Pulmonary Artery Diameter Measurement and Semiquantitative Visual Scoring with Q-SPECT-CT in Acute Pulmonary Embolism.

ABSTRACT

OBJECTIVE: To investigate whether pulmonary artery diameters obtained from lung perfusion single-photon emission computed tomography-computed tomography (SPECT-CT) images and semiquantitative visual scoring (SVS) could serve as predictors of chronic pulmonary thromboembolic disease (CPTED) in acute pulmonary embolism patients (APE). STUDY DESIGN: Observational study. Place and Duration of the Study Department of Nuclear Medicine, Samsun Provincial Health Directorate, Gazi State Hospital, Samsun, Turkey, from January 2016 to March 2021. METHODOLOGY: A total of 142 patients undergoing lung perfusion SPECT-CT were included in this study. Patients were classified as APE (+) (n=42) and APE (-) (n=100) based on laboratory and radiological findings, clinical diagnosis, and treatment protocol. Non-contrast CT images were used to determine the diameters (mm) of the main (MPA), right (RPA), and left (LPA) pulmonary arteries and the main pulmonary artery/aorta (PA/AO) ratio. All perfusion defects were scored using SVS for the PE (+) group. Seventeen patients with a diagnosis of CPTED were followed up. The scores and arterial diameters of recovered APE and follow-up patients were compared. RESULTS: The mean diameters (mm) of MPA, RPA, and LPA and PA/AO ratio were 29.74±5.51, 21.73±4.11, 22.74±4.16, and 0.83±0.16 in the APE (+) group and 26.18±4.99, 19.35±3.84, 19.49±4.15, and 0.77±0.15 in the APE (-) group, respectively (p<0.001). Mean MPA diameter (mm), total defect (TD), right visual defect (RVD), and PA/AO ratio were 31.67±15.65, 29.88±15.59, 17.65±10.51, and 0.91±0.18 in the CPTED group and 28.06±4.59, 18.92±13.30, 10.4±7.41, and 0.78±0.15 in the recovered APE group, respectively (p<0.05). CONCLUSION: Assessment of pulmonary artery diameter and PA/AO ratio may indicate APE, but TD and RVD scores may be predictive factors for CPTED when included in the assessment along with MPA dilatation and PA/AO ratio. KEY WORDS Acute pulmonary embolism, Pulmonary artery diameter, Lung SPECT-CT, Chronic pulmonary thromboembolic disease, Semi-quantitative visual scoring.