GP lens eye Rounds

PRESBYOPIA: Aspheric Multifocal GP Case

Marsha Malooley OD, FAAO, FSLS

History

• HPI: A 58 year-old white male presented for a contact lens fitting. He previously wore hybrid multifocal lenses but was told to discontinue wear

1. 1. Treated for multiple contact lens acute red eye episodes
   2. Peripheral corneal neovascularization
   3. Denied extended wear but average wear time was 16 hours

• CC: Desires contact lenses that will provide sharp vision at distance, computer, and reading without causing redness or irritation. He is a hospital administrator with high visual demands. “I know I have astigmatism”
• LEE: two months ago with dilation. Records sent from referring ophthalmologist

Examination

• Entering visual acuities with spectacles

OD -3.75 -1.25 x 10, 20/20 Add +2.00D J1
OS -3.50 -1.00 x 165, 20/20 Add +2.00D J1

• Refraction

OD -3.75 -1.50 x 10, 20/20 Add +2.50D J1+
OS -3.50 -1.25 x 165, 20/20 Add +2.50D J1+

• Slit Lamp Examination

• Measurements
  Corneal Tomography

Keratometry: OD 44.2D/45.9D OS 44.7D/46D
HVID: 11.7mm OU; normal lid position 1mm below superior limbus
Pupil size in normal room illumination: 3.5mm OD and OS

Decision-Making Process

• • Amount and orientation of corneal cylinder and refractive cylinder align; gas permeable (GP) lenses would provide sharp consistent astigmatic correction
  • Aspheric multifocal GPs designed for multitude of working distances
  • Patient previously wore GPs prior to hybrids without any red eye episodes
  • Breathability of GP lenses: avoid progression of corneal neovascularization

Fitting and Evaluation

• • Empirically order aspheric GP multifocal lenses based on K’s and Refraction. Fitting guide BCR 0.75D steeper than “K” for patients with 1.25-1.75D corneal cylinder. Add power +0.50D greater than spectacle add
    OD BCR: 7.50mm/-4.50D; add +3.00D/OAD: 9.5mm
    OS BCR: 7.41mm/-4.50D; add +3.00D/OAD: 9.5mm
  • Both lenses were lid attached and centered well over the pupil. With fluorescein application there was central alignment with moderate peripheral clearance. There was slight translation of both lenses in down gaze. Vision was tested in normal room illumination. Binocular vision at distance 20/20 and J1 at near with difficulty.
  • Two-week follow-up visit: Good comfort and patient was pleased with distance vision but near vision is slightly strained. An over-refraction was performed binocularly with +0.25D acceptance OD at both distance and near making reading easier. The right lens was reordered with power adjustment and exchanged without an appointment
  • One-month follow-up visit: Overall the patient was happy with vision and comfort. He occasionally wears +1.50D readers over his contact lenses when tired or when the lighting is poor. Neovascularization is stable OU. He denied redness or irritation.

Clinical Pearls

• • Push plus power when over-refracting multifocal lenses at distance as it will help with near vision
  • GP lenses correct corneal astigmatism and provide sharper vision when fitting multifocals in presbyopic patients
  • Aspheric GP multifocals are good for a range of focal distances including computer

Useful Resources

1. 1. Ortiz-Toquero S, Martin M, Rodriquez G, de Juan V, Martin R. Success of Rigid Gas Permeable Contact Lens Fitting. Eye Contact Lens 2017;43(3)168-173.
   2. Sicks L. Bringing Clarity to CLARE. Review Cornea Contact Lenses. April, 2015:16-19.
   3. Bennett ES Henry VA. Bifocal Contact Lenses, In Clinical Manual of Contact Lenses (3rd ed). Philadelphia, Wolters Kluwer/Lippincott Williams and Wilkins, 2009:371-409.
   4. Watanabe R. Contact Lens Design & Materials: Modern GP Multifocal Lens Designs. Contact Lens Spectrum. 2010;25(10).
   5. Bennett E. Innovations in gas permeable multifocal contact lenses. Clin Optom 2010;(2)85-90.