Almost The Real Thing

As an alumnus of Rensselaer Polytechnic Institute (RPI) in Troy, NY, I am always proud to hear of the research and progress being made by the faculty and scientists at the school. Recently an article was written in the Wall Street Journal about the research on "virtual patients" being done at RPI.

^{Virtual Patient. Image Credit: Consortium of Computation Human Phantoms.}

The Problems

Timely And Efficient Testing

All pharmaceuticals, medical procedures, and medical devices (from band aids to knee implants) undergo extensive and expensive trials before being approved for use in patients. Much of the time, testing on patients is too dangerous so it's done in vitro or on animals. But this leaves a gap in observing the results of the medicine in higher risk patients such as children and pregnant women. Virtual patients could allow medical-device companies to test new products earlier, and on a wider range of patients, helping the devices get to market more quickly and cheaply, according to the Food and Drug Administration.

Practice Time For Surgeons

The best teacher is experience, and a not all surgeons are getting enough practice. One study reports a complication rate of 14.7 per 1,000 patients for surgeons who have performed less than 100 such procedures, in contrast to 3.8 complications per 1,000 procedures for more experienced surgeons. Another report, by the Institute of Medicine, cites "error in the performance of an operation" as a major contributor to the approximately 98,000 deaths per year attributable to medical errors-a number that exceeds deaths from motor vehicle accidents, breast cancer, or AIDS. Considering that the skill of a surgeon is the single most important factor determining the success of minimally invasive surgical procedures, having student surgeons practice virtually is a much safer option.

The Science

In 2010, RPI announced the opening of the new Center for Modeling, Simulation, and Imaging in Medicine (CeMSIM) within the School of Engineering. The goal of the center was to develop advanced modeling, simulation, and imaging technology for health care, and transition those technologies to clinical practice. Through interdisciplinary work, advances in imaging would be mixed with investigations in improved diagnosis, surgical, and noninvasive techniques as well as high-performance computing and visualization.

The center stems from the work of Dr. Suvranu De, who in 2006 was developing a new approach to training surgeons using a virtual simulator. The simulator allows surgeons to touch, feel, and manipulate computer-generated organs with actual tool handles used in minimal invasive surgery (MIS). Also in 2010, the touch-sensitive virtual reality simulator technology was being tested by medical students. The simulator is designed to train surgeons on laparoscopic surgery, which reduces the need for large incisions, resulting in short healing time and less scaring. The virtual reality tool will help surgeons to train on the basics such as cutting specific patterns, tying knots, stitching, and manipulating very small items through a simulator that will let them feel the lifelike toughness, sponginess, and resistance of virtual tissue. The goal is to standardize the training and certification for surgeons before they can perform the surgery on patients.

^{A medical student from Beth Israel Deaconess Medical Center is shown testing the new haptically-enhanced virtual surgery simulator. Image Credit: Rensselaer Polytechnic Institute}

And here is a video of the student doing the procedure.

Earlier this year, Dr. De was awarded a $2.7 million grant from the National Institute of Health to build upon his virtual organ technology to that of a virtual operating room. This system will expand upon the current simulators which focus on enhancing and assessing a surgeon's hand movements to a system which encourages understanding of the overall procedure as well as the cause-and- effect of their actions. The system also has a "mentor" built in to offer tips and guidance during the "procedure".

The Next Step

The grant money is also going towards furthering the characteristics of the virtual patient, such as breathing in real time. Adding the fourth dimension to the patient could significantly improve the accuracy and effectiveness of radiation treatment for lung and liver cancers. Professor George Xu is working with De to develop the 4-D Visible Photographic Man (VIP-Man). The research is done under the premise that live patients are not static beings and moving organs, such as the heart and lungs, can affect the quality of radiation treatment or imaging of tumors. Virtual patients are realistic-looking computerized models. They use medical data and computer software and graphics to mimic the look and feel of real people.

Virtual Lungs. Image Credit Rensselaer Polytechnic Institute

Xu has been trying to determine accurate and effective radiation dosages for treatments and imaging as well as the risk of heart devices like a defibrillator in child. The challenge comes in accounting for various body types, and sizes, and the condition of the patients such as if they are a child or pregnant. It's too risky to test for radiation exposure on higher risk patients and the 4-D VIP-Man will allow doctors to accurately predict and monitor the movements of the lungs, liver, kidney and heart to provide the most effective treatment possible at any given time.

The key challenge in this project is to develop the algorithms that will make the virtual lungs and adjacent tissues move in real time according to realistic tissue biomechanical properties, De says. Cu will also continue to work on the 3-D VIP Man to create a "family" of virtual patients in collaboration with the Consortium of Computational Human Phantoms.

So it's always nice to hear that my alma mater is doing great things, and I'm even more excited about the promises that this research holds for creating safer products, treatments and medical procedures.

Resources

Scientists Find Safer Ways To Test Medical Procedures

"Virtual Operating Room" To Sharpen Surgeons' Smarts and Skills

Designing Touch-Sensitive Virtual Reality Tools To Train and Test Tomorrow's Surgeons

Digital Surgery With Touch Feedback Could Improve Medical Training

The "Virtual Patient" To Simulate Real-Time Oran Motions