Abstract: Objective To evaluate the reliability and effectiveness of double tube drainage under ultrasound-guided puncture in the treatment of parapharyngeal space abscess. Methods 15 patients, with single abscess in the parapharyngeal space and the diameter of abscess no less than 6 cm, were included into the study. Routine ultrasound and color Doppler were applied to locate the site for the puncture. After iodine disinfection and 2% lidocaine(5-10 mL)local anesthesia,A 10Fr's Skater drainage tracer was inserted into the deep side of the abscess, but the other one to a shallower side. The distance between the ends of two tubes was about 3cm. After removing the inner needle, the pus was extracted for bacterial culture and drug sensitive test. The rest of pus was pumped with a syringe as much as possible, and then rinse solution (500 mL of 0.9% sodium chloride injection plus 240 000 units of gentamicin and 250 mL of 0.2% metronidazole injection) was applied to irrigate abscess repeatedly. At the end of irrigation, a negative pressure suction device would be connected with the deeper tube. The above irrigation was performed twice a day. If the pus was too sticky to drain, 25 mL of 0.1% α-chymotrypsin saline solution would be injected into the abscess cavity, followed by approximately 20 mL of 0.5% metronidazole. In this way, the tubes were not removed until the rinse solution became clear. All the patients were treated with intravenous cefuroxime. Results The fever dropped or disappeared after 48-hour drainage. All of 15 patients were discharged with full recovery, and were followed up for six months without recurrence. Conclusion It is safe and reliable to drain the parapharyngeal space abscess with double tubes under ultrasound guide. Due to less complication and curative effects, it should be recommended.

Key words: Parapharyngeal space, Puncture, Abscess, Drainage, Ultrasonography