Visual acuity and contrast sensitivity comparison between Tecnis and AcrySof SA60AT intraocular lenses: A multicenter...

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Optics

Background:

• Cataract surgery often involves intraocular lens (IOL) implantation to restore vision.
• Corneal spherical aberration can impact visual quality after cataract surgery.
• Aspheric IOL designs aim to mitigate visual aberrations compared to conventional spherical IOLs.

Purpose of the Study:

• To compare the visual performance of an aspheric IOL (Tecnis Z9000) with a conventional IOL (AcrySof SA60AT).
• To evaluate best corrected visual acuity (BCVA) and contrast sensitivity under photopic and mesopic conditions.

Main Methods:

• A prospective, randomized, masked study involving 60 patients (30 eyes per IOL type) across three surgical centers.
• Visual acuity measured using the Early Treatment Diabetic Retinopathy Study chart.
• Contrast sensitivity assessed using sinusoidal grating charts at photopic (85 cd/m²) and mesopic (6 cd/m²) luminance levels for spatial frequencies from 1.5 to 18 cycles per degree.

Main Results:

• The aspheric Tecnis IOL group achieved significantly better mean BCVA (-0.053 logMAR) than the conventional AcrySof IOL group (0.006 logMAR).
• Superior contrast sensitivity was observed with the aspheric IOL at spatial frequencies of 3, 6, 12, and 18 cycles per degree under both photopic and mesopic conditions.
• Peak contrast sensitivity improvement with the aspheric IOL was 36% (photopic) and 54% (mesopic) at 18 cycles per degree.

Conclusions:

• The aspheric Tecnis IOL provides superior BCVA and distance contrast sensitivity compared to the conventional AcrySof IOL.
• The observed differences are clinically significant, particularly at higher spatial frequencies.
• Findings suggest potential benefits of aspheric IOLs for visual function in pseudophakic patients.