An unusual case of presbyopia

This well-dressed, well-groomed 42 year old woman came to my office complaining about blurry near vision for the past week. Her vision was 20/20 in each eye without any correction for distance. At near she did have difficulty and required a +1.75 add to read 20/20. Her eyes were healthy otherwise. I came to the only diagnosis that is presbyopia and educated her on this subject. 

She never wore glasses before and had always had good vision. She was quite depressed about the prospect of aging and could not believe that this happened to her.

To me it’s such a normal diagnosis, I did not think twice about it. Too bad this happened to her, but won’t this happen to everyone eventually?

I gave her a prescription of progressive lenses and asked to see her again in 1 year.

4 days later, she came to my office again. The appointment note said to re-evaluate vision. I was surprised and annoyed – why wouldn’t people accept the fact that they are getting older?

She sat down and started with “ Doctor, I have some good news that will change the prescription you gave me last time.” 

“What kind of good news will that be?” I thought to myself.

“My husband found this patch behind my ear that I forgot to take off after our vacation…”

“Oh my god” I said to myself silently. Of course it’s the scopolamine patch that everyone forgets about, which then gets absorbed by the skin and works to knock out the accommodation of the eyes, leading to the blurry near vision.

So the mystery is solved. This is not a usual case of presbyopia after all. My patient is a victim of drug-induced cycloplegia. 

She does have some eye strain after using computers for a long time. So I gave her a prescription of +1.00 add for near work as needed. I did tell her about the OTC readers, but she preferred prescription glasses.

Reflecting back on her case, her symptoms were newly onset, almost sudden onset, this is kind of a red flag, because presbyopia comes up gradually. Further, she’s not a latent hyperope, so +1.75 add was too high for her age. It’s her age that fooled me. If she were 20 years old, I would have investigated further.

Lesson learned: if accommodation is not what it should be, always ask about scopolamine patch. 

Accommodative insufficiency and convergence insufficiency

by Juan Ding, OD, PhD

I will try to write about one interesting eye case that I see each day. This is the first of the series.

A pretty woman with meticulous makeup (at least for me) in her early 40s complained about difficulty reading and seeing distance. Also had bouts of double vision a few months ago. She has a history of bipolar disorder, hypothyroidism and alcohol use, and goes in and out of rehab for alcohol problem.

 

This is the second time I see her. I saw her 3 weeks ago for the first time. As in any comprehensive eye exam, when I saw her, she’s already been worked up by the technician with her pupils dilated. Unable to make her see 20/20 with refraction, yet with a complete normal eye exam otherwise, I suspected a functional problem. So here she is again today, sitting in my chair, only able to see 20/60 letters for distance, and 20/100 letters at close up. Looking at her auto-refractor reading, I know right away that she will not respond to phoropter refraction. So I did the good old trial frame. With +0.25 D of astigmatism correction and +0.25 of sphere, she’s seeing the 20/20 line. Makes no sense even for a 70 year old to see so poorly with such a minor prescription. For near, she requires a +2.00 add, which people usually don’t need until 55 years and older.

 

I then did other tests to find out that her accommodation is indeed non-existent, and the ability of her two eyes to converge and diverge is also minimal.

 

I tried two pairs of glasses on for her, one for distance and one for near, and she’s comfortably seeing everything clearly. So I gave her the glass prescription, and ask her to come back if her vision is not improved with glasses.

 

My diagnosis for her is accommodative insufficiency and convergence insufficiency. These are functions of the eyes to focus and to look at objects at the same point, respectively. I have seen quite a few young women with these issues, and many of them with a psychiatric disorder such as bipolar, depression or anxiety. However, the visual functional deficit is not a psychological one, their eyes truly cannot perform, and glasses can usually help.

 

It has been shown that certain psychiatric medications such as ritalin can lead to accommodative insufficiency which makes convergence insufficiency worse (http://www.pressvision.com/pdf/hong_press.pdf). It is not known whether the medications that these patients are usually on, or their psychological issues, contribute to their accommodative and vergence dysfunction. Maybe both. Maybe another underlying cause results in their psychological and eye issues.

 

Common symptoms of accommodative insufficiency include:

  • difficult to focus,
  • blurry vision (especially when reading, using computer or phone)
  • eye strain

Common symptoms of convergence insufficiency include

  • double vision (especially when reading, using computer or phone)
  • eye strain.

 

Treatment for both:

  • Wear glasses: sometimes bifocals or progressive addition lenses are needed, and sometimes prism may help further.
  • Vision therapy: this is a set of individualized eye exercises that an optometrist prescribes and trains with motivated patients.