The predictive value of the halo sign in color Doppler ultrasonography of the temporal arteries for diagnosing giant cell arteritis.

Abstract

The PPV of the halo sign in US of the temporal arteries is unsatisfactory for diagnosing GCA. However, the NPV is very high. Thus the lack of a halo can practically serve to rule out a diagnosis of GCA, and precludes the need for a biopsy in most instances.