Natural History of MTBI-related Convergence Insufficiency & Effectiveness of Vision Therapy for MTBI-related CI

Inclusion Criteria: * • Age 18 to 35 years inclusive * Medical diagnosis of mTBI or concussion \> 1 month ago and no longer than 6 months ago * Convergence Insufficiency Symptom (CISS score) ≥ 21 * Best-corrected VA of 20/25 or better in both eyes at distance \& near * Willingness to wear refractive correction, if indicated * Random dot stereopsis of 500 arcsec or better (Randot Stereo Test) * Receded NPC of ≥6 cm * Insufficient PFV (\< 15∆ or PFV blur point less than twice the near exophoria magnitude) * Wearing refractive correction for cycloplegic refractive errors of: * ≥ +1.25 D SE hyperopia or ≥ -1.00 D SE myopia in either eye * ≥ 1.25 D astigmatism in either eye, ≥ 1.00 D SE anisometropia * Astigmatism axis within ±10 degrees if magnitude is ≤1.00 D and within ±5 degrees if \>1.00 D Exclusion Criteria: * • No previous treatment for CI * No previous diagnosis of CI from an ophthalmologist or optometrist * No medications known to affect accommodation or vergence * Investigator \& patient willing to forgo all other CI treatment other than that assigned by randomization