Prediction of respiratory motion has the potential to substantially improve cancer radiation therapy. A nonlinear finite element (FE) model of respiratory motion during full breathing cycle has been developed based on patient specific pressure-volume relationship and 4D Computed Tomography (CT) data. For geometric modeling of lungs and ribcage we have constructed intermediate CAD surface which avoids multiple geometric smoothing procedures. For physiologically relevant respiratory motion modeling we have used pressure-volume (PV) relationship to apply pressure loading on the surface of the model. A hyperelastic soft tissue model, developed from experimental observations, has been used. Additionally, pleural sliding has been considered which results in accurate deformations in the superior-inferior (SI) direction.
Completed Projects
While most commercially available surgical simulators (Gen1) are intended for psychomotor skill training, adult learning theory and literature in cognitive science indicate that immersive training is most effectively imparted in its natural context. Following this paradigm, the next generation (Gen2) simulators are being developed which also impart cognitive fidelity and feedback during training.
Working closely with the Fundamentals in Laparoscopic Surgery (FLS) committee, Harvard Medical School and Tufts University, this project aims at developing and validating a virtual reality simulator for the FLS tasks (peg transfer, pattern cutting, ligating loop, suturing with intracorporeal and extracorporeal knot tying).
Electrosurgery is now becoming universally accepted as the technique of choice in most minimally invasive surgical (MIS) procedures for achieving a variety of tissue effects ranging from dissection to hemostasis (control of bleeding) using high frequency electrical energy. However, there exists no standardized curriculum or training regimen outside the operating room (OR), for the surgical community to safely and effectively use the complex electrosurgical instruments. It is anticipated that a virtual reality (VR)-based trainer, with visual and haptic (touch) feedback, will be invaluable for electrosurgical skill training, allowing the trainees to attain competence in a controlled environment.
This project aims at developing and validating a virtual reality-based simulator for the laparoscopic gastric banding procedure. Preliminary clinical validation studies have been performed in 2010 at Harvard Medical School.
Natural Orifice Translumenal Endoscopic Surgery (NOTES) is an emerging surgical paradigm, where peritoneal access is achieved through one of the natural orifices of the body. It is being reported as a safe and feasible surgical technique with significantly reduced external scarring. Virtual Translumenal Endoscopic Surgical Trainer (VTEST™) is the first virtual reality simulator for the NOTES. Through collaboration with clinical leaders in the NOTES field, the VTEST™ simulator was designed to train surgeons to successfully complete a hybrid transvaginal NOTES cholecystectomy procedure.