To analyze changes of higher-order aberrations (HOAs) after micro-coaxial cataract surgery according to pupil size and to evaluate systemic factors affecting these changes.

Forty-two patients (42 eyes) who had undergone micro-coaxial cataract surgery were followed-up in the present study. HOAs (total RMS, coma, trefoil and spherical aberration) were measured at 1 week, 1 month, 3 months and 6 months post surgery. Differences of HOAs according to pupil size and systemic factors affecting changes of HOAs were analyzed.

Total RMS (1.08 ± 0.89 µm) and spherical aberration (0.03 ± 0.13 µm) were lower in the group with a pupil size between 5.6 and 6.4 mm at 1 month after surgery compared with the group with pupil size lower than 5.5 mm (1.69 ± 0.97 µm, 0.09 ± 0.11 µm) or the group with pupil size larger than 6.5 mm (1.75 ± 0.87 µm, 0.12 ± 0.18 µm), which remained low at 6 months after surgery. Coma and trefoil showed a similar tendency. Patients with diabetes mellitus had smaller pupil size and higher total RMS, coma, trefoil and spherical aberration values at 1 month after surgery compared with patients without diabetes.

HOAs were lowest in patients with pupil size between 5.6 and 6.4 mm after micro-coaxial cataract surgery. Patients with diabetes mellitus tend to have smaller pupil size after micro-coaxial cataract surgery and show higher postoperative HOAs.