History, clinical exam retain primary role in dry eye

By Cheryl Guttman Krader

Las Vegas-Pre-existing dry eye can affect the outcomes of excimer laser refractive and cause significant postoperative morbidity as well as patient dissatisfaction. Therefore, preoperative screening for dry eye is critical, said Michael B. Raizman, MD.

Although there are many new modalities for assessing the tear film and diagnosing dry eye, patient symptoms and findings at the slit lamp are still the key for clinical decision-making, said Dr. Raizman here at Refractive Surgery 2015 during the American Academy of Ophthalmology annual meeting.

“The new diagnostic tests play a corroborative role, but none is ready to guide us as a standalone indicator of patient candidacy for refractive surgery,” said Dr. Raizman, associate professor of ophthalmology, Tufts University School of Medicine, Boston.

“I would love for these new tests to be better able to quantify what I am not doing clinically through my slit-lamp examination,” he said. “However, we still need clinical studies to look at how they will help us and to determine which of these tests will be helpful.”

Dr. Raizman said that even in this day of technology, history is key to identifying patients at risk for a suboptimal outcome because of dry eye.

Talk to patients and ask them a few questions, he suggested.

“I ask about the frequency of artificial tear use and if the eyes are dry when a patient is not wearing contact lenses,” Dr. Raizman said. “The answers to these questions can be key indicators of how well they will do after refractive surgery.”

Questionnaires, such as the Ocular Surface Disease Index, can also be helpful. In addition, Dr. Raizman places a lot of emphasis on findings at the slit lamp, looking at the tear break-up time, tear meniscus, and corneal and conjunctival staining.

He supplements those traditional evaluations with tear osmolarity measurement, assay of matrix metalloproteinase-9 in tears, aberrometry, and corneal topography. Then he interprets the findings of these diagnostic tests in the context of patient symptoms and the slit lamp examination.

A diagnosis of dry eye disease does not necessarily exclude a patient from refractive surgery.

“Many of these individuals can be good candidates for surgery after appropriate therapy,” Dr. Raizman said.

Specific findings that represent absolute contraindications for keratorefractive surgery include a Schirmer test of 0, a miniscule tear meniscus, and filamentary keratitis.

Dr. Raizman said that he would not necessarily exclude patients with autoimmune disease (e.g., rheumatoid arthritis, lupus) if they appear to have a healthy ocular surface.

However, a diagnosis of a neurological disease or use of antidepressant medications raises a red flag.

“Borderline” patients whose ocular surface can be rehabilitated with treatment and by addressing potentially reversible risk factors are reassessed for improvement prior to proceeding with surgery.

Dr. Raizman said his criteria for determining whether it is appropriate to perform a keratorefractive procedure include resolution of symptoms and ocular surface staining, no to minimal use of artificial tears, and a good quality tear film on the slit-lamp exam.

“The bottom line is that whenever in doubt about whether a patient is an appropriate candidate for excimer laser refractive surgery because of the condition of the ocular surface, don’t treat and consider a non-ablative refractive procedure instead,” he said.