To the Editor:

We thank Bley et al for their interest, and agree that noninvasive modalities for assessing vasculitis are promising and merit further study. The use of high-resolution magnetic resonance imaging to detect inflammatory changes in the temporal artery is one intriguing approach; we look forward to seeing this technique validated in larger patient populations.

Despite the great potential of noninvasive techniques in the evaluation of large vessel vasculitis, caution is still warranted. It is difficult to say how early successes will fare in community practice, especially when these techniques are applied by practitioners who are inexperienced in the assessment of vasculitis. In many studies of noninvasive modalities, the differences between normal and abnormal are slight, and may be difficult to discern even by trained examiners. Considering the high stakes involved in diagnosing giant cell arteritis correctly, biopsy is likely to remain the test of choice for some time to come and the gold standard against which new approaches must be measured.

Philip Seo MD*, John H. Stone MD, MPH*, * The Johns Hopkins Vasculitis Center Baltimore, MD.