Comparison of visual quality between aspheric and spherical IOLs

Area of Science:

• Ophthalmology
• Optics
• Biomedical Engineering

Background:

• Cataract surgery involves replacing the clouded natural lens with an artificial intraocular lens (IOL).
• IOLs can be spherical or aspheric, with aspheric designs aiming to reduce optical aberrations.
• Postoperative visual quality is influenced by ocular aberrations and contrast sensitivity.

Purpose of the Study:

• To compare the degree of postoperative ocular aberrations and contrast sensitivity between aspheric and spherical intraocular lens (IOL) implantation.
• To evaluate the visual performance outcomes of aspheric versus spherical IOLs in cataract surgery.

Main Methods:

• A randomized prospective comparative study involving 60 eyes of 30 cataract surgery patients.
• Patients received a spherical IOL in one eye and an aspheric IOL in the contralateral eye.
• Ocular wavefront higher-order aberrations (HOAs) and contrast sensitivity were assessed 1 month postoperatively.

Main Results:

• Aspheric IOLs resulted in significantly lower total HOAs (median 0.26 RMS) compared to spherical IOLs (median 0.34 RMS; p<0.05).
• Contrast sensitivity was significantly better with aspheric IOLs (median 1.8 log units) than with spherical IOLs (median 1.65 log units; p<0.05).

Conclusions:

• Aspheric IOLs significantly reduce higher-order aberrations (HOAs) compared to structurally similar spherical IOLs.
• Aspheric IOL implantation yields better contrast sensitivity under photopic conditions.
• Aspheric IOLs offer improved visual quality outcomes in cataract surgery.