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Purpose Corneal Impression Membrane (CIM) sampling is a minimally invasive technique for obtaining corneal samples in suspected microbial keratitis. Emerging evidence suggests CIM may improve microorganism detection compared to traditional corneal scraping. This study evaluated CIM versus scraping in terms of diagnostic yield, procedure time, patient comfort, and clinician preference.Methods Over a six-month period, consecutive patients presenting with presumed microbial keratitis underwent paired sampling, with both a standard corneal scrape and a corneal impression membrane applied to the same ulcer. All samples were processed by the same microbiology laboratory using standard culture protocols.Results CIM sampling demonstrated a significantly higher overall microorganism isolation rate compared to scraping (60% vs 31%, p < 0.001). Among routinely pathogenic organisms, CIM yielded higher isolation rates for Streptococcus pneumoniae and Serratia marcescens (10.5% vs 8%), with no significant difference in detection of Staphylococcus aureus or Pseudomonas aeruginosa. CIM also showed markedly higher recovery of common commensals, particularly Staphylococcus epidermidis. CIM sampling was significantly faster (mean 38 seconds vs 5 minutes 12 seconds, p<0.001), with all clinicians favouring its ease of use and consistency. Patient tolerance was also significantly higher with CIM (p<0.001).Conclusion CIM sampling improves the detection of both pathogenic and commensal microorganisms, significantly reduces sampling time, and is preferred by both clinicians and patients. These findings support its broader adoption as a first-line diagnostic method in microbial keratitis.