Planar ventilation/perfusion (V/Q) scintigraphy is currently the standard method for the diagnosis of pulmonary embolism (PE) in most nuclear medicine centers. However, recent studies have shown a superior sensitivity and specificity when applying V/Q single photon emission computed tomography (SPECT) in diagnosing PE. This study evaluated the diagnostic performance of three-dimensional V/Q SPECT in comparison with planar V/Q scintigraphy.
Consecutive patients suspected of acute PE from June 2006 to February 2008 were referred to the Department of Nuclear Medicine at Frederiksberg Hospital, Denmark to a V/Q SPECT, as the first-line imaging procedure. Patients with positive D-dimer (>0.5 mg/l) or after clinical assessment with a Wells score of more than 2 were included and had a V/Q SPECT, low-dose CT, planar V/Q scintigraphy, and pulmonary multidetector computer tomography angiography performed the same day. Ventilation studies were performed using 81mKr. Patient follow-up was at least 6 months.
A total of 36 patient studies were available for analysis, of which 11 (31%) had PE. V/Q SPECT had a sensitivity of 100% and a specificity of 87%. Planar V/Q scintigraphy had a sensitivity of 64% and a specificity of 72%.
We conclude that V/Q SPECT has a superior diagnostic performance compared with planar V/Q scintigraphy and should be preferred when diagnosing PE.
Departments of aClinical Physiology, Nuclear Medicine and PET
bRadiology, Rigshospitalet, Copenhagen University Hospital
cCluster for Molecular Imaging, Faculty of Health Sciences, University of Copenhagen
dDepartment of Clinical Physiology and Nuclear Medicine, Frederiksberg Hospital, Denmark
Correspondence to Dr Henrik Gutte, MD, Department of Clinical Physiology, Nuclear Medicine and PET, 4011, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Copenhagen 2100, Denmark
Tel: +45 3545 4011; fax: +45 3545 4015; e-mail: email@example.com
Received 14 August 2009 Revised 21 September 2009 Accepted 21 September 2009