Assessment of Skeletal Muscle Perfusion using Contrast-Enhanced Ultrasonography: Technical Note

Abstract

Background: Intravenous contrast-enhanced ultrasonography is a recently developed technique for assessment of tissue perfusion, but has not been used for assessment of skeletal muscle perfusion.

Methods: We studied a 42-year-old woman in whom myonecrosis was suspected due to systemic vasculitis and ischemia. The biceps brachii (right) and quadriceps femoris (vastus medialis) on right-hand side and subsequently left-hand side were imaged. Intravenous bolus of activated perflutren lipid microspheres was injected and B-Flow color mode (brown color) was used within a selected region of interest to image the passage of contrast through muscle parenchyma throughout three cardiac cycles.

Results: Visual interpretation of muscle perfusion was performed based on the maximal intensity of contrast in the muscle, and the speed of contrast replenishment. No deficits were noted in the perfusion pattern. The arterial phase demonstrated stellate vascularity, centrifugal filling, and homogeneous hypervascularity at peak enhancement.

Conclusions: The bolus of contrast resulted in good signal persistence and satisfactory imaging for multiple muscle groups.

Keywords: Muscle perfusion; contrast; lipid microspheres; muscle ischemia; myonecrosis; ultrasonography.

Figure 1. The antero-posterior (A) and cross-sectional (B) images in T2-weighted images. There is diffuse high T2 signal in thigh muscles, more prominent in the medial and posterior compartments. There is mild fatty infiltration of the muscle with marbled appearance suggestive of mild atrophy.

Figure 2. Arterial phase contrast-enhanced ultrasound images obtained with maximum-intensity-projection technique show sequential images obtained in arterial phase of contrast-enhanced ultrasonography in biceps brachii (right A–D) and quadriceps femoris (vastus medialis, right E–G). The images show stellate vascularity, centrifugal filling, and homogeneous hypervascularity at peak enhancement.