Effects of Test-Bolus and Low-Dose Scan On Ct Pulmonary Angiography Image Quality In Patients with Different Body Mass Indexes.

Abstract

This study aimed to investigate different methods of obtaining high-quality Computed Tomography pulmonary angiography (CTPA) images using low-dose scanning in patients with different body mass index (BMI) values. Sixty patients with suspected pulmonary embolism were grouped based on their BMI values (BMI < 25, designated N, and BMI ≥ 25, designated O) and were assigned to receive either test bolus (TB) or bolus tracking (BT) at conventional (C) or low (L) dose. The effective dose (ED) in the N-TB-L group was lower than in the group N-TB-C (0.56\xa0±\xa00.05 vs. 3.78\xa0±\xa01.16, p\xa0<\xa00.001), with similar image quality (4.90\xa0±\xa00.31 vs. 4.70\xa0±\xa00.47, p\xa0=\xa00.120). The ED in the O-TB-L group was lower than in the O-TB-C group (0.54\xa0±\xa00.03 vs. 5.14\xa0±\xa01.34, p\xa0<\xa00.001), but the group O-TB-C s image quality was higher (4.65\xa0±\xa00.59 vs. 3.95\xa0±\xa00.89, p\xa0=\xa00.006). Groups N-TB-L versus O-TB-L, groups N-TB-L versus N-BT-L and groups O-TB-C versus O-BT-C had similar EDs (all ps\xa0>\xa00.05), but the image quality was different (all ps\xa0<\xa00.05). In conclusion, the results showed that the image quality of low-dose CTPA scanning using TB was similar to that of the conventional-dose CTPA in patients with BMI <\u200925 but was lower in patients with BMI ≥ 25. TB was better than BT for all patients, regardless of BMI, when receiving the same ED.