Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group
Journal Home About Issues in Progress Current Issue All Issues Feature Issues

Enhanced visualization of choroidal vessels using ultrahigh resolution ophthalmic OCT at 1050 nm

B. Považay, K. Bizheva, B. Hermann, A. Unterhuber, H. Sattmann, A.F. Fercher, W. Drexler, C. Schubert, P.K. Ahnelt, M. Mei, R. Holzwarth, W. J. Wadsworth, J.C. Knight, and P. St. J. Russel

Open Access Open Access

Abstract

In this article the ability of ultrahigh resolution ophthalmic optical coherence tomography (OCT) to image small choroidal blood vessels below the highly reflective and absorbing retinal pigment epithelium is demonstrated for the first time. A new light source (λc=1050 nm, Δλ=165 nm, Pout=10 mW), based on a photonic crystal fiber pumped by a compact, self-starting Ti:Al2O3 laser has therefore been developed. Ex-vivo ultrahigh resolution OCT images of freshly excised pig retinas acquired with this light source demonstrate enhanced penetration into the choroid and better visualization of choroidal vessels as compared to tomograms acquired with a state-of-the art Ti:Al2O3 laser (Femtolasers Compact Pro, λc=780 nm, Δλ=160 nm, Pout=400 mW), normally used in clinical studies for in vivo ultrahigh resolution ophthalmic OCT imaging. These results were also compared with retinal tomograms acquired with a novel, spectrally broadened fiber laser (MenloSystems, λc=1350 nm, Δλ=470 nm, Pout=4 mW) permitting even greater penetration in the choroid. Due to high water absorption at longer wavelengths retinal OCT imaging at ~1300 nm may find applications in animal ophthalmic studies. Detection and follow-up of choroidal neovascularization improves early diagnosis of many retinal pathologies, e.g. age-related macular degeneration or diabetic retinopathy and can aid development of novel therapy approaches.

©2003 Optical Society of America

Full Article  |  PDF Article
More Like This
In vivo retinal optical coherence tomography at 1040 nm-enhanced penetration into the choroid

A. Unterhuber, B. Považay, B. Hermann, H. Sattmann, A. Chavez-Pirson, and W. Drexler
Opt. Express 13(9) 3252-3258 (2005)

Three-dimensional visualization of choroidal vessels by using standard and ultra-high resolution scattering optical coherence angiography

Youngjoo Hong, Shuichi Makita, Masahiro Yamanari, Masahiro Miura, Soohyun Kim, Toyohiko Yatagai, and Yoshiaki Yasuno
Opt. Express 15(12) 7538-7550 (2007)

Limiting factors to the OCT axial resolution for in-vivo imaging of human and rodent retina in the 1060nm wavelength range

Sepideh Hariri, Alireza A. Moayed, Aphrodite Dracopoulos, Chulho Hyun, Shelley Boyd, and Kostadinka Bizheva
Opt. Express 17(26) 24304-24316 (2009)

View More...

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (4)
Fig. 1.
Fig. 1. In-vivo ultrahigh resolution OCT image (2700×830 pixels, 5 mm×2 mm) of human retina with areolar atrophy associated with foveomacular dystrophy, acquired with the Ti:Al2O3 light source. Solid arrows indicate intact RPE; dashed arrow indicates RPE with atrophy enabling visualization of choroidal vessels.

Download Full Size | PDF

Fig. 2.
Fig. 2. Output spectra (top): Ti:Al2O3 (blue line), PCF based source (green line) and fiber laser based light source (red line), overlaid with water absorption spectrum (black line). Corresponding fringe patterns produced by interfacing the light sources to the OCT system (bottom).

Download Full Size | PDF

Fig. 3.
Fig. 3. Ex-vivo OCT images of pig retinas, acquired with the Ti:Al2O3 source (top, at ~800 nm, SNR 105 dB, 2000×1000 pixels, 2×1 mm), PCF based source (middle, at ~1050 nm, SNR 98 dB, 2000×1010 pixels, 2×1 mm), and the fiber laser based source (bottom, at ~1350 nm, SNR 95 dB, 2000×888 pixels, 2×1 mm). Red arrows indicate choroidal blood vessels.

Download Full Size | PDF

Fig. 4.
Fig. 4. Ex-vivo OCT image of a pig retina, acquired with the PCF based source at ~1050 nm (2000×1010 pixels, 2 mm×1 mm). The red arrow marks a region in the choroid, where multiple small blood vessels partially filled with coagulated blood, positioned on top of each other are visible. Green arrow depicts a blood vessel on the retinal surface with reduced shadowing because of better penetration at the imaging wavelength.

Download Full Size | PDF

Select as filters
Select Topics Cancel
Top
       
© Copyright 2024 | Optica Publishing Group. All rights reserved, including rights for text and data mining and training of artificial technologies or similar technologies.
Privacy | Terms of Use