[Diagnosis of focal liver lesions. The value of imaging systems]

Selection of the suitable modality for the detection or differential diagnosis of focal liver lesions must consider, in addition to its accuracy, such factors as on-site availability, the costs involved, and the stress to the patient. The preferred screening technique is ultrasonography which, however, has a high failure rate, in particular in the case of small lesions. In many cases computed tomography (CT) permits the correct diagnosis to be established. Both CT and ultrasonography make possible selective percutaneous biopsy. Magnetic resonance imaging is one of the most sensitive procedures, but is often not available - even in specialized centers. With this technique or blood pool scanning, hepatic hemangiomas found incidentally can be diagnosed in 90% of the cases. The diagnosis of focal modular hyperplasia continues to be difficult.