Abstract

We report on what we believe is a novel approach to measuring the velocity of red blood cells (RBC’s) at different depths of retinal vessels by use of low-coherence sources. The technique, variable coherence optical Doppler velocimetry (VCODV), performs Doppler shift measurements through autodyne mixing between the light scattered by the RBC’s and by the vessel front wall (reference). Only the light from RBC’s moving at a depth less than half the coherence length (CL) mixes efficiently with the reference. Measurements of the Doppler shifts from RBC’s with sources of four different CL’s in a 152-µm vein of a volunteer confirmed the feasibility of VCODV. This approach has the potential to monitor in vivo retinal RBC velocity gradient at the vessel wall and the velocity profile within the blood vessel in the condition of symmetric blood flow profiles.

© 2000 Optical Society of America

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References

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  1. T. Tanaka, C. E. Riva, I. Ben-Sira, “Blood velocity measurements in human retinal vessels,” Science 186, 830–831 (1974).
    [CrossRef] [PubMed]
  2. C. E. Riva, B. L. Petrig, J. E. Grunwald, “Retinal blood flow,” in Laser Doppler Blood Flowmetry, A. P. Shepherd, P. Å. Öberg, eds. (Kluwer, Boston, 1989), pp. 349–383.
  3. J. E. Grunwald, C. E. Riva, “Retinal blood flow in diabetes,” in Laser Doppler, G. V. Belcaro, U. Hoffmann, A. Bollinger, A. N. Nicolaides, eds. (Med-Orion, London, 1994), pp. 223–247.
  4. G. T. Feke, D. G. Goger, H. Tagawa, F. C. Delori, “Laser Doppler technique for absolute measurement of blood speed in retinal vessels,” IEEE Trans. Biomed. Eng. 34, 673–680 (1987).
    [CrossRef] [PubMed]
  5. A. R. Pries, T. W. Secomb, P. Gaehtgens, “Biophysical aspects of blood flow in the microvasculature,” Cardiovasc. Res. 32, 654–667 (1996).
    [PubMed]
  6. F. Fankhauser, H. Bebie, S. Kwasniewska, “The influence of mechanical forces and flow mechanisms on vessel occlusion,” Lasers Surg. Med. 6, 530–532 (1987).
    [CrossRef] [PubMed]
  7. R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
    [CrossRef] [PubMed]
  8. G. T. Feke, C. E. Riva, “Laser Doppler measurement of blood velocity in human retinal vessels,” J. Opt. Soc. Am. 68, 526–531 (1978).
    [CrossRef] [PubMed]
  9. C. E. Riva, B. L. Petrig, R. D. Shonat, C. J. Pournaras, “Scattering process in LDV from retinal vessels,” Appl. Opt. 28, 1078–1083 (1989).
    [CrossRef] [PubMed]
  10. C. E. Riva, J. E. Grunwald, S. H. Sinclair, K. O’Keefe, “Fundus camera based retinal LDV,” Appl. Opt. 20, 117–120 (1981).
    [CrossRef] [PubMed]
  11. B. L. Petrig, C. E. Riva, “Retinal laser Doppler velocimetry: toward its computer-assisted clinical use,” Appl. Opt. 27, 1126–1134 (1988).
    [CrossRef] [PubMed]
  12. B. L. Petrig, C. E. Riva, “Optic nerve head laser Doppler flowmetry: principle and computer analysis,” in Ocular Blood Flow, Glaucoma Meeting, 1995, H. J. Kaiser, J. Flammer, P. Hendrickson, eds. (Karger, Basel, Switzerland, 1995), pp. 120–127.
  13. C. E. Riva, J. E. Grunwald, B. L. Petrig, “Laser Doppler measurement of retinal blood velocity: validity of the single scattering model,” Appl. Opt. 24, 605–607 (1985).
    [CrossRef] [PubMed]
  14. M. D. Stern, “Laser Doppler velocimetry in blood and multiply scattering fluids: theory,” Appl. Opt. 24, 1968–1986 (1985).
    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
  16. S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography,” in Coherence Domain Optical Methods in Biomedical Science and Clinical Applications III,V. V. Tuchin, J. A. Izatt, eds. Proc. SPIE3598, 177–184 (1999).
  17. S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo human retinal blood flow imaging using color Doppler optical coherence tomography,” in Digest of Conference on Lasers and Electro-Optics (Optical Society of America, Washington, D.C., 1999), Postdeadline paper CPD12.
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
  20. J. A. Izatt, M. D. Kulkarni, S. Yazdanfar, J. K. Barton, A. J. Welch, “In vivo bidirectional color Doppler flow imaging of picoliter blood volumes using optical coherence tomography,” Opt. Lett. 22, 1439–1441 (1997).
    [CrossRef]

1998

R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
[CrossRef] [PubMed]

T. Lindmo, D. J. Smithies, Z. Chen, J. S. Nelson, T. E. Milner, “Accuracy and noise in optical Doppler tomography studied by Monte Carlo simulation,” Phys. Med. Biol. 43, 3045–3064 (1998).
[CrossRef] [PubMed]

1997

1996

A. R. Pries, T. W. Secomb, P. Gaehtgens, “Biophysical aspects of blood flow in the microvasculature,” Cardiovasc. Res. 32, 654–667 (1996).
[PubMed]

1995

1989

1988

1987

F. Fankhauser, H. Bebie, S. Kwasniewska, “The influence of mechanical forces and flow mechanisms on vessel occlusion,” Lasers Surg. Med. 6, 530–532 (1987).
[CrossRef] [PubMed]

G. T. Feke, D. G. Goger, H. Tagawa, F. C. Delori, “Laser Doppler technique for absolute measurement of blood speed in retinal vessels,” IEEE Trans. Biomed. Eng. 34, 673–680 (1987).
[CrossRef] [PubMed]

1985

1981

1978

1974

T. Tanaka, C. E. Riva, I. Ben-Sira, “Blood velocity measurements in human retinal vessels,” Science 186, 830–831 (1974).
[CrossRef] [PubMed]

Alexander, R. W.

R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
[CrossRef] [PubMed]

Barton, J. K.

Bebie, H.

F. Fankhauser, H. Bebie, S. Kwasniewska, “The influence of mechanical forces and flow mechanisms on vessel occlusion,” Lasers Surg. Med. 6, 530–532 (1987).
[CrossRef] [PubMed]

Ben-Sira, I.

T. Tanaka, C. E. Riva, I. Ben-Sira, “Blood velocity measurements in human retinal vessels,” Science 186, 830–831 (1974).
[CrossRef] [PubMed]

Chappell, D. C.

R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
[CrossRef] [PubMed]

Chen, Z.

T. Lindmo, D. J. Smithies, Z. Chen, J. S. Nelson, T. E. Milner, “Accuracy and noise in optical Doppler tomography studied by Monte Carlo simulation,” Phys. Med. Biol. 43, 3045–3064 (1998).
[CrossRef] [PubMed]

Z. Chen, T. E. Milner, S. Srinivas, X. Wang, A. Malekafzali, M. J. C. van Gemert, J. S. Nelson, “Noninvasive imaging of in vivo blood flow velocity using optical Doppler tomography,” Opt. Lett. 22, 1119–1121 (1997).
[CrossRef] [PubMed]

Delori, F. C.

G. T. Feke, D. G. Goger, H. Tagawa, F. C. Delori, “Laser Doppler technique for absolute measurement of blood speed in retinal vessels,” IEEE Trans. Biomed. Eng. 34, 673–680 (1987).
[CrossRef] [PubMed]

Fankhauser, F.

F. Fankhauser, H. Bebie, S. Kwasniewska, “The influence of mechanical forces and flow mechanisms on vessel occlusion,” Lasers Surg. Med. 6, 530–532 (1987).
[CrossRef] [PubMed]

Feke, G. T.

G. T. Feke, D. G. Goger, H. Tagawa, F. C. Delori, “Laser Doppler technique for absolute measurement of blood speed in retinal vessels,” IEEE Trans. Biomed. Eng. 34, 673–680 (1987).
[CrossRef] [PubMed]

G. T. Feke, C. E. Riva, “Laser Doppler measurement of blood velocity in human retinal vessels,” J. Opt. Soc. Am. 68, 526–531 (1978).
[CrossRef] [PubMed]

Gaehtgens, P.

A. R. Pries, T. W. Secomb, P. Gaehtgens, “Biophysical aspects of blood flow in the microvasculature,” Cardiovasc. Res. 32, 654–667 (1996).
[PubMed]

Goger, D. G.

G. T. Feke, D. G. Goger, H. Tagawa, F. C. Delori, “Laser Doppler technique for absolute measurement of blood speed in retinal vessels,” IEEE Trans. Biomed. Eng. 34, 673–680 (1987).
[CrossRef] [PubMed]

Grunwald, J. E.

C. E. Riva, J. E. Grunwald, B. L. Petrig, “Laser Doppler measurement of retinal blood velocity: validity of the single scattering model,” Appl. Opt. 24, 605–607 (1985).
[CrossRef] [PubMed]

C. E. Riva, J. E. Grunwald, S. H. Sinclair, K. O’Keefe, “Fundus camera based retinal LDV,” Appl. Opt. 20, 117–120 (1981).
[CrossRef] [PubMed]

J. E. Grunwald, C. E. Riva, “Retinal blood flow in diabetes,” in Laser Doppler, G. V. Belcaro, U. Hoffmann, A. Bollinger, A. N. Nicolaides, eds. (Med-Orion, London, 1994), pp. 223–247.

C. E. Riva, B. L. Petrig, J. E. Grunwald, “Retinal blood flow,” in Laser Doppler Blood Flowmetry, A. P. Shepherd, P. Å. Öberg, eds. (Kluwer, Boston, 1989), pp. 349–383.

Izatt, J. A.

J. A. Izatt, M. D. Kulkarni, S. Yazdanfar, J. K. Barton, A. J. Welch, “In vivo bidirectional color Doppler flow imaging of picoliter blood volumes using optical coherence tomography,” Opt. Lett. 22, 1439–1441 (1997).
[CrossRef]

S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography,” in Coherence Domain Optical Methods in Biomedical Science and Clinical Applications III,V. V. Tuchin, J. A. Izatt, eds. Proc. SPIE3598, 177–184 (1999).

S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo human retinal blood flow imaging using color Doppler optical coherence tomography,” in Digest of Conference on Lasers and Electro-Optics (Optical Society of America, Washington, D.C., 1999), Postdeadline paper CPD12.

Kulkarni, M. D.

Kwasniewska, S.

F. Fankhauser, H. Bebie, S. Kwasniewska, “The influence of mechanical forces and flow mechanisms on vessel occlusion,” Lasers Surg. Med. 6, 530–532 (1987).
[CrossRef] [PubMed]

Lindmo, T.

T. Lindmo, D. J. Smithies, Z. Chen, J. S. Nelson, T. E. Milner, “Accuracy and noise in optical Doppler tomography studied by Monte Carlo simulation,” Phys. Med. Biol. 43, 3045–3064 (1998).
[CrossRef] [PubMed]

Malekafzali, A.

Medford, R. M.

R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
[CrossRef] [PubMed]

Milner, T. E.

Nelson, J. S.

Nerem, R. M.

R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
[CrossRef] [PubMed]

O’Keefe, K.

Petrig, B. L.

C. E. Riva, B. L. Petrig, R. D. Shonat, C. J. Pournaras, “Scattering process in LDV from retinal vessels,” Appl. Opt. 28, 1078–1083 (1989).
[CrossRef] [PubMed]

B. L. Petrig, C. E. Riva, “Retinal laser Doppler velocimetry: toward its computer-assisted clinical use,” Appl. Opt. 27, 1126–1134 (1988).
[CrossRef] [PubMed]

C. E. Riva, J. E. Grunwald, B. L. Petrig, “Laser Doppler measurement of retinal blood velocity: validity of the single scattering model,” Appl. Opt. 24, 605–607 (1985).
[CrossRef] [PubMed]

B. L. Petrig, C. E. Riva, “Optic nerve head laser Doppler flowmetry: principle and computer analysis,” in Ocular Blood Flow, Glaucoma Meeting, 1995, H. J. Kaiser, J. Flammer, P. Hendrickson, eds. (Karger, Basel, Switzerland, 1995), pp. 120–127.

C. E. Riva, B. L. Petrig, J. E. Grunwald, “Retinal blood flow,” in Laser Doppler Blood Flowmetry, A. P. Shepherd, P. Å. Öberg, eds. (Kluwer, Boston, 1989), pp. 349–383.

Pournaras, C. J.

Pries, A. R.

A. R. Pries, T. W. Secomb, P. Gaehtgens, “Biophysical aspects of blood flow in the microvasculature,” Cardiovasc. Res. 32, 654–667 (1996).
[PubMed]

Riva, C. E.

C. E. Riva, B. L. Petrig, R. D. Shonat, C. J. Pournaras, “Scattering process in LDV from retinal vessels,” Appl. Opt. 28, 1078–1083 (1989).
[CrossRef] [PubMed]

B. L. Petrig, C. E. Riva, “Retinal laser Doppler velocimetry: toward its computer-assisted clinical use,” Appl. Opt. 27, 1126–1134 (1988).
[CrossRef] [PubMed]

C. E. Riva, J. E. Grunwald, B. L. Petrig, “Laser Doppler measurement of retinal blood velocity: validity of the single scattering model,” Appl. Opt. 24, 605–607 (1985).
[CrossRef] [PubMed]

C. E. Riva, J. E. Grunwald, S. H. Sinclair, K. O’Keefe, “Fundus camera based retinal LDV,” Appl. Opt. 20, 117–120 (1981).
[CrossRef] [PubMed]

G. T. Feke, C. E. Riva, “Laser Doppler measurement of blood velocity in human retinal vessels,” J. Opt. Soc. Am. 68, 526–531 (1978).
[CrossRef] [PubMed]

T. Tanaka, C. E. Riva, I. Ben-Sira, “Blood velocity measurements in human retinal vessels,” Science 186, 830–831 (1974).
[CrossRef] [PubMed]

J. E. Grunwald, C. E. Riva, “Retinal blood flow in diabetes,” in Laser Doppler, G. V. Belcaro, U. Hoffmann, A. Bollinger, A. N. Nicolaides, eds. (Med-Orion, London, 1994), pp. 223–247.

B. L. Petrig, C. E. Riva, “Optic nerve head laser Doppler flowmetry: principle and computer analysis,” in Ocular Blood Flow, Glaucoma Meeting, 1995, H. J. Kaiser, J. Flammer, P. Hendrickson, eds. (Karger, Basel, Switzerland, 1995), pp. 120–127.

C. E. Riva, B. L. Petrig, J. E. Grunwald, “Retinal blood flow,” in Laser Doppler Blood Flowmetry, A. P. Shepherd, P. Å. Öberg, eds. (Kluwer, Boston, 1989), pp. 349–383.

Rollins, A. M.

S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography,” in Coherence Domain Optical Methods in Biomedical Science and Clinical Applications III,V. V. Tuchin, J. A. Izatt, eds. Proc. SPIE3598, 177–184 (1999).

S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo human retinal blood flow imaging using color Doppler optical coherence tomography,” in Digest of Conference on Lasers and Electro-Optics (Optical Society of America, Washington, D.C., 1999), Postdeadline paper CPD12.

Secomb, T. W.

A. R. Pries, T. W. Secomb, P. Gaehtgens, “Biophysical aspects of blood flow in the microvasculature,” Cardiovasc. Res. 32, 654–667 (1996).
[PubMed]

Shonat, R. D.

Sinclair, S. H.

Smithies, D. J.

T. Lindmo, D. J. Smithies, Z. Chen, J. S. Nelson, T. E. Milner, “Accuracy and noise in optical Doppler tomography studied by Monte Carlo simulation,” Phys. Med. Biol. 43, 3045–3064 (1998).
[CrossRef] [PubMed]

Srinivas, S.

Stern, M. D.

Tagawa, H.

G. T. Feke, D. G. Goger, H. Tagawa, F. C. Delori, “Laser Doppler technique for absolute measurement of blood speed in retinal vessels,” IEEE Trans. Biomed. Eng. 34, 673–680 (1987).
[CrossRef] [PubMed]

Tanaka, T.

T. Tanaka, C. E. Riva, I. Ben-Sira, “Blood velocity measurements in human retinal vessels,” Science 186, 830–831 (1974).
[CrossRef] [PubMed]

Taylor, W. R.

R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
[CrossRef] [PubMed]

van Gemert, M. J. C.

Varner, S. E.

R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
[CrossRef] [PubMed]

Wang, X.

Wang, X. J.

Welch, A. J.

Yazdanfar, S.

J. A. Izatt, M. D. Kulkarni, S. Yazdanfar, J. K. Barton, A. J. Welch, “In vivo bidirectional color Doppler flow imaging of picoliter blood volumes using optical coherence tomography,” Opt. Lett. 22, 1439–1441 (1997).
[CrossRef]

S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography,” in Coherence Domain Optical Methods in Biomedical Science and Clinical Applications III,V. V. Tuchin, J. A. Izatt, eds. Proc. SPIE3598, 177–184 (1999).

S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo human retinal blood flow imaging using color Doppler optical coherence tomography,” in Digest of Conference on Lasers and Electro-Optics (Optical Society of America, Washington, D.C., 1999), Postdeadline paper CPD12.

Am. J. Med. Sci.

R. M. Nerem, R. W. Alexander, D. C. Chappell, R. M. Medford, S. E. Varner, W. R. Taylor, “The study of the influence of flow on vascular endothelial biology,” Am. J. Med. Sci. 316, 169–175 (1998).
[CrossRef] [PubMed]

Appl. Opt.

Cardiovasc. Res.

A. R. Pries, T. W. Secomb, P. Gaehtgens, “Biophysical aspects of blood flow in the microvasculature,” Cardiovasc. Res. 32, 654–667 (1996).
[PubMed]

IEEE Trans. Biomed. Eng.

G. T. Feke, D. G. Goger, H. Tagawa, F. C. Delori, “Laser Doppler technique for absolute measurement of blood speed in retinal vessels,” IEEE Trans. Biomed. Eng. 34, 673–680 (1987).
[CrossRef] [PubMed]

J. Opt. Soc. Am.

Lasers Surg. Med.

F. Fankhauser, H. Bebie, S. Kwasniewska, “The influence of mechanical forces and flow mechanisms on vessel occlusion,” Lasers Surg. Med. 6, 530–532 (1987).
[CrossRef] [PubMed]

Opt. Lett.

Phys. Med. Biol.

T. Lindmo, D. J. Smithies, Z. Chen, J. S. Nelson, T. E. Milner, “Accuracy and noise in optical Doppler tomography studied by Monte Carlo simulation,” Phys. Med. Biol. 43, 3045–3064 (1998).
[CrossRef] [PubMed]

Science

T. Tanaka, C. E. Riva, I. Ben-Sira, “Blood velocity measurements in human retinal vessels,” Science 186, 830–831 (1974).
[CrossRef] [PubMed]

Other

C. E. Riva, B. L. Petrig, J. E. Grunwald, “Retinal blood flow,” in Laser Doppler Blood Flowmetry, A. P. Shepherd, P. Å. Öberg, eds. (Kluwer, Boston, 1989), pp. 349–383.

J. E. Grunwald, C. E. Riva, “Retinal blood flow in diabetes,” in Laser Doppler, G. V. Belcaro, U. Hoffmann, A. Bollinger, A. N. Nicolaides, eds. (Med-Orion, London, 1994), pp. 223–247.

S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography,” in Coherence Domain Optical Methods in Biomedical Science and Clinical Applications III,V. V. Tuchin, J. A. Izatt, eds. Proc. SPIE3598, 177–184 (1999).

S. Yazdanfar, A. M. Rollins, J. A. Izatt, “In vivo human retinal blood flow imaging using color Doppler optical coherence tomography,” in Digest of Conference on Lasers and Electro-Optics (Optical Society of America, Washington, D.C., 1999), Postdeadline paper CPD12.

B. L. Petrig, C. E. Riva, “Optic nerve head laser Doppler flowmetry: principle and computer analysis,” in Ocular Blood Flow, Glaucoma Meeting, 1995, H. J. Kaiser, J. Flammer, P. Hendrickson, eds. (Karger, Basel, Switzerland, 1995), pp. 120–127.

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Figures (5)

Fig. 1
Fig. 1

VCODV principle. A beam aimed at a retinal vessel is scattered by the moving RBC’s and the nonmoving front vessel wall (R). Because this nonshifted light is much more intense than the light scattered by the RBC’s, a reference beam is thus provided for the autodyne detection of the DSPS by interference between the two beams at the detector surface. For the coherence function shown (CL), Doppler shifts are detected only for RBC’s moving close to the anterior vessel wall (A). Since the optical path difference between light scattered by RBC’s moving farther away from the front wall (B) and the reference beam is longer than CL, no interference occurs, and therefore no Doppler shift is detected from the RBC’s outside a half CL.

Fig. 2
Fig. 2

DSPS (arbitrary units, a.u.) obtained from a 152-µm retinal vein of a human volunteer with a source with (a) CL = 21 µm and (b) CL = 32 µm. The rectangular fit is also shown (acquisition time, 50 ms).

Fig. 3
Fig. 3

Numerically determined DSPS (arbitrary units, a.u.) obtained from a 152-µm vein with CL’s equal to 14, 21, and 32 µm (see text for details of the calculation).

Fig. 4
Fig. 4

f cutoff obtained from the retinal vein for the different CL’s. Circles, each data point is the mean (plus or minus) standard deviation) of at least 235 DSPS. The confidence intervals of the means are within the circles. Triangles, each data point is the f cutoff obtained with the least-square rectangular fit applied to the numerically determined DSPS (see text).

Fig. 5
Fig. 5

Variation of f cutoff during two cardiac cycles in a retinal vein close to the optic disk. CL’s were 21 µm and high coherence (HC).

Tables (1)

Tables Icon

Table 1 Characteristics of Light Sources Used in the VCODV Experiments

Metrics