Diagnostic accuracy in remote expert consultation using standard video-conference technology

An international multicenter study (Germany, Sweden, and Switzerland) was performed to investigate the feasibility and diagnostic reliability of standard video-conferencing (VC) technology for remote expert consultation in radiology. Three high-spatial-resolution films (hand-bone, mammography, chest) and two low-spatial-resolution image sets (liver CT and MRI) were studied (total 446 images taken from different examinations). The images were recorded by a video camera, transmitted via public broadband networks, and displayed on a video monitor. The resolution of the recorded images varied from 2.4 lp/mm to 4.8 lp/mm at maximum zoom. After 3-4 months, the images were reexamined using conventional light-box reading. Diagnostic reliability was evaluated by receiver operating characteristics (ROC) analysis. With video conferencing, there was a noticeable loss of diagnostic accuracy for the high-spatial-resolution films, whereas for liver CT and liver MRI images VC reading seemed to be satisfactory (average area value difference < 0.02).