Osteomyelitis of the diabetic foot: MR imaging-pathologic correlation.
OBJECTIVE
To evaluate the efficacy of magnetic resonance (MR) imaging for the diagnosis of osteomyelitis in the diabetic foot by using anatomic and histologic studies of the resected tissue as a standard of reference.


METHODS
Thirteen diabetic patients with high clinical suspicion of osteomyelitis underwent a total of 15 MR examinations before surgery. Correlation was made between MR findings and the histologic features of the resected tissue, which included 57 bones.


RESULTS
Maximum signal intensity on the T2-weighted or short inversion time inversion-recovery images of the bones was due to osteomyelitis (prospective sensitivity, 90%; specificity, 71%). Eighteen bones with increased signal intensity showed only edema of the marrow. The range of signal intensity in edema overlapped that in osteomyelitis but was lower. The use of gadopentetate dimeglumine improved delineation of soft-tissue inflammatory masses, but this contrast material was not useful in distinguishing osteomyelitis from edema.


CONCLUSIONS
Marrow edema cannot be reliably distinguished from osteomyelitis with MR imaging. Gadopentetate dimeglumine is of limited use. Some previously published false-positive reports of osteomyelitis were most likely due to edema of the marrow. MR imaging is useful in planning surgery of the infected diabetic foot, as it enables reliable distinction between normal and abnormal areas.
Craig
J G
JG
Department of Radiology, Henry Ford Hospital, Detroit, MI 48202, USA.
Amin
M B
MB
Wu
K
K
Eyler
W R
WR
van Holsbeeck
M T
MT
Bouffard
J A
JA
Shirazi
K
K
D000328:Adult; D000368:Aged; D000671:Amputation, Surgical; D001855:Bone Marrow Diseases / Q000175:diagnosis / Q000473:pathology; D003287:Contrast Media; D017719:Diabetic Foot / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D003949:Diagnostic Techniques, Surgical; D004338:Drug Combinations; D004487:Edema / Q000175:diagnosis / Q000473:pathology; D005189:False Positive Reactions; D005260:Female; D005534:Foot Diseases / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D005682:Gadolinium; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008297:Male; D008536:Meglumine; D008875:Middle Aged; D009942:Organometallic Compounds; D010019:Osteomyelitis / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D010347:Patient Care Planning; D004369:Pentetic Acid / Q000031:analogs & derivatives; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003287:Contrast Media; D004338:Drug Combinations; D009942:Organometallic Compounds; D008536:Meglumine; D004369:Pentetic Acid; D005682:Gadolinium; D019786:Gadolinium DTPA