Noncontrast Perfusion Single-Photon Emission CT/CT Scanning A New Test for the Expedited, High-Accuracy Diagnosis of Acute Pulmonary Embolism

作者：Lu Yang; Lorenzoni Alice; Fox Josef J; Rademaker Juergen; Vander Els Nicholas; Grewal Ravinder K; Strauss H William; Schoeder Heiko

来源：Chest, 2014, 145(5): 1079-1088.

DOI：10.1378/chest.13-2090

Background: Standard ventilation and perfusion (V/Q) scintigraphy uses planar images for the diagnosis of pulmonary embolism (PE). To evaluate whether tomographic imaging improves the diagnostic accuracy of the procedure, we compared noncontrast perfusion single-photon emission CT (Q-SPECT)/CT scans with planar V/Q scans in patients at high risk for PE.
Methods: Between 2006 and 2010, most patients referred for diagnosis of PE underwent both Q-SPECT/CT scan and planar V/Q scintigraphy. All scans were reviewed retrospectively by four observers; planar scans were read with modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and Prospective Investigative Study of Pulmonary Embolism Diagnosis (PISA-PED) criteria. On Q-SPECT/CT scan, any wedge-shaped peripheral perfusion defect occupying. 50% of a segment without corresponding pulmonary parenchymal or pleural disease was considered to show PE. The final diagnosis was established with a composite reference standard that included ECG, ultrasound of lower-extremity veins, D-dimer levels, CT pulmonary angiography (when available), and clinical follow-up for at least 3 months.
Results: One hundred six patients with cancer and mean Wells score of 4.4 had sufficient follow-up; 22 patients were given a final diagnosis of PE, and 84 patients were given a final diagnosis of no PE. According to PIOPED II, 13 studies were graded as intermediate probability. Sensitivity and specificity for PE were 50% and 98%, respectively, based on PIOPED II criteria; 86% and 93%, respectively, based on PISA-PED criteria; and 91% and 94%, respectively, based on Q-SPECT/CT scan. Seventy-six patients had additional relevant findings on the CT image of the Q-SPECT/CT scan.
Conclusions: Noncontrast Q-SPECT/CT imaging has a higher accuracy than planar V/Q imaging based on PIOPED II criteria in patients with cancer and a high risk for PE.

• 出版日期2014-5