Source Optical Coherence Tomography Angiography Research Articles

Non-Neovascular Subretinal Fluid with Serous Retinal Pigment Epithelial Detachment: Wait or Treat

Introduction: To describe the course of subretinal fluid (SRF) in eye with serous pigment epithelial detachment (serous PED) in the absence of macular neovascularization (non-neovascular AMD). Method: This is a retrospective case study included one eye with non-neovascular SRF associated with serous PED. Swept source optical coherence tomography (SS-OCT) and optical coherence angiography (OCTA) were obtained at baseline and follow up with qualitative and quantitative analysis of macula, pigment epithelial detachment (PED), subretinal fluid (SRF) and the presence or absence of macular neovascular membrane (MNV) in addition to other multimodal imaging modalities like fluorescein angiography (FA) and fundus auto fluorescence (FAF). Results: Our 66-year-old female has presented with left serous (PED) with apical (SRF) and no MNV on OCTA with baseline best corrected vision (BCVA) in Log MAR = 0.5. The SS-OCT, OCTA, and BCVA were stable over the initial five-month follow-up observation period with no MNV (non-neovascular SRF). One month later, the patient received an intravitreal anti-VEGF injection outside our clinic. 1-month post-outside clinic anti-VEGF injection, SS-OCT showed a small RPE tear with flattening of RPE detachment and preservation of BCVA =0.5. In the 3rd month post-outside clinic anti-VEGF injection, the SS-OCT showed slight flattening of RPE detachment with an obvious increase in SRF, still negative MNV on the OCTA associated with a drop in BCVA to 0.3. The decision was made to give the patient an initial three loading doses of aflibercept injections .The SS-OCT post 2nd aflibercept injection showed complete resolution and drying out of SRF, with an improvement of BCVA to 0.5. we continue completing the loading phase and then the patient was placed on treat and extend regimen (T&E). After the fifth aflibercept injection, the PED was completely flattened with appearance of MNV on OCTA after resolution of SRF. Conclusion: Many published studies provide preliminary data about non-neovascular AMD with SRF. SRF could be present in the absence of MNV due to RPE decompensation or RPE pump failure. However, the non-neovascular SRF could be transformed with time into a neovascular one with the presence of MNV. Multimodal imaging approach is essential in differentiating non-neovascular versus neovascular SRF and avoiding unnecessary antiVEGF injections.

Swept source optical coherence tomography and optical coherence tomography angiography in central serous chorioretinopathy

Aims/Purpose: To describe swept source optical coherence tomography (SS‐OCT) and SS‐OCT angiography (SS‐OCT‐A) findings in central serous chorioretinopathy (CSCR).Methods: A retrospective study including 20 patients (22eyes) with acute CSCR, 31 patients (44eyes) with chronic CSCR, 35 uneffected fellow eyes and 50 healthy subjects (50 eyes). SS‐OCT was performed for all eyes with quantitative and qualitative analysis. SS‐OCT‐A was practiced for 17 eyes of the acute group, 38 eyes of the chronic group, 29 uneffected fellow eye and all the healthy subjects with quantitative and qualitative assessment.Results: The SS‐OCT revealed a serous retinal detachment in 100% of eyes with acute CRSC and 69% of eyes with chronic CSCR. The Pigment epithelial detachment was present in 9 eyes in the acute group and in 5 eyes in the chronic group. Outer nuclear layer thickness was lower in the chronic group compared to the acute group and the fellow eyes. Three eyes with acute CSCR and 11 eyes with chronic CSCR had alterations in the ellipsoid zone. The interdigitating zone was thickened and regular, granular, defective and atrophic. Macular oedema and hypereflective membrane were only present in chronic CSCR. Other abnormalities were present in both groups such as fibrin, hyperreflective dots and pigment epithelial irregularities. Subfoveal choroidal thickness and Haller's layer thickness were significantly higher in the acute CSCR, chronic CSCR and the fellow eyes than in the control group. The SS‐OCT‐A showed vascular abnormalities and vascular rarefications in superficial (SCP) and deep (DCP) capillary plexus. The vascular densities (VD) of SCP and DCP in chronic CSCR were lower than those in the acute group, fellow eyes and the control group. We objected in the two groups (acute and chronic) hypointense areas, pattern hyperintense and hypointense and a hyperintense neovascular membrane, the later was only found in the chronic CSCR. The VD of choriocapillaris in acute and chronic CSCR were lower compared to fellow eyes and the control group.Conclusions: SS‐OCT shows structural retinal and choroidal changes during the acute and chronic phase of CSCR. The qualitative and quantitative vascular changes attested by SS‐OCT‐A affect not only the choriocapillaris but also the retinal capillary plexuses.

Optical coherence tomography angiography findings after silicone oil tamponade for rhegmatogenous retinal detachment

Aim: To describe retinal structural and microvascular changes using Swept source optical coherence tomography (SS‐OCT) and OCT angiography (OCT‐A) in patients with rhegmatogenous retinal detachment (RRD) treated by vitrectomy (PPV) and silicone oil (SO) tamponade and to identify the final visual acuity (VA) prognostic factors.Methods: In this retrospective study, patients were treated with PPV and SO tamponade for uncomplicated DRR. After SO removal, retinal thickness was assessed by SS‐OCT. The foveal avascular zone (FAZ) area, the fractal dimension (FD), the lacunarity (LAC) and the macular capillary vessel density (VD) in the superficial (PCS) and deep plexuses (PCP) and in the choriocapillaris (CC) were analysed.Results: Thirty‐one eyes were included in this study; 20 eyes (65%) had macula ‘OFF’ RRD. The mean post‐operative final VA was 3.2/10. Outer retinal defect was observed in 74.1% of the operated eyes. Central macular thickness (CMT) and parafoveal thickness were significantly decreased compared with healthy fellow eyes (p = 0.048; p = 0.029). Outer nuclear layer (ONL) and subfoveal choroid were significantly thinned in the operated eyes (p = 0.003; p = 0.017). The FAZ in PCS and PCP and was larger (p = 0.042; p = 0.032), the VD (total, parafoveal and parafoveal) in the PCP were significantly lower (p = 0.004; p = 0.012; p = 0.049) and the lacunarity (LAC) at the PCP level was significantly higher (p = 0.040) in the operated eyes than in the fellow eyes. The final VA was correlated with the defect of the outer retina (p < 0.002) and the VD in PCP (p = 0.0199). The duration of SO tamponade was signifcantly correlated with the outer retinal defect (p = 0.011), the enlargement of FAZ area (p = 0.001) and the VD in DCP (p = 0.002).Conclusion: SIO can lead to structural and vascular retinal ischaemic defect such as enlargement and irregularity of the FAZ and predominant PCP capillary abnormalities. These changes could reflect vascular hypoperfusion in eyes with SO tamponade and may represent a potential cause of retinal thinning and unexplained visual loss.

Visual Acuity-Related Outer Retinal Structural Parameters on Swept Source Optical Coherence Tomography and Angiography in XLRS Patients and Carriers.

To assess the quantitative differences in vessel density and retinal thickness of X-linked retinoschisis (XLRS) patients and RS1 mutation carriers, and the correlation with best-corrected visual acuity (BCVA) with swept source optical coherence tomography (SS-OCT) and OCT angiography (OCTA). We analyzed the correlation between the BCVA of XLRS patients and the SS-OCT and OCTA findings including the detailed structural characteristics of XLRS patients. Besides the schitic changes in various retinal layers, the structural disturbance of outer retina was universally found. In 29 eyes included in the quantitative analysis, XLRS patients showed lower vessel density of the superficial capillary plexus, deep capillary plexus and lower thickness of the outer nuclear layer. BCVA was correlated with the thickness of the outer plexiform layer and outer nuclear layer and the thickness from the outer limiting membrane to the retinal pigment epithelium. Carriers showed higher thickness of outer plexiform layer and smaller foveal avascular zone area. SS-OCT and OCTA could identify the pathological alterations of the individual retinal layers and capillaries, which could pinpoint the exact location of the damages related to visual impairment. In the carriers, the subtle alterations that can be detected with SS-OCT, despite their normal visual acuity, may be caused by the lyonization. Swept source optical coherence tomography can be used as an efficient technique to expose the retinal damage related to visual impairment for prognosis and follow-up.

Retinal hypoperfusion detected by wide-field optical coherence tomographic angiography in a case of retinal racemose hemangioma.

Retinal racemose hemangioma (RRH) is a rare, non-hereditary arteriovenous malformation characterized by the appearance of dilated and tortuous retinal vessels. RRH can develop complications associated with retinal ischemia, such as vitreous hemorrhage, retinal vein occlusion and neovascular glaucoma. Here, we report a case of RRH with retinal hypoperfusion detected by wide-field swept source optical coherence tomography angiography (OCTA), which was not unambiguously illustrated by fluorescein angiography (FA). Case report. A 57-year-old woman was referred to our hospital for the evaluation of severe retinal vascular tortuosity, dilation and retinal hemorrhages in the left eye. Fundus examination revealed arteriovenous communications temporal to the fovea and multiple microaneurysms surrounded by retinal hemorrhages at the midperipheral temporal fundus. In FA, multiple hyperfluorescent lesions with leakage corresponding to microaneurysms were observed in the temporal and lower midperipheral areas; however, non-perfused areas were apparently absent. By contrast, wide-field OCTA clearly showed low-density retinal capillaries in the superotemporal quadrant in comparison with those in the inferotemporal quadrant. Wide-field OCTA detected sparse retinal capillaries, which were not well illustrated by FA, in a patient with RRH. This indicates the presence of low-grade retinal hypoperfusion caused by altered retinal hemodynamics, potentially leading to ischemia-related retinal disorders during a prolonged course, in patients with clinically quiescent RRH.

Three-Year Follow-Up Detecting Choroidal Neovascularization with Swept Source Optical Coherence Tomography Angiography (SS-OCTA) after Successful Half-Fluence Photodynamic Therapy for Chronic Central Serous Chorioretinopathy.

Purpose: To assess the clinical course, structural changes, and choroidal neovascularization detection by SS-OCTA in long-standing and resolved patients with chronic central serous chorioretinopathy (cCSC) after successful half-fluence photodynamic therapy (hf-PDT) treatment. Methods: Twenty-four eyes presenting with cCSC were examined with SS-OCTA and were classified as choroidal neovascular (CNV) or non-choroidal neovascular (non-CNV) cCSC depending on the vascular pattern detected by SS-OCTA after one, two, and three years after hf-PDT. Two groups were compared based on the following clinical findings: demographic characteristics, time of clinical signs, best corrected visual acuity (BCVA), central retinal thickness (CRT), central choroidal thickness (CFT), subretinal fluid (SRF), flat, irregular pigment epithelial detachment (FIPED), and features of fluorescein angiography (FA) and vascular pattern by SS-OCTA. Results: All patients showed resolved cCSC during follow-up after hf-PDT. A total of 5 of 24 (20.8%) eyes showed a neovascular pattern by SS-OCTA. No differences between BCVA, CRT, SRF, FIPED, or FA features were found between both groups (p > 0.05). However, CFT and older age were associated with a neovascular pattern by SS-OCTA (p < 0.05) in follow-up. No signs of neovascular activity were detected by SS-OCT during follow-up in CNV cCSC patients, and no antiVEGF treatment was required for three-year follow-ups. Conclusions: Despite patients with cCSC showing a favorable clinical response after hf-PDT, lower foveal thickness and older age were associated with CNV patterns by SS-OCTA during follow-up.

Swept Source Optical Coherence Tomography Angiography Findings in Birdshot Chorioretinitis: A Cross Sectional Study of 21 Patients

ABSTRACT Purpose Birdshot chorioretinitis (BSCR) is a form of posterior uveitis that is classically characterized by hypopigmented choroidal lesions outside of the major arcades. However, little is known about the extent of choroidal involvement in the macula. We aim to describe the vascular abnormalities observed at the level of the choriocapillaris (CC) in the maculae of BSCR patients, using swept source optical coherence tomography angiography (SS-OCTA). Methods A cross-sectional, observational study was conducted. Eligible patients underwent clinical examination and SS-OCTA imaging. The main outcome measures were the frequency of vascular abnormalities observed at the level of the CC on SS-OCTA and foveal choriocapillaris vascular density (CVD). Results Twenty-one patients were included, with a median age of 61.5 years. All patients had bilateral disease with a median disease duration of 6 years. All but one patient received systemic immunosuppressive drug therapy, and 19 patients had suppressed inflammation on treatment at the time of the SS-OCTA assessment. Of the 42 affected eyes, 39 (92.9%) had gradable SS-OCTA images, with a mean LogMAR visual acuity of 0.18 (Snellen equivalent 20/30). In total, 34 of 39 (87.2%) eyes had some degree of pathologic flow loss, and after controlling for patient age and disease activity, both worse VA and longer disease duration remained statistically significantly associated with reduced foveal CVD. Conclusions Our findings suggest that pathologic CC flow loss in the macula is frequently encountered and may contribute to visual function decline in patients with BSCR. Further studies with longitudinal follow-up are needed to characterize the evolution of these areas of pathologic CC flow loss over time.

CHORIOCAPILLARIS STRUCTURE IN THE FELLOW EYES OF PATIENTS WITH NEOVASCULAR AGE-RELATED MACULAR DEGENERATION

Histological choriocapillaris abnormalities have been reported in age-related macular degeneration (AMD). Averaging multiple en face optical coherence tomography angiography improves the quality of imaging of the choriocapillaris. This study used multiple en face swept source optical coherence tomography angiography image averaging to examine the structural changes in the choriocapillaris in the fellow eyes of patients with neovascular AMD. All patients underwent macular optical coherence tomography angiography imaging. One eye per subject was repeatedly imaged, and nine raster scan sets were obtained. Registered en face images were averaged, and area of flow voids and number of flow voids were measured using ImageJ software. Forty-eight patients with neovascular AMD were recruited for analysis. Twenty-seven patients had polypoidal choroidal vasculopathy, and 22 eyes had soft drusen. Twenty-six eyes of 26 healthy individuals were included as age-matched normal controls. The choriocapillaris had a meshwork appearance in all eyes. The mean flow void area of the choriocapillaris was larger in patients with AMD than normal controls (1.14 ± 0.16 mm2 vs. 1.01 ± 0.12 mm2, P = 0.002). The mean size of each flow void was greater in patients with AMD than normal controls (729 ± 210 µm2 vs. 583 ± 120 µm2, P = 0.003). The mean flow void area of the choriocapillaris was larger in eyes with soft drusen than without soft drusen (1.2 ± 0.2 mm2 vs. 1.1 ± 0.1 mm2, P = 0.024). Multiple en face image averaging revealed precise choriocapillaris structures in the fellow eyes of patients with neovascular AMD.

WF SS-OCTA for detecting diabetic retinopathy and evaluating the effect of photocoagulation on posterior vitreous detachment.

This study aimed to assess the clinical usefulness of widefield swept source optical coherence tomography angiography (WF SS-OCTA) for detecting microvasculature lesions in diabetic retinopathy (DR) by comparing it with ultra-widefield fluorescein angiography (UWFFA) and to investigate the effect of panretinal photocoagulation (PRP) on posterior vitreous detachment (PVD) status. Patients with severe non-proliferative DR (NPDR) or proliferative DR (PDR) who were initially treated with PRP were enrolled. They underwent WF SS-OCTA with a 12×12-mm scan pattern of five visual fixations at baseline and at least a 3-month follow-up after PRP treatment. Patients with no contraindications underwent imaging with UWFFA within a week. Images were evaluated using two methods for the areas of the visible field of view (FOV), non-perfusion area (NPA), presence of neovascularization of the disc (NVD), neovascularization elsewhere (NVE), and PVD status. In total, 44 eyes of 28 patients with DR that were initially treated with PRP were analyzed. The FOV of the UWFFA was significantly wider than that of the WF SS-OCTA. The quantitative measurement of the NPAs was consistent between the two methods. NPAs more than 5DA outside the panoramic OCTA imaging area were detected in 1 eye with NPDR (8.3%) and in 10 eyes with PDR (47.8%). WF SS-OCTA had high detection rates for NVDs and NVEs, with a low rate of false positives. After PRP treatment, no eyes indicated progression in the PVD stages around the macula, optical disc, or NVEs at the short follow-up. WF SS-OCTA is clinically useful for evaluating NPAs and neovascularization in DR. PRP treatment does not induce PVD development in the short term.

Swept source optical coherence tomography and optical coherence tomography angiography for diagnosis and follow‐up of type 2 macular telangiectasia

AbstractPurpose: To report the contribution of swept source optical coherence tomography (SS‐OCT) and OCT‐angiography (OCTA) imaging findings in the diagnosis and the follow‐up of type 2 macular telangiectasia (MacTel 2).Methods: A retrospective study of eight eyes (five patients) with various stages of MacTel2. Clinical staging of MacTel 2 was performed based on SS‐OCT and OCTA.Results: The average age was 63 years old. The mean follow up was 33.6 months. A very early non‐proliferative stage was found in three eyes, an early non‐proliferative stage in three eyes and a late proliferative stage in two eyes. The most common findings on SS‐OCT were disruption of the inner segment‐outer segment (IS/OS) layer in all eyes, parafoveal hyporeflective retinal cavities in four eyes and superficial retinal crystals in three eyes. Two eyes showed irregularity of foveal contour and internal limiting membrane draping associated with retinal vascular channels connecting the superficial and deep retinal layers and forming retinal‐choroidal anastomosis. OCTA findings included capillary telangiectatic changes and enlargement of intercapillary spaces predominantly in deep capillary plexus (DCP) in comparison with superficial capillary plexus (SCP) in all eyes. Irregularity of capillary size in the perifoveal region of the DCP and SCP, predominantly temporal to the fovea, was found in five eyes. Circumferential capillary distortions and subretinal neovascularization at the level of the outer retina and choriocapillaris were detectable in two eyes. At the mean period of follow‐up, lesions were stable in two eyes, an extension of IS/OS disruption was noted in four eyes, parafoveal cavities' appearance and/or extension was found in two eyes and neovascular proliferation appeared in one eye.Conclusions: SS‐OCT and OCTA imaging features facilitate the diagnosis, staging and long‐term follow‐ up of MacTel 2. Further prospective studies are need to characterize the progressive and sequential nature of structural changes in this disease.

Optical coherence tomography angiography findings in patients with essential hypertension

AbstractPurpose: To study the variation of retinal and choroidal density in patients with essential hypertension using Swept Source Optical Coherence Tomography Angiography (SS‐OCT A).Methods: Prospective cross‐sectional study carried out at the Ophthalmology department of Habib Thameur University Hospital of Tunis between June, 1st 2021 and March, 30th 2022. Fifteen volunteer healthy patients (30 eyes) were included. All patients underwent complete ophthalmic examination, measurements of resting systolic and diastolic blood pressure and 3 × 3 and 4.5 × 4.5 SS‐OCT A angiograms in both eyes. Perimeter of avascular central zone (ACZ), superficial retinal plexus density (SRPD), deep retinal plexus density (DRPC) and choriocapillaris capillary vessel density (CVD) were calculated on exported jpg format images using the Fiji Software. Comparative Mann Whitney and Spearman tests were performed using 21.0 SPSS.Results: Eleven males and four females were eligible for the study. Mean age was 53.33 ± 9.73 years. Eight patients (53.3%) with chronic essential hypertension were compared to seven healthy volunteers (46.7%). Mean ACZ, SRPD, DRPD and CVD were respectively 2.62 ± 0.52 mm, 13.20 ± 2.10%, 17.14 ± 1.17% and 51.05 ± 0.85%. Mean systolic blood pressure was 13 ± 5 mmHg and mean diastolic blood pressure was 7.67 ± 5.16 mmHg. CVD was lower in patients with chronic hypertension than in the control group (50.59 vs 51.41, p = 0.047). There were no significant differences between hypertension group and normal group in ACZ, SRPD and DRPC measurements (p = 0.089, p = 0.90 and p = 0.70, respectively). No correlations were found between resting blood pressure values and ACZ measurements.Conclusions: Chronic hypertension does not affect retinal vessels and capillaries quantitative parameters. However, it may alter choroidal vascular structures by decreasing choriocapillaris vessel density. Larger studies are needed to strengthen these results.

Comparative study of lipid profile influence on foveal avascular central zone

AbstractPurpose: To evaluate the influence of lipid profile on foveal avascular central zone (ACZ) using Swept Source Optical Coherence Tomography Angiography (SS‐OCT A).Methods: A cross‐sectional, comparative study including 30 eyes of 15 volunteers with no history of ocular disease or surgery was conducted in the department of ophthalmology of Habib Thameur University Hospital, Tunis. SS‐OCT A imaging was performed using the DRI‐OCT Triton (Topcon, Japan). The macula was imaged using 3 × 3 mm scans, and superficial retinal OCT angiograms were extracted and analysed. Foveal ACZ was characterized by its perimeter, its area, its circularity, the aspect ratio (AR), the roundness index (Round), the solidity and the Feret's diameter (Feret). Patients with dyslipemia were compared to a control group using the Mann–Whitney U‐test and the degree of correlation between two variables was expressed as the Spearman's correlation coefficient.Results: Eleven males and four females were included in the study. Sixteen eyes of eight patients (53.3%) with dyslipemia were compared to fourteen eyes of 7 healthy controls (46.7%). Mean age was 53.33 ± 9.73 years. Mean total ACZ measurements were: Perimeter (2.63 ± 0.53), Area (3.98 ± 1.49), Circularity (7.07 ± 0.97), AR (1.23 ± 0.23), Round (8.32 ± 1.18), Solidity (8.86 ± 0.41) and Feret (6.53 ± 3.24). Comparative study revealed that ACZ area was higher in the dyslipemia group than in the control group (4.64 vs. 3.31, p = 0.02). There was no significant difference between the two groups in the other measurements of ACZ.Conclusions: Dyslipemia causes enlargement of the foveal avascular central zone without affecting its form. These results suggest that dyslipemia may affect foveal vascular structure potentially through chronic ischemia mechanisms.

Evaluation of the effect of cigarette smoking on retina and choroid: An optical coherence tomography angiography study

AbstractPurpose: To study the effect of active cigarette smoking on retinal and choroidal micro‐vascularization using Swept Source Optical Coherence Tomography Angiography (SS‐OCT A).Methods: This is a cross‐sectional, observational, comparative study carried out at the Ophthalmology department of Habib Thameur University Hospital of Tunis. Twelve eyes of “healthy” smokers, 10 eyes of former smokers (less than 3 years after quitting smoking) and 6 eyes of healthy non‐smokers controls were included. SS‐OCT A 3 × 3 mm angiograms were exported and analysed with image J, Fiji Software. Perimeter of avascular central zone (ACZ), superficial retinal plexus density (SRPD), deep retinal plexus density (DRPC) and choriocapillaris capillary vessel density (CVD) were calculated and analysed. Comparative Kruskal Wallis and Spearman tests were performed using 21.0 SPSS.Results: Volunteers with a smoking history had an average of 13.75 ± 10.26 pack‐years. The mean smoking period was 3.2 ± 5.13 years and mean smoking cessation period was 1.28 ± 0.85 years. Mean ACZ, SRPD, DRPD and CVD were respectively 2.62 ± 0.52 mm, 13.20 ± 2.10%, 17.14 ± 1.17% and 51.05 ± 0.85%. There was no significant difference between the three groups for the measurements of ACZ, SRPD, DRPD and CVD (p = 0.57, p = 0.97, p = 0.53 and p = 0.07; respectively). However, there was a significant positive correlation between the smoking cessation period and the DRPD (p = 0.003, r = 0.865).Conclusions: Despite the known effects of nicotine and other chemical substances in cigarettes on peripheral vascular structures, no significant difference in quantitative analysis of retinal and choroidal networks could be found. Deep retinal plexus density seems to increase after long smoking cessation periods.

Central serous chorioretinopathy complicated by neovascularization following panretinal photocoagulation for diabetic retinopathy

AbstractPurpose: To report a case of chronic central serous chorioretinopathy (CSCR) complicated by neovascularization following panretinal photocoagulation (PRP) for a proliferative diabetic retinopathy (DR).Methods: A 51‐year‐old man, with a medical history of diabetes mellitus and chronic CSCR presented to our department for alteration of central vision of the left eye (LE) 6 months after bilateral PRP for proliferative DR. Complete ophthalmic examination with best corrected visual acuity (BCVA) measurement, fundus photography, fundus autofluorescence (FAF), swept source optical coherence tomography (SS‐OCT), swept source optical coherence tomography angiography (SS‐OCTA) and indocyanine green angiography (ICG‐A) were performed.Results: BCVA was 20/100 in the right eye (RE) and 20/400 in the LE. Anterior segment examination was unremarkable except for a cataract in the RE. Fundoscopic examination of the LE showed multiple areas of retinal pigment epithelium (RPE) alteration and a temporal pigment epithelium detachment (PED). FAF showed multiple hypoautofluorescent lesions associated with gravitational tracks. SS‐OCT revealed a serous retinal detachment, a flat irregular PED with a double layer sign overlying a thickened choroid and dilated choroidal vessels. Mid‐phase ICGA revealed 2 discrete areas of hyperfluorescence. SS‐OCTA confirmed the presence of 2 well‐defined choroidal neovascular membranes. The patient was diagnosed with Pachychoroid Neovasculopathy (PNV). After 2 intravitreal bevacizumab injections, SS‐OCT showed complete resolution of the subretinal fluid whereas SS‐OCTA visualized a mature “dead‐tree” shaped membrane.Conclusions: This is an unusual case of chronic CSCR progressing to PNV following PRP for RD. The disruption of an active RPE pump mechanism or release of endogenous stress hormones after PRP have been suggested by some authors as possible causes of this progression. Further studies are needed to elucidate the exact pathogenesis.

Iris Racemose Hemangioma Assessment with Swept Source Optical Coherence Tomography Angiography: A Feasibility Study and Stand-Alone Comparison.

To evaluate arteriovenous malformations (AVM) with swept-source (SS) optical coherence tomography (OCT) angiography (OCTA) in iris racemose hemangioma and compare it with traditional intravenous iris fluorescein angiography (IVFA). A cross-sectional observational clinical study was conducted on patients with iris racemose hemangioma with the ZEISS PLEX Elite 9000 SS OCT & OCTA. Three eyes of three patients were imaged. Iris racemose hemangiomas demonstrated a tortuous, well-defined, and continuous course of the AVM. The ZEISS PLEX Elite 9000 SS OCT & OCTA allowed for a detailed visualization of the ARM and was superior to IVFA in depicting small caliber, fine vessels. SS-OCTA may provide a dye-free, no-injection, cost-effective method comparable to spectral domain OCTA and IVFA for diagnosing and monitoring iris racemose hemangiomas for growth and vascularity.

Age-related assessment of foveal avascular zone and surrounding capillary networks with swept source optical coherence tomography angiography in healthy eyes.

To assess the macular capillary networks and foveal avascular zone (FAZ) with swept-source optical coherence tomography angiography in healthy eyes. This cross-sectional, prospective, observational study enrolled 222 eyes of 116 healthy participants with no ocular or systemic disease. SS-OCTA images were captured using the PLEX Elite 9000 (Carl Zeiss Meditec Inc., Dublin, CA, USA) with a 6 × 6 mm pattern centered on the foveal center. Vessel length density (VLD), perfusion density (PD), and FAZ parameters were analyzed using the manufacturer's automated software. A significant negative correlation was observed between age and average VLD in the superficial plexus, and average PD in both the superficial plexus and the whole retina. A significant positive correlation between age and foveal avascular zone perimeter and area was also noted. Age-wise comparisons showed a trend for an increase in VLD and PD until 40 years of age, with a subsequent decrease in the older age in the macular region. The central subfield showed a decrease in the vessel density measurements in the 21-40 age group. FAZ area and perimeter were the mirror inverse of the central subfield vessel density measurements with a numerically greater area and perimeter in the 21-40 age group compared to the 0-20 and 41-60 age groups. FAZ circularity was significantly reduced after 40 years of age. Age-related changes in the vessel density and FAZ parameters in the healthy macula are complex and vary with the macular location. These results carry significance when interpreting the data from diseased eyes.

Analysis of Microvascular Abnormalities in Obesity: A Comparative Study with Healthy Subjects Using Swept Source Optical Coherence Tomography Angiography and Adaptive Optics

Purpose: The aim of this study was to analyze retinal microvasculature in obese subjects as compared to a normal-weight population. Methods: In this case-control observational study, swept-source optical coherence tomography angiography (SS-OCTA) and adaptive optics (AO) were performed in eyes of nondiabetic, nonhypertensive, obese patients and in healthy controls. AO was used to calculate the wall-to-lumen ratio (WLR). The foveal avascular zone (FAZ), the macular vessel density, and the macular perfusion density of the superficial and deep capillary plexuses were analyzed in 6 × 6 mm macular OCTA cubes. SS-OCTA was also used to measure the choroidal thickness, the retinal nerve fiber layer (RNFL), and the vascular density of the retinal peripapillary capillary plexus. Results: The obese group included 45 eyes (24 patients), and the control group included 46 eyes (23 subjects). The central macular density and perfusion density were significantly lower in obese patients compared to controls, in the deep retinal layer (0.28 [0.01–0.69] vs. 1.24 [0.82–1.66], p = 0.006 and 0.006 [0.001–0.015] vs. 0.025 [0.016–0.034], p = 0.01), respectively, after adjustment for systolic blood pressure. No differences were found in macular vascular density in other areas, FAZ (circularity, area, perimeter), choroidal thickness, RNFL. WLR was increased in obese patients (0.252 [0.246–0.259] vs. 0.239 [0.231–0.245] in controls, p = 0.016). Conclusion: Obesity was associated with retinal microvascular changes regardless of the presence of diabetes and hypertension. Our findings suggest the presence of infraclinical microvascular changes directly associated with obesity, which can be identified noninvasively through retinal imaging.

PREDICTORS OF RETINAL PIGMENT EPITHELIUM TEAR DEVELOPMENT AFTER TREATMENT FOR NEOVASCULAR AGE-RELATED MACULAR DEGENERATION USING SWEPT SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

The purpose of this study was to investigate the predictors of retinal pigment epithelium (RPE) tear development after treatment for neovascular age-related macular degeneration using swept source optical coherence tomography angiography. This prospective study included 152 treatment-naïve eyes with neovascular age-related macular degeneration without high myopia that were followed up for 1 year after treatment. Eligible eyes were classified into eyes with or without RPE tear development. They were matched in a 1:2 ratio. The areas of choroidal neovascularization (CNV) and RPE detachment (pigment epithelial detachment [PED]) were measured from optical coherence tomography angiography and OCT en face images, respectively. The optical coherence tomography angiography-specific parameters representing CNV status were analyzed. Eight (5.3%) of the 152 eyes developed RPE tears (RPE tear group). After matching, 16 eyes without RPE tears were analyzed (non-RPE tear group). The ratio of the CNV/PED area was lower in the RPE tear group than that in the non-RPE tear group (P = 0.007). The PED area was broader (P = 0.008), and PED height was greater in the RPE tear group (P = 0.04). Optical coherence tomography angiography-specific parameters did not differ between the two groups. Neovascular age-related macular degeneration with pretreatment broad PED, high PED, and small CNV area relative to the PED area has a high risk of RPE tear development after therapy. However, CNV status may not have an association.

Investigation of Macular Structural and Microcirculatory Characteristics of Posterior Staphyloma in High Myopic Eyes by Swept Source Optical Coherence Tomography Angiography.

Purpose: To investigate the characteristics of macular structures and microcirculation of posterior staphyloma (PS) and explored factors related to PS in eyes with high myopia. Methods: There were 114 eyes of 82 patients in this study. Using 1:1 matching of the axial length of myopic eyes, patients were divided into no PS (NPS) and PS groups. Comprehensive ophthalmic examinations were performed on all patients. Structural parameters were acquired using swept source optical coherence tomography (SS-OCT). OCT angiography (OCTA) was used to measure the microcirculation parameters. Generalized estimated equation and linear correlation analysis were used for the statistical analysis. Results: Patients with PS had a thinner retinal thickness (RT) and choroid thickness (CT) (all p < 0.05) in the measurement areas and a significantly lower subfoveal scleral thickness (SFST) (p < 0.001) than those without PS. Retinal deep vascular complex density (DVD) (all p < 0.05) and choriocapillaris perfusion area (CCPA) (all p < 0.001) were significantly lower in the measurement areas of the PS group than in those of the NPS group. There was no significant difference in the retinal superficial vascular density between the two groups. Generalized estimating equation indicated that SFST (B = 0.079, p = 0.001), parafoveal RT (B = −0.162, p = 0.041), foveal CT (B = 0.292, p = 0.013), parafoveal CT (B = −0.157, p = 0.023), foveal CCPA (B = 0.691, p = 0.003) and parafoveal CCPA (B = −0.026, p = 0.004) were significantly correlated with PS. Age (r = −0.323, p = 0.001), spherical equivalent refraction (SER) (r = 0.289, p = 0.004), subfoveal CT (r = 0.398, p < 0.001), foveal DVD (r = 0.346, p < 0.001), foveal CT (r = 0.429, p < 0.001), and foveal CCPA (r = 0.387, p < 0.001) were strongly correlated with SFST. Conclusions: The macular structures and microcirculation in the PS group were different from those in the NPS group. SFST, CT, and CCPA were significantly correlated with PS. Lower SFST in PS was correlated with abnormalities of CT and microcirculation.

MACULAR SENSITIVITY AND CAPILLARY PERFUSION IN HIGHLY MYOPIC EYES WITH MYOPIC MACULAR DEGENERATION.

To evaluate the interrelationship between macular sensitivity and retinal perfusion density (PD) in eyes with myopic macular degeneration (MMD). One hundred and thirty-eight highly myopic eyes from 82 adult participants were recruited. Macular sensitivity was evaluated using the Microperimeter MP-3. Retinal PD was measured using the PLEX Elite 9000 swept source optical coherence tomography angiography. Macular sensitivity values between different categories of MMD and its relationship with optical coherence tomography angiography measurements were evaluated using multivariable linear mixed models, adjusting for age and axial length. Macular sensitivity reduced with increasing severity of MMD (β ≤ -0.95, P < 0.001), whereas the best-corrected visual acuity was not associated with MMD severity (P > 0.04). Persons who were older (β = -0.08, P < 0.001), with longer axial length (β = -0.32, P = 0.005), presence of macular diffuse choroidal atrophy (β = -2.16, P < 0.001) or worse MMD (β = -5.70, P < 0.001), and presence of macular posterior staphyloma (β ≤ -2.98, P < 0.001) or Fuchs spot (β = -1.58, P = 0.04) were associated with reduced macular sensitivity. Macular sensitivity was significantly associated with deep retinal PD in MMD (β = 0.15, P = 0.004) but not with superficial retinal PD (P = 0.62). There was a strong correlation between reduced macular sensitivity and increasing MMD severity, even in mild MMD independent of the best-corrected visual acuity. Furthermore, macular sensitivity was correlated with deep retinal PD, suggesting a vasculature-function relationship in MMD.