Preoperative Imaging of Charcot Neuroarthropathy in Diabetic Patients: Comparison of Ring PET, Hybrid PET, and Magnetic Resonance Imaging

Introduction: The treatment of Charcot neuroarthropathy in the feet
of diabetic patients has undergone fundamental changes in the last
few years. Formerly, treatment was almost exclusively limited to
nonoperative measures; since the late 1990s, however, current
practice has shifted to early, stage-appropriate surgical therapy.
The objective of this prospective study was to investigate the
value of two types of positron emission tomography (PET) in the
preoperative evaluation of diabetic patients with Charcot foot
deformities. Materials and Methods: Ring 18FFDG
(2-fluoro-2-deoxy-glucose) and hybrid PET were compared to magnetic
resonance imaging (MRI). MRI, ring PET, and hybrid PET imaging were
used as part of the preoperative evaluation of 16 patients with
type II diabetes mellitus. The diagnosis of Charcot neuropathy of
the foot requiring operative treatment had been made on the basis
of clinical and radiographic criteria. Results: Of 39 Charcot
lesions confirmed at surgery, 37 were detected by ring PET, 30 by
hybrid PET, and 31 by MRI. Conclusions: PET (ring or hybrid) can be
used in the evaluation of patients with metal implants that would
compromise the accuracy of MRI. Another advantage of PET is its
ability to distinguish between inflammatory and infectious
soft-tissue lesions, and between osteomyelitis and Charcot
neuroarthropathy. The differentiation between Charcot
neuroarthropathy and florid osteomyelitis provides the surgeon with
important additional information that often is unavailable from
MRI. Because it provides important additional data, ring PET may be
preferable to radiography and MRI in the preoperative evaluation of
patients with Charcot neuroarthropathy of the foot. Hybrid PET,
because of its poorer resolution compared to ring PET, appears less
suitable for routine clinical application.