Comparison of 2- and 3-dimensional shoulder ultrasound to magnetic resonance imaging in a community hospital for the detection of supraspinatus rotator cuff tears with improved worktime room efficiency

Purpose: The purpose of this study was to evaluate whether 3-dimensional (3D) volumetric acquisition of shoulder ultrasound (US) data for supraspinatus rotator cuff tears is as sensitive when compared with conventional 2-dimensional (2D) US and routine magnetic resonance imaging (MRI), and whether there is improved workroom time efficiency when using the 3D technique compared with the 2D technique. Methods: In this prospective study, 39 shoulders underwent US and MRI examination of their rotator cuff to confirm the accuracy of both the 2D and 3D techniques. The difference in sensitivities was compared by using confidence interval analysis. The mean times required to obtain the 2D and 3D US data and to review the scans were compared by using a 1-tailed Wilcoxon test. Results: Sensitivity and specificity of 2D US in detecting supraspinatus full- and partial-thickness tears was 100% and 96%, and 80% and 100%, respectively, and similar values were obtained with 3D US at 100% and 100%, and 90% and 96.6%, respectively. Analysis of the confidence limits of the sensitivities showed no significant difference. The mean time (±SD) of the overall 2D examination of the shoulder, including interpretation was 10.02 ± 3.28 minutes, whereas, for the 3D examination, it was 7.08 ± 0.35 minutes. Comparison between the 2 cohorts when using a 1-tailed Wilcoxon test showed a statistically significant difference (P < .05). Conclusion: 3D US of the shoulder is as accurate as 2D US when compared with MRI for the diagnosis of full- and partial-thickness supraspinatus rotator cuff tears, and 3D US examination significantly reduced the time between the initial scan and the radiologist interpretation, ultimately improving workplace efficiency. (author)