Diagnostic Value of Diffusion Weighted MRI Versus Conventional MRI in The Diagnosis of Rotator Cuff Tears

Background: The rotator cuff is a group of four muscles and tendons that surround the shoulder joint. These muscles and tendons provide stability in the shoulder, attached around the head of the humerus bone, encircling it like a cuff. This study aimed to compare diagnostic value of diffusion-weighted MRI imaging to conventional MRI especially fat suppression imaging sequences in the detection of rotator cuff tears. Methods: This case control study included 70 participants who were divided into two groups; Case group: 50 patients with clinically suspected tear of rotator cuff tendons having history of trauma and Control group: 20 healthy adult individuals with no history of trauma or significant shoulder pain as a control group. Results: According to conventional MRI, all 53 suspected rotator cuff tears were confirmed, giving high signal on T2/fat suppressed image while all controls gave normal low signal, with a statistically significant difference between both groups (P < 0.001). Conventional MRI had sensitivity of 100% and PPV of 100% with an overall accuracy of 100% for positive rotator cuff tears diagnosis. Conclusion: Diffusion MRI has good sensitivity and diagnostic accuracy in diagnosis of rotator cuff tears. However, the signal in diffusion MRI is greatly affected by time interval between insult and MRI examination so the earlier MRI can be done, the better the signal in diffusion images. ADC images correlation reveals T2 shine through artifacts rather than true diffusion restriction. In addition, diffusion MRI has lower spatial resolution and low image quality than conventional MRI images.