A young lady of 21 came to see me today. Her major complaint was that her right eye was bigger than her left. I asked her how long ago she first noticed this and her reply was one month. She was seeking a second opinion from me as the previous ophthalmologist could not help her.
I will call her Susan. Susan had no prior medical history, worked in the retail business, and was quite concerned about her right eye. She denied any pain or change in vision. I looked at her and did not notice a difference in the size of her two eyes. Sometimes an eyelid can be drooping and make that eye look smaller than the other. However her lids were symmetrically positioned. I measured he protrusion of her eyes from the bony orbits and did not find any asymmetry either.
I explained to Susan that there was no obvious difference in her eye size. She became quite animated and surprised. Her first response was "Are you serious?" I had her look in the mirror and she said the difference was obvious. Perhaps she was noting her pupil size, but she denied this. I asked one of my partners to look and he did not see a problem either. At this point Susan took out her cellphone and took a picture of her face. She promptly and emphatically held the camera's picture up to me to view and said "Do you now see the difference?"
Clearly some patients present challenges that my med school psychiatry rotations did not fully prepare me for. Though I tried to reassure her that whatever she saw was within the normal range , she would have none of that. I did what most doctors do in situations where the patient is no longer trusting our opinion: offered her another opinion with another ophthalmologist. That would be the third eye surgeon she would be seeing. I wish her well. Perhaps you might ask why I did not investigate further, for example, by getting a CT Scan of her eyes. Then I could show her there is no tumor or abnormality behind her eye. The problem is there is a cost associated with the scan which I could not justify. Even more importantly she would be exposed to unnecessary radiation. Sometimes as physicians the best we can do is try to reassure patients that their fears are not going to come to fruition.
Monday, September 22, 2008
macular degeneration
My long - standing patient, Mrs. R, came in today for her annual eye exam. She has macular degeneration. Unfortunately she noticed that she could no longer see in 3 dimensions. To me this meant she had lost depth perception. Her right eye vision was worse than 20/200, the definition of legally blind. Her left eye saw 20/20. You need both eyes seeing well in order to have fine depth perception. While it is true that I cannot make her see better out of her right eye, she can take steps to protect her remaining vision.
Step 1: Don't smoke!! Fortunately she does not.
Step 2: Wear sunglasses outdoors to protect the macula from ultraviolet radiation.
Step 3: Monitor each eye at least once a week by covering one eye at a time and viewing a piece of graph paper (we give this a fancy name - an Amsler Grid). If the patient notices a distinct change in the vision in one eye, wavy vision, areas missing, that does not improve over the day, she should seek evaluation as soon as possible.
Step 4: Eat a diet rich in antioxidants or take a daily multivitamin. My patient is on Ocuvite Preservision. This very high antioxidant formula is used when significant abnormalities of the macula are noted. It can slow the disease progression. It is not yet been shown beneficial for milder forms of macular degeneration.
Step 5: Do your best to stay in good cardiovascular health.
Mrs. R told me she gave up driving after nearly hitting someone recently. Though the law states based on her vision she can still drive, she is acting prudently.
If her vision in her left eye worsens, I would have the sight center work with her to optimize her remaining vision. Patients with macular degeneration want to know if they are going blind. Sadly, some do over time. However, there are newer treatments available for some patients that can be vision saving. Lucentis and Avastin are injected into the eye and have been a wonderful part of the ophthalmologist's armamentarium. These drugs have been available for 2 years or so. Many patients ask if they can be treated with them. However, they are used only for wet macular degeneration, not dry. Wet is a complication of dry and means new blood vessels are growing into the macula, leaking blood and fluid and rapidly threatening the eye sight. It is not good to have this condition but the above medications can help. They do not aid in the treatment of dry macular degeneration which most patients have.
Step 1: Don't smoke!! Fortunately she does not.
Step 2: Wear sunglasses outdoors to protect the macula from ultraviolet radiation.
Step 3: Monitor each eye at least once a week by covering one eye at a time and viewing a piece of graph paper (we give this a fancy name - an Amsler Grid). If the patient notices a distinct change in the vision in one eye, wavy vision, areas missing, that does not improve over the day, she should seek evaluation as soon as possible.
Step 4: Eat a diet rich in antioxidants or take a daily multivitamin. My patient is on Ocuvite Preservision. This very high antioxidant formula is used when significant abnormalities of the macula are noted. It can slow the disease progression. It is not yet been shown beneficial for milder forms of macular degeneration.
Step 5: Do your best to stay in good cardiovascular health.
Mrs. R told me she gave up driving after nearly hitting someone recently. Though the law states based on her vision she can still drive, she is acting prudently.
If her vision in her left eye worsens, I would have the sight center work with her to optimize her remaining vision. Patients with macular degeneration want to know if they are going blind. Sadly, some do over time. However, there are newer treatments available for some patients that can be vision saving. Lucentis and Avastin are injected into the eye and have been a wonderful part of the ophthalmologist's armamentarium. These drugs have been available for 2 years or so. Many patients ask if they can be treated with them. However, they are used only for wet macular degeneration, not dry. Wet is a complication of dry and means new blood vessels are growing into the macula, leaking blood and fluid and rapidly threatening the eye sight. It is not good to have this condition but the above medications can help. They do not aid in the treatment of dry macular degeneration which most patients have.
Sunday, September 14, 2008
cataract surgery after lasik
A popular misconception is that Lasik makes cataract surgery more difficult. Actually the surgery is identical. The problems arises in picking the new intraocular lens. Lasik surgery makes these calculations more difficult. Therefore, if the new lens is intended to correct one's distance vision so they still don't need distance glasses, the patient may end up myopic or hyperopic, essentially requiring glasses now to see well at distance. The normal measurements are dependent on accurately measuring the cornea's anterior curvature but lasik changes the relationship between the anterior and posterior curvature leading to inaccurate results. However, newer formulas have helped alleviate some of this difficulty. The most important advice I can give you, the patient, is have records of your lasik workup available for your cataract surgeon. This will allow your surgeon to be more precise in the new lens calculation.
Mr. H, a 47 year old man had Lasik surgery 5 years ago. Fortunately he had a wonderful result. A few months ago he developed blurred vison in his right eye. This made it difficult for him to drive, play golf, or even read at times. I saw him for the first time one month ago. He had a significant cataract. We discussed the difficulties in implant calculation. I was able to obtain the Lasik work-up measurements from elsewhere and use these numbers to calculate the implant power. I used a few different formulas.
On the day of the surgery, all went well. This was expected since I told him he had only a 2% chance of a complication. The real anxiety comes from learning what his vision is without glasses the day after surgery. Mr. H is a fairly non-emotional man. The day after surgery I walked into the exam room and asked him how he was doing. He said fine. That's all. Fortunately his vision was about 20/30 without glasses for distance. This bodes well. As his eye settles down in the next few weeks, I believe he will do well. If his vision were not good on the first day after surgery, I could attribute this to either a cloudy cornea from the stress of surgery, which will clear in the next few days, or that my calculations were off and he really will need glasses for good distance vision.
Bottom line, he can always be helped. We can discuss this in future posts.
Mr. H, a 47 year old man had Lasik surgery 5 years ago. Fortunately he had a wonderful result. A few months ago he developed blurred vison in his right eye. This made it difficult for him to drive, play golf, or even read at times. I saw him for the first time one month ago. He had a significant cataract. We discussed the difficulties in implant calculation. I was able to obtain the Lasik work-up measurements from elsewhere and use these numbers to calculate the implant power. I used a few different formulas.
On the day of the surgery, all went well. This was expected since I told him he had only a 2% chance of a complication. The real anxiety comes from learning what his vision is without glasses the day after surgery. Mr. H is a fairly non-emotional man. The day after surgery I walked into the exam room and asked him how he was doing. He said fine. That's all. Fortunately his vision was about 20/30 without glasses for distance. This bodes well. As his eye settles down in the next few weeks, I believe he will do well. If his vision were not good on the first day after surgery, I could attribute this to either a cloudy cornea from the stress of surgery, which will clear in the next few days, or that my calculations were off and he really will need glasses for good distance vision.
Bottom line, he can always be helped. We can discuss this in future posts.
Wednesday, September 10, 2008
lasik day
I still marvel at the technological advancements that have made this procedure, LASIK, better than ever. A femtosecond laser, that is called IntraLase, is used to etch a thin layer on the surface of the cornea. The goal is a flap that can be raised but is also hinged. This allows the Excimer Laser to remove tissue from the cornea and reshape it. I used to create the flap with a metal blade. Now, the laser creates the flap by separating layers of the cornea with air bubbles. Then a side cut is made with the laser to allow the layer to be lifted.
The advantage of the laser is precision and safety.
The excimer laser is driven by a wavefront measurement. Essentially, a measurement of the eye's optics is taken before the procedure, then transferred to the laser via a flash drive. The measurement is done bouncing a light beam off the back of the eye, and capturing the wave of light that exits the eye. This wave has been bent by the optical elements within the eye. Transferring the information from the wave of light to the excimer laser allows the laser to correct the refractive error of the eye. Essentially, this allows me to use an objective measurement of the eye, rather than the subjective refraction done in the office.
The advantage of the laser is precision and safety.
The excimer laser is driven by a wavefront measurement. Essentially, a measurement of the eye's optics is taken before the procedure, then transferred to the laser via a flash drive. The measurement is done bouncing a light beam off the back of the eye, and capturing the wave of light that exits the eye. This wave has been bent by the optical elements within the eye. Transferring the information from the wave of light to the excimer laser allows the laser to correct the refractive error of the eye. Essentially, this allows me to use an objective measurement of the eye, rather than the subjective refraction done in the office.
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