Welcome back to Dry Eye Fireside Chat. In this episode, Damon Dierker, OD, FAAO, sits down with Neel S. Vaidya, MD, MPH, MBA, to explore the prevalence, diagnosis, and current/emerging treatments for neurotrophic keratitis (NK).
From his 5 years in practice, Dr. Neel Vaidya—a Chicago cornea, cataract, and refractive specialist—has witnessed an increase in the diagnosis of NK and gleaned invaluable insights into the disease. Here are a few of the many observations he offered on NK.
What is neurotrophic keratitis?
Characterized by decreased corneal sensation, NK is historically a rare but potentially sight-threatening degenerative disease of the corneal surface caused by impaired sensory innervation. This loss of corneal sensation disrupts normal healing processes, leading to epithelial breakdown, persistent defects, and, in advanced cases, corneal ulcers or perforation.
Underlying conditions—including diabetes, shingles, herpes zoster, use of preserved glaucoma medications—increase the risk for NK.1 Based on a retrospective analysis of visits associated with a diagnosis of NK between 2013 and 2018 using the IRIS (American Academy of Ophthalmology's Intelligent Research in Sight) Registry, the prevalence of NK is 21.34 cases per 100,000 patients.2
This translates to approximately 70,000 people in the United States.1,3 It is highly probable that the true prevalence of NK is underestimated, as many early or mild cases go undiagnosed. However, this is changing with an increasing number of ophthalmologists and optometrists diagnosing NK in its earliest stages.
The connection between NK and dry eye
Neurotrophic keratitis has become an increasingly recognized condition in clinical practice, particularly in the context of dry eye disease. What was once considered a rare diagnosis is now seen with growing frequency, especially as awareness, diagnostic vigilance, and treatment options have improved. Dr. Vaidya noted that once he started looking for NK, he began finding it everywhere.
He added that, in the past, NK was typically only identified at more advanced stages 2 and 3, but today, clinicians are identifying earlier-stage disease more often. With effective treatments and emerging therapies available, early diagnosis has become more worthwhile, and ophthalmologists are increasingly attuned to detecting NK earlier in its course.
It has long been recognized that dry eye disease (DED) and NK are interconnected, but this relationship is still not fully understood. The chronic inflammation, mechanical stress, and tear film instability associated with DED can contribute to damage to the corneal nerves.
Conversely, patients with NK often exhibit signs of dry eye because the impaired corneal innervation disrupts normal tear production and the blink reflex, thereby worsening ocular surface dryness.4 Dr. Vaidya points out that the challenge is in determining which came first, similar to the classic chicken or egg dilemma.
Does dry eye cause NK? Drs. Dierker and Vaidya discuss in the full interview.
What are treatment options for neurotrophic keratitis?
Dr. Vaidya recommended that eyecare practitioners be intentional about looking for NK, as there are now great treatment options available. In his clinic, patients with corneal complaints, individuals referred for premium intraocular lens (IOL) surgery, and those seeking a DED second opinion all undergo evaluation to determine if stage 1 NK is present.
Checking corneal sensitivity has become a routine part of the exam for any patient presenting with corneal complaints, even if NK isn’t initially suspected. Therefore, as part of the diagnostic workflow, no eye drops are administered prior to examination, so the cornea can be assessed in its natural state.
This allows for accurate evaluation at the slit lamp of tear breakup time, staining patterns, and subtle ocular surface abnormalities. Management of neurotrophic keratitis, particularly when accompanied by dry eye disease, requires a stepwise and proactive approach.
First-line treatments for NK typically include:
- Preservative-free artificial tears
- Punctal plugs to retain natural tears
- Lid hygiene
- Doxycycline for meibomian gland dysfunction
- Intense pulsed light (IPL) therapy
Managing advanced neurotrophic keratitis
Once foundational therapies are in place, escalation to anti-inflammatory treatments—such as topical cyclosporine or short-term corticosteroids—is often necessary, given the inflammation common in these patients.
For more refractory or advanced cases, clinicians should consider regenerative therapies like:
- Amniotic membranes
- Autologous serum tears
- Platelet-rich plasma
- Topical biologics like cenegermin (Oxervate)
Emerging therapies like topical insulin and thymosin β4, known for promoting wound healing, show significant promise. According to Dr. Vaidya, “I think if topical insulin becomes a commercially available product, that could be really useful. It would be along the same lines as serum tears, but maybe even more potent. And I'm a huge fan of serum tears, but they don't work for everybody. I think insulin might be kind of the next step up.”
In severe cases, where surgical intervention is necessary, Dr. Vaidya has seen great success with corneal neurotization, where the cornea has been saved to the degree that the patient may be eligible for a future transplant.
In conclusion
Advances in diagnostics, increased clinical awareness, and new treatment options now offer improved outcomes for those with NK, emphasizing the importance of early detection and intentional screening in at-risk populations.
Early recognition and understanding of the link between NK and DED are allowing optometrists and ophthalmologists to render treatments to slow or stop the progression of this vision-threatening disease.
