Fluorescein pen: a novel tool with good ease of use for corneal fluorescein staining

Abstract

Background The purpose of this study was to validate a fluorescein pen for use in corneal staining and to compare this novel technique with two conventional tools. Methods An insulin pen was converted into a fluorescein pen for use in corneal staining. The fluorescein pen was provided to 15 ophthalmologists for evaluating the ease of use as compared with two other tools (standard fluorescein strips and the 1 mL syringe method). Each fluorescein pen was used multiple times and underwent microbiological cultivation weekly. If the microbial culture was negative, the pen was used until the fluorescein in the cartridge was used up. Cornea fluorescein staining with three tools was conducted on 16 patients. Images were taken under slit lamp cobalt blue light to assess image quality and consistency. Results The average application span for the fluorescein pen was 87.7 ± 17.0 days (n = 15). No microbial growth was detected in any sample during the application period. Ophthalmologists’ assessments for ease of use via evaluation scores on a five-point Likert scale were 4.933 ± 0.26, 2.6 ± 0.83, and 2.2 ± 0.68 for the pen, strips, and syringe method, respectively. The fluorescein pen demonstrated greater ease of use than the other two tools (p < 0.0001). Image quality and consistency using the fluorescein pen were improved as compared with the other two tools. Conclusions We conclude that the fluorescein pen has several advantages over traditional staining methods, including greater ease of use, safety for multiple uses, and better yield in terms of improved corneal staining images.