Amblyopia is the medical term for lazy eye. Typically, the first line of treatment for patients with amblyopia is prescription eyeglasses or contact lenses. Treatment of amblyopia can also include vision therapy, eye patching, eye drops, refractive surgery, or a combination of those options.
The medical eye patch is the oldest and most common treatment for amblyopia. The theory is that covering, or occluding, the strong eye with an eye patch forces the brain to use the weak eye. Having the brain depend on the weak eye encourages the development of better vision.
Kids often dread wearing it, and parents can have trouble forcing and monitoring their children to keep the patch on; however, it has improved the vision of millions of patients with lazy eye for the last thousand years.
For many years, the assumption was that amblyopic patients are anatomically monocular and lacked any functional binocularity. However, recent findings have provided strong evidence for intact binocular processes in adult amblyopes that may have appeared to have been lost but were, in reality, suppressed. (See Hess et al 2014)
Research has shown that applying monocular treatment methods (such as patching) does not reduce suppression, does not strengthen fusion, and does not help re-establish binocularity in amblyopic patients. In fact, stronger suppression may be associated with poorer response to patching therapy in children. Additionally, studies have shown that despite improvements in acuity in the amblyopic eye following patching treatment, there is a significant chance of regression and binocular outcomes remain poor. (See Hess et al 2015)
It is a well known fact (and reported in scientific studies on the subject) that eye patching and eye drop penalization methods of treatment come with significant complications especially with compliance. Vision therapy is a non-invasive option that provides a safe alternative to surgery or use of pharmaceutical agents. Vision therapy may include the use of virtual reality technology in treatment of lazy eye.
Optometric Vision Therapy, commonly referred to as VT, is a doctor-supervised program designed to improve the function of the visual system. Optometric Vision Therapy is conducted under the supervision of an optometrist, supported by ongoing, evidence-based scientific research, beneficial to people of all ages, non-invasive and in some cases can be a safe alternative to surgery, typically supplemented by the use of lenses, prisms, filters, and 3-D activities, among other things, and is individualized to the unique needs of the patient.
For hundreds of years, the primary treatment for amblyopia has consisted of patching or penalizing the fellow preferred eye, thus “forcing” the brain to use the weaker amblyopic eye. Today, the scientific community (optometrists, ophthalmologists, vision scientists, neuroscientists, et al) is dedicating research to more effective (and less invasive) treatment options based on the concepts of perceptual learning, vision therapy, and dichoptic viewing while utilizing new technology such as virtual reality. These treatment options are proving successful in patients of all ages whereas previously patching and penalization treatments were only used in children.
In vision therapy, patients learn how to use the two eyes together, which helps prevent lazy eye from reoccurring. Vivid Vision is used successfully in the treatment of lazy eye. Vision therapy can focus on increasing accommodation, improving accuracy of oculomotor skills, increasing vergence ranges, improvement of spatial perception, and breaking suppression and eccentric fixation. The treatment goal is for the patient to effortlessly function with sound visual skills at a high level of binocularity. This high level of binocularity helps improve vision and will prevent the regression of visual acuity after amblyopia treatment has stopped.
You can read more about optometric vision therapy here.
It was long thought that treating amblyopia, the medical term for lazy-eye, after the "critical age" of 8-12 years old was not possible. Unfortunately, many optometrists and ophthalmologists still believe, refer to, and share this outdated view. Research, clinical trials, and well-documented patient cases, now show that amblyopia can be treated well into adult hood. Many adults seek vision therapy to aid in their overall binocular function.
We now know that there is not a “critical period” in which amblyopia must be treated. The “recovery period” for these conditions continues through life—albeit easier to treat if diagnosed and treated earlier. It is now known and supported widely by research from vision science, optometry, ophthalmology, and neuroscience, that patients of any age can successfully be treated for amblyopia (including strabismic amblyopia). Again, despite these advancements, it is still best if these conditions are diagnosed and treated early on. You can read more about lazy eye in adults here.
Recent research (Ziak et al) has shown visual acuity as well as stereo acuity can improve at statistically-significant levels in amblyopic patients outside of the “critical period” using virtual reality vision therapy technology. Another recent study (Ho et al, 2019) also showed improved visual acuity and stereo acuity in amblyopic and strabismic patients aged 3-69 using virtual reality vision therapy technology who were previously unsuccessful in traditional patching or occlusion therapy.
Levi, DM. Prentice Award Lecture 2011: Removing the Brakes on Plasticity in the Amblyopic Brain Optom Vis Sci. 2012 Jun; 89(6): 827–838
Levi DM, Knill DC, Bavelier D. 2015 Stereopsis and Amblyopia: a mini-review. Vision Res. 114 17–30.
Hess RF, Thompson B & Baker DH. Binocular vision in amblyopia: structure, suppression and plasticity. Ophthalmic Physiol Opt 2014; 34: 146–162.
Hess RF, Thompson B. 2015 Amblyopia and the binocular approach to its therapy. Vision Res. 114 4–16.
Ho et al. (2019) Binocular treatment for amblyopia in adults and children with low-pass filtering when occlusion therapy fails. ARVO 2019 Poster Session.
Žiak P, et al. (2017). Amblyopia treatment of adults with dichoptic training using the virtual reality oculus rift head mounted display: preliminary results.