Intermittent Strabismus and Eye Muscle Surgery
I just had the pleasure of meeting Joey – an adorable three year old – and his parents. They were referred to my office by an acquaintance after an upsetting consultation with a local ophthalmologist. Around age two his mom noticed little Joey’s eyes crossing improperly from time to time. After a while it seemed to be happening more frequently, but not all the time. Worried, as any first-time parents should be, they sought the advice of someone they thought was an expert.
The ophthalmologist they saw told them Joey needed eye muscle surgery immediately or he risked going blind in one eye. I’m not sure which eye he meant since both eyes had equal clarity of sight and the intermittent eye turn alternated from one eye to the other. When Joey’s dad asked the doctor which muscle or muscles were at fault. The surgeon replied that there was nothing wrong with Joey’s eye muscles but surgery was the way to fix it. I have heard this exact line from almost a dozen parents at this point. He also made it clear that time was of the essence.
Joey’s parents were convinced - before even meeting me - that they would rather try vision therapy if there was any way to avoid surgery. We all decided (well, maybe not Joey) that vision therapy and therapeutic lenses would be the best way to go at this time. Vision therapy is non-invasive and cannot cause permanent damage to the eye muscles and vision therapy has a greater probability of long-term success because it improves eye teaming. Surgery, almost by definition damages the muscles that are operated on and surgery does not necessarily improve eye teaming.
The latest research leaves no doubt that eye muscle surgery should only be used as a last resort, not as a primary approach, in most cases. It is now abundantly clear that eye muscle surgery has some serious drawbacks, thanks to a better understanding of the structure of our eye muscles on the microscopic level. Research also shows that vision therapy typically provides a deeper level of improvement and because of this has a greater likelihood of keeping the eyes straighter longer. Here is why: Eye muscle surgery is a mechanical fix (one which I have just pointed out has very serious flaws). The brain does not always manage to use the modified muscles in a way that provides good eye teaming, which should be the primary goal of any intervention for strabismus. Eye muscle surgery does not typically take function and development into account, only cosmetic appearance.
The primary purpose of vision therapy in cases of strabismus is to help the brain figure out how to get the eyes to work as a coordinated team. The best way to keep the eyes straight is to keep them working together. This is a brain thing, not an eye muscle thing in the vast majority of strabismus cases. Even when eye muscle surgery is needed, and it sometimes is, vision therapy should be an essential part of the treatment to ensure that the brain makes the best use of the two eyes after surgery. Many eye muscle surgeries only keep the eyes looking straight (not necessarily working together) for a few years at best. Vision therapy is likely to last a lifetime in most cases, especially when surgery can be avoided. Eye muscle surgery usually complicates the vision therapy process since the eye muscles are inevitably damaged by the surgery.
Also This Happened
Two days prior to meeting Joey I had my monthly two-person study group (better known as breakfast at a local diner) with one of my mentors who happens to be one of the most accomplished behavioral optometrists I know. He told me a story of a 2½ year old little girl whose mother noticed that on very rare occasions her daughter’s left eye would drift outward.
The ophthalmologist recommended immediate surgery. He warned the parents that if the surgery didn’t take place very soon the child would lose vision in the left eye. His plan was to operate on the left eye to get the eye to stop turning out, but it would probably end up turning in a little he warned. Then he planned to operate on the right eye to line it up with the left. This new arrangement would then give him the important information he would need to operate on both in order to get them into final, optimal alignment. This is exactly how the child’s mother described her consultation to my colleague.
My colleague told me that this surgeon was someone he has referred patients to and that he has done good work. Unfortunately the mindset behind eye muscle surgery is over 100 years old and is desperately outdated, especially now that important new research has come to light. Vision therapy is in most cases a much safer alternative, with greater likelihood of optimal outcome for not just improved appearance, but improved quality of life.
You can read much more on this topic in A Parent Guide to Strabismus, Eye Muscle Surgery and Vision Therapy.