Sasan Partovi BS, Presenter: Nothing to Disclose

Anja Schulte, Abstract Co-Author: Nothing to Disclose

Ulrich A. Walker MD, Abstract Co-Author: Nothing to Disclose

Markus Aschwanden, Abstract Co-Author: Nothing to Disclose

Bjoern Jacobi MS, Abstract Co-Author: Nothing to Disclose

Matthias Loebe MD, PhD, Abstract Co-Author: Nothing to Disclose

Daniel Staub MD, Abstract Co-Author: Nothing to Disclose

Martin Takes MD, Abstract Co-Author: Nothing to Disclose

Rolf Walter Huegli MD, Abstract Co-Author: Nothing to Disclose

Deniz Bilecen MD, PhD, Abstract Co-Author: Nothing to Disclose

To analyze blood oxygen level–dependent (BOLD) signal intensity time course in calf muscles of patients with scleroderma and to compare BOLD key parameters with healthy volunteers.

7 patients with scleroderma (6 females, mean age 54±10 years) and 7 healthy volunteers (7 females, mean age 39±11 years) underwent fat-surpressed T2*-weighted single-shot multiecho echo-planar imaging on a whole-body magnetic resonance scanner at 3 T. A previously established ischemia-reactive hyperemia paradigm was performed by suprasystolic compression of an air-cuff at mid-thigh level and consecutive deflation. T2* signal time course was calculated from four calf muscles. In both groups two BOLD key parameters were determined for each subject: Hyperemia peak value (T2* max) and time to peak value (TTP). Statistical comparison between both groups was made using unpaired, two-sided student t test. P<0.05 was considered significant.

Mean T2* signal time course over all four calf muscles is demonstrated in Figure 1 for the scleroderma group (red line) and healthy volunteers (blue line). Mean T2* max with reference to the baseline was calculated as 4.26±6.81 % in the scleroderma group and 18.76±5.82 % in the healthy volunteer group, respectively (p=0.0016). Mean TTP was 281.44±12.23 seconds in the scleroderma group and 270.30±3.67 seconds in the control group, respectively (p=0.0414).

BOLD muscle MRI evaluation of scleroderma patients revealed significant reductions of T2* max and TTP in comparison with healthy volunteers. These changes are attributed to alterations of skeletal muscle microvessels in systemic sclerosis. Muscle BOLD effect has been shown to depend predominantly on the oxygen saturation of hemoglobin inside small vessels and capillaries, thus making it a promising diagnostic tool for scleroderma. To our knowledge this is the second investigation which reveals that scleroderma affects skeletal muscle microperfusion.

BOLD muscle MRI is a suitable, non-invasive imaging method for the detection of changes in skeletal muscle microperfusion, a hallmark of systemic sclerosis.

Partovi, S, Schulte, A, Walker, U, Aschwanden, M, Jacobi, B, Loebe, M, Staub, D, Takes, M, Huegli, R, Bilecen, D, Blood Oxygenation Level-dependent Magnetic Resonance Imaging of the Skeletal Muscle in Patients with Systemic Sclerosis and Comparison of Key Parameters with Healthy Volunteers.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11005642.html