Analog Devices' New Converter Boosts Slice Count in CT Scanners

A new data acquisition chip may lay the groundwork for faster, higher-quality computed tomography (CT) scanners.

Analog Devices' new ADAS1128 current-to-digital converter could serve as a key element in the drive to boost the number of slice counts in CT scanners, which in turn could help physicians more easily diagnose maladies ranging from cancer to cardiovascular disease to orthopedic injuries. The new converters would accomplish that by enabling scanner manufacturers to incorporate more of the detectors that are responsible for the slice counts.

"The trend is toward higher and higher slice counts," says Scott Pavlik, strategic marketing manager for imaging patient monitoring at ADI. "The reason is that if you have more slices, you have more area to capture the image."

ADI's converters help accomplish that by integrating a 24-bit analog-to-digital converter with 128 data acquisition channels - about four times as many as the norm for such devices. That allows scanner manufacturers to pack more detectors into a smaller area, which is significant because such machines typically use about 1,000 detectors per slice. As such, state-of-the-art, 320-slice-count machines use approximately 320,000 detectors.

"In these high-slice-count machines, one could image the heart in a single shot," Pavlik says. "And in addition to doing that, you could do animated views of the heart as it's beating."

The current-to-digital converters, which convert light photons to digital signals, could also help to make CT scanners faster and more affordable. The devices can  reportedly boost speed from 6 kilosamples per second (kSPS) to 20 kSPS and reduce system electronics by 50 percent compared to older designs, ADI says.

"It all translates to faster scan times," Pavlik says. "It will allow hospitals to diagnose patients more quickly in an emergency room or to increase the throughput of patients through a given machine."

Analog Devices