The Challenge: Can you figure out what is causing a 68-year-old woman to lose her vision over the course of several months?
Every month the Diagnosis column of The New York Times Magazine asks Well readers to take on a difficult case and offer their solutions to a real-life medical mystery. This month the story revolves around a healthy 68-year-old woman who became fatigued and anemic — and then blind. We will provide you with many of the notes and tests from the doctor who figured out what was wrong.
The first reader to provide the diagnosis gets a signed copy of my book “Every Patient Tells a Story” and the satisfaction of solving a tough tough case.
Blurred Lines
The first hint the 68-year-old woman had that something was really wrong was how frequently she had to enlarge the font on her computer. As a software analyst who spent most of her day in front of a screen, she knew that sometimes, usually in the late afternoon, a larger font was easier on her eyes. But recently it hadn’t always been at the end of the day when the words and letters blurred. She had to enlarge her fonts every couple of days. She thought it might be the screen — it was old and maybe not as sharp. But a new and larger desktop display did not help.
Completely Normal but Nearly Blind
The woman went to see her eye doctor. She’d always had pretty good vision, though she had needed glasses for close work for a long time. Now things had changed. Her vision was much worse — though of course she didn’t need a doctor to tell her that. He examined her eyes carefully to see what had changed. She had no cataracts. No sign of glaucoma. Her retinas were fine. Indeed, on examination, her eyes looked perfectly normal.
If it wasn’t her eyes, then it had to either be the nerves that carried the information from the eye to the brain or the vision center of the brain itself. The doctor ordered an M.R.I. It, too, was perfectly normal.
Meanwhile her vision continued to deteriorate. Within days she was unable to distinguish faces at a distance. Within weeks, even close up, the faces of those she knew and loved became indistinguishable. Routines of normal life became difficult, then impossible. She could distinguish light from dark but little else. She had to rely on her husband for almost everything. She could no longer drive, no longer cook, no longer even plug in her own hair dryer.
The Patient’s History
At this point her eye doctor referred her to Dr. Thomas Slamovits, a neuro-ophthalmologist — a specialist in disorders affecting both the brain and the eye — in Ridgewood, N.J.
The anxious woman described to Dr. Slamovits how her vision had worsened over the course of just a few months. She’d had no pain in her eyes, no headaches, no body aches. Her only other symptom was that she’d felt a little more tired for the past few months. She’d been diagnosed with anemia earlier that year. A gastroenterologist scoped her up and down but didn’t find anything wrong. A half dozen blood tests were ordered, and none were revealing.
The labs ordered by the internist and the gastroenterologist can be seen here.
Other than this, the woman had always been in good health. The only medicine she took was a multivitamin. She had been a smoker but quit the year before. She rarely drank. She’d been pretty active until recently, when she felt too tired to do much more than go to work.
On exam, Dr. Slamovits noted that even with her glasses on, she could see at a distance of 20 feet only what others could see standing much further away, at 120 feet. And she was completely colorblind. The central part of her vision was gone, and what she could see, she saw mostly with her peripheral vision.
Although both eyes were affected, the left seemed a little worse than the right, since that eye didn’t respond correctly when a bright light was shined into her eyes. And yet, with even close examination, he could see nothing wrong.
Dr. Slamovits figured that there was some injury to the nerve that carried the information from the eye to the visual center of the brain. He repeated the M.R.I., asking for detailed images of the visual tracks; again, it was normal.
You can see the letter Dr. Slamovits sent the original ophthalmologist here.
You can see two views of the M.R.I. here.
Dr. Slamovits sent her to a colleague to get highly specialized testing of the nerves leading into the eye. Those tests revealed that the optic nerve was damaged.
You can see the report from the specialist here.
Weighing the Diagnoses
So what could cause this kind of nerve damage without showing up on an M.R.I? The list was short and dotted with zebras.
There were a couple of autoimmune disorders — multiple Sclerosis (MS) and neuromyelitis optica (NMO) — that can attack both the optic nerve and the spinal cord. These diseases, though, usually caused tingling, numbness or transient weakness in addition to the loss of vision, symptoms this woman didn’t have. But they had to be considered.
In addition, there is an inherited disease known as Leber’s hereditary optic atrophy that can cause this kind of abrupt blindness in middle age. It would be uncommon, since Leber’s usually affects young men in early adulthood, but it has been described in women as well. And there are certain vitamin deficiencies, especially in B vitamins, that can affect vision. Dr. Slamovits ordered the necessary tests to look for these possibilities.
You can see the results of those tests here.
Solving the Mystery
When all the tests came back negative, Dr. Slamovits was at a loss. Something had damaged this woman’s optic nerves. He’d checked out the usual suspects. What was left?
Dr. Slamovits finally figured it out, and his diagnosis saved his patient’s vision — and perhaps her life. My challenge to you is to figure out what has robbed this woman of her vision.
Rules and Regulations: Post your diagnosis and any questions you may have in the Comments section. The correct answer will appear on Friday on Well. The first person to answer will receive a copy of my book and that warm, wonderful feeling you get from solving a mystery. The winner will be contacted. Reader comments may also appear in a coming issue of The New York Times Magazine.