Help ! Can Contact Lenses Cause Me To Go Blind

THE BAD NEWS
The truth is YES, wearing contact lenses significantly increases the risk of serious eye infections, which can result in blindness. Microbial Keratitis ( Corneal Bacterial Infection) can result in visually insignificant scars through to complete corneal opacification and blindness. These risks are exponentially higher in people that sleep in their contacts, something termed Extended Wear. A decade ago we (the eyecare community) actively promoted continuous or extended wear, but as time has gone on the 6x increased risk of serious eye infection has swayed most responsible practitioners to discourage this type of contact lens use.

THE GOOD NEWS
Contact lenses are a great solution to many peoples visual needs. They are extremely safe to wear, when worn responsibly. So what should you do?
Never sleep in contacts
Never swim in contacts, especially not in a public pool, spa, creek or river
Don’t buy contacts online, what are you getting, Ive seen many horror stories
Go for daily contacts, not 2 weekly , not monthly, would you wear the same socks everyday, or would you put a clean sterile pair on
See your Optometrist regularly, at a minimum on a yearly basis
If your eyes get red, sore, produce mucous, or you feel glare sensitive, see your Optometrist as soon as you can

MICROBIAL KERATITIS
It is easy to be lax when your eyes get red and sore, but you should seek the examination of your eyes by an Optometrist. Most Optometrists now are able to differentiate between an allergic, viral or bacterial conjunctivitis or keratitis (more severe) and prescribe medication if required.
So what is bacterial keratitis

Bacterial keratitis is an ocular emergency that if not treated appropriately can have sight and eye threatening consequences. The type and frequency of the medication used as therapy is dependent on the severity of the ulcer. Due to the potentially severe complications, aggressive treatment with a fluoroquinolone hourly during waking hours with am initial loading dose every five minutes for thirty minutes is the minimum treatment required. Longer loading doses and more frequent dosing should be implemented when the ulcer is central or large. Additional antibiotic ointments such as tobramycin at night can also be used.

In Optometric practice microbial keratitis is an important consideration, particularly in regards to contact lens wearers. Bacteria is the most likely causative agent in ulcerative keratitis, accounting for as much as 80% of these presentations. The complications of this can be sight threatening especially when more virulent strains such as Pseudomonas are involved. The four main bacteria responsible for bacterial keratitis are Streptococcus, Pseudomonas, Enterobacteriaceae, and Staphylococcus
Bacterial keratitis is essentially the ulceration of the cornea due to bacteria that have entered through a compromised epithelial layer of the cornea. It can result in corneal scarring, irregular astigmatism and most severely, corneal perforation, which may then cause endophthalmitis.
Typically patients present with a painful, red, photophobic and mucousy eye. Examination shows an ulcerated area of epithelium with surrounding infiltrate, hyperemia, possibly lid swelling and anterior chamber reaction. In severe cases a hypopyon and posterior synechiae may occur. Up to 42% of patients with bacterial keratitis are contact lens wearers with the highest risk occurring amongst extended wearers. Contact lens wearers are also more likely to have more severe infection such as Pseudomonas (2). Other risk factors are other trauma (non-contact lens), immune-compromised individuals, dry eyes, lid conditions such as ectropian, other corneal disease and topical steroid use.
When examining patients with suspected bacterial keratitis, other conditions should be ruled out. These include other microbial keratitis (viral, fungal), marginal keratitis, ocular rosacea, scleritis, interstitial keratitis, neurotrophic keratopathy, and band keratopathy (1).
Prior to treating bacterial keratitis a scrape or culture should be taken to identify the pathogen responsible if required. This is more likely needed if the ulcer is large, central or when fungus or acanthamoeba are suspected. Backup culture sources such as contact lens cases and solutions should be kept. Treatment regime varies amongst practitioners with corneal eye specialists more likely to perform cultures than non-corneal eye specialists. Corneal specialists are also more likely to use fortified broad spectrum antibiotics as opposed to fluoroquinolones for severe infection than non-corneal eye specialists (3). As 60 - 80% of U.S. eye specialists state that fortified broad spectrum antibiotics are more effective than fourth generation fluoroquinolones, Optometrists must consider if these are required in severe cases.

Take Home Advice
Follow your Optometrists advice
Wash your Hands before touching your eyes or contacts
Opt for daily dispoable contacts
Never Swim or Sleep in contacts
If you experience red sore mucousy or glare sensitive eyes see your Optometrist ASAP
References
Murillo-Lopez F, Wilson J, Law S, Rapuano C, Brown L, Roy H. Bacterial Keratitis. 2014 August: Available at http://www.emedicine.medscape.com. Accessed October 24, 2015.
Stern G. Pseudomonas keratitis and contact lens wear: the lens/eye is at fault. Cornea. 1990; 9(1): 36-40.
Park J, Lee K, Zhou H, Rabin M, Jwo K, Burton W, Gritz D. Community practice patterns for bacterial ulcer evaluation and treatment. Eye Contact Lens. 2015 January; 41 (1):12-18. [Pubmed].
Hoddenbach J, Boekhoorn S, Wubbels R, Vreugdenhil W, Van Rooij J, Geerards A. Clinical presentation and morbidity of contact lens-associated microbial keratitis: a retrospective study. Graefes Arch Clin Exp Ophthalmol. 2014 February; 252(2): 299-306.
Rasoulinejad S, Sadeghi M, Montazeri M, Hedayati G, Akbarian N. Clinical Presentation and Microbial Analysis of Contact Lens Keratitis;an Epidermiologic Study. Emerg (Tehran). 2014 Fall; 2(4): 174-177.
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Khokhar S, Sindu N, Mirdha B. Comparison of topical 0.3% ofloxacin to fortified tobramycin-cefazolin in the therapy of bacterial keratitis. Infection. 2000 May-June; 28(3): 149-152.
LaBorwit S, Katz H, Hirschbein M, Oswald M, Snyder L, Scwartz K, Herling I. Topical 0.3% ciprofloxacin vs topical 0.3% ofloxacin in early treatment of Pseudomonas aeruginosa keratitis in a rabbit model. Annals of Ophthalmology. 2001 March; 33(1): 48-52.
Tuft S, Burton M. Microbial keratitis. The Royal College of Ophthalmologists – Focus. 2013 autumn: 5-6.
Gokhale N. Medical management approach to infectious keratitis. Indian J Ophthalmol. 2008 May- June; 56(3): 215-220.
AAO Cornea/External Disease PPP Panel, Hoskins Centre for Quality Eye Care. Bacterial Keratitis PPP- 2013. 2013 October. Available at http://www.aao.org. Accessed October 25, 2015.
Melki S, Safar A, Scharper P, Scharper M, Zeligs B, MacDowell A, Goldberg M, Lustbader J. Effect of topical povidone-iodine versus ofloxacin on experimental Staphylococcus keratitis. Graefes Arch Clin Exp Ophthalmol. 2000 May; 238(5): 459-462.
Michalova K, Moyes A, Cameron S, Juni B, Obritsch W, Dvorak J, Doughman D, Rhame F. Povidone-iodine (betadine) in the treatment of experimental Pseudomonas aeruginosa keratitis. Cornea. 1996 September; 15(5): 533-536.
Gregori N, Schiffman J, Miller D, Alfonso E. Clinical trial of povidone-iodine (Betadine) versus placebo in the pretreatment of corneal ulcers. Cornea. 2006 June; 25(5): 558-563.
Dart J -NHS. Royal College of Ophthalmologists Guidelines – Managing Microbial Keratitis. 2014. Available at http://www.moorfieldsresearch.org.uk. Accessed October 25, 2015.