<unk>  (NK) is a degenerative disease of the cornea caused by damage of the trigeminal nerve, which results in impairment of corneal sensitivity, spontaneous corneal epithelium breakdown, poor corneal healing and development of corneal ulceration, melting and perforation. This is because, in addition to the primary sensory role, the nerve also plays a role maintaining the integrity of the cornea by supplying it with trophic factors and regulating tissue metabolism.<unk>  is classified as a rare disease, with an estimated prevalence of less than 5 in 10,000 people in Europe. It has been recorded that on average, 6% of herpetic keratitis cases may evolve to this disease, with a peak of 12.8% of cases of keratitis due to varicella zoster virus. The diagnosis, and particularly the treatment of<unk>  are the most complex and challenging aspects of this disease, as a satisfactory therapeutic approach is not yet available.
Neurotrophic keratitis
Nummular keratitis
Fungal keratitis
Peripheral ulcerative keratitis
Interstitial keratitis
Fuchs heterochromic iridocyclitis
Lattice corneal dystrophy
Subepithelial mucinous corneal dystrophy