Dr. Nathan Steinle spent 14 years in college and medical school studying the retina, a postage stamp-size layer in the eyeball. The retina is a tiny layer at the back of the eyeball containing cells that trigger nerve impulses that pass via the optic nerve to the brain, where a visual image is formed.
The eye is his life’s work, and he finds that people hold fast to myths about the eye and eyesight. Speaking to about 40 people gathered at a recent Lompoc Hospital District Foundation lecture, Dr. Steinle laughed as he explained the reality behind a number of eye-related myths.
No, he said, you can't go blind if you read in dim light. And you definitely can't “wear your eyes out” by using your vision too much. And even some emergency room doctors have asked him whether a contact tens can be “lost behind the eye.” No, that’s not true either.
And finally, he doesn't foresee a day when surgeons would be able to do a complete eye transplant. There are just too many complicated parts, including more than 1 million fibers that connect the eye to the optic nerve.
In discussing the eye, Dr. Steinle was able to inform about the main diseases he deals with in his numerous offices throughout California —— including one in Lompoc. Dr. Steinle and his associates are specialists in treating diabetic Retinopathy, retina detachments, and macular degeneration.
“If you think about it, you use your eyes every single day of your life,” he noted. “Most of the time you take it for granted. They just work, and you don't think about them until it’s a problem. Once it’s a problem, you think about them more, and think ‘‘How the heck am I going to get through this?”
The macula is the center part of the retina. “That’s where the light comes directly into and hits your macula. That’s also where you have the best-detailed vision.”
Some 24,000 Americans blinded each year by Diabetic Eye Disease or diabetic retinopathy. Dr. Steinle treats many patients with this issue. “The frustrating thing about diabetes is it can strike a 20-year-old, a 40-year-old, and can really cost them a lot of working years.”
Diabetic Retinopathy affects the tiny blood vessels of the retina. Retinal blood vessels can break down, leak, or become blocked- affecting and impairing vision over time. In some people with diabetic retinopathy, serious damage to the eye can occur when abnormal new blood vessels grow on the surface of the retina.
There are two risk factors —— duration and severity. He'll ask patients how long they've had diabetes, and he'll ask for their Hemoglobin A1C level or the long-term snapshot of blood sugars.
“If you remember anything from tonight, remember one number —— Hemoglobin A1C of 7. Lucky number 7. If you keep it below 7, you'll usually be pretty darn good with your eyes.”
He said that with people who have blood sugars that are way to high, as blood circulates through blood vessels, it can create leaks or rust.
“The higher the blood sugars the more rust in the back of your eye,” he said. “The more rust, the more they’’re going to bleed. If you get lots of bleeding, it can really impact your vision.”
In his practice, he can make small incisions on the white part of the eye, and suction out the blood. He'll then apply a laser to the hemorrhages to cauterize them so they won't come back. He says that while it may seem “barbaric,” he performs the procedures six to eight times each week. Age-related macular degeneration is another issue he works with in his practice. It is the leading cause of vision loss in older American adults.
Macular degeneration takes out the central vision area. Patients, he said, often disclose that things look like a big blur, or if they’’re looking at a flag pole it may seem wiggly, or if they’’re looking at a door it will appear as if the door jack is crooked. “That’s because it’s affecting the center part or macula,” he said.
There is both wet and dry macular degeneration. Of the cases in the U.S., about 90 percent are of the dry kind. The risk factors include being caucasian, female and elderly. He compared the dry type to age spots. “You get those same age spots in the back of the eye,” he said. “They just kind of blur your vision. You can still see, you can still drive, but maybe you’’re not seeing the smaller print. Age spots change the vision a little bit.”
A popular treatment is an injection designed to block a molecule called Vascular Endothelial Growth Factor or VEGF. VEGF causes the growth of leaky blood vessels in patients with the wet form of macular degeneration. Photodynamic therapy, which uses a cold laser to treat select areas of the retina and laser surgery, which uses a hot laser to treat leaky blood vessels.
Cataracts, he said, is like having to wear sunglasses all the time. People with cataracts complain that things are gray and blurry and it’s difficult to drive at night. A cataract is a clouding of the normally clear lens of your eye.
“It really affects your vision,” he explained. “For those of you who have had cataract surgery, you get a custom lens in your eye. So we take a gray foggy natural lens and replace it with an acrylic, a specialized type of plastic in that same capsule. The beautiful thing is you can design the lens however which way you want to bend light. So the lens you get is as different as the lens the next person gets. And different between the two eyes. We can correct for all your glasses needs with that cataract lens today.”
He said cataract repair is by far the most common surgery currently done in the U.S. Glaucoma is another issue treated by Dr. Steinle. Glaucoma is a disease that damages the eye’s optic nerve. It typically occurs when fluid builds up in the front part of the eye. That extra fluid increases the pressure in the eye, damaging the optic nerve.
This problem affects a person's peripheral vision, creating a type of tunnel vision, he said.
“The Hallmark of treatment for years and years and years have been drops,” he said. “Drops all lower pressure in the eye. There’s probably 40 types of drops. A doctor will determine which drop works for you. You can also do laser to filter more fluid out more quickly to reduce fluid.”
Dr. Steinle has been an investigator in a number of clinical research trials including the investigation of novel therapies for neovascular age-related macular degeneration, retinal vein occlusion, and diabetic retinopathy. Dr. Steinle is a Board Certified Ophthalmologist, and is a member of the American Academy of Ophthalmology, the Association for Research in Vision and Ophthalmology, the American Society of Retina Specialists, and the American Medical Association.