Research

Video aims to standardise approach to corneal scrapes

Corneal scrapes are the standard procedure for diagnosing the causative agent in microbial keratitis, yet they are not formally taught to ophthalmology students. The animated video donstrates the best practice for obtaining a diagnostic sample from corneal scrapes, and depicts the culture medias and key steps required to increase the diagnostic yield from the procedure.One of the producers of the video, clinical research officer Ms Pauline Khoo, said it was needed as currently up to half of all corneal scrapes do not result in identifying the causal organism.{{quote-a:r-w:430-I:2-Q:“Knowledge of the technique and processing of samples are vital to ensure viable and reliable samples.”-WHO:Pauline Khoo, Clinical Research Officer}}“Despite correctly obtained corneal samples having the potential to save sight and reduce the burden of the disease from inappropriate therapy, there are no clear guidelines for how to collect such samples,” Khoo explained.“There is no formal training in the technique and registrars are typically taught by another registrar in the ergency setting. Typically, no masks or gloves are worn during corneal scraping, leading to confusion over throat and skin microbes that could be contaminants and interpreted as the source of the infection.”She added, “At times, labels are placed over the middle of the culture plate making the sample difficult to read for the microbiologist. Knowledge of the technique and processing of samples are vital to ensure viable and reliable samples.”Khoo said there are a number of reasons why the steps featured in the video – which were established using evidence-based guidelines and input from multiple senior and junior doctors, nurses, and microbiologists – are considered best practice.“They eliminate any chance of contaminants and ensure the organism or organisms identified are from the infected eye. Correct placent of labels on agar plates assist the microbiologist with identifying organisms and ensures specimens are processed appropriately,” Khoo said.“With no formal training provided on performing corneal scrapes, the video ensures standardisation amongst doctors. In addition, correcting handling of the plates which the organisms are cultured on, e.g. their roval from the fridge one hour before use, increases the chance of culturing the causal organism.”The SSI aims to produce more videos in future, as it believes they are a strong way of delivering educational messages.