Periorbital botulinum toxin A improves photophobia and sensations of dryness in patients without migraine: Case series of four patients

Abstract

Purpose Individuals receiving botulinum toxin A (BoNT-A) injections in the head and neck for migraine treatment have reported decreases in photophobia and sensations of dryness, independent of ocular surface parameters. We hypothesized that patients without migraine but with similar ocular neuropathic-like symptoms would also experience symptomatic improvement with periocular BoNT-A injections, independent of ocular surface changes. Observations We identified four individuals without a history of migraine but with neuropathic ocular pain (symptoms of dryness, burning, and photophobia that were out of proportion to ocular surface findings and unresponsive to ongoing dry eye (DE) therapies). Individuals underwent 1 session of periocular BoNT-A injections. Validated questionnaires (Visual Light Sensitivity Questionnaire-8, Dry Eye Questionnaire-5) assessed photophobia and DE symptoms pre- and 1-month post-injections. All four reported improvements in frequency and severity of photophobia and eye discomfort following BoNT-A injections. Tear film parameters (phenol red thread test, tear break-up time, corneal staining, and Schirmer test) and eyelid (palpebral fissure height and levator palpebrae superioris function) and eyebrow (position) anatomy were also evaluated before and after injections. Despite a unanimous improvement in symptoms, there were no consistent changes in ocular surface parameters with BoNT-A injections across individuals. Conclusions Periocular BoNT-A shows promise in reducing photophobia and sensations of dryness in individuals with neuropathic-like DE symptoms without a history of migraine, independent of tear film, eyelid, or eyebrow parameters.

Exploring the Link Between Dry Eye and Migraine: From Eye to Brain

“…In 4 individuals with dry eye symptoms without migraine, a modified botulinum toxin A protocol (35 units in 7 sites) improved photophobia and dry eye symptoms 1 month post vs pre injection. 107 Together, these data suggest that botulinum toxin A may improve photophobia and dry eye symptoms in individuals with and without migraine.…”

Differential Effects of Treatment Strategies in Individuals With Chronic Ocular Surface Pain With a Neuropathic Component

“…Botulinum toxin injection is another adjuvant therapy often applied to chronic ocular pain, being most frequently utilized in patients with migraine, with studies generally reporting a mild to moderate improvement in ocular symptoms after treatment ( Johnson, 2007 ; Diel et al, 2018 ; Venkateswaran et al, 2020a ). For example, an American study of 76 patients with chronic migraine who received BoNT-A toxin injections (100–150 U) reported a significant decrease in interictal photophobia scores (3.37 ± 2.54 from 4.89 ± 2.97, p < 0.001, range 0–10) after treatment (mean FU of 30.5 ± 7.65 days, range 19–56 days) ( Diel et al, 2019 ).…”

“…The migraine BoNT-A has been modified and used in individuals with neuropathic ocular pain but without a history of migraine. Four individuals treated with one session of BoNT-A (35 U given across seven forehead sites) reported a decrease in photophobia severity (3.25 ± 0.4 from 4.8 ± 0.4, range 0–5) and ocular discomfort (2.25 ± 1.0 from 4.5 ± 0.6, range 0–5) at 1 month follow-up ( Venkateswaran et al, 2020b ). In our current study, eight of 10 migraine-like pain patients who received botulinum toxin injections reported a subjective improvement in ocular pain (4 mild, four moderate).…”

Novel Treatments for Chronic Ocular Surface Pain

“…Interestingly, the improved symptoms occurred without notable changes in ocular surface parameters, indicating that pain was not being driven by tear and anatomic abnormalities in this population. 71 Other agents that block CGRP such as erenumab, eptinezumab, galcanezumab, and fremanezumab 72 may also have a beneficial effect on NOP, but this approach remains to be tested.…”