Glaucoma refers to a constellation of diseases of the eye that cause the progressive damage and ultimate disintegration of the optic nerve due to an increase in intraocular pressure built up as a result of blocked drainage canals. Untreated, glaucoma can lead to total blindness.
The population groups most likely to develop glaucoma include older adults, people with myopia, diabetes or cardiovascular disease, and people of Latino or African-American heritage. Those with a family history of the disease may also be at more risk. Statisticians note that close to two percent of all adults over age 40 will develop primary chronic glaucoma.
The most important thing an individual can do to prevent glaucoma is to have regular eye exams. Timely diagnosis and treatment can often preserve vision. While treatment can halt the progression of the disease, it cannot reverse any damage, such as blind spots and loss of peripheral vision, that has already occurred.
Here are a few things about the history of glaucoma that may be of interest:
1. The ancient Greeks wrote about it.
People have known about glaucoma for thousands of years. In writings attributed to the Greek physician Hippocrates, he described glaucoma as a condition typically occurring in older adults. Etymological sources point to the word “glaucoma” entering the English language in the 1600s, derived ultimately from a Greek word generally meaning “a clouding of the lens.” The Greek word “glaukos” may have originally referred to a silvery grayish or sea-green color, while “omma” meant “the eye.”
2. A British physician correlated glaucoma with increased eyeball tension.
The early 17th-century British physician Richard Banister was a pioneer in ophthalmology and defined glaucoma as a disease separate from cataracts. In 1622, he added to medical literature by publishing a treatise on eye-related diseases. This text also contained his observations of patients who had sometimes experienced no improvement in their vision and continued to exhibit a hardening of the eyes after having their cataracts removed.
3. Sir William Lawrence first used the name “glaucoma” in the 1800s.
Throughout the 18th and 19th centuries, doctors routinely failed to correctly diagnose glaucoma until the disease had reached an advanced stage, by which time it had completely robbed patients of their vision.
In 1832, the ophthalmic surgeon Sir William Lawrence wrote “A Treatise on the Diseases of the Eye.” This major work provided the first comprehensive synopsis of glaucoma symptoms, and was the first to actually use the terms “glaucoma” and “acute glaucoma” to describe the disease.
4. William McKenzie was the first person to prescribe a surgical treatment.
In the 19th century, William McKenzie prepared an influential textbook on ophthalmology, in which he gave descriptions of both chronic, or open-angle, glaucoma, and the acute, or angle-closure, form of the disease. McKenzie was first to outline a surgical method to relieve the hardness of the eye that comes with glaucoma.
5. The invention of the ophthalmoscope helped physicians diagnose glaucoma.
After physicist Hermann von Helmholtz introduced his new invention, the ophthalmoscope, doctors were able to see that the same type of excavated optic nerve destruction was visible in multiple types of glaucoma. This led to an increased ability to quickly diagnose the condition.
6. Albrecht von Graefe performed the first iridectomy.
Often cited as the first modern father of the science of ophthalmology, Albrecht von Graefewas an early adopter of the use of the ophthalmoscope. In 1856, he achieved the first-ever successful glaucoma surgery by performing an iridectomy — surgical removal of part of the iris — to lessen intraocular pressure in a case of angle-closure glaucoma. The iridectomy showed itself to be crucial in preventing future attacks of acute glaucoma.
It was not until the 20th century that physicians completely understood the reasons for the success of von Graefe’s operation. By the 1920s, physicians realized that when the aqueous humor in back of the iris builds up abnormally, it pushes the iris forward and causes a blockage.
7. Modern drug therapies emerged in the late 19th century.
In 1875, the drug pilocarpine became the first pharmaceutical treatment for glaucoma. Physicians continue to use the drug to address not only glaucoma, but also ocular hypertension and other pressure-related eye conditions. Over succeeding years, additional drugs to relieve intraocular pressure entered the market. These include eserine, as well as beta blockers and epinephrine.
8. New technology is leading to treatment innovations.
Supplementing much older diagnostic devices, such as a Schiøtz indentation tonometer to measure intraocular pressure, and the gonioscopy procedure, which lets physicians examine the anterior part of the eye to check whether fluid is draining properly, today’s treatments take a variety of forms.
One common initial glaucoma treatment involves medicated eye drops. Many patients not helped by drops undergo laser treatment or surgery.
Modern physicians also perform outpatient laser iridotomies without having to make an incision in the eye. This procedure helps patients avoid the type of risks prevalent in traditional types of surgeries and allows them to recover almost immediately.
Another recent surgical remedy is an operation called a trabeculectomy, in which doctors cut a small drainage hole in the white of the eye. One minimally invasive — and less risky — surgery involves implantation of a minute shunt designed to drain excess fluids.
