Today’s guest blogger is Dr. Samantha Slotnick. Dr. Slotnick, is a Behavioral Optometrist practicing in Dobbs Ferry, NY at Terri Optics. She is also a Clinical Research Associate at the SUNY State College of Optometry in NYC.
Eye turns are a common problem affecting about 3% of the population.
Often, when patients with eye turns come to me, they are not aware of any non-surgical options to address their problem. Some of these patients have already had surgery, perhaps unsuccessfully, or they report that the surgery worked for a while, but “didn’t hold.” They’ve often been told in advance that they may need a second or third surgical procedure.
The problem with treating an eye turn (strabismus) with surgery alone is that strabismus is rarely a “muscle-only” problem. Especially after years of living with the eye turn, our highly adaptable brains come up with strategies for coping with information coming from two eyes which do not point in the same direction.
Among these strategies are suppression and anomalous projection (or anomalous correspondence).
-Suppression blocks out information from one eye, which protects the person from experiencing double vision. Suppression only occurs when both eyes are open. It takes energy to actively suppress information.
-Anomalous projection (or anomalous correspondence) trains the brain to match up information between the two eyes based on the way they are pointing, rather than on the way the original connections are made between the eyes and the brain. This allows the patient to retain some degree of stereopsis. (Stereopsis is 3-D vision derived from the two eyes seeing the world from slightly different vantage points.)
These two main “strategies” are very helpful for the person with an eye turn … until attempts are made to straighten the eyes. If surgery is used to straighten the eyes (by relocating muscle attachments), but no attention is paid to the brain’s “strategies,” there is a much lower potential for long term success.
Consider what would happen if the eyes were made to align (surgically), but suppression continued to block information coming from one eye. In many cases, without addressing this protective “strategy,” the brain does not learn to combine the information from both eyes. So, even though surgery moves the eyes so that there will be no conflict between the images from the right and left eyes, there is also no “glue” to keep the eyes aligned after surgery. In a case like this, the eyes may start to turn again, even after appearing like they were holding straight after surgery.
Now consider what would happen if the eyes were made to align (surgically), but anomalous projection continued to match up information between the two eyes based on the way they had been positioned for years up until the surgery. In many of these cases, the patient begins to see double after the eyes have been re-positioned. Even worse, these patients may experience visual confusion. Visual confusion is the appearance of two different objects overlapping, as if they come from the same place. The brain now has the same two main options for avoiding visual confusion: suppression and anomalous projection. Since anomalous projection worked successfully before, these patients may learn to re-assign information based on their new eye positions. But without the guidance of vision therapy, many of these patients re-establish their eye turn to the same position that their eyes held before the surgery. Some patients even end up with the eyes switching to turn the opposite way after surgery!
Vision therapy for patients with an eye turn is a rehabilitation process which helps the brain adapt to a change in the relative positions of the eyes. It trains the brain to make use of information coming from two directions, and to marry the pieces of information into a single image. It also trains the brain to be flexible in coordinating the eyes over a range of distances and demands.
Ideally, vision therapy for eye turns should be addressed BEFORE surgery is attempted. Sometimes, successful vision therapy negates the need for strabismus surgery. Other times, vision therapy prepares the brain so that surgery is successful and will hold. If surgery is performed, vision therapy should also be conducted AFTER surgery to help stabilize the visual system and maximize the positive outcome. It takes training to learn to see and appreciate the world in 3-D, especially for patients with a long history of an eye turn. The long term benefits of vision therapy for eye turns include:
-Less energy exerted when reading:
-More energy available for thinking!
-Less loss of place/ skipping lines
-Better sense of spatial organization:
-Improved ability in sports and athletics
-Easier time parking a car
-Better depth perception:
-Greater accuracy in hand-eye coordination
-More enjoyment of the visual world
-Better use of peripheral vision:
-Easier time “seeing the forest while viewing the trees”
For an appreciation of how life can be changed after vision therapy for an eye turn, I strongly recommend reading “Fixing My Gaze,” by Susan Barry. This first-hand account chronicles the life experience of a person who had an eye turn from infancy, had multiple strabismus surgeries, and did not begin vision therapy for her eye turn until the age of 48.
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D Fortenbacher, O.D.,FCOVD
Nathan Bonilla-Warford, OD
Dr. Rochelle Mozlin
Dominick Maino, OD, MEd, FAAO, FCOVD-A
Benjamin C. Winters, O.D.
[...] This post was mentioned on Twitter by Bradley Habermehl, COVD Vision Therapy. COVD Vision Therapy said: Strabismus — Is Surgery Enough? http://ht.ly/426us [...]
Fantastic information. We’re posting this on our Facebook page – http://www.facebook.com/thevisiontherapycenter
54 years ago (age 5), I had my first eye operation for strabismus, and 42 years ago (age 17) I had my second. One year ago (age 58) I began vision therapy. Until then, my world was two-dimensional. After several months of therapy, I saw in 3-D for the first time. I cannot express the excitement, joy and wonder of seeing space between things. Prior to this, things just looked like they were overlapping. I’m still doing vision therapy to further refine my steriopsis. It is a thrilling journey.
Dear Hope,
Thank you for posting! I am so glad you have found new enjoyment in your life through visual experience. Your story is inspirational.
May I ask what your expectations were of your second surgery? Did it include a change in function?
What drove you to begin vision therapy?
Best regards,
Samantha Slotnick
My expectation was cosmetic. I hoped to have “straight” eyes. And, I did. I did go to an orthoptist after surgery, who told me, “I can probably get your eyes to work together, but you might see double for the rest of your life.” I declined the offer.
It wasn’t until I read Oliver Sachs’ piece about Sue Barry in the New Yorker, that I realized I was missing something; that I saw the world very differently than most people. After sitting down and crying about this new concept, that I was really deprived of something wonderful, I decided to explore vision therapy. I give great thanks to Dr. Sachs for “opening my eyes” to the possibilities, to Sue Barry for her extraordinary descriptions of her own development of steriopsis; and to my vision therapist, who is helping me broaden my abilities.
Every word wroten here, should to be translated in many languages. If you agree. I will translate your blog in German. I agree in all issues. great job! Joe
Dear Dr. Samantha,
This is great stuff, and very important. I especially take to heart your comments regarding AP and Suppression.
I posted a link to this blog on the Vision Therapists’ Google Group and have asked them to spread the word.
warmest regards,
Linda Sanet, COVT
Dr. Slotnick,
An excellent post. Operating on strabismus without preparing the patient with therapy is a little like throwing a child in the water without teaching him to swim. Some make it; some don’t.
Well presented! Thanks for the information.
Dear Dr. Slotnick,
This is a great article! Being a Nurse I have frequently seen patients with Strabismus and I feel much more informed. What a logical concept and it is a shame patients are not routinely instructed on this option. It’s not like an Orthopedic Surgeon does a Total Knee replacement and sends a patient home without Rehab Therapy! Eye surgery should be no different! Thank you for adding to my knowledge!
Sincerely
Carrie
My two year old has amblyopia and esostrophic strabismus in his left eye, measuring 40; so quite a big eye turn..do you think it’s possible to realign eyes with vision therapy, especially at such a young age? I have been patching his eyes daily and im told today that he has 20/20 vision if that means anything…I would appreciate your views..
Dear Irene,
Thank you for writing about your son.
I will try to provide some insights that may help you, but I would encourage you to seek out a behavioral or developmental optometrist for specific guidance on helping your son develop binocular vision skills. If you check the “Locate a Doctor” feature through the COVD website (https://covdwp.memberpoint.com/WebPortal/BuyersGuide/ProfessionalSearch.aspx) you will be able to identify someone near you who can help.
Often, patients with esotropia (an eye turn inward) have what is called a “centration point,” a place very near to their eyes where both of the eyes are aiming at the same point in space. This centration point provides an entry for developing binocular (two-eyed) experience and extending it outwards. You can develop this right away by playing “airplane”-type games with his food. For example, when you bring food on a spoon towards the eyes, very close, so that it looks like his eyes are both pointing directly at the spoon, slowly pull the spoon back and observe if he separates his eyes (“diverges”) in order to keep both eyes on the food.
An eyeglass prescription may assist your son in relaxing his eyes and developing a range over which he can extend his two-eyed seeing. Again, I recommend consulting with a behavioral or developmental optometrist to obtain an optimal prescription geared to facilitate development. This is not intended as a “corrective” prescription, but rather a “therapeutic” prescription.
At the age of two, it is not too early to introduce activities and interventions which will help your son to make changes in the way he is using his eyes. Often, with young children, these changes are gradual and subtle, but over a year of therapy I will observe decreases in the total size of the eye turn. While your son may not be quickly and fully remediated, the early experiences in developing binocularity may serve as building blocks towards making progress later, and without the intervention of surgery.
There are distinct advantages to avoiding surgery altogether: The connections between nerves and the muscles they control remain intact. There is some evidence that in the long run, it is easier to control muscles that have not had surgical intervention.
Consider esotropia as a binocular (two-eyed) problem. The way towards resolving a two-eyed problem is through two-eyed experiences. Patching, however, *deprives* the brain of two-eyed experiences, and should not be undertaken for prolonged periods. You can reference the Amblyopia Treatment Studies, which are clinical trials showing that (1) extensive patching is not necessary to gain improvements in amblyopia, and (2) patching is best undertaken in short, 30 minute periods with detailed, interactive activities (like connect-the-dots or working on puzzles or manipulative games).
Amblyopia literally means “lazy eye,” and refers to a reduction in vision potential through an eye. Vision does not fully develop in a “lazy eye” because the eye is not receiving a clear image. This may be due to an eye turn, a high prescription (especially if one eye has a “normal” prescription), or an opacity blocking light through the eye (such as a cataract which is present from birth).
If your son has attained 20/20 vision with each eye, amblyopia is no longer the primary issue, and he is now likely to switch which eye he views with. I would not continue to recommend patching, with the exception of specific, prescribed activities. Patching may help one eye develop its ability to see on its own, but patching for prolonged periods will interfere with binocular experience.
There are ways, through vision therapy, to challenge one eye at a time while both eyes are still seeing. These activities are very successful at teaching the brain how to take information from both eyes at the same time, rather than taking turns between the right and left views of the world.
I hope this provides some perspective on the potential your son has to develop the ability to see with two eyes together. The guidance of a behavioral or developmental optometrist is a critical component of a successful outcome.
Best of luck!
Dr. Samantha Slotnick
Hi, my 4 year old son has had strabismus surgery a year ago. Mostly corrected now but may need fine-tuning surgery.
At a recent check-up with an expert orthoptist at Sydney Hospital, he failed a 3D vision test.
The orthoptist said that he will never be able to see 3D as that develops earlier and once that period is missed it’s impossible to develop later. That depressed me and my wife.
I see blogs where people say they developed 3D vision later after strabismus correction.
Could the orthoptist be wrong? Our next appointment with the opthalmic surgeon isn’t until June 2011
Hello, James,
Sorry for the delayed response.
I would not take your orthoptist at his/her word with the negative prognosis on 3D vision. However, you may need the assistance of someone who takes a different approach to visual processing. I recommend you seek an opinion from a behavioral optometrist. Try the website for the Australian College for Behavioral Optometrists: http://www.acbo.org.au/
I have asked for specific recommendations on doctors from my colleagues. If you would like to provide your email address, I will send you a recommendation directly.
Best of luck!
Dr. Samantha Slotnick
Dear Dr Slotnick
Thank you for your comment and kind wishes. I’m glad there may be some hope for my son developing 3D vision. I will check out the website for the Australian College for Behavioral Optometrists: http://www.acbo.org.au/
My email address is jmoshide@ozemail.com.au
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My daughter (age 13) is facing her 7th (yes, 7th) strabismus surgery in the next couple months. We have switched surgeons prior to the last one, and I do have confidence in our new dr.’s abilities. But I am truely curious about eye therapy. I have to believe that there are options out there other than surgery over and over and over again that will help to prevent this issue. Or things that can be done post or prior to help strengthen the muscles so we can get off this roller coaster – she does not deserve this!!. She was born 4 weeks early with Pulminary Atresia, so we had to get her heart issues under control before addressing the eyes. Her first surgery wasn’t until she was 1 1/2 – which I understand is a little late for the best results. Before we go into this next surgery, I do have alot of questions for our dr., and would appreciate more inforamtion on eye therapy so that I can discuss intelligently with him. Thank you,
Dear Vicki,
Please, PLEASE seek out the opinion of a behavioral optometrist before following through with this 7th surgery. It is not about your surgeon’s abilities. It is about your daughter’s ability to make sense of images from two different eyes into a single, whole picture.
==> No surgeon can do this for her. <==
This visual fusion goes on in the BRAIN, not at the eyes.
This is why, I repeat: NO SURGEON CAN DO THIS FOR HER.
I am glad you are asking questions and looking for help.
If your daughter has re-adapted an eye turn SEVEN times, and if you do not change your course of care now, I would bet money on her re-adapting an eye turn an eighth time.
She is telling you something: She does not know how to put the images together. So she is preferring to pull them apart.
She requires a different approach.
She requires Optometric Vision Therapy for strabismus.
If you would like to provide an email address or your location, I can offer a specific recommendation for a behavioral optometrist near you. Otherwise, try locating a doctor on
http://www.covd.org
OR
http://www.oepf.org.
Best wishes,
Dr. Samantha Slotnick
Thank you all for your comments and suggestions. We are in Norfolk, Virginia, and would be willing to travel to see someone for a consult. I would love a recommendation. We CANNOT keep going on this train.
V.
tv.townsend@verizon.net
Dear Vicki,
In addition to the excellent comments offered by Dr. Slotnick, a few other points to consider. At this juncture your daughter likely has so much scar tissue from prior surgical procedures on her eye muscles that if we were talking about muscles elsewhere in the body anyone doing further surgery without consideration of non-surgical therapeutic options might be guilty of malpractice. For many reasons, eye muscle surgeons ignore all of the points that Dr. Slotnick raises in her original post, and in her caution to you. In addition to the sources she provided from COVD and OEP, here is a brief overview from the American Optometric Association:
(http://www.aoa.org/x4700.xml)
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Prism lenses are special lenses that have a prescription for prism power in them. The prisms alter the light entering the eye and assist in reducing the amount of turning the eye has to do to look at objects. Sometimes the prisms are able to fully compensate for and eliminate the eye turning.
Vision therapy is a structured program of visual activities prescribed to improve eye coordination and eye focusing abilities. Vision therapy trains the eyes and brain to work together more effectively. These eye exercises help remediate deficiencies in eye movement, eye focusing and eye teaming and reinforce the eye-brain connection. Treatment may include office-based as well as home training procedures.
Eye muscle surgery can change the length or position of the muscles around the eye in an attempt to better align the eyes. Eye muscle surgery may be able to physically align the eyes so they appear straight. Often a program of vision therapy may also be needed to develop a functional improvement in eye coordination and to keep the eyes from reverting back to their previous condition of misalignment.
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For more information on how surgeons provide selective information about multiple eye muscle surgery outcomes, see:
http://www.strabismus.org/surgery_crossed_eyes.html
Dear All, Since I last wrote, it was determined that Terry, my son, still had a problem after 2 ops on his right eye. Our surgeon convinced us that a third op on the good left eye was needed to balance out the right eye. We went along with that because there was a suggestion that it might restore binocular vision. The third operation failed and now he has esotropia in the left eye. The surgeon is regarded as the best in Sydney, Australia and he was surprised and suggested Terry needed a 4th operation 9on the left eye). He asked me for permission for a second opinion from his practice partner and his practice partner agreed on a 4th operation. As my wife is Japanese, she wanted opinions from Japan. The first Japanese specialist suggested prism glasses before deciding on a 4th operation. The second Japanese specialist agreed with glasses. When we returned to Sydney with those opinions, the surgeon agreed on a trial of glasses but gave him mild prescription glasses and not prism glasses. We are to return for a review in a few months but the trial is supposed to last for one year. I have yet to take him to a behavioural optometrist but after the review, I will look for one.I appreciate the kind help of Dr Slotnick and apologise for not acting on her advice sooner.
Dear James,
Thank you for sharing your story. I am sure many can learn from the challenges you have been facing with your son.
Please keep us informed after you take your next steps!
Best wishes,
Dr. Samantha Slotnick
Strabismus surgery is seldom as successful as we would hope it to be. Please see. Maino D. The number of placebo controlled, double blind, prospective, and randomized strabismus surgery outcome clinical trials: none!. Optom Vis Dev 2011;42(3):134-136. at http://www.covd.org/Portals/0/OVD/42-3/Editorials/OVD%2042-3%20Journal_Editorial_Maino_web.pdf
Thanks for the article – the more I read about vision therapy the more I am wishing I had known about this a long time ago. We have an appt for my daughter in 2 weeks with a dr. that has been doing vision therapy for about 20 years. But I have a concern – I don’t want to alienate our surgeon in the process of finding out more information about an alternative course of action. I believe that ultimately we may need to have both professionals working together for the best possible outcome for my daughter. I will be setting up an appointment with our surgeon to go over what has been done in the past and what he hopes his suggested upcoming surgery will provide and discuss the fact a that surgery after surgery after surgery doesn’t seem to be effective. Are my concerns legitimate, or am I worrying about something that i don’t need to be? Any suggestions would be appreciated.
My opinion is that you need to act in your best interest. It may be useful to have surgical support in the future, after she has learned how to fuse visual information with her brain FIRST. At that time, I agree, the best option is to have the two doctors co-managing care, communicating with each other. In cases where a surgeon has accepted input from me, it has worked out in the patient’s best interest EVERY TIME.
In many strabismus cases where the patient has never had vision therapy, the surgeon tends to leave the eyes slightly crossed, as this is not cosmetically noticeable, and the patient often learns to suppress the vision from one eye. Surgeons tend to perform this over-correction of a tendency for the eyes to turn outward as a way to try to prevent the eye from drifting again. However, if a patient doesn’t adapt to this posture, the eyes will re-adapt a turn (sometimes turning even farther inward, sometimes turning outward again).
Your daughter is an example of a patient who is not independently “figuring out” how to use her eyes together when they point straight. SO, she has re-adapted the turn SEVEN TIMES.
Once a patient has optometric vision therapy, they learn to start using visual information from a larger area of their retinas. They learn to process information simultaneously between the two eyes. Optometrists may use tools, like prisms, lenses, filters and occlusion to help a patient change how they process visual information. At times, the patient can use their eyes as a team with the help of glasses, but they cannot keep their eyes straight without glasses.
To help reduce the amount of motor work the patient must do to hold their eyes straight, sometimes a surgery is recommended as a part of therapy.
In these cases, by co-managing, the optometrist can inform the surgeon about the muscle skills the patient has developed, and what the patient is capable of doing. When I have been able to co-manage a strabismus patient THROUGH surgery, my patients have done well and been successful cases. Usually, after surgery, a bit more therapy helps the patient stabilize their visual system (similar to having physical therapy after any orthopedic surgery to relearn how to use the body with the surgical changes).
However, I have had three cases in the last three years where a surgeon has performed surgery on vision therapy patients without the input of the managing optometrist, and the patient has been left with double vision and a whole new set of challenges to work through after surgery.
This is because optometric vision therapy helped the patient learn to use both eyes as a team, so they were no longer likely to suppress an eye. As I explained above, the surgeon frequently over-crosses the eyes, because this stabilizes many strabismic patients who have never had surgery or therapy. However, patients who have learned to use their eyes as a team know how to make fine adjustments to keep their eyes coordinated, providing them with single vision while both eyes are working. It is much easier for people to pull their eyes closer together (converge their eyes) if they are left slightly under-crossed after surgery than to learn how to spread the eyes apart (diverge the eyes) if they are left slightly over-crossed after surgery. This is the OPPOSITE of what is usually recommended for strabismus surgery, with patients who have never had surgery or therapy. Hence, co-management is always the best approach. When professionals are working in your best interests, they will not be so ego-driven as to refuse co-management.
As a health care professional involved in a patient’s case, I always appreciate a patient’s phone call to let me know that they are exploring some options and alternatives, and that they appreciate the help and counsel I have offered to date. Keep in mind, “doctor’s orders” are really doctor’s recommendations. Your surgeon should be happy to be available to you as YOU wish and when you ask for support. You are not obliged to more. This person is a medical professional, not a personal friend. You do not to be concerned that they will hold a grudge because you didn’t do exactly as they recommended when they recommended it. There is no reason to think that delaying a plan for surgery will result in them closing the door on you or your daughter.
Good luck, and please come back and keep this blog informed of your daughter’s progress!
Dr. Slotnick
Thanks for the article Dr Maino, after reading it I will need a heck of a lot of convincing to let Terry have a 4th operation.
I have touched base with Rosemary Paynter, a lecturer/behavioural optometrist at the University of New South Wales (my alma mater). I’ve forwarded to her all of Terry’s summaries contained in the surgeon’s referrals and the Japanese opinions. We hope to have an appointment in her clinic in a few weeks. Like Vicki, I hesitate to tell the surgeon but hopefully he will take it well. Once there is an update, I will post it. Thanks again Dr Slotnick (if you are interested in getting a copy of Terry’s summaries I can send them to you via email)