Acoustic MedSystems proposes to develop an image-guided robot for MRI, CT and fluoroscopy guidance. The robot will be used for brain, prostate, liver, kidney, breast, and spine intervention. A general purpose robotic manipulator will be designed with development and implementation of a specific configuration for interventional medical biopsy and treatment use. The proposed program represents an innovation in clinical robotic interventions in several ways. It includes a cable-controlled drive and gear assembly linkage, so that actuators can be displaced from the robot motors and controller as much as several meters. Fiber-optic position sensors eliminate all electronics for sensing from the robot. These design innovations will make it possible to build small, purpose-specific robots. Although our proposed new robotic design and implementation is very well-suited to medical interventions, the concept is useful for a broad range of applications extending well beyond this initial application area. Multiple applications of the proposed single drive, multiple DOF robots can benefit from applying this concept and using possible standardized components that may be implemented with it. AMS is engaged in multiple medical research projects that include medical robots, and hence has become aware of many complications of using robots in clinical settings. We have a developed a conceptual approach for a robotic drive system that addresses these clinical issues, while also offering other design benefits and possible cost and size reductions for medical and non-medical robotics applications.
Minimally-invasive procedures are pervasive in medicine and further, needles and catheters are among the least invasive vehicles for accessing the interior of the human body. They can be used for diagnoses (e.g. biopsy), as well as interventions (e.g. injection of liquid therapeutic agents, insertion of surgical tools, radioactive seed implantation, thermal therapy, etc.). Accuracy in targeting the desired location is essential in nearly all procedures to ensure therapeutic or diagnostic efficacy and safety. It has been well-established that image-guided robotic devices are useful for aligning tools accurately with preoperatively planned insertion trajectories. A single robotic insertion has been shown to exhibit approximately half the error of a manual insertion by an experienced surgeon under Ultrasound guidance. However, initial robotic alignment of the device toward its target can never completely eliminate tip placement error, because there is no means of compensation for registration error (which can never be completely eliminated) or perturbations that occur during insertion, including tissue deformation, patient motion, breathing, deflection of a needle at membrane boundaries, etc. Furthermore, there are some locations that are inaccessible to straight-line trajectories (e.g. the pubic arch can obstruct a portion of the prostate in some patients during brachytherapy). These factors have motivated the recent development of steerable needles and surgical tools, and many mechanisms for steering have been proposed. To date, research has focused on tip placement accuracy assessment and model validation, which are necessary first steps toward interventional and diagnostic goals. However, inherent technical difficulties in existing systems have limited the efficacy and application of procedures, namely, 1) lack of adequate image guidance and 2) inadequate control of placement. Furthermore a third and very important issue is that in many cases, site access is limited, making the need for remote device control and location of drive mechanisms (motors, etc.) of paramount importance. The goal of this project is to address these three limitations by creating a system that combines a proprietary general purpose multi-degree-of-freedom precisely controllable robotic mechanism with e3D spatial tracking and image guidance. The proposed integrated robotic system will enable highly accurate tool placement and provide greater control at the target site. Compared to existing percutaneous techniques, this system could improve diagnostic accuracy, treatment efficacy, limit the risks of complications, and enable treatment in those patients who otherwise would have been precluded from the procedure.
