Volume 5, Number 3     May/June 1997

  Telemedicine

Telemedicine Technologies Across NASA

RGANIZATIONS ACROSS NASA are investigating ways to bring telecommunications information technologies and medicine together to deliver health care not only to the astronauts but to the citizens of Earth who live in locations that are remote and have limited access to medical care.

Examples of these activities follow. Visit the NASA Telemedicine Home Page at http://www.it.hq.nasa.gov/~kmorgan/telemed_blue/centers/centers.html or the NASA Telemedicine Technology Gateway at http://www.nttc.edufor a more comprehensive list that includes links to project sites.

Virtual Reality/Robotics
Ames Research Center (ARC) and Stanford University Medical Center are developing a virtual environment workbench to plan complex craniofacial reconstructive surgery. The team is designing grid generation methods and computer software to combine laser scans with computer tomography and magnetic resonance imaging to make three-dimensional constructions of the face and head.

Dr. Kevin Montgomery of Ames works the virtual environment boom. The glove on Montgomery's right hand allows him to manipulate the 3-D image on the monitor. Eventually, the glove will enable surgeons to "use" surgical instruments to practice surgery on the image.

The surgeon plans reconstruction in this virtual environment by exposing the skull beneath the face to remove bone, cut it into appropriate sections and replace them. Soft tissues are replaced computationally, and facial features are remolded automatically to the new skull. Once the surgeon is satisfied, he or she uses the workbench to prepare for actual surgery.

The workbench also could be used to train craniofacial surgeons. More than 50 steps with specific tools must be followed in exact sequence. Trainees would sit before a computer screen and practice these steps before ever touching a patient.

The workbench will be interactive. It will be capable of such interactions over long distances using high-speed networks and the Internet.

Marshall Space Flight Center's (MSFC) Virtual Reality Applications Program and EXOS Inc. of Massachusetts, now a Microsoft company, collaborated on a Sensing and Force-Reflection Exoskeleton (SAFiRE). SAFiRE senses hand and finger motion as human operator input and provides force-reflective feedback to the operator for both telerobotic and virtual environment applications. EXOS Inc., under a NASA Phase II Small Business Innovation Research (SBIR) project, produced an exoskeleton worn on the hand and forearm that senses motion and applies forces to the thumb, index finger and wrist. The SAFiRE project's technology base could be used to develop a biomechanically sound resistance exercise system with a passive motion option for the hand and wrist.

ARC and Stanford University, through the Neurosurgical Computational Medicine Testbed, are developing a neurocontroller, which is a robotic probe that "learns" the physical characteristics of the brain, giving surgeons finer control of surgical instruments during delicate brain operations. The robotic probe learns the brain's characteristics by using neural net software, the same type of technology that helps focus camcorders. The probe, equipped with a tiny pressure sensor, will enter the brain, gently locating the edges of tumors while preventing damage to critical arteries.

	The Neurosurgical Computational Medicine Testbed is a simple robotic device that may be used someday in human brain surgery.

The robotic probes are much smaller than standard probes and should further reduce potential brain damage. The smart computer program, which continues to learn as it gains more experience, controls speed and maximum pressure during the robotic neural net procedure. If the probe hits an artery, it will stop before it penetrates so the surgeon can decide what to do next.

ARC is developing robotic telepresence surgery to address medical emergencies that may occur during long-duration human space flights. A surgeon on Earth could control the surgery by issuing high-level commands to the robot.

Remote Diagnosis
ARC and the University of Maryland School of Medicine are examining the cognitive demands of differing types and experience levels of patient care providers in the Remote Diagnosis for Trauma Patient Resuscitation study.

Variables manipulated in the initial study involved the amount and type of information presented to the remote decision maker, including real-time vital sign overlay and case history description level. The study has assembled a library of videotapes of actual shock-trauma cases. The cases selected for study differ in problem type, diagnosis ambiguity, off-camera events and error recovery. Initial data collection shows certain types of patient condition judgments are difficult to assess (such as the extent of injury), and many important cues are missed because of the video medium. Diagnostic strategies include using correlated information to compensate for the lack of complete data and relying on secondary cues reflected in team activities. The results to date indicate the importance of rich case history descriptions and the difficulty of maintaining a dynamic patient model, perhaps from not being in the control loop.

Military, disaster aid, search-and-rescue teams and doctors with rural patients could use ARC's Automation and Support System for Expert Telescience (ASSET), a real-time intelligent advisor that makes quick decisions on the significance of incoming data, to diagnose and treat patients in remote locations. ASSET was developed to improve the real-time engineering/scientific return of measurements/experiments by providing the software operator with an "intelligent assistant" that encapsulates much of the relevant knowledge mastered by the project expert. ASSET's several modules together collect, calibrate and quality monitor data, diagnose data-collection problems, monitor and formulate hypotheses, determine and schedule session steps and provide general-purpose help to the operator. These modules could be used together or separately for a specific application.

Image Compression and Enhancement
High Performance Data Compression (HPDC) developed by Goddard Space Flight Center will reduce images to a fraction of their original size by a 10:1, 20:1 or even higher compression ratio. Decompressed data have some distortion, yet this technique offers the quick-look capability from a large format sensor and allows scientists to perform telescience by selecting areas of interest for further detailed observation. HPDC analysis and simulation results defined an algorithm that offers better image quality than the industry-standard JPEG compression scheme. HPDC can process a more dynamic and wider range of data than JPEG, and its implementation and operation are much simpler. HPDC uses already-developed lossless compression hardware.

This photograph compares the application of Retinex image processing (right) to conventional processing (center) of a medical x-ray image (left).

ARC developed Super-Resolved Image Processing Software (S-RIPS) to improve the quality of images from space probes, but the technology could be applied to telemedicine conferences and medical imaging. S-RIPS creates a super-resolved image, with both spatial and grayscale resolution improved, by using a number of source images of the same object from slightly different perspectives. As the number of digitized source images increase, the software produces even finer resolution images.

Retinex image enhancement methods were developed for color but also are useful for black-and-white medical images, such as x-rays and MRIs. This photo shows an original MRI of a cervical spine at c6 vertebra (left) and the Retinex-processed image (right).

Retinex image enhancement methods developed at Langley Research Center, which are being commercialized for color, provide a graceful compression of visual information. This compression also is useful for black-and-white medical images, such as x-rays and MRIs.

Often, medically important visual phenomena are spread across a widely varying background exposure, obscuring clear visualization. The Retinex method restores all the visual information for a more accurate diagnostic interpretation. This method can be applied remotely on digital images and transmitted to any network location for a rapid examination by the appropriate specialist. The method also may be applied locally by a specialist, and the enhanced, interpreted images may be transmitted back to the physician or the originating laboratory.

Education
MSFC's Virtual Reality Applications Program is developing, evaluating and using an inexpensive virtual reality human cadaver software application for classroom anatomy instruction. The software will run on a Pentium-based personal computer. The detailed model will include subdivided organs, texture mapping and three-dimensional sound for the major organs. This immersive learning environment is expected to afford quicker recognition, orientation and retention in human anatomic instruction. This project could lead to other virtual reality science training applications.

ARC and MusculoGraphics, Inc., through the Advanced Research Projects Agency, are working on Surgical Simulation for Limb Trauma Management, an effort that will enable military surgeons to learn surgical procedures on realistic computer models, which will improve training for surgical trauma care. Recent computer software developments have enabled conventional two-dimensional medical imagery to be converted into detailed three-dimensional human anatomy representations. The team is creating three-dimensional computer limbs using this software. These realistic anatomical models can be manipulated to simulate specific wounds and wound treatments, allowing surgeons-in-training to gain "virtual" experience in a wide range of trauma scenarios.

The technology also can be used for collaborative telemedicine by transmitting three-dimensional images to experts in other locations. When connected to telemetry lines, the system can transmit anatomically accurate images to experts in rear-echelon hospitals, enabling medics to interact with experienced physicians.

ARC's Center for Health Applications of Aerospace Related Technologies (CHAART) expands the use of aerospace-related technologies for global health monitoring by the human health community through training, education, application projects and the direct transfer of proven technologies and knowledge to research/control agencies and universities. Many of the parameters associated with environmental change and disease patterns can be sensed remotely by instruments aboard aircraft and satellites and modeled spatially with specialized computer software. Remote-sensing and geographic information system technologies can be used to pinpoint disease prevalence and patterns and a disease's occurrence in space and time.

Internet
The Jet Propulsion Laboratory and the Los Angeles County Center for the Vulnerable Child developed a Web-based system that enables fast turnaround on child abuse cases. The Virtual Center for the Vulnerable Child enables Internet-connected schools to use digital cameras to report suspected child abuse cases to a group of child abuse experts. Specially equipped remote clinics use telemedicine equipment, such as a videoconferencing system combined with a special dermatology scope, to perform exams in real time should further inspection be required.

	Dr. Terry Lightner in Harlingen, Texas, transmits a child's heart beating to doctors at the University of Texas Health Science Center at San Antonio, 250 miles away. South Texas lacks medical specialists in a number of areas, including cancer treatment.

The Aerospace Medicine Division at NASA Headquarters has teamed with the University of Pittsburgh to develop the Global Health Network (GHNet) using the World Wide Web. This worldwide network provides access to a plethora of data and information on a variety of medical and global health issues. GHNet also serves as a virtual university, providing interactive collaborations and communications to support medical education.

The Aerospace Medicine Division at NASA Headquarters and the Pan American Health Organization have established an Internet-based disaster preparedness network, linking health sector disaster preparedness offices in several Central American and South American countries with appropriate agencies within those countries and the region to strengthen disaster management, preparedness and response. This activity uses the Internet as a cost-effective tool for supporting the training of disaster response personnel in the host country.

Dryden Flight Research Center, Johnson Space Center, the University of Texas Health Sciences Center, Sprint and VTel launched a HOST-consortium project to bring advances in telemedicine to cancer-stricken children in medically underserved south Texas. HOST is a consortium composed of key players in the health care information systems industry. NASA helped provide two-way audio/video linkages so physicians in San Antonio could examine patients, review lab tests and consult primary care physicians at South Texas Hospital in Harlingen. South Texas lacks medical specialists in a number of areas, including cancer treatment, putting children in the region at a disadvantage. Prior to NASAÕs involvement, children in the area had to travel more than 250 miles to a San Antonio hospital to receive cancer treatments or wait for the one day a month that a specialist could visit their local hospital.

For more information about contacts for a specific project,
contact Shaik Mazharullah at the National Technology Transfer Center. Call 800/678-6882.
Please mention you read about it in Innovation.