Evaluating and Managing Neuropathic Corneal Pain

Ocular discomfort is one of the most common reasons patients see an ophthalmologist, noted Anat Galor MD, associate professor of ophthalmology at the Bascom Palmer Eye Institute in Miami, during the American Academy of Ophthalmology’s 2018 annual meeting in Chicago. 

Neuropathic corneal pain (NCP) is typically experienced by individuals between 40 and 70 years of age (average age 55). It is more prevalent in women. Symptoms include pain (experienced by 65%, according to Dr Galor’s data); light sensitivity (31%); discomfort (9%); and burning (6%).  More than one-fourth report experiencing two or more symptoms. 

Pain can lead to decreased autonomy, impaired physical and social function, decreased quality of life, dignity challenges, and increased physical suffering. It causes physiological effects, including sleep deprivation, anxiety and depression, tachycardia and elevated blood pressure, suicidal thoughts, weakness and muscle breakdown, increased sodium and water retention, decreased limb movement, respiratory issues, and decreased GI motility. 

Evaluating patients with ocular pain begins with patient observation, including blink rate; use of tissues for blotting, and light sensitivity. Also ask about cell phone gaming habits. Next, assess the ocular surface, including tear breakup time and corneal sensation. Remember to flip the lid. During the assessment, be sure to check for superior limbic keratoconjunctivitis, Salzmann’s nodular degeneration, and lid imbrication syndrome. These can sometimes be missed.

Next, evaluate the potential sources of pain, using the following techniques:

• Palpate
• Evaluate the effect of topical or peribulbar anesthesia
• Trials of cycloplegia, corticosteroids, migraine medication 
• Perform MRI of orbits, sinuses, central nervous system, and cervical spine
• Try 24/7 patching

It is important to remember that perceived ocular surface pain may originate elsewhere, including in the blood vessels, sinuses, cervical spine, extra-ocular muscles, iris/ciliary body, lids, and forehead. 

Finally, it is important to manage underlying conditions:

• Reduce exposure/evaporative tear loss
• Manage meibomitis
• Reduce/eliminate medication toxicity
• Discontinue contact lens use
• Correct conjunctival chalasis

There are a number of treatment approaches, but Dr. Galor noted that strategy is more important than the specific approach. A multimodal approach is key. Collaborate with other clinicians, including pain specialists for complex regional pain syndrome and fibromyalgia. Treatment should reduce peripheral signaling and restore central gating mechanism. 

Galor A. Ocular surface pain: Principles and practice. Talk presented at: AAO 2018 annual meeting; October, 26-30, 2018; Chicago.