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Purpose To compare the diagnostic performance of an ophthalmology specific microarray PCR (iCAM) and metagenomic next-generation sequencing (mNGS) against conventional microbiological investigations in microbial keratitis.Methods Corneal epithelial scrapes from 65 patients with microbial keratitis were analysed using iCAM microarray PCR in this multicentre clinical trial ( ISRCTN17422545). Parallel samples underwent standard microbiological testing, including microscopy, culture, and monoplex PCR according to local protocol. Metagenomics sequencing was prepared using the Oxford Nanopore Rapid PCR barcoding kit and results compared to iCAM microarray. The turnaround time, microbial detection, concordance between modalities, and the influence of results on clinical decision-making were analysed in this study.Results iCAM microarray PCR identified the causative organism in three of four cases with the ability to detect bacteria, viruses, fungi and acanthamoeba using a single corneal epithelial sample. The iCAM test sensitivity, turnaround times and the positive predictive value of the test will be presented and compared to conventional microbiology results. The development of the metagenomics protocol and their role in identifying rare and fastidious organisms will be described in this presentation.Conclusion Microarray PCR and metagenomics have the potential to significantly improve microbial detection in infectious keratitis. The iCAM test could function as the first line screening test with mNGS reserved for iCAM negative cases and severe ocular infections.