Temporal Artery Ultrasound to Diagnose Giant Cell Arteritis: A Practical Guide

The Common Carotid Artery in the Ultrasound Evaluation of Giant Cell Arteritis

OBJECTIVES

Vascular ultrasound is commonly used to diagnose giant cell arteritis (GCA). Most protocols include the temporal arteries and axillary arteries, but it is unclear which other arteries should be included. This study investigated whether inclusion of intima media thickness (IMT) of the common carotid artery (CCA) in the ultrasound evaluation of GCA improves the accuracy of the examination.

METHODS

We formed a fast-track clinic to use ultrasound to rapidly evaluate patients with suspected GCA. In this cohort study, patients referred for new concern for GCA received a vascular ultrasound for GCA with the temporal arteries and branches, the axillary artery, and CCA.

RESULTS

We compared 57 patients with GCA and 86 patients without GCA. Three patients with GCA had isolated positive CCA between 1 and 1.49 mm, and 21 patients without GCA had isolated positive CCA IMT. At the 1.5-mm CCA cutoff, 4 patients without GCA had positive isolated CCA, and 1 patient with GCA had a positive isolated CCA. The sensitivity of ultrasound when adding carotid arteries to temporal and axillary arteries was 84.21% and specificity 65.12% at an intima media thickness (IMT) cutoff of ≥1 mm and 80.70% and 87.21%, respectively, at a cutoff of ≥1.5 mm.

CONCLUSION

Measurement of the CCA IMT rarely contributed to the diagnosis of GCA and increased the rate of false-positive results. Our data suggest that the CCA should be excluded in the initial vascular artery ultrasound protocol for diagnosing GCA. If included, an IMT cutoff of higher than 1.0 mm should be used.

Headache attributed to giant cell arteritis complicated with rheumatic polymyalgia diagnosed with F18-fluorodeoxyglucose positron emission tomography and computed tomography: a case report

Giant cell arteritis (GCA) is a kind of systemic vasculitis affecting individuals over 50 years old and is often the cause of new-onset headaches in older adults. Patients with GCA sometimes have rheumatic polymyalgia (PMR). The diagnosis of GCA generally depends on clinical manifestation, elevated erythrocyte sedimentation rate (ESR) or C-reactive protein, and positive imaging findings commonly obtained by ultrasound or temporal artery biopsy. In this study, we report a case of an 83-year-old woman with a new-onset headache and an elevated ESR. The result of the temporal artery ultrasound did not distinguish between vasculitis and atherosclerosis. The F18-fluorodeoxyglucose positron emission tomography and computed tomography (18F FDG PET-CT) were performed and suggested large vessel vasculitis with temporal artery involvement. In addition, polyarticular synovitis and bursitis were also revealed. Finally, the diagnosis of secondary headache attributed to CGA complicated with PMR was established. The patient experienced remission of symptoms after glucocorticoid therapy. PET can become a powerful tool for diagnosis and differential diagnosis when the ultrasound result is ambiguous and a biopsy is not obtained.

Temporal Artery Ultrasound for the Diagnosis of Giant Cell Arteritis in the Emergency Department

Giant cell arteritis (GCA), known as temporal arteritis, is a serious condition requiring immediate treatment to prevent complications. GCA can be difficult to diagnose, especially in emergency department (ED) settings where ophthalmology and rheumatology services may be unavailable. Temporal artery ultrasound (TAUS) is a valuable tool for diagnosing GCA. In the ED, TAUS can be used to quickly rule out GCA and avoid unindicated steroid treatment, which can cause serious morbidity in elderly patients. This article discusses the use of TAUS for evaluating patients with suspected GCA in the ED and its potential to expedite treatment and ensure appropriate, timely follow-up for patients with this potential vision and life-threatening condition.

Color Doppler Eye Ultrasonography in giant cell arteritis: differential diagnosis between arteritic and non-arteritic sudden blindness

PURPOSE

Temporal (TA) and axillary (AXA) arteries Color Doppler Ultrasonography (CDUS) is the most reliable diagnostic technique for the diagnosis of giant cell arteritis (GCA), displaying high sensitivity and specificity. Nevertheless, CDUS is still poorly performed in the common clinical practice, being employed only by rheumatologists with a relevant expertise in this field. Color Doppler Eye Ultrasound (CDEUS) is a procedure variously employed in ophthalmology and preliminary findings have displayed a possible role also in the diagnostic work-up of GCA. Aim of this study was to assess whether CDEUS may play a role in the differential diagnosis between arteritic and non-arteritic blindness.

METHODS

We prospectively included all patients evaluated since September 2021 to May 2022 by our Ophthalmology Unit for sudden blindness and referred to our Vasculitis Clinic in the suspicion of GCA. All patients underwent complete ophthalmological evaluation, routine blood tests, AxA and TA CDUS and CDEUS. According to the definite diagnosis, patients were divided in the following subgroups: (A) patients suffering from arteritic central retinal artery occlusion (CRAO), (B) patients suffering from non-arteritic CRAO, (C) patients suffering from arteritic anterior ischemic optic neuropathy (AION), (D) patients suffering from non-arteritic AION.

RESULTS

During the observational period, we included a total of 25 patients suffering from sudden blindness and referred to Vasculitis Clinic for ruling out GCA. Patients belonging to group A showed no flow or reduced flow within the territory of central retinal artery (CRA), no "spot sign" and positive TA CDUS; on the other hand, patients from group B presented normal TA CDUS, no flow or reduced flow within the territory of CRA and the presence of "spot sign". Conversely, no relevant difference was evidenced at CDEUS in patients with and without arteritic AION.

CONCLUSION

Our preliminary data displayed a good reliability of CDEUS in distinguishing between arteritic and non-arteritic CRAO, while no difference was assessed between arteritic and non-arteritic AION. Since AION represents the most common presentation of cranial GCA, CDEUS does not seem a reliable procedure in the diagnostic work-up of GCA and should be restricted only to the exclusion of thrombo-embolic occlusions within the territory of central retinal artery.

Comparison of halo and compression signs assessed by a high frequency ultrasound probe for the diagnosis of Giant Cell Arteritis

OBJECTIVE

To evaluate the diagnosis performances of halo and compression signs alone and combined, assessed by a high frequency 22-MHz probe, and test their agreement in giant cell arteritis (GCA).

METHODS

In this cross-sectional study on patients suspected with GCA, halo sign was defined as hypo or iso-echogenic circumferential aspect of the vessel wall in transverse or longitudinal view; and compression sign was defined as visibility of the vessel wall upon transducer-imposed compression of the artery. Agreement of the two signs was tested using the Cohen's kappa statistic.

RESULTS

A total of 80 patients (50% women) were included with a mean age of 74.4 years. Twenty participants (25%) were ultimately treated for GCA. Halo and compression signs have respective prevalences of 35% and 48%, with respective sensitivity and specificity of 80% and 80% for the halo sign; and 85% and 65% for the compression sign. The kappa coefficient for the global agreement of the two signs was 0.67 (95% confident interval: 0.54-0.85). Combination of the two signs give a sensitivity of 80% and a specificity of 81.7%.

CONCLUSION

Halo and compression signs assessed by a high frequency probe, show a good level of agreement for the diagnosis of GCA and improve ultrasound specificity when combined together.

Cervical duplex ultrasound for the diagnosis of giant cell arteritis with vertebral artery involvement

Giant cell arteritis (GCA) is a systemic inflammatory arteriopathy of medium and large-sized arteries, predominantly affecting branches of the external carotid artery. Ischemic stroke has been reported in 2.8-7% of patients diagnosed with GCA. The majority of ischemic strokes may involve the posterior circulation as a result of vertebral and/or, less frequently, of basilar artery vasculitis. Prompt diagnosis is crucial since high-dose corticosteroid treatment is highly effective in preventing the occurrence or recurrence of ischemic complications, including posterior circulation ischemic stroke in cases with vertebrobasilar involvement. Cervical duplex sonography (CDS) of the temporal arteries is a powerful diagnostic tool with high sensitivity and specificity for the diagnosis of GCA. In cases with clinical suspicion or a temporal artery ultrasonographic confirmation of GCA, a detailed evaluation of the cervical, axillary, and intracranial arteries with CDS and transcranial-duplex-sonography, respectively, should be part of the ultrasound examination protocol. Specifically, signs of extracranial vertebral artery wall inflammation ("halo" sign) and focal luminar stenoses may be accurately depicted by ultrasounds in high-risk patients or individuals with ischemic stroke attributed to GCA. In this review, we present three cases of GCA and posterior circulation ischemic complications that were initially evaluated with comprehensive neurosonology protocol and were promptly diagnosed with GCA based on the characteristic "halo" sign in the temporal and vertebral arteries. In addition, we discuss the relevant literature concerning the utility of CDS for the early diagnosis of GCA, focusing on the subtype with extracranial arterial involvement, particularly that of the vertebral arteries.