Virtual reality simulation of regional anesthesia for training of residents

For patients with intractable pain, successful management can increase their quality of life. In the case of unlocalized abdominal pain resulting from non-resectable abdominal cancer; the administration of an anesthetic agent to the celiac plexus is often prescribed by physicians. The celiac plexus block is regarded as an effective, and safe procedure in the hands of a skilled clinician, with a relatively low rate of complications. However, sensitive surrounding structures and the lack of suitable "hands-on" experience present obstacles to successful training of the procedure. Moreover radiological guidance is often used by less confident, inexperienced physicians, increasing procedure time and exposing the patient to ionizing radiation. In conjunction with Mayo\´s Pain Clinic and Department of Anesthesiology, the Mayo Biomedical Imaging Resource has developed a virtual reality anesthesiology training simulation designed to provide effective visualization and natural haptic feedback. Visualization of the anatomy involved in the celiac plexus block is a crucial aspect in training for proper performance of the block. Actual experience performing the block is also a primary factor related to safety and efficacy of the procedure. To address these two aspects of training, we have developed a virtual environment that presents patient specific anatomic visualization to the resident via an intuitive interface, and provides natural haptic feedback using forces calculated from patient CT scans. This work reports on the architecture of the simulator detailing the process of creation of patient specific anatomic modeling, and development of haptic force feedback models from empiric biomechanical data collected during performance of the celiac plexus block. Significant interest in the simulator as a training system was expressed in a survey conducted after the presentation of the system to approximately 100 practising anesthesiologists. Sixty-four percent indicated that the system would greatly enhance resident training, and forty two percent indicated they would use the simulator to rehearse before performing the procedure on patients with difficult or unusual anatomy.