The prevalence of neovascularity in rotator cuff tendinopathy: comparing conventional Doppler with superb microvascular imaging.

ABSTRACT

AIMS: To determine the prevalence of neovascularity in the supraspinatus tendon of patients presenting with clinically painful unilateral rotator cuff tendinopathy (RCT) using conventional colour Doppler ultrasound (CDU), power Doppler ultrasound (PDU), and superb microvascular imaging (SMI). The association between Doppler findings and clinical scores was also assessed. METHODS: The bilateral supraspinatus of consecutive patients presented with unilateral RCT clinically were evaluated with grey-scale ultrasound (tendon thickening, heterogeneous echotexture, and hypoechogenicity), CDU, PDU, and SMI. The prevalence of neovascularity and grey-scale changes on duplex imaging techniques were analysed. The relationship between neovascularity on CDU, PDU, SMI, and pain/disability as determined using a visual analogue scale (VAS) and the Oxford Shoulder Score (OSS) were assessed. RESULTS: Fifty-nine patients (mean age 53 years, 39 women) were recruited. Of the symptomatic supraspinatus tendons, 42.4% (25/59) demonstrated neovascularity on SMI, compared to 6.8% (4/59) on PDU and 5.1% (3/59) on CDU. Of the asymptomatic supraspinatus tendons, 5.1% (3/59) depicted neovascularity on SMI but not on conventional Doppler techniques. SMI showed a significant correlation with the VAS (r2 = 0.560, p<0.001) and OSS (r2 = 0.62, p<0.001). PDU weakly correlated with the VAS and OSS (r2 = 0.312, p=0.016; r2 = 0.260, p=0.047, respectively) while CDU did not show a significant relationship. CONCLUSION: SMI is superior in demonstrating neovascularity and shows better correlation with pain and functional deficit compared to conventional Doppler in patients with painful RCT. SMI also showed vascularity to a lesser degree in the asymptomatic tendon. Further large-scale studies are needed to prove the diagnostic value of SMI in the assessment of RCT.