Wide Display Monitors Decrease Dose in Angiography

Wide display monitor to view angiography images lowers radiation exposure to patients and care providers during single-plane procedures, according to a study published in the American Journal of Roentgenology.

The author, from The Johns Hopkins Hospital, in Baltimore, MD, tested two monitor configurations, equipped with a single 56-inch (142-cm) configurable monitor and 30 × 40 inch (76 × 102 cm) flat-panel detectors, standard and wide display settings, to view a standard abdominal and pelvic phantom in a biplane angiography suite.

The author used a 10-second fixed subtracted radiographic sequence with a variable frame rate setting: four seconds at two frames and six seconds at one frame for a total of 14 images per acquisition.

The imaging sequence was repeated at a variety of different zoom levels:

• Zoom 0, 48 cm

• Zoom 1, 42 cm

• Zoom 2, 32 cm

• Zoom 3, 22 cm

• Zoom 4, 16 cm

• Zoom 5, 11 cm

The results showed that radiation significantly increased each time magnification was increased, but when the images were displayed in wide format, they could be viewed with a lower zoom level and lower radiation dose. “An increase in magnification from zoom 1 to zoom 5 yielded an increase in reference point air Kerma of approximately 520 percent without collimation and 425 percent with collimation,” the author wrote.

Low magnification allows for lower radiation dose during imaging, but viewing at low magnification isn’t practical with standard sized screens, the author noted. By using a larger screen, using lower magnification is possible.