Gauging Glaucoma Suspects
Gauging Glaucoma Suspects
Nerve damage from glaucoma progresses very slowly, so be sure your diagnosis is right before you initiate treatment.
By Dan Beck, OD, Leland, N.C.
IT NEVER CEASES TO amaze me how decisions and conclusions pertaining to patients' eye health are made. While each doctor puts his own spin on patient care, critical pieces of the diagnostic puzzle are often overlooked or ignored completely. No single disease demonstrates this better than primary open angle glaucoma (POAG).
In my opinion, most people are diagnosed and placed on topical glaucoma medication long before medication is necessary. An intraocular pressure over 25 sends many ODs into panic mode. The mentality of "Get that pressure down now" takes over, and trials, both monocular and binocular, are initiated. Once a patient has been placed on drops, they're often stuck in a lifelong eye drop abyss, with little chance of getting out. So next time you're thinking POAG, remember these case studies and consider the lessons inherent in them.
Glaucoma or Thick Corneas?
Patient #1 is a 55-year-old white man who was diagnosed with open angle glaucoma 13 years ago by an optometrist in another state. The patient told me his initial pressures were found to be 25 in both eyes. He'd been taking Timoptic XE for that entire time period. This may seem like a simple case, but without access to his previous medical records, there was one thing I wanted to know: his central corneal thickness results.
We performed pachymetry and found readings of 625 OD and 628 OS. His IOPs were 17 and 18, but taking the corneal thickness into account, his pressures were actually around 12. Even if the Timoptic provided a 30% drop in his IOP, which is rare, his true pressures would be around 17. His optic nerve cupping was graded at .35 OU. OCT testing was found to be normal OU.
Bottom line: this patient never had glaucoma. He just had very thick corneas. Think how much money was wasted on unnecessary medication for all those years. Consider the potential for side effects, especially with prolonged usage.
Combination or Monotherapy?
Patient #2 is a 68-year-old black woman who came to our office with all of her glaucoma medications in hand. She was taking timolol, Alphagan and Travatan. She said her previous doctor added the Travatan about a year ago when her pressures began "creeping up." She'd been taking timolol and Alphagan for several years.
We measured her pressure at 14 OU. I asked if her doctor had tried replacing the timolol and Alphagan with the Travatan instead of just adding it. She said no. Prostaglandins almost always lower IOPs better than other drugs. So, we had her discontinue the timolol and Alphagan, and instead, use only Travatan. On subsequent visits, her pressures never rose above 15. Again, a substantial amount of money was wasted on medications that had become obsolete for this patient.
Think Before You Treat
The one good thing about primary open angle glaucoma � if there is a good aspect � is that, in almost all cases, it progresses very slowly. Nerve damage takes years to occur, not weeks or months. It�s easy to forget that when the patient in your chair has IOPs above 25. But remember to make time for thorough testing and careful diagnosis, so you can make an educated decision before initiating treatment. The time spent up front will prevent misdiagnoses and unnecessary medications, and may save your patients a lot of money. nOD
Taking his good ole time, Dr. Beck is a 1993 graduate of the Pennsylvania College of Optometry. You can reach him at email@example.com.
Optometric Management, Issue: November 2009