The evaluation of clinical efficacy of debridement and medication for fungal keratitis by means of confocal microscopy

Abstract

Objective To evaluate the clinical efficacy of debridement and medication for fungal keratitis by means of confocal microscopy. Methods The data of 19 eyes of 19 patients who had plant injury history and had been diagnosed as fungal keratitis were analysed retrospectively. The patients were examined by laser confocal microscopy firstly, and then by corneal scraping test to find fungal hyphae. The detection rates of two different methods were compared. The 19 patients were randomly divided into treatment group (9 eyes) and control group (10 eyes), and patients of both groups received conventional corneal debridement and antifungal agents. After confirming the lesions without fungal hyphae by repeated laser confocal microscopy examination, patients in the treatment group received corticosteroid, combined with non-steroidal anti-inflammatory medicine; patients in the control group was only given antifungal eye drops. The average corneal epithelial healing time, BCVA were measured and compared between the two groups. And the changes of the number of inflammatory cells and corneal stromal cells recorded by laser confocal microscopy. Results In the 19 eyes, fungal hyphae were detected on 17 eyes by confocal laser scanning microscopy, and the positive rate was 89.4%. 16 eyes were detected by corneal scraping, and the positive rate was 84.2%. There was no statistically significant difference between them (χ2=0.230, P=0.631). The corneal epithelial healing time in treatment group was (12.1±2.4) d, and it was (15.1±3.2) d in control group, the difference was statistically significant (t=-2.290, P=0.035). The difference in the BCVA 1 week, 3 weeks, 1 month and 3 months after treatment between the two groups were statistically significant (P=0.0000~0.0020), the treatment group showed better BCVA. In the treatment group, after using corticosteroid combined with non-steroidal anti-inflamming medicine, the number of inflamming cell decreased significantly and the corneal stromal cells tended to be normal. Conclusion After debridement and no fungal hyphae confirmed by laser confocal microscopy, the corticosteroid can promote epithelial healing and reduce inflammation. Laser confocal microscopy is a fast, effective and non-invasive biopsy methods. It plays an important role in the diagnosis, treatment and research in fungal keratitis. Key words: Keratitis, fungal; Medicine; Debridement; Laser scanning confocal microscopy