Pump-probe optical coherence tomography using indocyanine green as a contrast agent

Use of indocyanine green (ICG), an FDA-approved dye, in a pump-probe scheme for optical coherence tomography (OCT) is reported. Aqueous solutions of ICG are not stable, i.e., the dye degrades over time especially in the presence of light. Addition of protein such as bovine serum albumin (BSA) stabilizes the ICG; however, when exposed to high intensity illumination, the dye still degrades. Moreover, the photodegradation is permanent and occurs swiftly if the illumination band corresponds to the ICG absorption peak. The permanence of the photobleached state illustrates that ICG photobleaching phenomenon has great potential to achieve contrast in OCT. ICG solutions with 50 micromolar concentration were prepared in water, 1% BSA, and 0.8% agarose to study the dynamics of the dye for different illumination intensity levels. In addition, different molar concentrations of ICG in water were studied for fixed illumination intensity. In each case, probability of photobleaching, defined as the ratio of the total photobleached ICG molecules to the total photons absorbed by the ground-state molecules, is evaluated to characterize the photobleaching phenomenon in ICG. We also demonstrate ICG-based pump-probe MCOCT imaging by mapping the distribution of ICG in a stage 54 Xenopus laevis.

[1]  Teresa C. Chen,et al.  In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography , 2003 .

[2]  Maciej Wojtkowski,et al.  Complex spectral OCT in human eye imaging in vivo , 2004 .

[3]  Siavash Yazdanfar,et al.  Molecular contrast in optical coherence tomography by use of a pump-probe technique. , 2003, Optics letters.

[4]  Yingtian Pan,et al.  Detection of tumorigenesis in urinary bladder with optical coherence tomography: optical characterization of morphological changes. , 2002, Optics express.

[5]  J. Fujimoto,et al.  Spectroscopic optical coherence tomography. , 2000 .

[6]  J. Fujimoto,et al.  Optical coherence tomography of the human retina. , 1995, Archives of ophthalmology.

[7]  Guillermo J. Tearney,et al.  Atherosclerotic plaque characterization by spatial and temporal speckle pattern analysis , 2001, CLEO 2001.

[8]  E. Halpern,et al.  Evaluation of intracoronary stenting by intravascular optical coherence tomography , 2003, Heart.

[9]  M. Urashima,et al.  Infrared ray electronic endoscopy combined with indocyanine green injection for detection of sentinel nodes of patients with gastric cancer , 2004, The British journal of surgery.

[10]  B. Colston,et al.  Birefringence characterization of biological tissue by use of optical coherence tomography. , 1998, Optics letters.

[11]  S. Boppart,et al.  Nonlinear optical contrast enhancement for optical coherence tomography. , 2003, Optics express.

[12]  J. Izatt,et al.  Real-time in vivo imaging of human gastrointestinal ultrastructure by use of endoscopic optical coherence tomography with a novel efficient interferometer design. , 1999, Optics letters.

[13]  J. Nelson,et al.  Characterization of dentin and enamel by use of optical coherence tomography. , 1999, Applied optics.

[14]  J. Català Mora,et al.  Photodynamic Therapy for Chronic Central Serous Chorioretinopathy , 2004 .

[15]  Joseph A Izatt,et al.  Protein-based molecular contrast optical coherence tomography with phytochrome as the contrast agent. , 2004, Optics letters.

[16]  Joseph A Izatt,et al.  Spectral triangulation molecular contrast optical coherence tomography with indocyanine green as the contrast agent. , 2004, Optics letters.

[17]  Changhuei Yang,et al.  Pump-probe scheme for optical coherence tomography using indocyanine green mixed with albumin or human plasma , 2005, (CLEO). Conference on Lasers and Electro-Optics, 2005..

[18]  C K Hitzenberger,et al.  Spectral measurement of absorption by spectroscopic frequency-domain optical coherence tomography. , 2000, Optics letters.

[19]  J. Schuman,et al.  Optical coherence tomography. , 2000, Science.

[20]  Christoph Abels,et al.  Photo-isomerisation, triplet formation, and photo-degradation dynamics of indocyanine green solutions , 1999 .