Giant-cell arteritis: concordance study between aortic CT angiography and FDG-PET/CT in detection of large-vessel involvement

Eur J Nucl Med Mol Imaging. 2017 Dec;44(13):2274-2279. doi: 10.1007/s00259-017-3774-5. Epub 2017 Jul 24.


Purpose: The purpose of our study was to assess the concordance of aortic CT angiography (CTA) and FDG-PET/CT in the detection of large-vessel involvement at diagnosis in patients with giant-cell arteritis (GCA).

Methods: We created a multicenter cohort of patients with GCA diagnosed between 2010 and 2015, and who underwent both FDG-PET/CT and aortic CTA before or in the first ten days following treatment introduction. Eight vascular segments were studied on each procedure. We calculated concordance between both imaging techniques in a per-patient and a per-segment analysis, using Cohen's kappa concordance index.

Results: We included 28 patients (21/7 women/men, median age 67 [56-82]). Nineteen patients had large-vessel involvement on PET/CT and 18 of these patients also presented positive findings on CTA. In a per-segment analysis, a median of 5 [1-7] and 3 [1-6] vascular territories were involved on positive PET/CT and CTA, respectively (p = 0.03). In qualitative analysis, i.e., positivity of the procedure suggesting a large-vessel involvement, the concordance rate between both procedures was 0.85 [0.64-1]. In quantitative analysis, i.e., per-segment analysis in both procedures, the global concordance rate was 0.64 [0.54-0.75]. Using FDG-PET/CT as a reference, CTA showed excellent sensitivity (95%) and specificity (100%) in a per-patient analysis. In a per-segment analysis, sensitivity and specificity were 61% and 97.9%, respectively.

Conclusions: CTA and FDG-PET/CT were both able to detect large-vessel involvement in GCA with comparable results in a per-patient analysis. However, PET/CT showed higher performance in a per-segment analysis, especially in the detection of inflammation of the aorta's branches.

Keywords: 18FDG-pet/Ct; CT angiography; Giant-cell arteritis; Large-vessel vasculitis.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aorta / diagnostic imaging*
  • Computed Tomography Angiography*
  • Female
  • Fluorodeoxyglucose F18*
  • Giant Cell Arteritis / diagnostic imaging*
  • Humans
  • Male
  • Middle Aged
  • Positron Emission Tomography Computed Tomography*
  • Retrospective Studies


  • Fluorodeoxyglucose F18