A hybrid molecular imaging technique that targets both bone cell activity and immune response can help physicians better distinguish osteomyelitis from Charcot foot, according to study results presented at the Society of Nuclear Medicine and Molecular Imaging Annual Meeting.
Current imaging standards advise an additional bone marrow scan if initial scanning comes back positive for white blood cell activity in foot bone, indicating osteomyelitis, but also possibly caused by hyperplasia, a proliferation of cells in the bone marrow of patients with Charcot joint. In the study, researchers investigated new data analysis for single photon emission computed tomography (SPECT) and computed tomography (CT), which together provide both biological and anatomical information about diabetic food disorders. The combination of imaging agents technetium-99mhydroxymethylene diphosphonate (HDP) — a biomarker for targeting bone—and a white blood cell or leukocyte biomarker that indicates areas of infection provided comparative imaging data that can make an accurate diagnosis possible with a single scan.
A total of 22 diabetic patients were imaged with dual-isotope SPECT/CT for suspected diabetic foot infection. Scanning revealed 27 lesions. Ten were confirmed as osteomyelitis, and nine of the 10 lesions correlated with adjacent deep soft tissue infection in white blood cell SPECT/CT scan. Researchers analyzed patterns of wash-out of the white blood cell imaging agent to differentiate actual osteomyelitis from Charcot joint. Initial scans for 15 of the 17 lesions that were confirmed to represent Charcot joint showed white blood cell wash-out. An additional bone marrow scan confirmed these results, indicating that dual-isotope bone and white blood cell SPECT/CT scan can positively identify osteomyelitis from Charcot joint without an additional bone marrow scan.
“Optimizing imaging protocol for detection and localization of diabetic foot conditions aids attending physicians in distinguishing between true bone infection and bone marrow overgrowth associated with Charcot joint,” Sherif Heiba, MD, director of nuclear medicine residency program and associate professor of radiology at Mount Sinai School of Medicine, stated. “This helps patients considerably by not only eliminating unnecessary scans but also reducing imaging time and the total radiation dose required to make that determination.”
For more information:
Heiba S. Abstract #654. Presented at: the Society of Nuclear Medicine and Molecular Imaging 60th Annual Meeting. June 8-12, 2013, Vancouver, British Columbia, Canada.
Disclosures: The researchers have no relevant financial disclosures.