An algorithmic approach to MR characterization of focal liver lesions in adults without cirrhosis.

Diagnosing both known and incidental liver lesions in the non-cirrhotic liver on MRI can be challenging. The radiologist can often narrow the diagnosis toward a diagnostic category using various sequences. Using an organized framework to guide the reader's differential diagnosis can be helpful. We present a sequential approach to the diagnosis of focal liver lesions, by first assessing background liver parenchymal signal intensity, then comparing the T1-weighted signal intensity of the reference organ(s), followed by comparing the T2-weighted signal intensity characteristics of lesion to fluid/spleen, and finally confirming using additional sequences including dynamic contrast-enhanced imaging, hepatobiliary imaging, diffusion weighted imaging, as well as clinical and laboratory testing and additional modalities. Using this stepwise framework can sequentially guide the reader toward a diagnosis.