Radiation dose reduction in abdominopelvic CT using BMI specific low kV protocol

To evaluate the impact of a body mass index (BMI)-adjusted low kV protocol on radiation dose reduction and image quality in contrast-enhanced computed tomography (CECT) scans of abdomen and pelvis. Among the patients referred for CECT abdomen and pelvis scans, 120 were scanned using the standard protocol at 120 kV, whereas 96 were scanned using a BMI-specific low-radiation dose protocol. Patients were categorized into 3 BMI groups, low BMI (<18.5 kg/m 2 ) scanned at 80 kV, and normal BMI (18.5–24.9 kg/m 2 ) and high BMI (25–29.9 kg/m 2 ) at 100 kV. Effective dose ( E ) was recorded for each group. Image quality was assessed in the arterial and portal venous series. Quantitative image quality analysis was performed to estimate the signal-to-noise ratio (SNR), contrast to noise ratio (CNR), contrast enhancement index (CEI) and image noise. Qualitative analysis was independently assessed using a 5-point scale. The study reported higher radiation doses with higher BMI, however, low dose protocol achieved significant reduction in radiation dose across all BMI groups: low BMI, (21± 2) vs ( 10 ± 1.7) mSv ( P < 0.05); normal BMI, (22 ± 2.3) vs (14 ± 1.3) mSv ( P < 0.05); high BMI, (25 ± 2.8) vs (17 ± 1.8) mSv ( P < 0.05), for the standard and low dose protocols, respectively. Low dose protocols reported to have a higher image noise and CEI, lower SNR and comparable CNR across BMI groups in both arterial and portal venous series. Qualitative scores remain within acceptable diagnostic limits across BMI groups. BMI-specific low-kV CT protocols significantly reduced the radiation dose across all BMI categories while maintaining acceptable diagnostic image quality, suggesting that tailored low dose scanning may be feasible for clinical use.