Raynaud Phenomenon
Type: Symptom
Definition
An exaggerated, painful spasm of the small blood vessels in the fingers upon exposure to cold.
Clinical Details
The structural fibrosis aggressively narrows the tiny arteries supplying blood to the extremities, highly sensitizing them to thermal changes or emotional stress. Upon encountering a cold trigger, the vessels snap entirely shut, turning the fingers stark white, then blue from oxygen deprivation, and finally burning red as blood returns. These severe ischemic attacks frequently lead to painful, necrotic ulcers on the fingertips.