Optical Coherence Tomography Analysis Research Articles

Structural and functional characterization of retinal impairment in T1DM patients without diabetic retinopathy: a 3-year longitudinal study.

To analyze the progression of structural and functional retinal impairment in type 1 diabetes mellitus (T1DM) patients with no clinical signs of diabetic retinopathy (DR) during a 3-year follow-up. This was an observational longitudinal study. Post-pediatric T1DM patients without clinical signs of DR, and sex- and age-matched healthy subjects were recruited at San Raffaele Hospital (Milan, Italy). Each patient underwent a comprehensive ophthalmological evaluation, including optical coherence tomography (OCT), OCT-angiography (OCT-A), retinal static and dynamic vessel analysis (DVA), and microperimetry. 21 eyes of 21 T1DM patients (10 females; 24 ± 2years old), and 21 age and sex-matched healthy subjects were enrolled. At baseline, T1DM eyes revealed a significantly decreased vessel length density using OCT-A (p < 0.001 and p = 0.046 in 3 × 3 and 6 × 6mm images) and a significantly increased vessel density index (p = 0.013 and p = 0.087 in 3 × 3 and 6 × 6mm images) of deep capillary plexus. DVA detected a significantly decreased vessel response to flicker light (p = 0.002). A significantly increased thickness of ganglion cellular layer 6-mm-diameter subfields in inferior and superior quadrants was found in diabetic patients (p < 0.001 in both subfields). At 3-years-follow-up no significant longitudinal changes were disclosed in all analyses. Concomitant subclinical microvascular and neurodegenerative damages could be early signs of DR onset that precede functional alterations and clinical signs of DR development. These alterations demonstrated a stable trend over time.

Peripapillary Retinoschisis in Glaucoma: A Systematic Review.

Peripapillary retinoschisis may bias optical coherence tomography's monitoring of glaucoma progression. Its impact on glaucoma still remains uncertain. Only two out of the ten included studies illustrated a correlation between peripapillary retinoschisis and glaucoma progression. The frequent use of optical coherence tomography increased the detection of peripapillary retinoschisis, which poses challenges in the follow-up of glaucoma patients. This systematic review aims to summarize the literature regarding peripapillary retinoschisis in glaucoma, exploring its prevalence, impact on disease, and clinical management implications. We searched PubMed, Embase, Web of Science and Scopus with tailored search queries for each platform. All studies had to report peripapillary retinoschisis in glaucoma patients. Exclusion criteria included studies with less than 10 eyes, studies focusing on schisis outside the disc area, with concomitant retinal or optic nerve lesions, with animals, reviews, studies written in non-English language and congress abstracts. Ten studies were included, of which 7 were case-control, one was a cohort study and two were case series.Six studies showed that peripapillary retinoschisis often overlapped pre-existing retinal nerve fiber layer defects. One study reported that the de novo development of peripapillary retinoschisis was more frequent in eyes with glaucoma progression than in eyes without progression.Visual field findings were inconsistent, with just one study (out of six) showing that glaucoma patients with peripapillary retinoschisis experienced faster visual field deterioration than those without it. Overall, solely two studies (out of seven) associated peripapillary retinoschisis with faster glaucoma progression. Peripapillary retinoschisis biases optical coherence tomography analysis in glaucoma. Caution is needed against overestimation of retinal nerve fiber layer thickness when peripapillary retinoschisis develops, and misinterpretation of its resolution as rapid progression. Peripapillary retinoschisis' exact impact on glaucoma progression remains unclear.

Segmentation and quantitative analysis of optical coherence tomography (OCT) images of laser burned skin based on deep learning

Evaluation of skin recovery is an important step in the treatment of burns. However, conventional methods only observe the surface of the skin and cannot quantify the injury volume. Optical coherence tomography (OCT) is a non-invasive, non-contact, real-time technique. Swept source OCT uses near infrared light and analyzes the intensity of light echo at different depths to generate images from optical interference signals. To quantify the dynamic recovery of skin burns over time, laser induced skin burns in mice were evaluated using deep learning of Swept source OCT images. A laser-induced mouse skin thermal injury model was established in thirty Kunming mice, and OCT images of normal and burned areas of mouse skin were acquired at day 0, day 1, day 3, day 7, and day 14 after laser irradiation. This resulted in 7000 normal and 1400 burn B-scan images which were divided into training, validation, and test sets at 8:1.5:0.5 ratio for the normal data and 8:1:1 for the burn data. Normal images were manually annotated, and the deep learning U-Net model (verified with PSPNe and HRNet models) was used to segment the skin into three layers: the dermal epidermal layer, subcutaneous fat layer, and muscle layer. For the burn images, the models were trained to segment just the damaged area. Three-dimensional reconstruction technology was then used to reconstruct the damaged tissue and calculate the damaged tissue volume. The average IoU value and f-score of the normal tissue layer U-Net segmentation model were 0.876 and 0.934 respectively. The IoU value of the burn area segmentation model reached 0.907 and f-score value reached 0.951. Compared with manual labeling, the U-Net model was faster with higher accuracy for skin stratification. OCT and U-Net segmentation can provide rapid and accurate analysis of tissue changes and clinical guidance in the treatment of burns.

Pharmacoeconomic evaluation of optical coherence tomography for imaging in cardiac interventions

Introduction: OCT is a noninvasive, contactless, optical method that uses infrared light to produce images of blood vessel anatomy, tissue microstructure, and stents during cardiac catheterization. Aim: This review aims to present a cost-effectiveness analysis and budget impact analysis of optical coherence tomography for imaging in patients undergoing cardiac catheterization and percutaneous coronary interventions. Methods: An incomplete economic analysis was chosen to evaluate the cost-effectiveness of OCT, in which only direct medical costs were assessed. The time horizon for estimating the costs and health bene&amp;#64257; ts of OCT was one year. In addition, a budget impact analysis was conducted. Results: As a result of the incomplete economic analysis of the costs of OCT-guided PCI, it could be seen that the total cost per patient amounted to BGN 4,954.89. These costs include the unit cost of the device (OCT catheters) &amp;ndash; BGN 2,000.00 including VAT, and the weighted average cost of the OCT-guided PCI procedure &amp;ndash; BGN 2,954.89. Conclusion: The OCT-guided PCI strategy is associated with higher procedural costs but with more favorable clinical bene&amp;#64257; ts, making it a cost-effective option for intravascular imaging in the long term.

Unveiling the Effects of Diabetes on Coronary Artery Disease Through Angiography

Background: Coronary artery disease (CAD) remains a leading cause of morbidity and mortality globally, particularly among patients with Type 2 Diabetes Mellitus (T2DM). Diabetic patients are at a higher risk of developing CAD due to factors such as poor glycemic control, lipid metabolism abnormalities, and endothelial dysfunction. Prior studies have demonstrated that diabetic patients tend to present with more extensive coronary artery involvement and worse outcomes following cardiovascular interventions. Objective: This study aimed to assess the impact of T2DM on coronary angiography outcomes, specifically focusing on the incidence of multi-vessel disease and the severity of coronary artery stenosis. Methods: This observational cohort study was conducted at Lady Reding Hospital, a tertiary care center specializing in cardiovascular diseases. Participants were recruited from the outpatient cardiology clinic between January 2020 and January 2022. Inclusion criteria included patients aged 40 to 80 years undergoing coronary angiography for the first time due to suspected CAD. Exclusion criteria were previous coronary artery interventions, congenital heart disease, active infections, and renal insufficiency (creatinine &gt; 2.0 mg/dL). Baseline characteristics such as age, gender, BMI, hypertension status, and smoking history were collected. Diabetes status was confirmed via HbA1c levels (≥6.5%). Coronary angiography was performed using standard techniques, with angiograms analyzed by two blinded cardiologists. Primary outcomes included the presence of multi-vessel disease (≥70% stenosis in two or more major coronary arteries) and the severity of stenosis (&gt;70% blockage). Additional assessments using Intravascular Ultrasound (IVUS) and Optical Coherence Tomography (OCT) evaluated plaque characteristics and vessel sizes in a subset of patients. Statistical analysis was performed using SPSS version 25.0, employing Chi-square tests for categorical variables, independent t-tests for continuous variables, and multivariable logistic regression to adjust for confounders. Results: The study included 300 participants, with 150 diabetic and 150 non-diabetic patients. Diabetic patients had a mean age of 62.3 ± 10.4 years, while non-diabetic patients had a mean age of 58.2 ± 9.8 years. The prevalence of hypertension was higher among diabetic patients (60%) compared to non-diabetic patients (40%). The incidence of multi-vessel disease was significantly higher in diabetic patients (70%) compared to non-diabetic patients (50%) (p &lt; 0.05). Severe stenosis was observed in 65% of diabetic patients versus 45% of non-diabetic patients (p &lt; 0.01). IVUS and OCT analyses showed a higher prevalence of lipid-rich plaques in diabetic patients (55% vs. 30%) and a smaller mean luminal diameter (2.8 ± 0.6 mm vs. 3.4 ± 0.5 mm). Conclusion: Diabetes significantly impacts the severity and extent of coronary artery disease, with diabetic patients exhibiting higher rates of multi-vessel disease and severe stenosis. Advanced imaging techniques highlighted distinct plaque characteristics in diabetic patients, underscoring the need for aggressive and personalized management strategies. These findings emphasize the importance of integrating advanced imaging and comprehensive management to mitigate cardiovascular risks in diabetic patients.

Unveiling Key Pathological Indicators for Disease Progression in Vogt Koyanagi Harada Disease and Sympathetic Ophthalmia Through Advanced Choroidal Volume Analysis

ABSTRACT Purpose To evaluate the association between quantitative parameters derived from volume analysis of optical coherence tomography (OCT) data and disease worsening in Vogt-Koyanagi-Harada disease (VKHD) and sympathetic ophthalmia (SO). Methods This retrospective study, conducted at Osaka University Hospital, employed swept-source OCT scans from patients diagnosed with VKHD or SO between October 2012 and January 2021. The choroidal vessel structure was segmented and visualized in three dimensions, generating quantitative vessel volume maps. Region-specific choroidal vessel volume (CVV), choroidal volume (CV), and vessel index (VI) were scrutinized for their potential correlation with disease severity. Results Thirty-five eyes of 18 VKHD and 2 SO patient (8 females, 10 males) were evaluated. OCT-derived CVV maps revealed regional CV alterations in VKHD and SO patients. Two parameters, i.e. CV at 3- and 6-month follow-ups (p = 0.044, p = 0.040, respectively, with area under the ROC curve of 0.70) and CVV at 6 months (p = 0.046, area under the ROC curve of 0.71), were significantly higher in recurrent VKHD and SO compared to effectively treated cases. Conclusions The volume analysis of OCT images facilitates a three-dimensional visualization of choroidal alterations, which may serve as a reflection of disease severity in VKHD and SO patients. Furthermore, noninvasive initial CVV or CV measurements may serve as potential biomarkers for predicting disease recurrence in VKHD and SO.

OCT analysis of preoperative foveal microstructure in recent-onset macula-off rhegmatogenous retinal detachment: visual acuity prognostic factors

BackgroundTo evaluate, in patients undergoing macula-off rhegmatogenous retinal detachment surgery (RRD), the correlation between preoperative optical coherence tomography (OCT) morphological features and postoperative visual acuity.MethodsRetrospective interventional non-randomised clinical trial on...

Complement inhibition treatment for geographic atrophy (GA): functional and morphological efficacy and relevant biomarkers in clinical practice

The approval of complement inhibitory therapeutic agents for the treatment of geographic atrophy (GA) has highlighted the need for reliable and reproducible measurement of disease progression and therapeutic efficacy. Due to its availability and imaging characteristics optical coherence tomography (OCT) is the method of choice. Using OCT analysis based on artificial intelligence (AI), the therapeutic efficacy of pegcetacoplan was demonstrated at the levels of both the retinal pigment epithelium (RPE) and photoreceptors (PR). Cloud-based solutions that enable monitoring of GA are already available.

OPTICAL COHERENCE TOMOGRAPHY ANALYSIS OF RETINAL THICKNESS IN COVID-19 PATIENTS

OBJECTIVE: The aim of this study was to perform Optical Coherence Tomography analysis of retinal changes in patients with COVID-19 infection and compare them with healthy controls. MATERIAL AND METHODS: For this purpose, 42 COVID-19 positive patients (group 1) and 44 healthy adults (group 2), aged between 18 and 68 years, who were admitted to our clinic between October 1, 2020 and May 1, 2021, were included in the study. Central foveal thickness, choroidal thickness (subfoveal) and peripapillary retinal nerve fiber thickness were measured. Measurements were performed at the central fovea and at 1500 μm nasal and 1500 μm temporal points from the central fovea. RESULTS: Age and gender distribution were similar in the groups (p=0.610 and p=0.992, respectively). However, central foveal thickness (p&amp;lt;0.001), subfoveal choroidal thickness (p=0.001) and peripapillary retinal nerve fiber layer thickness (p&amp;lt;0.001) were significantly different between the two groups. CONCLUSIONS: In conclusion, central fovea, subfoveal choroidal and peripapillary retinal nerve fiber layer thickness were higher in polymerase chain reaction positive COVID-19 patients compared to healthy controls. To understand the pathogenesis of systemic and local changes caused by COVID-19, multicenter and long-term studies with a large number of patient subgroups are necessary.

The relationship between complement C1q and coronary plaque vulnerability based on optical coherence tomography analysis

To determine the association between complement C1q and vulnerable plaque morphology among coronary artery disease (CAD) patients. We conducted a retrospective observational study of 221 CAD patients admitted to The Second Affiliated Hospital of Xi’an Jiaotong University. Intravascular optical coherence tomography was utilized to describe the culprit plaques’ morphology. Using logistic regression analysis to explore the correlation between C1q and vulnerable plaques, and receiver operator characteristic (ROC) analysis assess the predictive accuracy. As reported, the complement C1q level was lower in ACS patients than CCS patients (18.25 ± 3.88 vs. 19.18 ± 4.25, P = 0.045). The low complement-C1q-level group was more prone to develop vulnerable plaques. In lipid-rich plaques, the complement C1q level was positively correlated with the thickness of fibrous cap (r = 0.480, P = 0.041). Univariate and multivariate logistic regression analyses suggested that complement C1q could be an independent contributor to plaques’ vulnerability. For plaque rupture, erosion, thrombus, and cholesterol crystals, the areas under the ROC curve of complement C1q level were 0.873, 0.816, 0.785, and 0.837, respectively (P < 0.05 for all). In CAD patients, the complement C1q could be a valuable indicator of plaque vulnerability.

Characterization of central-involved diabetic macular edema using OCT and OCTA.

To characterize the occurrence of diabetic macular edema and the presence of abnormal retinal fluid accumulation in nonproliferative diabetic retinopathy (NPDR). In this two-year prospective study, a total of 122 eyes with diabetes type 2 underwent optical coherence tomography (OCT) and OCT-Angiography in association with OCT-Fluid imaging, a novel algorithm of OCT analysis allowing quantification of abnormal accumulation of fluid in the retina through low optical reflectivity ratios (LOR). Early Treatment Diabetic Retinopathy Study (ETDRS) grading for diabetic retinopathy (DR) severity assessment was performed using 7-field color fundus photography. Best corrected visual acuity was also recorded. During the 2-year follow-up, 23 eyes (19%) developed central-involved diabetic macular edema (CI-DME) and 2 eyes (2%) developed clinically significant macular edema (CSME). In the two-year period of the study, eyes that developed CI-DME showed a progressive increase in central retinal thickness (CRT) (β = 7.7 ± 2.1 µm/year, p < 0.001) and in LOR values (β = 0.009 ± 0.004 ratio/year, p = 0.027). The increase in CRT and abnormal retinal fluid, represented by increased LOR ratios, are associated with increased retinal perfusion in the deep capillary plexus (DCP) (skeletonized vessel density, p = 0.039). In contrast, the eyes with CSME showed decreased retinal perfusion and abnormal fluid located in the outer layers of the retina. CI-DME and CSME appear to represent different entities. Eyes with CI-DME show increases in abnormal retinal fluid associated with increased retinal vascular perfusion in the DCP. Eyes with CSME are apparently associated with decreased retinal vascular perfusion in the DCP and abnormal fluid in the outer retina.

Using optical coherence tomography to optimize Mohs micrographic surgery

Mohs micrographic surgery (MMS) is considered the gold standard for treating high-risk cutaneous basal cell carcinoma (BCC), but is expensive, time-consuming, and can be unpredictable as to how many stages will be required or how large the final lesion and corresponding surgical defect will be. This study is meant to investigate whether optical coherence tomography (OCT), a highly researched modality in dermatology, can be used preoperatively to map out the borders of BCC, resulting in fewer stages of MMS or a smaller final defect. In this prospective study, 22 patients with BCC undergoing surgical excision were enrolled at a single institution. All patients had previously received a diagnostic biopsy providing confirmation of BCC and had been referred to our center for excision with MMS. Immediately prior to performing MMS, OCT was used to map the borders of the lesion. MMS then proceeded according to standard protocol. OCT images were compared to histopathology for agreement. Histopathologic analysis of 7 of 22 MMS specimens (32%) revealed a total absence of BCC, indicating resolution of BCC after previous diagnostic biopsy. This outcome was correctly predicted by OCT imaging in 6 of 7 cases (86%). Nine tumors (9/22, 41%) had true BCC and required a single MMS stage, which was successfully predicted by pre-operative OCT analysis in 7 of 9 cases (78%). The final six tumors (27%) had true BCC and required two MMS stages for complete excision; preoperative OCT successfully predicted the need for a second stage in five cases (5/6, 83.3%). Overall, OCT diagnosed BCC with 95.5% accuracy (Cohen’s kappa, κ = 0.89 (p-value = < 0.01) in the center of the lesion. Following a diagnostic biopsy, OCT can be used to verify the existence or absence of residual basal cell carcinoma. When residual tumor is present that requires excision with MMS, OCT can be used to predict tumor borders, optimize surgery and minimize the need for additional surgical stages.

Inhibition of HDAC1 and 3 in the Presence of Systemic Inflammation Reduces Retinal Degeneration in a Model of Dry Age-Related Macular Degeneration.

Purpose: Previously, we identified increased retinal degeneration and cytokine response in a mouse model of dry age-related macular degeneration (AMD) in the presence of systemic inflammation from rheumatoid arthritis (RA). Histone deacetylases (HDACs) regulate cytokine production by reducing acetylation and are found to be dysregulated in inflammatory diseases, including RA and AMD. Therefore, this current study investigates the effect of HDAC inhibition on AMD progression in the presence of systemic inflammation. Methods: Collagen induced arthritis (CIA) was induced in C57BL6J mice, followed by sodium iodate (NaIO3)-induced retinal degeneration. Mice were treated with a selective HDAC class I inhibitor, MS-275, and retinal structure [optical coherence tomography (OCT)], function (electroretinography), and molecular changes quantitative real-time polymerase chain reaction (RT-qPCR, Western Blot) were assessed. Results: NaIO3 retinal damage was diminished in CIA mice treated with MS-275 (P ≤ 0.05). While no significant difference was observed in retinal pigment epithelium (RPE) function, a trend in increased c-wave amplitude was detected in CIA + NaIO3 mice treated with MS-275. Finally, we identified decreased Hdac1, Hdac3, and Cxcl9 expression in CIA + NaIO3 mouse RPE/choroid when treated with MS-275 (P ≤ 0.05). Conclusions: Our data demonstrate that HDAC inhibition can reduce the additive effect of NaIO3-induced retinal degeneration in the presence of systemic inflammation by CIA as measured by OCT analysis. In addition, HDAC inhibition in CIA + NaIO3 treated mice resulted in reduced cytokine production. These findings are highly innovative and provide additional support to the therapeutic potential of HDAC inhibitors for dry AMD treatment.

Trans-Synaptic Degeneration in the Visual Pathway in Patients With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease.

We aimed to assess the presence of retinal neurodegeneration independent of optic neuritis (ON) in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and to investigate the development of trans-synaptic anterograde degeneration in these patients after ON. Cross-sectional, retrospective study of 34 adult patients with MOGAD and 23 healthy controls (HC). Clinical, optical coherence tomography (OCT), and MRI data were collected. Peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell inner plexiform layer (GCIPL) were obtained using Heidelberg Spectralis. FreeSurfer7 was used to obtain the lateral geniculate nucleus (LGN), occipital volume fractions (to total estimated intracranial volume), and occipital cortical thickness. For the anterior visual pathway, the analysis was conducted using eyes, classified based on the history of ON (Eye-ON and Eye-NON) and compared with Eye-HC. The analysis of OCT and brain volumetric measures was conducted comparing MOGAD-ON, MOGAD-NON, and HC groups. The analysis of covariance with a Bonferroni-adjusted post hoc test was used to test differences between groups and linear regression analysis to evaluate OCT/MRI associations; age and sex were considered as covariates. 24 (70.5%) patients had a prior ON. Median pRNFL and GCIPL thickness (um) was significantly reduced in Eye-ON vs EyeNON and HC (pRNFL: 69.4 (17.3), 89.6 (13.7), 98.2 (11.7), p < 0.001; GCIPL: 55.8 (8.7), 67.39 (8.7), 72.6 (4.5), p < 0.001). pRNFL and GCIPL thickness had a negative correlation with the number of ON episodes (p = 0.025 and p = 0.031, respectively). LGN volume fraction was significantly lower in patients with MOGAD-ON than in HC (0.33 (0.05) vs 0.39 (0.04), p = 0.002). The occipital cortical thickness was lower in MOGAD-ON compared with MOGAD-NON and HC (p = 0.010). In patients with MOGAD-ON, pRNFL correlated with LGN volume (p = 0.006), occipital thickness (p = 0.002), and the medial occipital cortex (p = 0.002), but not the lateral occipital lobe. Compared with HC, MOGAD-ON exhibits reduced retinal thickness, primarily influenced by the presence and the number of prior ON episodes. Moreover, MOGAD-ON demonstrates significant atrophy in the retinal, subcortical, and cortical regions of the visual pathway, distinguishing them from MOGAD-NON and HC. These findings suggest that in patients with MOGAD neurodegeneration is tightly correlated with damage to the involved pathway.

Optical coherence tomography and gray scale digital analysis as noninvasive techniques for evaluating molar-incisor hypomineralization severity: A comparative study with microcomputed tomography.

Molar-incisor hypomineralization (MIH) is a qualitative defect of dental enamel characterized by demarcated opacities present in permanent first molars and other teeth. It is considered a major clinical challenge in dentistry because it makes affected teeth more susceptible to fractures and dental caries. Its diagnosis is mainly clinical and there are few technological resources that allow for a more accurate diagnosis, especially with respect to the depth of the defect in the dental enamel. In this context, optical coherence tomography (OCT), which is routinely used in ophthalmology, can produce images of the depth of the dental enamel, making it a promising method. In this study, 33 teeth with different MIH severities were evaluated using OCT and microcomputed tomography (microCT). Semi-quantitative methods of grayscale pattern analysis were used to compare images obtained from different severities of MIH with the mineral density obtained through microCT. MicroCT evaluation revealed that hypomineralized enamel had a significantly lower mineral density than intact enamel. However, this difference was not observed between the mild and severe MIH lesions. In the OCT evaluation, significant differences were observed between the intact and hypomineralized enamel, and the gray value comparison provided a method for quantitative differentiation between the two. This study suggests that OCT could be a useful adjunct to traditional diagnostic methods for MIH, offering a noninvasive approach to evaluate enamel defects. RESEARCH HIGHLIGHTS: Combining optical coherence tomography with grayscale digital analysis shows potential as a promising method for diagnosing molar-incisor hypomineralization and assessing its level of severity.

Elucidating the development of cooperative anode-biofilm-structures

Microbial electrochemical systems are a highly versatile platform technology with a particular focus on the interplay of chemical and electrical energy conversion and offer immense potential for a sustainable bioeconomy. The industrial realization of this potential requires a critical focus on biofilm optimization if performance is to be controlled over a long period of time. Moreover, the aspect and influence of cooperativity has to be addressed as many applied anodic bioelectrochemical systems will most likely be operated with a diversity of interacting microbial species. Hence, the aim of this study was to analyze how interspecies dependence and cooperativity of a model community influence the development of anodic biofilms. To investigate biofilm activity in a spatially resolved manner, a microfluidic bioelectrochemical flow cell was developed that can be equipped with user-defined electrode materials and operates under laminar flow conditions. With this infrastructure, the development of single and co-culture biofilms of the two model organisms Shewanella oneidensis and Geobacter sulfurreducens on graphite electrodes was monitored by optical coherence tomography analysis. The interdependence in the co-culture biofilm was achieved by feeding the community with lactate, which is converted by S. oneidensis into acetate, which in turn serves as substrate for G. sulfurreducens. The results show that co-cultivation resulted in the formation of denser biofilms than in single culture. Moreover, we hypothesize that S. oneidensis in return utilizes the conductive biofilm matrix build by G. sulfurreducens for direct interspecies electron transfer (DIET) to the anode. FISH analysis revealed that the biofilms consisted of approximately two-thirds G. sulfurreducens cells, which most likely formed a conductive 3D network throughout the biofilm matrix, in which evenly distributed tubular S. oneidensis colonies were embedded without direct contact to the anode surface. Live/dead staining shows that the outermost biofilm contained almost exclusively dead cells (98 %), layers near the anode contained 45–56 % and the entire biofilm contained 82 % live cells. Our results exemplify how the architecture of the exoelectrogenic biofilm dynamically adapts to the respective process conditions.

Optical coherence tomography angiography suggests choriocapillaris perfusion deficit as etiology of acute macular neuroretinopathy.

Acute macular neuroretinopathy (AMN) can cause sudden-onset and permanent scotoma in healthy young patients. Analysis of optical coherence tomography (OCT) and OCT angiography (OCTA) of AMN patients may provide insights into disease mechanism. We conducted a retrospective study of consecutive SARS-Cov-2-related AMN patients that presented in our clinic between Jan 1st, 2022, and April 30th, 2023, within 30days of symptom onset. Retinal vessel area density (VAD) of AMN lesions in OCTA was quantified and compared to an adjacent tissue control (ATC). This quantification was performed for the superficial vascular plexus (SVP), the intermediate capillary plexus (ICP), the deep capillary plexus (DCP), the choriocapillaris (CC), and choroid. Furthermore, en face OCT images were analyzed. Nine AMN patients were identified, 6 of these (4 female, 2 male, average age 25years) fulfilled the inclusion criteria and were included into this study. Average time from symptom onset to OCTA was 14.3days. No VAD differences between AMN and adjacent tissue were found in either retinal layer (SVP, ICP, DCP). In contrast, VAD in CC was reduced by 27% against the ATC (p = 0.007) and choroidal VAD was reduced by 41% (p = 0.017). Further analysis of en face OCT could show that the pathognomonic infrared hyporeflectivity in AMN is caused by photoreceptor alterations rather than changes in the inner retinal layers. Our data suggests that a perfusion deficit in the choroidal layers is responsible for AMN rather than in the DCP, which is the predominant hypothesis in current literature.

Contemporary status of diagnostic endoluminal ultrasound and optical coherence tomography in the ureter

AbstractObjectiveTo evaluate via a review of published literature, the efficacy of endoluminal ultrasound (ELUS) and optical coherence tomography (OCT) in the following ureteric diseases: urolithiasis, upper tract urothelial carcinoma, stricture disease and pelvic‐ureteric junction obstruction (PUJO).Patients and methodsUreteric high‐frequency ELUS provides 360° imaging, to a depth of 20 mm, and has been demonstrated to assess ureteric stricture length, degree of fibrosis and aetiology. OCT produces high‐quality images with a penetration depth of 2 mm. ELUS has proven to be useful at the time of endopyelotomy for PUJO as it can identify crossing vessels, some not detectable on CT angiography, allowing the urologist to avoid these when making their incision. Ureteric ELUS may be utilised for submucosal ureteric stones as they are highly visible. Endoluminal ultrasound may be deployed in the case of known sub‐mucosal urolithiasis when the ureter appears stone‐free. It may help identify sub‐mucosal stones or stones within diverticulum.ResultsEndoluminal ultrasound has been analysed for its use in determining muscle‐invasive urothelial carcinoma of the ureter. The PPV for ≥pT2 was only 16.7% in one study of six patients with MIBC and 76.2% in 21 patients with &lt;pT2 disease. Analysis of OCT for staging UTUC during ureteroscopy and biopsy demonstrated sensitivity for tumour invasion of 100% and specificity of 92%, 83% of lesion staging matched with histological analysis. Imaging analysis did not match histology in three patients with large exophytic tumours that exceeded the OCT depth penetration. Due to its superficial penetration, OCT cannot reliably stage large tumours.ConclusionsUreteric ELUS has been reported to be a useful tool in endopyelotomy, urolithiasis and stricture disease. The staging of ureteric urothelial carcinoma remains unsatisfactory with current imaging techniques and biopsy methods, and, based on the current literature, ELUS does not appear to have a strong enough PPV to determine muscle invasion. Ureteric OCT may be a useful tool in the future staging of upper tract urothelial carcinoma, particularly in differentiating the stage of small tumours. Further studies are needed in this area.

Acetylsalicylic acid use and development of cardiac allograft vasculopathy: A national prospective study using highly automated 3-D optical coherence tomography analysis.

There is conflicting evidence on the role of acetylsalicylic acid (ASA) use in the development of cardiac allograft vasculopathy (CAV). A nationwide prospective two-center study investigated changes in the coronary artery vasculature by highly automated 3-D optical coherence tomography (OCT) analysis at 1 month and 12 months after heart transplant (HTx). The influence of ASA use on coronary artery microvascular changes was analyzed in the overall study cohort and after propensity score matching for selected clinical CAV risk factors. In total, 175 patients (mean age 52±12 years, 79% male) were recruited. During the 1-year follow-up, both intimal and media thickness progressed, with ASA having no effect on its progression. However, detailed OCT analysis revealed that ASA use was associated with a lower increase in lipid plaque (LP) burden (p=.013), while it did not affect the other observed pathologies. Propensity score matching of 120 patients (60 patient pairs) showed similar results, with ASA use associated with lower progression of LPs (p=.002), while having no impact on layered fibrotic plaque (p=.224), calcification (p=.231), macrophage infiltration (p=.197), or the absolute coronary artery risk score (p=.277). According to Kaplan-Meier analysis, ASA use was not associated with a significant difference in survival (p=.699) CONCLUSION: This study showed a benefit of early ASA use after HTx on LP progression. However, ASA use did not have any impact on the progression of other OCT-observed pathologies or long-term survival.

Morphological characteristics of in-stent restenosis with different degrees of area stenosis: an optical coherence tomography study.

The morphological characteristics of in-stent restenosis (ISR) in relation to varying degrees of area stenosis have not been comprehensively examined. This study aimed to explore the tissue characteristics of patients experiencing ISR with different degrees of area stenosis through the utilization of optical coherence tomography (OCT). In total, 230 patients with ISR who underwent OCT were divided into the following three groups: area stenosis (AS) < 70% (n = 26); 70-80% (n = 119) and AS ≥ 80% (n = 85). Among the 230 patients, the clinical presentation as stable angina was 61.5% in AS < 70%, followed by 47.2% in 70% < AS ≤ 80%, and 31.8% in AS ≥ 80% (P = 0.010). The OCT findings showed that heterogeneous neointima, ISNA, LRP, neointima rupture, TCFA-like pattern, macrophage infiltration, red and white thrombus was more common with AS increased. Ordinal logistic regression analysis showed that higher AS was associated with previous dyslipidemia (odds ratio [OR], 4.754; 95% confidence interval [CI], 1.419-15.927, P = 0.011), neointimal rupture (OR: 3.640; 95% CI, 1.169-11.325, P = 0.026), red thrombus (OR: 4.482; 95% CI, 1.269-15.816, P = 0.020) and white thrombus (OR: 5.259; 95% CI, 1.660-16.659, P = 0.005). Patients with higher degrees of area stenosis in the context of ISR exhibited a greater number of discernible morphological characteristics as identified through OCT analysis. Furthermore, previous dyslipidemia, neointimal rupture, white thrombus and red thrombus were highly associated with and the progression of ISR lesions.