Soft Custom Lenses for Irregular Astigmatism. Stephanie L. Woo, O.D., F.A.A.O., F.S.L.S. Lake Havasu, Arizona, United States

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1 Soft Custom Lenses for Irregular Astigmatism Stephanie L. Woo, O.D., F.A.A.O., F.S.L.S. Lake Havasu, Arizona, United States

2 Financial Disclosures Consultant to: X-cel Contacts Blanchard Contact Lens Essilor Contacts Visionary Optics Biotissue Basuch and Lomb Alcon

3 What are soft custom lenses? Contact lenses designed for a truly custom fit These designs feature: - smaller and larger diameters - wider range of curvatures - wide range of sphere and cylinder powers - exact cylinder axis - custom lens thickness Custom toric contact lenses correct higher amounts of astigmatism than conventional soft toric lenses. Custom soft multifocals can provide patients with better vision than standard multifocals

4 Current trends Annual Contact Lens update 2012: Many large CL companies discontinued their wider range of parameters (extended sphere and cylinder powers) This left a huge need for soft custom lenses Custom torics offer us an opportunity to manage astigmats in a highly precise way Nichols, J. Contact Lens Update Contact Lens Spectrum. Jan 2012.

5 Custom Soft Torics Recent studies have suggested that astigmats who are new wearers or previous contact lens dropouts achieve visual acuity comparable to spectacles when fitted with toric soft lenses Specialty labs produce custom toric soft lenses with expanded parameters that the larger manufacturers are not currently offering. Dr. Doug Benoit states, These smaller labs have increased what we can do, so more patients are able to wear toric soft contact lenses than in the past. Cole, J. et al. Torics for astigmatism: soft and hard choice. Review of Optometry. July 2013

6 We aren t prescribing enough toric lenses! Toric lens fittings increased from 22 percent to 28 percent from 2000 to 2009 However, on average, 34.8 percent of the world s population has more than 1.00D of astigmatism Therefore, toric lenses are under-utilized worldwide! Eiden, B, et al. Problem solving soft toric contact lenses. Contact Lens Spectrum. Feb 2013

7 Candidates for soft custom lenses High amounts of astigmatism Unhappy with their vision with their current contact lenses Prescription in current CLs is not exact Lens rotation Fit issues Good candidates for GP lenses, but concerned about comfort or unwilling to try Astigmatic presbyopes! Multifocal options are becoming better Irregular corneas

8 Pros and Cons of Soft Custom Lenses Pros of Soft Custom Torics Great vision Great fit No need to build up wear time Stable lens usually does not pop out, even with vigorous activity Truly custom lens Can correct large amounts of astigmatism Gives patients another option who cannot wear GP lenses Cons of Soft Custom Lenses Can be expensive Vision may not be as good as GP lens Lens replacement is usually quarterly/annually Cost of lens if lost/damaged

9 Why soft custom lenses? The universal key to successful contact lens fitting is achieving optimal vision, comfort, and ocular health response. One of the most effective ways to build patient loyalty while developing a contact lens specialty practice is to become proactive in delivering the best vision options for your patients

10 Rumpakis, J. New data on contact lens dropouts: an international perspective. Review of Optometry. Jan 2010

11 How are custom soft lenses designed? Many manufacturers use some sort of fitting nomogram to design the lens Prescribing Nomograms enable practitioners to quickly design custom soft contact lenses for patients with an average corneal diameter or horizontal visible iris diameter (HVID) of 11.6 to 12.0mm.

14 Ordering custom lenses is easy! Many manufacturers only require keratometry values and refraction Giving them Horizontal Visible Iris Diameter (HVID) can assist in providing an even more accurate lens Normal HVID: mm

15 Lens Diameter About 26% of patients fall out of the normal range of iris diameter This could be a reason for contact lens dropout Lens diameter is important for lens stabilization The pressure of the lid-lens interaction causes the lens to move and rotate on the eye. Eiden, B. et al, Problem solving toric contact lenses. Contact Lens Spectrum. Feb 2013

16 Increased lens diameter = increased surface area contact between the lids and the lens, thus reducing lid interaction with the lens edge By increasing the lens diameter, the lid forces cannot generate enough torsional pull to rotate the lens. Eiden, B. et al, Problem solving toric contact lenses. Contact Lens Spectrum. Feb 2013

17 How to measure HVID Use of topographer Measure limbus to limbus using the biometric ruler in topographer s software Measuring at 45 degrees can be useful

18 How to measure HVID Slit lamp reticle Remove an eyepiece from slit lamp and insert reticle Use the slit lamp and integrated reticle to obtain a direct horizontal measurement of the patient s visible iris diameter

19 HVID using Reticle

20 Ordering is EASY! Keratometry Refraction Order!

21 So many ways to order! Call the lab/ telefono /correo electrónico Use online tools/sitio web

24 Other benefits Muy rapido! Quick production and shipping! Customization allows for better vision and fit than standard lenses

25 Other benefits Patients can only order through your office Patient retention Patients know you are on the cutting edge of technology

26 Custom soft lenses for irregular astigmatism YES we have soft lenses available for the irregular cornea!

27 Indications

28 Indications (continued) Intolerant to tradition GP lenses Unable/unwilling to wear scleral lenses Apprehensive patient or new fit

29 Indications (continued) Unilateral Keratoconous Current disposable soft toric wearers Improve quality and stability of vision

30 How it works Mejor optica Courtesy of Mark Andre and Pat Caroline

31 Current designs (list may not be complete) Flexlens ARC, Flexlens keratoconus Kerasoft IC Novacone Soft k Bioperm keratoconus Consise K Continental keratoconus Hydrokone Keracon, Korb K1 and K2 Ocu-Flex K UCL-55 Yamakone IC

32 Realistic expectations Improved comfort compared to corneal GP lenses Vision not as crisp as GP lenses

33 Fitting basics Diagnostic fitting set is usually the best method Each design is fit a bit different, but the fitting guide is included in the fitting set Centration and appropriate touch are important Check for adequate movement and lens rotation

34 Step by step (most brands) Step 1: Choose appropriate base curve Step 2: Assess centration and touch Step 3: Assess rotation Step 4: Over-refraction

35 Step 1: Select base curve Most manufacturers include a fitting guide to help with the initial lens selection X-cel contacts fitting guide example:

36 Step 2: Assess centration and touch Lenses must be centered Lenses touch cornea to create a smooth profile, but don t push too hard similar a lentes de contacto blandas regulares

37 Fitting evaluation of Novakone using NaFl; courtesy of Alden Optical

38 Step 3: Assess rotation Rotation must be very stable for good vision Does the lens rotate when blinking? Does the identifying mark move?

39 Step 4: Over-refraction Custom lenses usually are available in ANY power! Can order exact sphere power, cylinder, and axis! Muy exacta!

40 Order the lens!

41 Fitting tips The flattest lens that achieves a good fit is ideal A lens too steep will result in difficult removal Have the patient wear the lens for a few hours before rechecking their vision

42 Follow up care Quality of vision? Fluctuating vision? Problems with insertion or removal? Lens comfort?

43 Case report

44 Tips on fitting and evaluation After you order custom soft lenses, dispense the lenses in office do NOT let patients take the lenses without checking vision and fit Apply the lenses to the patient or have the patient apply the lenses Pt ed You ve never worn these type of lenses before so they might feel a little strange; that is NORMAL Let settle for 5 minutes

45 Tips on fitting and evaluation After 5 minutes, assess vision OD, OS, OU (distance and near) and check the fit of the lenses If vision is 20/30 or better and the fit is acceptable, dispense the lenses and have the patient follow up in 1-2 weeks. If the vision is not acceptable, check the fit and over-refraction and report results to a consultant

46 Troubleshooting Vision Fit Wear time

47 Troubleshooting Vision If the vision is unacceptable at the dispense, check the fit of the lens the lens may be rotated or move too much If the lens is rotated, but stable, perform an over-refraction and report results to a consultant to re-design the lens If the lens is moving too much, keep everything the same, but make the base curve steeper

48 Troubleshooting Vision: Vision decreases after 3-4 hours or beyond If you see scleral indentation or no lens movement lens is too tight. Reorder with flatter base curve. If you see corneal edema, increase water content to allow for more oxygen. If lens rotates after a few hours, order more prism to make the lens heavier

49 Troubleshooting Replacement Custom lenses are available as a yearly replacement, quarterly replacement, or monthly replacement. Some patients will notice a decrease in vision or comfort when it is time to replace their lenses (lens is wearing out)

50 What is the future of custom lenses? Some companies are now offering custom lenses available in silicone hydrogel material Definitive material: dk is 60; is this enough reason to switch? Very expensive Reproducibility? Current research shows that other factors may play a role in designing custom contact lenses Along with providing keratometry values and HVID, future software from topographers will allow us to measure corneal height (sagittal depth), and scleral angle to create an even more custom fit De Orta-Arellano, F, et al. Measuring Anterior Chamber Angle with OCT.Ophthalmology. 2011

51 Nichols, J. Contact lenses today. Nov 10, 2013

$Clinical Pearls Custom soft lenses provide good vision and an good fit Many manufacturers only require K s and refraction = simple!$

52 Clinical Pearls Custom soft lenses provide good vision and an good fit Many manufacturers only require K s and refraction = simple! Cost can be similar or better than what they are currently wearing Helps more patients successfully wear contacts! Why not give our patients the best lens possible, a truly custom lens!

Fitting Guide. Dallas 800-366-3933 Denver 800-362-4233 Tulsa 800-685-5367

Fitting Guide. Dallas 800-366-3933 Denver 800-362-4233 Tulsa 800-685-5367 Fitting Guide Dallas 800-366-3933 Denver 800-362-4233 Tulsa 800-685-5367 Sagittal Depth Fitting the Jupiter lens design is based upon sagittal depth. Relative sagittal depth is not just the steepness of