Large Pupil Patient Finds Success with Custom Toric Multifocal Contact Lenses

Customized Multifocal Optics During Initial Lens Design Proves Effective

This case study focuses on the design of custom toric multifocal contact lenses for a 50-year-old male patient who wanted to try contacts again. He had worn stock single-vision toric lenses in the past but experienced comfort issues with them. Since the patient was now presbyopic, had previous problems with stock toric lenses, and presented with large pupils, his practitioner recommended that he try custom soft toric multifocal contact lenses.

Keratometry Readings:
OD: 44.25/45.75
OS: 44.00/45.25

Manifest Rx:
OD: -4.75 -1.50 x180 20/20
OS: -6.75 -1.25 x174 20/20
Add: +1.75 OU J1
Pupil Size: 6.5mm in regular room illumination

Using the SpecialEyes Multifocal Simulator and additional images generated by our optical physicist, SpecialEyes designed the trial 54 Toric Multifocal contact lenses with a 3.0mm near-center zone and a 6.0mm peripheral zone.

Initial SpecialEyes 54 Multifocal Trial Lenses:

OD: Base Curve: 8.0 Diameter 14.6 -4.50 -1.25 x180 Add: +1.75
Near-Center Zone: 3.0mm Peripheral Distance Zone: 6.0mm

OS: Base Curve: 8.1 Diameter 14.6 -6.25 -1.00 x174 Add: +1.75
Near-Center Zone: 3.0mm Peripheral Distance Zone: 6.0mm

Simulated Image Interpretation:
The simulated images below allow us to compare the optimized lens design to a standard design. Simulation #1 represents the optimized multifocal design driven by the patient’s pupil size, which called for a 3.0mm near-center zone and 6.0mm peripheral zone. Simulation #2 represents the standard multifocal design, with a 2.0mm near-center zone and 4.0mm peripheral zone. Both simulations were generated using the same basic parameters: a 6.5mm pupil and +1.75 refractive add. As a reminder, the image at the far left represents distance vision, the image at the far right represents near vision, and the images in between represent intermediate vision. Simulation #1, the optimized design, shows improved contrast and a better overall balance of optics at near, intermediate, and distance when compared to the standard design illustrated by Simulation #2.

Simulation #1: 6.5mm pupil | 3.0mm near-center zone | 6.0mm peripheral zone

Simulation #2: 6.5mm pupil | 2.0mm near-center zone | 4.0mm peripheral zone

Visual Acuity at Initial Dispense:
OU: 20/25-
Near OU: J1+

The trial lenses were dispensed to the patient to test in his real-world environment. He returned one week later for evaluation.

Visual Acuity at Follow-Up Visit:
OD: 20/20-
OS: 20/20
Near OU: J1+

Over-Refraction:
OD: -0.25
OS: -0.25

The patient felt the -0.25 over-refraction OU helped to enhance his distance vision while maintaining optimal near vision. His practitioner ordered a new set of trial toric multifocal contact lenses incorporating the over-refraction.
When the patient picked up his new lenses, his practitioner instructed him to wear them for one week and then call the office to report on how he was doing. After using the trial lenses for a week, the patient called and expressed satisfaction with his toric multifocal contact lenses. He stated that he was wearing them on a regular basis and was very happy, so his practitioner ordered a year’s supply of lenses.

Final Outcome: Taking the patient’s large pupils into consideration during the initial lens design proved successful! As shown in the simulations above, increasing both the near-center and peripheral zones across the 6.5mm large pupils during the initial lens design enhanced the performance of the toric multifocal contact lenses and resulted in a successful fit right from the outset.

Would this patient have been successful in a multifocal contact lens design with fixed standard optics? I can’t say for sure, but if the optics were similar to those shown in the standard design above (Simulation #2), then I’d venture to guess he would probably not have been as successful. What are your thoughts? We’d love to hear them. Please submit your comments online.

If you have any questions about this case study or SpecialEyes' 54 Toric Multifocal contact lenses, please feel free to reach out to the SpecialEyes consultation team via phone at 866-822-2020.

Until next time,

The SpecialEyes Consultation Team