title: High-resolution handheld rigid endomicroscope based on full-field optical coherence tomography.
abstract: Full-field optical coherence tomography (FF-OCT) is a powerful tool for nondestructive assessment of biological tissue, i.e., for the structural examination of tissue in depth at a cellular resolution. Mostly known as a microscopy device for ex vivo analysis, FF-OCT has also been adapted to endoscopy setups since it shows good potential for in situ cancer diagnosis and biopsy guidance. Nevertheless, all the attempts to perform endoscopic FF-OCT imaging did not go beyond lab setups. We describe here, to the best of our knowledge, the first handheld FF-OCT endoscope based on a tandem interferometry assembly using incoherent illumination. A common-path passive imaging interferometer at the tip of an optical probe makes it robust and insensitive to environmental perturbations, and a low finesse Fabry-Perot processing interferometer guarantees a compact system. A good resolution (2.7 μm transverse and 6 μm axial) is maintained through the long distance, small diameter relay optics of the probe, and a good signal-to-noise ratio is achieved in a limited 100 ms acquisition time. High-resolution images and a movie of a rat brain slice have been recorded by moving the contact endoscope over the surface of the sample, allowing for tissue microscopic exploration at 20 m under the surface. These promising ex vivo results open new perspectives for in vivo imaging of biological tissue, in particular, in the field of cancer and surgical margin assessment.
authors: LLTech, Pépinière Paris Santé Cochin, 29 rue du Faubourg Saint-Jacques, 75014 Paris, France.
authors: Emilie
authors: E
authors: Benoit a la Guillaume
authors: LLTech, Pépinière Paris Santé Cochin, 29 rue du Faubourg Saint-Jacques, 75014 Paris, France.
authors: Franck
authors: F
authors: Martins
authors: LLTech, Pépinière Paris Santé Cochin, 29 rue du Faubourg Saint-Jacques, 75014 Paris, FrancebESPCI ParisTech, PSL Research University, UMR 7587 CNRS, U979 INSERM, Institut Langevin, 1 rue Jussieu, 75005 Paris, France.
authors: Claude
authors: C
authors: Boccara
authors: LLTech, Pépinière Paris Santé Cochin, 29 rue du Faubourg Saint-Jacques, 75014 Paris, France.
authors: Fabrice
authors: F
authors: Harms
mesh_terms: D000818:Animals; D001706:Biopsy; D001921:Brain / Q000473:pathology; D004724:Endoscopy / Q000379:methods*; D004867:Equipment Design; D007091:Image Processing, Computer-Assisted; D007368:Interferometry / Q000379:methods*; D008853:Microscopy / Q000379:methods*; D051381:Rats; D041623:Tomography, Optical Coherence / Q000379:methods*