Purpose <p>We investigated changes in corneal higher-order aberrations (HOAs) after iStent inject® W implantation combined with cataract surgery.</p> Study design <p>Retrospective observational study.</p> Methods <p>A total of 41 eyes that underwent this procedure between August 2022 and July 2024 were included. Intraocular pressure (IOP), corneal HOAs, coma-like aberrations, and spherical-like aberrations were measured before and at 1, 2, and 3 months after the surgery. A mixed-effects model was used for statistical analysis.</p> Results <p>Mean IOP significantly decreased from 14.7 ± 2.9 mmHg before surgery to 13.5 ± 2.9 mmHg (<i>P</i> = 0.002) at 1 month, 13.0 ± 2.4 mmHg (<i>P</i> &lt; 0.0001) at 2 months, and 12.9 ± 2.8 mmHg (<i>P</i> &lt; 0.0001) at 3 months after surgery. The mean corneal HOAs was 0.221 ± 0.136 μm preoperatively, and this was not significantly different compared with those postoperatively (0.208 ± 0.100 μm at 1 month, 0.222 ± 0.134 μm at 2 months, and 0.236 ± 0.176 μm at 3 months postoperatively). Similarly, the mean coma-like aberration (0.205 ± 0.132 μm) and the mean spherical-like aberration (0.080 ± 0.043 μm) preoperatively did not significantly change postoperatively.</p> Conclusion <p>Following iStent inject W implantation IOP is reduced whereas, corneal HOAs remain stable for up to 3 months.</p>