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Featured researches published by Alexandra Miere.


American Journal of Ophthalmology | 2016

Optical Coherence Tomography Angiography in Retinal Vein Occlusion: Evaluation of Superficial and Deep Capillary Plexa.

Florence Coscas; Agnès Glacet-Bernard; Alexandra Miere; Violaine Caillaux; Joel Uzzan; Marco Lupidi; Gabriel Coscas; Eric H. Souied

PURPOSE To evaluate the optical coherence tomography angiography (OCT angiography) appearance of the superficial and deep capillary plexa in eyes with retinal vein occlusion (RVO) and to compare these findings with those of fluorescein angiography (FA) and spectral-domain optical coherence tomography (SD OCT). DESIGN Retrospective observational case series. METHODS Patients presenting with RVO to Creteil University Eye Clinic were retrospectively evaluated. All patients had undergone a comprehensive ophthalmic examination including FA, SD OCT, and OCT angiography. RESULTS There were 54 (31 male, 57%) RVO patients with a mean age of 70 years. The perifoveal capillary arcade was visible in 52 of 54 eyes (96%) on OCT angiography and in 45 eyes (83%) on FA; this arcade was disrupted in 48 eyes (92%) and 39 eyes (72%) on OCT angiography and FA, respectively (P = .002). Perifoveal capillary arcade disruption was correlated with peripheral retinal ischemia (P = .025). Intraretinal cystoid spaces were observed in 34 eyes (68%) using FA, in 40 eyes (76%) using SD OCT, and in 49 eyes (90%) using OCT angiography (P = .008 for OCT angiography vs SD OCT and P = .001 for OCT angiography vs FA). Retinal capillary network abnormalities were observed in all patients in both superficial capillary plexus and deep capillary plexus on OCT angiography. Nonperfusion grayish areas were more frequent in the deep capillary plexus (43 eyes, 84%) than in the superficial capillary plexus (30 eyes, 59%, P < .001). CONCLUSION OCT angiography can simultaneously evaluate both macular perfusion and edema. For the first time, an imaging technique enables the evaluation of the deep capillary plexus, which appears to be more severely affected than the superficial capillary plexus in RVO.


Investigative Ophthalmology & Visual Science | 2016

Normative Data for Vascular Density in Superficial and Deep Capillary Plexuses of Healthy Adults Assessed by Optical Coherence Tomography Angiography.

Florence Coscas; Alexandre Sellam; Agnès Glacet-Bernard; Camille Jung; Mathilde Goudot; Alexandra Miere; Eric H. Souied

PURPOSE To establish a normative database for vascular density (VD) and foveal avascular zone (FAZ) at the superficial (SCP) and deep capillary plexus (DCP) in healthy subjects with optical coherence tomography (OCT) angiography. METHODS The study was a retrospective chart review of healthy patients who had undergone OCT angiography imaging. A 3- × 3-mm area, centered on the fovea, was scanned for all the study eyes. The automated segmentation allowed separate analysis of the SCP, the DCP, and a comprehensive C-scan including both vascular layers. On the obtained images, VD and FAZ measurements were computed. Interobserver reproducibility and intraobserver repeatability were also assessed. RESULTS A total of 135 eyes of 70 subjects (51% male) were analyzed. The mean age was 48.3 ± 17.5. We divided patients into group 1, from 20 to 39 years of age; group 2, from 40 to 59 years; and group 3, age 60 years or older. At the level of the SCP, mean VD and mean FAZ ± SD were, respectively, 52.58 ± 3.22% and 0.28 ± 0.1 mm2. At the level of the DCP, mean VD and mean FAZ were 57.87 ± 2.82% and 0.37 ± 0.12 mm2, respectively. The mean VD was significantly higher (P < 0.05) in DCP compared with SCP in all Early Treatment Diabetic Retinopathy Study (ETDRS) sectors and in all age groups. Vascular density was higher in women than in men after 60 years (P < 0.01). After adjustment on the signal strength index (SSI), the mean VD remained directly correlated with the age range and sex. The mean FAZ area was lower in group 3 (P < 0.05). Interobserver reproducibility was 0.78 to 0.99 in SCP and 0.67 to 0.92 in DCP, and intraobserver repeatability was 0.64 to 0.93 in SCP and 0.63 to 0.87 in DCP. CONCLUSIONS Our study has provided, for the first time, age-related VD mapping data using OCT angiography in healthy subjects. The prototype software used in this study may help to improve the concept of VD grading with high inter- and intraexaminer repeatability and interexaminer reproducibility.


Retina-the Journal of Retinal and Vitreous Diseases | 2015

Type 2 Neovascularization Secondary To Age-related Macular Degeneration Imaged By Optical Coherence Tomography Angiography

Ala El Ameen; Salomon Y. Cohen; Oudy Semoun; Alexandra Miere; Mayer Srour; Maddalena Quaranta-El Maftouhi; Hassiba Oubraham; Rocio Blanco-Garavito; Giuseppe Querques; Eric H. Souied

Purpose: Optical coherence tomography angiography is a novel and noninvasive technique for imaging retinal microvasculature by detecting changes in reflectivity that is related to blood flow. The purpose of this study was to describe Type 2 neovascularization characteristics in age-related macular degeneration using optical coherence tomography angiography. Methods: Fourteen eyes of 14 consecutive patients with Type 2 neovascularization were prospectively included. All patients underwent a complete ophthalmological examination, including color and infrared fundus photography, fluorescein and indocyanine green angiography, spectral domain optical coherence tomography angiography, and optical coherence tomography angiography. Results: In all cases, Type 2 lesions could be detected by optical coherence tomography angiography, presenting as a hyperflow lesion in the outer retina, with a glomerulus (4/14) or medusa shape (10/14), surrounded by a dark halo. The superficial layer and the deep retina showed no abnormal flow. Surprisingly, the Type 2 lesions could also be observed in the presumed choriocapillaris layer. These glomerulus- or medusa-shaped lesions were connected, in 10/14 eyes, to a thicker main branch, which seemed to continue deep into the choroidal layers. Conclusion: Optical coherence tomography angiography may be a new imaging method for the diagnosis of Type 2 neovascularization in clinical routine. However, the specificity of the features needs to be investigated in further studies.


Journal of Ophthalmology | 2015

Optical Coherence Tomography Angiography in Central Serous Chorioretinopathy

Eliana Costanzo; Salomon Y. Cohen; Alexandra Miere; Giuseppe Querques; Vittorio Capuano; Oudy Semoun; Ala El Ameen; Hassiba Oubraham; Eric H. Souied

Purpose. To analyze optical coherence tomography angiography (OCTA) findings in eyes with central serous chorioretinopathy (CSC) and to compare them with those obtained with multimodal imaging. Methods. A series of consecutive patients diagnosed with CSC, underwent OCTA and multimodal imaging, including spectral domain OCT, fluorescein, and indocyanine green angiography. OCTA images were performed at three main depth intervals: automatically segmented outer retina, manually adjusted outer retina, and automatically segmented choriocapillaris. Results. Thirty-three eyes of 32 consecutive patients were analyzed. OCTA showed 3 main anomalies at the choriocapillaris: the presence of dark areas (19/33 eyes) which were frequently associated with serous retinal detachment, presence of dark spots (7/33 eyes) which were frequently associated with retinal pigment epithelium detachment, and presence of abnormal vessels (12/33 eyes) which were frequently, but not systematically, associated with choroidal neovascularization, as confirmed by multimodal imaging. Conclusions. OCTA revealed dark areas and dark spots, which were commonly observed. An abnormal choroidal pattern was also observed in one-third of cases, even when multimodal imaging did not evidence any choroidal neovascularization. Abnormal choroidal vessels should be interpreted with caution, and we could assume that this pathological choroidal vascular pattern observed in many CSC cases could be distinct from CNV.


Retina-the Journal of Retinal and Vitreous Diseases | 2015

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN EARLY TYPE 3 NEOVASCULARIZATION.

Alexandra Miere; Giuseppe Querques; Oudy Semoun; El Ameen A; Capuano; Eric H. Souied

Purpose: To report the imaging features of Type 3 neovascularization secondary to exudative age-related macular degeneration on optical coherence tomography angiography (OCTA). Methods: All consecutive treatment-naive patients diagnosed with early-stage Type 3 neovascularization underwent imaging by color retinal photographs or multicolor imaging, fluorescein angiography, indocyanine green angiography, spectral domain optical coherence tomography, and OCTA. The OCTA features were analyzed and correlated with the findings of conventional angiography and spectral domain optical coherence tomography. Results: A total of 18 treatment-naive eyes of 18 consecutive patients (13 females and 5 males; mean age 81.3 ± 6.0) were included in the analysis. Optical coherence tomography angiography showed lesions characterized by a retinal–retinal anastomosis that emerged from the deep capillary plexus, forming in all 18 eyes a clear tuft-shaped high-flow network in the outer retinal segmentation, finally abutting in the subretinal pigment epithelium space. In 15 of 18 eyes, in the choriocapillaris segmentation, there appeared a small clew-like lesion, which in 2 cases seemed connected with the choroid through a small caliber vessel. Conclusion: Optical coherence tomography angiography of treatment-naive Type 3 neovascularization showed almost constantly a high-flow, tuft-shaped abnormal outer retinal proliferation, frequently associated to a small clew-like lesion in the choriocapillaris layer.


Retina-the Journal of Retinal and Vitreous Diseases | 2015

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FEATURES OF SUBRETINAL FIBROSIS IN AGE-RELATED MACULAR DEGENERATION.

Alexandra Miere; Oudy Semoun; Salomon Y. Cohen; Alaʼa El Ameen; Mayer Srour; Camille Jung; Hassiba Oubraham; Giuseppe Querques; Eric H. Souied

Purpose: To report the imaging features of subretinal fibrosis secondary to exudative age-related macular degeneration (AMD) on optical coherence tomography angiography. Methods: All consecutive patients diagnosed with subretinal fibrosis complicating exudative AMD were imaged by color retinal photographs or multicolor imaging, fluorescein angiography, spectral domain optical coherence tomography, and optical coherence tomography angiography. Eyes with active exudative features observed during the last 6 months were compared with those without any sign of exudation >6 months. Results: Forty-nine eyes of 47 consecutive patients were included. A blood flow inside the fibrotic scar could be detected in 46 of 49 cases (93.8%). Three patterns of vascular networks could be distinguished, that were described as pruned vascular tree (26 of 49 eyes; 53.1%), tangled network (14 of 49; 28.6%), and/or vascular loop (25 of 49; 51.0%). Furthermore, 2 types of hyporeflective structures, large flow void, and/or dark halo were observed in 63% and in 65% of eyes, respectively. The observed patterns did not differ between eyes with active or inactive lesions. Conclusion: Optical coherence tomography angiography of subretinal fibrosis showed almost constantly a perfused, abnormal vascular network and collateral architectural changes in the outer retina and the choriocapillaris layer. These features were associated with both active and inactive fibrotic choroidal neovessels.


British Journal of Ophthalmology | 2016

Optical coherence tomography angiography characteristics of polypoidal choroidal vasculopathy.

Mayer Srour; Giuseppe Querques; Oudy Semoun; Ala El Ameen; Alexandra Miere; Anne Sikorav; Olivia Zambrowski; Eric H. Souied

Purpose To analyse the morphological characteristics of polypoidal choroidal vasculopathy (PCV) on optical coherence tomography angiography (OCT-A). Methods Prospective study with consecutive patients affected with PCV were included. All patients underwent a complete ophthalmological examination including fundus photography, fluorescein angiography, indocyanine green angiography, spectral-domain OCT and OCT-A. Results Twelve eyes of 12 patients (mean age 72.6±10.5 years; 4 men and 8 women) were included for analysis. In all eyes (12/12) the segmentation of the choriocapillaris layer on OCT-A revealed the branching vascular network (BVN) as a hyperflow lesion. OCT-A segmentation of the choriocapillaris layer in correspondence of the polypoidal lesion showed in 3/12 eyes (25%) a hyperflow round structure, surrounded by a hypointense halo, and in 9/12 eyes (75%) a hypoflow round structure. Conclusions The OCT-A is a non-invasive imaging modality allowing the visualisation of different structures in PCV. The BVN is constantly clearly detected. The hypoflow round structure appearance of the polyp in OCT-A, is probably due to an unusual blood flow inside the polypoidal lesions, contrasting with the BVN. Further improvement in OCT-A knowledge will provide information on the specificity of the different intensity characteristics in PCV.


Developments in ophthalmology | 2016

Optical Coherence Tomography Angiography Features of Type 3 Neovascularization in Age-Related Macular Degeneration

Giuseppe Querques; Alexandra Miere; Eric H. Souied

PURPOSE To characterize the imaging features of type 3 neovascularization secondary to exudative age-related macular degeneration on optical coherence tomography (OCT) angiography (OCTA). METHODS Patients diagnosed with treatment-naïve early-stage type 3 neovascularization underwent multimodal imaging, including color retinal photography or multicolor imaging, fluorescein angiography, indocyanine green angiography, spectral-domain OCT and OCTA. The OCTA features of type 3 neovascularization were analyzed and correlated with the findings on angiography and spectral-domain OCT. RESULTS OCTA showed lesions characterized by a retinal-retinal anastomosis. These lesions emerged from the deep capillary plexus and formed a clear, tuft-shaped, high-flow network in the outer retinal segment in all eyes, abutting in the subretinal pigment epithelium space. In most cases, a small, clew-like lesion was present in the choriocapillaris segment. Moreover, in some cases, this clew-like lesion seemed to be connected to the choroid through a small-caliber vessel. CONCLUSION OCTA of treatment-naïve type 3 neovascularization shows high-flow, tuft-shaped, abnormal outer retinal proliferation that is almost consistently associated with a small, clew-like lesion in the choriocapillaris layer.


Retina-the Journal of Retinal and Vitreous Diseases | 2017

Qualitative And Quantitative Follow-up Using Optical Coherence Tomography Angiography Of Retinal Vein Occlusion Treated With Anti-vegf: Optical Coherence Tomography Angiography Follow-up of Retinal Vein Occlusion

Alexandre Sellam; Agnès Glacet-Bernard; Florence Coscas; Alexandra Miere; Gabriel Coscas; Eric H. Souied

Purpose: To evaluate changes of vascular flow of patients treated with intravitreal injections of anti-vascular endothelial growth factor for macular edema secondary to retinal vein occlusion (RVO) with optical coherence tomography angiography (OCTA). Methods: Patients with RVO with macular edema and treated with intravitreal injections of anti-vascular endothelial growth factors were retrospectively evaluated. The following examinations were performed before and after treatment: best-corrected visual acuity, spectral domain optical coherence tomography, fluorescein angiography, and OCTA (Optovue, Inc). Automatic measurement of vascular density of the superficial and deep capillary plexus was also performed and compared with age- and sex-matched healthy subjects. Results: Twenty-eight eyes of 28 patients (mean age 66.2 years; males 19%) were evaluated, including 13 central RVO, 11 branch RVO, and 4 hemicentral RVO. After treatment, mean central macular thickness significantly decreased from 644 &mgr;m to 326 &mgr;m and best-corrected visual acuity increased from 20/125 to 20/63 (P < 0.01 for both results). On OCTA, perifoveal capillary disruption (P = 0.029) and the number of cysts in the superficial capillary plexus and deep capillary plexus (P < 0.002) significantly decreased after treatment. The mean vascular density in the superficial capillary plexus slightly decreased during follow-up from 46.44% to 45.01% (not significantly). These densities were significantly less than those observed in healthy controls (P < 0.001). Conclusion: Optical coherence tomography angiography showed regression of macular edema, reduced capillary disruption and cysts, and slight decrease in mean macular vascular density with time and despite treatment. Thus, OCTA enables qualitative and quantitative evaluation during follow-up of patients treated for RVO.


British Journal of Ophthalmology | 2016

Optical coherence tomography angiography in adult-onset foveomacular vitelliform dystrophy

Giuseppe Querques; Olivia Zambrowski; Federico Corvi; Alexandra Miere; Oudy Semoun; Mayer Srour; Eric H. Souied

Purpose To describe structural features of eyes with adult-onset foveomacular vitelliform dystrophy (AFVD) on optical coherence tomography angiography (OCT-A) and to evaluate the ability to detect the presence of choroidal neovascularisation (CNV). Methods Consecutive patients presenting at the University Eye Clinic of Creteil with diagnosis of AFVD were included. All patients underwent a complete ophthalmological examination, including fundus autofluorescence, fluorescein angiography, indocyanine green angiography, spectral domain optical coherence tomography and OCT-A by Optovue RTVue XR Avanti. Results Twenty-two eyes of 18 consecutive patients (8 women and 10 men; 68±12.8 years) were included. On OCT-A the presence of subretinal material leads to displacement of blood vessels at both the superficial and deep capillary plexuses of the retina. In one case, these vascular abnormalities were associated with long filamentous vessels running thorough the foveal avascular area. In all cases, a rarefaction of the choriocapillaris was also observed. In two eyes OCT-A distinctly disclosed the presence of a CNV secondary to AFVD while conventional imaging did not show clearly the neovascularisation due to masking effect of the subretinal vitelliform material. Conclusions In patients with AFVD, OCT-A showed vascular network rarefaction with less blood vessels at the superficial and deep capillary plexuses, and the choriocapillaris layer. These vascular abnormalities may play a role in the pathogenesis or simply represent a consequence of material accumulation and reabsorption in AFVD. In two cases, the conventional imaging did not show clearly the neovascularisation due to masking effect of the subretinal vitelliform material, while OCT-A showed distinctly the CNV.

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Giuseppe Querques

Vita-Salute San Raffaele University

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Eliana Costanzo

Seconda Università degli Studi di Napoli

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