David M. Schuster MD, Presenter: Nothing to Disclose

Tracy L. Faber PhD, Abstract Co-Author: Nothing to Disclose

Jonathon Nye PhD, Abstract Co-Author: Nothing to Disclose

John R. Votaw PhD, Abstract Co-Author: Nothing to Disclose

Hyun S. Kim MD, Abstract Co-Author: Nothing to Disclose

Roger S. Williams MD, Abstract Co-Author: Nothing to Disclose

Kathryn Witkowski, Abstract Co-Author: Nothing to Disclose

Bruce Jonathan Barron MD, Abstract Co-Author: Stockholder, Immunomedics Inc

James Galt, Abstract Co-Author: Nothing to Disclose

Co-registration and simultaneous viewing of planar dynamic radiolabeled RBC scintigraphy with multiplanar CT is feasible by means of specially designed software. Interpretation of dynamic RBC scintigraphy in this manner has the potential to increase diagnostic confidence, especially in the precise anatomic localization of potential sources of GI bleeding.

Radiolabeled red blood cell (RBC) scintigraphy is a well established technique in the evaluation of gastrointestinal (GI) hemorrhage. Accurate localization of the origin of the hemorrhage is essential for patient care. Yet, localization, especially differentiation of large from small bowel origin, may be difficult due to anatomic variations. The aim of this study was to develop a method of improved localization of the bleeding site through registration of the dynamic scintigram to a separately acquired CT scan.

A specially designed IDL program was created to co-register dynamic planar scintigraphic images and coronal slices from a CT scan. 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 manually translate and rotate with respect to the CT and may be displayed as a dynamic planar projection, as a time-projected MIP (TMIP), or as a single frame. Color tables and transparency can be adjusted for both the nuclear study and the CT. In practice, the nuclear data was registered by overlay of blood pool structures easily visualized in the scintigram (such as the aorta) with corresponding anatomy in the coronal CT. The method was tested on 10 RBC dynamic scintigrams with accompanying low-dose abdominopelvic CT scans acquired on a GE Discovery 670 SPECT/CT system.    

All data was successfully processed by the software program. The images were scaled and registered allowing simultaneous viewing and fusion of the planar dynamic scintigraphy and the coronal CT with additional availability of axial and sagittal CT planes. Both normal activity and abnormal intraluminal activity characteristic for GI hemorrhage were visualized and overlaid to corresponding CT images.

Schuster, D, Faber, T, Nye, J, Votaw, J, Kim, H, Williams, R, Witkowski, K, Barron, B, Galt, J, Improved Localization of GI Bleeding: Software for Fusion and Viewing of Planar Dynamic Radiolabeled RBC Scintigraphy with Multiplanar CT.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12025487.html