Observation of the Comfort and Efficacy of CO2 Laser Combined With Cryo 6 for Burn or Linear Scars.

Inclusion Criteria: 1. Age 14-60 years; 2. The patient agreed to participate in the experiment and signed the informed consent by himself/herself or his/her legal representative; 3. The clinical diagnosis was burn scar or post-operative linear scar, and the total area was more than 5 cm2. 4. No other treatment such as laser or chemical exfoliation was performed on the lesion within the recent half year. 5. Skin lesions were free of bleeding, ulceration, infection and other conditions affecting the visual field of laser treatment. Exclusion Criteria: 1. Patients with an active or established sun tan; 2. Patients with history of allergic reaction to to topical anesthesia; 3. Patients with history of keloid scarring, abnormal wound healing and/or prone to bruising; 4. Skin malignant tumors or precancerous lesions; 5. Patients with diabetes, heart disease, epilepsy, connective tissue disease, etc.; 6. Pregnant or breastfeeding patients; 7. Patients with recent skin infections (such as viral and bacterial infections); 8. Patients who are using other methods to treat similar diseases; 9. Patients who had taken isotretinoin within the past year; 10. History of cryoglobulinaemia; 11. History of cold agglutinin disease and cold haemolysis; 12. History of cold urticaria; 13. Parts of the body with impaired circulation; 14. Raynaud's disease; 15. Parts of the body with impaired sensitivity; 16. Trophic disorders; 17. Hypersensitivity to cold; 18. Patients with mental illness; 19. Other ineligible patients.