Abstract
BACKGROUND: Raynaud's syndrome is a commonly encountered disorder. The relationship between the grade of Raynaud's phenomenon and severity of vasoconstriction is unclear. Recently, various methods including colour Doppler ultrasonography have been used for assessment of vascularity of the extremities including fingers. CASE SUMMARY: A 53-year-old man had a 6-year history of Raynaud's phenomenon with typical tri-coloured changes proceeding from white, blue to red and slight pain and slight paresthaesia in the fingers of both hands when his fingers were exposed to cold. He was diagnosed with primary Raynaud's syndrome. After treatment with the calcium channel blocker amlodipine (5 mg once daily), a cold challenge did not induce Raynaud's phenomenon on the fingers in the present patient. After the cold challenge, colour Doppler ultrasonography showed that vascularity was markedly decreased or was absent, whereas there was little difference in skin colour of the fingers. DISCUSSION: In Raynaud's phenomenon, vasospasm may occur even if the symptoms are well-controlled with a calcium channel blocker. It is unlikely that clinical symptoms in patients with Raynaud's syndrome always reflect the severity of vasoconstriction in their fingers.