Custom Multifocal Optics are a Success for Patient with Smaller Pupils

A practitioner called to design a pair of the custom SpecialEyes 54 Multifocal Toric contact lenses for a hyperopic astigmatic patient. The practitioner provided HVID, Keratometry (K) readings, manifest refraction, and pupil size to the SpecialEyes consultant, who utilized the SpecialEyes Arc Length Contact Lens Calculator to design the base curve and diameter of the lenses and the SpecialEyes Multifocal Simulator to design the custom multifocal optics.

Patient measurements were as follows:

HVID
OD: 11.8mm
OS: 11.8mm

Keratometry Readings
OD: 43.75/44.00
OS: 44.50/45.50

Manifest Refraction
OD: +2.00 -1.00 x125
OS: +1.25 -1.25 x070

Pupil Size (regular room illumination)
OU: 3.3mm

The initial trial contact lens parameters were as follows:

SpecialEyes 54 Multifocal Toric
OD: 8.1/14.6 +2.00 -1.00 x125 +1.75 add
OS: 8.0/14.5 +1.25 -1.25 x070 +1.75 add

Multifocal Optics: 1.8mm near center zone and 3.0mm peripheral zone

Upon initial trial lens evaluation and dispense, the lenses were centered, fitting well, and exhibited optimal movement on blink. The right lens was rotated 8 degrees clockwise, but was stable and not fluctuating. The left lens was rotated 10 degrees counterclockwise and was also very stable.

Visual acuities with the trial lenses:
OD: 20/30 @ distance and 20/60 @ near
OS: 20/25 @ distance and 20/25 @ near

Action: Since the lens rotation was very stable, LARS (Left Add, Right Subtract) was implemented to account for the rotation in hopes to improve distance visual acuity. Since the patient was seeing worse at near in the right lens (20/60), it was decided to alter the multifocal optics to improve near vision. The near center zone in the right lens was increased from 1.8mm to 2.0mm in hopes to improve near visual acuity for the patient. Since the patient was seeing fairly well at near via the left lens (20/25), no change was made to the near center zone in that lens. The thought was once the lens rotation is compensated for, both near and distance would improve.

The parameters for the second pair of trial contact lenses were as follows (changes in bold):

OD: 8.1/14.6 +2.00 -1.00 x133 +1.75 add
Multifocal Optics: 2.0mm near center zone and 3.0mm peripheral zone

OS: 8.0/14.5 +1.25 -1.25 x060 +1.75 add
Multifocal optics: 1.8mm near center zone and 3.0mm peripheral zone

The new trial lenses were dispensed and the patient wore the lenses for an adaptation period. At follow up, the patient expressed satisfaction with the new trial multifocal toric contact lenses and an annual supply of lenses was ordered.

To learn more about designing and prescribing the custom soft SpecialEyes 54 Multifocal Toric contact lens, please sign up for Dr. Rob Davis’ email course. Or, submit your online request and our team would be glad to send you information and pricing.

Happy Fitting,
The SpecialEyes Consultation Team

 

 

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