Choroidal Neovascularization Flow Research Articles

Association between choriocapillaris flow deficit and choroidal neovascularization activity in eyes with myopic choroidal neovascularization

Although choriocapillaris flow deficit (CFD) around choroidal neovascularization (CNV) is less associated with CNV activity in myopic eyes, no reports are investigating its size as an indicator of CNV activity. We investigated the relationship between CFD and high myopia-related CNV. In this retrospective, observational study, patients underwent optical coherence tomography angiography (OCTA) with split-spectrum amplitude-decorrelation angiography for diagnosing pathological myopic CNV (mCNV); CFD features around CNV margins were evaluated. Of the 33 eyes (30 patients), 11 (33.3%) had active mCNV, and 22 (66.7%) had inactive CNV. Six eyes (18.2%) were treatment-naïve, while the remainder previously underwent anti-vascular endothelial growth factor therapy. On OCTA, blood flow signals were detected in CNV in the outer retinal layer in 28 (84.8%) eyes, including all active cases (11 cases) and 17 (77.3%) of 22 inactive cases. CNV flow signal size correlated significantly with activity (P < 0.001). CFD around CNV was observed in 24 eyes (72.7%), including all active cases (11 cases) and 13 (59.1%) of 22 inactive cases. CFD size correlated significantly with CNV activity (P < 0.001). The size of both the CFD area around CNV and CNV flow signal area are useful indicators of CNV activity in eyes with mCNV, which may help determine treatment timing.

Result of intravitreal aflibercept injection for myopic choroidal neovascularization

BackgroundThe current study aimed to evaluate the efficacy of intravitreal aflibercept injections as the primary treatment for subfoveal/juxtafoveal myopic choroidal neovascularization (CNV) by using optical coherence tomography (OCT). Optical coherence tomography angiography (OCTA) was further used for some patients to detect the changes of CNV after treatment.MethodsIn the present study, 21 treatment-naive eyes of 21 patients with subfoveal/juxtafoveal myopic CNV received primary intravitreal aflibercept injections and were under follow-up for a minimum duration of 12 months. Among the 21 patients, 12 underwent OCTA to evaluate the changes in central foveal thickness, selected CNV area, and flow area.ResultsThe mean best-corrected visual acuity (BCVA) pertaining to all the patients significantly improved from the baseline value of 0.7 to 0.3 logMAR after treatment for 12 months (P = 0.001). However, the improvements in the median BCVA after treatment for three and 12 months were not statistically significant in the younger group (< 50 years), compared to the older group (≥ 50 years). One aflibercept injection resolved the CNV in 47.6% (10/21) of the patients. The younger group displayed greater improvement in the median central foveal thickness, compared to the older group.OCTA revealed interlacing or disorganized pattern at the level of the outer retinal layer in 12 subjects with myopic CNV. After 3 months of treatment, both groups displayed a decrease in the size of the selected CNV area and flow area. The interlacing group displayed a trend towards better anatomical improvements.ConclusionIntravitreal aflibercept injection provides long-term improvement in visual acuity in patients with myopic CNV. Eyes with the interlacing pattern on OCTA displayed a greater decrease in size and flow after aflibercept injection.Trial registrationBefore data collection, written informed consent was obtained from each participant, whose identity information was protected by encryption and conversion to a non-identifiable format and removing data links. This study was approved by the Institutional Review Board of Kaohsiung Veterans General Hospital (KSVGH21-CT1–17).

Flow pattern and perforating vessels in three different phases of myopic choroidal neovascularization seen by swept-source optical coherence tomography angiography.

To compare the choroidal neovascularization (CNV) flow patterns and the relationship between perforating vessels (PVs) and CNV in the three different stages of networks in myopic CNV (mCNV) using swept-source optical coherence tomography angiography (SS-OCTA). This retrospective study included 28 eyes with mCNV that was divided into three phases (active, scar, and atrophic) and observed by SS-OCTA. SS-OCTA findings, with special focus on the relationship between the PVs and CNV, were compared among the three phases. Overall, the CNV signal was detected in 31 of the 34 areas of CNV (91%); in the active, scar, and atrophic phases, respectively, CNV signals were detected in eight of eight areas of CNV (100%), 10 of 11 areas of CNV (91%), and 13 of 15 areas of CNV (86%). Two signal patterns were observed in each phase, i.e., dense and loop; in the atrophic phase, seven eyes were unclassifiable. The ratio between the dense and loop patterns did not differ significantly among the phases. In 30 of 34 areas of CNV for which clear images were obtained, the PVs and CNV were connected directly or indirectly in 19 area of CNV, and in five areas of CNV, trunk-like vessels were connected to the PVs within the CNV. The numbers of foveal or parafoveal CNVs accompanied by PVs were significantly (p=0.0048) greater than those of the extrafoveal CNV. OCTA provides detailed observation of mCNV and the relationship between CNV and PVs. Although the CNV signal pattern does not differ depending on the degree of atrophy, there are cases in which only the trunk-like vessels connect to the PVs within the CNV in the atrophic phase without CNV flow signal.

Assessment of three successive treatments of ranibizumab on neovascular macular degeneration by OCT angiography.

In the present study, the efficacy of three consecutive anti-VEGF treatments in patients with neovascular macular degeneration (nAMD) was assessed by optical coherence tomography angiography (OCT-A). A total of 23 eyes with nAMD were treated with intravitreal injections (IVIs) of ranibizumab once a month for three consecutive months. There were eight follow-up time-points: Prior to the initial IVI and on days 1, 3, 7, 14, 30, 60 and 90 after the first IVI. The follow-up examinations consisted of measurements of the best-corrected visual acuity (BCVA), the height of retinal pigmented epithelium detachment (RPED), the greatest linear dimension (GLD), choroidal neovascularization (CNV) flow area, whole retinal thickness and four-quadrant retinal thickness. The results indicated that, when compared with the baseline, the BCVA gradually improved after IVI and improved significantly on days 60 and 90 (P<0.05); the RPED and GLD improved after IVI, with a significant improvement on days 30, 60 and 90 (all, P<0.05); the CNV flow area was gradually shortened in the early stage after IVI but rebounded on day 30, while the difference was statistically significant on day 14 (P<0.05). The temporal retinal thickness was statistically significant on day 30 (P<0.05) and there were statistically significant differences in nasal and inferior retinal thickness on days 14 and 30 compared with prior to IVI (all, P<0.05). The BCVA was positively correlated with the RPED, GLD, CNV flow area and nasal retinal thickness (all, P<0.05). In conclusion, OCT-A may provide an effective reference to guide the evaluation, treatment and monitoring of nAMD. The present study was registered in the Chinese Clinical Trial Registry (CChiTR; no. ChiCTR1900023607; http://www.chictr.org.cn/listbycreater.aspx).

Influence of CNV vascular morphology in exudative age-related macular degeneration on development of visual acuity and need for anti-VEGF therapy after 1 year

The aim of this pilot study was to investigate vascular morphological characteristics of choroidal neovascularization (CNV) at the time of the initial diagnosis of exudative age-related macular degeneration (nAMD), which enable a prognosis for the development of visual acuity and the necessity for treatment in the first year. In 57patients with the initial diagnosis of nAMD, CNV was detected by optical coherence tomography angiography (OCT-A) and an automated quantitative vessel analysis was performed with respect to area, total vessel length, flow value and average vessel caliber of the CNV. After 12months patients were divided into 2 groups based on visual acuity (visual loss vs. visual gain) and necessity of anti-VEGF therapy (<7 intravitreal injections, IVOM vs. ≥7 IVOM). The mean CNV area was 0.95 mm2 ± 1.07 mm2 (group visual loss 1.56 mm2 ± 1.54 mm2; group visual gain 0.65 mm2 ± 0.53 mm2; p = 0.002/<7 IVOM 1.05 mm2 ± 1.40 mm2; ≥7 IVOM 0.98 mm2 ± 0.94 mm2, p = 0.60). The average total vessel length of the CNV was 9.84 mm ± 11.35 mm (visual loss 16.00 mm ± 16.58 mm; visual gain 6.74 mm ± 5.42 mm; p < 0.003/<7 IVOM 11.21 mm ± 15.10; ≥7 IVOM 9.90 mm ± 9.68 mm; p = 0.68). The mean flow value of the CNV was 0.40 ± 0.06 (visual loss 0.37 ± 0.04; visual gain 0.41 ± 0.07; p = 0.004/<7 IVOM 0.42 ± 0.08; ≥7 IVOM 0.38 ± 0.06; p = 0.02). The average vessel caliber was 28.86 µm ± 2.93 µm (visual loss 28.39 µm ± 2.97 mm; visual gain 29.32 µm ± 3.05 µm; p = 0.24/<7 IVOM 30.26 µm ± 3.49 µm; ≥7 IVOM 28.23 µm ± 2.25 µm; p = 0.02). The results show that amathematical quantification of the CNV in nAMD is possible using OCT‑A. This analysis confirmed again that the size of the CNV (area and total vessel length) is decisive for the prognosis of visual acuity. It also shows that alarger flow value as asign of awell-differentiated CNV is associated with abetter functional prognosis. The number of IVOMs required, however, depends primarily on the composition of the CNV (flow value and vascular caliber). More precise imaging and larger examination cohorts could possibly reveal further relevant biomarkers.

APPLICATION OF OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY TO ASSESS ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY IN MYOPIC CHOROIDAL NEOVASCULARIZATION.

Using optical coherence tomography (OCT) angiography to assess the therapeutic effect of intravitreal anti-vascular endothelial growth factor on myopic choroidal neovascularization (CNV) by detecting the changes of shape, size, and flow area. Our prospective case series recruited consecutive patients with myopic CNV from January 2016 to August 2016. Intravitreal injections of ranibizumab were conducted on all patients. Patients received OCT angiography on 3 different follow-ups, including before treatment, 1 week after treatment, and 1 month after treatment. At each visit, we measured the best-corrected visual acuity, central macular thickness , greatest linear dimension of CNV, selected CNV area and flow area using OCT angiography. This study involved 13 eyes of 12 patients, in which 9 eyes were of 9 women and 4 eyes were of 3 men, with mean age of 49.92 ± 14.79 years. Best-corrected visual acuity was significantly improved with decreased central macular thickness, greatest linear dimension, intraretinal fluid, or subretinal fluid 7 days or 30 days after treatment (All P < 0.05). Myopic CNV was presented as irregular or nearly round closed mass at the level of the outer retinal layer in all eyes at the initial visit. Thirty days after treatment, the size of selected CNV area and flow area were further decreased (t = 4.012, P = 0.003). Combined with OCT B-scan, OCT angiography, a new technique, could provide sensitive and intuitive images and quantitative analysis for monitoring and evaluating the therapeutic effect of intravitreal anti-vascular endothelial growth factor for myopic CNV.

Quantitative Vascular Density Changes in Choriocapillaris Around CNV After Anti-VEGF Treatment: Dark Halo.

The authors have observed and quantified choriocapillaris vascular density changes ("dark halo") around choroidal neovascularization (CNV) before and after anti-vascular endothelium growth factor (VEGF) injections by optical coherence tomography angiography (OCTA). Forty-three flow density areas of 11 eyes with CNV were evaluated before and after treatment in this observational case series. Four cases were CNV type 1 and seven were CNV type 2. All the patients were evaluated by a spectral-domain OCT system. The scans were registered at baseline before injection, between 6 days and 14 days after injection, and monthly thereafter. The dark halo was automated assessed by Image J software. The authors observed a fluctuation of the dark halo around the CNV, the dark halo being larger in 95.4% of the cases before treatment and decreasing after injection. Correspondingly, the mean CNV area decreased in 83.7% of the cases after injection. The mean CNV area before treatment was 0.44 mm2 (± 0.40 mm2) and 0.34 mm2 (± 0.29 mm2) after treatment. The dark halo mean area before treatment was 0.34 mm2 (± 0.27 mm2) and 0.25 mm2 (± 0.23 mm2) after treatment. CNV area and dark halo area reductions after injection were statistically significant (P < .001). CNV-to-halo ratio was statistically significant, decreasing after injection (P < .001). OCTA is a noninvasive vascular imaging tool able to detect CNV flow and features. OCTA is also suitable to highlight choriocapillaris vascular density changes around neovascularization after treatment. The dark halo around CNV seen by OCTA showed a fluctuation after anti-VEGF treatment. These results might be useful in clinical practice. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:918-924.].

Volume-Rendered Projection-Resolved OCT Angiography: 3D Lesion Complexity Is Associated With Therapy Response in Wet Age-Related Macular Degeneration.

PurposeTo explore whether quantitative three-dimensional (3D) analysis of choroidal neovascularization (CNV) using projection-resolved optical coherence tomography angiography (PR-OCTA) is associated with treatment response in neovascular age-related macular degeneration (nAMD).MethodsRetrospective, cross-sectional study of 51 eyes of 49 patients undergoing individualized anti-VEGF therapy for nAMD. Patients were classified as “good” or “poor” responders, requiring injections at less or more frequently than 6-week intervals, respectively. Cross-sectional PR-OCTA images were used to measure the distance between Bruch's membrane and highest CNV flow signal. The number of flow layers within the CNV and the distance between these flow layers (CNV flow thickness) were also analyzed. Two masked, independent graders measured the PR-OCTA parameters. We used 3D volume-rendered PR-OCTA to confirm the number of CNV flow layers and further evaluate CNV complexity.ResultsPoor responders had significantly greater distance between Bruch's membrane and highest CNV flow signal (P < 0.01), greater number of CNV flow layers (P = 0.022), and greater CNV flow thickness (P < 0.01). Volume-rendered PR-OCTA images confirmed the number of CNV flow layers.ConclusionsCross-sectional and 3D volume-rendered PR-OCTA provides a novel approach for quantifying CNV complexity. Our results suggest that CNV acquiring more complex 3D vascular structure are associated with more frequent long-term anti-VEGF therapy, reflecting a particular pattern of normalization or complex CNV remodeling process that characterizes these less responsive eyes.

Quantitative Optical Coherence Tomography Angiography of Choroidal Neovascularization in Age-Related Macular Degeneration

To detect and quantify choroidal neovascularization (CNV) in patients with age-related macular degeneration (AMD) using optical coherence tomography (OCT) angiography. Observational, cross-sectional study. A total of 5 normal subjects and 5 subjects with neovascular AMD were included. A total of 5 eyes with neovascular AMD and 5 normal age-matched controls were scanned by a high-speed (100 000 A-scans/seconds) 1050-nm wavelength swept-source OCT. The macular angiography scan covered a 3 × 3-mm area and comprised 200 × 200 × 8 A-scans acquired in 3.5 seconds. Flow was detected using the split-spectrum amplitude-decorrelation angiography (SSADA) algorithm. Motion artifacts were removed by 3-dimensional (3D) orthogonal registration and merging of 4 scans. The 3D angiography was segmented into 3 layers: inner retina (to show retinal vasculature), outer retina (to identify CNV), and choroid. En face maximum projection was used to obtain 2-dimensional angiograms from the 3 layers. The CNV area and flow index were computed from the en face OCT angiogram of the outer retinal layer. Flow (decorrelation) and structural data were combined in composite color angiograms for both en face and cross-sectional views. The CNV angiogram, CNV area, and CNV flow index. En face OCT angiograms of CNV showed sizes and locations that were confirmed by fluorescein angiography (FA). Optical coherence tomography angiography provided more distinct vascular network patterns that were less obscured by subretinal hemorrhage. The en face angiograms also showed areas of reduced choroidal flow adjacent to the CNV in all cases and significantly reduced retinal flow in 1 case. Cross-sectional angiograms were used to visualize CNV location relative to the retinal pigment epithelium and Bruch's layer and classify type I and type II CNV. A feeder vessel could be identified in 1 case. Higher flow indexes were associated with larger CNV and type II CNV. Optical coherence tomography angiography provides depth-resolved information and detailed images of CNV in neovascular AMD. Quantitative information regarding CNV flow and area can be obtained. Further studies are needed to assess the role of quantitative OCT angiography in the evaluation and treatment of neovascular AMD.