Neuropathic corneal pain is a condition that causes your eyes, face or head to be over sensitive. It also causes them pain. This condition is also called corneal neuralgia. Doctors don't know the exact cause of neuropathic corneal pain. They think it results from nerve damage to the cornea combined with inflammation. This combination makes your nervous system not work correctly.
The condition is often misdiagnosed as dry eye disease. Left untreated, it can lead to severe and debilitating pain.
What Is Somatic Symptom Disorder?
Somatic symptom disorder causes extreme distress over pain and other physical conditions. In rare cases, somatic symptom disorder can lead to suicide. If you have somatic symptom disorder, the pain from neuropathic corneal pain can make your disorder worse.
Early diagnosis and treatment of neuropathic corneal pain can improve your outcome.
Neuropathic Corneal Pain Symptoms
Symptoms of neuropathic corneal pain that affect the eyes include:
- pain
- sensitivity to light and air
- foreign body sensation
- burning
- severe dryness in the eyes
Symptoms are not always restricted to the eyes. Areas around the eye share a nerve supply with the cornea. Some patients with this condition can feel pain or aching in the face, ears or head.
Symptoms of neuropathic corneal pain can sometimes overlap with dry eye disease. But patients with neuropathic corneal pain may not show dryness in an eye exam. People with neuropathic corneal pain usually do not respond to conventional dry eye therapies.
Causes of Neuropathic Corneal Pain
Any condition that results in corneal nerve damage can cause neuropathic corneal pain.
A small number of patients can develop the condition as a complication of:
Neuropathic corneal pain can also result from:
- chronic dry eye disease
- radiation therapy
- extended contact lens wear
- toxicity from preservatives
- shingles
- diabetes
- trigeminal neuralgia, a chronic condition that causes facial pain
- any systemic condition that can lead to nerve damage
Damaged nerves usually regenerate on their own. But untreated inflammation can make damaged nerves more sensitive. You and your ophthalmologist must address the injury and inflammation. If not, over time they can trigger inappropriate signals transmitted to and from the brain. The resulting pain resembles the phantom pain experienced by amputees.
Neuropathic corneal pain seems more common in patients with existing neurological or psychiatric problems. These conditions include:
- anxiety
- depression
- chronic migraines
- headaches
- fibromyalgia
- autoimmune disease
More research is needed to confirm this connection.
Neuropathic Corneal Pain Diagnosis
Doctors suspect neuropathic corneal pain when dry eye therapies and drops for pain don't improve symptoms. They use a specific high-powered microscope to perform confocal microscopy to diagnose it. This microscope allows an ophthalmologist or neurologist to see nerve abnormalities. These are special microscopes that many practices don’t have. The technology is available in some academic centers and large multi-specialty private practices. You may need to travel to get this test.
“Often, people with neuropathic corneal pain are told that what they are feeling is ‘in their head.’ It is important that these individuals do not give up, but instead seek another opinion,” says Pedram Hamrah, an ophthalmologist and corneal specialist at Tufts Medical Center.
Neuropathic Corneal Pain Treatment
Treatment for neuropathic corneal pain has two aims:
- to regenerate nerves
- to reduce inflammation that makes nerves more sensitive
Treatments can include:
- eye drops made with the patient’s own blood (autologous serum tears)
- low-dose anti-inflammatory steroids
- amniotic membrane lenses
- neurostimulation
- blue filter glasses
- systemic neuro-modulatory therapies
- topical recombinant corneal nerve growth factor
Other treatments are in development.
Dr. Hamrah advises that the less time from diagnosis to treatment, the more chance a patient has of getting complete relief from neuropathic corneal pain.