A Major Review of Optical Coherence Tomography Angiography

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Published: xv April 2015

A review of optical coherence tomography angiography (OCTA)

International Journal of Retina and Vitreous volume ane, Article number:5 (2015) Cite this article

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Abstract

Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging technique that generates volumetric angiography images in a matter of seconds. This is a nascent technology with a potential wide applicability for retinal vascular disease. At nowadays, level i evidence of the technology'southward clinical applications doesn't exist. In this paper, nosotros introduce the engineering science, review the available English linguistic communication publications regarding OCTA, and compare information technology with the current angiographic gold standards, fluorescein angiography (FA) and indocyanine green angiography (ICGA). Finally we summarize its potential application to retinal vascular diseases. OCTA is quick and non-invasive, and provides volumetric data with the clinical capability of specifically localizing and delineating pathology along with the power to show both structural and blood flow data in tandem. Its current limitations include a relatively modest field of view, inability to prove leakage, and proclivity for paradigm antiquity due to patient movement/blinking. Published studies hint at OCTA'south potential efficacy in the evaluation of common ophthalmologic diseases such age related macular degeneration (AMD), diabetic retinopathy, avenue and vein occlusions, and glaucoma. OCTA tin discover changes in choroidal blood vessel menstruation and tin elucidate the presence of choroidal neovascularization (CNV) in a diversity of weather but specially in AMD. It provides a highly detailed view of the retinal vasculature, which allows for authentic delineation of the foveal avascular zone (FAZ) in diabetic eyes and detection of subtle microvascular abnormalities in diabetic and vascular occlusive eyes. Optic disc perfusion in glaucomatous eyes is notable every bit well on OCTA. Further studies are needed to more definitively determine OCTA's utility in the clinical setting and to establish if this technology may offer a non-invasive option of visualizing the retinal vasculature in particular.

Introduction

Optical coherence tomography angiography (OCTA) is a new non-invasive imaging technique that employs motility contrast imaging to high-resolution volumetric blood flow information generating angiographic images in a matter of seconds. OCTA compares the decorrelation bespeak (differences in the backscattered OCT signal intensity or aamplitude) between sequential October b-scans taken at precisely the same cross-section in gild to construct a map of blood flow. Axial bulk motility from patient motion is eliminated and so sites of motion between repeated OCT b-scans represent strictly erythrocyte movement in retinal blood vessels [1-4].

OCTA requires higher imaging speeds than most currently available OCT systems can provide in order to obtain a densely sampled volume. Conventional October device scanning speeds would effect in as well much trade-off between decreased field of view, lower image quality, and greatly increased scanning time.

Comparison OCTA with FA and ICGA

Fluorescein angiography (FA) and indocyanine green angiography (ICGA) are both invasive test that require intravenous assistants of dye and imaging up to 10–30 minutes [v-9]. They provide ii-dimensional image sets that permit for dynamic visualization of claret flow with a wide field of view. Therefore, patterns of dye leakage, pooling, and staining can exist appreciated and are well-documented in the literature [10]. FA remains the golden standard for the detection of choroidal neovascularization (CNV), also as retinal neovascularization such every bit neovascularization of the disc (NVD) and neovascularization elsewhere (NVE) [11-thirteen]. However, retinal pathology can exist obscured by this leakage also as hemorrhage or media opacities, and localization of the depth of the lesion and size delineation of neovascularization can be hard due to dye leakage and poor stereopsis, and because the imaging modalities are not depth resolved. As a result, segmentation of different layers is not routinely possible with FA or ICGA. Therefore, identification of the axial location of pathology requires an understanding of patterns of blockage and leakage [10]. For example, differentiation betwixt blazon ane CNV, which is found between the retinal paint epithelium (RPE) and Bruch'due south membrane, and type 2 CNV, which is constitute in the subretinal infinite above the RPE, requires understanding that the RPE blocks underlying fluorescence so type 1 CNV requires a larger amount of dye to accumulate before hyperfluorescence is credible [xiv].

FA and ICGA have other drawbacks that tin can limit their widespread use. Since they are invasive, relatively expensive, and time-consuming, they are non ideal techniques to use on a regular footing in a busy clinical setting. Although considered safe, the dyes pose risks ranging from nausea to allergic reactions, including anaphylaxis in rare instances. Aside from allergic reactions of which the likelihood increases with frequency of use, indocyanine green dye is contraindicated in pregnancy and kidney affliction [15-17]. For the evaluation of patients requiring frequent follow-up exams or of those that may not tolerate injection of intravenous dye, a rapid non-invasive technique to visualize retinal and choroidal vessels would be beneficial.

OCTA in comparing is a non-invasive technique that acquires volumetric angiographic information without the use of dye. Each 3-dimensional scan set takes approximately six seconds to obtain. The en-face images (OCT angiograms) can so be scrolled outward from the internal limiting membrane (ILM) to the choroid to visualize the individual vascular plexus and segment the inner retina, outer retina, choriocapillaris, or other area of involvement. The en-face acquisition areas currently range from 2 × two mm to 12 × 12 mm with the scan quality greatly decreased with a widened field of view since the same number of OCT b-scans is used for all scanning areas. The 12 x 12 mm browse is only bachelor on inquiry prototypes. The 3 × three mm Oct angiograms appear to be higher resolution than the currently available FA/ICGA images, and a study by Matsunaga et al. deduced that they were at least equivalent in showing important vascular particular [18]. Utilize of the montage technique allows for a larger field of view much like FA/ICGA while maintaining this improved resolution (Effigy 1; de Carlo TE et al., unpublished information in review). Carl Zeiss, Inc (Carl Zeiss Meditec, Dublin, CA) is developing an automated broad-field montage software, which employs movement tracking to rail the optics and stitch images together.

OCTA provides menstruum information at a stock-still point in time. Although leakage is not appreciable, exact delineation and size measurements tin be performed for pathology such as CNV (de Carlo TE et al., unpublished data in review) [19]. This is particularly useful for identification of blazon ane CNV where localization is inferential and therefore may exist inaccurate with FA/ICGA. Retinal blood flow on OCTA tin exist obscured by hemorrhage as this decreases the ability of low-cal to penetrate into the deeper layers of the eye.

OCTA provides both structural and functional (i.e. claret catamenia) information in tandem. The "respective" OCT b-scans can be co-registered with the simultaneous Oct angiograms so the operator is able to scroll through the OCT angiogram like a cube browse. As a result, the precise location of pathology can be viewed on the corresponding OCT b-scans. The axial resolution of the corresponding Oct b-scans are lower quality than the typical highly-sampled line scans and are similar to the resolution of individual Oct b-scans inside a volumetric cube scan. Both the retinal and the choroidal microvasculature can be visualized using OCTA while FA is used for seeing the retinal vessels and ICGA is more platonic for imaging the choroid.

Using the present technology, OCTA is more than decumbent to artifact than FA or ICGA. The larger retinal vessels cause a "ghost image" referred to as a shadow antiquity, when segmenting deeper layers, particularly the outer retina. This can brand it more difficult to appreciate the presence of abnormal vasculature in the deeper layers. Because OCTA uses the principle that movement in the back of the eye represents blood menstruation, it is prone to move artifact. White lines (representing decorrelation signal over the entire b-scan) announced in areas of bulk patient move such as when the patient loses fixation or moves. Conversely, blinks appear as a blackness line beyond the OCT angiogram because the Oct signal is blocked from reaching the retina and the software, therefore, detects no movement. Although erythrocytes should exist the simply moving object in the retina, some non-vascular structures such as fine tissue may also cause a decorrelation signal, especially if the patient is moving. For instance, the edges of a retinal pigment epithelial detachment (RPED) often testify up on OCTA as white dissonance antiquity in cases of increased patient motion. Information technology is postulated that because the RPE is a fine structure, in areas of disruption such as a RPED, information technology can presumably move and therefore be detected on the OCT angiogram.

On the other hand, OCTA can besides miss areas of dull blood flow such as in microaneurysms or fibrotic CNV. Since OCTA relies on change betwixt consecutive b-scans, it will notice period only in a higher place a minimum threshold, the slowest detectable menstruum, which is determined by the time between the ii sequential Oct b-scans. Lesions that accept flow beneath the slowest detectable flow would therefore not be visualized using this imaging technique. Increasing the fourth dimension between consecutive Oct b-scans could let for increased flow detection but would offer a merchandise-off due to increased motion artifact. One of the advantages of a higher speed organisation is that multiple volumetric sets tin exist obtained at each cantankerous-section and so the threshold tin be altered later by selecting dissimilar fourth dimension frames between the October b-scans to decide the optimal prototype quality. Therefore if a low-catamenia vessel is undetectable by using the first and 2d Oct b-scans at a given cantankerous section, the image may be processed using the first and 3rd Oct b-scans to increment the time betwixt the Oct b-scans thereby decreasing the minimum threshold.

A couple of publications have qualitatively compared OCTA with FA. Spaide et al. described the peripapillary retinal vascular layers in 12 normal eyes, finding that OCTA provided improved visualization of all the vascular layers including the radial peripapillary and deep capillary networks that were non well-distinguished on FA [3]. OCTA imaging of the perifoveal region was reported by Matsunaga et al., demonstrating that the ability to see the normal retinal vasculature was equivalent to that of FA [18].

Review

OCTA of normal optics

The most widely available image OCTA system is the AngioVue software of the RTVue XR Avanti spectral-domain Oct (SD-October) (Optovue, Inc, Fremont, CA), which uses a split up-spectrum aamplitude decorrelation angiography (SSADA) algorithm. The device obtains volumetric scans of 304 × 304 A-scans at seventy,000 A-scans per second in approximately iii.0 seconds. The software offers the selection of two × 2 mm, 3 × 3 mm, 6 × 6 mm, and viii × viii mm October angiograms (Figure 2A-C) and automatic segmentation of these full-thickness retinal scans into the "superficial" and "deep" inner retinal vascular plexuses, outer retina, and choriocapillaris (Figure 2E-H). The OCT angiogram segmentation of the superficial inner retina contains a projection of the vasculature in the retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) (Effigy 2E). The deep inner retina OCT angiogram partition shows a composite of the vascular plexuses at the border of the inner plexiform layer (IPL) and inner nuclear layer (INL) and the border of the INL and outer plexiform layer (OPL) (Figure 2F).

The OCTA prototype with the fastest acquisition rate was developed by the Massachusetts Institute of Technology using a swept-source OCT (SS-Oct) device (Department of Electrical Engineering and Computer science and Inquiry Laboratory of Electronics, Massachussetts Institute of Engineering science, Cambridge, MA). This ultra-high speed prototype employs a vertical cavity surface emitting laser (VCSEL) operating at 1060 nm wavelength which allows increased low-cal penetration into pigmented tissues and improved choroidal claret flow visualization compared to the lite source used in SD-Oct. The SS-OCTA system obtains scans of 500 × 500 A-scans at 400,000 A-scans per second in approximately 3.eight seconds. This ultra-high speed allows for imaging of wider fields of view. The prototype can be manipulated to obtain OCT angiograms up to 12 × 12 mm, nevertheless, it is most usually used to create 3 × iii mm and half-dozen × 6 mm Oct angiograms of dandy detail (Figure 3A-B). Full-thickness scans are manually segmented into the superficial (plexus at the RNFL), intermediate (plexus at the GCL), and deep (plexuses at IPL/INL and INL/OPL borders) inner retinal vascular plexuses, outer retina, choriocapillaris, and choroidal layers (Effigy 3D-F). Using this OCTA system, the choriocapillaris and choroidal vessels were described in normal eyes by Choi et al [ii].

OCTA of dry (Not-Neovascular) AMD

Dry age-related macular degeneration (AMD) is characterized by drusen, pigmentary changes, and photoreceptor and RPE loss, called geographic cloudburst (GA). Decreased foveolar choroidal claret menstruum is associated with AMD and increased drusen extent, and it has been hypothesized that the choroidal blood menses may predict disease progression [14]. Choi et al. (unpublished data, presented in part at the Association for Enquiry in Vision and Ophthalmology annual coming together, May 2014, Orlando, Florida) demonstrated OCTA findings in dry out AMD. Areas of impaired choriocapillaris menstruation typically extended beyond the borders of the GA. Eyes with dry out AMD were shown to have a generalized subtract in choriocapillaris density, which was sometimes associated with drusen. Figures 4 and v demonstrate discrete areas of decreased point at the choriocapillaris level below many but not all drusen in 3 eyes. These areas of alteration did non appear to be due to shadowing (from material in the drusen), and some choroidal vessels were appreciated below these areas. However, further studies would be necessary to determine if the choriocapillaris changes associated with the drusen are true areas of catamenia damage. Choriocapillaris flow alterations are besides shown in two eyes along the border of GA in Figure half-dozen.

OCTA of moisture (Neovascular) AMD

Several publications concerning OCTA of eyes with moisture AMD appear in the literature. In July 2014 Jia et al. get-go described the power of a prototype SS-OCTA system to visualize and quantify CNV that had been seen on FA in five eyes [19]. And so in November 2014, Moult and Choi et al. described CNV in 16 of 19 eyes with neovascularization, noting that the majority of these eyes (14/16, 88%) also demonstrated choriocapillaris alteration surrounding the CNV [20]. De Carlo et al. described qualitative and quantitative characteristics of CNV in 48 eyes [21]. The group determined sensitivity and specificity of the image AngioVue software, using FA as the ground truth, to be 50% (four/8) and 91% (twenty/22) respectively, hypothesizing that the low sensitivity was due to small sample size and blockage from big amounts of retinal hemorrhage in some patients. Figures vii and eight illustrate three examples of CNV, including i blazon 3 CNV (retinal angiomatous proliferation, RAP), on OCTA confirmed with FA/ICGA, using the Angiovue OCTA software of the RTVue XR Avanti (Optovue, Inc., Fremont, CA). Figure nine shows 2 OCTA examples of CNV, 1 of which was treatment naïve, using the SS-Oct prototype (Department of Electric Engineering and Informatics and Inquiry Laboratory of Electronics, Massachussetts Insitute of Technology, Cambridge, MA).

OCTA of diabetes

There are few published papers equally of early on 2015 on OCTA of diabetic retinopathy. Choi et al. (unpublished data) demonstrated that OCTA of diabetic eyes ranging from no retinopathy to proliferative diabetic retinopathy (PDR) demonstrated choriocapillaris abnormalities and/or retinal microvascular abnormalities such every bit microaneurysms, vascular remodeling adjacent to the foveal avascular zone (FAZ), enlarged FAZ, and capillary tortuosity and dilation. OCTA and FA were compared in unpublished data past Salz et al. The group supported the utility of OCTA in evaluating FAZ and the perifoveal intercapillary surface area, showing that they were sequentially enlarged in each stages of diabetic retinopathy (normal eyes to PDR). The data showed that OCTA visualized the majority merely not all of the microaneurysms visualized past FA probable because OCTA is limited by the principle of slowest detectable flow. Nonetheless, OCTA was able to appreciate some microaneurysms that were non detected past FA. OCTA as well successfully detected other abnormalities that were not evident on FA such as areas of retinal non-perfusion, reduced capillary density, and increased vessel tortuosity. de Carlo et al. (unpublished data in review) described a wide-field OCTA montage of an centre with newly proliferative diabetic retinopathy. The wide-field montage OCTA prototype also successfully allowed visualization of an enlarged FAZ, perifoveal intercapillary area, and multiple microaneurysms. It also provided a larger field of view allowing more peripheral detection of microvascular changes, early NVE, and areas of capillary not-perfusion including areas too small to visualize on FA.

Figure ten shows an enlarged FAZ on OCTA and compares OCTA and FA in the identification of microaneurysms in two eyes with not-proliferative diabetic retinopathy (NPDR). Capillary non-perfusion and other retinal microvascular abnormalities are demonstrated in Effigy 11. OCTA examples of NVD and NVE in PDR eyes are shown in Effigy 12.

OCTA of artery and vein occlusion

Retinal vascular occlusions have yet to be described in the literature using OCTA as an imaging modality. However, preliminary work at the New England Eye Center of Boston, MA shows that OCTA may be useful for evaluating these diseases. Unpublished data in review by de Carlo et al. described a case of co-operative retinal vein apoplexy (BRVO) using a wide-field montage technique. The OCTA showed a big wedge-shaped area of capillary non-perfusion in the inferotemporal macula with articulate delineation of the purlieus of ischemia, and vascular abnormalities such equally microaneurysms, telangiectasis, and anastamoses.

Figure thirteen shows OCT angiograms of an astute branch retinal avenue occlusion (BRAO) and a subacute primal retinal artery occlusion (CRAO). The BRAO demonstrates wedge-shaped areas of capillary non-perfusion that correlate to areas of abnormalities on the retinal thickness map. This illustrates the potential use of OCTA in pinpointing areas of ischemia and edema. The CRAO shows diffuse capillary non-perfusion in areas supplied by the central retinal avenue as seen on the same-day FA. Menses is withal seen in the major retinal vessels. Around the optic disc, there is an absence of blood menstruum in the superficial disc vasculature supplied past the central retinal artery just the lamina cribosa claret flow remains intact. Every bit OCTA provides a snapshot in fourth dimension, information technology does not demonstrate delayed arteriovenous transit fourth dimension as FA does.

A instance of BRVO and a case of central retinal vein occlusion (CRVO) are illustrated in Figure xiv. OCTA of the BRVO shows capillary not-perfusion superotemporally forth the superior arcade extending into the FAZ, and telangiectatic vessels, capillary loops, and possible microaneurysms at the edge of the ischemic areas. The OCTA of the chronic CRVO demonstrates diffuse capillary not-perfusion continuous with the FAZ and telangiectatic vessels.

OCTA of glaucoma

OCTA is a useful tool for evaluating optic disc perfusion in glaucomatous eyes. The normally dense peripapillary microvascular network is attenuated in both the superficial disc vasculature and the deeper lamina cribosa. Averaging the decorrelation signal in Oct angiograms approximates the expanse of microvasculature and allows the user to calculate the flow index, which is decreased in eyes with glaucoma. The flow index has been shown to have both a very high sensitivity and specificity in differentiating glaucomatous eyes from normal eyes [22,23].

Conclusions

OCTA is a new technology that has great potential for utilize in the clinical setting. Compared with FA and ICGA, the current retinal angiographic gold standards, OCTA advantages are that information technology is non-invasive, acquires volumetric scans that can be segmented to specific depths, uses motion contrast instead of intravenous dye, tin can exist obtained within seconds, provides authentic size and localization information, visualizes both the retinal and choroidal vasculature, and shows structural and blood flow information in tandem. Disadvantages of OCTA are its limited field of view, inability to view leakage, increased potential for artifacts (blinks, movement, vessel ghosting), and disability to notice blood period below the slowest detectable flow.

OCTA has been shown to exist a useful imaging modality for the evaluation of mutual ophthalmologic diseases such AMD, diabetic retinopathy, artery and vein occlusions, and glaucoma. In some cases OCTA has fifty-fifty been shown to notice pathology not seen on FA. In the future, faster scanning speeds would be crucial to obtain larger fields of view with higher resolution. More studies are needed to decide OCTA's utility in the clinical setting and to decide if this technology may offer a non-invasive option of visualizing the retinal vasculature in particular.

Abbreviations

AMD:: Historic period-related macular degeneration
BRAO:: Branch retinal artery occlusion
BRVO:: Branch retinal vein occlusions
CRAO:: Cardinal retinal artery apoplexy
CRVO:: Cardinal retinal vein occlusions
CSCR:: Central serous chorioretinopathy
CNV:: Choroidal neovascularization
FA:: Fluorescein angiography
FAZ:: Foveal avascular zone
GCL:: Ganglion jail cell layer
GA:: Geographic atrophy
ICGA:: Indocyanine green angiography
INL:: Inner nuclear layer
IPL:: Inner plexiform layer
ILM:: Internal limiting membrane
NVE:: Neovascularization elsewhere
NVD:: Neovascularization of the disc
NPDR:: Non-proliferative diabetic retinopathy
OCT:: Optical coherence tomography
OCTA:: Optical coherence tomography angiography
OPL:: Outer plexiform layer
RPED:: Retinal pigment epithelial disengagement
PCV:: Polypoidal choroidal vasculopathy
PDR:: Proliferative diabetic retinopathy
RAP:: Retinal angiomatous proliferation
RNFL:: Retinal nerve fiber layer
RPE:: Retinal pigment epithelium
SD-October:: Spectral domain optical coherence tomography
SSADA:: Split-spectrum amplitude decorrelation angiography
SS-OCT:: Swept source optical coherence tomography
VCSEL:: Vertical cavity surface emitting laser

References

Kim DY, Fingler J, Zawadzki RJ, Park SS, Morse LS, Schwartz DM, et al. Optical Imaging of the chorioretinal vasculature in the living human center. Proc Natl Acad Sci. 2013;110:14354–9.

Article PubMed Central CAS PubMed Google Scholar
Choi Westward, Mohler KJ, Potsaid B, Lu CD, Liu JJ, Jayaraman 5, et al. Choriocapillaris and Choroidal Microvasculature Imaging with Ultrahigh Speed OCT Angiography. Plos Ane. 2013;8:e81499.

Article PubMed Key PubMed Google Scholar
Schwartz DM, Fingler J, Kim DY, Zawadzki RJ, Morse LS, Park SS, et al. Stage-variance optical coherence tomography: a technique for noninvasive angiography. Ophthalmology. 2014;121:180–vii.

Article PubMed Primal PubMed Google Scholar
Spaide RF, Klancnik JM, Cooney MJ. Retinal Vascular Layers Imaged by Fluorescein Angiography and Optical Coherence Tomography Angiography. JAMA Ophthalmol. 2014; E1-6. doi:x.1001/jamaophthalmol.2014.3616.
Novotny 60 minutes, Alvis DL. A method of photographing fluorescence in circulating claret in the human retina. Circulation. 1961;24:82–six.

Article CAS PubMed Google Scholar
Novotny HR, Alvis D. A method of photographing fluorescence in circulating blood of the human being center. Tech Doc Rep SAMTDR USAF Sch Aerosp Med. 1960;sixty–82:ane–iv.

PubMed Google Scholar
Kogure One thousand, Choromokos Eastward. Infrared absorption angiography. J Appl Physiol. 1969;26(one):154–seven.

CAS PubMed Google Scholar
Yannuzzi LA, Slakter JS, Sorenson JA, Guyer DR, Orlock DA. Digital indocyanine green videoangiography and choroidal neovascularization. Retina. 1992;12(iii):191–223.

Article CAS PubMed Google Scholar
Staurenghi G, Bottoni F, Giani A. Clinical Applications of Diagnostic Indocyanine Green Angiography. In: Ryan SJ, Sadda SR, Hinton DR, editors. Retina. London: Elsevier Saunders; 2013. p. 51–81.

Chapter Google Scholar
Johnson RN, Fu Ad, McDonald HR, Jumper Yard, Ai E, Cunningham ET, et al. Fluorescein Angiography: Basic Principles and Interpretation. In: Ryan SJ, Sadda SR, Hinton DR, editors. Retina. London: Elsevier Saunders; 2013. p. 2–50.

Affiliate Google Scholar
Do DV, Gower EW, Cassard SD, Boyer D, Bressler NM, Bressler SB, et al. Detection of New-Onset Choroidal Neovascularization Using Optical Coherence Tomography: the AMD DOC Report. Ophthalmology. 2012;119:771–8.

Commodity PubMed Google Scholar
Kotsolis AI, Killian FA, Ladas ID, Yannuzzi LA. Fluorescein Angiography and Optical Coherence Tomography Concordance for Choroidal Neovascularization in Multifocal Choroiditis. Br J Ophthalmol. 2010;94:1506–8.

Article PubMed Google Scholar
Exercise DV. Detection of New-Onset Choroidal Neovascularization. Curr Opin Ophthalmol. 2013;24:224–vii.

Article Google Scholar
Bressler NM, Bressler SB. Neovascular (Exudative or "Wet") Age-Related Macular Degeneration. In: Ryan SJ, Sadda SR, Hinton DR, editors. Retina. London: Elsevier Saunders; 2013. p. 1183–212.

Chapter Google Scholar
Yuan A, Kaiser PK. Branch Vein Occlusion. In: Ryan SJ, editor. Retina. fifth ed. Mainland china: Saunders; 2013. p. 1029–38.

Chapter Google Scholar
Kwiterovich KA, Maquire MG, Potato RP, Schachat AP, Bressler NM, Bressler SB, et al. Frequency of adverse systemic reactions after fluorescein angiography. Results of a prospective study. Ophthalmology. 1991;98:1139–42.

Article CAS PubMed Google Scholar
Lopez-Saez MP, Ordoqui Eastward, Tornero P, Baeza A, Sainza T, Zubeldia JM, et al. Fluorescein-Induced Allergic Reaction. Ann Allergy Asthma Immunol. 1998;81:428–xxx.

Commodity CAS PubMed Google Scholar
Matsunaga D, Puliafito CA, Kashani AH. October Angiography in Good for you Human Subjects. Ophthalmic Surg Lasers Imaging Retina. 2014;45(six):510–5.

Commodity PubMed Google Scholar
Jia Y, Bailey ST, Wilson DJ, Tan O, Klein ML, Flaxel CJ, et al. Quantitative Optical Coherence Tomography Angiography of Choroidal Neovascularization in Age-Related Macular Degeneration. Ophthalmology. 2014;121:1435–44.

Article PubMed Google Scholar
Moult E, Choi West, Waheed NK, Adhi M, Lee B, Lu CD, et al. Ultrahigh-Speed Swept-Source Oct Angiography in Exudative AMD. Ophthalmic Surg Lasers Imaging Retina. 2014;45(half dozen):496–505.

Article PubMed Google Scholar
de Carlo TE, Bonini Filho MA, Chin AT, Adhi K, Ferrara D, Baumal CR, et al. Spectral Domain Optical Coherence Tomography Angiography (OCTA) of Choroidal Neovascularization. Ophthalmology. In press.
Jia Y, Morrison JC, Tokayer J, Tran O, Lombardi Fifty, Baumann B, et al. Quantitative OCT Angiography of Optic Nerve Caput Blood Flow. Biomed Opt Express. 2012;3(12):3127–37.

Article PubMed Central PubMed Google Scholar
Jia Y, Wei Eastward, Wang X, Zhang X, Morrison JC, Parikh Chiliad, et al. Optical Coherence Tomography Angiography of Optic Disc Perfusion in Glaucoma. Ophthalmology. 2014;seven(121):1322–32.

Commodity Google Scholar

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Acknowledgements

The authors gratefully acknowledge Dr. James G. Fujimoto, Eric Moult, Chen Lu, Jonathan Liu, Alex Cable, and Vijaysekhar Jayaraman for developing the prototype SS-OCTA system and processing the images used in iii of our figures. Additionally we gratefully acknowledge Dr. Caroline R. Baumal and Dr. Andre J. Witkin who each provided ane patient case included in this review.

Author information

Affiliations

New England Eye Eye and Tufts Medical Heart, Tufts University, 260 Tremont Street, Biewend Building, 9 - 11th Floor, Boston, MA, 02116, The states

Talisa Due east de Carlo, Nadia Thou Waheed & Jay S Duker
Department of Electric Engineering science and Informatics, and Research Laboratory of Electronics, Massachusetts Establish of Technology, Cambridge, MA, 02139, USA

Talisa E de Carlo
Department of Ophthalmology, Federal University of São Paulo, Escola Paulista de Medicina, São Paulo, Brazil

Andre Romano
Retina Service, Neovista Eye Center, Americana, Brazil

Andre Romano

Corresponding author

Correspondence to Jay S Duker.

Additional information

Competing interests

Fiscal Support: This work was supported in office past a Research to Prevent Blindness Unrestricted grant to the New England Middle Center/Section of Ophthalmology, Tufts University School of Medicine, and the Massachusetts Lions Clubs.

Financial Disclosure: Jay S. Duker is a consultant for and receives inquiry support from Carl Zeiss Meditech, Inc. and OptoVue, Inc.; André Romano is a consultant for and receives research support from OptoVue, Inc.

Authors' contributions

TED drafted the article and created the figures. AR, NKW, and JSD each contributed to the formulation and pattern of the article and critically revised the manuscript. All authors read and canonical the concluding manuscript.

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de Carlo, T.E., Romano, A., Waheed, N.K. et al. A review of optical coherence tomography angiography (OCTA). Int J Retin Vitr one, 5 (2015). https://doi.org/10.1186/s40942-015-0005-8

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Received: 06 February 2015
Accepted: ten March 2015
Published: 15 April 2015
DOI : https://doi.org/10.1186/s40942-015-0005-8

Keywords

Age-related macular degeneration
Diabetic retinopathy
Fluorescein angiography
Glaucoma
Indocyanine angiography
Optical coherence tomography angiography
Optic disc
Retina
Retinal vessel occlusion

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