HEAD AND NECKTc 99m diphosphonates concentrate in cerebral lesions only when the bloodbrain barrier has been damaged by cerebral infarction (ref) , tumor or inflammation. Bone tracers also localize in extraaxial lesions such as subdural hematomas, meningiomas (ref) and dural calcifications. (ref)
Cerebral infarction (ref). An anterior image of a bone scintigram (A) shows increased uptake in the left parietal region, which corresponds to an area of decreased attenuation on an unenhanced CT (B).
Cerebral infarction (ref). Anterior (A) and lateral (B) images of a bone scintigram show increased uptake in the left parietal region, which corresponds to an area of decreased attenuation on an unenhanced CT (C).
Meningioma (ref). Posterior (A) and lateral (B) bone scintigraphic images show increased uptake in the right posterior fossa, which correspond to a heavily calcified mass seen on an unenhanced CT (C).
Dural Calcification (ref) (A) Anterior and (B) lateral views of a bone scintigram show increased radiotracer accumulation along the superior mid-sagittal plane and asymmetric radiotracer uptake along the left fronto-temporal region. (C) Lateral view of the skull demonstrates dense calcifications of the dural falx.
Free Pertechnetate (A-B) Bone scintigrams in anterior view show increased radiotracer accumulation in the expected region of the oral cavity and the thyroid glands. |
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