Clinical observation of recombinant human nerve growth factor in the treatment of neurotrophic keratitis

AIM: To characterize changes of corneal nerve morphology and tear indices in patients with neurotrophic keratitis (NK) treated with recombinant human nerve growth factor (rhNGF).
METHODS: In a prospective observational study, six patients (nine eyes) were locally treated with rhNGF. Visual acuity, corneal fluorescein staining score, the heights of the tear river, lipid layer thickness (LLT), tear ferning (TF) test, conjunctival impression cytology (CIC) examination, the densities of cornea subbasal nerve fibers were determined before and after treatment.
RESULTS: Compared with baseline, there was a significant difference in corneal fluorescence staining scores (P<0.01); all patient corneal epithelial defects recovered completely within 8wk, but there was no significant improvement in the height of the tear river (P=0.202). LLT was significantly increased when compared with baseline (P=0.042); however, the function of conjunctival goblet cells and mucin content did not significantly improve using the TF test and CIC examination (P=0.557, P=0.539). After 8wk of treatment, the average corneal subbasal nerve fiber density increased significantly (P<0.01), as did the number of corneal nerve fiber branches (P=0.001).
CONCLUSION: RhNGF can increase the density of corneal subbasal nerve fibers, promote the healing of persistent corneal epithelial defects and corneal ulcers in patients with NK, also improving tear function partially.