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Evaluation of a Digital Camera for Acquiring Teleradiology Images Elizabeth A. Krupinski, PhD University of Arizona Department of Radiology Arizona Telemedicine Program Ronald S. Weinstein, MD University of Arizona Department of Pathology Arizona Telemedicine Program Carlos Gonzales, MD
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Evaluation of aDigital Camera for Acquiring Teleradiology Images
Elizabeth A. Krupinski, PhD University of Arizona Department of Radiology Arizona Telemedicine Program Ronald S. Weinstein, MD University of Arizona Department of Pathology Arizona Telemedicine Program Carlos Gonzales, MD Michael Gonzales Patagonia Family Health Center
This work was supported by:1) US Dept. Agriculture, Rural Utilities Service Distance Learning and Telemedicine Grant2) US Dept. Commerce, National Telecommunications and Information Administration TIIAP Grant3) Office of Rural Health Policy, HRSA Dept. Health & Human Services Rural Telemedicine Grant Program4) The State of Arizona
Goal • To determine if a commercially available digital camera can be used to acquire photographs of radiologic images to transmit them via store-forward technology over a telemedicine network.
ATP Telemedicine Sites Tuba City Ganado Kingman Flagstaff AHSC Hub Cottonwood Telemedicine Payson Springerville Telepathology DOC - Phoenix Teleradiology Whiteriver DOC - Yuma NARBHA Net AHSC Kino Tucson VA Patagonia Nogales Douglas
Arizona Rural Telemedicine Network (ARTN) • ATM based network based on high-speed T1 carriers • 3 ATM switches located in Northern (Flagstaff), Central (Phoenix) & Southern (Tucson) regions of the state • Tandberg CANVAS Health Care Unit for real-time interactive teleconsults • MedVision for store-forward teleconsults • CompuRAD/Lumisys for teleradiology
Teleradiology Network • 3 of the sites (Kino Community Hospital in Tucson, Springerville & White River) are connected to the University Medical Center via the high-speed (T1) Arizona Rural Telemedicine Network (ARTN) • 1 site (Tucson VA) uses dial-up service
Sub-Specialties Covered Cardiology Ophthalmology Peds. Orthopedics Dental Orthoped. Surg. Peds. Psychiatry Dermatology Orthopedics Peds. Pulmonology Endocrinology Otorhinology Peds. Rheumatology Fam. & Comm. Med. Pain Clinic Peds. Urology Gastroenterology Pathology Psychiatry Genetics Peds. Cardiology Radiology Hematology/Oncology Peds. Dermatology Reprod/Infertility Infectious Disease Peds. Endocrinology Rheumatology Internal Medicine Peds. Gastroenterology Surgery Medicine Peds. Hem/Onc Surgical Oncology Nephrology Peds. Infec. Disease Toxicology Neurology Peds. Nephrology Urology Ob/Gyn Peds. Neurology Vascular
Rationale • Teleradiology is an important part of an increasing number of Radiology & Telemedicine programs • Saves time and feedback to referring clinician is faster than with other methods (e.g., courier) - 85% of our teleradiology cases have a “wet read” report generated within 6 hours
Rationale • It can, however, be expensive! • For digital modalities a merge box is needed • For plain film a digitizer or video capture system is required • Some sites just cannot afford these options • A low-cost alternative had to be explored
Rationale • The Patagonia Family Health Center needs consults especially in orthopedics & bone radiology • Have no x-ray facilities so send patients to Nogales’ Mariposa Clinic, the report & films are sent over either with patients or later • Problem - Mariposa only has a general radiologist so sub-specialty consults are often required
The Camera Canon PowerShot600 CCD image sensor 832 x 608 pixels 24-bit color resolution f/2.5 lens Built-in flash 150 kB file size
The Cases • 40 bone trauma cases (e.g., fracture, subluxation, soft tissue damage) from the Patagonia Family Health Clinic • Cases that required a consult in the past & were representative of the types of cases they would be sending for teleconsults in the future - typically subtle lesions
The Photographs • Film images were placed on standard viewbox with extraneous light blocked out • The physician identified region(s) of interest based on clinical history and nature of problem • At least one global and one close up shot were acquired for each image using the Canon PowerShot camera
Display • Images sent over ARTN to the MedVision workstation • Color monitor, 1024 x 768 pixels • Window/level, zoom/pan available for use during viewing • Film images displayed on standard viewbox
Protocol • 2 orthopedic surgeons & 2 bone radiologists reviewed the 40 cases on film & using the digital photographs displayed on the monitor • Film reading 6 months after monitor reading • Reported: • Diagnosis • Decision confidence using 6-level scale • Image quality using 4-level scale
Results - Image Quality • C2 = 20.32, df = 9, p = 0.02 • 9 of the photo cases were rated poor 4 film cases were rated poor • Of the 9 photo cases, 4 (45%) were rated as poor because the region-of-interest was not captured sufficiently • Some views (film & photo) were not what the readers were used to - different technologists
Results - Diagnoses* Reader Agreement (Kappa) 1 0.89 2 0.92 3 0.94 4 0.88 * Truth was determined by 2 radiologists not participating in the study from the film images
Results - Confidence * How many categories film & monitor confidences differ by
Conclusions • A digital still camera can be used effectively to capture images of bone trauma radiographs for store-forward telemedicine consults • Well-framed close-up shots of the region-of-interest are essential • Good quality original films are essential
Other Applications? • Other non-screening applications where a specific suspicious region-of-interest can be identified for close-up photographs • Unless the lesion is fairly gross, the global shots are not adequate for consultation - close-up shots are required in the majority of cases