Software that merges radiologic images from red blood cell (RBC) scintigraphy with CT scan images in order for physicians to better localize the origin of a gastrointestinal (GI) bleed.
- Allows more accurate localization of GI bleeds than RBC scintigraphy alone.
- Fusion of two images can increase diagnostic confidence, especially in precise anatomic localization of potential sources of GI bleeding.
Approximately 400,000 upper and lower GI bleeds occur in the US annually. Esophagogastroduodenoscopy is the first choice for diagnosing upper GI bleeds and colonoscopy and angiography are commonly used tools for diagnosing lower GI bleeds, but the bleeding may not be clearly identified or the bleeding itself can impede visualization during these procedures. Although angiography provides information about the location of the bleed, it requires risky procedures including the use of intravenous contrast and catheterization and it is 10 times less sensitive than an RBC scintigraphy scan. RBC scintigraphy is often used to better localize the source of the bleeding and is commonly performed before angiography to better optimize screening for invasive techniques such as angiography. However localization of a bleed using scintigram imaging, particularly differentiation of large from small bowel origin, can be difficult due to anatomic variations.
Emory researchers have developed software that allows manual combination of images from a RBC dynamic planar scintigraphy and a separately acquired CT scan into a single image. By using the radiolabeled blood pool and corresponding anatomy as landmarks, the two images can be easily overlaid for an improved analysis. The software displays the dynamic scintigram, an overlay of the scintigram with the coronal CT, as well as sagittal and coronal CT slices with triangulation between the three CT orientations. The scintigram can be translated and rotated manually with respect to the CT and it may be displayed as a dynamic planar projection, as a time-projected maximum intensity projection, or as a single frame. In addition, color tables and image transparency can be adjusted for both images. This software has been successfully tested on ten RBC dynamic scintigrams and their accompanying abdominopelvic CT scans.
Software has been developed and tested with 10 subjects.