Quantitative dynamic contrast-enhanced ultrasound for the functional evaluation of the skeletal muscle microcirculation in systemic sclerosis.

PURPOSE: The purpose was to evaluate skeletal muscle microcirculation by means of quantitative dynamic contrast-enhanced ultrasound (DCEUS) in patients with systemic sclerosis (SSc). METHODS: DCEUS imaging of the gastrocnemius muscle was performed with phospholipid-stabilized microbubbles filled with sulfur hexafluoride in 12 patients with SSc and 12 healthy volunteers. The fitted time intensity curves (TIC) during the first 3 minutes after administration of the contrast agent bolus were analysed. Time course parameters of the TIC were compared between patients and healthy volunteers. RESULTS: Peak enhancement, wash-in area under the curve and was-out area under the curve was decreased in the patient group versus healthy volunteers (168 versus 248 AUp = 0.291; 2193 versus 3314p = 0.198; 4948 AU x sec versus 8948 AU x secp = 0.037). In the SSc patients the mean transit time and wash-in perfusion index were numerically, but not statistically lower than in the healthy volunteers, but rise and fall time were similar. CONCLUSION: On the microvascular level in SSc patients versus their healthy counterpart key parameters related to blood volume were decreased and perfusion parameters showed a slight diminishment in the patient population. These results suggest a component of impaired skeletal muscle microcirculation in SSc patients. [ABSTRACT FROM AUTHOR]