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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
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Archived Qs & As | Would you like to submit a question? > click
I have a patient who has been wearing Night and Day lenses for 3 months (+4.00). At her last aftercare I discovered that she had suffered an intracorneal haemorrhage on removal of her lens. She has some slight vessel infiltration and suffers from HBP. I sent her to an Ophthalmologist who said she should not wear any CL's for 2/52 but did not want to see her back again! I have now reviewed the situation 2 weeks later and the haemorrhage is slowly resolving but looks like it will leave an opacity. Should I continue with CW and how long is it likely to take for it to resolve completely? I understand it will leave a scar but fortunately is not close to the visual axis so isn't likely to cause a problem with VA. answer
Since the silicone hydrogels have thicker edges, does this increase the rate of GPC, and more importantly, can the patients arrive sooner at the "exhaustion syndrome", where they no longer tolerate contact lens wear? answer
What is the youngest age that you feel you could ethically fit a patient with cosmetic 30 day wear silicone Hydrogels?

I had a request today from a 12 year old (accompanied by her mother). She presently wears one day disposables successfully but finds insertion a bit of a problem first thing in the morning.

Apparently a school mate of hers already has them! answer

I would like to know if there is any study between hydrogel CL and silicone hydrogel for patients with dry eye. answer
I would like to know where I go to find a 'handy' chart that shows different stages of GPC to have in th exam room in order to educate patients about GPC? I am looking for a color photo series with the different stages illustrated. Something 8" X 11" or smaller.
".....a picture is worth 1,000 words...." answer
With the flatter base curve N&D I noticed that the lenses seemed to have a tendency to loosen or become flatter after a few days of wear. I though this might have been because the front surface of the lenses became dryer. Because the posterior surface of the lenses remained in contact with the eye, it would stay wetter and the lenses would tend to be pulled away from the front surface only causing it to flatten. I have also noticed that the steeper lens does not have that tendency. I believe that because the material is more rigid than conventional soft lenses, the steeper anterior surface has a harder time to be pulled away from the cornea. Could you comment on this. answer
Just wanting to know what the experience has been using Ciba N/D's in a piggy-back system for the more sensitive keratoconics that don't tolerate RGP's very well. Which lens is best used on the eye first, the soft or the hard? answer
I have a patient who is now some 8 months pregnant and has been wearing Night and day lenses for some 18 months now. She is -7.00 and is keen to wear her lenses during childbirth to enable her to see the new baby when it arrives. Should I advise her to wear the lenses or to remove them during child birth? answer
Silicone hydrogel extended lenses can cause keratitis etc, which can be caused by non-EW as well. Are there any effects that are UNIQUE to silicone hydrogel? answer

What is your opinion on fitting a patient with silicone hydrogels for continuous wear if the patient is diabetic due to obesity and is not on any medication but is assessed regularly by his/her doctor? answer


Which cleaning regimen(s) do you recommend for silicone hydrogels, and which regimens, if any, are contra-indicated? answer


A patient is very pleased with N&D. White eyes, 8.40 better than 8.60 in contralateral trial and Rx -8.00 -6.50 R&L. Previous history low grade hypoxia with Focus and better with Dailies 7/7. Some Focus sols toxicity. N&D most comfortable etc etc no stain brilliant... Except they gum up between lens and eye with deposits nocte. Clear by morning and only way to see clearly in evening is to remove and clean (Opti-free express seems OK with no apparent allergic response). She loves the lenses, so do I, from her hypoxic history and D/W is obviously on at some cost but do you have any ideas. The deposits are greasy/oily, brownish under SL and stringy not mucin balls and no epithelial indentation, they disappear when lens is removed. Doesn't seem to need a rub just drop into sol, muck floats off and re-insert. Bit of a loss mate! answer


I have been wearing both the PureVision lens and the Night and Day lens to test them for myself. The Purevision is comfortable after cleaning, but the Night and Day lens is less comfortable. The Night and Day lens wears beautifully as a continuous wear lens, but, once it is cleaned apparently loses some comfort. Is there a reason behind this? answer

I have a 29 y.o. breast-feeding female trying the PureVision lenses. She had an episode of solution sensitivity induced keratitis about 18/12 ago but that has resolved and she has returned to normal daily lens wear (extreme h20)for the past year or so. After the first overnight wear, everthing seemed fine at the 'morning - after' review. However, during the second DAY of wear, she noticed the lenses were dirty and she needed to remove them, clean and reinsert. My examination revealed some type of deposits on the lenses. A rub and rinse removes them but she will notice the 'blur' from the deposits within six hours of wear again. This does not happen with her extreme h20 lenses. What is the cause of this? Her Rx is R & L -2.50 DS. answer

I have found the Ciba Nite and Day cl to be useful in managing patients with dry eye (used on a daily basis). Is cleaning i.e. Rub and rinse, with a one step solution recommended on these particular lenses? answer


In Dumbleton's editorial as well as the Optician article by Guillon and Maissa a distinction is made between rigidity and elasticity. My dictionary defines elasticity as flexibility and rigidity is lack of flexibility. Please explain the differences as applied to the properties of silicone hydrogels. answer


I fitted a patient with silicone hydogels recently. No problem at 24 hour visit. At 1 week visit patient was happy but I noted distinct SEALs in both eyes. Still noticable 24 hours later after removing lenses. I have discontinued her wear with this mode of lenses and returned to daily disposables for occasional wear. Patient was disappointed. Did I have any option? answer


What is the percentage of discontinuation due to SEAL and CLPC respectively? answer


Could switching brands of Silicone Hydrogel lenses avoid or reduce the recurrence of the above reactions? answer


Do you recommend refitting DW patients who have had inflammatory events such as IK, AIK or AI into CW? Would they be at greater risk for developing CLARE or CLPU? answer


Are there any topographical changes in the cornea with a well fitting silicone hydrogel lens? answer


Since the silicone hydrogel lenses are stiffer than a normal hydrogel how much astigmatism can be "masked" clinically with the focus day/night lens? answer


How often would you expect to see microcysts in the cornea of silicone hydrogel extended wear patients? answer


How do silicone hydrogels overcome the potential to be hydrophobic? answer


Do you recommend a daily flush of the eyes when using CW lenses? If necessary, what would you recommend flushing with? answer


I am a solo practice optometrist of 30 years with a moderate size contact lens practice. I have found success in reducing complication incidence with disposable soft lenses by emphasising the necessity for clean lenses and providing information on supplemental cleaning for those patients who will not be compliant with recommended disposable schedules. Due to the cost of silicone hydrogels I am having a problem compliance with monthly disposable schedule resulting in corneal complications assoiciated with soiled lenses. Is it possible to extend the lifespan of silicone hydrogels with supplemental cleaning? answer


What are mucin balls and are they of clinical significance? answer


Why should you not use low Dk/t soft contact lenses for extended wear. answer


Does continuous wear of silicone hydrogel lenses result in physiological changes? answer


Is continuous wear with silicone hydrogel lenses a viable alternative to refractive surgery? answer


Is there a difference between continuous wear and extended wear? answer


How much overnight corneal swelling do silicone hydrogel lenses produce? answer


What sort of adverse events occur with silicone hydogel lenses? answer


Because of greater price for CW lenses compared to DW to the patient, what would you suggest to a regular practice on how to approach patient with these type of lenses without having the usual "It's way too expensive" type of reaction from patient? answer


Is high molecular weight fluorescein necessary for testing with the lens on the eye, or do silicone hydrogel lenses not take up stain in the same way as HEMA lenses do? answer


Could you elaborate on the push up test, or give me an online reference? answer


What is the incidence of SEALS, microbial keratitis and CLPU with silicone hydrogels? answer
Since the recent article by Dr. Kathyrn Dumbleton affirmed what I expected, that silicone hydrogels may work better than other CLs for patient's with chronic dry eye problems, especially in a daily wear mode, how often should the lenses be disposed, if cleaned and worn as DW lenses? answer
Would you please give me a comment on these: 1)Some SiH wearers feel more initial discomfort (upon insertion) compared to hydrogel lenses. Is it only because of increased modulus of the material or also influenced by edge design and thickness ? answer


I'm a clinician, and I have a question you might be able to help me with. We have a case where we for various reasons would like to fit a contact lens for continous wear, and the choice of course will be the silicone hydrogel material. But the patient is using eyedrops for glaucoma on a daily basis. I know that you normally expect a soft contact lens to enhance the effect of an eyedrop-based medication, but given the less amount of water in silicone hydrogels, would it be acceptable to wear a contact lens while using glaucoma eyedrops? answer
How does one differenciate between the appearance and staining patterns of microcysts versus mucin balls? answer
What initial schedule of consultations would you recommend for a new fit of silicone hydrogel EW? At the moment, I check the lenses on Day 0 (initial fitting), Day 1, 3 weeks (prior to ordering), and then every six months (before re-ordering). Also, would you recommend any particular checks be made that would not be part of a conventional DW CL aftercare visit? Thanks. answer

I have been fitting silicone-hydrogels (Purevision and Night and Day) for 5 years. Most of my px's wear them as 1 month extended wear. In this population, I have found many cases of peripheral infiltrates that may or may not have been sterile (I can't recall a single case in the daily wear population). Not all are symptomatic when I see them (ie. some are noted at routine follow-up), but when there are symptoms, the px invariably suggests that the problem started when "I got something in my eye". This almost universal description by px's suggests to me that the px may be correct. I believe that these inflammatory reactions, which may eventually lead to MK, are initiated by temporary insufficient replacement of the precorneal tear film under the CL. In practice, fitters may feel safe in fitting these lenses steeper than other CL's and certainly a Night and Day lens fit too flat is sure to cause lid awareness. However, the steeper fit may not allow adequate tear film renewal. I'm now considering recommending a non-preserved saline drop used BID for all S-H EW contact lens wearers. Is there any research to bolster my clinical impression?


Following from the BCLA in 2004 there was suggested issues with the use of lens care solutions and silicon hydrogels. Indeed with Acuvue Advance certain sols are being strongly advised not to be used. Is there are new clinical evidence / publication which has looked at these new generation materials vs any new / existing solutions on the market?


We have used the CIBA Night & Day lens very successfully in many patients, and it is the first lens I feel comfortable suggesting overnight wear to patients.  We have had three patients this year, however, who have come in (all three were new patients) with signs of hypoxia secondary to soft CL overwear.  After refitting these three in the Night & Day, the cornea has decompensated to varying degrees.  The most severe case was in a 60 yr old moderate hyperope who had been wearing her previous non-disposable lenses on an extended-wear basis for over a year.  Her corneae developed obvious edema, striae and bleb-like opacities on the endothelium.  This slowly resolved after discontinuing the lenses.  We have resumed daily wear in an Acuvue 2, and the problem is continuing to resolve.  The other two patients exhibited milder signs, but that may have been because we were aware of the problem and stopped the overnight wear.  We consulted our corneal specialist at the school, and he could not come up with a good reason the cornea would break down in the presence of more oxygen.  It did not seem like an allergic reaction.  I was wondering if any of you have come across this apparently atypical reaction. 


I have a 15 year old patient who plays competitive water polo and spends nearly every day wearing contact lenses in a chlorinated swimming pool. Although I recommended swimmng goggles he prefers not wearing any, and he and his coach were wondering what contact lens material would minimize chlorine uptake. He has been wearing Acuvue 2 contact lenses, and I am having him try Acuvue Advance contact lenses. Would the chlorine uptake in water, and from chlorine gas above the water, be any different in Acuvue Advance or another silicone hydrogel than a HEMA contact lens?


An existing extended wear px of mine has just been diagnosed as diabetic ,this px is 30 yrs old. I would normally not fit diabetics with extended wear contact lenses, however this px has been told by the hospital that they are still fine for him. Please advise me of your opinions on this.


After having successfully fit well over 300 patients in silicone hydrogels since mid January I have noticed that mucin ball formation is rarely seen in my daily wear patients(ava) and often seen in extended wear (fnd). Is this due to extended wear or higher amounts of silicone? Also many patients with focus night and day (fnd) seem to need longer trial periods to decide if they like the lens(most of whom do). Is that because their corneas are still going through rehab? Next I have had about 8 to 10 acuvue adv. pts. switch back to previous lenses after a couple months any ideas? most of them just said comfort decreased after a few pair. thank you for your time. ps I am getting Better than 90% success with silicone hydrogel lenses.


I would like to thank Dr J Smythe for her interesting article on the Piggy back solution I have many patients that have been hacked by refractive Surgery and are always a challenge to refit with contact lenses 3 questions can you use this system on patients who have undergone RK and lasik in the same eye is neovascularization a sight threating risk for post op RK patients using soft contact lenses could you please explain more specifically the method for selecting base curve of the rigid contact lens for the piggy back system. answer

Will a silicone lens used as a bandage lens for epithelial erosion cause less erosion than a regular hydrogel? I had a late 50's patient erode after about 1 month. Vision started to decrease. Left lens out for two- three days and surface reepithialized. Put lens back in and patient saw great. Corneal surface is irregular and patient sees better with a bandage lens in left eye with glasses over the top than with just plain glasses. Patient has eroded before. VA with glasses 20/40 -20/70. with contact 20/25 to 20/40 always better with contact. answer
I found those patients who removed the SH contact lenses frequently, complained of hazy vison,biomicroscopy show greasy films on the surface,should we reccomend to wear on as continous wear with minimun removal . answer
Is there any link between CLPU formation and oxygen transmission through contact lenses, ie. are you more likely to get a CLPU wearing lenses which transmit lower levels of oxygen? answer
I am an optometrist in New Jersey and have been fitting silicone hydrogels for the past 2 years extensively. I have recently come upon a few patients whereby I have noticed a significant drop (between 3-5 mm ) in IOP after wearing these lenses. The patients had all been either wearing conventional DW or Acuvue lenses as EW. I don't normally measure IOP's on follow ups but noticed first with a patient I had targeted as a glaucoma suspect with pressures running 20-22 mm. He was refit from Acuvue EW to Focus Day/Night and I measured a 5 mm drop in both eyes. I have been now looking for it and found 3 more patients with similar phenomena. My theory is that with silicone hydrogels we are getting a truer measurement since cornea thickness is more normal (or thinner that what is was with other lower DK materials). Have you seen similar phenomena? What do you think? answer

I know that use of fluorscein is ok with SH lenses. Does the surface treatment on these lenses have any affect on their absorbtive properties, i.e., use of ocular med's for treatment of glaucoma? Are they any less likely to absorb pharmeceutical drops than conventional hydrogel lenses? answer

55. Can the preservatives sorbic acid and EDTA (ingredients of Clerz rewetting drops) damage the lens surface of Night&Day contact lenses? answer

Could the panel please tell me the current research rate for microbial keratitis for the following modalities?

a) daily wear monthly disposable
b) continuous wear monthly disposable
c) daily wear contact lens answer


Which is the pore size of Focus N-Day and Purevison ? answer


Are there any problems with heat disinfection with non-preserved saline? answer

I have always been told to advise patients not to shower with contact lenses in. So why is this allowed with silicone hydrogel lenses?

Secondly, can patients swim in these lenses? answer

60. Assuming the lens fits well is there any reason why I cannot fit a post LASIK patient with a continuous wear Silicone Hydrogel lens? answer
61. I have a 60 year old white female patient who was diagnosed with open angle glaucoma when she was 40. She currently uses Xalatan and Cosopt. I have prescribed Ciba Night and Day lenses. She is wearing them as a day wear lens.
Has there been any studies looking at the use of extended wear contact lenses with these and other anti-glaucoma medications? Would the medications be less effective if the patient used them when she was wearing her contact lenses?
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