Cresyl violet as a fluorophore in confocal laser scanning microscopy for future in-vivo histopathology

Confocal laser scanning microscopy appears to be a key technology for future endoluminal diagnostic tools for obtaining noninvasive optical biopsies. Until now, clinical use of this technique has been problematic, as successfully tested dyes are toxic. In the present study, cresyl violet acetate was evaluated as a nontoxic staining agent for in-vivo histopathology.

Esophageal and gastric mucosa from the swine was obtained and examined ex vivo with a commercially available confocal laser scanning microscope. A series of images was recorded for concentrations of cresyl violet ranging from 0.1 % to 10 % for both esophageal and gastric mucosa. Staining was carried out for 2 min after mucolysis with acetylcysteine.

Staining with 2 % cresyl violet led to identification of nuclei and cell membranes. Lower concentrations were associated with a lack of homogeneous dye absorption in particular in the gastric mucosa.

Cresyl violet is a clinically usable fluorophore for confocal laser scanning microscopy. Its use in combination with an endoluminally applicable system has the potential to allow in vivo histopathology.