Abstract: Objective To compare the imaging findings of necrotizing fasciitis of the neck and other cervical space infections, and explore the relationship between the gas production of the infected bacteria and necrotizing fasciitis of the neck. Methods A retrospective study was conducted on 52 cases of cervical fascia space infection in our department from May 2015 to February 2020, including 18 cases of necrotizing fasciitis and 34 cases of non-necrotizing fasciitis. 18 cases underwent incision, debridement and catheter drainage in the necrotizing fasciitis group. 26 cases underwent incision, debridement and catheter drainage, and 8 cases underwent ultrasound-guided puncture biopsy and catheter drainage in the non-necrotizing fasciitis group. All cases were confirmed by operation or pathological biopsy and took purulent secretions for bacterial culture and drug sensitivity test during or after operation. All cases were examined by neck CT or MRI before operation. The previous history of surgical incision or puncture and the rupture of cervical space infection were excluded. Results In 18 cases of necrotizing fasciitis, there were 15 cases had air accumulation in the fascial space(83.3%); In 34 cases of non necrotizing fasciitis, 2 cases had air accumulation in the fascial space(5.9%).There was significant difference between the two groups(χ2=32.084 2, P<0.01). Bacterial culture results were positive in 14(77.8%)patients with necrotizing fasciitis. There were 5 cases of mixed infection, 13 cases of Streptococcus, 4 cases of Klebsiella pneumoniae, 1 case of Staphylococcus aureus, 1 case of Pseudomonas aeruginosa, and 1 cases of Acinetobacter baumannii in the necrotizing fasciitis group. In the non necrotizing fasciitis group, 12(35.3%)patients had positive bacterial culture results, and there were 4 Streptococcus, 2 Klebsiella pneumoniae, 1 Staphylococcus aureus, 1 coagulase negative staphylococcus, 1 Haemophilus influenzae, 1 Escherichia coli, 1 Enterobacter cloacae and 1 Acinetobacter baumannii in the non necrotizing fasciitis group. There was significant difference in the positive rate of bacterial culture between the two groups(χ2=8.496 7, P<0.01). Except one death in necrotizing fasciitis group, all other patients were cured. There was no recurrence after follow-up for 3-6 months. Conclusion The air accumulation in necrotizing fasciitis of neck is more than that in other infectious diseases of neck space.It is suggested that the gas production of bacteria may be closely related to the pathogenesis and development of necrotizing fasciitis of the neck. Early measures to block the generation and dissemination of gas may be of great significance for treatment.

Key words: Necrotizing fasciitis, Neck, Infection, Aerogenic bacteria, Fascia space