Case Report
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Dec 16, 2015; 3(12): 993-999
Published online Dec 16, 2015. doi: 10.12998/wjcc.v3.i12.993
Histopathological confirmation of similar intramucosal distribution of fluorescein in both intravenous administration and local mucosal application for probe-based confocal laser endomicroscopy of the normal stomach
Kouichi Nonaka, Ken Ohata, Shinichi Ban, Shin Ichihara, Rumi Takasugi, Yohei Minato, Tomoaki Tashima, Yasushi Matsuyama, Maiko Takita, Nobuyuki Matsuhashi, Helmut Neumann
Kouichi Nonaka, Ken Ohata, Yohei Minato, Tomoaki Tashima, Yasushi Matsuyama, Maiko Takita, Nobuyuki Matsuhashi, Department of Gastroenterology, NTT Medical Center Tokyo, Tokyo 141-8625, Japan
Shinichi Ban, Department of Pathology, Dokkyo Medical University Koshigaya Hospital, Koshigaya 343-8555, Japan
Shin Ichihara, Department of Pathology, Sapporo-Kosei General Hospital, Sapporo 078-8212, Japan
Rumi Takasugi, Division of Technical Service, Kyodo Byori, Kobe 651-2112, Japan
Helmut Neumann, Department of Medicine 1, University of Erlangen-Nuremberg, 91054 Erlangen, Germany
Author contributions: Nonaka K and Ohata K designed the report; Ban S, Ichihara S and Takasugi R performed the pathological analyses; Minato Y, Tashima T, Matsuyama Y, Takita M and Matsuhashi N performed the examination; Nonaka K, Ban S and Neumann H analyzed the data and wrote the paper.
Supported by Japanese Foundation for Research and Promotion of Endoscopy.
Institutional review board statement: The institutional review board of NTT Medical Center Tokyo.
Informed consent statement: The written informed consent was obtained.
Conflict-of-interest statement: No potential conflicts of interest relevant to this article were reported.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Helmut Neumann, Department of Medicine 1, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany. helmut.neumann@uk-erlangen.de
Telephone: +49-913-18545053 Fax: +49-913-18353209
Received: July 17, 2015
Peer-review started: July 17, 2015
First decision: September 14, 2015
Revised: September 24, 2015
Accepted: October 20, 2015
Article in press: October 21, 2015
Published online: December 16, 2015
Processing time: 143 Days and 22.5 Hours
Abstract

Probe-based confocal laser endomicroscopy (pCLE) is capable of acquiring in vivo magnified cross-section images of the gastric mucosa. Intravenous injection of fluorescein sodium is used for confocal imaging. However, it is still under debate if local administration of the dye to the mucosa is also effective for confocal imaging as it is not yet clear if topical application also reveals the intramucosal distribution of fluorescein. The objective of this study was to evaluate the intramucosal distribution of fluorescein sodium after topical application and to compare the distribution to the conventional intravenous injection used for confocal imaging. pCLE of the stomach uninfected with Helicobacter pylori was performed in a healthy male employing intravenous administration and local mucosal application of fluorescein. The mucosa of the lower gastric body was biopsied 1 min and 5 min after intravenous administration or local mucosal application of fluorescein, and the distribution of fluorescein in the biopsy samples was examined histologically. Green fluorescence was already observed in the cytoplasm of fundic glandular cells in the biopsied deep mucosa 1 min after local mucosal application of fluorescein. It was also observed in the foveolar lumen and inter-foveolar lamina propria, although it was noted at only a few sites. In the tissue biopsied 5 min after the local mucosal application of fluorescein, green fluorescence was more frequently noted in the cytoplasm of fundic glandular cells than in that 1 min after the local mucosal application of fluorescein, although obvious green fluorescence was not identified in the foveolar lumen or inter-foveolar lamina propria. The distribution of intravenously administered fluorescein in the cytoplasm of fundic glandular cells was also clearly observed similarly to that after local mucosal application of fluorescein. Green fluorescence in more cells was observed in many cells 5 min after intravenous administration compared with that after 1 min. The presence of fluorescein in the mucosa was observed within a short time after local mucosal application of fluorescein, suggesting that pCLE images similarly to those after intravenous fluorescein administration can be acquired by local mucosal application of fluorescein.

Keywords: Confocal laser endomicroscopy; Fluorescein; Local application; Intravenous; Distribution

Core tip: In this study, we demonstrated the presence of fluorescein administered by local mucosal application in the lamina propria. We consider this study valuable because it demonstrated that confocal laser endomicroscopic images can be acquired by local mucosal application of fluorescein. In addition, the fluorescein distributions after intravenous administration and local mucosal application were the same, which is also of interest.