Evaluation of ocular neuropathic pain

Aim: To identify and assess the quality of current validated questionnaires that could be used to evaluate ocular neuropathic pain and its associated aetiologies.

Methods: A literature search was performed on MEDLINE, PubMed, EMBASE, PsycINFO and The Cochrane Library. Articles evaluating questionnaires for ocular neuropathic pain and its associated aetiologies were included. Data on psychometric properties, validity, and reliability of the questionnaires was extracted and analysed using a set of quality criteria. Clinical and demographical associations with ocular neuropathic pain were also reviewed.

Results: The search generated 1738 results with 61 publications meeting the inclusion criteria. The 61 publications covered 28 questionnaires including 3 for ocular pain, 12 dry eye disease, 2 blepharitis, 2 refractive surgery, 3 contact lens wear, 3 Sjogren’s Syndrome, and 3 that were non-disease-specific. Only 57 publications provided enough data on psychometric properties and validity of the questionnaire to be included for quality assessment. The Contact Lens Discomfort Index (CLDI) had the highest rated psychometric properties, whereas the English version of the Ocular Comfort Index (OCI) provided the most data on psychometric properties (9 out of 10 criteria). Most ocular pain and disease-specific questionnaires contained appropriate items to assess ocular pain in specific populations. However, non-disease-specific ophthalmic questionnaires demonstrated poor reliability and validity when evaluating ocular pain.

Conclusion: Ocular pain questionnaires can potentially diagnose ocular neuropathic pain. Disease-specific questionnaires are limited to their target populations, and non-disease-specific ophthalmic questionnaires are unreliable. Further studies are required to determine the most appropriate questionnaire to evaluate ocular neuropathic pain.

Keywords: Ocular neuropathic pain; Ocular pain; Patient-reported outcomes; Questionnaires.