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

Abstract

Background: Dysfunction at the ocular system via nociceptive or neuropathic mechanisms can lead to chronic ocular pain. While many studies have reported on responses to treatment for nociceptive pain, fewer have focused on neuropathic ocular pain. This retrospective study assessed clinical responses to pain treatment modalities in individuals with neuropathic component ocular surface pain.Methods: 101 individuals seen at the University of Miami Oculofacial Pain Clinic from January 2015 to August 2021 with ≥3 months of clinically diagnosed neuropathic pain were included. Patients were subcategorized (postsurgical, post-traumatic, migraine-like, and laterality) and self-reported treatment outcomes were assessed (no change, mild, moderate, or marked improvement). One-way ANOVA (analysis of variance) was used to examine relationships between follow up time and number of treatments attempted with pain improvement, and multivariable logistic regression was used to assess which modalities led to pain improvement.Results: The mean age was 55 years, and most patients were female (64.4%) and non-Hispanic (68.3%). Migraine-like pain (40.6%) was most common, followed by postsurgical (26.7%), post-traumatic (16.8%) and unilateral pain (15.8%). The most common oral therapies were α2δ ligands (48.5%), the m common topical therapies were autologous serum tears (20.8%) and topical corticosteroids (19.8%), and the most common adjuvant was periocular nerve block (24.8%). Oral therapies reduced pain in post-traumatic (81.2%), migraine-like (73%), and unilateral (72.7%) patients, but only in a minority of postsurgical (38.5%) patients. Similarly, topicals improved pain in post-traumatic (66.7%), migraine-like (78.6%), and unilateral (70%) compared to postsurgical (43.7%) patients. Non-oral/topical adjuvants reduced pain in postsurgical (54.5%), post-traumatic (71.4%), and migraine-like patients (73.3%) only. Multivariable analyses indicated migraine-like pain improved with concomitant oral α2δ ligands and adjuvant therapies, while postsurgical pain improved with topical anti-inflammatories. Those with no improvement in pain had a shorter mean follow-up (266.25 ± 262.56 days) than those with mild (396.65 ± 283.44), moderate (652 ± 413.92), or marked improvement (837.93 ± 709.35) (p < 0.005). Identical patterns were noted for number of attempted medications.Conclusion: Patients with migraine-like pain frequently experienced pain improvement, while postsurgical patients had the lowest response rates. Patients with a longer follow-up and who tried more therapies experienced more significant relief, suggesting multiple trials were necessary for pain reduction.

Novel Treatments for Chronic Ocular Surface Pain

“…Transcutaneous electrical nerve stimulation (TENS) and botulinum toxin A (Botox) are 2 such adjuvant therapies often used in migraine that have been applied to NOP. 61 In addition, periocular nerve blocks, often used to treat individuals with neuralgia, are another adjuvant treatment option applied to individuals with NOP.…”

Ocular surface itch and pain: key differences and similarities between the two sensations

“…Gabapentin was started at 300 mg oral (daily) and titrated up to 600–900 mg (thrice a day), while pregabalin was started at 75 mg oral (daily) and titrated up to 150 mg (twice a day). Two individuals experienced complete relief from pain, three had marked relief, one experienced mild relief, and two showed no improvement [74]. In the study, patients with marked relief also took oral serotonin norepinephrine reuptake inhibitors (SNRIs), suggesting a multifaceted approach could benefit those with chronic ocular surface pain.…”

“…In the study, patients with marked relief also took oral serotonin norepinephrine reuptake inhibitors (SNRIs), suggesting a multifaceted approach could benefit those with chronic ocular surface pain. [74,75]. Tricyclic antidepressants (TCA) have also been used with success.…”

Acupuncture for neuropathic pain in patients with dry eye disease: protocol for a systematic review and meta-analysis

“…Reports underscored the e cacy of oral antiepileptic drug gabapentin in effectively addressing NP [33] . Furthermore, antidepressants such as duloxetine and venlafaxine [34] , tricyclic antidepressants (TCAs), and opioid antagonists like naltrexone are also viable options for mitigating NP [24,[35][36][37] . Atypical opioid drugs (tramadol) and anticonvulsants (carbamazepine, oxcarbazepine, topiramate, lamotrigine) [38,39] , have been recommended for the management of NP.…”