Table 4.

Summary and comparison of the main features, advantages and limitations of CT and MRI in MM and other PCDs

	CT	MRI
Main features	- Morphological imaging in clinical routine, functional imaging (DECT) only in study settings - Highest sensitivity for the detection of osteolytic bone lesions - Visualization of bone marrow infiltration in the extremities - Gold standard for the assessment of spinal stability in vertebral fractures - Necessary/supportive for the planning of radiotherapy, surgeries and biopsies - Valuable for the assessment of treatment response and relapse during follow-up to evaluate the extent and dynamics of bone destruction as the most clinically relevant parameter	- Morphological and functional imaging (DWI) in clinical routine - Additional functional imaging options (DCE, chemical shift with fat fraction maps) in study settings - Highest sensitivity for the detection of bone marrow infiltration - Depiction of medullary infiltration pattern - Depiction of non-osteolytic bone marrow infiltration prior to bone destruction - Gold standard for the assessment of spinal cord and nerve root compression - Gold standard for the differentiation of benign and malignant vertebral fractures - Prognostic relevance - Possible value for the assessment of treatment response and relapse during follow-up when functional imaging (DWI) is applied
Technical advantages	- Better availability - Shorter acquisition time - Higher patient comfort - Lower costs - No administration of contrast agents required for evaluation of MBD	No radiation exposure
Technical limitations	- Radiation exposure	- Limited availability - Longer acquisition time - Patient discomfort, may be significant in patients with claustrophobia, or older metal implants
Administration of contrast agents	- Adverse impact on kidney function in patients with preexistent renal impairment - Possible allergic reactions - Possible thyrotoxicosis	- Adverse impact on kidney function in patients with preexistent renal impairment - Disassociation and deposition of linear GBCAs

Abbreviations: CT: computed tomography; MRI: magnetic resonance imaging; DECT: dual-energy computed tomography; DWI: diffusion-weighted imaging; DCE: dynamic contrast-enhanced; GBCAs: gadolinium-based contrast agents