Cranial osteomyelitis: diagnosis and follow-up with In-111 white blood cell and Tc-99m methylene diphosphonate bone SPECT, CT, and MR imaging.

Purpose: To assess the usefulness of indium-111 white blood cell and technetium-99m methylene diphosphonate bone single photon emission computed tomography (SPECT), computed tomography (CT), and magnetic resonance (MR) imaging in cranial osteomyelitis.
Materials and Methods: Twenty-six cases (25 patients: 13 male, 12 female; mean age, 55 years) of suspected osteomyelitis were evaluated. Sixteen were postoperative. Final diagnosis was established by means of bone culture in 18 cases and clinical follow-up in eight.
Results: Of 35 CT scans, 10 were true-positive (TP); three false-negative (FN); 13, true-negative (TN); one, false-positive (FP); and eight, equivocal. Of 36 SPECT scans, 19 were TP; 13, TN; one, FP; one, FN; and two, equivocal. Of 11 MR images four were TP; five, TN; and two, FN.
Conclusion: CT is best for differentiation between soft-tissue and bone infection. MR imaging is best for assessment of the calvaria and skull base. SPECT is best for assessment of altered bone and may be the best technique for follow-up.