TL-201 UPTAKE IN EOSINOPHILIC GRANULOMA OF THE FRONTAL BONE - COMPARISON WITH TECHNETIUM-99M-MDP IMAGING

An 11-yr-old female presented with a 6-wk history of left upper lid te nderness and left eye lacrimation. Left lateral supraorbital mass and left preauricular lymph node were the only significant physical examin ation findings. On skull x-ray, a left frontal bone defect was noted. CT and MRI showed a soft-tissue mass in the area of the bone defect. B one scintigraphy exhibited peripheral uptake within the central photon deficient area. With Tl-201 SPECT, high uptake was noted on early and delayed images. Diagnosis of eosinophilic granuloma was performed by biopsy. Since thallium uptake was seen in the area where photon defici ency was exhibited by Tc-99m-MDP scintigraphy, we speculate that thall ium SPECT could detect eosinophilic granuloma when radiographic skelet al survey or radionuclide bone scan are equivocal. It could also rule out multiple bone involvement and recurrence or regrowth after therapy .