Visual and refractive outcomes hinge on health of ocular surface

Meticulous preoperative assessment of ocular surface disease is critical to clinical, refractive and visual outcomes after cataract and refractive surgery, a speaker said at OSN New York 2009.

"Lid margin disease and dry eye can be associated with significant patient discomfort as well as clinical signs," Helen K. Wu, MD, said. "It's imperative that the cornea be as normal as possible prior to cataract or corneal surgery to get the most accurate preoperative measurements."

Ocular surface conditions that can affect refractive surgery outcomes include blepharitis, dry eye, anterior basement membrane dystrophy, ocular allergy, inflammatory disorders and irregular astigmatism due to warpage, Dr. Wu said.

"We know that the quality of the ocular surface determines the quality of the image which is transmitted through the eye to the retina," she said. "We know that any diminution of this image will adversely affect contrast sensitivity and quality of vision."

Optimal treatments for blepharitis and keratoconjunctivitis include warm compresses, lid scrubs, topical antibiotics such as erythromycin and azithromycin, and oral antibiotics such as tetracycline. Dr. Wu said omega-3 supplements are used in her practice to help minimize the gastrointestinal side effects of oral antibiotics.

"It's important to treat blepharitis because it's often the source of an organism that can cause an infection after surgery," Dr. Wu said. "So we treat the pre-existing blepharitis as well as use antimicrobial prophylaxis immediately preoperatively. We know that blepharitis and dry eye can cause decreased tear breakup time, and that significantly degrades the quality of the retinal image. Dry eye is also associated with decreased visual function in activities of daily living."

Femtosecond LASIK flaps have been shown to cause minimal postoperative dry eye symptoms, Dr. Wu said.

"It seems that with femtosecond flaps, it isn't so important where you put the hinge," she said. "It appears that these thinner flaps have less denervation, so the symptoms are less severe and they resolve sooner."

OSN New York 2010 will be held November 19-21, 2010 at the Sheraton New York Hotel & Towers in New York City. Learn more at OSNNY.com.