%0 Journal Article
%@ 1438-8871
%I Gunther Eysenbach
%V 3
%N 2
%P e21
%T Virtual Sonography Through the Internet: Volume Compression Issues
%A Ferrer-Roca,Olga
%A Vilarchao-Cavia,Joseba
%A Troyano-Luque,Juan-Mario
%A Clavijo,Matilde
%+ University of La Laguna, 38071 Tenerife, Canary Islands, Spain, +34 922 319321, catai@teide.net
%K Virtual sonography, telemedicine, 3D-ultrasound, 3-D ultrasound, obstetrics, volume rendering
%D 2001
%7 22.6.2001
%9 Original Paper
%J J Med Internet Res
%G English
%X Background: Three-dimensional ultrasound images allow virtual sonography even at a distance. However, the size of final 3-D files limits their transmission through slow networks such as the Internet. Objective: To analyze compression techniques that transform ultrasound images into small 3-D volumes that can be transmitted through the Internet without loss of relevant medical information. Methods: Samples were selected from ultrasound examinations performed during, 1999-2000, in the Obstetrics and Gynecology Department at the University Hospital in La Laguna, Canary Islands, Spain. The conventional ultrasound video output was recorded at 25 fps (frames per second) on a PC, producing 100- to 120-MB files (for from 500 to 550 frames). Processing to obtain 3-D images progressively reduced file size. Results: The original frames passed through different compression stages: selecting the region of interest, rendering techniques, and compression for storage. Final 3-D volumes reached 1:25 compression rates (1.5- to 2-MB files). Those volumes need 7 to 8 minutes to be transmitted through the Internet at a mean data throughput of 6.6 Kbytes per second. At the receiving site, virtual sonography is possible using orthogonal projections or oblique cuts. Conclusions: Modern volume-rendering techniques allowed distant virtual sonography through the Internet. This is the result of their efficient data compression that maintains its attractiveness as a main criterion for distant diagnosis. 
%M 11720963
%R 10.2196/jmir.3.2.e21
%U http://www.jmir.org/2001/2/e21/
%U https://doi.org/10.2196/jmir.3.2.e21
%U http://www.ncbi.nlm.nih.gov/pubmed/11720963