1324 AJR:193, November 2009 of PE include the following [2–5]. The first prospective evaluation of the diagnostic ac- curacy (sensitivity and specificity) of CT in a peer-reviewed article appeared in 1992 and was authored by Remy-Jardin et al. [6]. The first systematic review of the literature was made in 2000 by Rathbun et al. [7], who con- cluded that “use of CT in the diagnosis of PE has not been adequately evaluated; all stud- ies satisfied few criteria for methodological quality” [5]. The first report of the accura- cy of MDCT appeared in 2003 [8]. The first review of systematic literature reviews com- bined with a new systematic review of origi- nal studies was published in 2004 [5]. The first many-institutional evaluation did not ap- pear until 2006 with the publication of the data from the second Prospective Investiga- tion of Pulmonary Embolism Diagnosis (PI- OPED II), a study conducted at eight institu- tions by Stein et al. [9]. Given the emphasis of technology assessment researchers on the The Actual Role of CT and Ventilation – Perfusion Scanning in Workup for Suspected Pulmonary Embolism: Evidence From Hospitals Mythreyi Bhargavan 1,2 Jonathan H. Sunshine 1,3 Sheleika L. Hervey 4 Saurabh Jha 5 Joyce Vializ 1 Jean B. Owen 6 Bhargavan M, Sunshine JH, Hervey SL, Jha S, Vializ J, Owen JB 1 Research Department, American College of Radiology, 1891 Preston White Dr., Reston, VA 20191. Address correspondence to J. H. Sunshine (jsunshine@acr-arrs.org). 2 Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD. 3 Department of Diagnostic Radiology, Yale University, New Haven, CT. 4 Department of Radiology, West Virginia University, Robert C. Byrd Health Sciences Center, Morgantown, WV. 5 Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA. 6 Clinical Research Center, American College of Radiology, Philadelphia, PA. Health฀Care฀Policy฀and฀Quality฀•฀Original฀Research AJR 2009; 193:1324–1332 0361–803X/09/1935–1324 © American Roentgen Ray Society P ulmonary embolism (PE) is the third most common cause of car- diovascular death in the United States, with an estimated inci- dence of one case per 1,000 persons per year [1, 2]. Untreated major acute PE has a mortality rate of 26%, most of the deaths occurring in the first few hours after the embolism occurs [3]. Anticoagulation is the principal treatment but is associated with substantial risk of serious and occasionally fatal hemorrhagic complica- tions [4]. Therefore, accurate and prompt diag- nosis and prompt management of acute PE are essential. The signs and symptoms of PE are nonspecific, limiting the ability to make the di- agnosis without imaging. The favored noninva- sive imaging techniques for PE have changed over several decades [2]. In the most recent change, CT widely became the successor to nu- clear ventilation–perfusion (V/Q) scanning. Notable events in the history of assess- ment of the accuracy of CT in the diagnosis Keywords: CT angiography, chest CT, pulmonary embolism, technology adoption, ventilation– perfusion (V/Q) scanning DOI:10.2214/AJR.09.2677 Received February 27, 2009; accepted after revision April 28, 2009. This study was funded in part under a grant with the Pennsylvania Department of Health. The department specifically disclaims responsibility for any analyses, interpretations, or conclusions. This study is part of the American College of Radiology’s Diagnostic Patterns of Care research program. OBJECTIVE. Over the past two decades, CT has been found valuable in the diagnosis of pul- monary embolism (PE). We sought to ascertain the relative roles of CT and ventilation–perfusion (V/Q) scanning, the previously preferred technique, in the diagnosis of PE in recent practice and whether there is variation among hospital types. MATERIALS฀AND฀METHODS. Using the Medicare anonymized 5% of beneficia- ries complete claims file for 2005, we studied the use of relevant CT and V/Q scanning in the evaluation of patients with a diagnosis of PE and of patients with symptoms that might have been due to PE (chest pain, syncope, difficulty breathing). In 2008, we surveyed the radiology departments of Pennsylvania hospitals about the use of CT and V/Q scanning for PE, service availability hours, and what equipment was used. RESULTS. In all data, we found that CT was used approximately six times as frequently as V/Q scanning. In the Medicare data, only small differences in frequency of use of CT and V/Q scanning were associated with hospital characteristics. Academic hospitals did not dif- fer in a major way from other hospitals, nor did small or rural hospitals. In the survey, 97% of radiology departments reported that CT was available for evaluation of PE 24 hours a day 7 days a week. Ninety-three percent of departments reported V/Q scanning was available at some times; 77% reported V/Q available at all times. CONCLUSION. CT was a fully disseminated and dominant technique for the diagno- sis of PE by 2005, and it was readily available at small and rural hospitals. The lack of avail- ability of off-hours V/Q scanning at a substantial fraction of hospitals may be a problem for patients with contraindications to CT. Bhargavan et al. CT and V/Q Scanning of Pulmonary Embolism Health Care Policy and Quality Original Research Downloaded from www.ajronline.org by 52.73.204.196 on 05/13/22 from IP address 52.73.204.196. Copyright ARRS. For personal use only; all rights reserved