Evaluation of the therapeutic effect of autologous serum on neurotrophic keratopathy with persistent corneal epithelial defect

Objective

To evaluate the outcomes of autologous serum eye drops on persistent corneal epithelial defect caused by neurotrophic keratopathy (NK).

Methods

An observational case series study was performed.Twenty patients (20 eyes) diagnosed with NK and persistent corneal epithelial defect were enrolled in Beijing Tongren Hospital from January 2020 to January 2021.The affected eyes were graded according to the severity of the lesion and received individualized comprehensive treatment with domestic autologous serum eye drops as the main therapy.The healing time of the corneal epithelial defect after treatment was recorded.The diameter and area of the defect were marked by corneal fluorescein staining.Changes in the diameter and area of the defect before treatment and at 1, 2, 3, 4 and 8 weeks after treatment were observed by slit lamp microscopy at 10×.Logarithm of the minimum angle of resolution (LogMAR) visual acuity was recorded with a standard logarithmic visual chart before treatment and at 1, 2, 4, 12, and 24 weeks after treatment.Changes in corneal nerve fiber distribution and silk length of corneal perception were assessed by confocal laser scanning microscopy and Cochet-Bonnet esthesiometry, respectively, before treatment and at 4, 12, and 24 weeks after treatment.Influences of corneal defect characteristics on the healing time were analyzed by multiple linear regression analysis.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Beijing Tongren Hospital Affiliated to Capital Medical University (No.TRECKY2021-110). Written informed consent was obtained from each subject.

Results

The corneal epithelial defect was 5.00 (4.00, 5.75) mm in diameter and 15.50 (12.00, 20.00) mm² in area before treatment.There were 45% (9/20) with corneal stroma edema and 35% (7/20) with endothelial fold.One diabetic patient with uveitis had a corneal epithelial defect area greater than 8 mm×6 mm and accepted additional corneal clearance and amniotic membrane transplantation after 2 weeks of autologous serum eye drops application.The other 19 patients received autologous serum eye drops therapy.All eyes showed complete recovery.The pretreatment duration of autologous serum eye drops ranged from 2 weeks to 3 months, with a mean of (39.55±25.34) days.The repair time of corneal epithelium ranged from 12 to 42 days, with a mean of (19.68±9.25) days.There were statistically significant differences in corneal defect diameter and area between before and after treatment (χ²=43.130, 28.265; both at P<0.001). Corneal defect area and diameter decreased at various time points after treatment compared to before treatment, and the differences were statistically significant (all at P<0.05). There were statistically significant differences in LogMAR visual acuity between before and after treatment (χ²=84.229, P<0.001). LogMAR visual acuity improved at 1, 2, 4, 12, and 24 weeks after treatment compared to pretreatment, and the differences were statistically significant (all at P<0.05). There were statistically significant differences in silk length of corneal perception between before and after treatment (χ²=55.295, P<0.001). Silk length of corneal perception improved at 4, 12 and 24 weeks compared to pretreatment, and the differences were statistically significant (all at P<0.05). Baseline corneal defect severity grade was positively correlated with healing time (β=10.55, P=0.032). Corneal defect diameter and area had no influence on the healing time (β=-2.02, P=0.501; β=0.49, P=0.199).

Conclusions

Autologous serum eye drop therapy is safe and effective for persistent corneal defects caused by NK.Re-application of autologous serum eye drops is still effective in individual patients with recurrent corneal defects after discontinuation of serum treatment.It can be combined with surgery for intractable cases.

Neurotrophic keratopathy; Persistent corneal epithelial defect; Autologous serum; Corneal sensation