What’s New with GPs?

1) New hyper Dk materials

• Acuity 200 (Acuity Polymers): Dk = 200
• Contamac Infinite: Dk = 180

2) New coating advancements

• Tangible Boost for HydraPEG lenses allowing the patient to refresh the surface coating

Oxygen Transmissibility

Which is more important with scleral lenses - lens Dk or tear fluid reservoir? Dr. Walker has found that increasing lens Dk (i.e., from 100-120 to 200) has been most effective.

Wettability

1) Tangible HydraPEG: 90% PEG-based polymer covalently bonded to the contact lens. This is recommended to improve lens wettability and comfort. Any GP lens can be treated with HydraPEG after it has been manufactured.

2) Tangible Boost. Monthly use by patient to replenish the “topcoat” of the HydraPEG surface. It is obtained via a prescription and is available directly to the patient or through the practice.

Material Manufacturers

1) Includes Contamac, Boston, Paragon Vision Sciences, Acuity Polymers, Menicon, Innovision, and LifeStyle. They all typically have a low Dk (<60), moderate Dk (60 – 100), high Dk (100 +), and some have a hyper Dk (150+).

2) Low(er) Dk: These have less oxygen permeability, more rigidity and are less prone to scratches and deposits. They are recommended for rough handlers and heavy depositors

High(er) Dk: Easier to scratch and more deposit prone, they would be recommended for scleral designs, overnight wear (i.e., orthokeratology), and high refractive errors.

SPOTLIGHT ON EDUCATION PART 2:

GP Multifocal Fitting and Problem-Solving

Brooke Messer OD, FAAO

So Why Fit Presbyopes Into Contact Lenses?

1) Amazing Relationships

2) Awesome loyalty to prescriber and office

Patient Communication: Setting Expectations

1) Use words like: balancing the vision demand in the contact lenses, functional vision, freedom from glasses

2) Avoid using: less than perfect, less crisp, glasses will always be better

3) “I want you to be able to do most things, most of the time

Aspheric GP Lenses

1) Good candidates

• Habitual GP wearers with well-centered lenses
• Low-moderate adds but high adds can be successful also
• Active patients will appreciate lens stability
• Small-average pupils

2) Empirical Fitting

• Provide Rx, add, pupil size, HVID, and lid positions
• Zone sizes can be made custom for specific patient measurements
• Lens should be well-centered, alignment with fluorescein, about 1mm movement with the blink, and should move slightly upward with downward gaze

3) Check lens fitting relationship before over-refracting

4) Use your CLMA laboratory consultant on all questions

Translating GP Lenses

1) Great Candidates

• Patients with large pupils
• Visually demanding patients

2) Poor Candidates

• Patients with loose lower lids or tight upper lids
• Patients with low positioned lower eyelids

3) Fitting

• Rests on lower lid in primary gaze and shifts upward – or translates – when dropping eyes to read
• Limited movements on the blink ( < 1mm)
• Prism ballasted and segmented; ideal seg height is at lower pupil margin or just below

Scleral Multifocal Lenses

1) Good Candidates

• Current scleral lens wearers who become presbyopic
• Irregular cornea and post-refractive surgery patients (absence of scarring)
• Dry eye patients

2) Fitting

• There are not typically diagnostic sets so if it is a present scleral lens wearer you can provide specifications, add power, and any other information desired by laboratory
• Otherwise, you can fit a scleral lens as you have with single vision patients
• As scleral lenses tend to decenter slightly inferior-temporally, some designs have decentered optics (i.e., optical center is slightly sup-nasal).
• These are typically center-near designs

The February webinar is kindly sponsored by:

Contamac, Acuity Polymers, and BostonSight

February 15th

Scleral Lens Primer

by Lynette Johns, OD, FAAO, FSLS

March 15th

Enhancing Specialty Lenses Through Performance-Enhancing Drugs

by Mile Brujic, OD, FAAO

April 7th Student Webinar

The Nuts and Bolts of Orthokeratology

by Ariel Cerenzie, OD, FAAO, FSLS

April 19th

Incorporating Technology into Today’s Contact Lens Practice

by Barry Eiden OD, FAAO, FSLS