In one promising approach, Jimmy Roehrig, R2 Technology's chief scientific officer, told Spectrum that his company has developed a way to map the characteristics of GE's detector to those of digitized film, in this way making the one equivalent to the other for the purposes of the detection algorithms. This strategy avoids a more fundamental change to the software, such as retraining the neural network. To date, the company has built software to normalize three digital detectors to match the characteristics of digitized film. For instance, physicians frequently use ultrasound to help determine whether a lesion detected on a mammogram is a malignant mass or a harmless cyst. Despite the diagnostic support they offer, each of these technologies has its limitations.
Technical fixes are in the works, nonetheless.
In ultrasound, for example, ATL Ultrasound of Bothell, Wash., an affiliate of Philips Medical Systems North America, in Shelton, Conn., has found a way to eliminate speckle and improve image contrast in general by reflecting sound off tissue from multiple angles. The device directs the ultrasound beam at nine angles sequentially, then reconstructs the image from all those viewpoints in real time. Since imaging principally relies on the physical characteristics of a cancer, such as its relative opacity to different wavelengths of light, it alone may not have all the answers. But if an imaging technique is combined with knowledge of the biological and biochemical nature of cancer, both sensitivity and specificity might be improved. Fla. The firm makes a breast imager that uses an optical wavelength laser instead of an X-ray source and computes the image from scattered, rather than transmitted, photons.