Ophthalmology & Optometry/Contact lens - length of use


Hi, I've been wearing contacts happily for 30 years. I had been wearing Acuvue Bifocals for a long time, only recently switching to Acuvue Oasys. I take them out every night. No problems. Most manufacturers and optometrists say the lenses should be worn for two weeks then discarded. I routinely wear them 6 - 8 weeks without apparent problems; no clouding, irritation, nothing. My vision prescription has been stable for a long time. My question: Why the two-week recommendation? I can understand why manufacturers want me to discard them frequently, and perhaps optometrists don't want to buck that for liability reasons. Can you weigh in on the question of this two-week recommendation? Thanks.

Great question, Ken, and one we field very often.  
You will get slightly varying reasons from your eye care provider about this, but I think the simplest way to explain it is like this:
The reason the lens is safe for the ocular surface is because what the material is, and it's properties.  Change the material, change how it works on your eyes, right?  So imagine a rubber band sitting on your car dashboard for a month.  At a glance it looks the same, more or less feels the same, but the dynamics are totally different - it's more brittle, it doesn't stretch or rebound the same, etc.
Contact lenses are a bit similar.  Once exposed to the proteins in your tears, the UV from the sun, the chemicals in the solutions, etc, the material just doesn't hold up well.  So it may have roughly the same shape/properties, so it will still "work" as far as give you good vision, but it may not be healthy for the eye.
Another thing to remember is that just because the eye 'feels' good, doesn't mean that it is healthy.  As lenses age, and the cornea gets hypoxic (not enough oxygen because the lens isn't as breathable/etc), corneal sensation goes down - you physically will not 'feel' as much.  By the time your eye actually "feels" bad from an old contact lens, that means there is likely already damage done.  Metabolism has changed, hypoxia set in, inflammatory proteins released, and tissue remodeling is likely already occurring (blood vessels changing structure/shape).  Doing this for a month or so isn't a huge deal, and is reversible.  The problem is over time, a year or two, of this on and off health.  This can and will lead to permanent damage to the cornea, having long lasting effects on vision and eye health.  Irregular astigmatism you can't correct, corneal opacification and scarring, and new/abnormal blood vessel growth are the most common.
There are MANY other things we could get into about why to follow the recommendations, similar to there are 100 reasons on why to take your blood pressure medications (if you need it).  At the end of the day, they're regulated by the FDA for a reason - because they can cause harm if misused.  Please listen to your doctor's advice, I promise it's not because he wants you to spend and extra $50 on contacts - it's because he wants your eyes to stay healthy!
Good luck and throw those lenses out! :)

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John M. Dovie, OD, FAAO


As a residency-trained Fellow of the American Academy of Optometry I am able to answer most questions regarding eye and vision health. Anything is welcome, ranging from dry or allergy eyes, bifocal contact lenses, or thoughts on LASIK surgery. As I am not a surgeon, detail-oriented surgical-related questions may be better answered by an ophthalmologist.


Selected to participate in the PCO residency program in Philadelphia at The Eye Institute, where I worked OD and MD specialists gaining invaluable experience in various clinics including glaucoma, cornea and cataract, oculo-plastics, retinal disease, neuro-ophthalmic disease, primary care, emergency medicine, and special populations. Have practiced and trained in numerous settings including hospital, academic, retail and private practice. I earned my Fellowship in the American Academy of Optometry (FAAO). There are currently only about 3000 active fellows worldwide, and there are only about 70 Fellows in the state of Virginia. I currently own and operate my own optometric practice/clinic.

American Academy of Optometry, American Optometric Association (Contact Lens/Cornea Section member since 2001), Southwest Virginia Optometric Association, Virginia Tech Alumni Association

“Nyctalopia as the Presenting Sign of Vitamin A Deficiency: A Late Complication of Gastric Bypass Surgery.” Clinical Case Study Poster presented at The American Academy of Optometry Denver, Colorado, December 2006, co-authored with Bradley Lane, OD.
“The Importance of Considering Paranasal Sinus Mucocele as a Differential Diagnosis in Diplopia.” Clinical Case Study Poster presented at The American Academy of Optometry San Diego, California, December 2005, co-authored with Kelly Malloy, OD, FAAO and Cherie Farkash, OD.
“Acute Onset of Halos and Glare: Bilateral Keratitis—An Atypical Presentation of Amiodarone Keratopathy.” Clinical Case Study Poster presented at The American Academy of Optometry Tampa, Florida December 2004. Also Presented to New Jersey Academy of Optometry, Neptune, New Jersey March 2005.
“The Opportunity for an Optometrist to Save a Life.” Clinical Case Study and Grand Rounds Presentation presented at The Pennsylvania College of Optometry, Philadelphia, Pennsylvania, September 2004.
“Corneal whorls cause wonder.” Clinical Challenges Quiz, co-authored with Andrew Gurwood, OD, FAAO, Review of Optometry. Published 10/15/2006.
“Acute onset of halos and glare: bilateral corneal epithelial edema with cystic eruptions--atypical presentation of amiodarone keratopathy.” Co-authored with Andrew Gurwood, OD, FAAO. Published February, 2006, Optometry.
“Pondering the posterior polka-dots.” Clinical Challenges Quiz, co-authored with Andrew Gurwood, OD, FAAO, Review of Optometry. Published 5/15/2005.
Professional Involvement:
“AION: Amiodarone-Induced or Anterior Ischemic Optic Neuropathy?” Participated as a peer-review referee for Expert Review of Ophthalmology (London, UK); refereed 10/2006.

Bachelor of Science, Cum Laude, Virginia Tech. Bachelor of Science, Pennsylvania College of Optometry. Doctorate (OD), Pennsylvania College of Optometry Residency, Pennsylvania College of Optometry Fellow of the American Academy of Optometry

Awards and Honors
Winner, First Place, "Best Beside Manner" by Our Health Magazine: 2012, 2013, 2014 Winner, First Place, "Best Eye Doctor" by The Roanoke Times: 2013, 2014 Recognized as a Fellow of the American Academy of Optometry, December, 2006 Recipient of the Onofrey G. Rybachok Memorial Scholarship, 2000-2001 Member: The Golden Key International Honor Society Member: The National Biological Honor Society Member: The National Honor Society Eagle Scout awarded 1994

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