Evaluation of a novel flexible, lightweight blanket-like torso coil in pediatric MRI at 1.5-T - initial experience

Conventional phased-array torso coils used for abdominal MRI are relatively heavy and inflexible, potentially affecting patient comfort and technologist workflow.

To compare image quality, patient experience, and technologist experience using a recently United States Food and Drug Administration-cleared flexible, lightweight, blanket-like torso coil versus a conventional torso coil for pediatric abdominal MRI.

In this prospective institutional review board-approved study, 20 pediatric patients (7 years-old to 18 years-old) undergoing routine clinical outpatient abdominal MRI were imaged on the same 1.5-T system using both a conventional torso coil and a flexible blanket-like torso coil (Smart Fit TorsoCardiac; Philips Healthcare). After standard clinical imaging, selected sequences were repeated following coil exchange. Five pediatric radiologists independently evaluated paired image sets for subjective signal-to-noise ratio (SNR) and coil-related artifacts. Objective image quality was assessed using organ- and tissue-based SNR estimates and contrast-to-noise ratio (CNR) measurements. Patients and MRI technologists completed questionnaires regarding comfort, usability, and examination experience.

All 20 patients (median age, 15 years; 55% female) underwent imaging with both coils. Radiologists rated the novel coil as similar to the conventional coil for subjective SNR across all three sequences under study; coil-related artifacts were uncommon (2% of assessments for all sequences evaluated). Objective analysis showed no significant image-based SNR differences for most sequences, although the flexible coil demonstrated higher liver SNR on axial diffusion-weighted imaging (adjusted P=0.01). CNR did not differ between coils. Patients reported greater comfort and less anxiety with the flexible coil; 55% preferred it for future MRI examinations versus 20% for the conventional coil. Technologists also favored the flexible coil, with 70% expressing an overall preference.

The flexible blanket-like torso coil provided image quality similar to a conventional coil and was generally preferred by patients and MRI technologists.