Abstract

Image acquisition speed of optical coherence tomography (OCT) remains a fundamental barrier that limits its scientific and clinical utility. Here we demonstrate a novel multi-camera adaptive optics (AO-)OCT system for ophthalmologic use that operates at 1 million A-lines/s at a wavelength of 790 nm with 5.3 μm axial resolution in retinal tissue. Central to the spectral-domain design is a novel detection channel based on four high-speed spectrometers that receive light sequentially from a 1 × 4 optical switch assembly. Absence of moving parts enables ultra-fast (50ns) and precise switching with low insertion loss (−0.18 dB per channel). This manner of control makes use of all available light in the detection channel and avoids camera dead-time, both critical for imaging at high speeds. Additional benefit in signal-to-noise accrues from the larger numerical aperture afforded by the use of AO and yields retinal images of comparable dynamic range to that of clinical OCT. We validated system performance by a series of experiments that included imaging in both model and human eyes. We demonstrated the performance of our MHz AO-OCT system to capture detailed images of individual retinal nerve fiber bundles and cone photoreceptors. This is the fastest ophthalmic OCT system we know of in the 700 to 915 nm spectral band.

© 2014 Optical Society of America

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References

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2014 (1)

2013 (2)

2012 (2)

2011 (2)

2009 (2)

2008 (2)

2007 (2)

M. Mujat, B. H. Park, B. Cense, T. C. Chen, and J. F. de Boer, “Autocalibration of spectral-domain optical coherence tomography spectrometers for in vivo quantitative retinal nerve fiber layer birefringence determination,” J. Biomed. Opt. 12(4), 041205 (2007).
[Crossref] [PubMed]

S. A. Burns, R. Tumbar, A. E. Elsner, D. Ferguson, and D. X. Hammer, “Large-field-of-view, modular, stabilized, adaptive-optics-based scanning laser ophthalmoscope,” J. Opt. Soc. Am. A 24(5), 1313–1326 (2007).
[Crossref] [PubMed]

2006 (1)

2003 (3)

1998 (1)

1991 (1)

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

An, L.

Bouma, B. E.

Brown, J. M.

Burns, S. A.

Cable, A.

Cable, A. E.

Cense, B.

Chang, W.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Chen, T. C.

M. Mujat, B. H. Park, B. Cense, T. C. Chen, and J. F. de Boer, “Autocalibration of spectral-domain optical coherence tomography spectrometers for in vivo quantitative retinal nerve fiber layer birefringence determination,” J. Biomed. Opt. 12(4), 041205 (2007).
[Crossref] [PubMed]

Chen, Y.

Choi, S. S.

Choma, M.

de Boer, J. F.

Derby, J. C.

Duker, J. S.

Elsner, A. E.

Fercher, A.

Ferguson, D.

Ferguson, R. D.

Flotte, T.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Fujimoto, J. G.

Gao, W.

Gora, M.

Gorczynska, I.

Gregory, K.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Grulkowski, I.

Hammer, D. X.

Hee, M. R.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Herde, A. E.

Hitzenberger, C.

Huang, D.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Huber, R.

Izatt, J.

Jayaraman, V.

Jiang, J.

Jones, S. M.

Jonnal, R. S.

Kampik, A.

Kim, D. Y.

Klein, T.

Kocaoglu, O. P.

Kowalczyk, A.

Kulkarni, M.

Lee, S.

Leitgeb, R.

Li, P.

Lin, C. P.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Liu, J. J.

Liu, Z.

Lu, C. D.

Marcos, S.

Miller, D. T.

Moon, S.

Mujat, M.

B. Cense, W. Gao, J. M. Brown, S. M. Jones, R. S. Jonnal, M. Mujat, B. H. Park, J. F. de Boer, and D. T. Miller, “Retinal imaging with polarization-sensitive optical coherence tomography and adaptive optics,” Opt. Express 17(24), 21634–21651 (2009).
[Crossref] [PubMed]

M. Mujat, B. H. Park, B. Cense, T. C. Chen, and J. F. de Boer, “Autocalibration of spectral-domain optical coherence tomography spectrometers for in vivo quantitative retinal nerve fiber layer birefringence determination,” J. Biomed. Opt. 12(4), 041205 (2007).
[Crossref] [PubMed]

Neubauer, A.

Park, B. H.

Pierce, M. C.

Podoleanu, A. G.

A. G. Podoleanu, “Optical coherence tomography,” J. Microsc. 247(3), 209–219 (2012).
[Crossref] [PubMed]

Potsaid, B.

Puliafito, C. A.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Reznicek, L.

Rollins, A.

Sarunic, M.

Schuman, J. S.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Shen, T. T.

Srinivasan, V. J.

Stinson, W. G.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Swanson, E. A.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Szkulmowski, M.

Szlag, D.

Tearney, G. J.

Tumbar, R.

Ung-Arunyawee, R.

Wang, Q.

Wang, R.

Werner, J. S.

Wieser, W.

Wojtkowski, M.

Yang, C.

Yazdanfar, S.

Zawadzki, R. J.

Zhang, Y.

Biomed. Opt. Express (6)

J. Biomed. Opt. (1)

M. Mujat, B. H. Park, B. Cense, T. C. Chen, and J. F. de Boer, “Autocalibration of spectral-domain optical coherence tomography spectrometers for in vivo quantitative retinal nerve fiber layer birefringence determination,” J. Biomed. Opt. 12(4), 041205 (2007).
[Crossref] [PubMed]

J. Microsc. (1)

A. G. Podoleanu, “Optical coherence tomography,” J. Microsc. 247(3), 209–219 (2012).
[Crossref] [PubMed]

J. Opt. Soc. Am. A (1)

Opt. Express (8)

R. J. Zawadzki, B. Cense, Y. Zhang, S. S. Choi, D. T. Miller, and J. S. Werner, “Ultrahigh-resolution optical coherence tomography with monochromatic and chromatic aberration correction,” Opt. Express 16(11), 8126–8143 (2008).
[Crossref] [PubMed]

B. Potsaid, I. Gorczynska, V. J. Srinivasan, Y. Chen, J. Jiang, A. Cable, and J. G. Fujimoto, “Ultrahigh speed spectral / Fourier domain OCT ophthalmic imaging at 70,000 to 312,500 axial scans per second,” Opt. Express 16(19), 15149–15169 (2008).
[Crossref] [PubMed]

I. Grulkowski, M. Gora, M. Szkulmowski, I. Gorczynska, D. Szlag, S. Marcos, A. Kowalczyk, and M. Wojtkowski, “Anterior segment imaging with Spectral OCT system using a high-speed CMOS camera,” Opt. Express 17(6), 4842–4858 (2009).
[Crossref] [PubMed]

B. Cense, W. Gao, J. M. Brown, S. M. Jones, R. S. Jonnal, M. Mujat, B. H. Park, J. F. de Boer, and D. T. Miller, “Retinal imaging with polarization-sensitive optical coherence tomography and adaptive optics,” Opt. Express 17(24), 21634–21651 (2009).
[Crossref] [PubMed]

A. Rollins, S. Yazdanfar, M. Kulkarni, R. Ung-Arunyawee, and J. Izatt, “In vivo video rate optical coherence tomography,” Opt. Express 3(6), 219–229 (1998).
[Crossref] [PubMed]

R. Leitgeb, C. Hitzenberger, and A. Fercher, “Performance of Fourier domain vs. time domain optical coherence tomography,” Opt. Express 11(8), 889–894 (2003).
[Crossref] [PubMed]

M. Choma, M. Sarunic, C. Yang, and J. Izatt, “Sensitivity advantage of swept source and Fourier domain optical coherence tomography,” Opt. Express 11(18), 2183–2189 (2003).
[Crossref] [PubMed]

S. Moon and D. Y. Kim, “Ultra-high-speed optical coherence tomography with a stretched pulse supercontinuum source,” Opt. Express 14(24), 11575–11584 (2006).
[Crossref] [PubMed]

Opt. Lett. (1)

Science (1)

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical coherence tomography,” Science 254(5035), 1178–1181 (1991).
[Crossref] [PubMed]

Other (1)

ANSI Z136, “Safe use of lasers,” Laser Institute of America (2007).

Supplementary Material (3)

» Media 1: AVI (5177 KB)     
» Media 2: AVI (922 KB)     
» Media 3: AVI (1031 KB)     

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Figures (8)

Fig. 1
Fig. 1 Schematic of Indiana MHz AO-OCT system. Key: ACL, achromatizing lens; BS, beam splitter; C, collimator; CMOS, Basler Sprint camera; DG, diffraction grating; DM, deformable mirror; FT, fixation target; GS, glass slide; L, lens; OS, optical switch; PC, polarization controller; PM, planar mirror; P, pupil conjugate plane; R, retinal conjugate plane; S, scanner; SM, spherical mirror; TM, toroidal mirror; WS, wavefront sensor; WV, water vial.
Fig. 2
Fig. 2 Timing diagram showing synchronized operation of the four camera detection channel in Fig. 1. The diagram illustrates the sequence for an exemplary B-scan that sweeps over a +/−V voltage range of the galvanometer scanner during which 40 A-lines are acquired, 10 by each camera, at an acquisition rate of 1 MHz (A-lines/second). The portions of the time trace at which light, camera, and dark exposures occur are labeled.
Fig. 3
Fig. 3 Oscilloscope recordings of MHz AO-OCT control signals (scanners, optical switches, and cameras) and detected light at output ports of the 1 × 4 optical switch (OS) assembly. Horizontal time axes have tick intervals as specified. Vertical voltage axes are of varying scales, e.g., OS and camera control trigger signals are 0–5V TTL signals. CMOS cameras were run in line-trigger mode in which the rising-edge initiated camera exposure. Semi-transparent boxes mark when the camera exposure occurred. Synchronization required time offsets to be applied to the control signals for correction of hardware latencies.
Fig. 4
Fig. 4 Plots compare raw spectra from the spectrometers (A, top) and reconstructed A-lines in normalized logarithmic (log) amplitude (A bottom, B) and normalized linear amplitude (C). Spectra were collected with 30 dB attenuation of the mirror reflection using neutral density filters. CMOS cameras #1, #2, #3, and #4 are color coded per key in spectra plot. COG and FWHM of the four spectrometers are shown in the linear plot (C).
Fig. 5
Fig. 5 Faster image acquisition reduces axial and lateral retinal motion artifacts in the AO-OCT video stream. Retinal image sequence is shown as linear scale projections of the entire volumes in slow scan projection (A). Each sequence is composed of ten successive AO-OCT volumes of a 1.3° × 1.3° patch of retina at 3° nasal to the fovea in subject 2 (400 A-lines/B-scan, 400 B-scans/volume, and 10 volumes/video; totaling 1.6 million A-lines/video). A-lines were acquired using one (250 KHz), two (500 KHz), and four camera (1 MHz) configurations. En face images with characteristic motion artifacts were chosen (B) to illustrate the effects of motion at each speed. None of the en face images in the 1 MHz sequence had a noticeable motion artifact, thus we display the first image of the sequence. All of the en face images at the three speeds can be viewed in Media 1. En face views in the video display all 1.6 million A-lines acquired without cropping or registration. Thus blur along the vertical sides is more apparent at the higher speeds as faster reversal of the galvanometer scanner is needed, especially at 1 MHz. At this highest speed, the fast galvanometer scanner operated at 1.25 KHz (2.5 KHz B-scan rate). This fixed blur pattern can be corrected in post processing [17], but we decided not to in order to show the extent to which the scanner can preserve the symmetric triangular waveform at various speeds. The leftmost two plots (C) show the cross-correlation displacements between successive frames in both projection views, thus depicting inter-frame motion. The rightmost two plots (C) show the cross-correlation coefficient between successive frames, thus depicting intra-frame motion (image warp).
Fig. 6
Fig. 6 MHz AO-OCT images of 3.6° × 3.6° patch of retina at 3° nasal to the fovea of subject 2 acquired with AO focus at photoreceptors (C, E) and at RNFL (D, F). Lateral sampling was 1120 A-lines/Bscan × 1120 B-scans/volume (1μm/pixel). The wide field SLO image (A) shows the location of AO-OCT volumes (B). All AO-OCT images are shown on a linear amplitude scale and without correction of the scanner reversal blur, which appears at the top and bottom of the images (C, D, E, F). Note this blur is smaller than that in the MHz image of Fig. 5 due to the larger FOV. Dynamic range of volumes acquired with focus at photoreceptors and RNFL were 29.6 ± 0.7 dB and 30.3 ± 1.1 dB, respectively.
Fig. 7
Fig. 7 MHz AO-OCT volume sequence of 2.6° × 2.6° patch of retina at 3° nasal to the fovea of subject 2 acquired with AO focus at RNFL. Lateral sampling was 800 A-lines/Bscan × 800 B-scans/volume × 4 Volumes/video (1 μm/pixel, en face). Shown are single unregistered en face frame (A), registered and averaged over 4 en face frames (B), and cross-sectional (B-scan averaged over three successive B-scans) image of RNFL bundles from the location marked by the red line (C). Media 2 combines the registered and unregistered en face videos to facilitate comparison. All AO-OCT images are shown on a linear amplitude scale and without correction of the scanner reversal blur. Dynamic range of volumes was 31.3 ± 0.6 dB.
Fig. 8
Fig. 8 MHz AO-OCT volume sequence of 2.6° × 2.6° patch of retina at 3° nasal to the fovea of subject 1 acquired with AO focus at the photoreceptors. Lateral sampling was 800 A-lines/Bscan × 800 B-scans/volume corresponding to 1μm/pixel. (A) A single unregistered en face frame. (B) Registered and averaged over five en face frames. Also shown is an average of three contiguous B-scans cropped about the photoreceptor and RPE layers (C). B-scan location is marked by the red line. Media 3 shows the registered and unregistered en face videos side by side for comparison. All AO-OCT images are shown on a linear amplitude scale and without correction of the scanner reversal blur. Dynamic range of volumes was 29.5 ± 1.0 dB.

Tables (3)

Tables Icon

Table 1 AO-OCT parameters for retinal imaging.

Tables Icon

Table 2 Subject information.

Tables Icon

Table 3 MHz AO-OCT system performance for the four spectrometers.

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