Anterior Segment Oct Features For Infectious Keratitis At First Admission: Does It Give A Clue About The Pathogen?

To investigate the anterior segment optical coherence tomography patterns in infectious keratitis and to evaluate the role of this tool in the early diagnosis of the pathogen before microbiological assessment.

Single tertiary care referral hospital (Basaksehir Cam and Sakura City Hospital)

Clinical records of Twenty-seven eyes of 27 patients who applied Basaksehir Cam and Sakura City Hospital Eye Casualty between January 2023 and February 2024 with the diagnosis of infectious keratitis were retrospectively reviewed. Anterior segment OCT images performed at the time of initial admission were evaluated. Corneal thickness (CT), hyperreflectivity-hyporeflectivity, endothelial and descement membrane thickening (EDMT), and corneal heterogenous reflectivity (CHR) were evaluated and compared with the confirmed microbiological results.

Bacterial keratitis (BK) was detected in 20 of 27 eyes (74.1%), and fungal keratitis (FK) was detected in 7 eyes (25.9%). In all 20 eyes with BK, an increase in CT, CHR, and hyperreflectivity in the infiltration area and hyporeflectivity under the lesion were observed,while an increase in EDMT was observed in 16 eyes. Furthermore, in 4 out of 20 eyes which had total corneal abscess, hyperreflectivity was more remarkable on the posterior corneal stroma in comparison with the anterior stroma.In 6 out of 7 eyes with FK, increased hyperreflectivity and irregularity were detected in the Bowman membrane and anterior stroma. However, no significant increase in CT was detected in 5 eyes, and no increase in EDMT was detected in any eye with FK.

Anterior segment OCT findings are valuable in infectious keratitis for gaining insight into the clinical diagnosis of the pathogen and initiating effective ampirical treatment early. This is particularly useful in cases where discrimination between bacterial and fungal keratitis is difficult.