Chapters: 0:00 Intro 0:32 What causes nearsightedness? 1:01 Why can’t you see far? 1:20 When does nearsightedness usually begin? 1:42 What are symptoms of nearsightedness? 1:59 Can nearsightedness be corrected? 2:23 Is there a cure for nearsightedness?
Cataracts in the eye lens are a later-in-life reality that leads to vision problems for many people. This video shares describes what cataracts are, how they form, and warning signs to help you detect them early.
Chapters: 0:00 Intro 0:10 What are cataracts? 0:43 What are the warning signs of cataracts? 2:44 How are cataracts diagnosed? 3:04 Talk to your eye doctor
Often described as the silent thief of sight, glaucoma is the most common cause of irreversible blindness in the world. High pressure in the eye damages the optic nerve, first stealing peripheral vision (what you see at the corners of your eyes) and later harming central vision (what you see when looking straight ahead). Usually, people notice no symptoms until vision loss occurs.
Lowering high eye pressure is the only known treatment to prevent or interrupt glaucoma. But does everyone with higher-than-normal eye pressure need to be treated? A major long-term study provides some clues, though not yet a complete answer.
In the US, glaucoma affects an estimated three million people, half of whom do not know that they have it. An ophthalmologist can perform a comprehensive eye exam to determine if someone has glaucoma, or is at risk for developing it in the future due to high eye pressure (ocular hypertension). Research from the long-running Ocular Hypertension Treatment Study (OHTS) shows that some people with high eye pressure may never develop glaucoma, while others will.
Myopia, also known as short-sightedness or near-sightedness, is a very common condition that typically starts in childhood. Severe forms of myopia (pathologic myopia) are associated with a risk of other associated ophthalmic problems. This disorder affects all populations and is reaching epidemic proportions in East Asia, although there are differences in prevalence between countries.
Myopia is caused by both environmental and genetic risk factors. A range of myopia management and control strategies are available that can treat this condition, but it is clear that understanding the factors involved in delaying myopia onset and slowing its progression will be key to reducing the rapid rise in its global prevalence.
To achieve this goal, improved data collection using wearable technology, in combination with collection and assessment of data on demographic, genetic and environmental risk factors and with artificial intelligence are needed. Improved public health strategies focusing on early detection or prevention combined with additional effective therapeutic interventions to limit myopia progression are also needed.
At one time, replacement parts for the eyes must have seemed unimaginable. Nowadays, if the inner lens of the eye becomes clouded by a cataract, a routine surgery to swap it out with a new artificial lens restores vision.
But what happens if the outer lens of the eye (the cornea) becomes damaged or diseased? You can have that replaced, too. “It’s not as common as cataract surgery, but many people get corneal diseases after age 50 and may need a corneal transplant,” says Dr. Nandini Venkateswaran, a corneal and cataract surgeon at Harvard-affiliated Massachusetts Eye and Ear.
More than 49,000 corneal transplants occurred in 2021 in the US, according to the Eye Bank Association of America.
The cornea is a dome of clear tissue at the front of each eye, covering the iris and pupil, that acts as a windshield that protects the delicate eye apparatus behind it, and focuses light onto the retina, which sends signals that the brain turns into images (your vision).
You need this combo of windshield and camera lens to focus and see clearly. But many things can go wrong within the five layers of tissue that make up the cornea. That can make it hard to see and rob you of the ability to read, drive, work, and get through other activities in your day.
It may stem from a number of causes:
Cornea treatment depends on the type of problem you have and the extent of the damage. “It’s a stepwise approach. Sometimes wearing a specialty contact lens or using medications can decrease swelling or scarring in the cornea,” Dr. Venkateswaran says.
Cataracts involve the lens of the eye which is located just back of the cornea.
The lens is composed of evenly aligned collagen fibers which are progressively damaged by ultraviolet light as we age. Cataracts cause clouding of the lens and reduce visual acuity, as well as causing a stiffening and rigidity of the lens which keeps it from changing shape for close-up activities like reading.
If you live long enough, cataracts are almost inevitable and the main decision is when to get them corrected. With intraocular lenses, the operation has few downsides.
The halo around oncoming headlights disturbed my night driving, and was a major reason for me to get my cataracts removed.
I used to require glasses all the time, and took them off to read. Now I wear no glasses, and even reading is possible without glasses, since one of my eyes has a -1.5 diopter cylindrical astigmatism. You can ask for one Intraocular lens to be slightly nearsighted, if you wish to avoid needing reading glasses.
I prefer to use my corrective glasses to read, however.
—Dr. C.
Herpetic Keratitis is a viral infection of the transparent, frontmost part of the eye, the cornea.
Herpes 1 or 2 when rubbed into the eye from a cold sore, or contacted from somebody else with herpes, will often affect the cornea. The use of corticosteroid eyedrops or ointment will allow the disease to spread faster.
The symptoms are pain and redness of the eye and are a medical emergency, needing prompt treatment by your doctor to prevent scarring and blindness.
Antiviral eyedrops, such as valacyclovir, are used to treat ophthalmic herpes.
A related condition is ophthalmic zoster, caused by the varicella zoster virus. The VZ virus will produce chickenpox in unimmunized people, go into dormancy in the nervous system, and then resurface, if immunity wanes, as shingles. If the shingles occurs in the ophthalmic division of the trigeminal nerve, affecting the skin near the eye, the cornea will often be involved. Ophthalmic zoster is also treated by antiviral eyedrops.
The varicella zoster virus is closely related to the herpes simplex virus, and is a member of the same nasty family of viruses.
—Dr. C.
Keratoconus involves the cornea, the front most part of the eye, which becomes thin, and then can bulge out in ways that make correction with glasses difficult. It usually involves both sides although one side is worse. When it occurs only in one eye and not regularly followed, it can be difficult to diagnose and treat properly.
In keratoconus, there is a thinning of the cornea caused by collagen deterioration. This can be usually detected by an ophthalmologist with his slit lamp, which is a low magnification microscope.
Vision loss is always distressing, but arguably is even worse when it afflicts young people in the process of developing their identity, and interferes with schoolwork.
Keratoconus is usually begins in adolescence, progresses over 10 to 20 years, and stabilizes in the third decade of life.
There are a number of treatments depending upon the severity of the condition. In the beginning glasses suffice. Later on, a hard scleral contact lens can be used. There are treatments aimed at cross linking the corneal collagen and strengthening it. The worst cases require a corneal transplant.
The most important thing is to go promptly to a good eye doctor, preferably an ophthalmologist.
–Dr. C
If you can go the over-the-counter route, here are some tips.
Doctors Without Waiting Rooms 