[Magnetic resonance tomography in the follow-up after the embolization of arteriovenous malformations of the central nervous system].

Interventional embolisation is an accepted treatment for intracranial or spinal arteriovenous malformations. Since multiple embolizations are often required, noninvasive repeatable follow-up studies are desirable. The aim of this study is to demonstrate the usefulness of T2-weighted images, MR angiography, and gadolinium-DTPA first-pass studies for post-embolisation follow-up studies. Five patients with arteriovenous malformations, four cerebral and one spinal, were studied prospectively before and repeatedly after single or multiple embolizations. A total of 26 MRI studies (1.5 T Magnetom, Siemens AG) were performed. The combination of T2-weighted images, MR angiography, and gadolinium-DTPA first-pass studies nicely demonstrated the arteriovenous malformations and the effect of embolisation which ranged from negligible to almost complete. While contrast-enhanced T1-weighted images and contrast-enhanced MR-angiography seemed to be of little more value than unenhanced studies, gadolinium-DTPA first-pass studies appeared to be more sensitive than T2-weighted images or MR-angiography because of their high intrinsic sensitivity to regional blood flow and volume. In the spine, T2-weighted images and MR-angiography were too insensitive to detect arteriovenous malformations, whereas gadolinium-DTPA first-pass studies sensitively detected the malformation and the changes after embolizations.