
Photograph courtesy of Charles Retina Institute.
Dr. Jorge Calzada knows his patients dread a certain word so much they don’t even want to say it.
Blindness.
As an associate surgeon and president of the Charles Retina Institute, Calzada encounters this fear several times a day.
“Most people take their vision for granted,” he says. “They never consider that losing their eyesight might be something that could happen to them — until they come here, so there’s a real anxiety that has to be addressed.”
Born in the Republic of Panama, Calzada earned his medical degree from the University of Panama Medical School in 1996. He came to the U.S. to complete his residency at the University of Tennessee, then returned to Panama and joined one of the most respected ophthalmology practices in his home country. During his tenure in Memphis, he had encountered Dr. Steve Charles, founder of the Charles Retina Institute, who persuaded Calzada to join his staff as a vitreoretinal surgeon. He is also an assistant professor of ophthalmology at UT, and an attending physician at UT’s Hamilton Eye Institute. As founder of Panamerican Vitreoretinal Consulting, he regularly returns to Central America for lectures and surgeries.
This lifelong interaction with so many patients from different cultures has shown him that blindness is more than a medical issue. It carries a socioeconomic impact that can be devastating. “Vision loss decreases a person’s ability to make a living,” he says. “It also brings somebody else down with them because now you need someone to help that person, so you have this halo effect.”
People often associate blindness with old age — they think of an elderly person tapping a white cane as they venture down the sidewalk. But vision problems can appear at birth, and “one of the things that really gets to me is childhood blindness,” says Calzada. “It’s going to affect the whole life of that child, all the way into adulthood, and they will always need some kind of assistance. Getting that person to be independent is a very difficult thing.”
The human eyeball operates like a camera. An image enters the eye through the pupil, where the lens focuses that image onto the retina, the paper-thin layer of cells lining the back of the eye. Accidents (“running with scissors is a very real thing in my profession,” says Calzada), congenital malformations, and even rare genetic disorders can ruin, or even destroy, a person’s vision if the cornea, lens, or other physical structures of the eyeball itself are damaged. Even so, in many cases, injuries can be treated, and vision can be restored.
The prognosis is not always so good with disorders of the retina. Childhood blindness is often the result of a condition called “retinopathy of prematurity.” A child born weeks or even months before the normal nine-month gestation period is often hailed as a miracle baby, but all too often blood vessels in that baby’s eyes haven’t fully developed.
“When a premature baby is born, the center part of the retina, known as the macula, has blood vessels, but the outer part doesn’t,” he explains, showing a diagram of an infant’s eyeball. “The eye, trying to fix that lack of blood flow, creates abnormal blood vessels that grow like weeds around the edge of the retina. As these grow, they scar. And as they scar, they pull up the retina, and that’s basically the problem.” A distorted retina means distorted vision.
In some cases, Calzada explains that “if we’re able to catch the babies at just the right time, we’re able to save their vision” with injections directly into the eyeball that inhibit the growth of the abnormal vessels. “But the hard part is getting the right timing, because you only have a window of about three days to get it right.”
This means premature babies must be regularly monitored for this condition.
“We have to make sure to deliver the treatment at the proper time,” he says. “On a regular basis, we probably screen 30 or more babies every week, in the hospitals and here at the clinic. If they come in one or two weeks too late, the cat’s out of the bag.”
Over the years, dramatic improvements in medical technology, advanced treatment options, and more effective medications have reduced the risk of blindness for people of all ages. Unfortunately, science hasn’t made as much progress as Calzada would like to see in two important areas: diabetic retinopathy and macular degeneration.
Diabetes is more prevalent among a somewhat older population, and Calzada says, “We have so many treatments for diabetes, yet we clearly have an epidemic in this country of obesity, and along with that is an epidemic of diabetic retinopathy.” Diabetes is an insidious disease that can often cause no symptoms while it is damaging the pancreas, nervous system, and blood vessels, including the tiny vessels that nourish the retina.
“A type II diabetic must have their eyes examined upon diagnosis because most of the time they don’t know how long they’ve been diabetic,” says Calzada. “It just creeps up on them. We see patients who just got diagnosed, and we look into their eyes and they have advanced retinal disease.” In those cases, recovery may be too late; in others, the treatment is medication and surgery.
Macular degeneration is a leading cause of vision loss. It develops in two forms: wet and dry. The wet form, also called neovascular or exudative, cannot be cured — not at present, anyway — but it can treated. “These are patients that have abnormal growth of the vessels beneath the retina, which can scar, bleed, and cause all sorts of issues,” says Calzada. “But we have medications that are injected into the eye, which sounds bad but it’s really not if it’s done well.” Even so, he says, “you have to catch it in time, before there is significant scarring.”
The dry form, also called nonexudative, is bad news. “I have to tell patients that it’s like Alzheimer’s of the eye,” says Calzada. “It is a slow, withering damage of the retina, a slow atrophy that develops. These patients won’t lose their vision overnight, but it will be a gradual decline.”

“We want neurons that can regrow and reconnect the eye with the patient’s brain.” Photograph courtesy Charles Retina Institute.
The real problem with macular degeneration is that it affects a patient’s central vision. Their peripheral vision may be fine, but they can’t see anything clearly by looking directly at it. Simple tasks like reading or viewing a computer screen become impossible. Calzada had earlier mentioned how much patients dread hearing the term “blindness” and he says, “I just talked today with three patients with severe macular degeneration in the dry form, and there is nothing I can do for them.”
The positive news is that the field of ophthalmology, in general, has seen advances in many areas. “The amount of technology that we use on a day-to-day basis is really outstanding,” says Calzada. Instead of scalpels, lasers are being used routinely to “spot-weld” detached retinas or burn away scar tissue, and new computer imaging systems, such as the OCT (optical coherence tomography scan) “now give us the ability to look into the eye with a resolution of less than 10 microns, which is less than ten-thousandths of a millimeter. So we are finding disease that is truly beyond our ability to determine by looking into the eyes directly.”
On the surgical side, procedures are done with instruments the size of needles, so small that Calzada calls them “Barbie Doll instruments, which allow very delicate operations without big wounds and pain.” With better tools and better medications, “it’s almost like peanut butter and jelly, in the sense that the two work so well together.”
So what does Calzada hope for the future? For one thing, the biggest challenge is dealing with atrophy of the retina, from disease or age. “There’s a lot of research being done involving transplantation of retinal cells,” he says, “but it’s still experimental.” Calzada also hopes to see medications to control the formation of scars. “On the retina, even a small scar can cause a vision problem, but any medication that destroys scar tissue also destroys the retina.”
Ultimately, “what neurologists want is what we want — some way to regenerate nerve cells. Just like they want to reconnect the cells in a broken spinal cord, in a patient with optic-nerve disease we want neurons that can regrow and reconnect the eye with the patient’s brain.”
Although admitting that such things seem like something out of science fiction, he says, “Years ago, today’s technology also seemed like something out of the future.”
One aspect of his field especially troubles him: childhood blindness. “Many things we can fix now that we couldn’t before,” he says. “But years ago I promised myself: no more blind children. It’s still not possible — not yet — but it’s a promise I made to myself.”
Making an Instant Connection with Instagram
For years, scientists — from physicians to astrophysicists — have shared their research in two timeless ways: attending conferences, and publishing in medical and science journals. Social media has opened new platforms, and Dr. Jorge Calzada recently started a “little fun thing” — an Instagram account that now has more than 10,600 followers.
“I realized that there was not an account that deals with retinal disease,” he says, “so let’s see what happens.” The result: followers from the United States, Russia, China, South America, and Central America. Recent posts include text and photos on such topics as “Diabetic Traction Retinal Detachment,” “Retinal Scissors Delamination,” “Retinal Microaneurysm,” “Branch Retinal Artery Occlusion,” and “Vascular Pulsations at the Optic Nerve.”
“Medical education is still bounded by a certain degree of proximity between the teacher and student,” he says, “so how do you make an impact beyond the small circle around you? These are not the senior doctors, who don’t mess around with Instagram. These are young doctors who are craving information. It makes me feel good that there is some form of connection that happens in an international perspective.”
Follow Calzada on Instagram at jordical_retina.