With last month’s announcement of Texas ODs being able to independently manage glaucoma patients and Massachusetts’s law in January allowing topical glaucoma prescription authority, all 50 states now allow our profession to effectively manage this blinding condition. These legal rights mean we must become the primary providers and prescribers for glaucoma.
Optometry conducts 85% of all comprehensive eye exams in the US. You can expect that for every 100 exams you perform, about three should be glaucoma patients or suspects. Thus, you instantly have a glaucoma population to manage by simply seeing primary eye care patients, and these cases can add up. Below I’ll discuss the ways to properly and effectively test and manage glaucoma patients.
To effectively manage glaucoma, you’ll need the ability to examine the optic nerve and determine its size, estimate vertical vs. horizontal C/D ratio and recognize the presence of disc hemorrhages, pallor or notching. With time, you’ll pick up nerve fiber layer defects. This, combined with IOP, visual field testing and pachymetry, will get you started. Before long, however, an OCT device will be particularly warranted.
To advance further, especially in diagnosis of borderline cases, newer technologies to consider include hysteresis, ganglion cell complex assessment on OCT, faster perimetry for patients who are reliable visual field test takers, progression analysis software and advanced pupil testing.
Two that have helped me greatly are hysteresis with the Ocular Response Analyzer (Reichert) and advanced pupil testing with EyeKinetix (Konan). Average hysteresis is around 10.3mm Hg. A glaucoma patient with low values is more likely to show visual field progression; if they are a glaucoma suspect, they’re more likely to develop glaucoma.1,2
Pupil testing is also quite beneficial because the vast majority of glaucoma patients have asymmetric ganglion cell loss, resulting in a positive relative afferent pupillary defect (RAPD).3 EyeKinetix easily reveals a clinically significant RAPD. Even when C/Ds, OCT or pachymetry were borderline in many of my glaucoma suspects, those with no RAPD and hysteresis above 10.5 haven’t progressed to glaucoma. It allows me peace of mind to know when to start treatment and also to identify who is likely to be a fast progressor (e.g., hysteresis < 8mm Hg).
We’re entering an era where focusing on the ocular surface is critical to maintaining drop adherence. We need to move beyond medical management in patients experiencing ocular surface disease. Optometrists can provide selective laser trabeculoplasty (SLT) in six states. Whether you practice in a state where you can perform the procedure or if you comanage, SLT is a great alternative to beginning a second medication. In patients with ocular surface disease, dexterity challenges or adherence issues, it may even be a better initial choice.
Minimally invasive glaucoma surgery is a low-risk option for cataract patients. This is a great opportunity for those with glaucoma, but after cataract surgery it’s no longer an option. New modalities like bimatoprost SR (Durysta, Allergan) show lasting effects for more than 18 months after a single time-released implant is inserted in the anterior chamber.4
Glaucoma management is squarely in optometry’s domain. It’s most often a slowly progressive disease that gives us ample time to contemplate our next move. Patients need years of ongoing care and, with that, a lasting bond with a trusted, long-time care provider. In short we have the patients, and the patience, for it.
There is a safety net—specialists that handle advanced forms like pigmentary glaucoma and cases that progress while on treatment—but it’s imperative you make glaucoma a part of your everyday practice.
Dr. Karpecki is medical director for Keplr Vision and the Dry Eye Institutes of Kentucky and Indiana. He is the Chief Clinical Editor for Review of Optometry and chair of the New Technologies & Treatments conferences. A fixture in optometric clinical education, he consults for a wide array of ophthalmic clients, including ones discussed in this article. Dr. Karpecki's full list of disclosures can be found here.
1. Gustavo De Moraes CV, Hill V, Tello C, et al. Lower corneal hysteresis is associated with more rapid glaucomatous visual field progression. J Glaucoma. Apr-May 2012; 21(4):209-13.
2. Potop V, Corbu C, Coviltir V, et al. The importance of corneal assessment in a glaucoma sus-pect — a review. Rom J Ophthalmol. Oct-Dec 2019; 63(4):321-26.
3. Besada E, Frauens BJ, Makhlouf R, et al. More sensitive correlation of afferent pupillary defect with ganglion cell complex. J Optom. Apr-Jun 2018; 11(2):75-85.
4. Craven ER, Walters T, Christie WC, et al. 24-Month phase I/II clinical trial of bimatoprost sus-tained-release implant (Bimatoprost SR) in glaucoma patients. Drugs. 2020 Feb; 80(2):167-79.