Radiation-induced sarcomas of the head and neck

Table 2 Advantages and disadvantages of computed tomography and magnetic resonance imaging in head and neck oncologic imaging

CT	MRI
Advantages
Fast	Superior soft tissue resolution including better assessment of perineural invasion, intracranial extension of disease, marrow infiltration
Well tolerated	Multi-planar imaging capability, better definition of cradiocaudal extent
Relatively inexpensive	Less image degradation caused by artifacts arising from dental amalgam
Provides assessment of tissue composition (vascularity, lipid content etc.)	Does not involve ionizing radiation
Ideal at demonstrating cortical bone erosion	Contrast material is less likely to produce allergic reaction
Disadvantages
Involves exposure to small amounts of radiation	May take more time to perform
Inferior soft tissue resolution compared with MRI	More expensive
Higher risk of allergic reactions and nephrotoxicity associated with the use of iodinated contrast agents	Lower patient tolerance; Claustrophobic patients may need sedation
	Contraindicated in patients with pacemakers and other implanted metallic devices which may malfunction following exposure to strong magnetic fields
	More susceptible to motion artefact

CT: Computed tomography; MRI: Magnetic resonance imaging.