Development of a robotic system with six-degrees-of-freedom robotic tool manipulators for single-port surgery.

Background: Current robotic systems have limitations for single-port surgery (SPS) because the instruments are large, the arms collide and the field of vision requires manual readjustment. We have developed an SPS robotic system that manipulates the vision field.

Methods: The master-slave system included a six degrees of freedom (DOFs) tool manipulator, an easy set-up mechanism, a flexible shaft drive with sufficient DOFs and a vertical arrangement for improved vision.

Comparison of transtibial and transportal techniques in drilling femoral tunnels during anterior cruciate ligament reconstruction using 3D-CAD models.

Purpose: The purpose of this study was to assess the differences in bone tunnel apertures between the trans-accessory medial portal (trans-AMP) technique and the transtibial (TT) technique in double-bundle anterior cruciate ligament reconstruction. The extent of ovalization and the frequency of overlap of the two tunnel apertures were compared.

Methods: The simulation of femoral tunnel drilling with the TT and the trans-AMP techniques was performed using three-dimensional computer aided design models from two volunteers.

Development of a 6-DOF manipulator driven by flexible shaft for minimally invasive surgical application.

This paper presents a 6-DOF manipulator which consists of four parts, 1-DOF translational joint, two 2-DOF bending joints (segment1 and segment2), and 1-DOF rotational gripper. The manipulator with "flexible shaft and Double Screw Drive (DSD) mechanism" structure can obtain omni-directional bending motion through rotation of flexible shafts. In the first prototype, the flexible shafts were connected directly with the actuators in the manipulator.

Intercondylar roof impingement after anatomic double-bundle anterior cruciate ligament reconstruction in patients with knee hyperextension.

Background: Although an anatomically placed graft in anterior cruciate ligament (ACL) reconstruction is reported to have a low risk of roof impingement, which may cause deterioration of the graft or an extension deficit, the incidence of roof impingement by these grafts has not been evaluated in hyperextensible knees.

Purpose: To evaluate the incidence of roof impingement by the native ACL in hyperextensible knees and to examine the risk of roof impingement by anatomic placement of the ACL graft in hyperextensible knees.

Study Design: Controlled laboratory study.

Use of puncture force measurement to investigate the conditions of blood vessel needle insertion.

Central venous catheterization involves venous puncture and catheter insertion for transfusions. Quantitative conditions that facilitate insertion of the needle, such as the angle and velocity of insertion, have not been clarified. We previously developed a robotic system for guiding the needle along a specified puncture path with high precision and are currently implementing a hardware design for a robotic system to assist in blood vessel puncture.

The concept and feasibility of EXPERT: intelligent armrest using robotics technology.

Background: Continuous precise motions are required in microneurosurgery to provide high-quality surgical results. Stabilizing the surgeon's arm and reducing fatigue during surgery are expected to improve the precision of microsurgical procedures. We have developed an intelligent armrest, EXPERT, that follows the surgeon's hand and fixes at an adequate position automatically using robotics technology.

New detachable occlusion balloon unit for transrectal natural orifice translumenal endoscopic surgery.

Introduction: Transrectal natural orifice translumenal endoscopic surgery (NOTES) requires a good endoluminal view and adequate intrarectal bacterial clearance in the working area. We developed a new occlusion balloon unit with an easily detachable inflation device, which allows the surgeon a clear working area distal to the balloon.

Material And Methods: The effectiveness of the sealing balloon and the extent of macroscopic and histopathological injury to the bowel wall at the site of balloon placement were examined in 12 pigs.

In vivo experiments of a surgical robot with vision field control for Single Port Endoscopic Surgery.

Recently, robotics systems are focused to assist in Single Port Endoscopic Surgery (SPS). However, the existing system required a manual operation of vision and viewpoint, hindering the surgical task. We proposed a surgical endoscopic robot for SPS with dynamic vision control, the endoscopic view being manipulated by a master controller.

Design of a surgical robot with dynamic vision field control for Single Port Endoscopic Surgery.

Recently, a robotic system was developed to assist Single Port Endoscopic Surgery (SPS). However, the existing system required a manual change of vision field, hindering the surgical task and increasing the degrees of freedom (DOFs) of the manipulator. We proposed a surgical robot for SPS with dynamic vision field control, the endoscope view being manipulated by a master controller.

A surgical robot with vision field control for single port endoscopic surgery.

Background: Robotic end-effectors for single port endoscopic surgery (SPS) require a manual change of vision field that slows surgery and increases the degrees of freedom (DOFs) of the manipulator.

Methods: A new surgical prototype robot has dynamic vision field control and a master controller to manipulate the endoscopic view. It uses positioning (4 DOF) and sheath (2 DOF) manipulators for vision field control, and dual tool tissue manipulators (gripping, 5 DOF; cautery, 3 DOF).

Autonomous avoidance based on motion delay of master-slave surgical robot.

Safe use of master-slave robots for endoscopic surgery requires autonomous motions to avert contact with vital organs, blood vessels, and nerves. Here we describe an avoidance control algorithm with delay compensation that takes the dynamic characteristics of the robot into account. To determine the operating parameters, we measured frequency characteristics of each joint of the slave-manipulator.

Telesurgery of Microscopic Micromanipulator System "NeuRobot" in Neurosurgery: Interhospital Preliminary Study.

Object: Robotic surgery can be applied as a novel technology. Our master-slave microscopic-micromanipulator system (NeuRobot), which has a rigid endoscope and three robot-arms, has been developed to perform neurosurgical procedures, and employed successfully in some clinical cases. Although the master and slave parts of NeuRobot are directly connected by wire, it is possible to separate each part and to apply it to telesurgery with some modifications.