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By Karen Green, for NCSA -- Early and accurate diagnoses and evaluations of medical conditions can save lives, money, time, and a whole lot of stress on patients and their families. Yet diagnosis and evaluation often depend on circumstances that have nothing to do with a patient's medical condition. Circumstances such as where a patient lives and what medical specialists are available in that area suggest that a person's zip code can be a good indicator of the quality of his or her medical care. For example dysphagia, or a difficulty in swallowing, afflicts several hundred thousand people each year, including the elderly, premature babies, stroke and cancer patients, and people with neurological disorders. Undiagnosed, dysphagia can lead to respiratory problems, including life-threatening pneumonia caused by food or liquid in the lungs, and to malnutrition, which slows recovery from illness. Dysphagia can occur anywhere between the lips and the stomach. Oropharyngeal dysphagia, which results from mouth or throat problems, is generally diagnosed and treated by speech-language pathologists who have special expertise in this area. Despite a large number of oropharyngeal dysphagia patients, many rural and small community hospitals have no experts on staff qualified to diagnose the condition. Some states with large rural areas have no more than a handful of dysphagia experts, mostly concentrated in larger cities. Unequal care levels depend on whether or not you are lucky enough to have the right medical professionals nearby. Adrienne Perlman, a professor in the department of speech and hearing science at the University of Illinois at Urbana-Champaign, has studied, diagnosed, and treated dysphagia for 20 years. She recalls treating patients at a regional hospital in Iowa. "The patients would often travel three, even four hours to see me, sometimes by ambulance because they were so sick" says Perlman. "They would be exhausted by the time they'd see me. I remember thinking 'there's got to be a better way to do this.'" Perlman eventually came upon a possible solution to her diagnostic dilemma: evaluating patients with dysphagia through remote, real-time medical assessments conducted over broadband Internet connections. As part of the NCSA/UIUC Faculty Fellows Program, Perlman has spent the past two years developing a method for capturing and transmitting high-quality video data from the fluoroscopic examinations that are used to assess a patient's swallowing. Such a system, she hopes, will make real-time remote assessment of fluoroscopy exams a common practice. "We are testing the system with videofluoroscopic examinations of the oral and pharyngeal stages of the swallow in patients with dysphagia, but the system could be used for assessments in other areas of medicine," she says. "It is simply a system for interactive, real-time assessment of video images." Weerasak Witthawaskul, a doctoral student in computer science at the U of I and Perlman's research assistant, and NCSA staff assisted Perlman by creating a Java-based interface that allows a desktop computer in a hospital X-ray suite to communicate with a similar computer in Perlman's laboratory on the U of I campus. This system allows Perlman to control the hospital-based PC from her lab and provides an interface for examining high-resolution MPEG versions of the video fluoroscopic images taken at the hospital. "The process is completely controlled from the computer in our lab" explains Perlman. "All the technician at the hospital has to do is turn on the computer in the X-ray suite." Following the examination, Perlman is able to observe the swallow event at full speed, in slow motion, or frame by frame on her laboratory computer. Moreover, she has the expertise to analyze the test data more precisely than most hospital clinics or labs. While staff at most clinics or labs can look at fluoroscopic images and determine whether cartilage, bone, or other structures move during the swallowing process, Perlman can measure displacement -- how much and how long a structure moves and whether the movement is more or less pronounced than in previous exams. Displacement measurements can help determine both whether a dysphagia patient is recovering and the rate of recovery. Videofluoroscopy with remote assessment is a relatively simple process that involves two major components. The first is a server PC equipped with video encoder hardware, located in the hospital X-ray suite. For the prototype system developed by Perlman and Witthawaskul, a 300-MHz Pentium computer was located in the X-ray suite at Carle Hospital in Urbana, IL. A 700-MHz Pentium computer, called the control and analysis computer, was located in Perlman's lab, about a mile from the hospital. The two machines were connected via the hospital's T1 Internet connection at a maximum speed of 1.5 megabits per second. Perlman, the dysphagia expert, directed the fluoroscopy exam from her lab, communicating with the hospital radiologist and the patient via a simple speakerphone connection. To operate Perlman's system, the hospital's radiologist merely turns on the server computer, then conducts a routine fluoroscopy exam. No special expertise is needed. The examination takes place while the patient swallows a small amount of barium solution, which allows the fluoroscope to view the movement of the barium and of various structures in the mouth and throat. The fluoroscopic image is about as close as humans come to having X-ray vision. Skin and hair are transparent, while the skull and other bones, cartilage, and hollow tissues such as the esophagus and windpipe, are clearly visible. As the patient swallows, it is relatively easy to follow what happens. The hospital-based PC digitizes the videofluoroscopic images into an MPEG format and records the patient's swallowing activity in the highest resolution possible. Meanwhile, the video data are transmitted in real time to the control and analysis computer in Perlman's lab. According to Perlman, the image quality during real-time transmission is adequate for directing the procedure, but does not offer the level of detail that she prefers for diagnosis. Real-time transmissions' low resolution results from the relatively limited bandwidth between the hospital and the lab. During the examination, the control computer in Perlman's lab obtains and displays the video data in real-time with only a three- to five-second delay -- not enough to affect Perlman's ability to direct the procedure or cause undue radiation exposure to the patient. After the examination is completed, high-resolution fluoroscopic images, which were stored on the hospital computer during the examination, are transferred to Perlman's laboratory for complete analysis. Using these high resolution images, Perlman is then able to look at the data frame-by-frame, search the video for specific frames, and adjust the brightness and contrast to better examine the data. Perlman's system could bring great change to medical establishments. Nursing home patients, who often arrive exhausted after traveling long distances for fluoroscopy exams, could avoid tiring travel and the expense of an ambulance. People fighting other illnesses, or weakened from radiation treatments could receive expert medical assessments in their hometowns. Exams generally not offered at small and rural hospitals today -- from assessments of swallowing functions to endoscopy, which evaluates structures such as the larynx, the esophagus, and the colon -- could be easily available to patients who live hundreds or even thousands of miles from a major hospital. A person's zip code might no longer indicate the quality of medical care. Perlman has high hopes for the system and is continuing her work with NCSA to upgrade the computer interface, improve the quality of the video from MPEG-1 to MPEG-2, and design a sophisticated security system that guarantees patient confidentiality. Eventually Perlman hopes to create a dysphagia portal and databank that would give researchers, educators, and clinicians worldwide access to dysphagia data. She sees the portal developing as a virtual workspace for swallowing experts where they will be able to collaborate with colleagues, discuss unique cases, examine data from around the world, and follow specific cases for months or years. "What we've done so far is prove that this system can work," she says. "It is a service to the community and could be developed as a grid-based medical application." ----- Relevant URLs: --Access story: http://access.ncsa.uiuc.edu/Stories/dysphagia/ --NCSA Dysphagia Telemedicine Project: http://white.shs.uiuc.edu:8080/