GP insights

A GP Lens Settles a Diagnosis; and a Bet

BY BRAD GIEDD, OD, MS, FAAO

When is a GP lens more than just a contact lens? When you're trying to settle a bet, of course. An argument I was having with my partner recently inspired me to use our little debate as the subject for this column.

We were involved in a back-and-forth about a patient's cornea — a patient with a long history of successful soft toric contact lens wear and no real complaints. The patient was new to our practice and had come in for a comprehensive examination.

The Initial Exam

Our contact lens service includes baseline topography on every new contact lens patient and every contact lens wearer who is new to our practice. The patient's topography revealed a slight irregularity to the toric corneas, one eye more apparent than the other. The patient's refraction, however, was straightforward with relatively normal retinoscopy reflexes. The only evidence of any type of issue was a minimally reduced, best-corrected visual acuity of 20/20-2 in the eye in question.

Figure 1. Image showing the typical, inferonasal apical touch that is often unavoidable in spherical GP keratoconus fitting.

Slit lamp evaluation of the cornea revealed a normal appearance with no observable irregularity or other anomaly.

I suggested the potential for keratoconus; my partner quickly scoffed and suggested I was too quick to diagnose disease.

Nothing measured to this point was conclusive, however. So how would we settle this argument? With a GP contact lens, of course!

I anesthetized the patient and proceeded to place on his eye a GP trial lens with a base curve approximately 0.50D flatter than the measured steep meridian and voila: the fluorescein pattern revealed a small, inferonasal area of mild touch that we've all come to know is indicative of keratoconus. Figure 1 shows a similar case.

The bet was settled, my partner conceded and I will soon enjoy a steak dinner at his expense.

A New Understanding

While this particular diagnosis did not serve as any earth-shattering revelation to the patient — who continues to wear soft toric contact lenses — it did at the very least prepare him for what may very well be a part of his future should his keratoconus progress.

The patient now understands much more about his eyes, his condition and how we might manage it should it progress. The case also highlights an often overlooked use of GPs. GPs aren't only valuable for treatment, they're also valuable diagnostic tools to help explain perplexing patient presentations. CLS

Dr. Giedd entered private practice with the Eye Associates of Winter Park in 2000, where he specializes in tting specialty contact lenses and also performs clinical research for Vistakon.