How are you? Complex regional pain syndrome (CRPS) usually affects the arm or leg, but can affect any area of the body including the face, head, and neck. The clinical characteristics were similar to those of CRPS elsewhere in the body, with the main features being burning pain, hyperalgesia, and hyperesthesia. It can be confined to a specific area also such as the eye. (ref: http://www.bethesdaphysiocare.com/professionals/pdf/jbmt_crps1_domm04.pdf) Hope this helps. Check with your doctor for proper evaluation. Take care and regards.