Impact of iterative reconstruction on image quality and radiation dose in multidetector CT of large body size adults

Objective

To compare image quality and radiation dose using Adaptive Statistical Iterative Reconstruction (ASiR) and Filtered Back Projection (FBP) in patients weighing ≥91?kg.

Methods

In this Institution Review Board-approved retrospective study, single-phase contrast-enhanced abdominopelvic CT examinations of 100 adults weighing ≥91?kg (mean body weight: 107.6?±?17.4?kg range: 91–181.9?kg) with (1) ASiR and (2) FBP were reviewed by two readers in a blinded fashion for subjective measures of image quality (using a subjective standardized numerical scale and objective noise) and for radiation exposure. Imaging parameters and radiation dose results of the two techniques were compared within weight and BMI sub-categories.

Results

All examinations were found to be of adequate quality. Both subjective (mean?=?1.4?±?0.5 vs. 1.6?±?0.6, P?P?P?Conclusion In obese individuals, abdominal CT images reconstructed using ASiR provide diagnostic images with reduced image noise at lower radiation dose.

Key Points

? CT images in obese adults are noisy, even with high radiation dose. ? Newer iterative reconstruction techniques have theoretical advantages in obese patients. ? Adaptive statistical iterative reconstruction should reduce image noise and radiation dose. ? This has been proven in abdominopelvic CT images of obese patients.