Understanding and Treating Traumatic Brain Injury (TBI) Associated Photophobia With Botulinum Toxin Type A (BoNT-A)

Inclusion Criteria:

• Recruit and enroll male and female subjects, civilians and veterans (1:1 mixanticipated, i.e., n = 25 from each group) of all races and ethnicities.

• ≥18 years of age who are able to consent.

• Report chronic photophobia (Numerical Rating Scale ≥4 on a 0-10 scale, photophobiapresent ≥6 months) with a remote history of TBI (>1 year).

• Inclusion into the study with regard to TBI status will be based on the Departmentof Defense Standard Surveillance Case Definition for TBI Adapted for Armed ForcesHealth Surveillance Division (AFHSB) Use. This can include one hospitalization oroutpatient medical encounter with documented International Classification ofDiseases (ICD9/ICD10) codes as identified within the Surveillance Case Definition.

• Subjects must also have been on a stable medication regimen for the past 3 monthsand must be naïve to BoNT-A treatment for orofacial conditions.

• English as primary language (by self-report).

Exclusion Criteria:

• Individuals with ocular diseases that may confound photophobia, such as glaucoma,corneal and conjunctival scarring, corneal edema, uveitis, iris transilluminationdefects, retinal degeneration, etc.

• Patients who are participating in another study with an investigational drug withinone month prior to screening.

• Pregnant individuals. Pregnant subjects will not be scanned in the functionalMagnetic Resonance Imaging (fMRI). Although there are no known risks associated withMRI during pregnancy, according to facility policy, University of Miami will notscan someone that is pregnant. Therefore, all women of childbearing potential (menstruating or >12 years old) must complete a for stating that are not pregnantwithin 24 hours of each MRI scan.

• Individuals with contraindications to fMRI scanning (e.g. metal implants, pacemaker)will not be offered inclusion.