In this study，the investigators used methylene blue compound injection intradermally to treat NNEDs patients. Patients with a diagnosis of biopsy proven NNEDs from Maternal and Child Health Hospital of Hubei Province (China) between October 2013 to October 2016 were recruited. Every patient received intradermal mixed methylene blue compound injection twice. All patients were observed during the hospitalization at the first injection, and two weeks later they received the second injection at the outpatient department. Ages, itching scores, percentage of hypopigmented skin, and recurrences were recorded through inquiry and physical examination before and after treatment. Side effects (such as edema, fever and vulva pain) were also recorded. All women were followed up 1, 3, 6, 12 months after treatment, which included inquiry and physical examination.