Changes In Caliber Research Articles

Differences in the Microvascular Arrangement Lead to Improved Clinical Diagnostics of Esophageal Neoplasms: A Single-Center Retrospective Study

Background/Objectives: Superficial esophageal cancer is diagnosed by evaluating the vascular architecture, including dilation, tortuosity, caliber change, and shape, of a lesion. However, this diagnosis is subjective and requires extensive experience. Endoscopically distinguishing squamous intraepithelial neoplasia (SIN) from esophageal cancer is difficult. Thus far, only a few studies have described the endoscopic findings of SIN. Therefore, the present study aimed to investigate whether endoscopic observation of the vascular architecture of tumors is useful in differentiating SIN from superficial esophageal cancer (SCC). Methods: This study included 141 patients who were histopathologically diagnosed with SIN or SCC between 2007 and 2023. Based on endoscopic images, patients were divided into those with a regular vascular arrangement (regular group) and those with an irregular vascular arrangement (irregular group). After evaluating the clinical characteristics, propensity score matching was used to assess the association between the groups and their pathological diagnoses. Results: Of the 141 patients, 44 and 97 were in the regular and irregular groups, respectively, with a ratio of 1:2. After propensity score matching, 33 and 66 patients were included in the regular and irregular groups, respectively. There were no significant differences between the groups after matching for age, alcohol consumption, smoking status, lesion site, sex, or lesion size. The regular group had significantly more patients with SIN, whereas the irregular group had significantly more patients with esophageal cancer (p < 0.001). Conclusions: The regularity of the vascular architecture may be useful for endoscopically distinguishing between SIN and esophageal cancer.

Role of scalp arteries in revascularization after side to side anastomosis in moyamoya disease patients

In our recent study, we introduced a novel side-to-side (S-S) bypass technique for adult moyamoya disease (MMD) patients. We aimed to validate the potential of this technique in enhancing postoperative revascularization. Patients undergoing S-S or end-to-side (E-S) bypass were enrolled, clinical data and angiography parameters were collected and compared. We included 44 E-S and 40 S-S MMD patients. There were no significant differences in basic characteristics and postoperative Matsushima grades between the two groups. However, in the S-S group, fewer patients had Matsushima grade D (0%) compared to the E-S group (11.4%, P = 0.028). The S-S group showed a greater occipital artery (OA) participation in revascularization (87.5% vs. 56.8%, P = 0.002) and higher postoperative caliber change ratio (CCR) of the superficial temporal artery (STA)-frontal branch (1.26 ± 0.43 vs. 1.04 ± 0.53, P = 0.038) compared to the E-S group. This difference was more pronounced in the subgroup with poor revascularization outcomes: in the S-S group, the CCR of the STA-frontal branch and the degree of participation in revascularization were 1.163 ± 0.168 and 58.8%, respectively, while in the E-S group, they were only 0.798 ± 0.494 and 6.7%. The S-S group also had a higher OA CCR (1.133 ± 0.257) and participation (82.4%) compared to the E-S group (0.941 ± 0.216 and 37.5%, respectively). In conclusion, the S-S bypass technique effectively utilizes scalp arteries, particularly the STA-frontal branch and OA, for direct revascularization via the preserved distal STA in adult MMD patients. Scalp arteries can serve as a supplementary source of donor arteries, especially beneficial for patients with suboptimal revascularization outcomes.

Exploring the Relation Between Peripapillary Retinal Vessel Caliber and Visual Field Defects in Primary Open-Angle Glaucoma.

Background Primary open-angle glaucoma (POAG) is a progressive optic neuropathy characterized by loss of retinal ganglion cells, optic nerve head changes, and visual field defects. Vascular factors, alongside intraocular pressure, play a crucial role in POAG pathogenesis, and this study aims to explore the relationship between retinal vessel caliber and visual field defects in POAG patients. Purpose To evaluate the association between retinal vessel calibers in the peripapillary area with visual field defects in one or both hemifields. Materials and Methods This cross-sectional study was conducted at a tertiary eye care center in northern Karnataka for one year, enrolling 100 eyes from 50 primary open-angle glaucoma (POAG) patients with visual field abnormalities. Fundus color stereoscopic photographs were taken using a Canon digital camera, and diameters of the superior and inferior temporal arteries (STA and ITA) and veins (STV and ITV) in the peripapillary area were measured. Visual field defects were categorized, and statistical analyses were performed to correlate retinal vessel calibers with field defect locations. Results Participants had a mean age of 89.68 years, with 72% male. Visual field defects included superior arcuate scotoma (20%), inferior arcuate scotoma (32%), double arcuate scotoma (30%), and tubular vision (18%). Significant vessel caliber changes were observed: for superior hemifield defects, the mean STA: ITA ratio was 1.15 (p = 0.001), and for inferior defects, it was 0.94 (p = 0.04). STV: ITV ratios also showed significant changes corresponding to visual field defects. Eyes with defects in both hemifields showed pronounced narrowing, particularly in inferotemporal vessels. Conclusions Decreased retinal vessel caliber is significantly associated with visual field defects in primary open-angle glaucoma and can be a valuable diagnostic parameter tool for assessing glaucomatous damage and the progression and severity of POAG.

Development of a Precipitation Climate Record from Spaceborne Precipitation Radar Data. Part II: Temporal Adjustment of the Calibration Change Using the Ocean Normalized Radar Cross Section

Abstract We analyze the calibration stability of the 17-yr precipitation radar (PR) data on board the Tropical Rainfall Measuring Mission (TRMM) satellite to develop a precipitation climate record from the spaceborne precipitation radar data of the TRMM and following satellite missions. Since the PR measures the normalized radar cross section (NRCS) over the ocean surface, the temporal change in the NRCS whose variability is insensitive to the sea surface wind is regarded as the temporal change of the PR calibration. The temporal change of the PR calibration in TRMM, version 7, is found to be 0.19 dB decade−1 from 1998 to 2013. The calibration change is simply adjusted to evaluate the NRCS time series and the near-surface precipitation trend analysis within the latitudinal band between 35°S and 35°N. The NRCS time series at nadir and off-nadir are uncorrelated before the calibration adjustment, but they are correlated after the adjustment. The 0.19 dB decade−1 change of the PR calibration causes an overestimation of 0.08 mm day−1 decade−1 or 2.9% decade−1 for the linear trend of the near-surface precipitation. Even after the adjustment, agreement of the results among the satellite products depends on the analysis period. The temporal stability of the data quality is also important to evaluate the plausible trend analysis. The reprocessing of the PR data in TRMM, version 8 (or later), takes into account the temporal adjustment of the calibration change based upon the results of this study, which can provide more credible data for a long-term precipitation analysis. Significance Statement The stability of long-term data is very important for climate research so that an account of temporal calibration changes in the sensor must be made. In this study, we investigate the calibration stability of the TRMM PR data and evaluate its impact on the precipitation trend analysis. The temporal change of the PR calibration is estimated to be 0.19 dB decade−1. Compensating for this change improves the consistency of precipitation trend analysis between the PR and other precipitation datasets. The reprocessed PR data provide more probable data for long-term precipitation analysis.

The Optical Nature of Myopic Changes in Retinal Vessel Caliber

PurposeDimensional measures of retinal features are subject to the optical influence of ocular magnification. We examined the impact of ocular magnification on the association between axial length (AL) and measurements of retinal vessel calibre in fundus photographs. DesignCross-sectional study. ParticipantsEighty-two normal right eyes from healthy participants aged 16-31 years. MethodsCentral retinal arteriolar and venular equivalents (CRAE and CRVE) were derived from colour fundus photographs using semi-automated software. Ordinary least squares linear regression was used to assess the influence of AL (independent variable) on CRAE and CRVE, controlling for age, sex and ethnicity, both before and after magnification correction using different formulae. These formulae estimate magnification based on different ocular parameters: AL only (Bennnett’s formula), refractive error only (Bengtsson’s formula) and refractive error combined with keratometry (Littmann’s formula). Previous research has primarily relied on Bengtsson’s formula, which is less accurate than Bennett’s formula. We also examined the impact of treating the non-telecentric fundus camera used in this study as telecentric when applying these magnification correction formulae. Main Outcome MeasuresCentral retinal arteriolar and venular equivalents (in pixels). ResultsBefore magnification correction, increasing AL was associated with decreasing CRAE (β: -0.49, 95% CI: -0.89 to -0.09, p=0.02) and CRVE (β: -0.91, 95% CI: -1.62 to -0.20, p=0.01). After magnification correction, this observation was no longer evident, regardless of the correction formula applied. When inappropriately assuming the fundus camera to be telecentric, we observed a bias towards increasing magnification-corrected CRAE and CRVE with increasing AL (β coefficients were positive or became more positive), reaching statistical significance (p<0.05) for CRAE corrected using Bennett’s or Littmann’s formula, and for CRVE corrected using Bennett’s formula. ConclusionsFailing to correct for ocular magnification results in apparent narrowing of vessels in longer eyes, while inappropriate assumptions about telecentricity during magnification correction introduce an optical artifact that causes apparent widening of vessels. These findings suggest that myopic changes in retinal vessel calibre are optical (not biological) in nature. Proper correction of this effect to accurately derive dimensional measures is a crucial—yet often overlooked—methodological consideration in “oculomics” research investigating retinal biomarkers of systemic conditions.

ECG–gated retinal vessel calibre as a novel measure of aberrant pulsatile retinal flow in diabetes mellitus: a cross-sectional study

PurposeTo evaluate ECG-gated retinal vessel calibre as a novel measure of aberrant pulsatile retinal flow in diabetes mellitus.MethodsA novel mydriatic ECG-gated fundoscope was used to acquire retinal vessel calibre measurements at four cardiac cycle time points from end diastole to early diastole. An inhouse software recorded the exact time when an image was captured to corroborate ECG-synchronisation. Arterial applanation tonometry, an alternative method of assessing aberrant blood flow, was used to measure carotid-femoral pulse wave velocity (cPWV) and augmentation index (AIx). The intraclass correlation (ICC) was used to perform intra- and inter-observer reliability analyses. Two reviewers measured the retinal vessel calibre in single retinal arterioles and venules. A receiver operating characteristic curve determined associations with diabetes mellitus.ResultsIn this study 119 controls and 120 participants with diabetes mellitus were recruited. Mean peak change in retinal arteriolar calibre from baseline was higher in diabetes mellitus compared with controls (controls: 0.92%, IQR 0.63 vs diabetes mellitus: 2.05%, IQR 1.25, p<0.0001). In a subset of 9 controls and 11 participants, the intra-and inter-observer reliability was high (ICC 0.87-0.97) in mean peak changes in retinal vascular responses from baseline. In a subset of 36 controls and 95 participants with diabetes mellitus, diabetes mellitus was more strongly associated with retinal arteriolar pulsatility (AUC 0.85, 95%CI 0.76-0.93) than applanation tonometry (cfPWV AUC 0.72, 95%CI 0.62-0.82 vs AIx AUC 0.56, 95%CI 0.45-0.68).ConclusionHigher retinal arteriolar pulsatility appears to be more strongly correlated with diabetes mellitus than arterial applanation tonometry.

Decade‐Long Ozone Profile Record From Suomi NPP OMPS Limb Profiler: Assessment of Version 2.6 Data

AbstractWe evaluate a decadal ozone profile record derived from the Suomi National Polar‐orbiting Partnership (SNPP) Ozone Mapping and Profiler Suite (OMPS) Limb Profiler (LP) satellite instrument. In 2023, the OMPS LP data were re‐processed with the new version 2.6 retrieval algorithm that combines measurements from the ultraviolet (UV) and visible (VIS) parts of the spectra. It employs the second order Tikhonov regularization to retrieve a single vertical ozone profile between 12.5 km (or cloud tops) and 57.5 km with a vertical resolution of about 1.9–2.5 km between 20 and 55 km. The algorithm uses radiances measured at six UV ozone‐sensitive wavelengths (295, 302, 306, 312, 317, and 322 nm) paired with 353 nm, and one VIS wavelength at 606 nm combined with 510 and 675 nm to form a triplet. Each wavelength pair or triplet is used over a limited range of tangent altitudes where the sensitivity to ozone change is strongest. A new aerosol correction scheme was implemented based on a gamma‐function particle size distribution. In addition, numerous calibration changes that affected ozone retrievals were applied to measured LP radiances, including updates in altitude registration, radiometric calibration, stray light, and spectral registration. The key version 2.6 enhancement is the improved stability of the LP ozone record confirmed by the reduction in relative drifts between LP ozone and correlative measurements, linked previously to a drift in the version 2.5 LP altitude registration.

Long-term enlargement of the neo-aortic root and aortic arch following arch reconstruction in hypoplastic left heart syndrome

BackgroundLong-term enlargement of the aortic arch after aortic arch reconstruction in hypoplastic left heart syndrome is not well described. MethodsAortic arch measurements for 50 patients with hypoplastic left heart syndrome who achieved Fontan completion were converted to Pediatric Heart Network z-scores. Dimensions were assessed using linear mixed models, and differences among time points were evaluated with F-tests. Sub-analysis was conducted comparing Norwood (n = 36) with hybrid (n = 14) strategies. ResultsMedian time to last imaging was 6.4 (interquartile range, 3.5-11.3) years. Before intervention, the main pulmonary artery was dilated, whereas the ascending aorta, transverse arch, and isthmus were hypoplastic. With aortic arch reconstruction, there were expected increases in all arch z-scores. The aortic arch continued to dilate after aortic arch reconstruction, reaching peak values at 7 months (neo-aortic complex: z = 6.9 [5.6-8.0]) or 12 months after stage I (ascending aorta: z = 6.1 [2.9-8.3]; transverse arch: z = 4.7 [3.0-5.9]). After peak values, there was a gradual decline in z-scores with most components still at least mildly dilated at 16 years (neo-aortic complex: z = 3.2 [3.1-3.9], ascending aorta: z = 3.9 [3.3-4.2]; transverse arch: z = 3.1 [2.5-3.7]) with abrupt caliber change at the isthmus: z = −0.8 (−1.1 to −0.3). Norwood and hybrid strategies showed similar enlargement profiles after 7 months of age. ConclusionsNeo-aortic root and aortic arch in hypoplastic left heart syndrome are enlarged early after aortic arch reconstruction and continue to enlarge out of proportion to normal controls until 12 months of age, with gradual decline in enlargement up to adolescence. Further work should focus on modifiable surgical factors that may prove important to optimize arch growth and geometry.

New limit on dark photon kinetic mixing in the 0.2–1.2 μeV mass range from the Dark E-field Radio experiment

We report new limits on the kinetic mixing strength of the dark photon spanning the mass range 0.21−1.24 μeV corresponding to a frequency span of 50–300 MHz. The Dark E-field Radio experiment is a wideband search for dark photon dark matter. In this paper we detail changes in calibration and upgrades since our proof-of-concept pilot run. Our detector employs a wide-bandwidth E-field antenna moved to multiple positions in a shielded room, a low noise amplifier, wideband analog-to-digital converter, followed by a 224-point fast Fourier transform. An optimal filter searches for signals with Q≈106. In nine days of integration, this system is capable of detecting dark photon signals corresponding to a kinetic mixing strength ε several orders of magnitude lower than previous limits. We find a 95% exclusion limit on ε over this mass range between 6×10−15 and 6×10−13, tracking the complex resonant mode structure in the shielded room. Published by the American Physical Society 2024

An imaging-based model to predict the malignant potential of intraductal papillary mucinous neoplasm of the pancreas.

To develop and validate imaging-based models for predicting the malignancy risk of intraductal papillary mucinous neoplasm (IPMN). We retrospectively analyzed data from 241 IPMN patients who underwent preoperative CT and MRI for model development. Cyst size, presence and size of the enhancing mural nodule (EMN), main pancreatic duct (MPD) diameter, thickened/enhancing cyst wall, abrupt MPD caliber change with distal atrophy, and lymphadenopathy were assessed. Multiple logistic regression models predicting malignancy risk were created using either continuous (Model C) or dichotomized variables (Model D) using these imaging features. Validation included internal (n = 55) and external (n = 43) datasets. Model performance was assessed using the area under the receiver operating characteristic curve (AUC) and compared with that of the international guideline-based model (Model F). Model C identified age, EMN size, MPD diameter, and lymphadenopathy as independent predictors on CT, and age and presence and size of EMN on MRI. Model D identified age ≥ 68, cyst size ≥ 31 mm, EMN ≥ 6 mm, MPD ≥ 7 mm, and lymphadenopathy as independent predictors on CT, and age ≥ 68, EMN ≥ 4.5 mm, and lymphadenopathy on MRI. Model C (AUC, 0.763-0.899) performed slightly better than Model D (AUC, 0.753-0.912) without statistical significance. No significant difference was observed between Models C and F (AUC, 0.729-0.952). Combining Model C with obstructive jaundice improved performance (AUC, 0.802-0.941) without statistical significance. Our imaging-based models effectively predicted the malignancy risk of IPMNs, comparable to international consensus guidelines. Imaging features are important for predicting the malignant potential of IPMNs. Our imaging-based model may help determine surgical candidacy for patients with IPMNs. Non-invasively determining the malignant potential of intraductal papillary mucinous neoplasms (IPMNs) allows for appropriate treatment decision-making We identified multiple imaging features that are associated with malignant transformation and developed models for this prediction. Our model performs comparably with international consensus guidelines in predicting the malignant potential of IPMNs.

Colorimetric Analyses of the Optic Nerve Head and Retina Indicate Increased Blood Flow After Vitrectomy.

The purpose of this study was to evaluate the impact of vitrectomy and posterior hyaloid (PH) peeling on color alteration of optic nerve head (ONH) and retina as a surrogate biomarker of induced perfusion changes. Masked morphometric and colorimetric analyses were conducted on preoperative (<1month) and postoperative (<18months) color fundus photographs of 54 patients undergoing vitrectomy, either with (44) or without (10) PH peeling and 31 years of age and gender-matched control eyes. Images were calibrated according to the hue and saturation values of the parapapillary venous blood column. Chromatic spectra of the retinal pigment epithelium and choroid were subtracted to avoid color aberrations. Red, green, and blue (RGB) bit values over the ONH and retina were plotted within the constructed RGB color space to analyze vitrectomy-induced color shift. Vitrectomy-induced parapapillary vein caliber changes were also computed morphometrically. A significant post-vitrectomy red hue shift was noted on the ONH (37.1degrees ± 10.9degrees vs. 4.1degrees ± 17.7degrees, P < 0.001), which indicates a 2.8-fold increase in blood perfusion compared to control (2.6 ± 1.9 vs. 0.9 ± 1.8, P < 0.001). A significant post-vitrectomy increase in the retinal vein diameter was also noticed (6.8 ± 6.4% vs. 0.1 ± 0.3%, P < 0.001), which was more pronounced with PH peeling (7.9 ± 6.6% vs. 3.1 ± 4.2%, P = 0.002). Vitrectomy and PH peeling increase ONH and retinal blood flow. Colorimetric and morphometric analyses offer valuable insights for future artificial intelligence and deep learning applications in this field. The methodology described herein can easily be applied in different clinical settings and may enlighten the beneficial effects of vitrectomy in several retinal vascular diseases.

Comparative study on the quality control effectiveness of AI-PBRTQC and traditional PBRTQC model in identifying quality risks.

We compared the quality control efficiency of artificial intelligence-patient-based real-time quality control (AI-PBRTQC) and traditional PBRTQC in laboratories to create favorable conditions for the broader application of PBRTQC in clinical laboratories. In the present study, the data of patients with total thyroxine (TT4), anti-Müllerian hormone (AMH), alanine aminotransferase (ALT), total cholesterol (TC), urea, and albumin (ALB) over five months were categorized into two groups: AI-PBRTQC group and traditional PBRTQC group. The Box-Cox transformation method estimated truncation ranges in the conventional PBRTQC group. In contrast, in the AI-PBRTQC group, the PBRTQC software platform intelligently selected the truncation ranges. We developed various validation models by incorporating different weighting factors, denoted as λ. Error detection, false positive rate, false negative rate, average number of the patient sample until error detection, and area under the curve were employed to evaluate the optimal PBRTQC model in this study. This study provides evidence of the effectiveness of AI-PBRTQC in identifying quality risks by analyzing quality risk cases. The optimal parameter setting scheme for PBRTQC is TT4 (78-186), λ = 0.03; AMH (0.02-2.96), λ = 0.02; ALT (10-25), λ = 0.02; TC (2.84-5.87), λ = 0.02; urea (3.5-6.6), λ = 0.02; ALB (43-52), λ = 0.05. The AI-PBRTQC group was more efficient in identifying quality risks than the conventional PBRTQC. AI-PBRTQC can also effectively identify quality risks in a small number of samples. AI-PBRTQC can be used to determine quality risks in both biochemistry and immunology analytes. AI-PBRTQC identifies quality risks such as reagent calibration, onboard time, and brand changes.

Dynamic internal jugular vein venography: a descriptive study in 89 patients with suspected cerebral venous outflow disorders

BackgroundInternal jugular vein (IJV) stenosis has recently been recognized as a plausible source of symptom etiology in patients with cerebral venous outflow disorders (CVD). Diagnosis and determining surgical candidacy remains...

Ablating Myocardium Using Nanosecond Pulsed Electric Fields: Preclinical Assessment of Feasibility, Safety, and Durability.

Unlike conventional microsecond pulsed electrical fields that primarily target the cell membranes, nanosecond pulses are thought to primarily electroporate intracellular organelles. We conducted a comprehensive preclinical assessment of catheter-based endocardial nanosecond pulsed field ablation in swine. A novel endocardial nanosecond pulsed field ablation system was evaluated in a total of 25 swine. Using either a low-dose (5-second duration) or high-dose (15-second duration) strategy, thoracic veins and discrete atrial and ventricular sites were ablated. Predetermined survival periods were <1 (n=1), ≈2 (n=7), ≈7 (n=6), 14 (n=2), or ≈28 (n=9) days, and venous isolation was assessed before euthanasia. Safety assessments included evaluation of esophageal effects, phrenic nerve function, and changes in venous caliber. All tissues were subject to careful gross pathological and histopathologic examination. All (100%) veins (13 low-dose, 34 high-dose) were acutely isolated, and all reassessed veins (6 low-dose, 15 high-dose) were durably isolated. All examined vein lesions (10 low-dose, 22 high-dose) were transmural. Vein diameters (n=15) were not significantly changed. Of the animals assessed for phrenic palsy (n=9), 3 (33%) demonstrated only transient palsy. There were no differences between dosing strategies. Thirteen mitral isthmus lesions were analyzed, and all 13 (100%) were transmural (depth, 6.4±0.4 mm). Ventricular lesions were 14.7±4.5 mm wide and 7.1±1.3 mm deep, with high-dose lesions deeper than low-dose (7.9±1.2 versus 6.2±0.8 mm; P=0.007). The esophagus revealed nontransmural adventitial surface lesions in 5 of 5 (100%) animals euthanized early (2 days) post-ablation. In the 10 animals euthanized later (14-28 days), all animals demonstrated significant esophageal healing-8 with complete resolution, and 2 with only trace fibrosis. A novel, endocardial nanosecond pulsed field ablation system provides acute and durable venous isolation and linear lesions. Transient phrenic injury and nontransmural esophageal lesions can occur with worst-case assessments suggesting limits to pulsed field ablation tissue selectivity and the need for dedicated assessments during clinical studies.

Application of micropolar fluid model to blood flow through catheterized artery with stenosis and thrombosis

This paper presents a model of nonisothermal blood flow through a diseased arterial segment due to the presence of stenosis and thrombosis. The rheological properties of the blood in the annulus are captured by utilizing micropolar fluid model. The equation describing the blood flow and heat transfer is developed under the assumption that stenosis growth into the lumen of the artery is small as compared to the average radius of the artery. Biological processes like intimal proliferation of cells or changes in artery caliber may be activated by small growths that cause moderate stenotic blockages. Closed-form solutions for temperature, velocity, resistance impedance and wall shear stress are obtained and then utilized to estimate the impact of various physical parameters on micropolar blood flow. Graphs are plotted to illustrate variations in temperature, velocity, shear stress at the wall and resistance impedance against different controlling parameters. The results are also validated via the bvp4c approach.

Retinal vessel caliber and cognitive performance: the multi-ethnic study of atherosclerosis (MESA).

Retinal vessel calibers share anatomic and physiologic characteristics with the cerebral vasculature and can be visualized noninvasively. In light of the known microvascular contributions to brain health and cognitive function, we aimed to determine if, in a community based-study, retinal vessel calibers and change in caliber over 8years are associated with cognitive function or trajectory. Participants in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort who completed cognitive testing at Exam 5 (2010-2012) and had retinal vascular caliber measurements (Central Retinal Artery and Vein Equivalents; CRAE and CRVE) at Exam 2 (2002-2004) and Exam 5 were included. Using multivariable linear regression, we evaluated the association of CRAE and CRVE from Exam 2 and Exam 5 and their change between the two exams with scores on tests of global cognitive function (Cognitive Abilities Screening Instrument; CASI), processing speed (Digit Symbol Coding; DSC) and working memory (Digit Span; DS) at Exam 5 and with subsequent change in cognitive scores between Exam 5 and Exam 6 (2016-2018).The main effects are reported as the difference in cognitive test score per SD increment in retinal vascular caliber with 95% confidence intervals (CI). A total of 4334 participants (aged 61.6 ± 9.2years; 53% female; 41% White) completed cognitive testing and at least one retinal assessment. On multivariable analysis, a 1 SD larger CRAE at exam 5 was associated with a lower concomitant CASI score (-0.24, 95% CI -0.46, -0.02). A 1 SD larger CRVE at exam 2 was associated with a lower subsequent CASI score (-0.23, 95%CI -0.45, -0.01). A 1 SD larger CRVE at exam 2 or 5 was associated with a lower DSC score [(-0.56, 95% CI -1.02, -0.09) and -0.55 (95% CI -1.03, -0.07) respectively]. The magnitude of the associations was relatively small (2.8-3.1% of SD). No significant associations were found between retinal vessel calibers at Exam 2 and 5 with the subsequent score trajectory of cognitive tests performance over an average of 6years. Wider retinal venular caliber was associated with concomitant and future measures of slower processing speed but not with later cognitive trajectory. Future studies should evaluate the utility of these measures in risk stratification models from a clinical perspective as well as for screening on a population level.

Network response of brain microvasculature to neuronal stimulation

Neurovascular coupling (NVC), or the adjustment of blood flow in response to local increases in neuronal activity is a hallmark of healthy brain function, and the physiological foundation for functional magnetic resonance imaging (fMRI). However, it remains only partly understood due to the high complexity of the structure and function of the cerebrovascular network. Here we set out to understand NVC at the network level, i.e. map cerebrovascular network reactivity to activation of neighbouring neurons within a 500×500×500 μm3 cortical volume (∼30 high-resolution 3-nL fMRI voxels). Using 3D two-photon fluorescence microscopy data, we quantified blood volume and flow changes in the brain vessels in response to spatially targeted optogenetic activation of cortical pyramidal neurons. We registered the vessels in a series of image stacks acquired before and after stimulations and applied a deep learning pipeline to segment the microvascular network from each time frame acquired. We then performed image analysis to extract the microvascular graphs, and graph analysis to identify the branch order of each vessel in the network, enabling the stratification of vessels by their branch order, designating branches 1–3 as precapillary arterioles and branches 4+ as capillaries. Forty-five percent of all vessels showed significant calibre changes; with 85 % of responses being dilations. The largest absolute CBV change was in the capillaries; the smallest, in the venules. Capillary CBV change was also the largest fraction of the total CBV change, but normalized to the baseline volume, arterioles and precapillary arterioles showed the biggest relative CBV change. From linescans along arteriole-venule microvascular paths, we measured red blood cell velocities and hematocrit, allowing for estimation of pressure and local resistance along these paths. While diameter changes following neuronal activation gradually declined along the paths; the pressure drops from arterioles to venules increased despite decreasing resistance: blood flow thus increased more than local resistance decreases would predict. By leveraging functional volumetric imaging and high throughput deep learning-based analysis, our study revealed distinct hemodynamic responses across the vessel types comprising the microvascular network. Our findings underscore the need for large, dense sampling of brain vessels for characterization of neurovascular coupling at the network level in health and disease.

Introduction to static vessel analysis

This talk will provide you with an overview of static retinal vessel analyses. Digital photography, automated vessel segmentation and analyses have revolutionized the field of retinal vessel analyses rapidly. Retinal vessel calibre changes allow for non‐invasive study of the microcirculation in vivo. The study of the retinal microcirculation has shown its potential in cardiovascular risk assessment, allowed for observation of changes in systemic health and capture changes in physical activity. This session is aimed for those new to retinal vessel analyses using fundus images.

Esophageal biomechanics assessed by impedance planimetry (EndoFLIPTM) in healthy subjects and in patients with eosinophilic esophagitis. Normality values.

active eosinophilic esophagitis is associated with esophageal caliber, distensibility and motility changes that may be reversed with treatment. to study esophageal diameter, distensibility and contractility in healthy subjects compared to patients with eosinophilic esophagitis, both before and after treatment. a quasi-experimental study, EndoFLIP™, was used to analyze the esophageal body and esophago-gastric junction (EGJ) in all three groups, and a program was designed to obtain esophageal diameter, distensibility and contractility values. ten healthy volunteers (24-61 years, six men) and nine patients with eosinophilic esophagitis (21-52 years, seven men) were included. The esophagogastric junction distensibility index was 5.07 mm2/Hg in the control subjects, 2.40 mm2/Hg in the subjects with eosinophilic esophagitis before treatment and 2.46 mm2/Hg after treatment. The distensibility plateau was 20.02 mm, 15.43 mm and 17.41 mm, respectively, and the diameter was 21.90 mm, 17.73 mm and 18.30 mm, showing significant differences (p < 0.05), except between control subjects and patients after treatment (p = 0.079). Repetitive antegrade contractions developed in 90 % of control subjects, 66.7 % of eosinophilic esophagitis patients before treatment and 88.9 % of the latter after treatment (p > 0.05). esophago-gastric junction distensibility index, distensibility plateau and diameter values were higher in controls than in patients, although six weeks of treatment seems a short period to observe significant changes in esophageal biomechanics. Repetitive antegrade contractions are the predominant pattern in healthy subjects and eosinophilic esophagitis. We provide normality values for esophageal biomechanics, measured by impedance planimetry in our setting.

Abstract 12346: Atherosclerotic Cardiovascular Disease Risk Associated With Social Determinants of Health at Individual and Area Levels

Introduction: Adverse social determinants of health (SDOH) are associated with an increased risk for atherosclerotic cardiovascular disease (ASCVD). However, it is unclear if the ASCVD risks associated with area-level SDOH are similar to those with individual-level measures. Further, SDOH are not included in the Pooled Cohort Equations (PCEs) when estimating 10-year ASCVD risk. Studies have shown that PCEs systematically underestimate risk for socially deprived individuals. Aims To examine the association of individual- and area-level SDOH including education, income, and employment with incident ASCVD. Also, we assessed if adding SDOH to the PCEs improves risk prediction accuracy. Methods: We pooled data from four cohorts: Jackson Heart Study, Multi-Ethnic Study of Atherosclerosis, Framingham Heart Study Offspring Cohort, and Reasons for Geographic and Racial Differences in Stroke Study. We excluded participants with a history of ASCVD. Individual-level SDOH were based on participants’ self-report and area-level SDOH were derived by linking participants’ addresses to US Census tract data. We used Cox proportional hazards models to assess the associations between SDOH and ASCVD. We also assessed the changes in discrimination (Harrell’s C-index) and calibration (Integrated Brier Score) after adding SDOH to risk prediction models. Results: We analyzed data from 27,603 participants (mean age 61.4 years, 59% women, and 49% White). During a median follow-up of 13 years, 2,839 incident ASCVD events occurred. Both individual- and area-level SDOH were associated with ASCVD ( Figure, Panel A ). Adding both individual- and area-level SDOH to risk prediction modestly improved model discrimination and calibration in Black men and women ( Figure, Panels B &amp; C ), and also improved calibration in non-Black women. Conclusions: The findings suggest that SDOH may be considered in the development of future ASCVD risk assessment tools, particularly among Black individuals.