Contrast-Enhanced T1-Weighted Head and Neck MRI: Prospective Intraindividual Image Quality Comparison of Spiral GRE, Cartesian GRE, and Cartesian TSE Sequences

Background: Sequences with non-Cartesian k-space sampling may improve image quality of head and neck MRI. Objective: To compare intraindividually the image quality of a spiral gradient recalled echo (GRE) sequence and conventional Cartesian GRE and Cartesian turbo spin echo (TSE) sequences for contrast-enhanced T1W head and neck MRI. Methods: This prospective study included patients referred for contrast-enhanced head and neck MRI from August 2020 to May 2021. Patients underwent 1.5-T MRI including contrast-enhanced spiral GRE (2:28 min), Cartesian GRE (4:27 min), and Cartesian TSE (3:41 min) sequences, acquired in rotating order across patients. Three radiologists independently assessed image quality measures using 5-point Likert scales, including conspicuity of prespecified lesions. One reader measured maximal extent of dental material artifact and contrast-to-noise ratio (CNR). Results: Thirty-one patients (13 male, 18 female; mean age 63.8 years) were enrolled. Nineteen patients had a focal lesion; 22 had dental material. Interreader agreement for image quality measures was substantial to excellent (Krippendorff's alpha, 0.681-1.000). Scores were better for spiral GRE than Cartesian GRE and Cartesian TSE for all readers (p .05) for lesion conspicuity (whole head and neck; neck only; head only), fat suppression, flow artifact, and foldover-type artifact. Scores were worse for spiral GRE than the other sequences for all readers (p<.05) for dental material artifact. Maximum extent of dental material artifact was 39.6±25.5 mm for spiral GRE, 35.6±24.3 mm for Cartesian GRE, and 29.6±21.4 mm for Cartesian GRE; CNR was 221.1±94.5 for spiral GRE, 151.8±85.7 for Cartesian GRE, and 153±63.2 for Cartesian TSE (p<.001 between spiral GRE and other sequences for both measures). Conclusion: 3D spiral GRE improves subjective image quality and CNR of head and neck MRI with shorter scan time versus Cartesian sequences, though exhibits larger dental material artifact. Clinical Impact: A spiral sequence may help overcome certain challenges of conventional Cartesian sequences for head and neck MRI.