Many innovative surgical devices based on novel technologies and techniques have been studied to offer secure diagnosis and less invasive treatment with fewer complications. Before these devices are used clinically, their safety must be validated using various methods to simulate the clinical situation with reasonable accuracy. In this paper, we focused on mechanical intervention and surveyed various preclinical studies, which assessed the collateral damage accompanied with the use of these devices. This review paper is especially intended for a reader who (1) develops or researches on surgical devices, (2) intends to implement or commercialize innovative surgical devices or medical technologies to the society, and (3) wants to identify safety validation methods that are an index for surgical devices approval systematically. All studies were categorized according to their types of intervention (grasping, stretching, needle, and shock wave) so that the readers can efficiently find similar or related assessment methods. In these studies, the intervention was applied to a computer model and/or animal model in vivo and/or ex vivo. The damage was evaluated by one or more sub-assessments including tissue function and tissue structure as well as cellular functional and cellular structural assessments such as histological observations. Some of these studies attempted to clarify effective intensity and distribution of intervention, whose collateral damage was acceptably small. Therefore, such procedures or devices were proved to be effective and safe. Finally, considering all studies, we have tried to comment on the future challenges in this field.

View full abstract

Although CT-based navigation is a well-documented assist tool for optimal implant placement in primary total hip arthroplasty (THA), accuracy for implant placement in revision THA (RevTHA) is not well-established. The purpose of the present study was to investigate the navigation accuracy in RevTHA. This study examined 16 hips that underwent RevTHA using the CT-based navigation system. 49 hips that underwent primary THA using the same navigation system were selected as a control group. The cup orientations were measured from the postoperative CT images after 3D matching was performed to adjust the pelvic orientation between the preoperative and postoperative CT images. Then clinical accuracy (difference between preoperative planning and postoperative CT measurement) and measurement error (difference between intraoperative record and postoperative CT measurement) were compared between RevTHA and control groups. The clinical accuracy of cup inclination and anteversion was 1.4±1.0°and 1.3±1.4°, respectively. The measurement error of cup inclination and anteversion was 1.6±1.3°and 1.0±1.1°, respectively. There were no significant differences between the groups in absolute differences and variations of the cup alignments. Our results suggested that the accuracy of the CT-based navigation system for the RevTHA was equal to that for the primary THA by devising the registration method.

View full abstract

Introduction : We propose a new contactless coagulation method for a surgical energy device. Steam jet performs instantaneous wide-ranging coagulation and cauterization at without carbonization of biological tissue.
Materials & Methods : The feasibility of proposed method was evaluated with prototyped steam jet coagulator. In-vivo experimental simulations of laparoscopy were conducted using porcine.
Results : Coagulation and cauterization was successfully performed on the wound at a porcine spleen in 15.3 seconds on average with the exposure to the steam jet. In addition, we confirmed its availability on a surgical robot.
Conclusion : Feasibility of proposed method was confirmed through the experiments. Improved quality of steam, controllability of heat affected zone, avoidance of visibility obstructions and pathological study of steam coagulation effect are required for further development.

View full abstract