scholarly journals Clinical Utility of Artificial Intelligence Algorithms to Enhance Wide-Field Optical Coherence Tomography Angiography Images

2021 ◽  
Vol 7 (2) ◽  
pp. 32
Author(s):  
Orlaith Mc Grath ◽  
Mohammad W. Sarfraz ◽  
Abha Gupta ◽  
Yan Yang ◽  
Tariq Aslam

The aim of this paper is to investigate the clinical utility of the application of deep learning denoise algorithms on standard wide-field Optical Coherence Tomography Angiography (OCT-A) images. This was a retrospective case-series assessing forty-nine 10 × 10 mm OCT-A1 macula scans of 49 consecutive patients attending a medical retina clinic over a 6-month period. Thirty-seven patients had pathology; 13 had none. Retinal vascular layers were categorised into superficial or deep capillary plexus. For each category, the retinal experts compared the original standard image with the same image that had intelligent denoise applied. When analysing the Superficial Capillary Plexus (SCP), the denoised image was selected as “best for clinical assessment” in 98% of comparisons. No difference was established in the remaining 2%. On evaluating the Deep Capillary Plexus (DCP), the denoised image was preferred in 35% of comparisons. No difference was found in 65%. There was no evidence of new artefactual features nor loss of anatomical detail in denoised compared to the standard images. The wide-field denoise feature of the Canon Xephilio OCT-A1 produced scans that were clinically preferable over their original OCT-A images, especially for SCP assessment, without evidence for causing a new artefactual error.

2021 ◽  
Author(s):  
Ali Torkashvand ◽  
Hamid Riazi-Esfahani ◽  
Fariba Ghassemi ◽  
Elias Khalil Pour ◽  
Babak Masoomian ◽  
...  

Abstract BACKGROUND: To assess the impact of brachytherapy on macular microvasculature utilizing optical coherence tomography angiography (OCTA) in treated choroidal melanoma.METHODS: In this retrospective observational case series, we reviewed the recorded data of the patients with choroidal melanoma treated with rheuthenium-106 (106Ru) plaque radiotherapy with follow-up period of more than 6 months. Automatically measured OCTA retinal parameters were analyzed after image processing. The non-irradiated fellow eye is considered as the control.RESULTS: Thirty-one eyes of 31 patients with the mean age of 51.1 years were recruited. Six eyes had no radiation maculopathy (RM). From 25 eyes with RM, nine eyes (36%) revealed a burnout macular microvasculature with imperceptible vascular details. Foveal and optic disc radiation dose had the highest value to predict the burnout pattern (ROC, AUC: 0.763, 0.727). Superficial and deep foveal avascular zone (FAZ) were larger in irradiated eyes in comparison to healthy eyes (1629 µm2 vs. 428 µm2, P =0.005; 1837 µm2 vs 268 µm2, P =0.021; respectively). Foveal and parafoveal vascular area density (VAD) and vascular skeleton density (VSD) in both superficial and deep capillary plexus (SCP and DCP) were decreased in all irradiated eyes in comparison with control eyes (P< 0.001). Compared with fellow healthy eyes, irradiated eyes without RM had significantly lower VAD and VSD at foveal and parafoveal DCP (all P<0.02). However, these differences at SCP were not statistically significant. CONCLUSION: The OCTA is a valuable tool for evaluating RM. Initial subclinical microvascular insult after 106Ru brachytherapy is more likely to occur in DCP. The deep FAZ area was identified as a more critical biomarker of BCVA than superficial FAZ in these patients.


2021 ◽  
pp. bjophthalmol-2021-319540
Author(s):  
Jade Y. Moon ◽  
Itika Garg ◽  
Ying Cui ◽  
Raviv Katz ◽  
Ying Zhu ◽  
...  

Background/aimsPathological myopia (PM) is a leading cause of blindness worldwide. We aimed to evaluate microvascular and chorioretinal changes in different stages of myopia with wide-field (WF) swept-source (SS) optical coherence tomography angiography (OCTA).MethodsThis prospective cross-sectional observational study included 186 eyes of 122 patients who had undergone imaging between November 2018 and October 2020. Vessel density (VD) and vessel skeletonised density (VSD) of superficial capillary plexus, deep capillary plexus and whole retina, as well as foveal avascular zone parameters, retinal thickness (RT) and choroidal thickness (CT), were calculated.ResultsThis study evaluated 75 eyes of 48 patients with high myopia (HM), 43 eyes of 31 patients with mild to moderate myopia and 68 eyes of 53 age-matched controls. Controlling for age and the presence of systemic hypertension, we found that HM was associated with decrease in VD and VSD in all layers on 12×12 mm² scans. Furthermore, HM was associated with a VD and VSD decrease in every Early Treatment Diabetic Retinopathy Study grid, with a larger decrease temporally (βVD=−0.39, βVSD=−10.25, p<0.01). HM was associated with decreased RT and CT. Reduction in RT was outside the macular region, while reduction in CT was in the macular region.ConclusionUsing WF SS-OCTA, we identified reduction in microvasculature and structural changes associated with myopia. Decrease in VD and VSD was greater in the temporal quadrant, and reductions in RT and CT were uneven across the retina. Further work may help identify risk factors for the progression of PM and associated vision-threatening complications.


2019 ◽  
Vol 4 (1) ◽  
pp. e000244 ◽  
Author(s):  
Livia Faes ◽  
Zaria Ali ◽  
Siegfried Wagner ◽  
Praveen J Patel ◽  
Dun Jack Fu ◽  
...  

ObjectiveTo compare clinical characteristics of patients suffering from neovascular age-related macular degeneration (nAMD) with mature and immature choroidal neovascularisation (CNV) as assessed by optical coherence tomography angiography (OCTA). To explore the effect of total anti-vascular endothelial growth factor exposure on the occurrence of mature CNV when correcting for potential confounders.Methods and analysisIn this retrospective case series, we included 40 eyes of 36 patients with nAMD with CNV assessed by OCTA at the Manchester Eye Hospital between June 2016 and June 2017. A retinal specialist masked to patient information graded CNV depicted on OCTA scans. For statistical comparisons, we used t-tests, Fisher’s exact tests and a mixed-effects logistic regression model.Results18 patients (20 eyes) were treatment naïve, and the mean number of intravitreal injections (IVI) in the remaining eyes was 18.4 (range 2–71). The mean duration of nAMD was 19.3 months (range 0–87.4). 25 eyes (62.5%) exhibited mature CNV. Eyes with mature CNV did not differ from those with immature CNV regarding age (+2.8 years; p=0.288) or duration of disease (+9.4 months; p=0.061). However, they had a higher number of IVIs (+3.1; p=0.035). Among eyes with best corrected visual acuity over 25 letters, there was a strong association between the number of IVIs (0 vs 1–20: OR 68.01 [95% CI 1.30 to 3546.99; p=0.036], 0 vs >20 IVI: OR 380.01 [95% CI 2.60 to 55 464.89; p=0.019]) and maturity status when correcting for potential confounders.ConclusionMaturity status of CNV as assessed by OCTA may indicate treatment exposure of CNV in nAMD.


2019 ◽  
Author(s):  
Houshang Faghihi ◽  
Hamid Riazi-Esfahani ◽  
Alireza Khodabandeh ◽  
Ahmad Mirshahi ◽  
Fariba Ghasemi ◽  
...  

Abstract Background: To evaluate the changes of macular vascular density in the superficial capillary (SCP) and the deep capillary plexus (DCP), Foveal avascular area (FAZ), choroidal flow, macular thickness and parapapillary flow after panretinal photocoagulation (PRP).Method: In this prospective interventional non-comparative case series, patients with very severe nonproliferative (NPDR) and early proliferative diabetic retinopathy (PDR) and no significant macular edema who were candidates for panretinal photocoagulation underwent measurement of corrected distance visual acuity (CDVA), optical coherence tomography (OCT), Optical coherence tomography angiography (OCTA) at the baseline (1–5 days before PRP), 1, and 5 to 7 months following completion of PRP treatment.Results: Thirty-nine eyes from 21 patients with diabetes were enrolled. foveal SCP (P > 0.1), foveal DCP (P > 0.1), parafoveal SCP (P > 0.1), and parafoveal DCP (P > 0.1) did not change 1 month and 6 months after PRP. The parafoveal inner retina thick slab density was significantly decreased at 6 months after PRP (p=0.015). Deep FAZ area constricted 6 months following PRP (P = 0.075). Based on calculated circularity index, the FAZ area became significantly more circular. (P=0.047). One month after PRP the inside disc vascular density was significantly increased from baseline (p=0.041); while, it was decreased to lower than baseline amount, 6 months after PRP .Conclusion: Although OCTA parameters were not significantly affected by PRP at both short- (1-month) long-term (6-month) follow-up, but FAZ area may be become more circular and regular after PRP may be due to reflow of occluded capillary plexus.


2020 ◽  
pp. 112067212095264
Author(s):  
Hooshang Faghihi ◽  
Hamid Riazi-Esfahani ◽  
Alireza Khodabande ◽  
Elias Khalili Pour ◽  
Ahmad Mirshahi ◽  
...  

Background: To evaluate the changes of macular vascular density in the superficial capillary (SCP) and the deep capillary plexus (DCP), foveal avascular area (FAZ), choroidal flow, and macular thickness after pan-retinal photocoagulation (PRP). Methods: In this prospective interventional non-comparative case series, patients with very severe nonproliferative (NPDR) and early proliferative diabetic retinopathy (PDR) and no significant macular edema who were candidates for pan-retinal photocoagulation underwent measurement of corrected distance visual acuity (CDVA), optical coherence tomography (OCT), Optical coherence tomography angiography (OCTA) at the baseline, 1, and 6 months following completion of PRP treatment. Results: Thirty-nine eyes from 21 patients with diabetes were enrolled. Superficial and deep capillary plexus densities in the foveal and parafoveal area didn’t change significantly 1 and 6 months post-PRP ( p > 0.1 in all of them). The FAZ area constricted 6 months following PRP ( p = 0.075). Based on the calculated circularity index, the FAZ became significantly more circular after 6 months of follow-up ( p = 0.047). Although the choroidal flow area increased after PRP this increase wasn’t statically significant neither at 1 month nor at 6 months post-PRP ( p = 0.31 and 0.23, respectively). Conclusion: Although OCTA parameters were not significantly affected by PRP at both short-term (1 month) and long-term (6 months) follow-ups, the FAZ area became significantly circular after PRP may be due to redistribution of blood flow in hypoperfused foveal capillary plexus.


2018 ◽  
Vol 103 (9) ◽  
pp. 1289-1295 ◽  
Author(s):  
Meng Tian ◽  
Christoph Tappeiner ◽  
Martin S Zinkernagel ◽  
Wolfgang Huf ◽  
Sebastian Wolf ◽  
...  

PurposeTo evaluate vascular changes in patients with intermediate uveitis with or without retinal vasculitis using swept-source wide-field optical coherence tomography angiography (OCTA).MethodsThis is a prospective cross-sectional study. Consecutive patients with intermediate uveitis were evaluated using wide-field OCTA. Wide-field OCTA and en-face OCT images were analysed for the presence of capillary non-perfusion and reduced perfusion, disruption of ellipsoid zone, and abnormalities on en-face wide-field retinal thickness maps, respectively, and compared with fluorescein angiography (FA) findings in a subcohort.Results164 eyes of 88 patients with intermediate uveitis were included. Areas of capillary non-perfusion and reduced perfusion were more frequently observed in the choroidal OCTA slab (33.3% and 49.4%), choriocapillaris (CC; 31.4% and 48%) and deep capillary plexus (DCP; 9.6% and 34.6%) than in the superficial capillary plexus (SCP; 5% and 26.3%), respectively. Intermediate uveitis with vasculitis presented more frequently with non-perfusion and hypoperfusion in the DCP (p=0.003 and p=0.05, respectively) and SCP (p=0.007 and p=0.005, respectively) than intermediate uveitis without vasculitis. Peripheral capillary leakage on FA correlated with the presence of perivascular, macular and generalised thickening on en-face wide-field thickness maps (p=0.007). Ischaemia on FA was significantly associated with non-perfusion on wide-field OCTA in SCP and DCP (p=0.019 and p=0.027, respectively).ConclusionChanges in the choroid, CC and DCP are more frequently found than in the SCP on wide-field OCTA in intermediate uveitis. While wide-field OCTA is a reliable tool to detect capillary non-perfusion in intermediate uveitis, it was not helpful in determining disease activity.Trial registration numberNCT02811536.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ali Torkashvand ◽  
Hamid Riazi-Esfahani ◽  
Fariba Ghassemi ◽  
Elias Khalili Pour ◽  
Babak Masoomian ◽  
...  

Abstract Background To assess the impact of brachytherapy on macular microvasculature utilizing optical coherence tomography angiography (OCTA) in treated choroidal melanoma. Methods In this retrospective observational case series, we reviewed the recorded data of the patients with unilateral extramacular choroidal melanoma treated with ruthenium − 106 (106Ru) plaque radiotherapy with a follow-up period of more than 6 months. Automatically measured OCTA retinal parameters were analysed after image processing. Results Thirty-one eyes of 31 patients with the mean age of 51.1 years were recruited. Six eyes had no radiation maculopathy (RM). From 25 eyes with RM, nine eyes (36%) revealed a burnout macular microvasculature with imperceptible vascular details. Twenty-one non-irradiated fellow eyes from the enrolled patients were considered as the control group. Foveal and optic disc radiation dose had the highest value to predict the burnout pattern (ROC, AUC: 0.763, 0.727). Superficial and deep foveal avascular zone (FAZ) were larger in irradiated eyes in comparison to non-irradiated fellow eyes (1629 μm2 vs. 428 μm2, P = 0.005; 1837 μm2 vs 268 μm2, P = 0.021; respectively). Foveal and parafoveal vascular area density (VAD) and vascular skeleton density (VSD) in both superficial and deep capillary plexus (SCP and DCP) were decreased in all irradiated eyes in comparison with non-irradiated fellow eyes (P < 0.001). Compared with non-irradiated fellow eyes, irradiated eyes without RM had significantly lower VAD and VSD at foveal and parafoveal DCP (all P < 0.02). However, these differences at SCP were not statistically significant. Conclusion The OCTA is a valuable tool for evaluating RM. Initial subclinical microvascular insult after 106Ru brachytherapy is more likely to occur in DCP. The deep FAZ area was identified as a more critical biomarker of BCVA than superficial FAZ in these patients.


Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 808
Author(s):  
Max Philipp Brinkmann ◽  
Nikolas Xavier Kibele ◽  
Michelle Prasuhn ◽  
Vinodh Kakkassery ◽  
Mario Damiano Toro ◽  
...  

Optical coherence tomography angiography (OCTA) is a non-invasive tool for imaging and quantifying the retinal and choroidal perfusion state in vivo. This study aimed to evaluate the acute effects of isometric and dynamic exercise on retinal and choroidal sublayer perfusion using OCTA. A pilot study was conducted on young, healthy participants, each of whom performed a specific isometric exercise on the first day and a dynamic exercise the day after. At baseline and immediately after the exercise, heart rate (HR), mean arterial pressure (MAP), superficial capillary plexus perfusion (SCPP), deep capillary plexus perfusion (DCPP), choriocapillaris perfusion (CCP), Sattlers’s layer perfusion (SLP), and Haller’s layer perfusion (HLP) were recorded. A total of 34 eyes of 34 subjects with a mean age of 32.35 ± 7.87 years were included. HR as well as MAP increased significantly after both types of exercise. Both SCPP and DCPP did not show any significant alteration due to isometric or dynamic exercise. After performing dynamic exercise, CCP, SLP, as well as HLP significantly increased. Changes in MAP correlated significantly with changes in HLP after the dynamic activity. OCTA-based analysis in healthy adults following physical activity demonstrated a constant retinal perfusion, supporting the theory of autoregulatory mechanisms. Dynamic exercise, as opposed to isometric activity, significantly changed choroidal perfusion. OCTA imaging may represent a novel and sensitive tool to expand the diagnostic spectrum in the field of sports medicine.


2021 ◽  
pp. 247412642199733
Author(s):  
Kyle D. Kovacs ◽  
M. Abdallah Mahrous ◽  
Luis Gonzalez ◽  
Benjamin E. Botsford ◽  
Tamara L. Lenis ◽  
...  

Purpose: This work aims to evaluate the clinical utility and feasibility of a novel scanning laser ophthalmoscope-based navigated ultra-widefield swept-source optical coherence tomography (UWF SS-OCT) imaging system. Methods: A retrospective, single-center, consecutive case series evaluated patients between September 2019 and October 2020 with UWF SS-OCT (modified Optos P200TxE, Optos PLC) as part of routine retinal care. The logistics of image acquisition, interpretability of images captured, nature of the peripheral abnormality, and clinical utility in management decisions were recorded. Results: Eighty-two eyes from 72 patients were included. Patients were aged 59.4 ± 17.1 years (range, 8-87 years). During imaging, 4.4 series of images were obtained in 4.1 minutes, with 86.4% of the image series deemed to be diagnostic of the peripheral pathology on blinded image review. The most common pathologic findings were chorioretinal scars (18 eyes). In 31 (38%) eyes, these images were meaningful in supporting clinical decision-making with definitive findings. Diagnoses imaged included retinal detachment combined with retinoschisis, retinal hole with overlying vitreous traction and subretinal fluid, vitreous inflammation overlying a peripheral scar, Coats disease, and peripheral retinal traction in sickle cell retinopathy. Conclusions: Navigated UWF SS-OCT imaging was clinically practical and provided high-quality characterization of peripheral retinal lesions for all eyes. Images directly contributed to management plans, including laser, injection or surgical treatment, for a clinically meaningful set of patients (38%). Future studies are needed to further assess the value of this imaging modality and its role in diagnosing, monitoring, and treating peripheral lesions.


Author(s):  
Marina Concilio ◽  
Federica Fossataro ◽  
Daniela Montorio ◽  
Mariapaola Giordano ◽  
Gilda Cennamo

Abstract Purpose To quantitatively investigate the role of deep capillary plexus (DCP) in patients affected by type 3 macular neovascularization (MNV), compared to patients with reticular pseudodrusen (RPD) eyes and healthy controls, using optical coherence tomography angiography (OCTA). Methods In this prospective observational study, a total of seventy-eight eyes of 78 patients were included. Group 1 consisted of 40 eyes of 40 patients with stage 1 of type 3 MNV (22 males, 18 females, mean age 73.7, SD ± 6.60) and group 2 included 38 eyes of 38 patients with RPD (17 males, 21 females, mean age 73.2, SD ± 4.55). The control group included 40 eyes of 40 healthy subjects (20 males, 20 females, mean age 71.4, SD ± 6.36 years). We evaluated the retinal vessel density (VD) of superficial capillary plexus (SCP) and deep capillary plexus (DCP) using OCTA. Results Patients with diagnosis of type 3 MNV showed statistically lower values of VD in DCP with respect to controls and to RPD group (p < 0.001), while there were no statistical differences between RPD and control group in macular region. No significant differences in VD of SCP were detected among the three study groups. Conclusion OCTA provides a reproducible, non-invasive detailed quantitative analysis of retinal vascular features and changing in early-stage type 3 MNV patients, which allowed to shed the light on the main role of DCP ischemia in the development of type 3 MNV.


Sign in / Sign up

Export Citation Format

Share Document