Before the induction of OHT, baseline IOP was similar between treated and control eyes in all groups (∼15–18 mm Hg, all
P > 0.05).
Figures 1A and
1B show the IOP profiles in the two OHT groups (8 weeks and 16 weeks of IOP elevation, 8wk-OHT and 16wk-OHT) and the two SC groups (the suture was removed at weeks 8 and 12 and assessment was undertaken 4 weeks later, 8wk-SC and 12wk-SC), respectively. As previously shown,
26 a mild IOP spike was evident immediately after suturing (∼40–50 mm Hg) in all groups, that returned to 30 mm Hg by day 3 (
Fig. 1C). IOP was sustained between 25 and 30 mm Hg in sutured eyes throughout the 8 to 16 weeks of the study (
Fig. 1). In the OHT groups, IOP in treated eyes was significantly increased (8wk-OHT: 26.8 ± 0.6 vs. 17.1 ± 0.3 mm Hg,
P < 0.001; 16wk-OHT: 27.4 ± 0.6 vs. 17.0 ± 0.2 mm Hg,
P < 0.001, average of week 2 until the end;
Fig. 1A), as well as in the SC groups (8wk-SC: 26.8 ± 0.6 vs. 17.8 ± 0.3 mm Hg,
P < 0.001; 12wk-SC: 26.2 ± 0.6 vs. 17.1 ± 0.2 mm Hg,
P < 0.001;
Fig. 1B). The magnitude of IOP elevation in treated eyes was comparable between groups (8wk-OHT: 9.7 ± 0.6 mm Hg, 16wk-OHT: 10.4 ± 0.6 mm Hg, 8wk-SC: 9.0 ± 0.5 mm Hg, 12wk-SC: 9.0 ± 0.6 mm Hg,
P < 0.001). Suture removal restored IOP back to levels comparable to control eyes (8wk-SC: 16.0 ± 0.3 vs. 16.9 ± 0.3 mm Hg,
P = 0.08; 12wk-SC: 17.0 ± 0.3 vs. 17.3 ± 0.2 mm Hg,
P = 0.49).