Study of temporal arteritis by B-mode Ultrasound and Color Duplex J.A. Jimenez-Lasanta, C. Roque, L. Castro, E. Barluenga, A. Olive, A. Olazabal HUGTIP-Badalona. SPAIN

Purpose  To investigate the accuracy of Color Doppler Ultrasound compared with biopsy in the diagnosis of temporal arteritis (TA).  To propose to the light of the results and review of literature that this technique should be included in the diagnostic algorithm of the TA.

Topic review 1.- What is this disease?  TA is a granulomatous polyarteritis of the large and medium vessels and, in particular, of the superficial temporal artery.  TA appears in patients over 50 years, peaking in the 80s, with a female predominance.  Etiology is unknown but it is related to genetic predisposition, owing to a granulomatous reaction by a phenomenon of autoimmunity to infectious agents, such as Chlamydia pneumoniae, papovirus B19 and varicella zoster virus.

Topic review 2.- Current diagnosis  Diagnostic criteria were proposed by the American College of Rheumatology in 1990:  Tenderness of the temporal artery or decreasing the pulse.  Localized headache of recent onset.  ESR above 50 in the 1st hour.  Age over 50 years  Changes characteristics in biopsy of the temporal artery (key technique)  If 3 of these 5 criteria are found, there is a sensitivity of 93%, with a specificity of 91.2%.  In 9-20% of patients with TA the biopsy results negative.

Temporal artery biopsy Disadvantages Sensitivity for TA diagnosis is 56-91%. It is an invasive technique. Complication rate is around 0.5%, including facial nerve involvement, infection, skin necrosis or stroke secondary to impaired collateral circulation. In those cases with segmental disease, the biopsy results negative in 9-44% of patients.

Proposal: Doppler Ultrasound  Good screening test owing to 3 points : 1.A high sensitivity. 2.A high negative predictive value. 3.Low cost and morbidity.

Normal patient Main temporal artery Occipital branch Frontal branch Normal Duplex flow

Material and methods  The study was conducted by an expert sonographer (over 15 years’ experience)  A total of 38 patients were sent from departments of Rheumatology and Internal Medicine.  Patients’ average age was 71 years with an interval between 58 and 90 years.  High frequency probes were used, between 8-15 Mhz.

Methodology Morphological study  Anatomical route was found in longitudinal and transverse sections at three points : 1.Main trunk above the tragus. 2.Parietal branch of the fork 15 mm. 3.Occipital branch of the fork 25 mm.  Two aspects were assessed, 1.Presence of hypoechoic halo at these points, with thickness ranging from 0.7 to 1.3 mm, the largest being of 2 mm. 2.Arterial stenosis morphology.

Hypoechoic halo in the main trunk. Morphological criteria (cross section)

Methodology Hemodynamic Study  Calculation of systolic and diastolic velocities.  Stenosis hemodynamic when there was Increased peak systolic doubled between pre-stenotic and post-stenotic areas or Enlarged spectral curve or Presence of post-stenotic turbulence in the area  Better assessment of stenosis with contrast US (12 cases studied)

Main trunk stenosis (speed pre-estenosis )

Speed post-estenosis (main trunk)

Stenosis in the frontal branch

Speeds pre-stenosis Frontal branch

Speeds post-stenosis Frontal branch

Occipital branch B-mode stenosis Discontinuous segment

Occipital branch segmental involvement with high-speed post-stenosis

Pre-stenotic speed PS in the parietal branch, after contrast US Improving diagnosis with Contrast US Post -stenotic speed PS after contrast US

Pathologic Diagnosis Inflammatory infiltrate of lymphocytes and macrophages. Adopting organization granulomatous and multinucleated giant cells. Fragmentation of elastic lamina

Statistical analysis Assessment of the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV). Efficiency or overall value of the test (VGT).

Results  Presence of hypoechoic halo stenosis or morphological criteria, Sensitivity: 78% Specificity: 89% PPV: 81% NPV: 93% VGT: 82%

Results  More morphological criteria and hemodynamic criteria Sensitivity 100% Specificity 80% PPV 68% NPV 100% VGT 88%

Results: Biopsies  Negative: 60%.  A 51% of biopsies could have been prevented

Conclusion  Background: - Meta-analysis published in 2005 by Karass, this technique has been proved useful for TA.  False positives are rare  The absence of a hypoechoic halo and stenosis in a patient with clinical suspicion of TA rules out the diagnosis and permit to avoid the biopsy.  High negative predictive value of the test: - The absence of halo or stenosis in a patient with low suspicion of AT rules out the possibility of the disease.

Conclusion  Our results: Agree with the background. Utility of Doppler US in the diagnosis of TA is controversial, being a browser dependent technique Sensitivity and specificity variable according to studies In some patients during follow-up, disappearance of morphological criteria in the 25 days after corticosteroid treatment was observed in our study Good screening test for TA diagnosis because it is noninvasive and able to predict patients who will not require a biopsy US Contrast helps in the assessment of stenosis in the areas of hypoechoic halo with increased thickness

Suggested Readings 1.Schmith WWA, Kraft HE et al. Color duplex ultrasonography in the diagnosis of temporal arteritis. N Engl J Med. 1997;337: Karassa FB, Matsagas MI, et al. Meta-analysis: tests performance of ultrasonography for giant-cell arteritis. Ann Intern Med. 2005;142: JM Zaragozá, A. Plaza et al. Valor de la ecografía Doppler en el diagnóstico de la arteritis de la temporal. Med Clín (Barc.) 2007;129(12): Dasgupta B, Hassan N et al. Giant cell arteritis: recent advances and guideliness for management. Clin Exp Rhreumatol 2007;25(1 Suppl 44):S62-5.