Soft Tissue Uptake on Bone Scan

Tc-99m MDP can be taken up by soft tissues, usually due to ossification and calcification. The most common causes for each organ are listed.

• Brain: Infarction.
• Heart: Infarction, among other possibilities.
• Kidneys: Renal cortical uptake greater than spine uptake is abnormal. Can be seen with metastatic calcification from hypercalcemia (e.g., in hyperparathyroidism), renal cortical necrosis (radiation, drugs), hemoglobinopathies (e.g., sickle cell disease).
• Liver: Usually metastases if focal. Diffuse uptake may indicate excess aluminium.
• Lungs: Metastatic calcification from hypercalcemia (e.g., in hyperparathyroidism), pleural effusion, fibrothorax, neoplasm (primary or metastatic), alveolar microlithiasis, radiation.
• Muscle: Rhyabdomyolysis or polymyositis if diffuse. Myositis ossificans or tumor if focal.
• Spleen: Infarction (e.g., in sickle cell disease).
• Stomach: Metastatic calcification from hypercalcemia (e.g., in hyperparathyroidism).