Dry Eye Dx and Tx
The Mastrota Rotation
BY KATHERINE M. MASTROTA, MS, OD, FAAO
The study of the tear film and ocular surface is peppered with the names of individuals who have strived to elucidate and characterize this complex system, which when dysfunctional is referred to as ocular surface disease.
Vogt has his palisades, Krause and Wolfring, accessory glands. There are Bitot’s spots and Meibomian glands. So, following their lead, I dare to proudly (and selfishly) introduce a diagnostic maneuver, the Mastrota Rotation, to detect Demodex organisms within the eyelash follicle.
Demodex Defined
Generally considered a harmless saprophyte of the skin, growing opinion suggests that Demodex can be pathogenic to some individuals. It is speculated that Demodex overpopulation (demodicidosis) is responsible for various skin diseases such as rosacea, perioral dermatitis, and blepharitis. In fact, the association between Demodex and blepharitis was validated by meta-analysis (Zhao et al, 2012).
Demodex has also been associated with trichiasis, meibomian gland dysfunction, conjunctival inflammation, and corneal pathology. Infestation of Demodex mites also induces change of tear cytokine levels, in particular IL-17, which causes inflammation of the lid margin and ocular surface (Kim et al, 2011).
Using the Mastrota Rotation
To date, the preferred method for identifying Demodex organisms within the eyelash follicle is by microscopic inspection for mites on an epilated eyelash. Personal clinical experience, however, has demonstrated that rotation of the eyelash within the lash follicle can, in effect, scrape out mites that reside within the lash follicle.
In this maneuver, the eyelash is rotated, as a spatula in a bowl, around the inner perimeter of the eyelash follicle. Demodex mites are essentially churned out of the follicle and emerge in toto on the lid margin. Mites can be visualized at most higher-power slit lamp magnifications. By this rotational maneuver, I have found that Demodex mites can be isolated in follicles whose lashes may not display the characteristic tubular base cuffing pathognomonic for ocular Demodex infestation (Mastrota, 2013). Eyelashes in compromised follicles, damaged by Demodex activity, may not tolerate this maneuver and be pulled from the follicle.
Treatment Options
A number of methods have been described for the treatment of Demodex blepharitis. Tea tree oil has been effective and popular (Gao et al, 2012). Methods exist for concocting a diluted preparation of tea tree oil to apply to the lash margin, but tea tree oil-containing shampoos and soaps are readily available.
Better yet, commercially available products developed specifically for the treatment of ocular demodicidosis include Cliradex (available directly from the Ocular Surface Research and Education Foundation [osref.org]), OcuSoft Lid Scrub Plus, and the Demodex Convenience Kit (Ocu Soft), which contains a specially designed brush (BlephBrush) to apply the proprietary tree oil solution and to help remove lid debris in the exam room.
How these products could work combined with a novel mechanical lid cleaning instrument—BlephEx (Rysurg)—is a question of interest. I am excited to pair these Demodex treatments and report my findings back to you. CLS
For references, please visit www.clspectrum.com/references.asp and click on document #214.
Dr. Mastrota is secretary of the Ocular Surface Society of Optometry and center director at the New York office of Omni Eye Services. She is a stock shareholder of TearLab Corporation and a consultant or advisor to OcuSoft, B+L, Allergan, Alcon, BioTissue, and Nicox. Contact her at katherinemastrota@msn.com.