Neurotrophic Keratitis Clinical Presentation

Updated: Sep 13, 2018
  • Author: Robert H Graham, MD; Chief Editor: Hampton Roy, Sr, MD  more...
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A careful medical and surgical history should be obtained. Inquire about the following:

  • Previous surgical or traumatic injury to the trigeminal nerve, ocular surgery, or laser treatment, which may have damaged the ciliary nerves

  • Previous herpetic eye disease or a history of herpes zoster ophthalmicus [7]

  • Diabetes mellitus [8]

  • Use of topical medications, including potential abuse of topical anesthetics or nonsteroidal anti-inflammatory drugs (NSAIDs)

  • Use of contact lenses

  • Exposure to chemical fumes


Physical Examination

Poor lid closure promotes exposure and can hasten progression, while the presence of scars from surgery, chemical burns, or thermal burns can provide clues as to the cause of the hypesthesia. Ectropion, lagophthalmos, or thyroid ophthalmopathy increase the risk of progression.

Cranial nerve examination

A cranial nerve examination can help to localize the cause of corneal hypesthesia. Pupillary abnormality may indicate pathology of the intraconal orbit or cavernous sinus or may reveal an Adie pupil. Dysfunction of cranial nerves III, IV, and VI may indicate an aneurysm or cavernous sinus pathology. Dysfunction of cranial nerves VII and VIII may indicate acoustic neuroma or injury from its resection.

Cranial nerve VII function should be assessed not only because of its value in localizing the cause of hypesthesia but also because of its prognostic value.

Ocular surface examination

The function of the tear film should be carefully examined for its impact on the management of neurotrophic keratitis. [10, 11] Corneal sensitivity should be assessed as well; to do so, a piece of twisted cotton or the corner of a tissue is used.


A Cochet-Bonnet esthesiometer is a device that can give a quantitative measurement of corneal sensitivity, a determination that is diagnostically and prognostically crucial.

The esthesiometer consists of a nylon filament, which can be extended from the device to different lengths and touched to the cornea until it bends or the patient responds. The small diameter of the instrument allows accurate testing of different areas of the cornea. The shorter the length of filament required, the less sensitive the cornea. In one study, only patients with readings of 2 cm or less developed epithelial sloughing and ulceration.

Slitlamp examination

Slitlamp examination may show indications of the underlying cause of corneal hypesthesia. These include herpetic epithelial disease, stromal scarring from previous infection, lattice or granular stromal dystrophy, and enlarged or beaded corneal nerves from leprosy.

Anterior segment examination

This may reveal iris atrophy from a prior herpetic infection or an anterior chamber inflammatory reaction.

Dilated funduscopy

Optic nerve swelling or pallor may indicate an orbital or retro-orbital lesion. Diabetic retinopathy could indicate the likelihood of diabetic neuropathy. Laser scars from panretinal photocoagulation may indicate ciliary nerve damage.