A pilot study of regional perfusion and oxygenation in calf muscles of individuals with diabetes with a noninvasive measure.
OBJECTIVE
To assess alterations in the regional perfusion and oxygenation of the calf muscles in individuals with diabetes.


METHODS
Age-matched individuals with (n = 5) and without diabetes (n = 6) were investigated. Skeletal muscle perfusion, oxygen extraction fraction, and oxygen consumption rate were measured by newly developed noncontrast magnetic resonance imaging (MRI) techniques. The subjects lay supine on the MRI table with their foot firmly strapped to a custom-built isometric exercise device. The measurements were performed at rest and during an isometric plantar flexion muscle contraction.


RESULTS
Individuals without diabetes had up to a 10-fold increase in muscle perfusion, 25% elevation in muscle oxygen extraction fraction, and a 12-fold increase in oxygen consumption rate in the calf during the plantar flexion isometric contraction. In patients with diabetes, the increases in these parameters were only up to sixfold, 2%, and sixfold, respectively. Exercise oxygen consumption rate was inversely associated with blood HbA1c levels (r(2) = .91).


CONCLUSIONS
This is the first study to quantify regional skeletal muscle oxygenation in patients with diabetes using noncontrast MRI and warrants additional study. Attenuation of perfusion and oxygenation during exercise may have implications for understanding diabetic complications in the lower extremities.
Department of Radiology, Washington University School of Medicine, St. Louis, Mo. Electronic address: zhengj@wustl.edu.
Jie
J
Zheng
Program in Physical Therapy, Washington University School of Medicine, St. Louis, Mo; Department of Orthopedic Surgery, Washington University School of Medicine, St. Louis, Mo.
Mary K
MK
Hasting
Department of Radiology, University of North Carolina, Chapel Hill, NC.
Xiaodong
X
Zhang
Department of Radiology, Washington University School of Medicine, St. Louis, Mo.
Andrew
A
Coggan
Department of Radiology, Washington University School of Medicine, St. Louis, Mo.
Hongyu
H
An
Department of Radiology, Washington University School of Medicine, St. Louis, Mo.
Darrah
D
Snozek
Department of Surgery, Washington University School of Medicine, St. Louis, Mo.
John
J
Curci
Department of Radiology, Washington University School of Medicine, St. Louis, Mo; Program in Physical Therapy, Washington University School of Medicine, St. Louis, Mo.
Michael J
MJ
Mueller
D000368:Aged; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D003925:Diabetic Angiopathies / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D005240:Feasibility Studies; D006442:Glycated Hemoglobin / Q000378:metabolism; D006439:Hemodynamics; D006801:Humans; D007537:Isometric Contraction; D007866:Leg; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000098:blood supply* / Q000378:metabolism / Q000503:physiopathology; D010101:Oxygen Consumption; D056888:Patient Positioning; D055420:Perfusion Imaging / Q000379:methods*; D010865:Pilot Projects; D012039:Regional Blood Flow; D016683:Supine Position
D015415:Biomarkers; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human