Factors affecting the prevalence, severity, and characteristics of ocular surface pain

ABSTRACT

Introduction

Ocular surface pain has been traditionally lumped under the umbrella term ‘dry eye’ (DE) but is now understood as its own entity and can occur in the absence or presence of tear dysfunction. Identifying patients at risk for the development of chronic ocular surface pain, and factors contributing to its severity are important in providing precision medicine to patients.

Areas covered

In this review, we discuss factors linked to the presence and severity of ocular surface pain, including eye-related features, systemic characteristics, and environmental findings. We discuss corneal nerves, whose anatomic and functional integrity can be characterized through in vivo confocal microscopy images and testing of corneal sensitivity. We review systemic diseases that are comorbid with ocular surface pain, including physical and mental health diagnoses. Finally, we identify environmental contributors, including air pollution, previous surgeries, and medications, associated with ocular surface pain.

Expert opinion

Intrinsic and extrinsic factors contribute to ocular surface pain and must be considered when evaluating an individual patient. These factors can inform the suspected etiology of the pain, and guide management decisions such as tear replacement or medications targeting nerve pain.

KEYWORDS:

• Ocular surface pain
• pain
• dry eye
• neuropathic pain
• nociceptive pain
• nerve sensitization
• hyperalgesia

Article highlights

• Ocular surface pain can occur due to nociceptive stimuli or neuropathic dysfunction

• Increased corneal sensitivity, representative of hyperalgesia, is a clinical sign of neuropathic pain

• The presence of systemic pain conditions, gender, poor sleep patterns, a heightened emotional state, and maladaptive coping mechanisms are factors beyond the ocular surface that may impact ocular surface pain presentation

• Environmental factors such as pollution and climate have been associated with ocular surface pain in large population-level studies

• Ocular surgeries and medication may contribute to nerve remodeling and contribute to ocular surface pain

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was funded by The Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Clinical Sciences R&D (CSRD) I01 CX002015 (A Galor), Biomedical Laboratory R&D (BLRD) Service I01 BX004893 (A Galor), Rehabilitation R&D (RRD) I21 RX003883 (E Felix), Department of Defense Gulf War Illness Research Program (GWIRP) W81XWH-20-1-0579 (A Galor) and Vision Research Program (VRP) W81XWH-20-1-0820 (A Galor), National Eye Institute R01EY026174 (A Galor) and R61EY032468 (A Galor), NIH Center Core Grant P30EY014801 (institutional) and Research to Prevent Blindness Unrestricted Grant GR004596 (institutional).