ABSTRACT
La tomografía de coherencia óptica se ha convertido en el sistema de imagen más común para detectar de manera precoz el daño glaucomatoso; de ahí que resulte imprescindible para las decisiones clínicas y como criterio de inclusión en investigaciones y ensayos clínicos. El objetivo es exponer los avances en la aplicación de la tomografía de coherencia óptica en la detección del glaucoma a través de la revisión de las publicaciones de los últimos cinco años. La búsqueda se realizó en Google Académico para lo cual se emplearon palabras clave. Las mejoras en la tecnología de dominio espectral y de fuente de barrido han permitido la segmentación de células ganglionares, el reconocimiento de la apertura de la membrana de Bruch como punto de referencia para el análisis de los parámetros del disco óptico y el desarrollo de la angiografía sin contraste. Para el diagnóstico de glaucoma se analizó la estructura en tres localizaciones (células ganglionares maculares, capa de fibras neuroretiniana peripapilar, anillo neuroretiniano y copa en el disco óptico) y el plexo vascular superficial en dos (parafoveal y peripapilar). Se recomienda chequear calidad y presencia de artefactos previo al análisis de los resultados; así como complementar estos resultados con el interrogatorio y hallazgos al examen oftalmológico, fundamentalmente mediante biomicroscopia de polo posterior, para minimizar posibilidad de errores diagnósticos. Es útil tener esto en cuenta, a pesar de que sea numerosa la cantidad de pacientes que acuden cada día a la clínica del glaucoma. Se señalan ventajas y limitaciones de los parámetros estructurales y vasculares en el diagnóstico de glaucoma.
Optical coherence tomography has become the most common imaging system for early detection of glaucomatous damage; hence, it is essential for clinical decisions and as a criterion for inclusion in research and clinical trials. The objective is to present the advances in the application of optical coherence tomography in the detection of glaucoma by reviewing the publications of the last five years. The search was performed in Google Scholar using keywords. Improvements in spectral domain and scanning source technology have allowed the segmentation of ganglion cells, the recognition of Bruch's membrane aperture as a reference point for the analysis of optic disc parameters and the development of non-contrast angiography. For the diagnosis of glaucoma, the structure was analyzed in three locations (macular ganglion cells, peripapillary neuroretinal fiber layer, neuroretinal ring and optic disc cup) and the superficial vascular plexus in two (parafoveal and peripapillary). It is recommended to check quality and presence of artifacts prior to the analysis of the results; as well as to complement these results with the interrogation and findings on ophthalmologic examination, mainly by posterior pole biomicroscopy, to minimize the possibility of diagnostic errors. It is useful to keep this in mind, despite the large number of patients that come to the glaucoma clinic every day. Advantages and limitations of structural and vascular parameters in the diagnosis of glaucoma are pointed out.
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Objective: To evaluate the effect of uncomplicated cataract surgery on macular and optic nerve head blood flow with Optical Coherence Tomography Angiography (OCT-A). Retinal vascular changes and macular vessel remodeling following cataract surgery is an area of interest, as the effect, cause and duration of such changes remain debatable.Setting: Eye Department, Red Cross Tertiary General Hospital, Athens, Greece.Methods: In this study, we recruited cataract surgery candidates who had regular post operative visits and underwent longitudinal OCT-A examinations before and after surgery.Results: Macular vessel density increased in the post operative visits both in the superficial (SCP) and deep capillary network (DCP) (P<0.001) and showed a persistent effect over 3 months follow-up. Macular thickness increased over the first postoperative month, but returned to preoperative values at 3 months. Foveal avascular zone (FAZ) measurements and vessel density at radial peripapillary capillaries (RPC) were unaffected.Conclusions: OCT-A enables a quantitative analysis of blood flow by regular patient monitoring. In this study, we found that after cataract surgery, macular blood flow increased significantly. The reason for this could be attributed to post operative inflammatory process or vascular remodeling due to change in retinal metabolic demands.
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@#A 30-year-old, monocular myopic female consulted for new onset scotoma on her left eye. Best corrected visual acuity was 20/20 for the left eye. Fundus exam revealed a hypopigmented lesion in the inferior juxtafoveal area with no overlying vitreous reaction/opacity. Spectral domain optical coherence tomography (SD-OCT) showed focal disruption and elevation of the inner choroid and retinal pigment epithelium (RPE), indicating punctate inner choroidopathy (PIC). OCT angiography (OCT-A) revealed the presence of a choroidal neovascular membrane (CNV) on RPE-RPE fit segmentation. The CNV and lesion resolved upon treatment with one intravitreal bevacizumab injection and oral prednisone 60 mg (1.2 mg/kg body weight) per day tapering over 2 months. This is the first reported case of PIC in a Filipino that was diagnosed and treated with the guidance of high-resolution SD-OCT and OCT-A. These diagnostic tests proved useful in identifying the lesions based on cross-sectional views of the retina, RPE and choroid.
Subject(s)
White Dot SyndromesABSTRACT
Objective@#This study compared the peripapillary retinal nerve fiber layer (pRNFL) microangiographic properties [vessel area density (VAD) and blood flux index (BFI)] of unilateral open-angle glaucomatous eyes to contralateral eyes-at-risk, and to eyes of healthy age- and sex-matched subjects.@*Methods@#This was a single-center, case-control study of Filipinos diagnosed with unilateral primary openangle glaucoma (POAG) or normal-tension glaucoma (NTG). Mean overall and quadrantal VAD and BFI of the three groups were measured with optical coherence tomography- angiography (OCT-A). Area under the receiver operating characteristic (AROC) was used to measure diagnostic ability.@*Results@#Twenty-two (22) glaucomatous subjects (15 POAG and 7 NTG eyes), 22 contralateral eyes-at-risk, and 22 normal eyes from age- and sex-matched control subjects completed the study. Eyes with glaucoma showed lower mean overall VAD (40%) and BFI (0.37) compared to eyes-at-risk (44.4% and 0.42, respectively; p <0.001) and control eyes (45.6% and 0.44, respectively; p <0.001). Mean VAD and BFI values of eyes-at-risk and control groups did not significantly differ from each other. Overall pRNFL thickness showed highest diagnostic accuracy for glaucoma (AROC = 0.97), followed by VAD (0.94), and BFI (0.88) (p=0.46).@*Conclusion@#VAD and BFI were significantly diminished in unilateral open-angle glaucoma, suggesting that the utility of OCT-A in the detection of glaucoma is comparable to pRNFL thickness.
Subject(s)
Microcirculation , Glaucoma , AngiographyABSTRACT
@#AIM:To evaluate the short-term efficacy and safety of intravitreal dexamethasone implant(IDI)for patients with retinal vein occlusion-related macular edema(RVO-ME)by using optical coherence tomography(OCTA).<p>METHODS: Seventeen eyes in 17 patients with RVO-ME were treated with intravitreal injection of sustained-release IDI. The best corrected visual acuity(BCVA), central macular thickness(CMT)and superficial retinal vascular network were observed at baseline, 1d, 1mo, 2mo, 3mo, 4mo and 6mo.<p>RESULTS: CMT was significantly reduced from baseline by 24h after injection and improved further during the 3mo follow-up, and the improvement of visual acuity was consistent with that of CMT. OCTA showed improvement from baseline in terms of decreased number and size of cysts and restoration of the retinal vascular network. A slight increase in intraocular pressure was observed in 2 eyes after injection. There were no systemic side effects associated with injection or medication during follow-up.<p>CONCLUSION: CMT reduced as early as 24h after the injection of IDI, with further reduction during follow-up, and OCTA could visually observe the changes of retinal vascular network in macular area.
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Purpose: Diagnosis of choroidal neovascular membrane (CNVM) is difficult in chronic central serous chorioretinopathy (CCSC) due to overlapping features of both on conventional dye angiography. Optical coherence tomography angiography (OCTA) allows a quick and noninvasive detection of CNVM in these eyes. We compared the fluorescein angiography (FA) features of CNVM with those of OCTA to assess the role of FA in detecting CNVM in CCSC eyes. Methods: Patients with CCSC undergoing FA, spectral domain (SD)-OCT, and OCTA were identified (March 2015–June 2015). Four retina specialists individually reviewed FA images (without OCTA and SD-OCT) to determine whether CNVM was present. In parallel, two other retina specialists reviewed all images (FA/SD-OCT/OCTA) for CCSC features and confirmed whether CNVM was present using OCTA as the gold standard. The inter- and intraobserver variability was measured by Kappa (k) coefficient. The FA features of CNVM were compared and correlated with those on OCTA. Results: Of 43 eyes (26 patients, mean age 45.6 ± 8.5 years, all males), a definite CNVM (detected by OCTA) was present in nine (20.9%) eyes. FA alone detected CNVM in 13 (30.2%) eyes [sensitivity 44.4% (95% confidence interval (CI): 11.9–76.9), specificity 73.5% (95% CI: 58.7–88.3), positive and negative predictive values 30.8% and 83.3%, respectively, and accuracy 67.44% (95% CI: 53.4–81.4)]. Conclusion: When compared with OCTA, the FA was unable to characterize CNVM in CCSC (with a very low sensitivity and moderate specificity) as none of the specific dye leakage patterns on FA correlated with CNVM seen on OCTA, limiting its usefulness and accuracy in detecting CNVM in these eyes.
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Optical coherence tomography (OCT) angiography is a promising technique that provides depth resolved images of blood flow in the retina and choroid with levels of detail far exceeding that obtained with older forms of imaging and offers several advantages over conventional angiography to visualize the chorioretinal vasculature in a rapid and noninvasive manner. However, as with any evolving imaging technique, there are ongoing challenges in terms of need for new equipment, limitations of imaging capability and software processing techniques, as well as in understanding the implications of the imaging and its correlation with pathophysiology of the retina and choroid. This expert panel discussion is structured to provide an insight into the current state of OCT angiography.
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Background Myopic maculopathy leads to visual function damage.Conventional methods for the identification of choroidal neovascularization (CNV) of myopic maculopathy are fundus fluorescine angiography (FFA) and spectral-domain OCT (SD-OCT),but FFA is an invasive process and SD-OCT is incapable to image CNV well.OCT angiography (OCTA),a novel and non-invasive vascular technique,appears to be dominant in enface imaging of CNV,however,its clinical value remains to be evaluated.Objective This study was to evaluate the application of OCTA in imaging CNV of myopic maculopathy.Methods A prospective serial cases-observational study was performed.Forty-two eyes of 40 patients of myopic maculopathy were included in Ophthalmic Center,Renmin Hospital of Wuhan University from January to October 2015,with the diopter (-10.5 ± 3.74) D.Comperehensive optical and imaginal examinations were carried out in all the eyes,including fundus photography,FFA,SD-OCT and OCTA.Ranibizumab (0.5 mg/0.05 ml) was intravitreally injected in 35 eyes of 35 patients under the informed consent and SD-OCT and OCTA were examined 1 day,1 week and subsequent each month after injection.FFA was examined 1 month after injection.The patients were followed-up for 1-6 months to evaluate the clinical values of OCTA in monitoring the CNV of myopic maculopathy.This study followed the Helsinki Declaration and was approved by the Ethics Committee of Renmin Hospital of Wuhan University.Written informed consent was obtained from each patient prior to any medical examination.Results All the affected eyes showed dye leakage in CNV lesions by FFA and high reflection signal of abnormal choroidal vascular network throughout retinal pigment epithelium by SD-OCT.Clusters of high signal CNV image was clearly visible in the lesions by OCTA,and these signals were able to be displayed on both choriocapillary layer and outer layer of retina more clearly than FFA in 31 eyes of 31 patients.In 35 eyes of 35 patients received intravitreal injection of ranibizumab,CNV images on both choriocapillary layer and outer layer of retina from OCTA shrinked 1 week after injection and the lesions were stable 1 month after injection.Conclusions OCTA can display CNV of myopic maculopathy on the retinal outer layer and choriocapillary layer more clearly than FFA.Significant changes in the CNV net can be observed by OCTA 1 week after intravitreal injection of ranibizumab.OCTA plays an important role during the following-up of CNV therapy.