Paging Dr. Roboto
Of all the issues facing humanity, none is as personal and encompassing as the field of medicine and health. From interactions at the cellular level to helping people with paralysis walk, Vanderbilt engineers look at the problem and seek solutions. In many cases, they draw on the culture of cooperation, integration and accessibility among departments and also between the Schools of Engineering and Medicine and Vanderbilt University Medical Center to allow solutions to move from the bench to the bedside quickly and efficiently.
Not too far in the future, robots will steer needles in your brain to remove blood clots; people with paraplegia will wear powered exoskeletons to walk; and ultra-miniaturized snake robots will remove tumors from the bladder and other body cavities. This isn't science fiction it is some of the medical robotics research currently happening at Vanderbilt.
One of those leading the way is Michael Goldfarb , the H. Fort Flowers Professor of Mechanical Engineering and director of the Center for Intelligent Mechatronics. He has successfully developed a bionic arm powered by hydrogen peroxide, the first lower-limb prosthetic with powered knee and ankle joints, an exceptionally dexterous artificial hand, and a powered exoskeleton that allows people with paraplegia to stand and walk. To watch a video on his exoskeleton research, go to vu.edu/goldfarb.
As one of the primary centers in the country for basic research in medical robotics, Vanderbilt has drawn additional faculty and projects. Assistant Professor of Mechanical Engineering Robert Webster develops surgical robotics and related devices that make surgery less invasive and more accurate. Nabil Simaan , associate professor of mechanical engineering, focuses on developing robotic technologies for safe and intelligent surgical interventions including natural orifice surgery. Pietro Valdastri , assistant professor of mechanical engineering, seeks to turn the idea of miniature capsule robots working inside the human body into reality.
Webster's work involves what he calls active cannula, a series of thin, nested curved tubes. By precisely rotating and extending these tubes, an operator can steer the tip to follow a curving path through the body. He's currently working with Assistant Professor of Neurological Surgery Kyle Weaver and graduate student Philip Swaney to investigate using the design to remove blood clots from the brain, which are responsible for approximately 2 million strokes each year worldwide. The number of such clots, intracerebral hemorrhages, is expected to increase as the population ages. The active cannula can also work as a needle-sized robot arm to reach into small spaces in the body. Webster is using it for other surgical applications including reaching down the throat to biopsy challenging lung tumors and is working with Weaver and Assistant Professor of Otolaryngology Paul Russell to thread it through the nostrils to remove pituitary tumors.
Simaan and a team that includes urologic surgeon Duke Herrell have designed a miniaturized telerobotic system that could revolutionize surgery for bladder cancer. The device uses a segmented robotic arm that can curve like a snake, allowing it to point in every direction. At the tip of the arm is a white light source, a fiberscope for observation, forceps for gripping and an optical fiber laser for cauterization. The flexibility of the arm allows surgeons to reach all areas of the bladder something not always possible with traditional bladder surgery, which may be why bladder cancer is persistent and requires repeated observation and surgery.
Valdastri is determined to replace colonoscopies with a procedure involving a miniature capsule robot and a magnetic transport system. He is the principal investigator on a new $1 million grant from the National Science Foundation funding the development of a Web-based modeling and simulation infrastructure that will speed up development of the robots. He hopes that sharing the online design environment with other researchers will provide early feedback, lower the cost of experimentation and create better designs of miniature medical devices through advanced tool support.
Goldfarb's research is supported by National Institute of Health awards R01HD059832 and R21HD068753. Webster's research is funded by NSF CAREER Award 1054331 and NIH awards 1R01EB017467 and R21EB011628; Simaan's research was supported by NSF CAREER Award 1063750 and NIH award R21EB015623; and Valdastri's research is supported by NSF grant 1239355.
Whether it's trailblazing diabetes wound healing or securely organizing medical records, engineers are developing solutions for improved health care, disease prevention, new medical techniques and medicines, effective health care administration, and exploration of the mysteries of the human body. These are a few of the projects currently underway.
How Does the Immune System
Know to Do That? It's amazing that humans know how an internal combustion engine works and how to send ships into space and back, but we don't know not really how human cells work. Associate Professor of Chemical and Biomolecular Engineering Matthew Lang is fascinated by the mechanics of the human body. He's using a new NIH R01 grant to study how mechanical force triggers activation of T cells, essential components of the body's adaptive immune response system.
T lymphocytes (T cells) have molecules called T cell receptors on their surfaces. The adaptive receptors are capable of recognizing foreign antigens on the surface of cells, signaling immune system activity to destroy the invader. Just how the TCRs recognize the antigens and signal has been a longstanding undefined biological mystery. Using cell antigen interactions mimicking natural events, Lang's team will determine the physical and chemical requirements for TCR triggering, and then probe the strength of the TCR molecular bond using antigens of different potency. The third stage will investigate how the mechanical force is converted into biochemical signals in live T cells.
By providing a deeper understanding of the adaptive immune response, Lang's work will help the development of drugs that fight foreign pathogens and tumors and that effect healing by modifying T cell activation.
Lang's research is supported by NIH grant AI19807 and 1RO1Al100643-01.
Harnessing Light for Cancer Patients
Cancer treatment is often invasive. People undergoing cancer treatment are poked, prodded, injected and radiated sometimes to the point of frustration. Assistant Professor of Biomedical Engineering Melissa Skala wants to change that. She's harnessing the power of light to develop tests that could improve the care of those with cancer.
Skala is working on imaging methods that will provide more information on the effects of drug therapy on tumors and patients. Skala has developed photothermal optical coherence tomography and two-photon microscopy techniques to extend the reach of imaging deep within tissue and capture microscopic changes in tumor cell and blood vessel function.
She and her team are working on preclinical models to quantify changes in molecular expression, metabolic rate and blood vessel function with tumor growth. As part of their research, they'll combine photothermal OCT methods with Doppler OCT imaging and two-photon microscopy. This novel, comprehensive approach will provide unique insight into the impact of cancer drug treatments on tumors. The data could tell if a therapy is working and how it affects tumor physiology, and may eventually be used for the design and development of individualized treatments for those with cancer.
This research is supported by NIH grants R00CA142888 and R21HL109748, Department of Defense grant BC121998, American Heart Association grant 12GRNT12060235, a grant from the Vanderbilt-Ingram Cancer Center Young Ambassadors Program and the Vanderbilt Breast Cancer SPORE.
Helping Wounds Heal
One of the most common complications of diabetes is chronic wounds, which approximately one in five patients with diabetes develop at some point. The best medication currently available for diabetic wounds works on less than half of patients. Nonhealing wounds can lead to severe consequences, even amputation of the affected foot or limb.
Craig Duvall , assistant professor of biomedical engineering, is investigating a new approach that would deliver small interfering ribonucleic acids (siRNA), a promising new class of drugs, to wounds in the skin and increase healing. His challenge is getting the siRNA into the cells where they can work, because siRNA molecules cannot easily pass into cells by themselves.
To solve the problem, Duvall has constructed a novel "smart" polymer nanoparticle that can package siRNA and efficiently deliver it into cells. The nanoparticles are, in turn, embedded into synthetic tissue scaffolds that biodegrade and slowly release them within the wound site. Duvall's team has gathered promising data that this approach can be used to promote formation of new blood vessels, a key step in the wound healing process.
This research is supported by NIH award R21EB012750 and NIH R01AR056138.