Role of MR and CT in diagnostics

Abstract

Radiologic assessment is important for the diagnosis of vascular malformations. MR is the best modality to evaluate the extent of the lesions and the relation with the adjacent structures. Low-flow malformations can be differentiated from high-flow lesions using the characteristics of the signal on different sequences. Routine sequences are T1- and T2-weighted SE images with fat suppression and/or STIR and post-contrast T1-weighted images. On spin-echo sequences, the vessels in the high-flow malformations appear as a signal void, and on gradient echo, the vessels are bright. 3D gradient-echo acquisitions gadolinium-enhanced and non-contrast imaging angiography using time-of-flight and true fast imaging with steady-state precession (TrueFISP) are useful to specify the type and the extension of the vascular malformation. More recently, time-resolved imaging with a high temporal resolution allows for a dynamic analysis of the vascular malformation and is particularly useful to identify the arterial feeders of a high-flow malformation. CT is useful to assess bone destruction and calcifications and also for three-dimensional reformation.