Hemodynamic and structural changes in retinal arterial macroaneurysm after intravitreal anti-vascular endothelial growth factor injection

High resolution imaging with optical coherence tomography angiography and offset pinhole adaptive optics scanning light ophthalmoscope helped us visualize the hemodynamic and structural changes in a ruptured retinal arterial macroaneurysm in a 78-year-old woman. Intravitreal injection of anti-vascular endothelial growth factor was administered to ameliorate the condition

Retinal arterial macroaneurysm rupture caused by dissection-like change in the vessel wall

[Purpose] To highlight a potential pathogenetic mechanism of retinal arterial macroaneurysm. [Observations] A 79-year-old woman presented with a ruptured retinal arterial macroaneurysm in the right eye. One year after treatment, high-resolution multimodal imaging with optical coherence tomography (OCT), OCT angiography, and adaptive optics scanning light ophthalmoscope showed that a narrow passage developed in the vessel wall of the pre-existing retinal arterial macroaneurysm and another macroaneurysm had developed adjacent to the pre-existing one. [Conclusions and Importance] These images suggest the pathogenesis of retinal arterial macroaneurysm (RAM) associated with crack-like changes in the retinal arterial wall, similar to pathologies seen in systemic arteries

Peripheral Chorioretinal Imaging Through a Front Prism on Optical Coherence Tomography Angiography

Purpose: To evaluate the clinical feasibility of peripheral chorioretinal imaging through a front prism on swept-source optical coherence tomography angiography (SS-OCTA). Methods: We prospectively obtained en face OCTA images using SS-OCTA in 10 eyes of 10 healthy volunteers. For the peripheral chorioretinal imaging, the scanning laser passed and refracted through a 45 −90 −45 right-angle prism. We evaluated the qualitative and quantitative characteristics of chorioretinal vessels in the periphery. Results: Using peripheral chorioretinal imaging through a prism, the retinal vasculature was delineated to the equator on the OCTA images, and varices of the vortex vein ampullae were observed on choroidal OCT images. The 3×3-mm images revealed three-dimensional morphologies unique to the peripheral vasculature, such as the gap between retinal arterioles and venules in the superficial capillary plexus (SCP) and elliptical and greater lobules in the choriocapillaris layer. Compared with OCTA images obtained without the prism, those obtained through the prism demonstrated an approximately 1.24-fold increase in the lengths in the base apex direction, whereas the lengths in the perpendicular direction showed concordance. The peripheral vessel density (VD) in the inferior quadrant was lower than those in the other quadrants on the SCP and deep capillary plexus, whereas on the SCP images of the macula the lowest VD was observed in the temporal subfield. Conclusions: Peripheral chorioretinal imaging allowed us to generate ultra-widefield panoramic OCTA images and demonstrated morphologic characteristics unique to peripheral chorioretinal vessels. Translational Relevance: OCTA imaging through a front prism can be a technique for acquiring chorioretinal vasculature images in the periphery

Human Foveal Cone and Müller Cells Examined by Adaptive Optics Optical Coherence Tomography

Purpose: The purpose of this study was to image and investigate the foveal microstructure of human cone and Müller cells using adaptive optics-optical coherence tomography. Methods: Six healthy subjects underwent the prototype adaptive optics-optical coherence tomography imaging, which allowed an axial resolution of 3.4 µm and a transverse resolution of approximately 3 µm. The morphological features of the individual retinal cells observed in the foveola were qualitatively and quantitatively evaluated. Results: In the six healthy subjects, the image B-scans showed hyper-reflective dots that were densely packed in the outer nuclear layer. The mean number, diameter, and density of hyper-reflective dots in the foveola were 250.8 ± 59.6, 12.7 ± 59.6 µm, and 6966 ± 1833/mm², respectively. These qualitative and quantitative findings regarding the hyper-reflective dots were markedly consistent with the morphological features of the foveal cone cell nuclei. Additionally, the images showed the funnel-shaped hyporeflective bodies running vertically and obliquely between the inner and external limiting membranes, illustrating the cell morphology of the foveal Müller cells. Conclusions: Using adaptive optics, we succeeded in visualizing cross-sectional images of the individual cone and Müller cells of the human retina in vivo. Translational Relevance: Adaptive optics-optical coherence tomography would help to improve our understanding of the pathogenesis of macular diseases

DETECTION AND CHARACTERISTICS OF UNRUPTURED RETINAL ARTERIAL MACROANEURYSMS

Purpose: To determine the presence of unruptured retinal arterial macroaneurysms (RAMs) and to examine the characteristics of the detected lesions. Methods: This retrospective observational study included the affected and contralateral eyes of 50 patients (100 eyes) with symptomatic, unilateral, ruptured RAMs who visited the Department of Ophthalmology at the Kyoto University Hospital (April 2014–April 2020) and were followed up for at least 6 months after the onset. The presence and characteristics of unruptured RAMs were examined by reviewing the findings of color fundus photography and infrared scanning laser ophthalmoscopy performed before the onset or during the follow-up period. Results: Unruptured RAMs were detected in six of the 50 patients. Some patients had bilateral or multiple unruptured RAMs, and a total of 12 unruptured RAMs were detected in eight eyes of the six patients. Among the detected lesions, eight exhibited a longitudinal increase in their diameter during the follow-up period, whereas six exhibited ruptures. Conclusion: Unruptured RAM is not an uncommon retinal vascular abnormality and can enlarge and progress to ruptured RAM

MACULAR BLOOD FLOW CHANGES IN BRANCH RETINAL VEIN OCCLUSION EXAMINED BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY VARIABLE INTERSCAN TIME ANALYSIS

Purpose: To examine the relationship between changes in retinal blood flow and the recurrence of macular edema in eyes with branch retinal vein occlusion. Methods: This observational study included 32 eyes in 32 patients (18 men and 14 women) with branch retinal vein occlusion who visited the Department of Ophthalmology at Kyoto University Hospital (February 2021–November 2021). At the time of inclusion in the study, each patient underwent optical coherence tomography angiography on a macular area measuring 4 × 4 mm2. For variable interscan time analysis, different interscan times were set at 7.6 (IST7.6) and 20.6 ms (IST20.6) for the optical coherence tomography angiography. The parafoveal vessel densities were measured sectorally at IST7.6 and IST20.6, and their relationship with the longitudinal changes evident in the retinal thicknesses during the variable interscan time analysis examination and 2 months later was evaluated. Results: The parafoveal vessel densities in the affected sector was significantly greater at IST20.6 than at IST7.6 (P = 0.011). At 2 months after the variable interscan time analysis examination, 6 patients (19%) showed recurrence of macular edema involving the fovea. The difference in the parafoveal vessel densities (IST20.6 − IST7.6) in the affected sector was significantly associated with longitudinal retinal thickening in the corresponding parafovea (P = 0.020) and fovea (P = 0.014). Conclusion: In eyes with branch retinal vein occlusion, optical coherence tomography angiography variable interscan time analysis facilitated the detection of retinal blood flow changes that might be predictive for the recurrence of macular edema

Prevention of Image Quality Degradation in Wider Field Optical Coherence Tomography Angiography Images Via Image Averaging

Purpose: To evaluate the mutual effect of widening the field of view and multiple en face image averaging on the quality of optical coherence tomography angiography (OCTA) images. Methods: This prospective, observational, cross-sectional case series included 20 eyes of 20 healthy volunteers with no history of ocular or systemic disease. OCTA imaging of a 3 × 3-mm, 6 × 6-mm, and 12 × 12-mm area centered on the fovea was performed nine times using the PLEX Elite 9000. We acquired averaged OCTA images generated from nine en face OCTA images. The corresponding areas in the three scan sizes were evaluated for the original single-scanned OCTA images and averaged OCTA images both qualitatively and quantitatively. Quantitative measurements included vessel density (VD), vessel length density (VLD), fractal dimension (FD), and contrast-to-noise ratio (CNR). Results: Significant differences in VD, VLD, FD, and CNR (P < 0.001) were observed due to the mutual effect of averaging and differences in scan size. Both qualitative and quantitative evaluations indicated that the quality of 6 × 6-mm averaged images was equal to or better than that of 3 × 3-mm single-scanned images. However, the quality of 12 × 12-mm averaged images did not reach that of 3 × 3-mm single-scanned images. Conclusions: To some extent, multiple en face OCTA image averaging can compensate for the deterioration in image quality caused by widening the field of view. Translational Relevance: Multiple en face OCTA image averaging can be a technique for acquiring wider field OCTA images with good quality

Prediction of trabecular meshwork-targeted micro-invasive glaucoma surgery outcomes using anterior segment OCT angiography

前眼部OCTAを用いた線維柱帯切開術効果予測 --房水主流出路の可視化による緑内障手術予後予測の可能性--. 京都大学プレスリリース. 2021-09-09.We performed a prospective, longitudinal study to investigate the association between the preoperative intrascleral vasculature assessed using anterior segment (AS)-optical coherence tomography angiography (OCTA) and surgical outcomes of trabecular meshwork-targeted micro- or minimally invasive glaucoma surgery (MIGS). We included 37 patients with primary open-angle glaucoma. Preoperative AS-OCTA images of the sclero-conjunctiva of the nasal corneal limbus were acquired in the superficial (conjunctival) and deep (intrascleral) layers. The vessel densities (VDs) of each layer were measured separately in the entire area, limbal side, and fornix area. Surgical success was determined by postoperative intraocular pressure (IOP) and IOP reduction. Twenty-three and 14 eyes were classified as having successful and unsuccessful outcomes, respectively. The deep VDs of the entire area and fornix area were significantly lower in the successful group (P = 0.031 and P = 0.009). The success rate was significantly higher for eyes with a lower deep VD than for eyes with a higher deep VD. A greater IOP reduction was significantly associated with lower deep VD in the fornix area (P = 0.022) and higher preoperative IOP (P < 0.001). These results indicate that intrascleral vasculature assessed using preoperative AS-OCTA was negatively correlated with surgical success and IOP reduction resulting from trabecular meshwork-targeted MIGS. AS-OCTA images might help predict MIGS outcomes

Factors associated with extremely poor visual outcomes in patients with central retinal vein occlusion

Here, we examined prognostic factors for extremely poor visual outcomes in patients with central retinal vein occlusion (CRVO) in actual practices. We included 150 consecutive eyes with treatment-naïve acute CRVO from four different facilities and observed them for over 24 months. Macular edema (ME) was treated with one or three monthly anti-vascular endothelial growth factor injections (1 or 3 + pro re nata). According to the final Snellen visual acuity (VA), we divided the patients into very poor VA (< 20/200) and control (≥ 20/200) groups and examined risk factors for poor final visual outcomes. The baseline Snellen VA was hand motion to 20/13. The mean number of anti-VEGF injections for ME was 5.3 ± 3.7 during the follow-up period. In total, 49 (32.7%) patients exhibited a very poor final VA; this group comprised significantly older patients with a significantly poorer baseline VA (P < 0.01 for both) than the control group. Comorbid internal carotid artery disease and diabetic retinopathy were significantly associated with a poor final VA. In actual clinical practice, visual outcomes may be extremely poor despite ME treatment in certain patients with CRVO, with advanced age, poor baseline VA, and comorbid internal carotid artery disease and diabetic retinopathy being significant risk factors

Foveal Thickness Fluctuation in Anti-VEGF Treatment for Branch Retinal Vein Occlusion: A Long-term Study

PURPOSE: Branch retinal vein occlusion (BRVO) causes macular edema (ME), which can be controlled with anti-VEGF treatments. However, these treatments are not curative, necessitating additional anti-VEGF treatments at recurrence. Long-term results, optimal anti-VEGF treatment regimens, and the comprehensive effects of ME recurrence are largely unknown. Thus, we aimed to examine the effects of foveal thickness (FT) fluctuation (FTF) on the visual and morphologic outcomes of anti-VEGF treatments for BRVO-ME administered via a pro re nata regimen. DESIGN: A retrospective, observational case series. SUBJECTS: This study analyzed 309 treatment-naïve patients (309 eyes) with BRVO-ME between 2012 and 2021 at a multicenter retinal practice. METHODS: The FT was assessed using OCT at each study visit. MAIN OUTCOME MEASURES: We evaluated the logarithm of the minimal angle of resolution (logMAR) best corrected visual acuity (BCVA) and the defect length of the foveal ellipsoid zone (EZ) band using OCT. RESULTS: At baseline, the mean logMAR BCVA was 0.30 ± 0.30 and the mean FT was 503 ± 162 μm. The number of anti-VEGF injections for BRVO-ME was 5.8 ± 4.6 during the mean follow-up period (50.6 ± 22.2 months). At the final examination, the mean logMAR BCVA and FT values were significantly improved compared with those at the baseline. Multiple regression analyses showed that age, baseline logMAR BCVA, and FTF were significantly associated with the final logMAR BCVA (β = 0.20, 0.35, and 0.30, respectively). Foveal thickness fluctuation (divided into groups 0-3 in ascending order of FTF) was significantly associated with logMAR BCVA and the defect length of the foveal EZ band at the final examination. The defect lengths of the foveal EZ band were longitudinally shortened in groups 0 and 1 and were slightly prolonged in groups 2 and 3. The logMAR BCVA showed improvements in groups 0 and 1 and worsened slightly in groups 2 and 3. CONCLUSIONS: Foveal thickness fluctuation was significantly associated with visual acuity and foveal photoreceptor status. Thus, the morphologic and functional prognoses of eyes with BRVO may improve with the identification of the characteristics of eyes with greater FTF and consequently controlling the FTF more strictly