Peggy Shih-Pei Wu MD, Presenter: Nothing to Disclose

Annette Ingram Joe MD, Abstract Co-Author: Nothing to Disclose

Michyla L Bowerson MD, Abstract Co-Author: Nothing to Disclose

Chintana P. Paramagul MD, Abstract Co-Author: Nothing to Disclose

Mark Alan Helvie MD, Abstract Co-Author: Institutional grant, General Electric Company Consultant, General Electric Company

Marilyn A. Roubidoux MD, Abstract Co-Author: Nothing to Disclose

The Indian Health Service (IHS) implemented screening digital mammography on Mobile Women's Health Unit (MWHU) to serve Northern Plains reservations. Via satellite, Univ. of Michigan radiologists remotely interpreted IHS mammograms. Because most IHS telemammography patients were new to Univ. of Michigan, prior mammograms were not usually immediately available while priors were almost always available for local patients. We investigated radiologists’ call back and prior mammogram requests patterns, and outcome of obtaining priors in telemammography.

We retrospectively reviewed BIRADS 0 reports of 2007-2009, among 14 radiologists and 2640 IHS patients after IRB approval. Reasons for prior requests and outcomes were assessed. IHS call back and prior request rates were compared to local screening data of same time period. Some IHS call backs were done on MWHU if it had not left screening locations, but most were done later at facilities up to 180 miles away.

Of 2640 IHS reports, 572 (21.7%) = BIRADS 0, 388 (14.7%) of which were prior requests; in comparison, our local prior request rate = 3.8%. Common reasons for prior requests were: asymmetry (24.0%), calcifications (15.0%), mass +/- calcifications (12.9%), no reason stated (32.5%). 322/388 (83.0%) of requested priors were obtained, of which, 48 (14.9%) were called back and 2 (0.62%) were malignant. Of 66 cases when priors were not obtained, 21/66 (31.8%) were called back. Individual radiologist IHS mean prior request rate = 18.9%, (6.65% - 37.5%, Std Dev 9.25%). Total IHS call backs (initial call backs + call backs after comparing priors) = 277 (10.5%), similar to local call back rate = 9.9%. Individual radiologist IHS mean call back rate = 11.2%, (5.00% - 15.2%, Std Dev 2.57%).  

Large proportion of BIRADS 0 occurs in telemammography due to unavailable prior mammograms. Obtaining priors resulted in fewer callbacks with cancer detection rate consistent with screening population. Obtaining priors was especially useful in IHS population because call back imaging is difficult. IHS call back rates were similar to local practice. Much more radiologist variability exists in practice of requesting priors than call backs.

Large proportion of BIRADS 0 occurs in telemammography due to unavailable comparison mammogram and obtaining priors resulted in need for  fewer call backs.

Wu, P, Joe, A, Bowerson, M, Paramagul, C, Helvie, M, Roubidoux, M, Telemammography for the Indian Health Service: Prior Mammogram and Call-back Request Patterns.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11007365.html