Dry Eye Dx and Tx
Inspiration for Eyecare Diligence from an Unlikely Source
By Katherine M. Mastrota, MS, OD, FAAO
Those of you who know me know that I was born and raised in New York City and now live in Brooklyn, which is, according to GQ magazine, “The Coolest City on the Planet.” I do, however, own a small, Cape Cod-styled home on Kent Island, Md. Kent Island was the first permanent English settlement in North America, and the area of my home remains almost as rural as when the first settlers tilled the soil, fished the Chesapeake Bay, and culled for oysters.
Signs of Infestation
Why do I tell you this? Well, each July we spend a week or so in our house. During our stay we plan visits from the arbor specialist, John, to cut back and feed the 100-year-old mulberry tree in our yard; the John Deere specialist, Dave, to overhaul and repair the tractor; the well man, Charles, to check the water pump; Chuck, the sewage man, to monitor the drain field; and Ed Henehan, the exterminator, to inspect the house for obvious reasons.
This year it took all of 20 seconds for Ed to announce that we had an infestation of carpenter bees—20 seconds. He simply walked around the pool house, pointed his finger and said, “There.” Shocked, we realized that every day we walked by the telltale signs of infestation, oblivious to the damage that was being caused by the bees drilling into the support beams of the pool house. Ed's experienced, professional, and trained eye made a diagnosis that was so obvious, it embarrassed me.
It struck me like a two-by-four that we as eye physicians are in some ways like Ed, looking for signs of infestation—not of carpenter bees, but of other critters that have made haven in ocular structures, namely Demodex.
The association between Demodex infestation and blepharitis was found to be statistically significant by meta-analysis (Zhao et al, 2012). Demodex also has been associated with trichiasis (Gao et al, 2007), meibomian gland dysfunction (Gutgesell et al, 1982), conjunctival inflammation (Liu et al, 2010), and corneal pathology (Kheirkhah et al, 2007). Furthermore, infestation of Demodex mites induces a change of tear cytokine levels, IL-17 especially, which causes inflammation of the lid margin and ocular surface (Kim et al, 2011).
Just as tiny, cylindrical bored holes in the pool house lumber and a spray of carpenter bee debris on my pool screen were signs of bees working away on the premises, eye lashes with cylindrical dandruff are pathognomonic for ocular Demodex infestation (American Journal of Ophthalmology, 1982; Gao et al, Sept. 2005).
Treating the Problem
A number of methods have been described for the treatment of Demodex blepharitis. Treatment with tea tree oil has been proven effective and has become popular (Gao et al, Nov. 2005). Methods exist for concocting a diluted preparation of tea tree oil to apply to the lash margin, or there are readily available tea tree oil-containing shampoos and soaps.
There also are commercially available products developed specifically to treat ocular Demodicosis. These include Cliradex (available directly from the Ocular Surface Research and Education Foundation), OcuSoft Lid Scrub Plus, and now the Demodex Convenience Kit (OcuSoft), which contains a specially designed brush (BlephBrush) to apply the tree oil solution and help remove lid debris.
My point of the column is this: be like Ed. Recognize Demodex. Eradicate it. CLS
For references, please visit www.clspectrum.com/references.asp and click on document #202.
|Dr. Mastrota is secretary of the Ocular Surface Society of Optometry. She is center director at the New York office of Omni Eye Services. Contact her at firstname.lastname@example.org.|