The analysis of postoperative intraocular pressure elevation after pars plana vitrectomy with perfluoropropane gas

Objective To analyze postoperative intraocular pressure elevation after pars plana vitrectomy with perfluoropropane gas by using ultrasound biomicroscopy(UBM).Methods Pars plana vitrectomy with perfluoropropane gas was performed on 69 eyes of 66 patients with retinal detachment.The preoperative and postoperative intraocular pressure,UBM imaging of anterior segment were analyzed.Results The intraocular pressure increased from a mean preoperative value of(13.07±4.41)mmHg to a mean postoperative value of(27.96±11.55)mmHg on the first postoperative day.About 47.83% had elevated,intraocular pressure ≥25mmHg.There is statistically significant between preoperative and postoperative in the eyes of ocular hypertension.Between ocular hypertension and normal intraocular pressure,there were statistically significant in ACD,ACA,TCPD,AOD500 and SCPA in postoperative and of ACD,ACA and AOD500 in preoperative.57 eyes were followed-up from 2 to 4 months.In 30 eyes of ocular hypertension,intraocular pressure was normal and the anterior segment has no significant compared to preoperative.Conclusion The complications associated with the use of C_3F_8 probably are related more to its expansile properties.Expanding gas pushes the iris-lens diaphragm forward.Shallower anterior chamber,narrower angle,forward rotation of the ciliary body and inflammatory exudate may explain the intraocular pressure increase in these eyes.So the function of anterior chamber angle and the compensation to high intraocular pressure has definite effects on postoperative ocular tension.