Plethysmography measures the speed at which the vein fills with blood. It is used to diagnose peripheral arterial disease (PAD), Reynaud’s disease and thoracic outlet syndrome.
There is no preparation for the upper extremity digital exam. Please see Raynaud’s and Thoracic Outlet Testing.
For the lower extremity digital exam, to prepare you will be asked to remove clothing that covers your feet and will be given a gown or shorts to wear. Blood pressure cuffs may be placed around the toes. During the exam the blood pressure and circulation may be measured in the toes.