Contrast-enhanced MR angiography of the hand.

Abstract

Contrast material-enhanced magnetic resonance (MR) angiography of the hand noninvasively provides information comparable to that provided by conventional angiography. It is a quick and easy examination that takes less than 5 minutes to perform and produces high-quality images with use of a dedicated surface coil that provides a high signal-to-noise ratio, allowing small pixel size and high spatial resolution. Contrast-enhanced MR angiography requires intravenous injection of gadopentetate dimeglumine and acquisition of a volumetric slab of image data from the hand. This information is then projected with a maximum-intensity-projection algorithm. The technique is generally robust with reproducible findings. Image interpretation requires an understanding of (a) the normal vascular anatomy and anatomic variants of the hand and (b) common vascular diseases. MR angiography of the hand is commonly used to create an arterial "road map" prior to surgery, manage traumatic transection, and identify emboli. Vascular malformations are readily identified and connective tissue disorders including vasculitis are well demonstrated with this technique, which can also be used to assess bone viability following trauma to the carpus or to evaluate the viability of vascularized bone. Common artifacts may be secondary to contracture deformities or "wraparound" effect. However, most potential pitfalls can be avoided by being vigilant.