Evaluation of Posterior Ocular Blood Flow in Diabetic Retinopathy Patients Without Macular Edema Using Optical Coherence Tomography Angiography.

AIM: The objective of this study is to investigate and compare the superficial and deep vascular structures of the retina, as well as the changes in the choriocapillaris (CC) and optic disc microvasculature, using optical coherence tomography angiography (OCTA) in patients diagnosed with diabetes mellitus (DM) without diabetic retinopathy (DR), patients with non-proliferative and proliferative DR, and healthy individuals. MATERIALS AND METHODS: This prospective study conducted between July 2020 and July 2021 included patients diagnosed with type 2 DM without DR, as well as patients with mild nonproliferative, moderate nonproliferative, and proliferative DR without macular oedema. A control group of 25 age- and gender-matched healthy individuals was also included. OCTA parameters of the patients were examined. RESULTS: In the DR groups, compared to the control group, there was a significant decrease in macular superficial, deep, and CC perfusion areas as the severity of DR increased (p<0.001). The vascular density (VD) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) exhibited a statistically significant decrease in all quadrants of the DR group compared to the control group (p = 0.033 for SCP in the fovea, p<0.001 for all other quadrants). The superficial and deep FAZs showed a significant expansion in the DR group compared to the control group (p = 0.003 for superficial FAZ, p<0.001 for deep FAZ). As the severity of DR increased, there was a statistically significant decrease in the perfusion areas of the optic nerve head (ONH), radial peripapillary capillary (RPC), and vitreous segments (p<0.001 for ONH, p = 0.031 for RPC, p<0.001 for vitreous). There was a statistically significant decrease in RPC VD in all quadrants as the severity of DR increased. Moreover, as the severity of DR increased, a statistically significant decrease in the VD of the ONH was observed in all quadrants except for the inferior nasal (p = 0.094), inferior temporal (p = 0.111), superior temporal (p = 0.18), and temporal (p = 0.284) quadrants. CONCLUSION: Our study demonstrated the involvement of macular and optic nerve perfusion areas (PA) and VD in diabetic patients. OCTA proved to be a valuable and noninvasive imaging modality, providing an easy and repeatable assessment of posterior segment vascular changes in patients with DR.

Investigation of Choroidal Blood Flow and Thickness Changes Induced by Near Work in Young Adults.

PURPOSE: This research aimed to determine the effects of near work on macular choroidal blood flow and thickness in young adults. METHODS: A total of 109 participants (19-28 years old) were recruited from Capital Medical University in China. The participants spent 40 min reading a book text at a distance of 33 cm. Swept-source optical coherence tomography/optical coherence tomography angiography (SS-OCT/OCTA) was performed to measure the changes in choriocapillaris perfusion area (CCPA) and choroidal thickness (ChT) after 40 min of near work. The SS-OCT/OCTA data covered an area of 6 mm × 6 mm, which centered on the fovea. RESULTS: The baseline ChT and CCPA before near work were negatively correlated with AL, while positively correlated with the magnitude of spherical equivalent (p < .001). Total CCPA decreased significantly by 6 mm × 6 mm macular area after near work compared to that before near work (24.26 ± 1.96 vs. 24.63 ± 1.61 mm2, p<.001). The macular ChT was lower after 40 min of reading than that before 40 min of reading, but no significant difference was observed (302.25 ± 77.69 vs. 304.92 ± 79.73 µm, p = .078). The extent of choroidal thinning was significantly positively correlated with the magnitude of CCPA reduction (p < .001). The decline in CCPA after near work was significantly positively correlated with axial length (AL; p < .001). CONCLUSION: This study demonstrated that near work significantly decreased CCPA. The extent of CCPA reduction after near work was associated with higher severity of myopia and choroidal thinning. The baseline CCPA and ChT decreased gradually with AL.

[Application of Three-dimensional Computed Tomography Bronchography and 
Angiography Combined with Perfusion Area Identification Technique 
in Uniport Thoracoscopic Complex Segmentectomy].

BACKGROUND: With the extensive application of segmental lung resection in the treatment of early-stage lung cancer, how to complete segmentectomy more accurately and minimally invasively has become a research hotspot. The aim of this study is to explore the application of three-dimensional computed tomography bronchography and angiography (3D-CTBA) combined with perfusion area recognition technique in single-hole thoracoscopic complex segmentectomy. METHODS: From January 2021 to January 2022, the clinical data of 112 consecutive patients undergoing single-port thoracoscopic complex segmentectomy in the Department of Thoracic Surgery, Xuanwu Hospital, Capital Medical University were retrospectively analyzed. The three-dimensional reconstruction combined with perfusion area identification technique was used to perform the operation and the clinical data were analyzed. RESULTS: The average operation time was (141.1±35.4) min; the initial time of intersegmental plane display was (12.5±1.7) s; the maintenance time of intersegmental plane was (114.3±10.9) s; the intersegmental plane was clearly displayed (100%); the amount of bleeding was [10 (10, 20)] mL; the total postoperative drainage volume was (380.5±139.7) mL; the postoperative extubation time was (3.9±1.2) d; and the postoperative hospitalization time was (5.2±1.6) d. Postoperative complications occurred in 8 cases. CONCLUSIONS: The advantages of 3D-CTBA combined with perfusion area recognition technique are fast, accurate and safe in identifying intersegmental boundary in single-port thoracoscopic complex segmentectomy, which could provide guidances for accuratding resection of tumors, shortening operation time and reducing surgical complications.

Application of Three-dimensional Computed Tomography Bronchography and Angiography Combined with Perfusion Area Identification Technique in Uniport Thoracoscopic Complex Segmentectomy / 中国肺癌杂志

BACKGROUND@#With the extensive application of segmental lung resection in the treatment of early-stage lung cancer, how to complete segmentectomy more accurately and minimally invasively has become a research hotspot. The aim of this study is to explore the application of three-dimensional computed tomography bronchography and angiography (3D-CTBA) combined with perfusion area recognition technique in single-hole thoracoscopic complex segmentectomy.@*METHODS@#From January 2021 to January 2022, the clinical data of 112 consecutive patients undergoing single-port thoracoscopic complex segmentectomy in the Department of Thoracic Surgery, Xuanwu Hospital, Capital Medical University were retrospectively analyzed. The three-dimensional reconstruction combined with perfusion area identification technique was used to perform the operation and the clinical data were analyzed.@*RESULTS@#The average operation time was (141.1±35.4) min; the initial time of intersegmental plane display was (12.5±1.7) s; the maintenance time of intersegmental plane was (114.3±10.9) s; the intersegmental plane was clearly displayed (100%); the amount of bleeding was [10 (10, 20)] mL; the total postoperative drainage volume was (380.5±139.7) mL; the postoperative extubation time was (3.9±1.2) d; and the postoperative hospitalization time was (5.2±1.6) d. Postoperative complications occurred in 8 cases.@*CONCLUSIONS@#The advantages of 3D-CTBA combined with perfusion area recognition technique are fast, accurate and safe in identifying intersegmental boundary in single-port thoracoscopic complex segmentectomy, which could provide guidances for accuratding resection of tumors, shortening operation time and reducing surgical complications.

Wide-field swept-source OCTA in the assessment of retinal microvasculature in early-stage diabetic retinopathy.

BACKGROUND: To perform a quantitative analysis of retinal microvasculature in patients with early-stage diabetic retinopathy (DR) using wide-field swept-source optical coherence tomography angiography (SS-OCTA).  METHODS: One hundred nineteen eyes of 119 patents (67 eyes with no DR and 52 eyes with mild-moderate nonproliferative diabetic retinopathy (NPDR)) were enrolled in this observational and cross-sectional cohort study, and an age-matched group consisting of 39 eyes of 39 non-diabetic subjects were set as the control. Each participant underwent a full ophthalmic examination, including wide-field SS-OCTA imaging. On OCTA scans (12 mm * 12 mm), the mean perfusion area (PA) and vessel density (VD) were independently measured in all 16 Early Treatment Diabetic Retinopathy Study (ETDRS) sectors. Linear regression analyses were conducted to evaluate the influences of PA. RESULTS: In the central ring, there were no significant differences in the average PA and VD among the groups. In the 3 mm radius, the PA and VD of the no DR and mild-moderate NPDR were significantly decreased compared with the control group in superior and inferior quadrants. In the wide-field scans (9 and 12 mm radius), there was no significant difference in average PA and VD between the groups in each sectors (p > 0.05). Regression analysis found that the effect of VD on PA was statistically different (b = 1.311, p < 0.001). CONCLUSION: Wide-field OCTA imaging is useful for evaluating peripheral capillary perfusion in eyes with early-stage DR. Decrease in PA and VD was greater in the S3 and I3 sectors, and reductions in PA and VD were uneven in wide-filed sectors (9 and 12 mm radius).

Anti-VEGF reduces inflammatory features in macular edema secondary to retinal vein occlusion.

AIM: To investigate the anti-inflammatory effect of intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) in patients with macular edema secondary to retinal vein occlusion (RVO-ME). METHODS: Twenty-eight eyes from twenty-eight treatment-naïve patients (14 males and 14 females) with RVO-ME were included in this retrospective study. The retinal vein occlusion (RVO) was comprised of both central retinal vein occlusion (CRVO, n=14) and branch retinal vein occlusion (BRVO, n=14). Intravitreal injection of anti-VEGF reagents were administered monthly for three consecutive months, in which 18 patients were injected with ranibizumab and 10 patients were injected with conbercept. All eyes were imaged with optical coherence tomography angiography (OCTA) at baseline and 1wk after monthly intravitreal anti-VEGF injection. The visual acuity (VA), central macular thickness (CMT), the number of hyperreflective foci (HRF) recognized as an inflammatory sign in OCT images, and non-perfusion area (NPA), were compared before and after anti-VEGF treatments. RESULTS: The mean interval between baseline and follow-up was 29.4±0.79 (range, 27-48)d. Compared with the baseline, the VA improved (logMAR 1.5±0.1 vs 0.8±0.1, P<0.05) and CMT decreased (460±34.0 µm vs 268.8±12.0 µm, P<0.05), significantly, after anti-VEGF treatment. The number of HRF was decreased significantly (76.5±4.8 vs 47.8±4.3, P<0.05) after anti-VEGF treatment. CONCLUSION: Anti-VEGF therapy is effective in treating RVO-ME. The mechanisms for the decreased HRF and the reduction of NPA by anti-VEGF therapy merits further exploration.

Deep Learning Models for Segmenting Non-perfusion Area of Color Fundus Photographs in Patients With Branch Retinal Vein Occlusion.

Purpose: To develop artificial intelligence (AI)-based deep learning (DL) models for automatically detecting the ischemia type and the non-perfusion area (NPA) from color fundus photographs (CFPs) of patients with branch retinal vein occlusion (BRVO). Methods: This was a retrospective analysis of 274 CFPs from patients diagnosed with BRVO. All DL models were trained using a deep convolutional neural network (CNN) based on 45 degree CFPs covering the fovea and the optic disk. We first trained a DL algorithm to identify BRVO patients with or without the necessity of retinal photocoagulation from 219 CFPs and validated the algorithm on 55 CFPs. Next, we trained another DL algorithm to segment NPA from 104 CFPs and validated it on 29 CFPs, in which the NPA was manually delineated by 3 experienced ophthalmologists according to fundus fluorescein angiography. Both DL models have been cross-validated 5-fold. The recall, precision, accuracy, and area under the curve (AUC) were used to evaluate the DL models in comparison with three types of independent ophthalmologists of different seniority. Results: In the first DL model, the recall, precision, accuracy, and area under the curve (AUC) were 0.75 ± 0.08, 0.80 ± 0.07, 0.79 ± 0.02, and 0.82 ± 0.03, respectively, for predicting the necessity of laser photocoagulation for BRVO CFPs. The second DL model was able to segment NPA in CFPs of BRVO with an AUC of 0.96 ± 0.02. The recall, precision, and accuracy for segmenting NPA was 0.74 ± 0.05, 0.87 ± 0.02, and 0.89 ± 0.02, respectively. The performance of the second DL model was nearly comparable with the senior doctors and significantly better than the residents. Conclusion: These results indicate that the DL models can directly identify and segment retinal NPA from the CFPs of patients with BRVO, which can further guide laser photocoagulation. Further research is needed to identify NPA of the peripheral retina in BRVO, or other diseases, such as diabetic retinopathy.

Effect of caffeine on superficial retinal vasculature of the macula in high myopes using optical coherence tomography angiography – A pilot study

Purpose: To monitor effect of caffeine on vasculature of the inner retina of high myopesMethods: This was a crossover, self‐control, randomized trial. Healthy young high myopes were recruited to take 200 mg of caffeine capsule and placebo capsule, randomly assigned in two visits separated by at least one week. Superficial retinal vasculature in terms of vessel length density (VD) and perfusion area density (PD) was captured and monitored using a spectral domain optical coherence tomography angiography (OCTA) machine. After baseline measurements, blood pressure (BP), intraocular pressure (IOP), and subfoveal choroidal thickness (ChT) were also monitored at 30‐min intervals till 3 h.Results: Eighteen subjects (6 male, 24.3 ± 3.1 years) completed the study. After taking the caffeine capsule, there was a significant increase in BP (p < 0.01), and reduction in ChT (p < 0.01), with no change in IOP (p = 0.36). VD demonstrated a trend of reduction at the central 1‐mm circle, and 1‐3 mm annulus (p < 0.01) following the ETDRS grid. Reduction trend of PD appeared at the central 1‐mm circle, 1‐3 mm annulus, and the entire 3‐mm circle (p < 0.01). Compared with baseline, VD and PD reductions were significant 180 min after taking the caffeine capsule at the central 1‐mm circle, but the reduction was small (VD: by 1mm-1; PD: by 1%). Changes in other regions were not significant.Conclusions: The current study found significant reduction in VD and PD after taking 200 mg of caffeine capsule. Such a small amount of alteration may be clinically irrelevant. (AU)

Nonperfusion Area and Other Vascular Metrics by Wider Field Swept-Source OCT Angiography as Biomarkers of Diabetic Retinopathy Severity.

Purpose: To study the wider field swept-source optical coherence tomography angiography (WF SS-OCTA) metrics, especially non-perfusion area (NPA), in the diagnosing and staging of DR. Design: Cross-sectional observational study (November 2018-September 2020). Participants: 473 eyes of 286 patients (69 eyes of 49 control patients and 404 eyes of 237 diabetic patients). Methods: We imaged using 6mm×6mm and 12mm×12mm angiograms on WF SS-OCTA. Images were analyzed using the ARI Network and FIJI ImageJ. Mixed effects multiple regression models and receiver operator characteristic analysis was used for statistical analyses. Main Outcome Measures: Quantitative metrics such as vessel density (VD); vessel skeletonized density (VSD); foveal avascular zone (FAZ) area, circularity, and perimeter; and NPA in DR and their relative performance for its diagnosis and grading. Results: Among patients with diabetes (median age 59 years), 51 eyes had no DR, 185 eyes (88 mild, 97 moderate-severe) had non-proliferative DR (NPDR); and 168 eyes had proliferative DR (PDR). Trend analysis revealed a progressive decline in superficial capillary plexus (SCP) VD and VSD, and increased NPA with increasing DR severity. Additionally, there was a significant reduction in deep capillary plexus (DCP) VD and VSD in early DR (mild NPDR), but the progressive reduction in advanced DR stages was not significant. NPA was the best parameter to diagnose DR (AUC:0.96), whereas all parameters combined on both angiograms efficiently diagnosed (AUC:0.97) and differentiated between DR stages (AUC range:0.83-0.97). The presence of diabetic macular edema was associated with reduced SCP and DCP VD and VSD within mild NPDR eyes, whereas an increased VD and VSD in SCP among moderate-severe NPDR group. Conclusions: Our work highlights the importance of NPA, which can be more readily and easily measured with WF SS-OCTA compared to fluorescein angiography. It is additionally quick and non-invasive, and hence can be an important adjunct for DR diagnosis and management. In our study, a combination of all OCTA metrics on both 6mm×6mm and 12mm×12mm angiograms had the best diagnostic accuracy for DR and its severity. Further longitudinal studies are needed to assess NPA as a biomarker for progression or regression of DR severity.

Effect of caffeine on superficial retinal vasculature of the macula in high myopes using optical coherence tomography angiography - A pilot study.

PURPOSE: To monitor effect of caffeine on vasculature of the inner retina of high myopes METHODS: This was a crossover, self-control, randomized trial. Healthy young high myopes were recruited to take 200 mg of caffeine capsule and placebo capsule, randomly assigned in two visits separated by at least one week. Superficial retinal vasculature in terms of vessel length density (VD) and perfusion area density (PD) was captured and monitored using a spectral domain optical coherence tomography angiography (OCTA) machine. After baseline measurements, blood pressure (BP), intraocular pressure (IOP), and subfoveal choroidal thickness (ChT) were also monitored at 30-min intervals till 3 h. RESULTS: Eighteen subjects (6 male, 24.3 ± 3.1 years) completed the study. After taking the caffeine capsule, there was a significant increase in BP (p < 0.01), and reduction in ChT (p < 0.01), with no change in IOP (p = 0.36). VD demonstrated a trend of reduction at the central 1-mm circle, and 1-3 mm annulus (p < 0.01) following the ETDRS grid. Reduction trend of PD appeared at the central 1-mm circle, 1-3 mm annulus, and the entire 3-mm circle (p < 0.01). Compared with baseline, VD and PD reductions were significant 180 min after taking the caffeine capsule at the central 1-mm circle, but the reduction was small (VD: by 1mm-1; PD: by 1%). Changes in other regions were not significant. CONCLUSIONS: The current study found significant reduction in VD and PD after taking 200 mg of caffeine capsule. Such a small amount of alteration may be clinically irrelevant.

Non-Perfusion Area Index for Prognostic Prediction in Diabetic Retinopathy.

Fundus fluorescent angiography is a standard examination in Japan that can directly visualize the circulatory failure in diabetic retinopathy but is not used in Western countries. In this study, we examine the relationship between the non-perfusion area in fundus fluorescent angiography and the progression of diabetic retinopathy. We evaluated 22 eyes between 22 patients who had their first fundus fluorescent angiography during a clinical episode at Keio University Hospital from January 2012 to May 2015, were diagnosed as having preproliferative diabetic retinopathy, and could be followed for at least three years. The non-perfusion area index (%) in nine segmented fundi in the initial fundus fluorescent angiography was calculated, and the progression to proliferative diabetic retinopathy over three years was evaluated. Three out of the 22 eyes (13.6%) developed proliferative diabetic retinopathy over three years. The non-perfusion area index for the initial fundus fluorescent angiography was significantly associated with progression to proliferative diabetic retinopathy. The non-perfusion area index in the posterior pole was most strongly correlated with the progression to proliferative diabetic retinopathy. Thus, the non-perfusion area index in the posterior pole among those with preproliferative diabetic retinopathy may predict the progression to proliferative diabetic retinopathy in the subsequent three years.

Sensitivity and Specificity of the Optical Coherence Tomography Angiography for Detection of Neovascularization and Evaluation of Peripheral Ischemia in Diabetic Retinopathy.

Objectives: The purpose of this study was to identify the sensitivity and specificity of optical coherence tomography angiography (OCTA) parameters for the presence of neovascularization elsewhere (NVE) and to investigate the relationship between ischemic areas. Methods: This study included 59 eyes with non-proliferative diabetic retinopathy (NPDR) and 36 eyes with proliferative diabetic retinopathy (PDR). The foveal avascular zone (FAZ), vessel density (VD) for the superficial and the deep capillary plexus (DCP), choriocapillaris flow area (CCP), and non-perfusion area (unit²) were recorded. The area under the curve (AUC) under the receiver operating characteristic curves, sensitivity and specificity were calculated for statistically significant outcomes. Later, based on visual acuity, PDR group was subdivided into group 2A: PDR eyes with VA ≤0.2 logMAR and group 2B: PDR eyes with VA>0.2 logMAR. Non-perfusion area and OCTA features were compared between the subgroups. Results: The VD in DCP was significantly lower, FAZ and non-perfusion area were larger in PDR group (p=0.001, p<0.001, and p<0.001). The AUC for presence of NVE, for the VD, was 0.710 (p=0.012) with sensitivity and specificity of 64% and 65%, for the FAZ was 0.746 (p<0.001) with sensitivity and specificity of 72% and 72.7%. There was a significant positive correlation between the FAZ and non-perfusion area (For NPDR, p=0.025, for PDR p<0.001). There was a significant negative correlation between the VD in DCP and ischemic area in PDR group. (p<0.001) In group 2B, non-perfusion area and FAZ were larger than group 2A. The VD and CCP flow area were also lower in group 2B (All, p<0.05). Conclusion: In cases with decreased VD in DCP and increased FAZ, the probability of PDR increases. Despite the sensitivity and specificity of the OCTA indices for the prediction of NVE being moderate, the OCTA is very useful in evaluating the microvascular structure in DR.

Utility of the Virtual Liver Parenchymal Perfusion Area Using a Commercially Available Workstation in Transarterial Chemoembolization for Hepatocellular Carcinoma.

PURPOSE: To evaluate the accuracy of the virtual liver parenchymal perfusion area using a commercially available workstation and liver analysis software in conventional transarterial chemoembolization (cTACE) for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This method was retrospectively applied to 29 treated HCCs in 23 patients. The virtual embolic area (VEA) was estimated based on cone beam computed tomography during hepatic arteriography using a commercially available workstation and liver analysis software by two observer groups (group A: experts; group B: semi-experts). The real embolic area (REA) was defined as the area where iodized oil accumulated on computed tomography at 1 week after cTACE. The REA was estimated by each of the two groups, and the mean REA between the groups (mREA) was used as a standard reference. Agreement of volume and cross-sectional area in three orthogonal planes between the VEA and mREA were analyzed using intraclass correlation coefficients (ICCs) and Bland-Altman plots. RESULTS: The ICCs for volume between VEA and mREA were 0.97 and 0.88 for groups A and B, respectively, and those for cross-sectional area were 0.94 and 0.88 for the axial plane, 0.95 and 0.83 for the coronal plane, and 0.87 and 0.74 for the sagittal plane, respectively. Thus, the overall agreement was excellent, except for the sagittal imaging plane in group B. CONCLUSION: This method using a commercially available workstation and liver analysis software can be useful for estimating the embolic area in cTACE.

Automatic measurement of global retinal circulation in fluorescein angiography.

Examination of the retinal circulation in patients with retinal diseases is a clinical routine for ophthalmologists. In the present work, an automatic method is proposed for measuring the global retinal circulation in fluorescein angiography (FA). First, the perfusion region in FA images is segmented using a multiscale line detector. Then, the time evolution of the perfusion area is modeled using damped least-squares regression. Based on the perfusion area profile, some circulation parameters are defined to describe quantitatively the global retinal circulation. The effectiveness of the proposed method is tested using our own and public datasets, with reasonable results and satisfactory accuracy compared with manual measurement. The proposed method has good computing efficiency and thus has potential to be used in clinical practice for evaluation of global retinal circulation.

Inhibitory Effects On Retinal Neovascularization by Ranibizumab and sTie2-Fc in An Oxygen-Induced Retinopathy Mouse Model.

PURPOSE: To study retinal neovascularization (RNV) inhibition by intravitreal injections (IVs) of ranibizumab, sTie2 fusion protein (sTie2-Fc), and a combined therapy in an oxygen-induced retinopathy (OIR) model. MATERIALS AND METHODS: An OIR mouse model was used to simulate RNV in retinopathy of prematurity (ROP); and the effect of blocking the angiopoietin (Ang) and its receptor (Tie2) and the vascular endothelial growth factor (VEGF) and its receptor (VEGFR) signaling pathways was compared using an IV of sTie2-Fc (Ang inhibitor) and/or ranibizumab (aVEGF antagonist). The effects were assessed using fluorescein isothiocyanate (FITC)-dextran cardiac perfusion, isolectin B4 (IB4) staining with whole retinal mounting, and hematoxylin and eosin (HE) staining to count the endothelial cells (ECs) that broke through the internal limiting membrane (ILM). The mRNA and protein levels of VEGF-A, VEGFR-2, Ang1, Ang2, and Tie2 were also determined by reverse transcriptase polymerase chain reaction (RT-PCR) and western blot analysis. RESULTS: Compared with the control group injected with phosphate-buffered saline (PBS), all three experimental groups, ranibizumab, sTie2-Fc, and ranibizumab + sTie2-Fc, had a significant decrease in micro-vessel densities and neovascular clusters, and fewer ECs broke through the ILM (all p < 0.05). The non-perfusion areas decreased in both mono-treated groups, although the combined therapy had larger non-perfusion areas. All three treatments decreased the mRNA and protein levels of VEGFA, Ang1, and Tie2. CONCLUSION: In this study, it was confirmed that blocking the Ang/Tie2 and/or VEGF/VEGFR pathways could inhibit RNV and decrease abnormal micro-vessel density; and the mono-blockage of Ang/Tie2 might cause a smaller non-perfusion area.

Comparison between wide-angle OCT angiography and ultra-wide field fluorescein angiography for detecting non-perfusion areas and retinal neovascularization in eyes with diabetic retinopathy.

PURPOSE: To compare the ability of wide-angle optical coherence tomography angiography (OCTA) with that of ultra-wide field fluorescein angiography (UWFFA) to detect non-perfusion areas (NPAs) or retinal neovascularization (NV) in eyes with diabetic retinopathy (DR). METHODS: Patients with DR underwent UWFFA using the Optos® panoramic 200Tx imaging system and wide-angle OCTA with 12 × 12 mm fields of five visual fixations using the PLEX Elite 9000®. We compared the abilities of UWFFA and OCTA to detect NPAs and NV. RESULTS: Fifty-eight eyes of 33 patients (mean age, 60.0 years old; female/male, 16/17) with DR were evaluated. NPAs were detected in 47 out of 58 eyes using UWFFA and in 48 eyes using OCTA. NVs were detected in 25 out of the 58 eyes using UWFFA and in 26 eyes using OCTA. The sensitivity for detection of NPA using OCTA was 0.98, and the specificity was 0.82. The sensitivity for detection of NV was 1.0, and the specificity was 0.97. CONCLUSION: The wide-angle OCTA seems to be clinically useful for the detection of NPAs or NV.

Changes in retinal ischaemic index correlate with recalcitrant macular oedema in retinal vein occlusion: WAVE study.

AIM: To evaluate changes in the ischaemic index (ISI) after targeted retinal photocoagulation (TRP) and to investigate the correlation between these changes and macular oedema (ME). METHOD: Twenty-four eyes of 24 patients with retinal vein occlusion (RVO) with recurrent ME were included. Ultra-widefield fluorescein angiography (UWFFA; Optos 200Tx) was obtained at baseline and every 4 months. The regions of retinal non-perfusion and the total gradable retina were manually segmented on UWFFA images for calculating the global ISI. ISI was also computed for specific regions defined by a standardised grid: perimacular area (PMA), near-peripheral area (NPA), mid-peripheral area (MPA) and far-peripheral area (FPA). Global and regional ISIs and change in ISI over time were correlated with central macular thickness (CMT). RESULTS: The ISIs of entire retina, PMA, NPA, MPA and FPA at baseline were 30.5%±23.3, 17.7%±20.6, 21.9%±19.0, 33.0%±27.9 and 48.0%±32.9, respectively. The ISIs at final follow-up were 23.5%±19.9, 15.7%±22.2, 16.5%±16.7, 24.7%±24.7 and 24.7%±24.7, respectively. A significant correlation was found between CMT and global ISI during follow-up (r=0.22, p=0.03). Among the different retinal zones, PMA showed a correlation with CMT (r=0.27, p=0.007). The change in ISI for the total retina (Δtotal), PMA (ΔPMA) and NPA (ΔNPA) retinal regions was positively correlated with the change in CMT (ΔCMT) (r=0.45, 0.42 and 0.50, respectively, p=0.006, 0.009 and 0.002, respectively). CONCLUSION: The severity of ME was correlated with the ISIs of the entire retina and the PMA. The reduction in ME was correlated with the reduction in ISI of the entire retina as well as the ISIs for the NPA and PMA following TRP. The role of TRP, particularly to these regions (NPA, PMA), warrants further investigation in recalcitrant RVO-associated ME.

Observation of the effect of fundus fluorescein angiography for diabetic retinopathy / 中国基层医药

Objective To observe the effect of fundus fluorescein angiography(FFA)for diabetic retinopathy (DR).Methods FFA results of 85 cases(161 eyes)were retrospectively analyzed.The distribution of DR,the dis-tribution of non -perfusion (NP),the relationship between diabetic maculopathy (DM)and different DR period were studied.Results The ratios of Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,Ⅵ of DR were 14.29%,44.72%,34.78%,3.11%,3.11%.NP was found in 69 eyes in 161 DR eyes.The occurrence of NP was highest (81.26%)in nasal,there was NP difference in the distribution of the different quadrants (χ2 =13.931,P <0.01),there were NP differences at different distances from the optic disc.The occurrence of NP was highest (84.06%)in midperiphera.The incidence rates of macular degeneration in Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,Ⅵ of DR were 8.70%,31.94%,58.93%,80.00%,80.00%.There was correla-tion between DMand DR (χ2 =26.093,P <0.01).Conclusion FFA can provid information for DR severity grad-ing and DM,there were positively correlations between incidence and severity of DM and DR grade,NP was usually occurred at the nasal retina and the midpefipheral retina.

Neovascularization in Branch Retinal Vein Occlusion Combined with Arterial Insufficiency

The aim of this study is to elucidate the association of neovascularization in branch retinal vein occlusion (BRVO) combined with major arterial insufficiency (MAI), compared with BRVO alone. The authors retrospectively reviewed the charts, color photographs, and fluorescein angiograms of 304 patients (308 eyes) who had BRVO from 1990 to 2002 at Hanyang University hospital. Patients with BRVO combined with MAI and patients with BRVO alone were differentiated by angiographic appearance. Of the 308 eyes, 12 (3.9%) had neovascularization, all of which were in the 56 eyes of the MAI group for which the neovascularization rate was 21.4%. Neovascularization in BRVO was more strongly associated with the non-perfusion caused by MAI, rather than with the extent of the non-perfusion area that originated from retinal capillary obstruction. MAI is considered as a risk factor for neovascularization and hence could be a prognostic factor.