before and after abdominal insufflation were used to generate, calibrate and validate the model. The feasibility of modelling pneumoperitoneum in human subjects was assessed by comparing distances between specific landmarks from a patient abdominal wall, to the same landmark measurements on the simulated model. Results The calibration of simulation parameters resulted in a successful estimation of an optimal set parameters. A correspondence between the simulation pressure parameter and the experimental insufflation pressure was determined. The simulation of pneumoperitoneum in a porcine subject resulted in a mean Hausdorff distance error of 5–6 mm. Feasibility of modelling pneumoperitoneum in humans was successfully demonstrated. Conclusion Simulation of pneumoperitoneum provides an accurate subject-specific 3D model of the inflated abdomen, which is a more realistic representation of the intraoperative scenario when compared to preoperative imaging alone. The simulation results in a stable and interactive framework that performs in real time, and supports patient-specific data, which can assist in surgical planning.