title: Assessment of skeletal muscle perfusion using contrast-enhanced ultrasonography.
abstract: OBJECTIVE
  The purpose of this study was to develop a clinically applicable examination method to assess perfusion of the skeletal muscle using contrast-enhanced ultrasonography (CEUS) analyzing replenishment kinetics of microbubbles.
  
  
  METHODS
  Power Doppler sonography (7 MHz) after intravenous bolus injection of 10 mL of a microbubble contrast agent was used to repeatedly examine the perfusion of the right biceps muscle at rest and after defined exercise in 10 healthy volunteers. Parameters of perfusion, such as local blood volume, blood flow velocity, and perfusion, were calculated by a modified analysis of replenishment kinetics. For validation, CEUS was correlated with venous occlusion plethysmography (VOP) examining the right forearm flexor muscles at rest and after defined exercise.
  
  
  RESULTS
  The CEUS examination was easily feasible and was able to depict the physiologic large variability of the right biceps muscle perfusion at rest (mean +/- SD, 3.0 +/- 2.3 [approximately mL/s x 100 mg]) compared with the results after exercise (22.9 +/- 11.0 [approximately mL/s x 100 mg]). The perfusion calculated with VOP significantly correlated with the CEUS parameters perfusion (r = 0.81; P < .001) and blood volume (r = 0.82; P < .001). The calculated mean blood flow velocity in the right forearm flexor muscles raised from 0.41 +/- 0.24 mm/s at rest to 0.64 +/- 0.39 mm/s after exercise, showing a significant correlation with the CEUS perfusion (r = 0.72; P < .001).
  
  
  CONCLUSIONS
  Muscle perfusion can be easily and quantitatively assessed with CEUS. Compared with VOP, CEUS allows for a separate analysis of different muscle groups, unaffected by skin perfusion. Its application may be of particular interest in the diagnosis and monitoring of pathologic microvascularization in myositis or diabetic obstructive disease.
authors.affiliation: German Cancer Research Center, INF 280, D-69120 Heidelberg, Germany. m.krix@dkfz.de
authors.forename: Martin
authors.initials: M
authors.lastname: Krix
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Weber
authors.forename: Holger
authors.initials: H
authors.lastname: Krakowski-Roosen
authors.forename: Hagen B
authors.initials: HB
authors.lastname: Huttner
authors.forename: Stefan
authors.initials: S
authors.lastname: Delorme
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
authors.forename: Wulf
authors.initials: W
authors.lastname: Hildebrandt
mesh_terms: D001132:Arm / Q000098:blood supply; D001783:Blood Flow Velocity; D001810:Blood Volume; D003287:Contrast Media; D006801:Humans; D045423:Microbubbles; D018482:Muscle, Skeletal / Q000098:blood supply* / Q000000981:diagnostic imaging*; D011134:Polysaccharides; D012039:Regional Blood Flow / Q000502:physiology; D018608:Ultrasonography, Doppler
chemical_list: D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508