Abstract for presentation at 38th Annual Scientific Meeting of the Australian and New Zealand Society of Nuclear Medicine 2008

[18F]FDG PET-CT in the Diagnosis of Large Vessel Vasculitis

  • Dr John Kok, Department of Nuclear Medicine & P.E.T., Liverpool Hospital, Australia
  • Dr Michael Lin, Department of Nuclear Medicine & P.E.T., Liverpool Hospital, Australia
  • Dr Harry Patapanian, Department of Rheumatology, Bankstown Hospital, Australia
  • Dr Meena Shingde, Department of Pathology, Royal Prince Alfred Hospital, Australia
  • Dr Peter Lin, Department of Nuclear Medicine & P.E.T., Liverpool Hospital, Australia
  • Mr Peter Peralta, Department of Nuclear Medicine & P.E.T., Liverpool Hospital, Australia

    • The diagnosis of large vessel vasculitis and the assessment of its extent and activity are challenging. Positron emission tomography (PET) is a metabolic imaging modality based on the regional distribution of the radiolabeled glucose analogue [18F]FDG. Activated inflammatory cells have been shown to over-express glucose transporters and to accumulate increased glucose and structurally similar substances like [18F]FDG. Large vessel vasculitic conditions are characterized by inflammation. Cases of patients with large vessel vasculitis and abnormal increased uptake on [18F]FDG PET scans have been described by a few groups. We describe a case of a 66 year old woman presenting with constitutional symptoms and raised inflammatory markers. A [18F]FDG PET-CT scan performed in our department demonstrated abnormal increased tracer uptake within the vessel walls of the ascending aorta, aortic arch and proximal descending aorta and a markedly dilated ascending aorta, highly suggestive of mural inflammation/aortitis. Histological findings after surgery revealed chronic inflammatory aortitis. This confirmed the diagnosis of Giant Cell Arteritis and aortitis based on the American College of Rheumatology (ACR) criteria. Our case demonstrates the usefulness of [18F]FDG PET-CT in the diagnosis of large vessel vasculitis. The recent advent of combined functional and anatomic imaging with PET-CT scanners allows anatomic correlation and exact localization of lesions. We conclude that [18F]FDG PET is effective in assessing the activity and extent of large vessel vasculitis and is a useful tool in the diagnosis and evaluation of this condition. Combined PET-CT scanning provides further anatomic information and improves diagnostic confidence.

    Conference Organiser - ICMS Pty Ltd