Early effectiveness of P50 and P200 Ex-PRESS glaucoma drainage device implantation for open angle glaucoma: a randomized controlled study

Background

Ex-PRESS glaucoma drainage device implantations have been clinically applied worldwide.In China, 50 type and 200 type of Ex-PRESS glaucoma drainage devices are used for different types of open angle glaucoma.However, whether the clinical outcomes are similar between 50 type and 200 type of Ex-PRESS glaucoma drainage devices are not elucidated.

Objective

This study was to compare the therapeutic efficacy and security of Ex-PRESS implantation between P50 type and P200 type of Ex-PRESS glaucoma drainage devices for open angle glaucoma

Methods

A randomized, parallel-group trial was designed, and written informed consent was obtained from each patient prior to entering in the cohort.Eighty eyes of 69 patients with various types of open angle glaucoma were included from March 2012 to April 2013 in Wuhan General Hospital of Guangzhou Military Command.The patients were randomized into 2 groups according to randomized digital table.The P50 type Ex-PRESS glaucoma drainage device was implanted in 40 eyes of 35 patients in the P50 group, and P200 type was implanted in 40 eyes of 34 patients in the patients of the P200 group.The disease composition, best corrected visual acuity (BCVA) recovery time, theoretical hospitalization days, lowing intraocular pressure (IOP) range and postoperative complications were compared between the two groups.

Results

The average lowing-IOP ranges of the P50 type group and P200 type group were (21.19±11.22) and (24.35±12.27)mmHg, respectively, with an insignificant difference between them (t=-1.201, P>0.05). The theoretical hospitalization days and BCVA recovery time in the of P50 type group were (3.65±0.92) days and (2.85±0.95)days, and those in the P200 type group were (4.90±0.81) days and (3.40±0.96) days, showing significant decreases in the P50 type group (t=-6.444, P<0.01; t=-2.584, P<0.05). The incidence of postoperative complications were 6.06% and 25.00% in P50 type group and P200 type group, respectively, with a significant difference between the two groups (χ²=9.800, P<0.05).

Conclusions

Although P50 and P200 Ex-PRESS implantation provide a similar effect in lowing IOP, P50 type Ex-PRESS implantation can restore BCVA more rapidly and lessen complications in comparison with P200 type Ex-PRESS implantation in the early postoperative stage.

Glaucoma, open-angle/surgery; Glaucoma drainage implants; Miniaturization; Intraocular pressure; Treatment outcome; Postoperative complications; Ex-PRESS glaucoma drainage device; Randomized controlled study