MRI Appearances of Liver Carcinoma after Gamma Knife Therapy / 实用放射学杂志

ABSTRACT

Objective To study the value of unenhanced and dynamic contrast-enhanced MR imaging in follow-up of liver carcinomas after gamma knife therapy.Methods 57 patients examined by MR imaging after gamma knife therapy were analyzed retrospectively,and compared with outcome of AFP.Results Lesions treated with gamma knife therapy on precontrast imaging showed 4 kinds of appearances(1) Slightly low signal intensity on T1WI and slightly high signal intensity on T2WI.(2)Slightly low signal intensity on both T1WI and T2WI.(3)Slightly high signal intensity on T1WI,isointensity and slightly high signal heterogeneous intensity on T2WI.(4)Slightly high signal intensity on both T1WI and T2WI.The necrotic lesions showed sustained ring-shaped or honeycomb enhancement or patching enhancement in hepatic tissue around the lesions with lesions unenhancing.Recurrent lesions or new lesions were enhanced in arterial phase,followed by rapid wash-out in the delay phase.The rate of completely necrosis was 93.5% in small liver carcinoma group(