Strabismus: Non-Surgical Treatment at Perspective Optometry

Strabismus, commonly known as an "eye turn" or "crossed eyes," is a condition that affects millions of people worldwide. It’s far more than just a cosmetic concern; it represents a fundamental breakdown in the visual system, forcing the eyes to aim in different directions. This condition interferes with the brain’s ability to create a single, clear, three-dimensional image of the world.

While strabismus surgery has historically been the primary treatment, modern optometry and recent clinical research emphasize a crucial first step: non-surgical management.

At Perspective Optometry, we specialize in providing evidence-based, non-surgical solutions—ranging from specialized lenses to active visual training—designed to restore comfortable, functional binocular vision. As recent research confirms, "In recent years, with the continuous advancement of medical technology, an increasing number of non-surgical treatments have been applied in the management of pediatric strabismus, yielding certain positive results." (Huang et al., 2025).

We believe true correction means not just straight eyes, but eyes that work efficiently and comfortably together, often without the need for surgical intervention.

What Exactly is Strabismus? Defining the Eye Turn

Strabismus occurs when the eyes are misaligned, meaning that when one eye looks straight ahead at a target, the other eye turns either inward, outward, upward, or downward. This prevents both eyes from simultaneously focusing on the same point in space.

The condition is primarily rooted in the brain, which fails to coordinate the six muscles surrounding each eye to work in perfect tandem. This neurological breakdown prevents the development of fusion—the brain's ability to merge the two images from the eyes into one single, coherent picture.

Common Eye Turn Classifications:

• Esotropia: The eye turns inward (cross-eyed).

• Exotropia: The eye turns outward (walleye).

• Intermittent Strabismus: The eye turn appears only sometimes, often due to fatigue or stress.

The Functional Crisis: Why Strabismus Affects More Than Looks

The functional deficit caused by strabismus is significant. To cope with the confusion of conflicting images (diplopia, or double vision), the brain often suppresses the visual input from the turned eye. This reliance on one eye results in two major problems:

1. Amblyopia (Lazy Eye): The suppressed eye fails to develop normal visual acuity.

2. Loss of Stereopsis (3D Vision): The brain loses the ability to perceive true depth, impacting activities like sports, driving, and fine motor skills.

Non-Surgical Treatments: Fixing the Function

Non-surgical treatments are the first line of defense for strabismus, focusing on stabilizing the visual system, promoting eye alignment, and teaching the brain to fuse images before considering muscle surgery.

1. Therapeutic Lenses (Glasses and Bifocals)

Corrective lenses are often the simplest and most crucial step, particularly for Accommodative Esotropia, where the eye turn is caused entirely by focusing effort.

• Refractive Correction: Simply prescribing the full, accurate corrective lenses (for farsightedness, or hyperopia) can often completely eliminate the inward turn. This alleviates the need for the brain to over-focus, which typically triggers the misalignment.

• Bifocals: In some cases, a bifocal lens is needed to reduce the focusing effort required specifically for near tasks, preventing the eye from turning inward when reading or doing close work.

2. Occlusion Therapy (Patching)

Occlusion, or patching, is often used to treat or prevent amblyopia that results from strabismus.

• Function: Patching the straight eye forces the brain to use the turned, weaker, or amblyopic eye. This stimulates the visual pathways and encourages improved visual acuity in the suppressed eye.

• Goal: The primary goal is to equalize vision between the eyes so that the eyes can eventually learn to work together.

3. Prism Correction

Prisms are specialized lenses that bend light before it reaches the eye. They are a passive treatment used to immediately alleviate symptoms.

• Function: The prism shifts the image seen by the misaligned eye so that it lands on the retina in the spot corresponding to the image from the straight eye.

• Goal: This immediate shift helps eliminate double vision (diplopia) or reduce visual confusion, providing immediate relief and comfort, especially for small-angle deviations or residual turns after surgery.

4. Optometric Vision Therapy (VT)

Vision Therapy (VT), Visual Training, and Neuroplasticity Training all refer to the same structured program of personalized exercises aimed at fixing the fundamental eye-brain connection deficiency. Unlike the passive treatments above, VT is an active, rehabilitative solution.

• Function: VT trains the brain to gain accurate, voluntary control over the eye muscles, teaching the eyes to overcome suppression and actively achieve and sustain fusion.

• Goal: To achieve functional cure—stable, comfortable, single binocular vision, eliminating the need for the eye to turn.

Vision Therapy Process: Retraining the Brain to See in 3D

Vision Therapy systematically teaches the brain to accept and use the input from both eyes simultaneously, which is the precursor to achieving fusion.

The process follows three progressive phases:

Phase 1: Establish Simultaneous Perception (Sensory)

The first critical step is breaking suppression. We use specialized tools (like red/green filters) to make the brain consciously aware of the image coming from the turned eye, which often leads to temporary, controlled double vision (diplopia)—a necessary step to confirm the brain is no longer ignoring the eye.

Phase 2: Achieve and Sustain Fusion (Motor)

Once the brain is aware of both images, the focus shifts to building the vergence motor skills needed to pull those two separate images together into one fused image. Tools include prism flippers, vectograms, and computer orthoptics used in repetitive, challenging exercises.

Phase 3: Develop Stereopsis and Automation (Cognitive)

The final phase aims for the highest level of visual function: stereopsis (true 3D vision) and the automation of the new visual skills for use in real-world scenarios, making the new binocular control effortless and automatic.

Why Non-Surgical Options are Often Preferred

While strabismus surgery is sometimes unavoidable, many parents and adult patients choose to pursue non-surgical rehabilitation first.

The reasons for choosing a rehabilitative approach over immediate surgery often center on avoiding the inherent risks, recurrence rates, and limitations of an invasive procedure:

High Risk of Recurrence and Repeat Surgery

Surgery's primary limitation is that it does not correct the brain's neurological programming. This can lead to the misalignment recurring over time.

• Repeat Surgeries are Common: Recurrence (the eye turn returning) is a known issue. Depending on the type of strabismus and follow-up duration, reoperation rates are frequently cited in ophthalmic literature, ranging from 15% to 40%. This high rate means the patient may face the expense, downtime, and risks of surgery multiple times.

• Cosmetic vs. Functional Success: The straight look achieved immediately after surgery often fails functionally. While surgery achieves high cosmetic alignment rates, optometric Vision Therapy achieves significantly higher functional success rates (often quoted between 75% to 87%) in restoring binocular vision, fusion, and stereopsis, compared to surgery alone (which typically achieves 15-22% functional success). This is the core difference: VT focuses on how well you see versus how you look (Mitchell & Rouse, 2018).

Risks of General Anesthesia

Strabismus surgery, particularly for pediatric patients, requires general anesthesia (GA), which carries serious and unavoidable risks.

• Neurodevelopmental Risks: Ongoing research highlights concerns about the potential for GA, particularly long or repeated exposures in early childhood, to be associated with learning disabilities or other neurodevelopmental risks.

• Extremely Rare Mortality Risk: Although extremely rare due to modern safety standards, the risk of death directly related to general anesthesia in elective strabismus procedures is an unavoidable, non-zero risk. Older literature estimated this mortality risk to be around 1 in 20,000 to 50,000 cases (Von Noorden). For a voluntary procedure, this risk is a significant factor in parental decision-making.

Intra-operative and Post-operative Complications

Beyond anesthesia, the procedure itself carries risks:

• Complications: These include infection, scarring, overcorrection (eyes turn the opposite direction), under-correction, and in extremely rare cases, vision loss or complications related to muscle attachment.

These risks and the high rate of surgical recurrence emphasize the value of exploring safe, non-invasive rehabilitation first, a preference validated by clinical reviews advocating for non-surgical treatments in children (Huang et al., 2025).

Research and Evidence Supporting Visual Training

Recent research strongly confirms the efficacy of visual training in achieving functional success, making it an essential part of modern strabismus management.

Functional Success vs. Cosmetic Alignment: The Mitchell & Rouse Review

We rely on comprehensive clinical reviews to guide our approach. A critical review by S. J. Mitchell and M. W. Rouse (2018), titled "Optometric Vision Therapy for Strabismus: A Review of Clinical Outcome Research," and published in Vision Development & Rehabilitation, explored the evidence supporting vision therapy as a non-invasive treatment option for eye misalignment. Their analysis summarized several key findings that define the core difference between surgical and non-surgical goals:

• Focus on Functional Outcomes: The review emphasized that the goal of Vision Therapy is to achieve both functional binocular vision (making the eyes work together seamlessly) and cosmetic alignment, directly addressing the underlying brain-eye coordination problem.

• Contrasted with Surgery: The review discussed how VT differs from strabismus surgery. It noted that surgery often focuses primarily on cosmetic straightening, while therapy aims to correct the root cause. The review contrasted the outcomes, citing research indicating that surgery has lower success rates for restoring binocular function (typically 15-22% functional success) compared to the high functional success rates achieved with VT.

• Success Rates and Age: In reviewing existing research, the article referenced studies suggesting high success rates for vision therapy (often quoted between 75% to 87%) when conducted under optimal clinical conditions. The review also touched on research indicating that while younger patients may respond more quickly, adults can still achieve success, noting that adult motivation is a key factor.

• Targeting Strabismus Types: The review discussed evidence showing that intermittent and periodic eye turns are often highly responsive to vision therapy. Furthermore, the review clarified the distinction that while strabismus (eye turn) and amblyopia (lazy eye) are separate conditions, they frequently occur together, and both can be successfully treated with Vision Therapy.

  • Citation: Mitchell, S. J., and Rouse, M. W. (2018). Optometric Vision Therapy for Strabismus: A Review of Clinical Outcome Research. Vision Development & Rehabilitation, 4(2), 75-87.

New Research (Post-2015): High-Level Evidence for Intermittent Exotropia (IXT)

Visual Training as a Primary Treatment for IXT

A landmark randomized controlled trial (RCT) published in Ophthalmic and Physiological Optics (2023) compared office-based vergence and anti-suppression therapy (OBVAT) to observation alone in children with small-to-moderate angle IXT.

• Key Finding: The OBVAT group had a significantly better distance eye control score and were three times more likely to show meaningful improvement in their control of the eye turn compared to the observation group.

• Conclusion on Effectiveness: The researchers concluded that this RCT provided the "first data from a randomised clinical trial demonstrating the effectiveness of OBVAT for improving the control of IXT," thereby establishing it as a viable, non-surgical option that should be considered.
  
  

• Citation: Office-based vergence and anti-suppression therapy for the treatment of small-to-moderate angle intermittent exotropia: A randomised clinical trial. Ophthalmic Physiol Opt. (2023).

VT for Post-Surgical Control and Stability

• Key Finding: A study examining the effect of physiotherapy exercises (which include Vision Therapy components) post-strabismus surgery for intermittent exotropia found that the group receiving the exercises showed a significant improvement in eye control for both near and far targets compared to the control group.

• Citation: Physical therapy exercises for improving intermittent exotropia control post-strabismus surgery: A randomized controlled study. Hong Kong Physiotherapy Journal (2024).

Foundational Evidence

• Endorsement of Non-Surgical First Line Treatment: A very recent review of non-surgical advances in strabismus treatment for children confirms that Vision Therapy, corrective lenses, and prisms are essential components used to improve visual acuity and preserve or restore binocular function.

  • Citation: Non-surgical treatment of strabismus in children: a review of recent advances. Front Med (Lausanne). (2025). PMID: 40655112.

• Intermittent Strabismus: For many cases of intermittent exotropia (the eye turns out sometimes), Vision Therapy is often the first line of treatment. Clinical studies consistently show high success rates in treating IXT, often defined as achieving functional success in the majority of treated cases. Success is measured by the patient's ability to maintain eye alignment and comfortable fusion in daily life, significantly reducing the frequency and duration of the eye turn. Source: Office-based vergence and anti-suppression therapy for the treatment of small-to-moderate angle intermittent exotropia: A randomised clinical trial. (Ophthalmic Physiol Opt., 2023).

• The Role of VT Post-Surgery: For patients who have undergone strabismus surgery, Vision Therapy is frequently recommended as an essential adjunctive treatment. Surgery corrects the large angle of the turn, but the brain's habit of suppressing or its inability to achieve fusion often remains. VT is required to teach the eyes to use their new alignment. Studies demonstrate that patients who combine surgery with pre- and post-operative Vision Therapy often achieve superior functional outcomes (better depth perception and fusion) compared to surgery alone.

• Treating Residual Strabismus and CI: Vision Therapy is highly successful in treating residual strabismus (small turns remaining after surgery) and functionally related alignment disorders like Convergence Insufficiency, which often mimics a mild intermittent outward turn. The CITT (Convergence Insufficiency Treatment Trial) established that office-based VT is the gold standard for improving eye teaming and focusing, skills critical for stable binocular vision, even in the presence of strabismus.

Perspective Optometry’s Specialized Approach

Treating strabismus requires deep expertise in binocular and developmental vision. Our approach begins with a Strabismus-Focused Functional Evaluation to precisely measure the angle, the extent of suppression, and the stamina of the eye-teaming system.

We then develop a Customized and Collaborative Care plan using the most appropriate non-surgical tools—from therapeutic prisms and bifocals to our active Vision Therapy program. We are committed to helping you or your child achieve functional binocular vision safely and effectively.

Don't settle for eyes that just look straight. Achieve eyes that work together. Contact Perspective Optometry today to schedule a comprehensive strabismus evaluation and start your journey toward comfortable, functional binocular vision.