Visual functions and multimodal imaging of patients with idiopathic focal choroidal excavation.

This study aimed to evaluate visual function and perform multimodal imaging on patients with focal choroidal excavation without any chorioretinal disease (idiopathic focal choroidal excavation [iFCE]). Seventeen eyes of 15 patients with iFCE (8 men, 7 women; mean ± standard deviation age, 56.0 ± 10.8 years) were assessed for visual function including visual acuity, metamorphopsia, aniseikonia, and retinal sensitivity. Multimodal imaging included optical coherence tomography (OCT), fundus autofluorescence (FAF), and OCT angiography. This study found that the maximum width and depth of the excavation were 597 ± 330 (238-1809) µm and 123 ± 45 (66-231) µm, respectively, and that FAF showed normal or hypoautofluorescence corresponding to iFCE. The fundus examination findings were stable during the follow-up period (96 ± 48 months). None of the eyes showed any abnormalities in central retinal sensitivity or aniseikonia. Metamorphopsia was detected using Amsler grid testing and M-CHARTS in two eyes. Therefore, this study is the first to quantitatively and qualitatively study metamorphopsia of patients with iFCE. Our results showed that most patients with iFCE did not have visual impairments, despite the presence of morphological changes in the outer retina and choroid.

Investigation of factors that may affect the foveal avascular zone: An optical coherence tomography angiography study.

SIGNIFICANCE: An understanding of factors that affect the foveal avascular zone (FAZ) in healthy eyes may aid in the early identification of patients at risk of retinal pathology, thereby allowing better management and preventive measures to be implemented. PURPOSE: The size and shape of the FAZ can change due to retinal diseases associated with oxidative stress, including diabetic retinopathy, glaucoma, and macular degeneration. This study aimed to assess the relationship, if any, between factors that may affect the superficial FAZ (i.e., vessel density, vessel perfusion, overweight/obesity) and possible links with macular pigment optical density in young, healthy participants. METHODS: One hundred thirty-nine participants aged 18 to 35 years were recruited to this cross-sectional study. The superficial FAZ area, foveal vascularity, and central macular thickness (CMT) were assessed using the Cirrus 5000. Health parameters, body mass index, trunk fat %, and macular pigment were analyzed to determine possible associations with the superficial FAZ. RESULTS: Mean FAZ area was 0.23 ± 0.08 mm2. Females had a significantly larger mean FAZ area than males (p=0.002). The FAZ area was positively correlated with body mass index (Pearson's r = 0.189, p=0.026). Significant correlates of the FAZ area in the multivariate model included vessel perfusion (central), CMT, and trunk fat %, collectively explaining 65.1% of the overall variability. CONCLUSIONS: Study findings suggest that reduced vessel perfusion, thinner CMT, and higher trunk fat % are plausible predictors of a larger FAZ area in healthy Caucasian adults. Low macular pigment optical density was, however, not associated with increased FAZ size in young healthy eyes. Noninvasive optical coherence tomography angiography testing, in association with these predictors, may aid in the early detection and monitoring of retinal diseases associated with oxidative stress.

Swept-source optical coherence tomography and swept-source optical coherence tomography angiography findings in circumscribed choroidal hemangioma before and after transpupillary thermotherapy.

PURPOSE: To investigate the swept-source optical coherence tomography (SS-OCT) and SS-OCT angiography (SS-OCTA) findings in circumscribed choroidal hemangioma (CCH) before and after treatment with transpupillary thermotherapy (TTT). METHODS: The clinical records of 21 eyes having CCH imaged with SS-OCT/SS-OCTA between September 2018 and December 2022 were evaluated. RESULTS: SS-OCT examination in CCH showed dome-shaped appearance (100%), choroidal shadowing (100%), expansion of choroidal structures (100%), subretinal fluid (66.7%), intraretinal edema/schisis (33.3%), retinal pigment epithelium (RPE) atrophy (19.0%), hyperreflective dots (19.0%), and epiretinal membrane (4.8%). Internal arborizing tumor vessels showing hyperreflectivity were observed in the choriocapillaris slab on SS-OCTA in all eyes. In the deep capillary plexus (DCP), flow void changes were seen in 7 eyes with intraretinal schisis/cystoid macular edema. Four CCHs > 2 mm in thickness showed outer retinal involvement due to unmasking of flow in intratumoral vessels related to RPE atrophy. Following TTT/indocyanine green-enhanced TTT (ICG-TTT) of CCH, SS-OCT findings included total/partial resolution of subretinal fluid (57.1%), complete/partial regression of the tumor (52.4%), and RPE atrophy (33.3%). After treatment; loss of choriocapillaris, decrease in tumor vascularity together with increase in the fibrous component and flow void areas were detected on SS-OCTA. CONCLUSIONS: SS-OCT/SS-OCTA are useful non-invasive tools for imaging the structural/vascular changes in CCHs managed with TTT or ICG-TTT. On SS-OCTA, hyporeflective spaces localizing to edema/schisis in the DCP and arborizing tumor vessels within a hyporeflective stromal background in the choriocapillaris slab were observed. After TTT/ICG-TTT, a decrease in tumor vessels and an increase in the fibrous component and flow-void areas inside the CCH were detected on SS-OCTA.

Intereye Microvascular Differences in Patients With Same-Stage Diabetic Retinopathy Revealed by OCTA.

Purpose: To evaluate microvascular intereye differences in diabetic patients with same-stage diabetic retinopathy (DR) in both eyes as assessed using optical coherence tomography angiography (OCTA). Methods: In this cross-sectional study, fovea-centered swept-source 6 × 6 mm OCTA scans were acquired using a 200 kHz OCTA device. Vessel density (VD) and fractal dimension were calculated on binarized, vessel-segmented images in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Foveal avascular zone (FAZ) area (FAZA) and perimeter (FAZP) was measured and FAZ circularity (FAZC) calculated. Absolute difference (δabs) and asymmetry index between eyes was assessed and compared across DR stages. Differences of VD, FD, and FAZ parameters between left and right eye were evaluated using linear mixed models. Results: A total of 336 eyes of 168 diabetic patients without DR and with DR stages ranging from mild nonproliferative to proliferative DR were included for analysis. The intereye comparison revealed significantly lower VD in the SCP (estimate [95% CI] = -0.009 [-0.01; -0.006], P < 0.01), as well as a significantly lower FD in the SCP (-0.007 [-0.009; -0.005], P < 0.01) of the left compared to the right eye. FAZC of the left compared to the right eye was lower in eyes without DR, moderate DR, and PDR (P < 0.05). FAZ δabs and asymmetry index were higher in more advanced disease stages (P < 0.05). Conclusions: OCTA metrics provide important information on the retinal microvasculature in systemic diseases such as DR. Our results reveal a significant intereye difference with lower VD and FD in the SCP as well as higher FAZ impairment of the left compared to the right eye.

Peripapillary hyperreflective ovoid mass-like structures with cystoid macular edema: a case report.

BACKGROUND: Peripapillary hyperreflective ovoid mass-like structures (PHOMS) are newly characterized lesions wedged around the optic discs, which used to be misdiagnosed. Better understanding and identifying PHOMS are important for monitoring the condition of optic nerve. CASE PRESENTATION: A young female presented to the ophthalmic clinic with blurred vision of both eyes. Protrusions resembling "C-shaped donut" were found circling the optic discs bilaterally. These lesions were homogenous hyperreflective on OCT, while they were also hypoautofluorescent and hypoechogenic. Meanwhile, cystoid macular edema (CME) was also identified in both eyes. The patient was then diagnosed as PHOMS with CME. A short-term glucocorticoids therapy was prescribed systemically. The logMAR best-corrected visual acuity (BCVA) of both eyes reached 0.0 in 4 months with recovery of CME, while the PHOMS remained. CONCLUSIONS: There is currently no report on PHOMS with CME. More attentions should be paid to PHOMS, for they are potential biomarkers for axoplasmic stasis involved in different diseases of the optic nerve.

Detection of capillary abnormalities in early diabetic retinopathy using scanning laser ophthalmoscopy and optical coherence tomography combined with adaptive optics.

This study tested if a high-resolution, multi-modal, multi-scale retinal imaging instrument can provide novel information about structural abnormalities in vivo. The study examined 11 patients with very mild to moderate non-proliferative diabetic retinopathy (NPDR) and 10 healthy subjects using fundus photography, optical coherence tomography (OCT), OCT angiography (OCTA), adaptive optics scanning laser ophthalmoscopy (AO-SLO), adaptive optics OCT and OCTA (AO-OCT(A)). Of 21 eyes of 11 patients, 11 had very mild NPDR, 8 had mild NPDR, 2 had moderate NPDR, and 1 had no retinopathy. Using AO-SLO, capillary looping, inflections and dilations were detected in 8 patients with very mild or mild NPDR, and microaneurysms containing hyperreflective granular elements were visible in 9 patients with mild or moderate NPDR. Most of the abnormalities were seen to be perfused in the corresponding OCTA scans while a few capillary loops appeared to be occluded or perfused at a non-detectable flow rate, possibly because of hypoperfusion. In one patient with moderate NPDR, non-perfused capillaries, also called ghost vessels, were identified by alignment of corresponding en face AO-OCT and AO-OCTA images. The combination of multiple non-invasive imaging methods could identify prominent microscopic abnormalities in diabetic retinopathy earlier and more detailed than conventional fundus imaging devices.

Associations of retinal microvascular alterations with diabetes mellitus: an OCTA-based cross-sectional study.

BACKGROUND: Diabetes, a health crisis afflicting millions worldwide, is increasing rapidly in prevalence. The microvascular complications triggered by diabetes have emerged as the principal cause of renal disease and blindness. The retinal microvascular network may be sensitive to early systemic vascular structural and functional changes. Therefore, this research endeavored to discern the systemic determinants influencing the retinal microvascular network in patients with and without diabetes. METHODS: The Kailuan Eye Study is a cross-sectional study based on the community-based cohort Kailuan Study. Participants underwent optical coherence tomography angiography (OCTA) (Zeiss Cirrus 5000; Carl Zeiss Meditec) and comprehensive systemic examination. Metrics such as perfusion density (PD), vascular density (VD), foveal avascular zone (FAZ) parameters of the superficial capillary plexus (SCP) in the macula were assessed. RESULTS: This study included 860 eligible participants (average age = 62.75 ± 6.52 years; 21.9% female), of which 449 were diabetics. People with diabetes had diminished PD and VD in the entire macular and parafoveal regions compared to people without diabetes. Reduced PD in the whole macular region was correlated with higher fasting plasma glucose (FPG, mmol/L) concentration (Beta = -0.19, 95% CI = -0.42 to -0.36, P < 0.001), longer axial length (AL, mm) (Beta = -0.13, 95%CI = -0.48 to -0.25, P = 0.002), and elevated heart rate (Beta = -0.10, 95%CI = -0.14 to -0.19, P = 0.014), after adjusting for younger age (Beta = -0.18, 95%CI = -0.24 to -0.35, P < 0.001), consistent with VD of the whole macular region. A higher FPG level was significantly correlated with lower SCP density of both PD and VD in the macular and parafoveal region (P < 0.05 for all), as well as increased systolic blood pressure and low-density lipoprotein cholesterol concentration (P < 0.01 for all). CONCLUSIONS: In this large-sample cross-sectional study, OCTA evaluation revealed that high prevalence of diabetes and elevated FPG levels were correlated with reduced retinal VD and PD. Hypertension and hyperlipidemia are important risk factors for the development of atherosclerotic cardiovascular disease but have no significant effect on retinal microvascular abnormalities.

High-resolution adaptive optics-trans-scleral flood illumination (AO-TFI) imaging of retinal pigment epithelium (RPE) in central serous chorioretinopathy (CSCR).

This study aims to correlate adaptive optics-transscleral flood illumination (AO-TFI) images of the retinal pigment epithelium (RPE) in central serous chorioretinopathy (CSCR) with standard clinical images and compare cell morphological features with those of healthy eyes. After stitching 125 AO-TFI images acquired in CSCR eyes (including 6 active CSCR, 15 resolved CSCR, and 3 from healthy contralateral), 24 montages were correlated with blue-autofluorescence, infrared and optical coherence tomography images. All 68 AO-TFI images acquired in pathological areas exhibited significant RPE contrast changes. Among the 52 healthy areas in clinical images, AO-TFI revealed a normal RPE mosaic in 62% of the images and an altered RPE pattern in 38% of the images. Morphological features of the RPE cells were quantified in 54 AO-TFI images depicting clinically normal areas (from 12 CSCR eyes). Comparison with data from 149 AO-TFI images acquired in 33 healthy eyes revealed significantly increased morphological heterogeneity. In CSCR, AO-TFI not only enabled high-resolution imaging of outer retinal alterations, but also revealed RPE abnormalities undetectable by all other imaging modalities. Further studies are required to estimate the prognosis value of these abnormalities. Imaging of the RPE using AO-TFI holds great promise for improving our understanding of the CSCR pathogenesis.

Lipid profile alterations in non-infectious uveitis: correlation with quantitative optical coherence tomography angiography parameters.

BACKGROUND/AIMS: Lipid profiles have been changed in numerous chronic conditions. The impact of uveitis on lipid metabolism remains unclear. METHODS: This is a cross-sectional study included 416 patients with non-infectious uveitis (NIU) and 416 healthy subjects. Standard techniques were used to measure total cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDLc), low-density lipoprotein-cholesterol (LDLc) levels. Quantitative optical coherence tomography angiography (OCTA) parameters were obtained from 500 eyes in each group. Correlation analysis examined the relationship between lipid profile and OCTA parameters. RESULTS: Patients with NIU exhibited significantly elevated TC, TG and LDLc levels compared with controls (p=0.003; p<0.001; p<0.001, respectively). Subgroup analysis revealed that HDLc was significantly lower in Behçet's disease (p=0.024) compared with controls. Vascular density (VD) in the superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaris and optic disk were significantly decreased in NIU eyes (p<0.05, respectively) compared with controls. HDLc exhibited a significant negative correlation with VDs in the whole and parafovea SCP (r=-0.489, p=0.008; r=-0.480, p=0.0026, respectively), while LDLc showed a significant positive correlation with VDs in the whole and parafovea DCP in NIU patients (r=0.576, p=0.032; r=0.267, p=0.034, respectively). CONCLUSIONS: The lipid profile is altered in NIU, and there are correlations between HDLc and LDLc levels and VD as measured by OCTA. Lipid profile analysis may offer valuable insights into evaluating vascular and metabolic aspects of NIU.

Double-dose investigation of aflibercept in neovascular age-related macular degeneration (DIANA): a real-world study.

BACKGROUND: To investigate the clinical effects of double-dose (4 mg) aflibercept treatment in neovascular age-related macular degeneration (nAMD), compared with the standard-dose (2 mg) treatment. METHODS: A total of 108 eyes from 97 patients with nAMD and received intravitreal aflibercept 2 mg and/or 4 mg treatment were retrospectively reviewed. The changes of central macular thickness (CMT)/ pigmental epithelium detachment height and the recurrence rate of exudation during the 12-month follow-up were compared between the 2 mg group and the 4 mg group. Self-control comparisons (2 mg switch to 4 mg) were also made between two regimens. RESULTS: Compared with the 2 mg group, tendencies of lower intraretinal fluid incidence and more CMT reduction were observed in the 4 mg group. The later one was also observed when eyes switching from 2 mg to 4 mg regimen. The median remission interval was 5 months in the 4 mg group, 2 months longer than the 3 months in the 2 mg group (P = 0.452). Injections needed in the 4 mg group were 3.644 ± 1.670, less than the 4.286 ± 2.334 injections in the 2 mg group within 12 months as well (P = 0.151). However, no associated vision benefits were gained from the double-douse regimen. No markedly increased-intraocular pressure events, or other adverse events were found in two groups. CONCLUSIONS: Compared to the aflibercept 2 mg treatment in nAMD, tendencies of anatomic gains and relieving treatment burden were brought by the aflibercept 4 mg treatment. This study may have additional importance, given the further application of high-dose aflibercept in real-world settings.

Filamentous RPE Hyperplasia in Combined Hamartoma of the Retina and RPE.

This case report describes a diagnosis of combined hamartoma of the retina and retinal pigment epithelium (RPE) with filamentous RPE hyperplasia in a female child with a history of amblyopia, myopia, and exotropia of the affected eye.

Fluorescein Angiography of Floating Retinal Veins.

This case report describes a diagnosis of floating retinal veins in a patient aged 4 years with a history of stage 2 familial exudative vitreoretinopathy.

Correlation between vessel density and thickness in the retina and choroid of severe non-proliferative diabetic retinopathy patients.

Objectives: To explore the correlation between the vessel density (VD) of the retina and choroid vascular plexuses and the thicknesses of their respective retinal layers and choroid membranes in participants with severe non-proliferative diabetic retinopathy (NPDR). Methods: We retrospectively analyzed the data of 42 eyes of 42 participants with diabetes mellitus (DM) and severe NPDR. In addition, 41 eyes of 41 healthy controls were evaluated. Measurements were taken for both groups using optical coherence tomography angiography (OCTA), including the area and perimeter of the foveal vascular zone (FAZ) and the vascular density (VD) in the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choroid capillary (CC). These measurements were compared with the retinal thickness (RT) of the inner/intermediate retinal layers and choroidal thickness (CT). The study evaluated the correlation between RT or CT and VD in the respective vascular networks, namely superficial capillary plexus (SCP), deep capillary plexus (DCP), or CC. Results: The inner RT and VD in all plexuses were significantly lower in the severe NPDR group than in the healthy controls. Furthermore, the FAZ area and perimeter were larger in the severe NPDR group. Inner RT was correlated with VD in the SCP group (r=0.67 and r=0.71 in the healthy control and severe NPDR groups, respectively; p<0.05). CT negatively correlated with VD in the CC (r=-0.697 and r=-0.759 in the healthy control and severe NPDR groups, respectively; p<0.05). Intermediate RT significantly correlated with VD in the DCP of the severe NPDR group (r=-0.55, p<0.05), but not in the healthy control group. Conclusions: Retinal or choroidal thickness strongly correlated with VD. Therefore, patients with severe NPDR must consider the distinct anatomical and functional entities of the various retinal layers and the choroid.

Study protocol: optical coherence tomography angiography for the detection of neovascular age-related macular degeneration: a comprehensive multicentre diagnostic accuracy study in the UK-the ATHENA study.

INTRODUCTION: The diagnosis of neovascular age-related macular degeneration (nAMD), the leading cause of visual impairment in the developed world, relies on the interpretation of various imaging tests of the retina. These include invasive angiographic methods, such as Fundus Fluorescein Angiography (FFA) and, on occasion, Indocyanine-Green Angiography (ICGA). Newer, non-invasive imaging modalities, predominately Optical Coherence Tomography (OCT) and Optical Coherence Tomography Angiography (OCTA), have drastically transformed the diagnostic approach to nAMD. The aim of this study is to undertake a comprehensive diagnostic accuracy assessment of the various imaging modalities used in clinical practice for the diagnosis of nAMD (OCT, OCTA, FFA and, when a variant of nAMD called Polypoidal Choroidal Vasculopathy is suspected, ICGA) both alone and in various combinations. METHODS AND ANALYSIS: This is a non-inferiority, prospective, randomised diagnostic accuracy study of 1067 participants. Participants are patients with clinical features consistent with nAMD who present to a National Health Service secondary care ophthalmology unit in the UK. Patients will undergo OCT as per standard practice and those with suspicious features of nAMD on OCT will be approached for participation in the study. Patients who agree to take part will also undergo both OCTA and FFA (and ICGA if indicated). Interpretation of the imaging tests will be undertaken by clinicians at recruitment sites. A randomised design was selected to avoid bias from consecutive review of all imaging tests by the same clinician. The primary outcome of the study will be the difference in sensitivity and specificity between OCT+OCTA and OCT+FFA (±ICGA) for nAMD detection as interpreted by clinicians at recruitment sites. ETHICS AND DISSEMINATION: The study has been approved by the South Central-Oxford B Research Ethics Committee with reference number 21/SC/0412.Dissemination of study results will involve peer-review publications, presentations at major national and international scientific conferences. TRIAL REGISTRATION NUMBER: ISRCTN18313457.

Patterns of Progression of Nonproliferative Diabetic Retinopathy Using Non-Invasive Imaging.

Purpose: To identify progression of nonproliferative diabetic retinopathy (NPDR) in patients with type 2 diabetes by combining optical coherence tomography angiography (OCTA) metrics and color fundus photography (CFP) images. Methods: This study was a post hoc analysis of a prospective longitudinal cohort study (CORDIS, NCT03696810) with 2-year duration. This study enrolled 122 eyes. Ophthalmological examinations included OCTA and CFP. OCTA metrics included skeletonized vessel density (SVD) and perfusion density (PD) at the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Microaneurysm turnover analysis and Early Treatment Diabetic Retinopathy Study (ETDRS) grading for diabetic retinopathy (DR) severity assessment were performed on 7-field CFP. Results: Eyes graded as ETDRS level 20 showed significant capillary nonperfusion predominantly in the inner ring area in the SCP (P < 0.001), whereas eyes graded as ETDRS level 35 and ETDRS levels 43 and 47 showed significant capillary nonperfusion in both the SCP and DCP in both inner and outer rings (P < 0.001). When evaluating rates of progression in capillary nonperfusion for the 2-year period of follow-up, changes were found predominantly in the DCP for SVD and PD and were better identified in the outer ring area. Microaneurysm turnover contributes to the characterization of NPDR progression by discriminating ETDRS level 35 from ETDRS levels 43 and 47 (P < 0.001), which could not be achieved using only OCTA metrics. Conclusions: Patterns of progression of NPDR can be identified combining OCTA examinations of the superficial and deep retinal capillary plexi of central retina and determination of microaneurysm turnover from fundus photographs. Translational Relevance: Our study reports results from a registered clinical trial that advances understanding of disease progression in NPDR.

Atypical acquired toxoplasmosis.

A 33-year-old male presented with unilateral painless vision loss with a history of sub-tenon steroid for the same. The fundus showed an elevated focus of retinochoroiditis with vitritis. On investigating for the cause, polymerase chain reaction test on the anterior chamber tap was found to be positive for Toxoplasma. Such confusing and atypical cases usually produce a clinical dilemma and should be managed in a stepwise manner. Ancillary investigations usually provide a clue to the clinician and should be performed without any hesitation.

Genotypic and Phenotypic Characterization of a Cohort of Patients Affected by Rod Cyclic Nucleotide Channel-Associated Retinitis Pigmentosa.

INTRODUCTION: Retinitis pigmentosa (RP), a heterogeneous inherited retinal disorder causing gradual vision loss, affects over 1 million people worldwide. Pathogenic variants in CNGA1 and CNGB1 genes, respectively, accounting for 1% and 4% of cases, impact the cyclic nucleotide-gated channel in rod photoreceptor cells. The aim of this study was to describe and compare genotypic and clinical characteristics of a cohort of patients with CNGA1- or CNGB1-related RP and to explore potential genotype-phenotype correlations. METHODS: The following data from patients with CNGA1- or CNGB1-related RP, followed in five Italian inherited retinal degenerations services, were retrospectively collected: genetic variants in CNGA1 and CNGB1, best-corrected visual acuity (BCVA), ellipsoid zone (EZ) width, fundus photographs, and short-wavelength fundus autofluorescence (SW-AF) images. Comparisons and correlation analyses were performed by first dividing the cohort in two groups according to the gene responsible for the disease (CNGA1 and CNGB1 groups). In parallel, the whole cohort of RP patients was divided into two other groups, according to the expected impact of the variants at protein level (low and high group). RESULTS: In total, 29 patients were recruited, 11 with CNGA1- and 18 with CNGB1-related RP. In both CNGA1 and CNGB1, 5 novel variants in CNGA1 and 5 in CNGB1 were found. BCVA was comparable between CNGA1 and CNGB1 groups, as well as between low and high groups. CNGA1 group had a larger mean EZ width compared to CNGB1 group, albeit not statistically significant, while EZ width did not differ between low and high groups A statistically significant correlation between EZ width and BCVA as well as between EZ width and age were observed in the whole cohort of RP patients. Fundus photographs of all patients in the cohort showed classic RP pattern, and in SW-AF images an hyperautofluorescent ring was observed in 14/21 patients. CONCLUSION: Rod CNG channel-associated RP was demonstrated to be a slowly progressive disease in both CNGA1- and CNGB1-related forms, making it an ideal candidate for gene augmentation therapies.

Investigating the Impact of Bariatric Surgery on Macular and Peripapillary Vessel Density in Obese Individuals without Metabolic Disease.

INTRODUCTION: It is well established that microvascular structures are affected in obese people with metabolic disease. We aimed to evaluate the effect on microvascular structures by examining macular and peripapillary vessel density with optical coherence tomography angiography after bariatric surgery in obese individuals without metabolic disease. METHODS: This prospective study included 96 eyes of 48 obese patients. Body mass index (BMI), macular vessel density in the superficial, intermediate, and deep capillary plexus, and peripapillary vessel density were measured before and 6 months after bariatric surgery. RESULTS: BMI decreased significantly to 43.75 ± 4.4 kg/m2 postoperatively compared to 55.31 ± 5.1 kg/m2 preoperatively (p < 0.05). A significant increase was observed in macular vessel density in the deep capillary plexus postoperatively (p < 0.01). However, no significant postoperative increase occurred in macular vascular density in the superficial and intermediate capillary plexus (p > 0.05). Moreover, there was no change in peripapillary vascular density (p > 0.05). Postoperative thickening of the foveal, parafoveal, and perifoveal retinal layers was significant (p < 0.001). No significant correlation was detected between BMI change and macular and peripapillary vessel density changes (p > 0.05). CONCLUSION: An increase in macular vascular density, particularly in the deep capillary plexus, and retinal layer thickness has been observed following bariatric surgery performed on obese individuals without metabolic disease. This increase may indicate that microvascular structures are affected even in the absence of metabolic disease and that microperfusion improves with surgery.

Laser speckle flowgraphy has comparable accuracy to indocyanine green fluorescence angiography in assessing bowel blood perfusion.

PURPOSE: To investigate the accuracy of laser speckle flowgraphy (LSFG), a noninvasive method for the quantitative evaluation of blood flow using mean blur rate (MBR) as a blood flow parameter in the assessment of bowel blood perfusion compared to indocyanine green fluorescence angiography (ICG-FA). METHODS: We enrolled 46 patients who underwent left-sided colorectal surgery. LSFG and ICG-FA were applied to assess blood bowel perfusion, with MBR and luminance as parameters, respectively. In both measurement methods, the position where the parameter suddenly decreased was defined as the blood flow boundary line. Subsequently, the blood flow boundaries created after processing the blood vessels flowing into the intestinal tract were determined using LSFG and ICG-FA, and concordance between the two was examined. Blood flow boundaries were visually identified using color tone changes on a color map created based on MBR in LSFG and using differences in luminance in ICG-FA. The distances between the transection line and blood flow boundaries determined using each method were compared. RESULTS: The location of blood flow boundaries matched in 65% (30/46) of cases. Although locations differed in the remaining 35% (16/46), all were located on the anal side near the transection line, and the difference was not clinically significant. The average distances between the transection line and blood flow boundary were 2.76 (SD = 3.25) and 3.71 (SD = 4.26) mm, respectively. There was no statistically significant difference between the two groups (p = 0.38). CONCLUSION: LSFG was shown to have comparable accuracy to ICG-FA, and may be useful for evaluating bowel perfusion.