Non-invasive imaging in the diagnosis and management of Takayasu's arteritis.

OBJECTIVES Takayasu's arteritis (TA) is a rare disease, in which early diagnosis and assessment of treatment efficacy remain a problem. Signs and symptoms may be non-specific and conventional blood tests unreliable, with vascular inflammation often persisting in the face of a normal acute phase response. The current "gold standard" investigation, x ray angiography, is invasive and only identifies late, structural changes in vessels. Recently, non-invasive imaging methods have shown promise in the assessment of patients with TA. METHODS The invasive and non-invasive imaging performed on all patients in the rheumatology department at the Hammersmith Hospital between May 1996 and May 2002 who fulfilled the ACR criteria for TA were reviewed. All patients were clinically active at diagnosis and were treated with high dose oral prednisolone and additional oral or intravenous immunosuppression. RESULTS Non-invasive imaging methods ([(18)F]fluorodeoxyglucose positron emission tomography ([(18)F]FDG-PET) and magnetic resonance imaging (MRI)) provided important additional information about disease activity ([(18)F]FDG-PET) and progression of vessel wall thickening (MRI) when compared with x ray angiography. CONCLUSIONS Non-invasive imaging methods provide useful additional information towards the diagnosis and management of TA. Such techniques may allow earlier diagnosis and more accurate assessment of response to treatment than conventional clinical assessment and/or angiography. Non-invasive imaging is likely to be useful in the management of other large vessel vasculitides.