Case Overview
A 44-year-old female patient, recently involved in a minor motor vehicle accident, presents with post-incident complaints of dizziness and discomfort while reading or using her phone. She also reports experiencing blurry distance vision for 10–15 minutes after near work, likening the sensation to a camera struggling to refocus.

Prior to the concussion, the patient’s progressive lenses functioned effectively. However, post-accident, they no longer provide the same clarity. Despite achieving 20/15 visual acuity at distance, her near vision is reduced to 20/25 in both eyes.

Given that a year has passed since her last eye examination, refractive changes due to aging might be considered. However, the stability of her distance vision prior to the concussion points to mild traumatic brain injury (mTBI) as a potential underlying cause of her current symptoms.
 

Could a Brain Injury Alter Refractive Error?
Research suggests that mTBI can induce refractive changes, with increased myopia being a notable outcome (1). More commonly, mTBI leads to post-traumatic vision syndrome, characterized by symptoms such as:
•    Blurred vision due to pseudomyopia,
•    Accommodative spasms or insufficiency,
•    Dry eyes.
In severe cases, indirect traumatic optic neuropathy may occur, underscoring the importance of a thorough structural eye exam and potential referral to an ophthalmologist.
 

Understanding Presbyopia and Accommodative Dysfunction After TBI
Presbyopia results from the natural aging process, where the crystalline lens hardens, diminishing its accommodative ability. While some theories suggest ciliary muscle weakening, evidence shows the muscle generally retains its function (3). Patients with presbyopia typically need progressive, symmetric near-add adjustments over time.
Accommodative dysfunction post-TBI arises from neural damage to the accommodation system, involving:

• Cortical and subcortical areas,
• The superior colliculus,
• The Edinger-Westphal nucleus,
• Cranial nerve III.

Unlike presbyopia, post-TBI dysfunction can cause asymmetric symptoms, such as accommodative spasm in one eye and insufficiency in the other. This asymmetry, often observed in clinical practice, reflects potential localized brain damage.
 

Diagnosing Post-Traumatic Accommodative Dysfunction
To differentiate between presbyopia and post-TBI accommodative dysfunction:
1.    Near Point of Accommodation (NPA) Testing: Use the push-up method and repeat multiple times.

• Presbyopia: Consistent blur at the expected near point, with no additional symptoms.
• Post-TBI Dysfunction: Variable results accompanied by dizziness, nausea, or headaches.

2.   Clinical Indicators:

• Symptoms inconsistent with age-related presbyopia,
• Onset of accommodative dysfunction following TBI.

Treatment Recommendations
Primary Treatment:

• Neuro-optometric vision rehabilitation (conducted by certified professionals such as FNORA) is the gold standard, even for adults.

Supportive Measures:

• Prescribe single-vision lenses for immediate relief if necessary.
• Avoid over-reliance on progressive lenses in cases of post-TBI accommodative issues.
   

References

1. Fortenbaugh FC, Gustafson JA, Fonda JR, et al. Blast mild traumatic brain injury is associated with increased myopia and chronic convergence insufficiency. Vision Res. 2021;186:1-12.
2. Merezhinskaya N, Mallia RK, Park D, et al. Visual deficits and dysfunctions associated with traumatic brain injury: a systematic review and meta-analysis. Optom Vis Sci. 2019;96(8):542-555.
3. Tabernero J, Chirre E, Hervella L, et al. The accommodative ciliary muscle function is preserved in older humans. Sci Rep. 2016;6:25551.
4. Green W, Ciuffreda KJ, Thiagarajan P, et al. Accommodation in mild traumatic brain injury. J Rehabil Res Dev. 2010;47(3):183-199.
5. Theis J, Starzynski S, Mohan S, et al. Presence of accommodative dysfunction postconcussion in an adult population. J Head Trauma Rehabil. 2022;37(6):e535.