Femoral head perfusion and composition: MR imaging and spectroscopic evaluation of patients with systemic lupus erythematosus and at risk for avascular necrosis.
OBJECTIVE
To measure fat content and relative marrow perfusion of the femoral head in patients at risk for avascular necrosis.


METHODS
Thirteen patients with systemic lupus erythematosus (SLE) without avascular necrosis and with long-term corticosteroid treatment and 12 healthy subjects were evaluated. Hip perfusion was assessed with gadolinium-enhanced T1-weighted magnetic resonance (MR) imaging. Marrow composition in the femoral head and neck was measured with hydrogen-1 MR spectroscopy.


RESULTS
Percentage fat content in the femoral head was similar between the two groups (SLE patients, 77% +/- 5 [standard deviation]; healthy subjects, 78% +/- 6; P = .74). Rate of enhancement of the femoral head was significantly higher in the SLE than the healthy group (11%/min +/- 6 vs 6.9%/min +/- 3, respectively; P = .05), was inversely related to fat content in healthy subjects (r = -.74, P = .02), and was more variable in the SLE group (r = -.53, P = .11).


CONCLUSIONS
Perfusion of the femoral head is inversely related to marrow fat content in healthy and is higher in SLE patients without hip avascular necrosis.
D000273:Adipose Tissue / Q000473:pathology; D000293:Adolescent; D000328:Adult; D001853:Bone Marrow / Q000098:blood supply / Q000473:pathology; D016022:Case-Control Studies; D003287:Contrast Media; D004338:Drug Combinations; D005260:Female; D005270:Femur Head / Q000098:blood supply* / Q000473:pathology*; D005272:Femur Neck / Q000098:blood supply / Q000473:pathology; D005682:Gadolinium; D019786:Gadolinium DTPA; D006621:Hip Joint / Q000098:blood supply / Q000473:pathology; D006801:Humans; D007089:Image Enhancement; D008180:Lupus Erythematosus, Systemic / Q000188:drug therapy / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008536:Meglumine; D008875:Middle Aged; D009942:Organometallic Compounds; D010020:Osteonecrosis / Q000473:pathology*; D004369:Pentetic Acid / Q000031:analogs & derivatives; D011241:Prednisone / Q000008:administration & dosage / Q000627:therapeutic use; D012039:Regional Blood Flow; D012307:Risk Factors
D003287:Contrast Media; D004338:Drug Combinations; D009942:Organometallic Compounds; D008536:Meglumine; D004369:Pentetic Acid; D005682:Gadolinium; D019786:Gadolinium DTPA; D011241:Prednisone