"The future of surgery is not about blood and guts; the future of surgery is about bits and bytes.”
/Dr. Richard Satava/

Wednesday, December 26, 2007

Happy Holidays

Wishing a merry merry Christmas and a happy New Year to all my dear Readers!

The neurosurgery robot project I.

Neurosurgery requires extreme precision and accuracy. Normally any procedure takes hours as the doctor has to move the surgical equipment very carefully. This means this is a great area for CIS where we can fully take advantage of the features offered by the robots. This was the idea that made the people at ERC begin the NeuroMate project I am involved in.
The NeuroMate robot was originally developed by Integrated Surgical Systems Inc. for MRI based biopsy taking. (See previous post.) The present project is focusing on skull base surgery, to significantly reduce the time of operation by offering surgeons a precise and safe drilling tool. We use compliant motion control which means the surgeon is fully in charge of the control of the robot by holding the drilling tool mounted at the end of the robotic arm. The 6 DOF force sensor added gathers information on the surgeon's hand movement in real time, and moves the robot to follow it. This is a safe way to support drilling and in the mean time reduce tremor.
The most important added value of the system is the use of Virtual Fixtures. VF concept was first introduced by Rosenberg in 1993, and further developed by Dr. Taylor and Dr. Kazanzides to be used in cooperative CIS. The VF is a virtually defined spatial area where the robot is allowed to move. It is drawn on a 3D model of the patient, usually the MRI based models built for records taken soon before surgery. We use the open source 3D slicer to import the MRI data and to define the VFs. Applying the VF during surgery means, that whatever the physician wants to do the robot will not follow if it results a motion leaving the safe area. What is more, there is a proportional scale down in speed in the proximity of the boundary. This safe way allows the surgeon to automatically avoid critical anatomical areas, and to speed up the drilling process significantly. Advantage for the patient and for the surgeon as well.
To be continued…

Thursday, December 20, 2007

The snake-like robot

One of the grandiose research project at CISST is the development of the snake-like robot. These are highly dexterous, flexible surgical instruments, compatible with the da Vinci system. It can help surgeons to operate though the throat of the patient, as the tool can bend in an S shape, while keeping the original 6DOF controllability. This may be an important and convenient way to perform minimally invasive surgery. The tool is MRI compatible, and includes force sensors to help e.g. the difficult procedure of knot tying. The robot has innovative features, it uses push-pull superelastic backbones and actuation redundancy and eliminates dependency on precision joints and backlash. It was designed to be simple to manufacture and even downs-scalable to smaller diameters. Several phantom tests have already been performed, and clinical trials are to follow.

Further readings: ppt presentation on the control behind the robot, an article on the system and a showup in the New York Times.

Sunday, December 9, 2007

The Haptic Exploration Laboratory at JHU

The Haptic Exploration Laboratory works with both robotic haptics and human-machine haptic interfaces. In the area of robotic haptics, they enable robots to explore the world through touch, using specialized robotic fingers and sensors and the appropriate planning and control. They are developing new finger designs and algorithms for autonomous and teleoperated haptic exploration. In the area of human-machine haptic interfaces, haptic interfaces are used to add the sense of touch to virtual and teleoperated environments. By creating physically-based mathematical models of interactions in real environments, they can enhance the realism of virtual environments. In addition, haptic feedback and active augmentation modes can improve the performance of robotic assistants in tele- and cooperative manipulation. These systems are evaluated using control theoretic and experimental approaches. This research has applications in many areas, including computer-assisted and simulated surgery, autonomous exploration of hazardous or remote environments, undersea salvage, enabling technologies, and manufacturing and design. Sponsors of their work include NSF, NIH and the Whitaker Foundation. The lab director is Dr. Allison Okamura.
/ Source: Haptics site/