contact lens case reports
Guilty Until Proven Innocent
BY PATRICK J. CAROLINE, FAAO
In the process of any differential diagnosis, it�s always best to place the most probable causes of the problem at the top of your list. Solution sensitivity or incompatibility is such a common clinical finding today that I teach my students the following creed: When a patient presents with a soft lens complication, such as dryness or redness, the lens care products are guilty until proven innocent.
In the past, lens care formulations often were so toxic that they produced pathology that was easily diagnosed by observing the patient as he sat in the waiting room (Figure 1). Today, with the dramatic advances in solution formulation, diagnosis isn�t so obvious. As lens care products have evolved, so have the symptoms and signs of solution complications. It�s imperative that we rule out all lens care products, as well as topical medications and tear supplements, as the cause of the problem.
Youthful Case of KCS?
A case in point is patient DB, a healthy 22-year-old female college student with a 4-year history of wearing 2-week planned replacement lenses, with nightly disinfection in a brand name, multipurpose disinfection solution. The patient presented with a 6-month history of dryness and decreasing lens tolerance that her local eyecare provider diagnosed as keratoconjunctivitis sicca. She was prescribed appropriate tear supplements as a treatment.
Keratoconjunctivitis sicca or dry eye is a relatively rare event in a young, healthy, noncontact lens wearing individual, who is free of any systemic disease and systemic medications. In this case, we simply asked: �Are your dry eye symptoms less (or eliminated) when you discontinue your contact lenses and wear eyeglasses?� The patient reported that her dry eye symptoms were significantly improved when wearing her eyeglasses. It�s clear that patient DB is one of the millions of patients worldwide who is experiencing contact lens-induced dry eye.
Elusive Objective Findings
Our patient presented with no abnormal corneal, conjunctival or tear film findings. Today, this is a common clinical finding in a patient suspected of having a solution sensitivity. Often, in my experience, the only slit lamp finding of a possible solution complication, surprisingly, is increased inflammation of the upper tarsal plates (Figure 2). Why the tarsal conjunctiva is more sensitive to chemical exposure than the bulbar conjunctiva is a topic worthy of debate and eventual clarity.
In any event, I continue to teach the creed that for many contact lens complications, the solution is guilty until proven innocent.
Patrick Caroline is an associate professor of optometry at Pacific University. He is also a consultant to Paragon Vision Sciences and SynergEyes Inc.