title: Diagnosing an atypical site of giant cell arteritis with magnetic resonance angiography: a case report.
abstract: BACKGROUND
  Giant cell arteritis typically involves the temporal arteries, but can involve other cranial arteries. Temporal artery biopsy is the mainstay for the diagnosis of giant cell arteritis; however, biopsy may be problematic if giant cell arteritis involves other cranial arteries that are inaccessible for sampling. In these situations, magnetic resonance angiography is a useful, non-invasive adjunctive method in the diagnosis of giant cell arteritis. In this case report, we describe a case of giant cell arteritis involving only the occipital artery which was revealed by magnetic resonance angiography.
  
  
  METHODS
  A 67-year-old Caucasian man was admitted to our hospital with a 4-week history of malaise, fever, and mild occipital headaches. There were no other positive findings on physical examination. Laboratory studies were remarkable for normocytic anemia, raised inflammatory markers, and mildly deranged liver function tests. To exclude intracranial pathology, he underwent a cranial magnetic resonance imaging with gadolinium, which demonstrated a thickened wall and mural enhancement of his right occipital artery, consistent with giant cell arteritis. His temporal arteries were normal. His occipital arteries were not accessible for biopsy and he was commenced on high-dose prednisolone (60 mg daily). His symptoms resolved completely after a week of glucocorticoid steroid treatment and he was well on 5 mg of prednisolone once a day on follow-up.
  
  
  CONCLUSIONS
  While magnetic resonance angiography may not replace the need for biopsy, it may have a diagnostic role in suspected giant cell arteritis, such as when the involved arteries are inaccessible for biopsy.
authors.affiliation: Department of General Medicine, Flinders Medical Centre, Flinders Drive, Bedford Park, South Australia, 5042, Australia.
authors.forename: Boon L
authors.initials: BL
authors.lastname: Tan
authors.affiliation: School of Medicine, Flinders University, Bedford Park, South Australia, Australia.
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Liu
authors.affiliation: Flinders Private Hospital, Flinders Dr, Bedford Park, SA, 5042, Australia.
authors.forename: Tuck Y
authors.initials: TY
authors.lastname: Yong
authors.affiliation: Department of Medical Imaging, Flinders Medical Centre, Flinders Drive, Bedford Park, South Australia, 5042, Australia.
authors.forename: Chrismin C
authors.initials: CC
authors.lastname: Tan
authors.affiliation: Department of General Medicine, Flinders Medical Centre, Flinders Drive, Bedford Park, South Australia, 5042, Australia. jordan.li@sa.gov.au.|School of Medicine, Flinders University, Bedford Park, South Australia, Australia. jordan.li@sa.gov.au.
authors.forename: Jordan Y
authors.initials: JY
authors.lastname: Li
mesh_terms: D000368:Aged; D000893:Anti-Inflammatory Agents / Q000633:toxicity*; D005334:Fever / Q000209:etiology; D013700:Giant Cell Arteritis / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology*; D005938:Glucocorticoids / Q000627:therapeutic use; D006261:Headache / Q000209:etiology; D006801:Humans; D008111:Liver Function Tests / Q000379:methods*; D018810:Magnetic Resonance Angiography; D008297:Male; D011239:Prednisolone / Q000627:therapeutic use*; D013699:Temporal Arteries / Q000000981:diagnostic imaging / Q000473:pathology*; D016896:Treatment Outcome
chemical_list: D000893:Anti-Inflammatory Agents; D005938:Glucocorticoids; D011239:Prednisolone
keywords: Extracranial involvement; Giant cell arteritis; Magnetic resonance angiography; Vasculitis