Diagnosis of pulmonary embolism with use of computed tomographic angiography

Pulmonary embolism (PE) is a common diagnostic problem, particularly in hos pitalized patients. It remains a frequent cause of unexpected deaths. Tradi tionally, the diagnostic work-up for suspected PE has centered on the use o f ventilation-perfusion (V-P) radionuclide lung scanning. However, V-P scan ning does not provide adequate confirmation or exclusion of the diagnosis i n the majority of patients who undergo this test. Although published guidel ines advise further diagnostic testing after nondiagnostic V-P scans, clini cians infrequently perform such testing, and management decisions are commo nly based on clinical judgment. In recent years, there has been an increasi ng interest in the use of computed tomographic (CT) angiography in the diag nostic evaluation of patients with suspected PE, Although there are unresol ved issues regarding its sensitivity in detecting, small peripheral emboli, CT angiography is more accurate than V-P scanning in the diagnosis of PE a nd yields other intrathoracic diagnoses. Herein we summarize the problems w ith the traditional approach centered on the use of V-P scanning in the dia gnosis of PE and propose an alternative diagnostic strategy based primarily on the use of CT angiography.