Application of negative pressure ball drainage on the perianal abscess in deep parapharyngeal space : a study of curative effect PAN You-zhen, ZHEN Jin-xia, ZHENG Zhen-lin. Department of Proctology Surgery, Gongli Hospital of Pudong New Area, Shanghai 200135, China. Corresponding author: ZHEN Jin-xia, E-mail: zhenjinxia8@163.com Abstract Objective To study the clinical effect of the negative pressure ball drainage in the application of postoperative perianal abscess in deep parapharyngeal space. Methods The 60 patients with perianal abscess in deep parapharyngeal space admitted between January 2007 and August 2008 at Gongli Hospital of Pudong New Area of Shanghai City were randomly divided into negative pressure ball group (treatment group n=30) and vaseline gauze group (control group n=30). Occurrence of pain, postoperative analgesic, postoperative drainage and wound healing time were compared respectively. Follow-up was performed in 3 months, 6 months and 12 months after the operation in order to observe the occurrence of secondary anal fistula. Results Occurrence of pain, postoperative analgesic, postoperative drainage and wound healing time of treatment group was lower than those of the control group (P <0.01). Incidence of secondary anal fistula of treatment group was lower than that of the control group (P <0.01). Conclusion Negative pressure ball is very suitable for postoperative drainage of perianal abscess in deep parapharyngeal space.