Compressed mammograms by block subband coding. Medical assessment in the detection of microcalcifcations

Regions of Interest of analog Mammograms with and without Microcalcifications (95 Clinical Cases Randomly selected) were Digitized and then compressed by a factor 10:1 using a block subband coding technique. Detectability of Microcalcifications was compared before and after compression by a R.O.C (Receiver Operating Characterstic) Pocedure involving 7 graduated radiologists. No significant difference was found between the area under the two R.O.C. curves (z=0.658 p=0.05).