Article

A.C.T. on Glaucoma

Play a significant role in staving off disease-induced blindness

Pablo Picasso once said, “Our goals can only be reached through a vehicle of plan, in which we must fervently believe, and upon which we must vigorously act. There is no other route to success.” Do we fervently believe that we, as front-line eye care providers, can help prevent glaucoma blindness? Do we fervently believe that our comprehensive eye health evaluation can be transformed into highly sensitive glaucoma screening exams? I do! And here is why we should, and how we can, vigorously A.C.T. to practice medical optometry in glaucoma and achieve these goals!

AWARENESS

Glaucoma is the leading cause of irreversible blindness in the world. In 2013, the estimate of those age 40 to 80 with glaucoma was 64.3 million, believed to increase to 76 million in 2020 and 111.8 million in 2040.1

Studies suggest half of glaucoma patients are unaware they have it.
Image courtesy of Dr. April Jasper

Despite this increasing prevalence, glaucomatous symptoms and VF defects are usually difficult for the patient to detect until the disease enters advanced stages.2 In fact, population studies suggest that as many as half of those who have glaucoma are unaware they have the disease.3

However, recent studies reveal that loss of peripheral vision is not the most common glaucoma symptom reported, and that glaucoma patients do not commonly see black areas in their field of view. These studies provide, “. . . evidence from patients themselves to contradict the common depiction of the visual symptoms of glaucoma: the end of a black tunnel.”4,5

By better understanding what glaucoma patients truly see, we, as a profession, can more accurately inform the public and, thus, increase its awareness of this condition. This, in turn, enables us to diagnose glaucoma early.

CLINICAL FINDINGS

In addition to increasing public awareness, consistently looking for specific characteristic clinical findings will prompt this awareness within our profession and help us to vigorously act on our goals. During each exam, we should look for “characteristic acquired atrophy of the optic nerve,” such as:6

  • Diffuse or focal narrowing, or notching, of the optic disc rim, especially at the inferior or superior poles.
  • Progressive narrowing of the neuroretinal rim with an associated increase in cupping of the optic disc.
  • Diffuse or localized abnormalities of the parapapillary retinal nerve fiber layer, especially at the inferior or superior poles.
  • Disc rim, parapapillary RNFL or lamina cribrosa hemorrhage.6

Consistently looking for these characteristic clinical findings helps transform our comprehensive eye health evaluation into highly sensitive glaucoma screening exams.

State-of-the-art diagnostic testing aids in our ability to identify “characteristic acquired atrophy of the optic nerve,” but such device integration can throw a wrench in practice efficiency.

To explain how to go about this efficiently, Dr. Shannon Steinhäuser tackles this topic on p.20.

TREATMENT TAILORED

Regarding those patients with glaucoma who need treatment, T. Realini proposed three main prognostic groups:7

  1. Those who do well no matter what we do.
  2. Those who will do poorly no matter what we do.
  3. Those whose long-term outcomes may depend on our management choices.

The latter of the three groups is both our opportunity and our responsibility. As each person is unique, treatment is both a science and an art. The “Whom to Treat Graph,” created by the European Glaucoma Society, represents different patients of different ages in different glaucomatous stages.8 The guiding principles within this graph, and in treating our patients, is that early diagnosis is key to preventing visually significant progression, and that we tailor the treatment to the age of the patient and the stage of the disease. In other words, younger patients with more advanced glaucoma may need more aggressive treatment, whereas a patient diagnosed very late in life with very early glaucoma may be able to be monitored closely without treatment after sufficient testing shows reliable visual stability.

As we seek to tailor treatment, it is helpful to remember that the “. . . primary goal of glaucoma therapy is to slow visual deterioration such that the patient experiences no symptoms from the disease during the course of his or her lifetime. . . ”9 and that, “treatment is generally indicated when the risks of progressive disease outweigh the risks and potential side effects of treatment.10

As of late, there has been a great deal of discussion regarding how to manage patients who require a second glaucoma medication, including when to start one, follow-up care and when to refer. Dr. Mike Cymbor discusses this hot topic on p.22.

THE BOTTOM LINE

Let’s A.C.T. vigorously through increased public and professional awareness, consistently looking for characteristic clinical findings and providing treatment tailored to these patients. By fervently believing in these goals and passionately acting on them, we can diagnose glaucoma early and detect progression sooner. An additional benefit: We can protect our patients and ourselves while doing it: This is something Dr. Gilbert-Spear covers in her article on legal considerations, which can be found on p.28.* OM

* An article on co-managing glaucoma patients, by Nathan Lighthizer, O.D., will be published at a later date. Also, see “Co-Managing MIGS,” by Justin Schweitzer, O.D., on p.40.

REFERENCES

  1. Tham YC, Li X, Wong TY, Quigley HA, Aung T, Cheng CY. Global prevalence of glaucoma and projections of glaucoma burden through 2040: a systematic review and meta-analysis. Ophthalmol. 2014; 11: 2081-90.
  2. Weinreb RN, Aung T, Medeiros FA. The pathophysiology and treatment of glaucoma: a review. JAMA. 2014; 18: 1901-11.
  3. Hennis A, Wu SY, Nemesure B, Honkanen R, Leske MC. Awareness of incident open-angle glaucoma in a population study: the Barbados Eye Studies. Ophthalmol. 2007; 10: 1816-21.
  4. Hu CX, Zangalli C, Hsieh M, et al. What do patients with glaucoma see? Visual symptoms reported by patients with glaucoma. Am J Med Sci. 2014; 5: 403-9.
  5. Crabb DP, Smith ND, Glen FC, Burton R, Garway-Heath DF. How does glaucoma look?: patient perception of visual field loss. Ophthalmol. 2013; 6: 1120-26.
  6. Primary Open Angle Glaucoma. Preferred Practice Pattern. American Academy of Ophthalmology web site. https://www.aao.org/preferred-practice-pattern/primary-open-angle-glaucoma-ppp-2015 . Published November 2015. Accessed January 8, 2019.
  7. Realini T, Fechtner R. 56,000 ways to treat glaucoma. Ophthalmol. 2002; 11: 1955-6.
  8. Terminology and Guidelines for Glaucoma. European Glaucoma Society: 4th Edition http://www.icoph.org/dynamic/attachments/resources/egs_guidelines_4_english.pdf . Published June 2014. Accessed January 2, 2019.
  9. Chang RT, Singh K. Glaucoma Suspect: Diagnosis and Management. Asia Pac J Ophthalmol. 2016 (1): 32-7.
  10. Consensus 7: 7th Consensus Meeting: Medical Treatment of Glaucoma. World Glaucoma Association: The Global Glaucoma Network. https://wga.one/wga/consensus-7/ . Published May 2010. Accessed January 8, 2019.