To determine the mean Higher Order Aberration (HOA) and its third and fourth orders in a normal young adult myopic population.

Mild to moderate myopic patients (age range: 18-35 years) referred to the Khatam Eye Hospital were entered in an observational cross-sectional study. Patients with history of any intraocular, corneal, or keratorefractive surgery, contact lens use, any corneal anomaly, and hyperopic refraction > +0.50 diopters (D), myopic refraction > -6.00 D or cylindrical refraction > 2.00 D were excluded. All measurements were done by an experienced optometrist using Hartman-Schack aberrometry (ZyWave aberrometer - Bausch & Lomb, Rochester, NY). The aberrations were expressed as RMS, representing the root mean square of the wavefront errors, measured in micrometers. All RMS values were calculated and reported across an entrance pupil of6 mm. Enantiomorphism was neutralized by inverting the sign of mirror-symmetric coefficients of left eyes.

A total of 73 cases (68.49% female) were evaluated, with a mean age of 25.43 ± 5.23 years (18–35 years). HOA in 6mm was 0.312±0.012, HOA without Z400 was 0.303±0.012, vertical trefoil was 0.089±0.015, horizontal trefoil was -0.003±0.013, vertical coma was -0.064±0.021, horizontal coma was -0.035±0.013, quadrifoil z440 was -0.006±0.005, and spherical aberration was 0.028±0.016. There was a much similarity in aberrometry values in both eyes.

Aberrometry helps the ophthalmologists to have a better explanation for the visual function of the patients. The obtained normal values will be helpful in pre-operation patient evaluation for refractive and intraocular surgeries, mostly in corneal involving surgeries.