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

Sunday, April 26, 2009

Robotic surgery in space III.

This post deals with the different problems emerging with telesurgery through long distances and in space.
The primary difficulty with teleoperation beyond Earth orbit is communication lag time or latency. Radio and microwave frequency signals propagate at almost the speed of light in space, however already in the range of long distance manned missions, several minutes of latency can be experienced. Planet Mars orbit 56 000 000 km to 399 000 000 km from Earth which means a 6.5 to 44 minutes of delay in transmission. In addition, for about two weeks every synodic period, when the Sun is in between Earth and Mars, direct communication can be blocked. In addition, the compression and decompression of the video stream takes app. 1 200 ms. NASA has conducted several experiments to examine the effect of latency on the performance in the case of telesurgery and telementoring. The NASA Extreme Environment Mission Operations (NEEMO) take place on the world’s only permanent undersea laboratory, Aquarius. It operates a few kilometers away of Key Largo in the Florida Keys National Marine Sanctuary, 19 meters below the sea surface. A special buoy provides connections for electricity, life support and communication lines, and a shore-based control center supports the habitat and the crew. Aquarius hosts high-tech lab equipment and computers, enabling astronauts, engineers and marine biologists to perform research, sea exploration and simulated space missions. 12 NEEMO projects have been organized since 2001, and there have been three projects focusing on teleoperation recently.
The 7th NEEMO project took place in October 2004. The mission objectives included a series of simulated medical procedures with Zeus, using teleoperation and telementoring [10]. The four crew members (one with surgical experience, one physician without significant experience and two aquanauts without any medical background) had to perform five test conditions: ultrasonic examination of abdominal organs and structures, ultrasonic-guided abscess drainage, repair of vascular injury, cystoscopy, renal stone removal and laparoscopic cholecytectomy. The Zeus robot was controlled from the Centre for Minimal Access Surgery, Ontario, 2500 km away. The signal delay was tuned between 100 ms and 2 s to observe the effect of latency. The results showed that the non-trained crew members were also able to perform satisfyingly by exactly following the guidance of the skilled telementor. They even outperformed the non-surgeon physician, but fell behind the trained surgeon. Scientists also compared the effectiveness of the telementoring and the teleoperated robotic procedures, and even though the teleoperation got slightly higher grades, it also took a lot more time to complete.
During the 9th NEEMO in April 2006, the crew had to assemble and install an M7 mobile surgical robot, and perform real-time abdominal surgery on a patient simulator. Throughout the procedure, the time delay went up to 3 s using a microwave satellite connection to mimic the Moon-Earth communication links. The M7 robot was also used to arrange and manipulate rock samples form the ocean’s ground. In another experiment, pre-established two-way telecom links were used for telementoring. The crew had to prove the effectiveness of telemedicine through the assessment and diagnosis of extremity injuries and surgical management of fractures. The effects of fatigue and different stressors on the human crew’s performance in extreme environments were also measured. Each of the 4 astronauts taking part in the experiment had to train at least 2 hours with the small wheeled MIS robots designed at the University of Nebraska.
The 12th NEEMO project ran in May 2007, and one of its primary goals was to measure the feasibility of telesurgery with the Raven and the M7 surgical robots. NASA sent a flight surgeon, two astronauts and a physician into the ocean. Suing operations were performed on a simulated patient in zero gravity environment to measure the capabilities of surgeons controlling the robots from Seattle. A group of three professionals guided the robot, using a commercial Internet connection, and transmitting the signals on a wireless connection to the buoy of the sea habitat. The communication lag time was increased till up to 1 s. The robots had to perform several simple tasks, such as suturing and Fundamentals of Laproscopic Surgery. The first demonstration of an image-guided remote surgery was presented with the M7 robot (using a portable ultra sound system), and live broadcasted on the American Telemedicine Conference in Nashville, Tennessee. The M7 was able to insert the needle into a simulated vessel by itself. (See this video report.)
Important lessons have been learned throughout the NEEMO missions. Medical Operation Requirements Documents of upcoming space missions are composed using the experience gained through these projects.

To ensure high quality visual and tactile feedback, high sampling rate must be used (app. 1 ms). Along with the high definition video feedback this has a significant bandwidth demand. Under regular circumstances a 10 Mbps connection is already suitable for teleoperation, however in the case of high definition, multimodal equipment a 40 Mbps two-channel link would be required. This may not cause any problem on the ISS that has been equipped with a 150 Mbps connection in 2005, but in the case of a Mars mission, NASA only plans to develop a 5 Mbps connection by 2010 as a part of the new space communication architecture, and upgrade it to 20 Mbps by 2020.
To meet the special communication requirements in space, the Space Communications Protocol Standards (SCPS) was developed and tested by the U.S. Department of Defense and NASA in the 1990s. SCPS uses similar architecture to TCP/IP, but it is more effective in handling latency created by long distance transmissions and the noise associated with wireless links. The SCPS exists as a complete ISO standard, and even fits the U.S. Military Standards.

See our previous reports here and here!

Image credit: SRI Inc.

Saturday, April 18, 2009

MedGadget blog

MedGadget is a great source of information about medical innovations and technology development. Here are a couple of recent headlines relevant to CIS:

Saturday, April 11, 2009

Robotic surgery in space II.

Performing surgery in space raises many concerns and issues, with or without a robot.
The Russians performed some animal surgery (rabbit laparotomy) in microgravity. The first one was performed in 1967 by a Soviet team during parabolic flights.
The first European operation in weightlessness was performed in 2003 on a rat on board of ESA’s Zero G plane (a modified Airbus A-300). In 2006, surgeons removed a cyst from a patient arm, while the Zero-G aircraft was performing 25 parabola curves, providing 20–25 s of weightlessness every time (New Scientist, 2006). ESA planned to perform teleoperation in 2008 with a robot—controlled through satellite connection, but the project got delayed.
An experiment involving a surgical procedure in space took place in a rat model, during the Neurolab Mission (STS 90) on the U.S. Space Shuttle in 1998. The open procedure did not involve the abdominal or thoracic cavities (Panait et al. 2004). NASA had its first zero gravity surgery experiment in late September 2007 (Popular Mechanics, 2007). On a DC-9 hyperbolic aircraft suturing tasks were performed with an M7 robot. The performance of classical and teleoperated robotic knob tying were measured (SRI communications). Both the master and the slave devices were equipped with acceleration compensators, otherwise
it would have been almost impossible to succeed on the tasks. The results showed that humans can still better adapt to extreme environments, however, advanced robotic solutions do not fall far behind.
Besides, many laparoscopic simulation procedures took place during parabolic flights, and NASA tested robots in its Aquarius underwater habitat. (See next post for deatils.)

Probably the most important professional in the field of telesurgery and advocate of space robotic surgery is Richard Satava. He devoted his life to become the first to operate a human in space, and even though he qualified as a NASA flight surgeon, never got assigned to a mission. Later, he realized the importance of telesurgery and took part in the development of early surgical robot prototypes with DARPA and SRI. He still wants to be the first to remotely operate on someone in space.
"Richard M. Satava, MD, FACS is Professor of Surgery at the University of Washington Medical
Center, and Senior Science Advisor at the US Army Medical Research and Materiel Command in Fort Detrick, Maryland. Rick was the surgeon on the team that developed the first surgical robot, and developed the first virtual reality surgical simulators. For the past 15 years he has been at DARPA, and now US Army Medical Research Command, funding leading edge medical technologies at tens and hundreds of millions of dollars a year. Prior positions include Professor of Surgery at Yale University and a military appointment as Professor of Surgery (USUHS) in the Army Medical Corps assigned to General Surgery at Walter Reed Army Medical Center and Program Manager of Advanced Biomedical Technology at the Defense Advanced Research Projects Agency (DARPA)."
He has an amazing list of publications, and on his webpage, many of his eye catching presentations are available. You can even listen to him: a presentation from 2007 at UCF, another talk from 2008 at a Business Innovation Factory meeting and a great interview with him. Finally, a post on his talk at the BioRob2008 can be found here.

See our previous report here!

Thursday, April 2, 2009

The new Da Vinci Si system

Update: official video of da Vinci Si.
Today, Intuitive Surgical announced it's new da Vinci surgical system, called Si. The first press release does not tell much about the hardware development, but as the 4-arm da Vinci-S can be upgraded to Si, the new system might get wide-spread quickly. More details are available on Intuitive's website. The Si got the FDA approval in February, supporting its fundamental equivalence to the prior system. The major changes include the redesign of the master consol, introducing more ergonomic control (less buttons) and a multi-functional touch screen.
"The da Vinci Si System introduces several new features designed to provide additional clinical benefits and operational efficiencies: Enhanced 3D HD resolution offers superior visual clarity of target tissue and anatomy, potentially allowing for greater surgical precision; an updated and simplified user interface enhances operating room efficiency; newly upgradeable architecture and compatibility with existing OR suite technology facilitates the seamless integration of the da Vinci Si System into the OR of the 21st century; an optional dual console allows a second surgeon to provide a da Vinci-enabled assist and may also facilitate teaching da Vinci Surgery; and finally, the addition of new ergonomic settings to the surgeon console allows greater surgeon comfort during procedures. The da Vinci Si System retains and builds upon the core technology at the heart of the existing da Vinci(r) and da Vinci(r) S(tm) Systems. This includes advanced 3D HD visualization with up to 10x magnification, offering surgeons an immersive view of the operative field, superior to that offered by conventional surgical approaches; EndoWrist(r) instrumentation, providing da Vinci surgeons with natural dexterity and range of motion far greater than even the human hand; and Intuitive(r) motion technology, which replicates the operative experience and control of open surgery by preserving natural eye-hand-instrument alignment and intuitive instrument control."
"The Intuitive Surgical Endoscopic Instrument Control System (Model IS3000) is intended to assist in the accurate control of Intuitive Surgical Endoscopic Instruments including rigid endoscopes, blunt and sharp endoscopic dissectors, scissors, scalpels, ultrasonic shears, forceps/pick-ups, needle holders, endoscopic retractors, stabilizers, electrocautery and accessories for endoscopic manipulation of tissue, including grasping, cutting, blunt and sharp dissection, approximation, ligation, electrocautery, suturing, and delivery and placement of microwave and cryogenic ablation probes and accessories during urologic surgical procedures, general laparoscopic surgical procedures; gynecological laparoscopic surgical procedures, general cardiovascular and non-cardiovascular thoracoscopic surgical procedures, and thoracoscopically assisted cardiotomy procedures. The system is indicated for adult and pediatric use. The system can also be employed, with adjunctive mediastinotomy to perform coronary anastomosis during cardiac revascularization. It is intended for use by trained physicians in an operating room environment in accordance with the representative specific procedures set forth in the Professional Instructions for Use. "

More pictures are available at Intuitive.
Post at MedGadget.