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Therapeutic Topics An Update on Blepharitis TreatmentLeasing new technology offers several advantages over buying. Before you decide, though, read the lease agreement carefully.Ira J. Udell, MD,
Lauren Nally, BS, and Mark B. Abelson, MD , Understanding Blepharitis Many have tried to classify blepharitis. Researchers have categorized it into six groups.2 These classes include staphylococcal, pure seborrheic, seborrheic associated with a staphylococcal component, seborrheic with secondary meibomian seborrhea, seborrheic with secondary meibomiantitis and meibomian keratoconjunctivitis. In a clinical setting, however, patients don’t always fall into a category, but instead, into a continuum. Considering the lid anatomy may be more practical when classifying blepharitis. Anatomical classifications may be appropriate if they cause you to look more carefully at the lid margins. Depending on which part of the lid is affected, blepharitis is classified as anterior, posterior or angular. Anterior blepharitis is associated with staphylococcal infections and seborrheic dermatitis.  Posterior blepharitis is associated with meibomian gland
dysfunction, often co-existing with rosacea, and seborrheic dermatitis. Angular
blepharitis affects the medial or lateral canthal regions and is often
associated with Moraxella infections or atopy.3 When presenting
treatments, the clinician must consider that ocular conditions, such as dry
eye, rosacea, corneal changes and general seborrhea, can co-exist with
blepharitis. Inflammation of the eyelid margin, one of the classic signs of blepharitis. Clinical Signs and Symptoms Signs of blepharitis are burning, itching, debris or scales along the lash line, greasy coating of the lashes, hyperemia, pachyblephoron lid notching, missing or misdirected lashes and collarettes. The debris, scales and greasy coating are products of the keratinization and metabolic debris from the bacteria, but what of the collarettes? They don’t sit in cylinders on the base of the lash, but appear to extend over the lid margin. This translucent sheet of hyperkeritinization is often evident if you strip back the collaretes. Is this a failure to desiccate, or hyperkeritinization? At the slit lamp, a clinician will see missing/broken lashes. This suggests some folliculitis, which may be evident. Diffuse hyperemia may also be seen, resulting in pink-rimmed lid margins often occurring with rosacea. The atopic lid itches, and, especially when secondarily involved with staphylcoccals, ulcerative blepharitis can occur. Meibomian gland changes also may be seen. These glands develop an operculum, which completely blocks the opening, or scarring. Chronic inflammation may cause scarring of the meibomian glands, but what is the operculum’s etiology? We don’t yet understand how the meibomian glands secrete. Perhaps it’s due to the action of the Riolan’s muscle as we blink or some other unknown mechanism. Inspissation of the meibomian glands reduces the quantity of lipid secretion, accelerating tear break-up time. Blepharitis further affects the secretions, making them viscous and opaque. Keeping them clear and oily depends upon maintaining a delicate balance. Dry eye occurs alongside blepharitis when the meibomian gland secretions are disrupted and evaporation is enhanced, causing destabilization of the tear film.4 Further signs of blepharitis include inflammation and irregular lid margins. These disrupt the “wiper blade function” of the lid, leaving dry spots and causing incomplete blinks, which lead to inferior punctate keratitis.1 Failure to treat such cases properly risks the persistence of symptoms. The incidence of blepharitis increases with age, with the majority of those affected being over 50. This begs the question: Why does the gray line, that precise demarcation between squamous and mucous membrane, become violated with age? What is the significance of skin demarcation that becomes evident with chronic inflammation and with squamous metaplasia? Treatment Options Today, blepharitis remains a chronic condition with no cure. The goals of treatment are to control symptoms and prevent complications. Consider both the location and the co-existence of other ocular conditions. Various combinations of lid hygiene, topical antibiotics and systemic antibiotic therapy may help.
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