In vivo imaging of the bronchial wall microstructure using fibered confocal fluorescence microscopy.
BACKGROUND
Fibered confocal fluorescence microscopy (FCFM) is a new technique that produces microscopic imaging of a living tissue through a 1-mm fiberoptic probe that can be introduced into the working channel of the bronchoscope.


OBJECTIVE
To analyze the microscopic autofluorescence structure of normal and pathologic bronchial mucosae using FCFM during bronchoscopy.


METHODS
Bronchial FCFM and spectral analyses were performed at 488-nm excitation wavelength on two bronchial specimens ex vivo and in 29 individuals at high risk for lung cancer in vivo. Biopsies of in vivo FCFM-imaged areas were performed using autofluorescence bronchoscopy.


RESULTS
Ex vivo and in vivo microscopic and spectral analyses showed that the FCFM signal mainly originates from the elastin component of the basement membrane zone. Five distinct reproducible microscopic patterns were recognized in the normal areas from the trachea down to the more distal respiratory bronchi. In areas of the proximal airways not previously biopsied, one of these patterns was found in 30 of 30 normal epithelia, whereas alterations of the autofluorescence microstructure were observed in 19 of 22 metaplastic or dysplastic samples, five of five carcinomas in situ, and two of two invasive lesions. Disorganization of the fibered network could be found on 9 of 27 preinvasive lesions, compatible with early disruptions of the basement membrane zone. FCFM alterations were also observed in a tracheobronchomegaly syndrome and in a sarcoidosis case.


CONCLUSIONS
Endoscopic FCFM represents a minimally invasive method to study specific basement membrane alterations associated with premalignant bronchial lesions in vivo. The technique may also be useful to study the bronchial wall remodeling in nonmalignant chronic bronchial diseases.
Thiberville
Luc
L
Clinique Pneumologique, Hôpital Charles Nicolle-CHU de Rouen, 1 rue de Germont, 76031 Rouen Cedex, France. luc.thiberville@univ-rouen.fr
Moreno-Swirc
Sophie
S
Vercauteren
Tom
T
Peltier
Eric
E
Cavé
Charlotte
C
Bourg Heckly
Genevieve
G
D001980:Bronchi / Q000648:ultrastructure*; D001984:Bronchial Neoplasms / Q000175:diagnosis / Q000648:ultrastructure*; D003952:Diagnostic Imaging; D005336:Fiber Optic Technology; D006801:Humans; D018613:Microscopy, Confocal / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*