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Ocular Surface Characteristics of the Asian Eye
Meeting Synopsis
Academy 2010
pective Analysis of Risk Factors Associated With Contact Lens Induced Inflammatory Events During Continuous Wear
Feature Review
Adequate tear mixing under a soft contact lens may play an important role in minimizing certain > more
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Questions and Answers
A list of Questions and Answers have been answered by our panel of experts.

Archived Questions and Answers

It is difficult to get an objective answer about lens solutions, because all reps obviously recommend their products. I would appreciate your opinion on the lens solution that show least staining patterns with respect to silicone hydrogel lenses or conversely which show the most?


Approximately two weeks ago I saw a -7.00D myope who has no complaints with wearing the Biomedics 55 daily wear except for the following situation, which is quite bothersome to him. Occasionally when he wants to wear his glasses for the day, his vision will be normal in the morning with his glasses, but throughout the day it will worsen, to the point that he says he has difficulty driving home, and states that his vision is 50% worse than in the morning. This only happens with glasses, never with contact lenses. He denies any dryness, irritation, or any other symptom, and is adamant that he does not sleep in his contacts. The fit of the contacts was good, and I could detect no adverse effects of him wearing the lenses. I was at a loss to explain the cause of this. I recommended that he switch to PureVision to increase oxygen, and see if his problem occurs again. However, I don't believe that possible corneal edema can completely explain his situation for a variety of reasons. Have you ever heard of this occuring? Any insights into why this may be happening and what you would suggest to do if the patient states at the followup that the blurred vision is still occuring, would be very much appreciated. Thank you for your time.


In the issue of SiH and materials and solution useage can you tell me what the care solution and lens relationship performs in view of toxic response and which solution performs the best. also can you tell me what current incidence of MK is for DW SiH v EW SiH v daily wear soft and incidence male vs female


I recently fitted a patient with Focus Night and Day as daily wear only and when he came back for the follow-up, there was a significant amount of film on both contact lenses. He was using the Clear Care soln (hydrogen peroxide based). Is there any correlation with the contact lens and the solution? Or is there another reason for the film? Also, which contact lens solutions do you recommend for silicone hydrogel lenses?

5. What is more important ? : the Dk/e of a contact lens or the E.O.P of this one ? Some hydrogels lenses have a E.O.P very near than Silicone-Hydrogels ! The E.O.P is measured "in vivo" and the transmissibility is measured in laboratory : What value is more important for the oxygenation of the eye ?


I have a 45yo female Px recently referred for opinion. She was changed from DW 55% lenses into 02 Optix on DW. After 2 days wear she presented with: 1 Pain, photophobia and lacrimation in the LE only. 2 Slit lamp: R clear (NAD) L mild epithelial grade 1 diffuse SPK, gross anterior stromal oedema, marked endothelial fine brownish granular KP and a loss of definition of endothelial cellular outline. Grade 1 cells and flare in AC. 2 IOP R&L 10mm Hg 3 CCT R 575 um, L 685um I suspect a unilateral case of a form of endothelial dysfunction, due to the contrasting appearance between the endothelium of the R and l eyes. However, I am a loss as to how to explain the marked inflammatory response of the AC and the corneal oedema. Are SiH lenses poor at water transfer? Would the difference in water transfer and electrolytes between a 55% material and the Sih cause a Ph shift that could cause a sub-optimal endothelium to cause the oedema response and by externsion the AC reaction? Or are the two non-related?


I saw a 42 y.o. pt. the other day who has been wearing Nite and Day lenses for over 2 years now. During the exam, I noticed with slit lamp the appearance of fine, small, bubble-like epithelial opacities on both corneas. They stained with fluoroscein. Most stained with a solid appearance, while some stained in just a ring pattern with no stain centrally. The corneas did not appear edematous and the k's were almost unchanged from this exam to the last. He was wearing an 8.4 and currently I have him in an 8.6. Any ideas as to what I might be seeing? Thanks.


Are there any studies which relate the quality of the tearfilm and wearing silicone hydrogels. I fit silicone hydrogels for ew or dailywear since two years. Some of my patients with "dry eye sympthomatics" prefer wearing silicone hydrogels than wearing their benzg5x or proclears (around 60%).Around 40% don't like silicone hydrogels at all. They describe a blurry, foggy vision and a dryer eye and more foreign body feeling. Generally less comfort. I wonder, if I can separate these two groups already at the first examination by concentrating on their tearfilm. What I do know, is that the quantity of tears (under normal phys. circ.) does not really allow to separate these two groups. After my experience the more lipids or proteins in a tearfilm, that less they like to wear silicone hyd. (even if I change from a all in one solution to a peroxyde system)? Is/ Are there clinical studies with this topic?


Do silicon hydrogels cut out all harmful UV rays?


I have a 60 year old white male patient who has been wearing fnd OS only (monovision) for one year. He had no visual or ocular complaints. He did admit to poor replacement of the lens: he would wear it EW x 30 days, clean it overnight, then rewear x 30 days EW. At his annual exam, the bcva OS was reduced to 20/40 with an increase in minus of about -0.75 diopters. The lens appeared cleaned and fit well. After d/c lens wear x 1 week, bcva OS returned to 20/20 with the same Rx as the year before. Is corneal edema a likely cause? Could this patient resume fnd wear with proper replacement? He had great difficulty i & r lens, and prefers EW. Should he be refit with a lower modulus lens, such as Purevision?


What do you think about Acuvue Advance and the newer Acuvue Oasys? They seem to have relatively high dk/t stats but perhaps without as much stiffness as Pure Vision or Night and Day. The stats I saw were: traditional Acuvues dk/t: 28, Acuvue Advance: 60, Acuvue Oasys: 103, Pure Vision: 101, and Night and Day: 140+. What I'm wondering is: what's the tradeoff between the problems of low oxygen permeability vs. extra material stiffness, especially for someone who will use any of the lenses as daily wear rather than extended wear.


I have a patient with glaucoma using Xalatan. He wears +6.00 N+D 84 extended wear, as he is elderly and can't do insertion and removal, which I do monthly in office. His ophthal has been reviewing the glaucoma which up till now has been stable. Most recently, the pressure is up in one eye. We are going to try an 86 BC to give more movement and improve tear exchange, but the opthal asked re drug penetrance in a SiH contact lens. Is there any specific literature I can print out for him ?


What causes Mucin Balls? is it due to extended wear? if so, why wasn't it reported in the earlier days when people used HEMA as continuous wear lens modality?


I would like to know if lens coatings on silicon hydrogel lenses are essential in producing properties specific to this type of lens i.e. are they implicated in the manufacture of a specific type of silicon hydrogel lens, or are they just coatings used similar to coatings on other soft hydrogel lenses.


I've got a few patients wearing acuvue advance. I discovered that their bulbar redness is of a higher grade compared to them wearing purevision. Why does acuvue advance cause more bulbar redness, is it due to the lens design of acuvue advance? My patient do not sleep with lenses on... And comparing Acuvue Advance & Purevision, why is it that the LIMBAL redness of Av Advance is more significant than Purevision? I find it weird because their oxygen flux is just a 1% difference. And do you have the lens design of both Acuvue Advance & Purevision? I've been searching for it but up till now i'm still unable to find them.


A cautious patient recently asked if there were any similarities between the silicone hydrogel contact lens material and silicone used in breast implants. Given the possible health problems associated with implants in the past she was concerned about any related issues. What can I tell my patient to reassure her?


I'm an ophthalmologist and I seem to have more patients with contact lens "irritation", redness, blurred vision with the silicone hydrogels. I would tend to think about overwear and abuse, however, I've had the same experience with my own eyes. Coincidence? Reality? Doesn't seem logical.

18. I have a question regarding your editorial Expect the Unexpected. In this editorial you use two expressions: hyperopic shifts and myopic reductions. Do they mean the same or different.


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