Abstract
Purpose :
Though dry eye syndrome (DES) has traditionally been classified as problems with tear underproduction or evaporation, a number of patients complaining of DES symptoms lack such exam findings. More recently, damage or dysfunction of the corneal somatosensory pathway has been postulated to play a role in the patients’ symptoms and the mechanism has been identified as corneal neuropathic pain (CNP). With traditional DES treatment being frequently ineffective in controlling symptoms, we assess the response to serum tears as a treatment for CNP.
Methods :
Retrospective chart review was conducted from 2014-2017. Consecutive patients referred for significant DES symptoms, with no to mild ocular surface staining, Schirmer ≥ 5mm, and no or partial response to proparacaine instillation were included. Patients were asked to grade their ocular pain on a scale from 0-10 at every visit. Successful response to treatment was defined as any patient-reported improvement in pain score. Difference in pain scores was analyzed by t-test with a significance level of 0.05.
Results :
Thirty patient-charts were reviewed. Of these, 20 were Caucasian, 10 African American, 23 were female, and average age was 54.6 (± 17.78, 21-87). Chronic pain syndromes were documented in 13 and autoimmune conditions in 11. Thirteen patients had been started on 20% serum tears at the time of review. At a mean follow-up of 2 years, 7 patients had full or near-full responses, 3 were lost to follow-up, and 3 did not respond. In responders, pain scores decreased from an average of 8.5 ± 1.64 to 0.6 ± 1.34, p = 0.0001. Responders had on average higher initial pain scores (8.5 ± 1.64 vs 6.3 ± 1.15, p = 0.084). Of the 3 non-responders all reported a smoking history and asymmetric symptoms, and 2 had psychiatric diagnoses. Of the 7 responders, only 3 had a smoking history, 1 had asymmetric symptoms, and 0 had psychiatric diagnoses. There were no observable differences between the two groups in race, age, or ocular comorbidities.
Conclusions :
Autologous serum tears were found to be effective in reducing CNP symptoms in 7/10 patients. Non-responders were more likely to have a lower pain score at presentation, asymmetric symptoms, psychiatric conditions, and a smoking history. Larger studies may help identify which CNP patients would benefit most from this treatment.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.