In Vivo Imaging of Rodent Retina in Retinal Disease.

High-quality imaging of the retina is crucial to the diagnosis and monitoring of disease, as well as for evaluating the success of therapeutics in human patients and in preclinical animal models. Here, we describe the basic principles and methods for in vivo retinal imaging in rodents, including fundus imaging, fluorescein angiography, optical coherence tomography, fundus autofluorescence, and infrared imaging. After providing a concise overview of each method and detailing the retinal diseases and conditions that can be visualized through them, we will proceed to discuss the advantages and disadvantages of each approach. These protocols will facilitate the acquisition of optimal images for subsequent quantification and analysis. Additionally, a brief explanation will be given regarding the potential results and the clinical significance of the detected abnormalities.

Long-term effect of biodegradable vs durable polymer everolimus-eluting stents on neoatherosclerosis in ST-segment elevation myocardial infarction: the CONNECT trial.

BACKGROUND AND AIMS: Neoatherosclerosis is a leading cause of late (>1 year) stent failure following drug-eluting stent implantation. The role of biodegradable (BP) versus durable polymer (DP) drug-eluting stents on long-term occurrence of neoatherosclerosis remains unclear. Superiority of biodegradable against durable polymer current generation thin-strut everolimus-eluting stent (EES) was tested by assessing the frequency of neoatherosclerosis 3 years after primary percutaneous coronary intervention (pPCI) among patients with ST-segment elevation myocardial infarction (STEMI). METHODS: The randomized controlled, multicentre (Japan and Switzerland) CONNECT trial (NCT03440801) randomly (1:1) assigned 239 STEMI patients to pPCI with BP-EES or DP-EES. The primary endpoint was the frequency of neoatherosclerosis assessed by optical coherence tomography (OCT) at 3 years. Neoatherosclerosis was defined as fibroatheroma or fibrocalcific plaque or macrophage accumulation within the neointima. RESULTS: Among 239 STEMI patients randomized, 236 received pPCI with stent implantation (119 BP-EES; 117 DP-EES). A total of 178 patients (75%; 88 in the BP-EES group and 90 in the DP-EES group) underwent OCT assessment at 3 years. Neoatherosclerosis did not differ between the BP-EES (11.4%) and DP-EES (13.3%; odds ratio 0.83, 95% confidence interval 0.33-2.04, p=0.69). There were no differences in the frequency of fibroatheroma (BP-EES 9.1% vs DP-EES 11.1%, p=0.66) or macrophage accumulation (BP-EES 4.5% vs DP-EES 3.3%, p=0.68), and no fibrocalcific neoatherosclerosis was observed. Rates of target lesion failure did not differ between groups (BP-EES 5.9% vs DP-EES 6.0%, p=0.97). CONCLUSIONS: Use of BP-EES for primary PCI in patients presenting with STEMI was not superior to DP-EES regarding frequency of neoatherosclerosis at 3 years.

Foveal avascular zone area measurement in diabetic patients: Superficial, deep or combined retinal vascular complex?

PURPOSE: To compare differences in the foveal avascular zone (FAZ) area, measured in the Superficial Vascular Complex (SVC), Deep Vascular Complex (DVC) and a combined analysis of both (SDVC), using two Spectral Domain OCT angiography (OCT-A) protocols, High Speed (HS) and High Resolution (HR). METHODS: A total of 26 eyes of diabetic patients, with and without macular oedema, were examined with two different fovea centered OCT-A volume scans. The two protocols were HS and HR volume scans, and the foveal avascular zone was manually measured in the SVC, DVC, and SDVC slabs by two masked investigators. Inter and intraoperator variability was analysed using Intraclass Correlation Coefficient (ICC) and differences were compared between the HR and HS acquisitions throughout the different vascular slabs. RESULTS: Intraoperator variability was low in all slabs (ICC > 0.9) and interoperator variability was lower for HR (ICC 0.835-0.911) compared to HS (ICC between 0.604 and 0.865). Comparing HS and HR measurements for the same slab, the correlation was only moderate in SVC and DVC (ICC was 0.640 and 0.568 respectively) but was good in the SDVC (ICC = 0.823). FAZ area measurement in SDVC also showed the smallest bias (mean difference 0.009 mm2) and the narrowest limits of agreement (-0.175 to 0.193 mm2). CONCLUSIONS: Even in cases of diabetic macular oedema, when measuring the FAZ area, the reproducibility was better between HS and HR protocols when using the SDVC slab, compared to the SVC or DVC slabs alone. Further studies should evaluate the use of the combined SDVC slab for the FAZ assessment, compared to the SVC and DVC slabs alone, in the detection and progression of different retinal diseases.

Emerging Hybrid Intracoronary Imaging Technologies and Their Applications in Clinical Practice and Research.

Intravascular ultrasound and optical coherence tomography are used with increasing frequency for the care of coronary patients and in research studies. These imaging tools can identify culprit lesions in acute coronary syndromes, assess coronary stenosis severity, guide percutaneous coronary intervention (PCI), and detect vulnerable plaques and patients. However, they have significant limitations that have stimulated the development of multimodality intracoronary imaging catheters, which provide improvements in assessing vessel wall pathology and guiding PCI. Prototypes combining 2 or even 3 imaging probes with complementary attributes have been developed, and several multimodality systems have already been used in patients, with near-infrared spectroscopy intravascular ultrasound-based studies showing promising results for the identification of high-risk plaques. Moreover, postmortem histology studies have documented that hybrid imaging catheters can enable more accurate characterization of plaque morphology than standalone imaging. This review describes the evolution in the field of hybrid intracoronary imaging; presents the available multimodality catheters; and discusses their potential role in PCI guidance, vulnerable plaque detection, and the assessment of endovascular devices and emerging pharmacotherapies targeting atherosclerosis.

Intravascular imaging-guided versus angiography-guided percutaneous coronary intervention: a systematic review and bayesian network meta-analysis of randomized controlled trials.

BACKGROUND: Percutaneous coronary intervention (PCI) has become one of the most commonly performed interventional life-saving procedures worldwide. Intravascular Imaging (intravascular ultrasound (IVUS) and optical coherence tomography (OCT)) have initially evolved to guide PCI compared with angiography. However, this technology is not universally employed in all PCI procedures, and there is ongoing controversy regarding its additional benefits to patient outcomes. We aim to estimate the efficacy and safety of imaging modalities during PCI, allowing pre-, per, and post-intervention assessment of coronary vascularization. METHODS: A systematic review and Bayesian network meta-analysis of randomized controlled trials (RCTs), which were retrieved from PubMed, WOS, SCOPUS, EMBASE, and CENTRAL through September 2023. We used R, version 4.2.0. Effect sizes will be presented as odds ratios with accompanying 95% credible intervals. PROSPERO ID: CRD42024507821. RESULTS: Our study, encompassing 36 RCTs with a total of 17,572 patients, revelead that compared to conventional angiography, IVUS significantly reduced the risk of major adverse cardiovascular events (MACE) (OR: 0.71 [95% CrI: 0.56 to 0.87]) but not OCT (OR: 0.91 [95% CrI: 0.62 to 1.39]), IVUS and OCT significantly reduced the risk of cardiac death (OR: 0.50 [95% CrI: 0.33 to 0.76]) and (OR: 0.55 [95% CrI: 0.31 to 0.98]), respectively, IVUS significantly reduced the risk of target vessel-related revascularization (OR: 0.60 [95% CrI: 0.48 to 0.75]) but not OCT (OR: 0.86 [95% CrI: 0.60 to 1.19]), IVUS and OCT significantly reduced the risk of stent thrombosis (OR: 0.50 [95% CrI: 0.28 to 0.92]) and (OR: 0.48 [95% CrI: 0.22 to 0.98]), respectively, IVUS significantly reduced the risk of re-stenosis (OR: 0.65 [95% CrI: 0.46 to 0.88]) but not OCT (OR: 0.55 [95% CrI: 0.15 to 1.99]), neither IVUS (OR: 0.97 [95% CrI: 0.71 to 1.38]) nor OCT (OR: 0.75 [95% CrI: 0.49 to 1.22]) were associated with statistically significant reductions in all-cause mortality, neither IVUS (OR: 0.70 [95% CrI: 0.45 to 1.32]) nor OCT (OR: 0.81 [95% CrI: 0.47 to 1.59]) were associated with statistically significant reductions in target vessel failure, neither IVUS (OR: 0.88 [95% CrI: 0.43 to 2.44]) nor OCT (OR: 0.81 [95% CrI: 0.37 to 2.04]) were associated with statistically significant reductions in target lesion failure, and neither IVUS (OR: 0.82 [95% CrI: 0.60 to 1.06]) nor OCT (OR: 0.84 [95% CrI: 0.59 to 1.19]) were associated with statistically significant reductions in myocardial infarction. CONCLUSION: Intravascular imaging-guided, including IVUS and OCT, improved the postinterventional outcomes of PCI, notably suggesting their advantage over traditional angiography with no significant difference between IVUS and OCT.

Macula Characteristics in Young Saudi Male Patients with Myopia: A Comparative Hospital-Based Study.

BACKGROUND: Myopia is associated with changes in the posterior segment of the eye, including the macula, which may contribute to potential blindness. Therefore, the study aims to evaluate the macula integrity in young myopic patients through optical coherence tomography (OCT). METHODS: A cross-sectional study was conducted at Qassim University optometry clinics from January to June 2024, involving 30 healthy young males with myopia and 30 with emmetropia. Clinical examination and OCT imaging were used to gather data on macular volume and thickness. The results were analyzed using descriptive statistics and correlation analysis. RESULTS: The study included 60 myopic eyes and 60 emmetropic eyes. The participants' mean age was 22.10 ± 1.65 years (p = 0.135). A significant difference was found between myopic and emmetropic eyes in fovea, parafovea, perifovea, and total macula thickness and volume (P < 0.05). Additionally, the study showed a significant positive correlation between the magnitude of myopia and fovea thickness (r = 0.297, p = 0.011) and negative correlations with perifovea thickness (r = -0.418, p < 0.001), total macula thickness (r = -0.353, p = 0.003), and total macula volume (r = -0.352, p = 0.003). However, parafoveal thickness had no significant correlation with the severity of myopia (r= -0.107; p=0.207). Fovea thickness was higher in high myopia (255.40 ± 23.51 µm) compared to low (238.69 ± 15.98 µm) and moderate (248.15 ± 8.70 µm) myopia. Perifovea thickness, macula thickness, and macula volume were significantly lower in high myopia (p ˃ 0.05). CONCLUSION: Myopia influences macular parameters compared to emmetropia. It increases fovea thickness and decreases total macula thickness and volume as well as perifovea thickness. High myopia has more alterations in macula parameters.

Noninvasive Technologies for the Diagnosis of Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis.

Early cutaneous squamous cell carcinoma (cSCC) diagnosis is essential to initiate adequate targeted treatment. Noninvasive diagnostic technologies could overcome the need of multiple biopsies and reduce tumor recurrence. To assess performance of noninvasive technologies for cSCC diagnostics, 947 relevant records were identified through a systematic literature search. Among the 15 selected studies within this systematic review, 7 were included in the meta-analysis, comprising of 1144 patients, 224 cSCC lesions, and 1729 clinical diagnoses. Overall, the sensitivity values are 92% (95% confidence interval [CI] = 86.6-96.4%) for high-frequency ultrasound, 75% (95% CI = 65.7-86.2%) for optical coherence tomography, and 63% (95% CI = 51.3-69.1%) for reflectance confocal microscopy. The overall specificity values are 88% (95% CI = 82.7-92.5%), 95% (95% CI = 92.7-97.3%), and 96% (95% CI = 94.8-97.4%), respectively. Physician's expertise is key for high diagnostic performance of investigated devices. This can be justified by the provision of additional tissue information, which requires physician interpretation, despite insufficient standardized diagnostic criteria. Furthermore, few deep learning studies were identified. Thus, integration of deep learning into the investigated devices is a potential investigating field in cSCC diagnosis.

Minocycline-induced retinal pigment epithelium hyperpigmentation masquerading as age-related macular degeneration: Case presentation and proposed mechanism.

Purpose: We describe the case of an 80-year-old man with bilateral minocycline-induced retinal pigment epithelium (RPE) hyperpigmentation, which initially masqueraded as AMD. Secondarily, using multimodal imaging features, we propose a mechanism for the development of minocycline-induced RPE hyperpigmentation. Observations: The patient was referred with concern for AMD given the presence of macular drusenoid deposits on optical coherence tomography. However, funduscopic evaluation showed dense granular parafoveal hyperpigmentation, with a diffuse slate-colored hyperpigmentation throughout the peripheral fundus. Short-wavelength fundus autofluorescence of the macula disclosed no irregularities (as would be expected with drusen) while on near-infrared reflectance (NIR) imaging, numerous hyperreflective foci were noted corresponding to the hyperpigmented granules observed clinically (as would instead be seen with melanin deposits). Clinical examination was notable for blue-gray hyperpigmentation of the lower and upper extremities, as well as of the face, periorbital skin, and sclera. Upon further questioning, the patient disclosed daily oral minocycline use for 15 years for acne rosacea, confirming a diagnosis of minocycline-induced hyperpigmentation of the RPE. Conclusions: Multimodal imaging can be useful for differentiating minocycline-induced RPE hyperpigmentation from similar masquerade entities. Timely diagnosis can prevent progressive vision loss.

Systemic immune inflammation index is associated with in-stent neoatherosclerosis and plaque vulnerability: An optical coherence tomography study.

Background: In-stent neoatherosclerosis (ISNA) is identified as the primary cause of in-stent restenosis (ISR). The systemic immune inflammation index (SII), shows promise for predicting post-percutaneous coronary intervention (PCI) adverse cardiovascular events and is associated with coronary stenosis severity; however, its specific relationship with ISNA remains unclear. This study aimed to investigate the association between the SII and ISNA after drug-eluting stent (DES) implantation. Methods: This cross-sectional study included 195 participants with 195 ISR lesions who underwent optical coherence tomography (OCT)-guided PCI between August 2018 and October 2022. Participants were categorized based on the SII levels into Tertile 1 (SII <432.37, n = 65), Tertile 2 (432.37 ≤ SII ≤751.94, n = 65), and Tertile 3 (SII >751.94, n = 65). Baseline Clinical, angiographic, and OCT characteristics were analyzed. The association of the SII with ISNA and thin-fibroatheroma (TCFA) was investigated using univariate and multivariate logistic regression analyses. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic accuracy of the SII in detecting ISNA and TCFA. Results: Patients in Tertile 3 had a significantly higher incidences of ISNA and TCFA than did those in Tertile 1. Logistic regression analysis revealed the SII is an independent indicator of ISNA and TCFA in ISR lesions (P = 0.045 and P = 0.002, respectively). The areas under the ROC curves for ISNA and TCFA were 0.611 and 0.671, respectively. Conclusion: The SII is associated with ISNA and TCFA and may serve as an independent indicator in patients with ISR.

Trends and Future Directions in Margin Analysis for Head and Neck Cancers.

Margin status in head and neck cancer has important prognostic implications. Currently, resection is based on manual palpation and gross visualization followed by intraoperative specimen or tumor bed-based margin analysis using frozen sections. While generally effective, this protocol has several limitations including margin sampling and close and positive margin re-localization. There is a lack of evidence on the association of use of frozen section analysis with improved survival in head and neck cancer. This article reviews novel technologies in head and neck margin analysis such as 3-dimensional scanning, augmented reality, molecular margins, optical imaging, spectroscopy, and artificial intelligence.

The assessment of structural and functional test results for early detection of hydroxychloroquine macular toxicity.

PURPOSE: To assess structural (optical coherence tomography, fundus autofluorescence) and functional (contrast sensitivity and visual field) test results which were used for detecting early retinal changes in patients using oral hydroxychloroquine. METHODS: Patients using oral hydroxychloroquine for at least one year were divided into two groups according to the duration of drug use. Groups 1 and 2 consisted of patients with drug use for more than 5 years and 1-5 years, respectively. The drug-using groups were compared with the control group. The mean retinal nerve fiber layer (RNFL), central macular thickness (CMT), ganglion cell-inner plexiform layer (GC-IPL), static 10-2 visual field, fundus autofluorescence (FAF) imaging, and contrast sensitivity tests were performed and statistically compared between groups. RESULTS: Median and temporal quadrant RNFL thicknesses were found to be statistically significantly lower in the drug groups. In the drug groups, the GC-IPL sectoral and mean thicknesses were found to be statistically lower in all quadrants. Central macular thickness was also found to be similar in all three groups. There was no significant difference between the groups in visual field parameters. Macular FAF images were significantly higher in the drug users, but there was no significant difference between the three groups in foveal FAF images. Contrast sensitivity measurements were significantly lower in the drug groups than in the control group at all spatial frequencies except 6 and 18 cycles/degree. CONCLUSIONS: The combined use of structural and functional tests in patients using hydroxychloroquine provides useful information in detecting early retinal changes.

Value of Combined Optical Coherence Tomography and Optical Flow Ratio Measurements after Percutaneous Coronary Intervention.

BACKGROUND: Optical flow ratio (OFR) is a novel computational fractional flow reserve derived from optical coherence tomography (OCT). However, the impact of combining post-stenting morphology (OCT) and physiology (OFR) remains largely unknown. METHOD: OCT and OFR were analyzed at the independent core laboratory. Target lesion failure (TLF) was defined as the composite of cardiac death, target lesion myocardial infarction and target lesion revascularization. Suboptimal stent deployment was identified with at least one TLF-related OCT or OFR characteristics. RESULTS: A total of 448 ACS patients (459 vessels) were assessed. Stent expansion<80%, MSA<4.5 mm2 and stent edge lipid-rich plaque and OFR<0.90 were independent predictors of TLR (all p value<0.001). Patients with OCT-suboptimal [adjusted hazard ratio (HR): 7.88, 95% CI: 2.73-22.72, p<0.001] or OFR-suboptimal (adjusted HR: 5.78, 95% CI: 2.54-13.14, p<0.001) stent deployment showed significantly higher risk of TLF compared to those with optimal stent deployment with a significant interaction (pinteraction<0.001). OCT and OFR both-suboptimal stent deployment was confirmed as an independent predictor of TLF (adjusted HR: 9.39, 95% CI: 4.25-20.76, p<0.001). CONCLUSION: Combined OCT and OFR conferred an optimal reclassification of stent deployment, which may aid in decision-making regarding a tailored PCI strategy for optimal stent deployment.

NIRS-IVUS Assessment of OCT-Derived Healed Coronary Plaques.

AIMS: Healed plaque (HP) is associated with rapid plaque growth and luminal narrowing. Thin-cap fibroatheroma (TCFA) is recognized as a precursor lesion to plaque rupture. The aim of the present study was to compare the lipid size among optical coherence tomography (OCT)-derived HP, TCFA, and thick-cap fibroatheroma (ThCFA) using near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS). METHODS: The present study included 173 patients with acute myocardial infarction (AMI) who underwent percutaneous coronary intervention. Non-culprit lesions with angiographically intermediate stenosis were assessed by both OCT and NIRS-IVUS. RESULTS: The frequency of TCFA, HP, and ThCFA was 35 (20%), 53 (30%), and 85 (49%), respectively. Minimum lumen area was not significantly different between TCFA and HP, but was smaller in TCFA and HP than in ThCFA (4.6 [interquartile range {IQR}: 3.5-6.4] mm2 vs. 4.3 [3.4-5.3] mm2 vs. 6.5 [4.8-8.6] mm2, P＜0.001). Plaque burden was not significantly different between TCFA and HP, but was larger in TCFA and HP than in ThCFA (72 [IQR: 66-80] % vs. 75 [67-80] % vs. 62 [54-69] %, P＜0.001). Maximum lipid core burden index in 4mm (maxLCBI4mm) was largest in TCFA, followed by HP and ThCFA (493 [IQR: 443-606] vs. 446 [347-520] vs. 231 [161-302], P＜0.001). The frequency of lipid rich plaque with maxLCBI4mm ＞400 was highest in TCFA, followed by HP and ThCFA (89% vs. 60% vs. 7%, P＜0.001). CONCLUSIONS: Based on NIRS-IVUS findings, non-culprit coronary HP in AMI was associated with vulnerable plaque characteristics, but not as much as TCFA.

Sea-fan retinal neovascularization associated with rickettsial retinitis: a case report.

BACKGROUND: Rickettsial disease has been commonly associated with retinitis, retinal vasculitis, and optic nerve involvement, but the development of retinal neovascularization has been very rarely reported. We herein describe a case of rickettsial retinitis complicated with the development of sea-fan retinal neovascularization documented with multimodal imaging, including fundus photography, SS-OCT, fluorescein angiography, and SS-OCT angiography. CASE PRESENTATION: A 26-year-old female with a history of fever one week earlier presented with sudden decreased vision in the left eye. Best-corrected visual acuity (BCVA) was 20/2000 and the patient was diagnosed with rickettsial retinitis along the superotemporal retinal vascular arcade associated with serous retinal detachment and retinal hard exudates. The indirect immunofluorescence test was positive for Rickettsia conorii, and the patient was treated with oral doxycycline (200 mg/day) and oral prednisone (0.75 mg/kg/day, with gradual tapering). Four weeks after presentation, the retinal infiltrate and associated serous retinal detachment had resolved, but retinal hard exudates had increased. A large sea-fan preretinal fibrovascular neovascularization became apparent along the superotemporal retinal vascular arcade, but there was no associated retinal ischemia on fluorescein angiography. The patient received an adjunctive single intravitreal injection of 1.25 bevacizumab. Sequential follow-up examinations showed shrinking of sea-fan retinal neovascularization, a complete resolution of retinal hard exudates, and the development of a self-limited vitreous hemorrhage. On last follow-up, 30 months after intravitreal bevacizumab injection, BCVA was 20/25. CONCLUSION: Patients with rickettsial retinitis may develop a sea-fan retinal neovascularization, with subsequent vitreous hemorrhage, putatively through inflammatory mechanisms. Multimodal imaging including OCT, fluorescein angiography, and OCT-angiography, is highly useful for accurate diagnosis and reliable monitoring of the evolution of retinitis, retinal neovascularization, and other retinal changes. The use of a combination therapy with oral doxycycline and corticosteroids and intravitreal anti-VEGF can improve outcomes.

Comparison of facial skin ageing in healthy Asian and Caucasian females quantified by in vivo line-field confocal optical coherence tomography 3D imaging.

BACKGROUND: Quantitative biomarkers of facial skin aging were investigated in 109 healthy Asian female volunteers, aged 20 to 70 years. MATERIALS AND METHODS: In vivo 3D Line-field Confocal Optical Coherence Tomography (LC-OCT) imaging, enhanced by Artificial Intelligence (AI)-based quantification algorithms, was utilized to compute various metrics, including stratum corneum thickness (SC), viable epidermal (VE) thickness, and Dermal-Epidermal Junction (DEJ) undulation along with cellular metrics for the temple, cheekbone, and mandible. RESULTS: Comparison with data from a cohort of healthy Caucasian volunteers revealed similarities in the variations of stratum corneum and viable epidermis layers, as well as cellular shape and size with age in both ethnic groups. However, specific findings emerged, such as larger, more heterogeneous nuclei in both layers, demonstrated by an increase in nuclei volume and their standard deviation, and increased network atypia, all showing significant age-related variations. Caucasian females exhibited a flatter and more homogeneous epidermis, evidenced by a decreased standard deviation of the number of layers, and a less dense cellular network with fewer cells per layer, indicated by a decrease in cell surface density. CONCLUSION: Ethnicity-wise comparisons highlighted distinct biological features specific to each population. Asian individuals showed significantly higher DEJ undulation, higher compactness, and lower cell network atypia compared to their Caucasian counterparts across age groups. Differences in stratum corneum and viable epidermal thickness on the cheekbone were also significant. LC-OCT 3D imaging provides valuable insights into the aging process in different populations and underscores inherent biological differences between Caucasian and Asian female volunteers.

Differential culprit plaque morphology in acute coronary syndrome: a comparison between very young patients (≤35 years) and older counterparts using optical coherence tomography.

Aims: Underlying mechanisms responsible for acute coronary syndrome (ACS) in young patients compared with older counterparts are yet to be explored with optical coherence tomography (OCT). This study aims to explore underlying mechanisms of ACS in ≤35- (very young) and >35-year-old (older counterparts) ACS patients using OCT. Methods and results: This was a prospective, single-centre, investigational study. Patients were divided into groups according to age (≤35 and >35 years) and further subdivided according to the underlying mechanism i.e. plaque rupture (PR) and plaque erosion (PE). A total of 93 patients were analysed. Thin-cap fibroatheroma (TCFA) was significantly higher among older counterparts than very young patients for both PR (80.0% vs. 31.8%, P = 0.002) and PE (66.7% vs. 6.3%, P < 0.001) groups. Microchannels were also significantly more prevalent among older than very young patients for both PR (65.0% vs. 18.2%, P = 0.004) and PE groups (55.6% vs.12.5%, P = 0.013). Macrophages were significantly higher in older than very young patients for both PR (25.0% vs. 0%, P = 0.018) and PE (44.4% vs. 0%, P = 0.003) groups. In contrast, fibrous cap thickness was greater in very young than older patients for both PR (105.71 ± 48.02 vs. 58.00 ± 15.76 µm, P < 0.001) and PE (126.67 ± 48.22 vs. 54.38 ± 24.21 µm, P < 0.001) groups. Intimal thickness was greater in older than very young patients for both PR (728.00 ± 313.92 vs. 342.27 ± 142.02 µm, P < 0.001) and PE (672.78 ± 334.57 vs. 295.00 ± 99.60 µm, P < 0.001) groups. Conclusion: Frequency of TCFA, microchannels, macrophages, and intimal thickness was significantly higher in older ACS patients compared with very young patients. However, fibrous cap thickness was significantly greater in very young ACS patients compared with older patients.

Application of the full-width-at-half-maximum image segmentation method to analyse retinal vascular changes in patients with internal carotid artery stenosis.

Background: To investigate the correlation between retinal vascular changes and ICA stenosis by measuring retinal vessels using full-width-at-half-maximum (FWHM) and intelligent image recognition. Methods: This research selected patients who were admitted to the Vascular Surgery Department of Quzhou People's Hospital from January 2018 to December 2020 and were preparing for Carotid Artery Stenting (CAS). Participants were divided into two groups: without ICA stenosis (Group 0) and with ICA stenosis (Group 1). A total of 109 cases were included in the study, with 50 cases in Group 1 and 59 cases in Group 0. Vascular images of superior temporal zone B of the retina were obtained by spectral domain optical coherence tomography (SD-OCT). The edges of retinal vessels were identified by FWHM. Each vessel of all subjects was measured three times with the FWHM, and the average value was taken to obtain the retinal arteriolar lumen diameter (RALD), retinal arteriolar outer diameter (RAOD), retinal venular lumen diameter (RVLD), and retinal venular outer diameter (RVOD),Arterial Wall Thickness (AWT),Venular Wall Thickness (VWT)=(RVOD-RVLD)/2,Arteriovenous Ratio (AVR) = RAOD/RVOD. Results: We found that compared to Group 0, Group 1 had smaller RALD (P < 0.001) and RAOD (P < 0.001), and wider RVOD (P < 0.001), with thicker VWT (P < 0.001). When compared with the contralateral eye in Group 1, the ipsilateral eye exhibited even smaller RALD,RAOD and AVR (P < 0.001, P < 0.001, P < 0.001). After CAS, the RALD,RAOD and AVR in Group 1 increased (P < 0.001, P < 0.001, P < 0.001),while the RVLD and RVOD decreased (P < 0.05, P < 0.001). Our research reveals a significant correlation between retinal vascular changes and internal ICA stenosis. Conclusion: Utilizing SD-OCT in conjunction with the FWHM,we achieved a non-invasive, intelligent, stable, and precise acquisition of data pertaining to retinal vessels. These findings underscore a significant correlation between alterations in retinal vascular structure and the presence of ICA stenosis, as demonstrated by our research.

Subretinal Exudation: The First Presentation of Untreated Choroidal Melanomas.

Introduction: This case series aims to present the unusual clinical manifestation of subretinal exudation in patients diagnosed with untreated choroidal melanoma. A total of 886 patients were diagnosed and treated for primary choroidal melanoma between November 2017 and June 2023 at St. Paul's Eye Unit, Royal Liverpool University Hospital, UK. The fundus photographs were screened for lipid exudates by two independent clinical experts. The patients' demographics, clinical manifestations, and imaging features were analysed, whereas the location of exudation was documented with fundus photographs and optical coherence tomography (OCT). The histopathological and genetic results were also analysed in cases with tumour biopsy available. Case Presentations: Eight cases with subretinal exudates were identified (n = 8/886, 0.90%). No gender predilection was noticed (male/female 1:1), whereas the mean age was 51 years (range 39-79). Four patients were asymptomatic at presentation, 2 patients reported reduced visual acuity, and 2 patients presented with photopsia. OCT scans revealed the presence of subretinal fluid and subretinal exudates, while the ultrasound showed medium or low internal reflectivity in 7 out of 8 cases. The biopsy analysis was available in 4 cases, all showing low-risk spindle cell choroidal melanoma with disomy 3. Conclusion: Lipid exudates are an atypical fundoscopic finding in patients with untreated choroidal melanoma. The subretinal location could differentiate them from other retinal vascular conditions and facilitate early diagnosis and intervention. Interestingly, all cases tested cytogenetically were of low metastatic risk; these exudates may, therefore, be a positive clinical prognostic sign.

Quantifying Changes on OCT in Eyes Receiving Treatment for Neovascular Age-Related Macular Degeneration.

Purpose: Application of artificial intelligence (AI) to macular OCT scans to segment and quantify volumetric change in anatomical and pathological features during intravitreal treatment for neovascular age-related macular degeneration (AMD). Design: Retrospective analysis of OCT images from the Moorfields Eye Hospital AMD Database. Participants: A total of 2115 eyes from 1801 patients starting anti-VEGF treatment between June 1, 2012, and June 30, 2017. Methods: The Moorfields Eye Hospital neovascular AMD database was queried for first and second eyes receiving anti-VEGF treatment and had an OCT scan at baseline and 12 months. Follow-up scans were input into the AI system and volumes of OCT variables were studied at different time points and compared with baseline volume groups. Cross-sectional comparisons between time points were conducted using Mann-Whitney U test. Main Outcome Measures: Volume outputs of the following variables were studied: intraretinal fluid, subretinal fluid, pigment epithelial detachment (PED), subretinal hyperreflective material (SHRM), hyperreflective foci, neurosensory retina, and retinal pigment epithelium. Results: Mean volumes of analyzed features decreased significantly from baseline to both 4 and 12 months, in both first-treated and second-treated eyes. Pathological features that reflect exudation, including pure fluid components (intraretinal fluid and subretinal fluid) and those with fluid and fibrovascular tissue (PED and SHRM), displayed similar responses to treatment over 12 months. Mean PED and SHRM volumes showed less pronounced but also substantial decreases over the first 2 months, reaching a plateau postloading phase, and minimal change to 12 months. Both neurosensory retina and retinal pigment epithelium volumes showed gradual reductions over time, and were not as substantial as exudative features. Conclusions: We report the results of a quantitative analysis of change in retinal segmented features over time, enabled by an AI segmentation system. Cross-sectional analysis at multiple time points demonstrated significant associations between baseline OCT-derived segmented features and the volume of biomarkers at follow-up. Demonstrating how certain OCT biomarkers progress with treatment and the impact of pretreatment retinal morphology on different structural volumes may provide novel insights into disease mechanisms and aid the personalization of care. Data will be made public for future studies. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.