Clinical Presentation

Fig. 21.1

Technique

• A 20 mCi dose of ^99mTc-MDP is administered intravenously.

• Whole-body images of the skeleton are obtained 3 hours after tracer administration.

• A 1024 × 256 matrix is used for whole-body images.

• Emphasize the importance of oral hydration to improve soft tissue and bladder clearance.

Image Interpretation

Whole-body images demonstrate increased focal uptake in the sternoclavicular joints bilaterally and in the sternomanubrial joint. A focus of decreased uptake is noted in the sacrum with adjacent irregular activity in the sacroiliac joints.

Fig. 21.2

Differential Diagnosis

• Metastatic disease (eg, lung, thyroid, or renal cancer or multiple myeloma; less likely to be seen with prostate or breast cancer)

• Attenuation artifact (metallic object in back pocket, belt)

• Prosthetic joint (hip, knee)