Ocular surface disease
Looking beyond the obvious in dry eye cases
by Maxine Lipner EyeWorld Senior Contributing Writer
Dr. Dhaliwal watches patients closely at the slit lamp before using a fluorescein strip to stain the eye.
Source: Getty Images
Structural disorders contribute to dry eye symptoms
The first thing many practitioners think of when a patient complains of dry eye is that it is emanating from an imbalance in the tear system. However, this is not necessarily the case. Often a structural disorder is at the root, said Deepinder K. Dhaliwal, MD, professor of ophthalmology, University of Pittsburgh School of Medicine. The lid functional unit contributes to dry eye and to ocular surface problems more than 50% of the time, Dr. Dhaliwal said.
In the blink of an eye
Determining if a structural problem may be the issue begins when the patient first enters the exam room. Dr. Dhaliwal said its important not to overlook the external exam. From the minute patients walk into the room, she makes a point of watching them blink. Im checking if they have a decreased blink rate, as that greatly affects the ocular surface. In addition, a lot of people have incomplete lid closure, which leads to exposure keratopathy.
Dr. Dhaliwal watches patients closely at the slit lamp before using a fluorescein strip to stain the eye. I dont even tell them Im watching them blink, she said. I say, Just be normal. You can blink whenever you need to, because if you ask patients to blink, they will blink fully, Dr. Dhaliwal explained. She also tries to move the slit lamp around so theyre not focused on any one thing. Bennie H. Jeng, MD, professor and chair, Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, concurs. He stressed the importance of just watching the patient. Dr. Jeng finds that incomplete blinking goes along with a nocturnal lagophthalmos where patients may sleep with their eyes partially open. I see that pretty frequently, and thats something I check for in every new patient who comes in, Dr. Jeng said. Even if the issue is confined to incomplete blinks, its still going to affect the area that the eyelid does not reach. I tell people its like the part of the windshield that never gets the wiper, he said. Thats what the open area looks like on staining when they dont blink all the way down or they have lagophthalmos. To treat such patients, he begins by just asking them to remember to blink. This is not an option for nocturnal lagophthalmos, and different approaches are needed. You can offer them ointment at bedtime, he said, adding that many, however, will complain that if they get up to go to the bathroom at night, their vision is blurry. Another alternative is to tape the eyelid down. For this, Dr. Jeng recommends using Breathe Right snoring strips because they are super sticky on the ends. Patients can put one end on the upper lid and the other on the cheek, he explained. A third alternative is to sleep with tight-fitting swim goggles. What happens is it becomes a humid chamber, he said; however, this is not a favorite of patients. In some cases, surgical tightening may be the answer. Sometimes its the lower lid that is sagging a bit and needs to be lifted, he said. Other times, the eyelids can be closed a touch with a lateral tarsorrhaphy, but this is not a favorite of patients either, he finds, because it changes their appearance a bit. Youre pinching the eyelids closed a little bit from the side, he said. So youre making the eyes appear a little bit smaller. Dr. Dhaliwal finds that another underdiagnosed structural condition contributing to dry eye is floppy eyelid syndrome. We get patients who come in with super floppy eyelids and are getting eversion at night, Dr. Dhaliwal said, adding that they wake up with dry eye symptoms. She finds that this occurs more often in patients with keratoconus as well as those who have sleep apnea. Its important when you diagnose floppy eyelid syndrome to ask about sleep apnea, she said. Dr. Dhaliwal theorizes that the overlap between the 2 conditions is likely the result of lax collagen.
The treatment here is straightforward. You have to make sure patients stop rubbing their eyes, Dr. Dhaliwal said. These floppy eyelid syndrome patients are often chronic eye rubbers. This is something that links them to keratoconus patients, who also frequently rub their eyes. Dr. Dhaliwal can often tell the side that the patient sleeps on. This is usually the result of patients pushing on their lid skin while theyre sleeping, which causes it to evert. To treat such patients, Dr. Dhaliwal has them use nighttime lubrication such as ointment or gel. In some cases, we also have them use an eye shield when they sleep, she said; this keeps the lubrication on the eye and stops patients from rubbing their eye against the pillow while they sleep. Another condition that is often related is called mucus fishing syndrome. These people have floppy lids and chronic inflamed conjunctiva and mucus in their fornices, she said. To determine if they have the condition, Dr. Dhaliwal asks patients if they have a lot of mucus. If they say they do, she follows up by asking how they remove this. It is shocking to hear what they often say. She has had some patients who will take their finger and reach up into their upper fornix to get the mucus out, while others will use a rolled up Kleenex or handkerchief to do this. Its amazing how much trauma patients do to their ocular surface, she said. Treating this requires breaking the cycle of removing the mucus. I tell patients, Promise me you wont touch your eyes for 1 week. Theres a high likelihood that youre going to feel a lot better if you do that, she said.
Other ocular abnormalities
Dr. Jeng finds that conjunctivochalasis is another commonly overlooked condition related to structural dry eye. The common conjunctivochalasis that most people think about is where there is baggy conjunctival tissue, he said, adding the redundant tissue can cause friction, making the patients eye feel irritated. It causes a lot of tearing because the tissue can sag over the eyelid margin, Dr. Jeng said. Theres no place for the tears to collect, and the tears drip off onto the cheek. Sometimes, the sagging tissue actually blocks the lower punctum, also causing tearing. With all of this tearing, patients are sometimes misdiagnosed. Practitioners may erroneously think that patients are tearing because they are dry, but in reality its because they have an obstruction or an anatomical problem where the tears dont stay in the eye.
In addition, there is a type of conjunctivochalasis commonly referred to as superior limbic keratoconjunctivitis (SLK), Dr. Jeng said. This involves redundant tissue on the superior bulbar conjunctiva. Its a mechanical rubbing of the underside of the upper eyelid, and it is redundant tissue, so theres friction, Dr. Jeng said, adding that this causes inflammation on both the bulbar and the tarsal conjunctiva, the latter of which takes on a velvety appearance. Many times, before getting the right diagnosis, these patients have been treated for dry eye by as many as 5 different practitioners. They have been given all sorts of artificial tears, but lubricants arent going to work, Dr. Jeng said. To treat this, he finds that conjunctival excision to remove the redundant tissue, which is sagging and loose, is the definitive answer. Dr. Dhaliwal said that in addition to looking for bulbar conjunctival staining for SLK under the lid, some patients may have an exposed concretion. In these cases, biological material gets encased in a cyst, and if this ruptures the material becomes exposed and irritates the eye. You flip their lid, you see an exposed concretion, you pop it out with a little forceps, and they think you walk on water because you just cured them, she said. In identifying this, Dr. Dhaliwal stressed the need to use fluorescein strips moistened with balanced salt solution rather than a drop of stain, which puts more vehicle in the eye and can mask some cases. Another irritating condition to watch for is giant fornix syndrome. This relatively rare condition typically occurs in older patients who have deep superior conjunctival fornices. Organisms like bacteria are harbored up in that area and form a biofilm, and its very difficult to eradicate this infection, Dr. Dhaliwal said. You have to break through the biofilm and oftentimes have to use a combination steroid antibiotic drop. For some patients, Dr. Dhaliwal uses a betadine rinse or the anti-inflammatory antiseptic agent Avenova (NovaBay Pharmaceuticals, Emeryville, Calif.), which has activity against biofilm.
Dr. Jeng said that to tackle these structural cases, when patients come in complaining of dry eye, its important to think beyond the obvious. I always tell residents that just because patients say they have dry eyes doesnt mean they actually do, Dr. Jeng said. Do a complete exam and always check and make sure that they close their eyes all the way and that they blink all the way down.
Editors note: Dr. Dhaliwal has financial interests with Abbott Medical Optics (Abbott Park, Ill.), Dompe (Milan, Italy) and NovaBay Pharmaceuticals. Dr. Jeng has no financial interests related to this article.