The preoperative IOP in the trabeculectomy and MicroShunt-insertion groups were 11.57 ± 1.02 and 12.63 ± 1.34 mmHg (
Figs. 1A and
1B,
n = 10 per group), respectively. In the trabeculectomy group, the postoperative IOPs were 9.07 ± 2.00, 7.63 ± 2.63, 4.73 ± 2.40, 5.73 ± 2.59, 8.10 ± 2.66, 8.07 ± 2.40, 8.27 ± 3.00, and 8.50 ± 3.33 mmHg at one day and 1, 2, 4, 6, 8, 10, and 12 weeks, respectively (
Fig. 1A); in the MicroShunt group, the corresponding IOP values were 9.83 ± 1.81, 8.27 ± 2.82, 6.97 ± 2.44, 8.77 ± 3.50, 9.00 ± 2.84, 9.73 ± 2.35, 10.43 ± 4.01, and 9.67 ± 2.75 mmHg, respectively (
Fig. 1B). In both groups, there were significant differences at all postoperative time points compared to the IOP of the contralateral eye (
Figs. 1A and
1B). Comparing the IOP of the operated eye between the two groups, the preoperative IOP in the trabeculectomy group was slightly lower than that in the MicroShunt group, but there was no statistical difference (
P = 0.0601). The postoperative IOP at four weeks in the trabeculectomy group was significantly lower than that in the MicroShunt group (
P = 0.0407). There were no significant differences in the postoperative IOP between the two groups at other time points. Next, the difference in IOP between the operative eye and contralateral eye (ΔIOP, right eye – left eye) was evaluated. The preoperative ΔIOPs of the trabeculectomy and MicroShunt-insertion groups were 0.10 ± 0.82 and −0.77 ± 1.30 mmHg, respectively (
Fig. 1C). In the trabeculectomy group, the postoperative ΔIOP values at each time point (one day and 1, 2, 4, 6, 8, 10, and 12 weeks) were −3.60 ± 1.19, −5.77 ± 3.37, −8.40 ± 3.02, −7.03 ± 2.47, −5.53 ± 3.37, −4.1 ± 2.57, −4.53 ± 2.86, and −3.70 ± 3.28 mmHg. In the MicroShunt group, the corresponding values were −2.87 ± 1.79, −5.13 ± 3.20, −8.07 ± 2.14, −4.60± 3.42, −4.60 ± 1.99, −4.10± 1.94, −4.17 ± 2.28, and −4.50 ± 1.93 mmHg. There were no significant differences in the ΔIOP between the two groups (
Fig. 1C) at any time point.