AIM: To investigate the mechanism of intraocular pressure(IOP)elevation after scleral buckling surgery with ultrasound biomicroscopy(UBM).

METHODS: A totally of 156 patients 161 eyes who underwent scleral buckling surgery operated by professor An-Huai Yang during July, 2011 and February, 2012 were selected in this retrospective study. All the patients were grouped by high IOP and normal IOP(not suffering from glaucoma and without glaucoma family history). The structure ofocular anterior segment was observed with UBM in all patients following scleral buckling surgery. We analyzed the relationship between IOP and the structure parameter of ocular anterior segment to investigate the mechanism of high IOP after scleral buckling surgery.

RESULTS: By UBM, the main causes of high IOP after scleral buckling surgery wereadhesion of iris to trabecular meshwork and closure of anterior chamber angle. The high IOP group and normal IOP group had statistical differences in anterior chamber depth(ACD)(t=2.003, P=0.048), angle opening distance₅₀₀(AOD₅₀₀),(t=2.071, P=0.049)and ciliary body thickness(CBT)(t=1.932, P=0.038).

CONCLUSION: UBM is effective in observation of the structure of ocular anterior segment after scleral buckling surgery and intraocular hypertension is a common complication. ACD, AOD₅₀₀ and CBT changes are related to IOP changes soon after operation(in 2 weeks). The edema and forward rotation of ciliary body, the narrow of anterior chamber angle are the mainly factors resulting in high IOP after scleral buckling surgery. The high IOP group has a tendency to appear to be a shallow anterior chamber and narrow anterior chamber angle.