Kenneth Muir, Presenter: Nothing to Disclose

Nicholas Christopher Donald Morley MA, FRCR, Abstract Co-Author: Nothing to Disclose

Edwin J R Van Beek MD, PhD, Abstract Co-Author: Research support, Toshiba Corporation Research support, Siemens AG Founder and owner, QCTIS, Inc Speaker, Toshiba Corporation

John Murchison MBCHB, Abstract Co-Author: Nothing to Disclose

To measure the rate of referral for radiological investigation of suspected acute Pulmonary Embolism (PE) and the incidence of PE detected in these scans, in a large teaching hospital. To observe changes in these measurements over the recent decade.

Retrospective review of radiology records for Computed Tomography Pulmonary Angiograms (CTPA) and Perfusion Scans (Q-scans) for suspected acute PE, between 1st April 2002 and 1st April 2012. Graphical and statistical analyses were performed with Microsoft Excel and Graphpad Prism. Some of the data for the earlier years in this study was published previously (O'Neill et al., 2004). Our local research ethics service approved this project.

111% increase in total VTE investigations over 10 years, from 996 to 2111. Substantial increase in referral for CTPA, incrementaly from 706 to 2020 scans per year. We also saw a decline in Q-scans from 290 to 91 per year. Increase in total number of PEs diagnosed, with annual incidence rising from 147 (15% positive-scan rate) to 426 (20% positive-scan rate), an increase of 190%. We observed an older population of PE patients, with mean age at diagnosis of PE going up from 62.2 to 65.4 (p= 0.03) and a 6-fold increase in PEs diagnosed in the 85-94 age group, from 9 to 57 per year.

There has been a major increase in the total number of investigations for suspected acute PE, accounted for by an increased use of CTPA with a corresponding decrease in the use of Q scans. In spite of what is generally assumed, the positive diagnosis rate increased, which may be a reflection of changed patient demographics combined with greater sensitivity of CTPA with newer CT scanners.

The current rate of investigation for suspected acute PE is justified by a high rate of relevant diagnoses. Analysis of PE severity in these cohorts is warranted and is ongoing.

Muir, K, Morley, N, Van Beek, E, Murchison, J, Increased Referral-rate for Investigation, and Increased Incidence of Symptomatic Radiologically-diagnosed Pulmonary Embolus in a Large Teaching Hospital, over a 10 Year Period.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13020408.html