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Peripapillary Retinal Pigment Epithelium Layer Shape Changes From Acetazolamide Treatment in the Idiopathic Intracranial Hypertension Treatment Trial
摘要： PURPOSE. Recent studies indicate that the amount of deformation of the peripapillary retinal pigment epithelium and Bruch’s membrane (pRPE/BM) toward or away from the vitreous may reflect acute changes in cerebrospinal fluid pressure. The study purpose is to determine if changes in optic-nerve-head (ONH) shape reflect a treatment effect (acetazolamide/placebo + weight management) using the optical coherence tomography (OCT) substudy of the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) at baseline, 3, and 6 months. METHODS. The pRPE/BM shape deformation was quantified and compared with ONH volume, peripapillary retinal nerve fiber layer (pRNFL), and total retinal (pTR) thicknesses in the acetazolamide group (39 subjects) and placebo group (31 subjects) at baseline, 3, and 6 months. RESULTS. Mean changes of the pRPE/BM shape measure were significant and in the positive direction (away from the vitreous) for the acetazolamide group (P < 0.01), but not for the placebo group. The three OCT measures reflecting the reduction of optic disc swelling were significant in both treatment groups but greater in the acetazolamide group (P < 0.01). CONCLUSIONS. Change in the pRPE/BM shape away from the vitreous reflects the effect of acetazolamide + weight management in reducing the pressure differential between the intraocular and retrobulbar arachnoid space. Weight management alone was also associated with a decrease in optic nerve volume/edema but without a significant change in the pRPE/BM shape, implying an alternative mechanism for improvement in papilledema and axoplasmic flow, independent of a reduction in the pressure differential.
关键词： optical coherence tomography,Bruch’s membrane,shape analysis,papilledema,intracranial hypertension
更新于2025-09-23 15:23:52
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Hypertension Assessment Using Photoplethysmography: A Risk Stratification Approach
摘要： Hypertension is a common chronic cardiovascular disease (CVD). Early screening and diagnosis of hypertension plays a major role in its prevention and in the control of CVDs. Our study discusses the early screening of hypertension while using the morphological features of photoplethysmography (PPG). Numerous morphological features of PPG and its derivative waves were defined and extracted. Six types of feature selection methods were chosen to screen and evaluate these PPG morphological features. The optimal features were comprehensively analyzed in relation to the physiological processes of the cardiovascular circulatory system. Particularly, the intrinsic relation and physiological significance between the formation process of systolic blood pressure (SBP) and PPG morphology features were analyzed in depth. A variety of linear and nonlinear classification models were established for the comparison trials. The F1 scores for the normotension versus prehypertension, normotension and prehypertension versus hypertension, and normotension versus hypertension trials were 72.97%, 81.82%, and 92.31%, respectively. In summary, this study established a PPG characteristic analysis model and established the intrinsic relationship between SBP and PPG characteristics. Finally, the risk stratification of hypertension at different stages was examined and compared based on the optimal feature subset.
关键词： Hypertension,photoplethysmograph,feature selection,systolic blood pressure,risk classification
更新于2025-09-23 15:22:29
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Arterial Stiffness Assessment by Shear Wave Elastography and Ultrafast Pulse Wave Imaging: Comparison with Reference Techniques in Normotensives and Hypertensives
摘要： Shear wave elastography and ultrafast imaging of the carotid artery pulse wave were performed in 27 normotensive participants and 29 age- and sex-matched patients with essential hypertension, and compared with reference techniques: carotid–femoral pulse wave velocity (cfPWV) determined via arterial tonometry and carotid stiffness (carPWV) determined via echotracking. Shear wave speed in the carotid anterior (a-SWS) and posterior (p-SWS) walls were assessed throughout the cardiac cycle. Ultrafast PWV was measured in early systole (ufPWV-FW) and in end-systole (dicrotic notch, ufPWV-DN). Shear wave speed in the carotid anterior appeared to be the best candidate to evaluate arterial stiffness from ultrafast imaging. In univariate analysis, a-SWS was associated with carPWV (r = 0.56, p = 0.003) and carotid-to-femoral PWV (r = 0.66, p < 0.001). In multivariate analysis, a-SWS was independently associated with age (R2 = 0.14, p = 0.02) and blood pressure (R2 = 0.21, p = 0.004). Moreover, a-SWS increased with blood pressure throughout the cardiac cycle and did not differ between normotensive participants and patients with essential hypertension when compared at similar blood pressures.
关键词： Hypertension,Vascular ultrasound,Arterial stiffness,Pulse wave velocity,Shear wave elastography,Ultrafast imaging,Echotracking
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Krakow, Poland (2018.10.16-2018.10.18)] 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - A Novel MRA-Based Framework For Detecting Correlation Between Cerebrovascular Changes and Mean Arterial Pressure
摘要： Systemic hypertension is a signi?cant contributor for strokes and cognitive impairment and is a leading cause of mortality in the USA. Changes in cerebral vascular diameter and cerebral perfusion pressure have been reported to precede elevation of systemic blood pressures. A novel, non-invasive Time-of-Flight - Magnetic Resonance Angiography (TOF-MRA) based framework for detection of cerebrovascular changes is presented. The proposed framework analyzes brain TOF-MRA data to quantify changes in cerebral vascular diameter and cerebral perfusion pressure. The framework has three major steps: 1) Adaptive segmentation to extract large and small diameter cerebral vessels from TOF-MRA images using both appearance and 3-D spatial information of the vascular system; 2) Estimation of the Cumulative Distribution Function (CDF) of the 3-D distance map of the cerebral vascular system, which represents the changes in diameter of the 3-D vascular system ; and 3) Statistical and correlation analysis that measured the effect of Mean Arterial Pressure (MAP) on blood vessels’ diameter changes. The ef?cacy of the framework was evaluated using MRA images and blood pressure (BP) measurements obtained from 15 patients (M=8, F=7, Age=49.2±7.3 years) on Day 0 and Day 700. The framework had a dice similarity coef?cient of 92.23%, a sensitivity of 94.8% and a speci?city of ～ 99% in detecting elevated vascular pressures compared to ground truth. Statistical analysis demonstrated an inverse relationship between blood vessels diameters and MAP. This correlation was valid for both upper (above the circle of Willis) and lower (circle of Willis and below) sections of the brain. The proposed methodology may be used to quantify changes in cerebral vasculature and cerebral perfusion pressure non-invasively through MRA image analysis, which may be a useful tool for clinicians to optimize medical management of pre-hypertension and hypertension.
关键词： Vessel Diameter,Skull Stripping,CDF,Automatic Segmentation,Mean Arterial Pressure,Blood Vessels,MRA,Hypertension,Median Vascular Radius
更新于2025-09-23 15:22:29
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Effect of Apraclonidine and Diclofenac on Early Changes in Intraocular Pressure After Selective Laser Trabeculoplasty
摘要： Précis: Adjuvant diclofenac and apraclonidine eye drop given in conjunction with selective laser trabeculoplasty (SLT) do not significantly impact medium-term intraocular pressure (IOP) reduction compared with placebo, but apraclonidine can be used to blunt immediate postlaser pressure spikes. Purpose: There is limited high-grade evidence guiding the choice of eye drops given before and after SLT. The authors chose to measure IOP during the first 24 hours, at 1 week, 6 weeks, and 6 months after SLT, and compare the effect of apraclonidine before SLT and diclofenac after SLT, with placebo. Materials and Methods: In this double-blind, randomized, placebo-controlled trial, patients with open-angle glaucoma or ocular hypertension referred for SLT were recruited between 2016 and 2018. Patients were randomized to receive either apraclonidine pre-SLT with placebo post-SLT, placebo pre-SLT with diclofenac post-SLT, or placebo before and after SLT. Results: Sixty eyes from 35 patients were treated with 360-degree SLT. Twenty-four-hour IOP measurements with patient self-monitoring after SLT demonstrated a moderate IOP spike at 1 hour and 2 hours post-SLT in the placebo and diclofenac study arms (mean = +4.05 ± 0.58 mm Hg and +4.47 ± 0.73, respectively, P < 0.001 vs. pre-SLT IOP), which was prevented by apraclonidine (mean = ?2.41 ± 0.88 mm Hg, P < 0.0001 vs. other study arms post-SLT). There were no significant differences between the 3 arms of the study on the long-term IOP reduction achieved by SLT (6 wk: P = 0.51, 6 mo: P = 0.42). Conclusions: Neither the use of apraclonidine before SLT nor diclofenac after SLT significantly influenced the IOP reduction induced by SLT. Except for a slight and transient reduction in intraocular inflammation, there was no beneficial effect of diclofenac on early IOP changes or the degree of patient discomfort relative to placebo.
关键词： open-angle glaucoma,non–steroidal anti-inflammatory,selective laser trabeculoplasty,intraocular pressure,ocular hypertension
更新于2025-09-23 15:21:01
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<p>Assessing Renal Microvascular Reactivity by Laser Speckle-Contrast Imaging in Angiotensin-II-Treated Mice</p>
摘要： The kidney is one of the main organs affected by microvascular damage wrought by hypertension. We developed an approach to investigate renal microcirculatory disturbance in live mice by measuring post-occlusive reactive hyperemia (PORH), a reactivity test exploring endothelial and neuro-microvascular functioning. Laser speckle-contrast analysis (LASCA) assesses microvascular blood flow; it provides real-time images of spatial and temporal blood flow dynamics. We compared basal blood flow and PORH test between control and angiotensin-II-treated mice (Ang-II) to validate the model.
关键词： hypertension,renal microcirculation,laser speckle-contrast analysis,microvascular reactivity
更新于2025-09-23 15:21:01
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Visual Field Outcomes from the Multicenter, Randomized Controlled Laser in Glaucoma and Ocular Hypertension Trial
摘要： To compare visual field outcomes of ocular hypertensive and glaucoma patients treated with Medicine-1st against those treated with selective laser trabeculoplasty (SLT, Laser-1st). Secondary analysis of patients from Laser in Glaucoma and Ocular Hypertension (LiGHT), a multicentre randomised controlled trial. 344 patients (588 eyes) treated with Medicine-1st, 344 patients (590 eyes) treated with Laser-1st. Visual fields (VFs) were measured using standard automated perimetry and arranged in series (median length and duration: 9 VFs over 48 months). Hierarchical linear models were used to estimate pointwise VF progression rates, which were then averaged to produce a global progression estimate for each eye. Proportions of points and patients in each treatment group with fast (< -1 dB/y) or moderate (< -0.5 dB/y) progression were compared using log-binomial regression. Pointwise and global progression rates of total deviation (TD) and pattern deviation (PD). A greater proportion of eyes underwent moderate or fast TD progression in the Medicine-1st group compared with the Laser-1st group (26.2% vs. 16.9%; Risk Ratio, RR = 1.55 [1.23, 1.93], P < 0.001). A similar pattern was observed for pointwise rates (Medicine-1st 26.1% vs. Laser-1st 19.0%, RR = 1.37 [1.33, 1.42], P < 0.001). A greater proportion of pointwise PD rates were categorised as moderate or fast in the Medicine-1st group (Medicine-1st 11.5% vs. Laser-1st 8.3%, RR = 1.39 [1.32, 1.46], P < 0.001). There was no statistical difference in the proportion of eyes that underwent moderate or fast PD progression (Medicine-1st 9.9% vs. Laser-1st 7.1%, RR = 1.39 [0.95, 2.03], P = 0.0928). A slightly larger proportion of ocular hypertensive and glaucoma patients treated with Medicine-1st underwent rapid VF progression compared with those treated with Laser-1st.
关键词： Medicine-1st,Laser-1st,Glaucoma,Visual field,Ocular hypertension,Selective laser trabeculoplasty
更新于2025-09-23 15:21:01
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Time course of bilateral microglial activation in a mouse model of laser-induced glaucoma
摘要： Microglial activation is associated with glaucoma. In the model of unilateral laser-induced ocular hypertension (OHT), the time point at which the inflammatory process peaks remains unknown. Different time points (1, 3, 5, 8, and 15 d) were compared to analyze signs of microglial activation both in OHT and contralateral eyes. In both eyes, microglial activation was detected in all retinal layers at all time points analyzed, including: i) increase in the cell number in the outer segment photoreceptor layer and plexiform layers (only in OHT eyes) from 3 d onward; ii) increase in soma size from 1 d onward; iii) retraction of the processes from 1 d in OHT eyes and 3 d in contralateral eyes; iv) increase in the area of the retina occupied by Iba-1+ cells in the nerve fiber layer/ganglion cell layer from 1 d onward; v) increase in the number of vertical processes from 1 d in contralateral eyes and 3 d in OHT eyes. In OHT eyes at 24 h and 15 d, most Iba-1+ cells were P2RY12+ and were down-regulated at 3 and 5 d. In both eyes, microglial activation was stronger at 3 and 5 d (inflammation peaked in this model). These time points could be useful to identify factors implicated in the inflammatory process.
关键词： Microglial activation,retinal layers,glaucoma,inflammation,ocular hypertension
更新于2025-09-23 15:19:57
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Optic Nerve Head Volumetry by Optical Coherence Tomography in Papilledema Related to Idiopathic Intracranial Hypertension
摘要： Purpose: Idiopathic intracranial hypertension (IIH) leads to optic nerve head swelling and optic atrophy if left untreated. We wanted to assess an easy to perform volumetric algorithm to detect and quantify papilledema in comparison to retinal nerve fiber layer (RNFL) analysis using optical coherence tomography (OCT). Methods: Participants with and without IIH underwent visual acuity testing at different contrast levels and static perimetry. Spectralis-OCT measurements comprised standard imaging of the peripapillary RNFL and macular ganglion cell layer (GCL). The optic nerve head volume (ONHV) was determined using the standard segmentation software and the 3.45 mm early treatment diabetic retinopathy study (ETDRS) grid, necessitating manual correction within Bruch membrane opening. Three neuro-ophthalmologists graded fundus images according to the Frisén scale. A mixed linear model (MLM) was used to determine differences between study groups. Sensitivity and specificity was evaluated using the area under the receiver-operating characteristic (ROC). Results: Twenty-one patients with IIH had an increased ONHV of 6.46 ± 2.36 mm3 as compared to 25 controls with 3.20 ± 0.25 mm3 (P < 0.001). The ONHV cutoff distinguishing IIH from controls was 3.97 mm3 (i.e. no patient with IIH had an ONHV below and no healthy individual above this value). The area under the curve (AUC) for ONHV was 0.99 and for the RNFL at 3.5 mm 0.90. The Frisén scale grading correlated higher with the ONHV (r = 0.90) than with the RNFL thickness (r = 0.68). ONHV measurements were highly reproducible in both groups (coefficient of variation <0.01%). Conclusions: OCT-based volumetry of the optic nerve head discriminates very accurately between individuals with and without IIH. It may serve as a useful adjunct to the rating with the subjective and ordinal Frisén scale. Translational Relevance: A simple OCT protocol run on the proprietary software of a commercial OCT device can reliably discriminate between normal optic nerve heads or pseudo-papilledema and true papilledema while being highly reproducible. Our normative data and OCT preset may be used in further clinical studies.
关键词： optical coherence tomography,pseudotumor cerebri syndrome,idiopathic intracranial hypertension,papilledema,optic nerve head volume
更新于2025-09-23 15:19:57
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Visible-light-initiated Sonogashira coupling reactions over CuO/TiO <sub/>2</sub> nanocomposites
摘要： Magnesium lithospermate B (MLB) shows multiple biological activities including anti-oxidation and anti-proliferation in various diseases. However, the function of MLB in pulmonary arterial hypertension (PAH) is still unknown. This study aims to investigate the effect of MLB on hypoxia-induced phenotypic transformation of pulmonary arterial smooth muscle cells (PASMCs) and the underlying mechanisms. SD rats (or PASMCs) were exposed to 10% O2 for 3 weeks ( or 3% O2 for 48h) along with MLB or NADPH oxidase （NOX） inhibitor intervention. The effects of MLB on hemodynamics, pulmonary vascular remodeling and phenotypic transformation of PASMCs were observed first. Then, its effects on the protein levels of NOX (NOX2 and NOX4), ERK and p-ERK were examined. The results showed that MLB prevented the elevation in right ventricular systolic pressure and the increase in ratio of wall thickness to vessel external diameter of pulmonary arteries in PAH rats, and attenuated phenotypic transformation of PASMCs (decrease in α-smooth muscle actin while increase in osteopontin), accompanied by downregulation of NOX (NOX2 and NOX4) protein levels, decrease of ROS and H2O2 production, and suppression of the phosphorylation of ERK. NOX inhibitor (VAS2870) achieved similar results to that of MLB did in the hypoxia-treated PASMCs. Based on the observations, we conclude that MLB is able to prevent phenotypic transformation of pulmonary arteries in hypoxic PAH rats through suppression of NOX/ROS/ERK pathway, and MLB might have the potentials in PAH therapy.
关键词： pulmonary vascular remodeling,pulmonary arterial hypertension,Magnesium lithospermate B,NADPH oxidase,phenotypic transformation
更新于2025-09-19 17:15:36