Advancing therapies help treat wide variety of ocular surface disease patients

Issue: November 10, 2009

ByRichard L. Lindstrom, MD

Richard L. Lindstrom

Ocular surface disease includes the triad of dry eye disease, blepharitis and ocular allergy. These three conditions, according to some studies, affect at one time or another nearly half of the U.S. population and generate as many as one-third of the office visits seen in a typical comprehensive ophthalmology practice. They may present alone or in combination.

For example, in the elderly patient, dry eye is almost always associated with blepharitis, and blepharitis is almost always associated with dry eye. Of interest, some studies suggest that as many as 50% of patients with ocular surface disease are misdiagnosed — for example, treating for dry eye when the primary issue is blepharitis, or for allergy when the primary diagnosis is dry eye. This leads in many cases to ineffective and inappropriate therapy, frustrating for both the ophthalmologist and the patient.

After 35 years of practicing as a consultative cornea consultant and also suffering from mild dry eye, associated posterior blepharitis and seasonal allergic conjunctivitis, I have a few thoughts to share.

Symptoms and signs

Symptoms are often present without signs. And signs can be present without symptoms, likely caused by a secondary reduction in corneal sensitivity. The symptoms that are most helpful to me for dry eye are a gritty/foreign body sensation worse later in the day or when exposed to desiccating environments, such as a car defroster, or long-term computer usage when blink rates are reduced. Blepharitis burns, and the burning is worse in the morning and often associated with mattering. Allergy itches, especially right over the caruncle, and most patients with significant allergy are driven to eye rubbing until treated, exacerbating the symptoms by releasing mediators such as histamine from the mast cells.

Elucidating the difference between gritty/foreign body sensation worse late in the day vs. burning and mattering worse upon wakening vs. itching over the caruncle that prompts eye rubbing often helps establish the correct diagnosis. Of course, blepharitis almost always leads to an unstable tear film and evaporative dry eye, so whenever one is present, the other should be looked for carefully.

In regards to signs, I have been disappointed by Schirmer’s testing except when near zero in a patient with Sjögren’s syndrome. I find external and slit lamp findings much more useful, especially in conjunction with fluorescein and lissamine green staining, which replaced rose bengal for me a decade ago. I have learned to look at the faces of my patients for any evidence of rosacea, which is widely present in at least a mild form. I look at the lid margins carefully for signs of anterior and posterior blepharitis; estimate the tear meniscus; look for conjunctivochalasis, conjunctival edema, superior limbic follicles or micro or giant papillary reaction (evert the upper lid when in doubt); evaluate tear breakup time; and stain with fluorescein and lissamine green, looking at the staining pattern.

A subtle finding of a compromised ocular surface is significant staining in the zone on the cornea where the applanation tonometer was applied. Soon, a simple office-based test for tear film osmolarity will be available, and I expect this to be quite useful in both diagnosis and monitoring the impact of therapy.

Treatment

Finally, a few thoughts about therapy. I was trained 35 years ago to use an incremental approach, starting with simple therapies such as heat, lid hygiene and artificial tears. Patients were then brought back 2 to 4 weeks later and evaluated for therapeutic response, and additional therapy was added until the disease process was stabilized. I have since learned as a clinician and from personal experience that significant inflammation is associated with the pathogenesis of all ocular surface disease.

The clinician’s first job is to manage the inflammation. When confronted with a patient with acute iritis, no clinician would start with hot packs and artificial tears or try a mild topical steroid once a day for 2 weeks and then increase incrementally until a response is achieved. This frequently used incremental approach often results in a disappointed patient and a loss of confidence in the physician. When we see iritis, we treat aggressively with anti-inflammatory therapy, including topical steroids, until the disease is controlled and then taper. If the disease flares, we treat aggressively again. Chronic inflammation is bad for the inside of the eye, and it is bad for the ocular surface. I therefore now almost routinely treat initially with steroids in my ocular surface disease patients and then taper to maintenance therapy once the disease process is controlled and the patient is comfortable. This is, to me, logical, and fortunately it works well in all forms of ocular surface disease.

Of course, pressures must be monitored and herpes simplex avoided, but a short course of topical steroids four times a day (or even every 1 hour in acute allergy) for 2 weeks and twice daily for 2 weeks works wonders for dry eye, blepharitis and ocular allergy.

A few other thoughts on therapy include my clinical impression that doxycycline in a dose of 20 mg to 40 mg is equally effective to the higher doses we often prescribe; that omega-3s help blepharitis and dry eye; that good lid hygiene requires significant heat; that newer antibiotics such as azithromycin in a drop and a massage regimen at night represent an advance over the classical use of erythromycin ointment; that different patients prefer one artificial tear over another; and that once a patient learns their triggers, treatment before exposure to an allergen with a combination antihistamine/mast cell stabilizer is much more effective than treatment after.

Of course, cyclosporine drops, punctal plugs/occlusion, glasses, evaporation shields, serum tears and a long list of other agents add to our treatment capabilities when needed, and there are many agents in clinical trial that promise to help.

We are fortunate that newer diagnostics and therapeutic agents are advancing the art and science in this once frustrating class of ocular surface diseases. For sure, it is much more rewarding to treat these patients today than a decade ago, and every year our treatment options advance.