"What is glaucoma?” “What causes glaucoma?” “How do you treat glaucoma?” Patients, family members, and/or friends usually ask one (or all) of these questions. Because patients need to both understand and buy into the seriousness of the disease to comply with treatment and follow-up appointments, the optometrist must deliver simple answers. 

What is glaucoma?
“Simply, glaucoma is nerve damage. Specifically, glaucoma is characteristic structural damage to the optic nerve,^1-15 which communicates images from the retina to the brain. Glaucoma results in eventual associated correlating and irreversible defects in one’s field of vision.^15-19 The condition is chronic, unstable, and progressive, so it must be monitored closely, tested frequently,^20-23 and treated
sufficiently.^25-33”

What causes glaucoma?
“Glaucoma may be caused by abnormal eye pressures, which are unique to each patient.^33-39 Eye pressure is a measurement of the fluid within the eyes. Additionally, poor circulation to the eye or biochemical changes within the body may lead to characteristic structural damage to the optic nerve,^1-15 with eventual associated correlating and irreversible defects to one’s visual field.^15-19”

How is glaucoma treated?
“The best way to treat glaucoma is to lower abnormal eye pressures through prescription eye drops, laser procedures, and/or surgeries – whichever treatment is most effective, tolerable, and
sustainable for the patient.^{24, 26-28, 35, 37, 39} Additionally, we are learning that lifestyle⁴⁰ makes a difference in both the diagnosis and prognosis of glaucoma. Therefore, eating healthy.^41-45 staying active,⁴⁶ not smoking,^47-50 limiting stress through mindfulness/meditation,^{39, 51-52} preventing poor circulation from blood pressure that may be too low or too high,^47,54-62 and treating risk factors, such as sleep apnea ^47,63,64 may also help prevent or slow progressive glaucomatous damage.”

A bonus question
Occasionally, a patient asks me why I have a particular interest in glaucoma. I am happy to reply that I find the disease to be both challenging and rewarding. It is continually challenging trying to better understand why glaucoma develops in some individuals, determining who/when to treat, and ever-refining how to provide effective, tolerable, and sustainable treatment over the course of their disease. Furthermore, from the time of diagnosis, this chronic, unstable, and progressive disease is associated with both short-term and long-term decisions, which must be made at every visit. These decisions, in turn, directly affect (hopefully positively) visual prognosis years down the road. It is rewarding (when possible) to help prevent functional vision loss by diagnosing glaucoma earlier and detecting progression sooner. OM

References 

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31. Susanna R Jr, De Moraes CG, Cioffi GA, Ritch R. Why Do People (Still) Go Blind from Glaucoma?. Transl Vis Sci Technol. 2015;4(2):1. doi: 10.1167/tvst.4.2.1.

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33. Kass MA, Heuer DK, Higginbotham EJ, et al. The Ocular Hypertension Treatment Study: a randomized trial determines that topical ocular hypotensive medication delays or prevents the onset of primary open-angle glaucoma. Arch Ophthalmol. 2002;120(6):701–830. doi: 10.1001/archopht.120.6.701.

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38. Sommer A, Tielsch JM, Katz J, et al. Relationship between intraocular pressure and primary open angle glaucoma among white and black Americans. The Baltimore Eye Survey. Arch Ophthalmol. 1991;109:1090-1095. doi: 10.1001/archopht.1991.01080080050026.

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41. Tribble JR, Hui F, Jöe M, et al. Targeting Diet and Exercise for Neuroprotection and Neurorecovery in Glaucoma. Cells. 2021;10(2):295. doi: 10.3390/cells10020295.

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45. Ramdas WD. The relation between dietary intake and glaucoma: a systematic review. Acta Ophthalmol. 2018;96(6):550-556. doi: 10.1111/aos.13662.

46. Tribble JR, Hui F, Jöe M, et al. Targeting Diet and Exercise for Neuroprotection and Neurorecovery in Glaucoma. Cells. 2021;10(2):295. doi:10.3390/cells10020295. 

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64. Yu BE, Cheung R, Hutnik C, Malvankar-Mehta MS. Prevalence of Obstructive Sleep Apnea in Glaucoma Patients: A Systematic Review and Meta-analysis. J Curr Glaucoma Pract. 2021;15(3):109-116. doi: 10.5005/jp-journals-10078-1301.

AUSTIN LIFFERTH, OD, FAAO is clinical editor of Optometric Management. He practices at Center for Sight, is a member of the Optometric Glaucoma Society, and a Glaucoma Diplomate of the American Academy of Optometry. For additional glaucoma cases, you can also follow Dr. Lifferth on his Instagram account: glaucomaqd. Email him at glaucomaqd@yahoo.com.