AIM: To investigate the incidence, characteristic and risk factors of high intraocular pressure(IOP)after 23- gauge pars plana vitrectomy(PPV)to provide a basis for treatment and prevention.

METHODS: We retrospectively studied 135 cases(146 eyes)who underwent 23-gauge PPV in our department and analyzed the factors that might be related to the state of high IOP. The ocular hypertension was defined as IOP ≥ 25mmHg at any time within 2 weeks after surgery. The statistical analysis was performed by Chi-square test. Single or combined pressure-lowering drugs were used according to the degree of IOP.

RESULTS: The high IOP occurred in 42 eyes(28.8%), and the average time was at 3.38 days after operation. The rate of IOP elevation in pure liquid exchange group, C₃F₈ tamponade group and silicone oil tamponade group were 14.5%, 33.3%, 39.3% respectively. There was statistical difference between C₃F₈ group, silicone oil tamponade group and pure liquid exchange group. The incidence rate of high IOP in non-cryotherapy group, partial retinal photocoagulation group, panretinal photocoagulation group or cryotherapy group were 13.6%, 27.4%, 34.5%, 35.7% respectively. There was no difference between the non-cryotherapy group and the partial retinal photocoagulation group, while the differences between the non-cryotherapy group and the other two groups were significant. High IOP would occur after any primary disease surgery, but the incidence was unbalanced. All elevated IOP were satisfactorily controlled.

CONCLUSION: The risk factors of high IOP after 23-gauge PPV are various,mainly related to intraocular tamponade and the treatment during the surgery. Influence of the primary disease on the high IOP mostly lies in the treatment. The high IOP after 23-gauge PPV mostly is transient which can be controlled by rational using of drugs.