[Contact plate thermography with cold provocation tests for the diagnosis of Raynaud's phenomenon]

Since the contact plate thermography became a serious method to diagnose a vasospasm in form of Raynaud's phenomenon but absolute data for the behavior of the hand temperature under effects of cold were missing, 80 normal persons and 47 patients with a Raynaud's phenomenon were examined to determine the re-warming time after a defined cold exposition and to distinguish normal finger blood flow from pathological. To control the cold exposition of the hands, water immersions with three different temperatures and exposition times were used: 20 degrees C and 3 min., 15 degrees C and 2 min., 10 degrees C and 1 min. The measured re-warming time is the time, in that the thermographical color impression is the same as before the exposition to the cold. Patients with a Raynaud's phenomenon have a significant longer re-warming time than normal persons. The re-warming time of 70-80% of the group of normal persons is 10 min. for the 3 min./20 degrees C test, 15 min. for the 2 min./15 degrees C test and 25 min. for the 1 min./10 degrees C test. These times are a sign for normal behavior; times that lie above these are abnormal and make the diagnosis of a vasospasm reasonable. The diagnosis of a Raynaud's phenomenon is only possible with the typical clinical symptomatic.