This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: CT SCAN, Subject name: Radiology
Investigation not useful in Multiple Myeloma 
Select and explain. 
A. CT SCAN, B. MRI, C. BONE SCAN, D. PET
C: BONE SCAN
Answer: C: BONE SCAN 
Explanation: The Bone scan is a nuclear scan done using Tc99m-MDP and shows a hot spot in areas of osteoblastic activity. As Multiple myeloma has osteolytic metastasis, So bone scan is not sensitive for detecting these bone mets and usually appear as cold areas Multidetector CT (MDCT) is more sensitive in detecting Myeloma and a low-dose technique can be used to limit radiation to the patient