Résumés
Résumé
La tomographie par cohérence optique, plus communément appelée OCT (optical coherence tomography), est une technique d’imagerie non invasive des milieux biologiques à l’échelle du micromètre dont l’impact le plus remarquable concerne l’ophtalmologie. L’OCT « plein champ » est une approche originale de l’OCT, proposée et améliorée au fil des ans par notre équipe. Après avoir exposé le principe de l’OCT plein champ, nous détaillerons ses performances en soulignant les avantages et les inconvénients par rapport à l’OCT classique. Les potentialités de cette technique seront illustrées par quelques exemples d’applications dans les domaines de l’embryologie, la biologie du développement et l’ophtalmologie. Enfin, nous présenterons les développements en cours pour l’imagerie à très haute résolution in vivo, pour accroître la profondeur d’imagerie dans les milieux fortement diffusants, ou encore exploiter de nouvelles sources de contraste comme la biréfringence optique.
Summary
Optical coherence tomography (OCT) is an emerging technique for imaging of biological media with micrometer-scale resolution, whose most significant impact concerns ophthalmology. Since its introduction in the early 1990’s, OCT has known a lot of improvements and sophistications. Full-field OCT is our original approach of OCT, based on white-light interference microscopy. Tomographic images are obtained by combination of interferometric images recorded in parallel by a detector array such as a CCD camera. Whereas conventional OCT produces B-mode (axially-oriented) images like ultrasound imaging, full-field OCT acquires tomographic images in the en face (transverse) orientation. Full-field OCT is an alternative method to conventional OCT to provide ultrahigh resolution images (~ 1 µm), using a simple halogen lamp instead of a complex laser-based source. Various studies have been carried, demonstrating the performances of this technology for three-dimensional imaging of ex vivo specimens. Full-field OCT can be used for non-invasive histological studies without sample preparation. In vivo imaging is still difficult because of the object motions. A lot of efforts are currently devoted to overcome this limitation. Ultra-fast full-field OCT was recently demonstrated with unprecedented image acquisition speed, but the detection sensitivity has still to be improved. Other research directions include the increase of the imaging penetration depth in highly scattering biological tissues such as skin, and the exploitation of new contrasts such as optical birefringence to provide additional information on the tissue morphology and composition.
Parties annexes
Références
- 1. Huang D, Swanson EA, Lin CP, et al. Optical coherence tomography. Science 1991 ; 254 : 1178-81.
- 2. Fujimoto JG, Brezinski ME, Tearney GJ, et al. Optical biopsy and imaging using optical coherence tomography. Nat Med 1995 ; 1 : 970-2.
- 3. Fercher AF. Optical coherence tomography. J Biomed Opt 1996 ; 1 : 157-73.
- 4. Wojtkowski M, Leitgeb R, Kowalczyk A, et al. In vivo human retinal imaging by Fourier domain optical coherence tomography. J Biomed Opt 2002 ; 7 : 457-63.
- 5. Nassif N, Cense B, Park BH, et al.In vivo human retinal imaging by ultrahigh-speed spectral domain optical coherence tomography. Opt Lett 2004 ; 29 : 480-2.
- 6. Leitgeb RA, Drexler W, Unterhuber A, et al. Ultrahigh resolution Fourier domain optical coherence tomography. Opt Express 2004 ; 12 : 2156-65.
- 7. De Boer JF, Milner TE, Van Gemert MJC, Nelson JS. Two-dimensional birefringence imaging in biological tissue by polarization sensitive optical coherence tomography. Opt Lett 1997 ; 22 : 934-6.
- 8. Park BH, Saxer C, Srinivas SM, et al. In vivo burn depth determination by highspeed fiber-based polarization sensitive optical coherence tomography. J Biomed Opt 2001 ; 6 : 474-9.
- 9. Jiao S, Yao G, Wang LV. Two-dimensional depth-resolved Mueller matrix of biological tissue measured with double-beam polarization-sensitive optical coherence tomography. Opt Lett 2002 ; 27 : 101-3.
- 10. Chen Z, Miller TE, Srinivas S, et al. Noninvasive imaging of in vivo blood flow velocity using optical Doppler tomography. Opt Lett 1997 ; 22 : 1119-21.
- 11. Westphal V, Yazdanfar S, Rollins AM, Izatt JA. Real-time, high velocity-resolution color Doppler optical coherence tomography. Opt Lett 2002 ; 27 : 34-6.
- 12. Vabre L, Dubois A, Boccara AC. Thermal-light full-field optical coherence tomography. Opt Lett 2002 ; 27 : 530-2.
- 13. Dubois A, Grieve K, Moneron G, et al. Ultrahigh-resolution full-field optical coherence tomography. Appl Opt 2004 ; 43 : 2874-83.
- 14. Izatt JA, Hee MR, Owen GM, et al. Optical coherence microscopy in scattering media. Opt Lett 1994 ; 19 : 590-2.
- 15. Podoleanu AG, Rogers JA, Jackson DA, Dunne S. Three dimensional OCT images from retina and skin. Opt Express 2000 ; 7 : 292-8.
- 16. Hitzenberger CK, Trost P, Lo PW, Zhou Q. Three-dimensional imaging of the human retina by high-speed optical coherence tomography. Opt Express 2003 ; 11 : 2753-61.
- 17. Hitzenberger CK, Baumgartner A, Drexler W, Fercher AF. Dispersion effects in partial coherence interferometry : implications for intraocular ranging. J Biomed Opt 1999 ; 4 : 144-51.
- 18. Drexler W, Morgner U, Kärtner, et al. In vivo ultrahigh-resolution optical coherence tomography. Opt Lett 1999 ; 24 : 1221-3.
- 19. Swanson EA, Izatt JA, Hee MR, et al. In vivo retinal imaging by optical coherence tomography. Opt Lett 1993 ; 18 : 1864-6.
- 20. Perea-Gomez A, Moreau A, Camus A, et al. Initiation of gastrulation in the mouse embryo is preceded by an apparent shift in the orientation of the anterior-posterior axis. Curr Biol 2004 ; 14 : 197-207.
- 21. Grieve K, Paques M, Dubois A, et al. Ocular tissue imaging using ultrahigh-resolution full-field optical coherence tomography. Invest Ophthalmol Vis Sci 2004 ; 45 : 4126-31.
- 22. Dubois A, Moneron G, Grieve K, Boccara AC. Three-dimensional cellular-level imaging using full-field optical coherence tomography. Phys Med Biol 2004 ; 49 : 1227-34.
- 23. Schmitt J, Xiang SH, Yung KM. Differential absorption imaging with optical coherence tomography. J Opt Soc Am A 1998 ; 15 : 2288-96.
- 24. Schmitt JM, Knuttel A, Yadlowsky M, Eckhaus MA. Optical-coherence tomography of a dense tissue : statistics of attenuation and backscattering. Phys Med Biol 1994 ; 39 : 1705-20.
- 25. Grieve K, Dubois A, Simonutti M, et al.In vivo anterior segment imaging in the rat eye with high speed white light full-field optical coherence tomography. Opt Express 2005 ; 13 : 6286-95.
- 26. Moneron G, Boccara AC, Dubois A. Stroboscopic ultrahigh-resolution full-field optical coherence tomography. Opt Lett 2005 ; 30 : 1351-3.