Coherence Angiography Research Articles

In vivo human retinal swept source optical coherence tomography and angiography at 830\xa0nm with a CMOS compatible photonic integrated circuit

Photonic integrated circuits (PIC) provide promising functionalities to significantly reduce the size and costs of optical coherence tomography (OCT) systems. This paper presents an imaging platform operating at a center wavelength of 830 nm for ophthalmic application using PIC-based swept source OCT. An on-chip Mach–Zehnder interferometer (MZI) configuration, which comprises an input power splitter, polarization beam splitters in the sample and the reference arm, and a 50/50 coupler for signal interference represents the core element of the system with a footprint of only (12 times 5);{text {mm}}^2. The system achieves 94 dB imaging sensitivity with 750 upmu W on the sample, 50 kHz imaging speed and 5.5 upmu m axial resolution (in soft tissue). With this setup, in vivo human retinal imaging of healthy subjects was performed producing B-scans, three-dimensional renderings as well as OCT angiography. These promising results are significant prerequisites for further integration of optical and electronic building blocks on a single swept source-OCT PIC.

Comparison of fundus changes following silicone oil and sterilized air tamponade for macular-on retinal detachment patients

BackgroundTo investigate different tamponade effects of intravitreal silicone oil (SO) and sterilized air on macular vasculature and structure after successful retinal repair for macular-on rhegmatogenous retinal detachment (RRD) patients.Method21 eyes (21 patients) with macular-on RRD underwent single pars plana vitrectomy following intravitreal SO or sterilized air (Gas) tamponade. Optical Coherence Tomography (OCT) and angiography were used to evaluate retinal layer thickness and flow density (FD) changes throughout the observation period of 12 weeks. Retinal layers were segmented into 7 sets: NFL, GCL + IPL, INL, OPL, ONL + IS, OS+RPE and BRM. Macular perfusion system was segmented into superficial and deep capillary plexus flow density (SCPFD, DCPFD), and choriocapillaries plexus flow density (CCPFD).ResultCompared to Gas tamponade, SO tamponade led to more decrease in both superficial and deep retinal blood flow during observation. NFL thickness was found to decrease in both Gas tamponade and SO tamponade eyes. SO tamponade resulted in more pronounced decrease which led to significant intergroup difference. Opposite changing trends were found in GCL + IPL and ONL + IS thicknesses due to different means of tamponade. SO tamponade caused thicknesses of these two segmented layers to decrease, which led to significant intergroup differences. SO tamponade also led to more decrease in INL, OPL thicknesses. No significant intergroup difference of choroidal thickness was observed.ConclusionCompared to gas, silicone oil could have more negative tamponade effects on both fundus vasculature and structure.

Progress of the application of optical coherence tomography and angiography in the diagnosis and treatment of diabetic macular edema

Diabetic macular edema is the leading cause of central vision loss and even blindness in diabetic retinopathy. Compared to FFA, OCT can obtain the high-resolution 3D image quickly, easily to reflect the details of the tissue and realize the quantitative measurement. As a novel technology, OCT angiography (OCTA) can display microvascular structure from different layers of retina and choroid, having its advantage of quantifying the vessel density and the lesion area. By detecting fundus morphology, quantifying and quantitating the retinal vessels and vessel density, the combination of OCT and OCTA could play a guiding role in diagnosis, classification, treatment and prognosis of diabetic macular edema. Key words: Tomography, optical coherence; Macular edema; Diabetic retinopathy/complications; Review

Возможности метода оптической когерентной томографии с функцией ангиографии в диагностике склерокомпрессионной макулярной дегенерации

Возможности метода оптической когерентной томографии с функцией ангиографии в диагностике склерокомпрессионной макулярной дегенерации

Choroidal neovascularization emerged right from the focal choroidal excavation in eyes with central serous chorioretinopathy post half-dose photodynamic therapy: a case report

BackgroundFocal choroidal excavation (FCE) is a common concurrent disease with central serous chorioretinopathy (CSC) and choroidal neovascularization (CNV). Photodynamic therapy (PDT) was able to cease the course of CSC with efficacy and safety. To retrospectively observed and followed up a special course in eyes with CSC and concurrent FCE treated by a half-dose of PDT.Case presentationIn this case report analysis, two eyes with CSC and concurrent FCE treated with half-dose PDT, were followed up with monthly retinal fundus examinations. Best corrected visual acuity (BCVA) and ophthalmic fundus examination were examined, including fundus photos, optical coherence tomography (OCT) and angiography. In Case 1, a 46-year-old female has been diagnosed as CSC and concurrent FCE. The baseline BCVA was 10/20. After a half-dose of PDT, complete resolution of SRF was achieved at one-month with stable BCVA. At 3 months, the patient complained of obvious metamorphosis. Multimodal images confirmed the existence of CNV, derived from the FCE, inside the zone of PDT irradiation. The development of CNV stopped promptly 1 month post the injection of ranibizumab. In Case 2, a 39 year-old male was diagnosed as bilateral CSC. The BCVA was 8/20 (od), and 16/20 (os). The multimodal images showed classic CSC manifestation in left eye, but atypical manifestation in right eye with subtle SRF and FCE. Post half-dose treatment, the SRF in left eye completely resolved at three-months, and the BCVA improved to 24/20. However, a lesion of CNV grew in the FCE after 1 month in right eye, with decreased BCVA, 4/20. One month post-injection of ranibizumab, obvious regression was witnessed, with improved BCVA, 6/20. The CNV proceeded to be a scar 2 months after injection. The BCVA maintained at 8/20.ConclusionsIn this study, type II CNV was induced in two cases of CSC concurrent with FCE in 3 months post half-dose PDT. The CNV grew right from the FCE, inside the zone of PDT irradiation.

Optical coherence tomography and angiography in patients with angioid streaks.

To investigate the retinal and choroidal features of angioid streak by fluorescein angiography (FA), indocyanine green anigography (ICG-A) and optical coherence tomography (OCT). We analysed 46 eyes of 23 patients with angioid streaks examined at our retina section between March 1998 and June 2000. Their mean age was 42.8 years (26-61 years). After a routine ophthalmological examination, OCT and simultaneous fluorescein and indocyanine green angiography (FA/ICG-A) were done. Color fundus photographs were also taken. A peau dorange appearance and angioid streaks were more numerous and apparent with ICG-A than FA. In two eyes (4.3%), some streaks that were well visualized on FA were not visible on ICG-A. Twenty eyes (43.5%) had macular complications and 26 (56.5%) were normal. Occult choroidal neovascularization (CNV) was diagnosed by ICG-A. Nine eyes had occult, and 11 had classic CNV. Ruptures of Bruchs membrane were hypofluorescent in 20 (43.5%) and hyperfluorescent in 26 eyes (56.5%). Optic disc drusen were detected in both eyes of one patient (4.3%). Localized hyperreflectivity was thought to be due to calcium deposits. Angioid streaks were visualized more clearly and in larger numbers by ICG-A than FA. However, in some cases streaks that were funduscopically and fluorescein angiogrpahically visible could not be seen by ICG-A. Occult CNV was detected by ICG-A. Some mottled areas were seen and more clearly visualized by ICG-A. Calcium deposits were observed as localized areas of hyperreflectivity on OCT. These findings indicate that fluorescein angiography, ICG-A and optical coherence tomography all provide supportive information for each other and can be used for either diagnosis or follow-up of those patients. (Eur J Ophthalmol 2002; 12: 473-81).

Fusion of optical coherence tomography and angiography for numerical simulation of hemodynamics in bioresorbable stented coronary artery based on patient-specific model

Three-dimensional simulations of coronary artery using finite element analysis are considered as effective means to understand the biomechanical properties after the stent was deployed. Bioresorbable vascular scaffolds are new-generation stents used by people. Intravascular optical coherence tomography is an emerging technique for detecting struts. The common 3 D reconstruction methods are using Intravascular Ultrasound (IVUS) or angiographies. However, it loses the details about geometry model. Fusing of optical coherence tomography and angiography to reconstruct the bioresorbable stented coronary artery based on patient-specific mode is an innovative method to reconstruct the high fidelity geometry. This study aimed to use computer-aided design models and computational fluid dynamics research tools to conduct a systematic investigation of blood flow in an isolated artery with realistically deployed coronary stents. Some important hemodynamic factors such as wall shear stress, wall pressure and streamline were calculated. The doctors could evaluate the local hemodynamic alterations within coronary arteries after stent deployment by reconstructing the high-fidelity geometry about each clinical case.

OCT-Angiography for monitoring and managing neovascular age-related macular degeneration

ABSTRACTPurpose: To evaluate the combined use of optical coherence tomography and angiography (OCT-A) for imaging choroidal neovascularization (CNV) secondary to neovascular age-related macular degeneration (nAMD).Materials and Methods: This prospective observational study was conducted from May 2015 to April 2017. Included in the study were 54 patients (n = 63 eyes), all of whom had CNV secondary to nAMD and all of whom had been examined by OCT-A. Angioscans (3x3 and 6 × 6) and conventional B-scan OCT scans were obtained for all patients at baseline and at various times during the 24-month follow-up period. For diagnostic confirmation, conventional imaging methods fluorescein angiography (FA) and indocyanine green angiography (ICGA) were performed at baseline. A total of 13 patients (n = 15 eyes) underwent serial imaging during 34 follow-up visits. The main outcomes included (i) determination of OCT-A sensitivity for the detection of CNV (classic and occult) and (ii) the correlation between B-scan OCT and OCT-A vis-à-vis consecutive follow-up changes.Results: At baseline, the detection rate (i.e., overall sensitivity) of OCT-A for detecting CNV was 64.4% (75.7 and 48.0% for classic and occult CNV, respectively), independent of prior treatment status. In terms of quality, 6 × 6 angioscans were superior to 3 × 3. Moreover, specific CNV morphologic patterns by B-scan OCT did not correlate with lesion composition. Correspondence between OCT-A and B-scan OCT was observed in only 53% of the cases.Conclusions: OCT-A may prove to be a valuable adjunctive diagnostic tool for the interpretation of CNV, as it not only reduces the need for invasive angiographic procedures but also facilitates the follow-up process.

2036Optical coherence tomography plus angiography versus angiography alone to guide percutaneous coronary intervention: outcomes from the Pan-London PCI Cohort

2036Optical coherence tomography plus angiography versus angiography alone to guide percutaneous coronary intervention: outcomes from the Pan-London PCI Cohort

OP70 Economic Impact Of Macular Edema Diseases, A Retrospective Study

INTRODUCTION:Inhibitors of Vascular Endothelial Growth Factor (VEGF) have made possible the treatment of the Retinal Vascular Diseases (RVD) for which there were limited therapeutic resources. The aim of this work was to estimate annual direct costs of major macular edema diseases in Italy in particular Choroidal Neovascularization (CNV), Diabetic Macular Edema (DME) and Retinal Vein Occlusions (RVO) from the hospital perspectives.METHODS:This descriptive study was aimed at quantifying direct costs incurred by five hospitals in Italy. Administrative and clinical databases of Policlinico Tor Vergata in Rome were analyzed for a 6-year period. In this context, it was possible to stratify patients depending on the disease and number of eyes treated. From these results, a survey with structured questionnaires was developed involving four other hospitals in Italy. Thanks to that, direct costs (drugs and specialist) were estimated from the hospitals perspective in 2016.RESULTS:Interviews included 7,356 individuals of which 1,860 were treated in both eyes. Within the considered five hospitals, 64 percent of treated patients had CNV, 21 percent DME, and 15 percent RVOs. The average annual administration rate of anti-VEGF treatment resulted in 4.03 (Standard Deviation, SD 3.46) per patient eye: 4.69 (SD 1.75) for cases enrolled for less than one year (naïve) and 3.38 (SD 0.82) per patients treated for more than one year (experienced). Naïve patients had a mean per capita annual cost of EUR2,368 per eye (EUR2,536 for CNV; EUR2,280 RVO; EUR1,986 DME) of which EUR2,952 was related to the administration of on-label drugs mainly Eylea, Lucentis, Macugen, Ozurdex and EUR49 due to off-labels such as Avastin. Experienced patients average annual cost per eye was EUR1,689: EUR2.179 for the on-label drugs, EUR34 due to off-labels (EUR1,839 for CNV; EUR1,327 RVO; EUR1,399 DME). The average rate of the specialist annual visit was four times; the most frequent types were Optical Coherence Tomography (OCT), Angiography, and Fundus Photography (FP).CONCLUSIONS:This is a first attempt to study direct costs incurred from the hospital perspective associated with RVD with overexpression of VEGF in Italy. This might represent a first step for further analysis assessing the burden of RVD diseases from the Italian National Health System perspective globally.

Long-term follow-up of renal arteries after radio-frequency catheter-based denervation using optical coherence tomography and angiography

Optical coherence tomography (OCT) imaging at the time of renal denervation (RDN) showed that procedure might cause spasm, intimal injury or thrombus formation. In the present study, we assessed the healing of renal arteries after RDN using OCT and renal angiography in long-term follow-up. OCT and renal angiography were performed in 12 patients (22 arteries) 18.41±5.83months after RNS. There were no adverse events or complications during the long-term follow-up. In ten patients (83%), significant reductions of blood pressure was achieved without a change of the antihypertensive medications. We demonstrated the presence of 26 areas of focal intimal thickening identified by OCT in 10 (83%) patients and in 14 (63%) arteries. The mean area of focal intimal thickening was 0.054±0.033mm(2). No vessel dissection, thrombus, intimal tear or acute vasospasm were observed during the OCT analysis. Also, the quantitative angiography analysis revealed a significant reduction of the minimal and proximal lumen diameters at follow-up as compared to measurements obtained before RDN. Renal arteries have a favorable "long-term" vessel healing response after RDN. Focal intimal thickening and a modest reduction of the minimal lumen diameter may be observed after RF denervation. Further studies are needed to determine whether intravascular imaging may be helpful in evaluating the vessel healing of RF RDN.