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A newly developed Adaptive Image Receive (AIR) coil is designed to be more flexible to conform to the human body habitus, and may improve image quality by reducing the distance between the coil element and the imaging subject. This study evaluated the AIR coil's usefulness for liver MR imaging at 3.0 T in comparison with that of a conventional coil retrospectively.The study population comprised 50 consecutive patients, who underwent follow-up liver MR examinations with a 3.0-T MR system using both an AIR coil and a conventional coil to evaluate hepatocellular carcinoma. Three-dimensional fat-suppressed T1-weighted gradient-echo images before and after injection of an MRI contrast agent, T2-weighted single-shot fast spin-echo (SSFSE) images, and diffusion-weighted (DW) images obtained with the AIR coil were compared with corresponding images obtained with the conventional coil. One radiologist measured signal-to-noise ratios (SNRs), while two other radiologists used a 3-point scale to independently assess subjective image noise, artifacts, signal uniformity, and overall image quality.SNRs for the AIR coil were significantly higher than those for the conventional coil (P .05). Subjective image noise for the AIR coil on pre- and postcontrast T1-weighted and DW images was lower than for the conventional coil for both readers (P .05). Overall image quality on pre- and postcontrast T1-weighted and DW images for the AIR coil was better than that for the conventional coil for at least one reader (P .05).In comparison with the conventional coil, AIR coil improved SNR and image quality of liver MR imaging.

To evaluate the image quality of CT urography (CTU) obtained with ultra-high-resolution CT (U-HRCT) reconstructed with hybrid iterative reconstruction (IR) and model-based IR algorithms.Forty-eight patients who underwent CTU using the U-HRCT system were enrolled in this retrospective study. Excretory phase images were reconstructed with three protocols: Protocol A: 1024-matrix, 0.25 mm-thickness, and model-based IR; Protocol B: 1024-matrix, 0.25 mm-thickness, and hybrid IR; Protocol C: 512-matrix, 0.5 mm-thickness, and model-based IR. Objective image noise and contrast-to-noise ratio (CNR) of the renal pelvis were compared among the protocols. Three-dimensional maximum intensity projection CTU images were generated from each image data set, and image quality was evaluated by two radiologists.Protocol C yielded the lowest objective image noise and highest CNR, whereas Protocol A had highest image noise and lowest CNR (P 0.01). Regarding the detailed delineation of urinary tract structures on the images, the mean visual score was significantly higher for Protocol A than for Protocols B and C (P 0.001), and the mean score for subjective image noise was significantly lower for Protocol A than for Protocols B and C (P 0.001).CTU with a 1024-matrix and model-based IR depicted the structures of the urinary system in the most detail.