Any side effect related to the BoNT-A injections will be asked to report. There has not been reported to have serious side effect from local injection of BoNT-A to the urethral sphincter. However, the potential side effects, such as exacerbation of urinary incontinence, allergy and anaphylactic shock should be informed to the patients and carefully monitor the postoperative conditions. Urinalysis will be checked at the first follow-up 1 and 2 week after BoNT-A injection. Antibiotics will be given if patients have significant urinary tract infection.