ERG Provides Confidence to Monitor or Treat

Patient History

A 32-year-old female was referred to our clinic for additional testing. She was diagnosed with glaucoma five years prior, at a very young age, and had been using a prostaglandin analog for most of that time. At the visit, she disclosed that she is a realtor and was tired of her clients commenting on her red eyes. As a result, she had stopped taking her medication 5 months prior. Her records revealed that there was no increase in her IOP since stopping the medication. At the current visit IOP was 13 mm Hg OD and 13 mm Hg OS. Central corneal thickness was slightly thinner than normal at 535 OD and 530 OS.

The fundus exam showed a .75 cup to disc ratio in the right eye and an .85 to .9 cup to disc ratio in the left eye (Figure 1). The discs also appeared slightly larger than normal, which raised my concern. I wanted to learn whether this patient truly has glaucoma or if she has physiologic cupping.

When we performed an OCT (Figure 2), the ganglion cell structure and retinal nerve fiber layer (RNFL) in the right and left eye were both flagged. The average RNFL thickness was 64 OD and 61 OS, which is very concerning and not what we would expect to see in a patient this age. However, the visual field looked pretty good (Figure 3).

           Figure 1: Fundus Photos                                                            Figure 2: OCT                                                             Figure 3: Visual Field