Assessment of the use of anterior segment optical coherence tomography in microbial keratitis

PURPOSE: To investigate the imaging capabilities of anterior segment optical coherence tomography (AS OCT) in microbial keratitis and to assess whether measurements of the quantitative parameters, infiltrate thickness and corneal thickness, were possible. DESIGN: Prospective, noncomparative, observational case series. METHODS: The study was conducted at a university hospital clinical setting. Seven patients (eyes) with suspected microbial keratitis underwent standard clinical examination and treatment based on slit-lamp clinical findings. AS OCT scanning was performed on presentation and at two follow-up appointments. All scans were carried out with the scanning beam passing through the center of the infiltration and at a specific meridian. Examination was carried out by the same operator. RESULTS: Corneal infiltration was imaged as a hyperreflective area in the corneal stroma on high-resolution AS OCT scans. Retrocorneal pathologic features and anterior chamber inflammatory cells could be imaged. Corneal and infiltrate thickness could be measured with calipers in six cases. In one case, corneal and infiltrate thickness could not be measured because of a thick inflammatory plaque attached to the endothelium. In this case, the width of the plaque was measured on serial scans. CONCLUSIONS: AS OCT imaging provides a range of parameters that can be used to assess microbial keratitis and the treatment response objectively.