Glaucoma is the neurodegenerative disorder of the optic nerve. The disease can cause impairment to the optic nerves, which may lead to incurable blindness. The optic nerves are made up of millions of thread-like nerve fibers. The major function of optic nerves is to carry visual information from eyes to the brain. Retinal ganglion has a significant role in transmitting visual information. So any deleterious on these nerves fibers can result in serious consequences in the normal function of eyes. This is the reason for glaucoma, often referred to as a multifactorial and complex disease. The precise mechanism of glaucoma is poorly understood and the reasons contributing to its progression have not been fully described.
Is Glaucoma Serious?
According to WHO, globally, glaucoma is the second leading cause of blindness. At present, 60.5 million cases of glaucoma exist in the world. Asians particularly women’s affected lot when compared to men. A study says that there will be 79.6 million cases of glaucoma by 2020. It is a serious threat to aged people particularly above 40. One of the most shocking facts is half of the glaucoma affected people live without knowing that they have this disorder.
Open-angle glaucoma is the most usual form, which is referred to as a silent threat. No symptoms in the initial phase but later the blindness progress in the peripheral sides of the eyes. If untreated the blindness may invade completely. Angle-closure glaucoma is more severe form than open-angle. It is associated with pain, dizziness, fuzzy vision, irritation, reddishness, and dilated pupil. It may be acute or chronic form. In angle-closure glaucoma, the beginning of symptoms is unexpected and causes pain. It is considered as a medical emergency and advanced surgery is preceded to prevent complete loss of vision.
Glaucoma is an umbrella term for several diseased conditions. There are other forms of glaucoma other than open and closed-angle glaucoma. Normal-tension glaucoma also known as low-tension glaucoma, secondary glaucoma, pseudoexfoliation glaucoma, pigmentary glaucoma, primary juvenile glaucoma, and uveitic glaucoma are some of the different types of glaucoma. Nerve damage and increased ocular pressure are seen most of the condition. Absolute glaucoma is the most severe phase and end stage of all types of glaucoma: severe pain in the eye with complete absence of vision, lack of pupillary light reflex and pupillary response, and stony like deposition appearances.
High intraocular pressure leads to glaucoma. The intraocular pressure main function is the formation of aqueous humor from the ciliary of the eyes and its drainage via the trabecular meshwork. The flow of the humor is decreased through the trabecular meshwork, due to the optic nerve degeneration. Thus the obstruction causes loss in vision with/without pain. Degeneration of the bundle of optic nerves often consequences in “cupping”. Cupping makes the vision injury and has the characteristic of optical disc like appearance.
The pattern of causing blindness among different races is unclear. In western countries, major glaucoma cases are open-angle particularly African-American and Hispanic people are more susceptible to this form of glaucoma. Caucasians as well are more susceptible to glaucoma blindness. Native Alaskans are at higher risk of angle-closure form glaucoma and Japanese descents are much more probable to develop low-tension glaucoma.
If the patients are diagnosed and treated earlier, the progression of the disease can be stopped or slowed down with the help of prescription, laser treatment, or surgery. The ultimate aim of the ophthalmologist is to decrease eye pressure which in turn reduces the vision of the loss. In this present century, due to several advancements in science and technology, different classes of drugs are available which are effective for the early phase of glaucoma. Laser treatments are effective in both forms of glaucoma i.e., open-angle and closed-angle. Canaloplasty, glaucoma drainage implants, trabeculectomy, and laser-assisted non-penetrating deep sclerectomy surgeries are some of the advanced treatment for patients with glaucoma to alleviate intraocular pressure.
- National Eye Institute. (2021). Facts About Glaucoma. https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/glaucoma
- American Academy of Ophthalmology. (2021). What Is Glaucoma? https://www.aao.org/eye-health/diseases/what-is-glaucoma
- Mayo Clinic. (2021). Glaucoma. https://www.mayoclinic.org/diseases-conditions/glaucoma/symptoms-causes/syc-20372839