A mammogram uses X-rays to produce an image which helps specialists detect changes in breast tissue which could be breast cancer.

A more recent development, according to Hung Wai-ka, a general surgery specialist at Hong Kong Adventist Hospital, has been to use the technology of digital photography combined with X-rays to produce digital images rather than a film screen image.

Although more expensive that traditional mammography, which produces a printed image, digital mammography is gaining in popularity because the images are easy to store and because the specialist is able to manipulate the images to get a better look at the breast tissue.

"As doctors we are most interested in whether they give you more information and whether they more accurate in helping us detect cancer. With digital mammography the detection tool is the same, but we can do imaging processing to improve the visualization," says Hung.

A study in 2005 published in the New England Journal of Medicine by Dr Etta Pisano involving 50,000 women who had undergone both traditional and digital, found the overall accuracy was very similar in both the types of mammogram.

However, digital mammography was found to be superior in two groups of women: those younger than 50 years and those with dense breasts where cancer is less easy to pick up because of dense tissue.

"In these groups we found the digital mammogram is better because we can manipulate the image and that is very important," says Hung.

(HK Edition 10/20/2011 page4)