Combined use of power Doppler and gray-scale sonography: a new technique for the assessment of inflammatory myopathy.
OBJECTIVE
Ultrasonography (US) is a utilitarian approach to the assessment of inflammatory myopathy (IM). Power Doppler sonography (PDS), a newer technique, enables detection of muscle vascularity and inflammation. We describe the combined use of PDS and gray-scale US in patients with IM.


METHODS
We studied 37 IM subjects and 6 control subjects. Clinical scores of muscle strength and function were obtained. The maximum score, 31, represented normal function and strength. Ultrasonographic gray-scale and vascularity results were scored 0-4. Nine subjects had serial assessments.


RESULTS
Subjects ranged from 16 to 83 years of age and were predominantly female. IM subjects had significantly abnormal lower clinical scores than controls, 23.0 +/- 5.8 vs 29.8 +/- 2.0 (p < 0.001). Mean peak gray-scale score was 2.1 +/- 0.96 compared to 0.5 +/- 0.84 for controls (p = 0.001), indicating atrophy in the IM group. Similar results were found for average gray-scale scores. Peak vascularity scores were higher in IM, 2.7 +/- 0.8 vs 2.2 +/- 0.3 (p = 0.007). Disease of longer duration was significantly associated with more abnormal gray-scale scores and lower creatine phosphokinase (CPK) levels. PDS scores were more abnormal in disease of shorter duration. There was a negative association between functional scores and inflammatory scores on serial assessment.


CONCLUSIONS
Sonography is a valuable tool in the assessment of IM. Gray-scale and PDS findings were significantly different between IM and control subjects. Abnormal gray-scale US scores were associated with disease of longer duration and lower CPK levels. In contrast, increased vascularity on PDS detected disease of shorter duration and varied with the clinical course more than did gray-scale findings.
Meng
C
C
Hospital for Special Surgery, New York, and Weill-Medical College of Cornell University, New York, New York, USA. Mengc@hss.edu
Adler
R
R
Peterson
M
M
Kagen
L
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003402:Creatine Kinase / Q000097:blood; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000098:blood supply; D009220:Myositis / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D012039:Regional Blood Flow; D018608:Ultrasonography, Doppler / Q000379:methods*
D003402:Creatine Kinase