A computer-assisted internal examination training system using both anatomical and virtual models

Abstract

For obstetricians and midwives, 'internal examination' refers to an important diagnostic technique in which the progress of labor is examined using the index and middle fingers inserted into the vagina or rectum. Training of this internal examination technique has been commonly performed using a model of the human body (manikin). However, with this method, it was impossible to determine visually where and how the examining fingers are touching, making it difficult for trainers to teach advanced examination skills efficiently and evaluate training achievements. Against this background, we have developed a training system for internal examination that enables simulation of normal and abnormal conditions of labor by detecting the position and direction of the examining fingers in real-time via tactile and visual perceptions using anatomical and virtual models. This system allows trainees to experience both normal and abnormal fetal descent into the pelvis. In addition to support the abnormal conditions, we propose the unique measurements function using magnetic sensors, in order to estimate the precise baby status, such as a gap of the uterine ostium or baby head. We conducted a survey of eight students at our university, and made inquiries for our system, and evaluated it for understanding where the position of ischiatic thor (spinal ischium), baby head, and uterine ostium. The result of the several questions shows that the understanding of all students is improved by using our system. Keywords: a training system, internal examination, magnetic sensor, manikin, virtual models, virtual reality. INTRODUCTION 1Previously developed training systems for internal examination include our own system [1-3], ePelvis [4][5][6] developed by a group from Stanford University, and the peripartum diagnosis/delivery assistance training system [7], and the SIMone Childbirth Birthing Simulator/Manikin [8]. The ePelvis is a prototype pelvic simulator, and it attaches several sensors inside the mother's body (manikin). The peripartum diagnosis/delivery assistance training system is basically a visual learning system using video images, and is suitable for teaching and explanation but not for training of the internal examination itself. The SIMone is a model of a female abdomen with a vulva and the spinal ischium as landmarks. Inside the simulator is a fetal head, and the 19" screen monitor shows the position and approach of the head. The ePelvis, the peripartum diagnosis/delivery assistance training system, and the SIMone are not suitable for close monitoring of fingers and the evaluation of examination techniques. Our approach in our training systems described in [1][2][3] is different in comparison with the three systems, ePelvis, the peripartum diagnosis/delivery assistance training system, and the SIMone. We utilize magnetic sensors that are attached with two fingers, and monitor the motions of two fingers in internal examination. Our previous system was used to simulate the normal labor condition and thus was not suitable...