Relative Signal Intensity Research Articles

Investigation of geopolymerization and setting process of metakaolin-based geopolymer based on low-field nuclear magnetic resonance relaxometry

Water plays a crucial role in determining the porous microstructure of concrete, as its transition from liquid to bound states directly influences the final structure. To advance the commercial application of geopolymer materials, both the setting and geopolymerization processes were monitored using low-field nuclear magnetic resonance (NMR) relaxometry technology. Initially, fresh geopolymer slurries with three different liquid-to-binder ratios were prepared and monitored from their fresh to hardened states using a low-field NMR relaxation instrument over 24 hours. The distribution of the T2 relaxation signal provided information on the state and content of water molecules, indirectly revealing the microstructural evolution of the metakaolin-based geopolymer. The results indicated a significant decrease in water signal intensity, dropping by nearly 80 % within the first two hours of the geopolymerization process. Although the initial water signal intensities varied, the trends in relative water signal intensity were almost identical during the first two hours across different liquid-to-binder ratios. Specifically, for the geopolymer specimen with a liquid-to-binder ratio of 0.70, the transformation of water in capillaries to water in the gel structure began after 60 minutes of curing. Furthermore, both the start time of this transition and the geopolymerization process exhibited delays as the liquid-to-binder ratio increased. The rate of microstructural change in the geopolymer was notably significant, and the time corresponding to this change closely aligned with the setting time determined by the Vicat penetration test. Additionally, four stages akin to cement hydration were identified for the metakaolin-based geopolymer, based on the Vicat penetration testing and temperature monitoring results: (1) Dissolution, (2) Setting, (3) Acceleration, and (4) Hardening.

Machine learning-driven fluorescent sensor array using aqueous CsPbBr3 perovskite quantum dots for rapid detection and sterilization of foodborne pathogens

With the growing global concern over food safety, the rapid detection and disinfection of foodborne pathogens have become critical in public health. This study presents a novel machine learning-driven fluorescent sensor array utilizing aqueous CsPbBr3 perovskite quantum dots (PQDs) for the rapid identification and eradication of foodborne pathogens. The relative signal intensity changes (ΔRGB) generated by the sensor array were analyzed using the machine learning algorithm—Support Vector Machine (SVM). The study achieved the identification and recognition of five pathogens and their mixtures within a concentration range of 1.0 × 103 to 1.0 × 107 CFU/mL with an accuracy rate of 100 %, and the limits of detection (LOD) for the pathogens were found to be low. Additionally, the array also showed excellent performance in the identification of pathogens in tap water, achieving an accuracy rate of 100 %. Furthermore, the fluorescent sensor array was capable of inactivating the pathogens with an efficiency of over 99 % within 30 min post-detection. This development provides an efficient and reliable tool for the field of food safety detection.

Gadoxetic Acid-Enhanced MRI in Differentiating Focal Nodular Hyperplasia from Hepatocellular Adenoma in Children.

To investigate the diagnostic performance of Gd-EOB-enhanced magnetic resonance imaging (MRI) for distinguishing focal nodular hyperplasia (FNH) from hepatocellular adenoma (HCA) in children. Twenty-two patients (6 with HCA and 16 with FNH) were retrospectively included in this study. After qualitative analyses of MRI, quantitative analyses were performed by calculating the relative signal intensity ratios (SIR) between lesion and liver parenchyma both on precontrast and hepatobiliary phase images. Two equations, SIRpost-pre and liver-to-lesion contrast enhancement ratio (LLCER), using both SIRs of precontrast and hepatobiliary phase (HBP) imaging together were also calculated. The most distinguishing non-contrast-enhanced MRI feature of HCA was intralesional fat since all HCA contained fat but none of FNHs. All FNHs were iso- or hyperintense relative to the adjacent liver on HBP images, but all HCAs except one were hypointense. The mean SIRpost-pre and LLCER of FNH were significantly higher than that of HCA (p < 0,001). SIRpost-pre and LLCER provided sensitivity and specificity values of 100%. Although intralesional fat is a strong discriminative feature for distinguishing between HCA and FNH, qualitative properties of these lesions may not be enough for confident diagnosis. Gd-EOB uptake in the HBP provides high diagnostic accuracy, but overlap can be seen. SIRpost-pre and LLCER overcome the difficulties and have the best sensitivity and specificity. Although there are many similar studies in adult group, this is one of the rare studies that will contribute to the literature in the pediatric group.

Nickel foam supported CuO/Co3O4/r-GO is used as electrode material for non-enzymatic glucose sensors and high performance supercapacitors

In order to solve the problem of glucose detection in medical development and meet the urgent demand for new energy storage devices, this paper proposes a new material suitable for glucose sensing and capacitive properties. The sensor was fabricated by depositing Co3O4 nanoparticles onto nickel foam with integrated r-GO via the hydrothermal method, followed by the synthesis of CuO nanoparticles using electroplating. The detection range of the sensor is 0.3–11.3 mM. The sensor's sensitivity is 1000.3 μA mM−1 cm−2, indicating its responsiveness to changes in analyte concentration. In electrochemical test systems, Signal-to-Noise Ratio (SNR) usually represents the relative intensity of the effective current signal and the background noise, reflecting the accuracy and reliability of the measurement. When the SNR is three, the minimum detection limit is 0.431 μM, highlighting its ability to reliably detect analytes at low concentrations amidst background noise. According to electrochemical workstation tests, the sensor demonstrates robust stability. Furthermore, the electrode material proves suitable for asymmetric supercapacitor devices, when the current density is 2 Ag−1, the specific capacitance is 660.5 Fg−1. At the same time, we also explore the cyclic stability of the device, which can retain 92.3 % of its initial specific capacitance after 5000 cycles, showing its remarkable long-term stability. In addition, the prepared nanocomposites can also light the red LED light. The results show that the synthesized CuO/Co3O4/r-GO/NF electrode can be used for electrochemical glucose sensing and supercapacitors, and plays an important role as a multi-functional material in the fields of medical, food, electronics, transportation and energy, providing key technical support for a variety of applications.

An artificial intelligence-based landmark model for early detection of aortic stenosis in Cardiac MRI

Abstract Background The utilisation of ratiometric intensity measures from cardiac magnetic resonance imaging (CMR) offers a promising biomarker for the diagnosis of aortic stenosis (AS)[1]. The Ao:LV ratio, an approximation of AS severity, is determined by comparing the relative blood signal intensity in the aorta and left ventricle (LV) within three-chamber (3Ch) cine sequences[1]. In patients with AS, the blood signal intensity of aortic blood above the valve is diminished compared to that within the LV in steady-state free precession (SSFP) 3Ch CMR cine. Although the Ao:LV ratio serves as a reliable indicator of AS severity, manual computation of this ratio may encounter difficulties due to visual obstructions caused by small LV cavities or prominent papillary muscles. Purpose This study aims to leverage artificial intelligence (AI) to automate the Ao:LV ratio analysis from 3Ch SSFP cine images and introduce the Ao:LA (aorta to left atrium) ratio, thus enhancing the diagnostic accuracy for AS severity. Methods Our methodology extends the ratiometric analysis to include both Ao:LV and Ao:LA ratios in three main steps: first, developing an AI-based algorithm for automated detection and tracking of cardiac landmarks; second, using these landmarks to automatically compute regions of interest (ROIs) in the cardiac chambers; and third, training and validating classification models with 5-fold cross-validation to select the most effective for AS severity classification. The final model's performance is assessed on a holdout test set. Data for model training and evaluation were sourced from CMR scans across three hospitals and two scanner types. Results We analysed 220 patients of which 78 patients had no AS and 122 had AS (mild AS, n = 29; moderate AS; n = 35, severe AS; n = 78). Our model yielded high efficacy in classifying AS, particularly in differentiating any grade of AS from a normal classification, which is clinically relevant. The Ao:LA ratio demonstrated a stronger correlation with AS severity class than Ao:LV, suggesting a more reliable biomarker. The proposed model demonstrated robust performance in AS classification, achieving an Area Under the Curve (AUC) of 0.845 in the automated binary classification of AS at any grade. The model exhibited a precision of 0.889, recall of 0.865, and an F1 score of 0.877 on a holdout set. Conclusion By the integration of AI in automating the analysis of CMR images through a novel ratiometric approach that includes Ao:LV and Ao:LA ratios, our model significantly improves the accuracy of early AS detection. This advancement enhances imaging strategies for AS evaluation, promoting more efficient and effective use of cardiac MRI sequences as a diagnostic tool for aortic stenosis. It has the potential to be implemented in real-time scanning protocols as a clinical decision support system.AI-inferred cardiac landmarks.ROC curve delineating AS prediction.

Associations between Dynamic Contrast-Enhanced Magnetic Resonance Imaging with Histopathological Features in Cholangiocarcinoma

Introduction: The relationships between histopathology and imaging remain elusive, and investigating the underlying reasons for tumor microstructure leading to an imaging phenotype is of clinical importance. In the present study, a cross-sectional guided biopsy specimen was used to correlate prebioptic magnetic resonance imaging (MRI) with immunohistochemical staining of the histopathologic specimen using precise spatial biopsy localization. Methods: Twenty-seven patients with mass-forming cholangiocarcinoma (CCA) were included in the present analysis. All patients were imaged with a 1.5 T clinical scanner at least 1 month prior to biopsy. The contrast-enhanced dynamic sequences were analyzed with quantified signal intensities. The bioptic specimens were obtained by cross-sectional guided biopsy and further analyzed for cell density, proliferation index (Ki67), tumor-infiltrating lymphocytes, tumor-stroma ratio (TSR), and collagen. Results: There were no statistically significant correlations between MRI signal intensities and cell count, TSR, Ki67 index, and CD45 count. Only a moderate correlation was observed between relative signal intensities of the venous phase and the collagen-stained area (r = 0.40, p = 0.04). Conclusion: DCE-MRI is not associated with histopathological features in CCA. The complex interactions of tumor and tumor microenvironment are not reflected in the MRI phenotype.

Progressive T1 high-intensity plaques in carotid stenosis: Comparative MRI analyses in asymptomatic and symptomatic phases of low-grade stenosis

Background and PurposeCarotid artery stenosis, particularly the progression from asymptomatic to symptomatic lesions, is a key factor in cerebrovascular events. This study identifies predictors of symptom development in low-grade carotid stenosis (<50%), focusing on intraplaque hemorrhage (IPH) and dynamic plaque changes. Materials and MethodsWe conducted a retrospective study analyzing 30 cases of symptomatic low-grade carotid stenosis, using carotid MRI before and after symptom onset. Key measures included relative plaque signal intensity (rSI) and high-intensity plaque (HI plaque) volume. Stepwise regression analysis examined the influence of these factors on Symptomatic rSI, Symptomatic plaque volume, and NIHSS scores. ResultsSignificant increases were observed in rSI (1.32 ± 0.32 to 1.69 ± 0.25, p < 0.001) and HI plaque volume (296.4 ± 362.7 mm³ to 717.5 ± 554.9 mm³, p < 0.001) from asymptomatic to symptomatic phases. Past smoking (p = 0.008) and statin use (p = 0.04) were associated with higher Symptomatic rSI, while poor risk factor control (p = 0.03) was negatively associated. Female sex (p = 0.007) and current smoking (p = 0.009) were linked to smaller Symptomatic plaque volumes, while ischemic heart disease (p = 0.0002) and poor risk factor control (p = 0.002) predicted larger plaque volumes. Larger plaques were correlated with higher NIHSS scores (p = 0.002). ConclusionsIPH and plaque volume are key markers of progression in low-grade carotid stenosis. Poor control of cardiovascular risk factors and a history of ischemic heart disease contribute to plaque burden and stroke severity. Continuous monitoring and strict risk management are essential in reducing stroke severity in these patients.

Imaging atomic-scale magnetism with energy-filtered differential phase contrast method

We propose differential phase contrast (DPC) imaging using energy-filtered electrons to image the magnetic properties of materials at the atomic scale. Compared to DPC measurements with elastic electrons, our simulations predict about two orders of magnitude higher relative magnetic signal intensities and sensitivity to all three vector components of magnetization. Published by the American Physical Society 2024

Predicting outcomes of unruptured intracranial artery dissection with clear symptoms onset using clinical and radiological features

We investigated the clinical and radiologic predictors of unruptured symptomatic intracranial artery dissection (IAD) outcomes. Unruptured symptomatic IAD patients who underwent vessel wall magnetic resonance imaging (VW-MRI) and time-of-flight magnetic resonance angiography (TOF-MRA) within 1 month after symptom onset, followed for over 12 months were included. Baseline features predicting the clinical outcome of recurrent symptoms and radiologic outcomes of aneurysmal dilatation and occlusion were analyzed using logistic regression analysis. The Kaplan–Meier method calculated the median time to morphological stability. Patients with aneurysmal dilatation were categorized into progressive and non-progressive enlargement subgroups. Seventy-three IADs from 65 patients were included. All patients showed benign clinical course (mRS 0–1). No baseline features were predictive of recurrent symptoms. Aneurysmal dilatation was associated with increased outer diameter in baseline VW-MRI (OR, 23.15; 95% CI, 3.78–141.75, P < 0.001) and TOF-MRA (OR, 10.81; 95% CI, 2.16–53.99, P = 0.004). Occlusion was inversely associated with preserved patency in baseline VW-MRI (OR, 0.1; 95% CI, 0.01–0.74, P = 0.024) and TOF-MRA (OR, 0.14; 95% CI, 0.02–0.98; P = 0.048). The median time to morphological stability was 3.9 months (95% CI, 3.16–5.5). While baseline features did not significantly differ between aneurysmal dilatation subgroups, follow-up imaging revealed significant differences in remodeling index, normalized wall index, relative signal intensity of intramural hematoma, and presence of onion-skin appearance and intramural hematoma (all P < 0.05). Our findings suggest that while unruptured IAD presents a benign clinical outcome, follow-up imaging may be necessary to monitor the progressive enlargement of aneurysmal dilatation.

Hypothalamic Gliosis is Associated With Multiple Cardiovascular Disease Risk Factors.

Hypothalamic gliosis is mechanistically linked to obesity and insulin resistance in rodent models. We tested cross-sectional associations between radiologic measures of hypothalamic gliosis in humans and clinically relevant cardiovascular disease risk factors, as well as prevalent coronary heart disease. Using brain MRI images from Framingham Heart Study participants (N=867; mean age, 55 years; 55% females), T2 signal intensities were extracted bilaterally from the region of interest in the mediobasal hypothalamus (MBH) and reference regions in the amygdala (AMY) and putamen (PUT). T2 signal ratios were created in which greater relative T2 signal intensity suggests gliosis. The primary measure compared MBH to AMY (MBH/AMY); a positive control ratio (MBH/PUT) also assessed MBH whereas a negative control (PUT/AMY) did not. Outcomes were BMI, HDL-C, LDL-C, fasting triglycerides, and the presence of hypertension (n=449), diabetes mellitus (n=66), metabolic syndrome (n=254), or coronary heart disease (n=25). Dietary risk factors for gliosis were assessed in a prospective analysis. Statistical testing was performed using linear or logistic regression. Greater MBH/AMY T2 signal ratios were associated with higher BMI (β = 21.5 [95% CI, 15.4-27.6]; P<0.001), higher fasting triglycerides (β = 1.1 [95% CI, 0.6-1.7]; P<0.001), lower HDL-C (β = -20.8 [95% CI, -40.0 to -1.6]; P=0.034), and presence of hypertension (odds ratio, 1.2 [95% CI, 1.1-1.4]; P=0.0088), and the latter two were independent of BMI. Findings for diabetes mellitus were mixed and attenuated by adjusting for BMI. Metabolic syndrome was associated with MBH/AMY T2 signal ratios (odds ratio, 1.3 [95% CI, 1.1-1.6]; P<0.001). Model results were almost uniformly confirmed by the positive control ratios, whereas negative control ratios that did not test the MBH were unrelated to any outcomes (all P≥0.05). T2 signal ratios were not associated with prevalent coronary heart disease (all P>0.05), but confidence intervals were wide. Self-reported percentages of macronutrient intake were not consistently related to future T2 signal ratios. Using a well-established study of cardiovascular disease development, we found evidence linking hypothalamic gliosis to multiple cardiovascular disease risk factors, even independent of adiposity. Our results highlight the need to consider neurologic mechanisms to understand and improve cardiometabolic health.

Contrast-Enhanced T1-Weighted Magnetic Resonance Cholangiography Using Gadoxetate Disodium in Potential Living Liver Donors: Qualitative and Quantitative Improvement with 3-hour Delayed Imaging

BackgroundContrast-enhanced T1-weighted magnetic resonance cholangiography (CE-T1-MRC) after gadoxetate disodium administration can be used for preoperative evaluation of the bile ducts in live liver donors. This study aimed to determine whether CE-T1-MRC with 3-hour delayed imaging improves bile duct visualization both qualitatively and quantitatively compared with 20-minute delayed imaging in potential living liver donors. MethodsWe retrospectively identified 33 potential living liver donors (mean age, 30.1 years; 18 men and 15 women) who underwent preoperative CE-T1-MRC with both 20-minute delayed and 3-hour delayed imaging in a single session. The radiologist scored biliary visualization for right and left hepatic ducts (RHD and LHD), their secondary confluences and segmental bile ducts, common hepatic duct (CHD), and cystic duct (CD), and measured relative contrast ratio (rC) and relative signal intensity (rS) for RHD, LHD, and CHD. The data were analyzed using Wilcoxon's signed-rank test and paired t-test. ResultsIn qualitative analysis, duct visualization scores for RHD and LHD, their secondary confluences and segmental bile ducts, CHD, and CD were significantly higher on CE-T1-MRC with 3-hour delayed imaging than with 20-minute delayed imaging (all, P ≤ .046). In quantitative analysis, both rC and rS of RHD, LHD, and CHD were significantly higher on CE-T1-MRC with 3-hour delayed imaging than with 20-minute delayed imaging (all, P < .001). ConclusionsCE-T1-MRC with 3-hour delay imaging improves bile duct visualization both qualitatively and quantitatively in potential living liver donors.

3D-printed surfaces of titanium implant: the fibroblasts response

Ti-6Al-4V (wt%) is the most widely used titanium alloy and its additive manufactured (or 3D printed) parts with near net-shape have provided great advantages for biomedical applications. While the impact of surface roughness on the biocompatibility of 3D-printed Ti-6Al-4V part is recognized, further exploration is needed to fully understand this complex relationship. Hence, this study presents a comprehensive evaluation of as-printed Ti-6Al-4V structures, both with and without surface texturing, with particular focus on the fibroblast response. Alongside a flat surface, or as-printed surface, two different types of surface textures: diamond texture and diamond crystal texture, were meticulously designed and printed through laser powder bed fusion (LPBF). The viability, cell adhesion, and morphology of human and murine fibroblasts seeded on the surface patterns was investigated, as well as the distribution of extracellular matrix (ECM) proteins (collagen I, fibronectin). The results demonstrated that the as-fabricated surface morphologies did not impact fibroblast viability, however, a reduced density of human fibroblasts was observed on the diamond texture surface, likely owing to the upright strut structure preventing cell adhesion. Interestingly, spreading of the human, but not murine, fibroblasts was limited by the remaining partially-sintered powders. The relative intensity of ECM protein signals was unaffected, however, ECM protein distribution across the surfaces was also altered. Thus, the as-printed substrates, particularly with diamond crystal struts, present a promising avenue for the cost-effective and efficient fabrication of Ti-6Al-4V components for medical applications in the future.

Tracing semi-quantitatively the absorption and removal of organic pollutants in human hair based on secondary ion mass spectrometry

Human hair has become a promising non-invasive matrix in assessing exposure to environmental organic pollutants (OPs). However, exogenous contaminants, which were absorbed into the hair via sweat, sebum, and air particles/dust, could contribute to OP levels in hair and interfere with the precise exposure assessment. So far, the microscopic mechanisms underlying the absorption of exogenous OPs into hair remain inadequately understood. This study focused on the in-situ investigation of the diffusion processes of exogenous OPs into the hair structure using secondary ion mass spectrometry (SIMS) and isotopic tracer techniques. Results showed that the relative signal intensities of deuterium-labeled tris(1,3-dichloro-2-propyl) phosphate (TDCPP), 1-hydroxypyrene (1-OH-Pry), and bisphenol A (BPA) in the hair cortex were notably elevated after a 6-hour exposure. Diffusion coefficients of contaminants were related to their molecular weight, and absorption volumes to their water solubility and molecular structures. Exposure duration and solvent influenced the rate of diffusion and absorption volumes. The distribution of deuterium-labeled molecules in exposed hair samples after washing with two different solvents (acetone or water) was similar to that before washing. Our findings revealed the diffusion of OPs in hair cross-sections, indicating exogenous contributions to contaminants that are biologically incorporated into the hair.

Radiographic parameters and influencing factors of paraspinal muscle degeneration in healthy people

To measure the paraspinal muscle parameters, explore the characteristics of paraspinal muscles, and investigate the influence factors of paraspinal muscle degeneration in healthy people. Eighty-two healthy Chinese people were prospectively recruited between February 2020 and November 2020, including 36 males and 46 females. The age ranged from 21 to 75 years, with a mean of 48.0 years. The height ranged from 150 to 183 cm, with a mean of 165.6 cm. The body mass ranged from 43 to 100 kg, with a mean of 65.4 kg. The body mass index (BMI) ranged from 16.7 to 32.4 kg/m 2, with a mean of 23.7 kg/m 2. Parameters of the paraspinal muscles (multifidus muscle, erector spinae muscle, and psoas major muscle) at L 3, L 4, and L 5 levels were measured by MRI, including the relative total cross-sectional area (rtCSA), relative fatty cross-sectional area (rfCSA), relative signal intensity (rSI), and fatty infiltration (FI). The differences of paraspinal muscle parameters at different genders and different measurement levels were compared; Pearson or Spearman correlation analysis was used to explore the relationship between paraspinal muscle parameters and age, height, body mass, BMI. From L 3 to L 5 level, the rtCSA and rfCSA of multifidus muscle and psoas major muscle as well as the rfCSA of erector spinae muscle increased, while rtCSA of erector spinae muscle decreased. The FI and rSI of paraspinal muscles increased gradually. The parameters of paraspinal muscles at L 4 and L 5 levels were significantly different from those at L 3 levels ( P<0.05). There were significant differences in rtCSA and rfCSA of multifidus muscle, rtCSA, FI, and rSI of erector spinae muscle as well as rtCSA, rfCSA, and FI of psoas major muscle between L 4 and L 5 levels ( P<0.05). Compared with males, the rfCSA and FI of multifidus muscle, FI of erector spinae muscle, and FI of psoas major muscle were significantly higher in females, while the rtCSA of psoas major muscle was significantly lower ( P<0.05). Age was significantly negatively correlated with rtCSA of paraspinal muscles ( P<0.05), but significantly positively correlated with FI of paraspinal muscles, rfCSA and rSI of multifidus and erector spinae muscles ( P<0.05). Height was significantly negatively correlated with rfCSA and FI of paraspinal muscles ( P<0.05). The degree of paraspinal muscle degeneration increases gradually along the spine axis from head to tail. Paraspinal muscle degeneration is related to age, height, and gender. The relationship between the body mass, BMI and paraspinal muscle degeneration needs further study.

The severity of preoperative bone marrow oedema negatively influences short-term clinical outcomes following arthroscopic bone marrow stimulation for osteochondral lesions of the talus.

The purpose of this study was to study the effects of the severity of preoperative bone marrow oedema (BME) on the postoperative short-term outcomes following bone marrow stimulation (BMS) for osteochondral lesions of the talus (OLTs) and to propose a new metric that combines volume and signal density to evaluate BME. Sixty-five patients with symptomatic OLTs (<100 mm2) and preoperative BME, who received BMS in our institution from April 2017 to July 2021 with follow-ups of 3, 6and 12 months, were analysed retrospectively. The area, volumeand signal value of the BME were collected on preoperative magnetic resonance imaging. The enroled patients were divided into two groups according to the BME index (BMEI), which was defined as the product of oedema relative signal intensity and the relation of oedema volume to total talar volume. Visual analogue scale,American Orthopedic Foot and Ankle Society (AOFAS), Tegner, Foot and Ankle Ability Measure (FAAM)-activities of daily living (ADL) and Sports scores were assessed before surgery and at each follow-up. The relationship between the scores and the volume, relative signal intensityand BMEI was explored. Sixty-five patients with preoperative BME were divided into the mild (n = 33) and severe (n = 32) groups based on the BMEI. A significant difference was found for each score with the general linear model for repeated measures through all follow-up time points (p < 0.001). For the preoperative and 12-month postoperative changes of the enroled patients, 53 patients (81.5%) exceeded the minimal clinically important difference of AOFAS and 26 (40.0%) exceeded that of FAAM-sports in this study. The mild group showed significantly more improvement in AOFAS scores at 12 months (89.6 ± 7.0 vs. 86.2 ± 6.2) and FAAM-ADL scores at 6 months (83.6 ± 7.6 vs. 79.7 ± 7.7) and 12 months (88.5 ± 8.5 vs. 84.4 ± 7.7) than the severe group (p < 0.05). No significant difference of all the scores between the groups was found at 3 months. No significant correlation was found in each group between BMEI and clinical outcomes. The severity of the preoperative BME negatively affected short-term clinical outcomes following arthroscopic BMS for OLTs. Worse clinical outcomes were shown at postoperative 6 and 12 months in patients with a high preoperative BMEI, which could be a favourable parameter for assessing the severity of BME and assist in developing personalised rehabilitation plans and determining the approach and timing of surgery. Level III.

The value of susceptibility weighted imaging for immediate assessing the hyperacute outcome of MRgFUS ablation for uterine fibroids: a preliminary study

Purpose To investigate the value of susceptibility weighted imaging (SWI) for assessing the hyperacute outcome of ablation of uterine fibroids immediately after magnetic resonance-guided focused ultrasound (MRgFUS) treatment. Methods This retrospective imaging study included patients who underwent SWI and contrast-enhanced (CE) MR within 15 min of MRgFUS ablation for uterine fibroids. Two readers independently assessed the SWI features of ablative lesions and their association with the non-perfused volume (NPV) ratio. The intraclass correlation coefficient (ICC) and diagnostic value of SWI findings were calculated. Results A total of 27 uterine fibroids from 21 participants (mean age 40.1 ± 7.2 years) were analyzed. 51.9% (14/27) leiomyomas had NPV ratio ≥90%. In post-ablation SWI images, the interobserver ICC for the relative signal intensity and hypointense peripheral rim were 0.613 and 0.843, respectively (both p < .001). There was a significant difference in the prevalence of hypointense peripheral rim in leiomyomas with NPV ratio ≥90% and < 90% (p < .01), while the prevalence of relative signal intensity showed no significant difference (p > .05). When using the complete hypointense peripheral rim as a diagnostic criterion to identify NPV ratio ≥ 90%, readers 1 and 2 showed diagnostic sensitivity, specificity, and accuracy of 85.7%, 76.9%, 81.5%, and 78.6%, 76.9%, 77.8%, respectively. Conclusion Identifying a complete hypointense peripheral rim on SWI may be a potential imaging marker for assessing the hyperacute outcome of uterine fibroids ablation by MRgFUS, specifically in determining whether the NPV ratio is ≥90%.

The Diagnostic Value of Conventional MRI Combined With Diffusion-Weighted Imaging in Microprolactinomas.

Turbo spin-echo (TSE) diffusion-weighted imaging (DWI) sequences may reduce susceptibility artifacts and image distortion in sellar region, allowing better visualization of small pituitary lesions, and may be used to assist in the diagnosis of pituitary microadenomas. To explore the application value of conventional MRI combined with DWI sequences in the diagnosis of microprolactinomas. Prospective. Thirty-four patients in microprolactinomas with high signal on T2WI (HT2-PRL) group (34 females, 34 ± 7 years), 26 patients in microprolactinomas with equal or low signal on T2WI (ELT2-PRL) group (21 females, 34 ± 7 years), 35 patients with hyperprolactinemia (33 females, 32 ± 8 years), and 30 normal controls (25 females, 31 ± 7 years). TSE sequence at 3 T. Pituitary morphological parameters (such as length and volume), dynamic contrast-enhanced parameters (such as time to peak) and the apparent diffusion coefficients (ADCs) were measured in each group. ANOVA and Mann-Whitney U test were used to compare parameters among groups. Spearman's coefficient was used to evaluate the correlation between variables. ROC analysis was used to assess the performance of the parameters. A P-value <0.05 was considered statistically significant. The pituitary volume of patients in HT2-PRL, ELT2-PRL, and hyperprolactinemia group were 831.00 (747.60, 887.60), 923.63 ± 219.34, and 737.20 (606.40, 836.80) mm3. The pituitary maximum height in these three groups were 7.03 (6.43, 8.63), 8.03 ± 1.41, and 6.63 ± 1.28 mm, respectively. The lesion ADC value was significantly correlated with T2 relative signal intensity (the ratio of signal intensity of microprolactinoma or anterior pituitary to left temporal cortex) (r = 0.821). Compared with patients with hyperprolactinemia, the diagnostic efficacy of T2 relative signal intensity was higher in HT2-PRL group, with an AUC of 0.954, whereas the ADC value was the highest in ELT2-PRL group, with an AUC of 0.924. DWI sequences can be used to assist in the diagnosis of pituitary microadenomas. 1 TECHNICAL EFFICACY: Stage 2.

Intra-arterial Pressure-Enabled Drug Delivery Significantly Increases Penetration of Glass Microspheres in a Porcine Liver Tumor Model

PurposeTo test the hypothesis that Pressure-Enabled Drug Delivery (PEDD) would improve the delivery of surrogate therapeutic glass microspheres (GMs) via hepatic artery infusion to liver tumors when compared with a conventional endhole microcatheter. Materials and MethodsThe study was conducted in transgenic pigs (Oncopigs) with induced liver tumors. Tumors were infused intra-arterially with fluorescently labeled GM. PEDD with a specialized infusion device (TriNav; TriSalus Life Sciences, Westminster, Colorado) was compared with conventional endhole microcatheter delivery in both lobar and selective infusions. Near-infrared imaging was used to detect GM fluorescent signal in tumors. Image analysis with a custom deep learning algorithm (Visiopharm A/S) was used to quantitate signal intensity in relation to the tumor border. ResultsWith lobar infusions, significant increases in GM signal intensity were observed in and around tumors after PEDD (n = 10) when compared with those after conventional delivery (n = 7), with PEDD increasing penetration into the tumor by 117% (P = .004). In selective infusions, PEDD (n = 9) increased penetration into the tumor by 39% relative to conventional delivery (n = 8, P = .032). Lobar PEDD of GMs to the tumor was statistically equivalent to conventional selective delivery (P = .497). ConclusionsPEDD with a TriNav device significantly improved GM uptake in liver tumors relative to conventional infusion in both lobar and selective procedures. Lobar GM delivery with PEDD was equivalent to conventional selective delivery with an endhole device, suggesting that proximal PEDD infusions may enable effective delivery without selection of distal target vessels.

Multimodal imaging evaluation of early neurological deterioration following acute ischemic stroke.

Early neurologic deterioration occurs in up to one-third of patients with acute ischemic stroke (IS), often leading to poor functional outcomes. At present, few studies have applied amide proton transfer (APT) imaging to the evaluation of early neurological deterioration (END). This study analyzed the value of computed tomography perfusion (CTP) combined with multimodal magnetic resonance imaging (MRI) in patients with acute IS with END. This retrospective study included patients with acute IS who were admitted to the neurology inpatient department in a tertiary hospital from October 2021 to June 2023. Patients with acute IS underwent CTP within 24 hours of stroke onset and MRI [arterial spin labeling (ASL), susceptibility-weighted imaging (SWI), and APT] within 7 days. END was defined as an elevation of ≥2 points on the National Institute of Health Stroke Scale (NIHSS) within 7 days of stroke onset. Univariable and multivariable analyses were used to compare clinical and imaging biomarkers in patients with acute IS with and without END. The performance of potential biomarkers in distinguishing between the two groups was evaluated using receiver operating characteristic (ROC) curve analysis. Among the 70 patients with acute IS, 20 (29%) had END. After conducting univariable analysis, variables were selected for entry into a binary logistic regression analysis based on our univariable analysis results, previous research findings, clinical experience, and methodological standards. The results indicated that relative cerebral blood volume (CBV) on CTP, relative cerebral blood flow (CBF) on ASL, and relative signal intensity on amide proton transfer-weighted (APTw) imaging were independent risk factors for END. The areas under the ROC curves for these risk factors were 0.710 [95% confidence interval (CI): 0.559-0.861, P=0.006], 0.839 (95% CI: 0.744-0.933, P<0.001), and 0.804 (95% CI: 0.676-0.932, P<0.001), respectively. The combined area under the curve (AUC), sensitivity, and specificity of the four indices (0.941, 100%, and 78%, respectively) were higher than those of the four indices alone. CTP combined with multi-modal MRI better evaluated hemodynamics, tissue metabolism, and other relevant patient information, providing an objective basis for the clinical assessment of patients with acute IS with END and facilitating the development of accurate and personalized treatment plans.

Gallbladder fossa nodularity in the liver as observed in alcoholic liver disease patients: Analysis based on hepatobiliary phase signal intensity on gadoxetate-enhanced MRI and extracellular volume fraction calculated from routine CT data.

The purpose of this study is to further verify the concept utilizing signal intensity on hepatobiliary phase (HBP) of gadoxetate-enhanced MRI and extracellular volume fraction (ECV) calculated from CT data. Between Jan 2013 and September 2018, consecutive ALD patients who had both quadruple phase CT and gadoxetate-enhanced MRI within six months were retrospectively recruited. Those who had any intervention or disease involvement around gallbladder fossa were excluded. All images were reviewed and ECV was measured by two experienced radiologists. GBFN grades, and their HBP signal intensity or ECV relative to the surrounding background liver (BGL) were analyzed. There were 48 patients who met the inclusion criteria. There were GBFN grade 0/1/2/3 in 11/15/18/4 patients, respectively. The signal intensity on HBP relative to BGL were iso/slightly high/high in 30/15/3 patients, respectively, and ECV ratio (ECV of GBFN divided by that of BGL) was 0.88 ± 0.18, indicating there are more functioning hepatocytes and less fibrosis in GBFN than in BGL. The GBFN grades were significantly correlated to relative signal intensity at HBP (Spearman's rank correlation, p < 0.01, rho value 0.53), and ECV ratio (p < 0.01, rho value -0.45). Our results suggest GBFN in ALD would represent liver tissues with preserved liver function with less fibrosis, as compared to BGL, which are considered to support our hypothesis as shown above.