The diagnostic value of ultrasonography-derived edema of the temporal artery wall in giant cell arteritis: a second meta-analysis

Abstract

BackgroundUltrasonography of temporal arteries is not commonly used in the approach of patients with suspected giant cell arteritis (GCA) in clinical practice. A meta-analysis of primary studies available through April 2004 concluded that ultrasonography could indeed be helpful in diagnosing GCA. We specifically re-examined the diagnostic value of the ultrasonography-derived halo sign, a dark hypoechoic circumferential thickening around the artery lumen, indicating vasculitic wall edema, in GCA.MethodsOriginal, prospective studies in patients with suspected GCA that examined ultrasonography findings of temporal arteries using the ACR 1990 classification criteria for GCA as reference standard, published through 2009, were identified. Only eight studies involving 575 patients, 204 of whom received the final diagnosis of GCA, fulfilled technical quality criteria for ultrasound. Weighted sensitivity and specificity estimates of the halo sign were assessed, their possible heterogeneity was investigated and pooled diagnostic odds ratio was determined.ResultsUnilateral halo sign achieved an overall sensitivity of 68% (95% CI, 0.61-0.74) and specificity of 91% (95% CI, 0.88-0.94) for GCA. The values of inconsistency coefficient (I2) of both sensitivity and specificity of the halo sign, showed significant heterogeneity concerning the results between studies. Pooled diagnostic odds ratio, expressing how much greater the odds of having GCA are for patients with halo sign than for those without, was 34 (95% CI, 8.21-138.23). Diagnostic odds ratio was further increased to 65 (95% CI, 17.86-236.82) when bilateral halo signs were present (sensitivity/specificity of 43% and 100%, respectively). In both cases, it was found that DOR was constant across studies.ConclusionTemporal artery edema demonstrated as halo sign should be always looked for in ultrasonography when GCA is suspected. Providing that currently accepted technical quality criteria are fulfilled, halo sign's sensitivity and specificity are comparable to those of autoantibodies used as diagnostic tests in rheumatology. Validation of revised GCA classification criteria which will include the halo sign may be warranted.

Large Giant Cell Arteritis with Eye Involvement

“…"dark halo" sign -a typically hypoechoic, circumferential wall thickening around the lumen of an inflamed temporal artery -which represents vessel wall edema and a characteristic finding in temporal arteritis (TA)/GCA (Arida et al, 2010). b. stenoses are documented by blood-flow velocities, which are more than twice the rate recorded in the area of stenosis compared with the area before the stenosis, with wave forms demonstrating turbulence and reduced velocities behind the area of stenosis.…”

Application of Orbital Sonography in Neurology

“…The diagnosis of TA can by firmly supported by hypoechoic vasculitic vessel wall changes in the temporal arteries (so called "halo"-sign) (Arida et al 2010), but the negative predictive www.intechopen.com value is only 68% and thus far not sufficient to rule out that disease. In patients with sudden retinal blindness and borderline symptoms for TA (only 2-3 positive ACR-criteria), a visible "spot sign" could be very helpful to rule out vasculitis, as could be demonstrated in the above-mentioned prospective study (Ertl et al, submitted).…”

The use of transdermal optical coherence tomography to image the superficial temporal arteries

“…A meta-anaylsis reported the sensitivity and specificity for unilateral halo sign as 68% and 91%, respectively. 2 Ultrasound is cheaper, noninvasive, permits longitudinal scanning for disease activity, and can be quicker to organise than TAB but requires experience. 2,3 Magnetic resonance imaging and angiography 4 has also been used to image the superficial temporal artery, but access and high expense has limited its widespread use.…”