Magnetic Resonance Imaging Scans Research Articles

The volumes of amygdala subregions and peripheral programmed cell death protein-1 levels are associated with cognitive decline in individuals with knee osteoarthritis.

Persistent pain is a prominent symptom of knee osteoarthritis (KOA) and has been associated with cognitive decline in individuals with KOA. The amygdala, a complex structure consisting of nine subnuclei, and programmed cell death protein-1 (PD-1) levels play crucial roles in pain regulation and cognitive processing. This study aims to investigate the relationships among amygdala subregion volumes, cognitive function, and PD-1 levels to elucidate the underlying mechanism of cognitive decline in KOA. In this cross-sectional study, we recruited 36 patients with KOA and 25 age/gender-matched healthy controls for neuropsychological tests, structural magnetic resonance imaging scanning, and measurement of serum PD-1 levels. We used the atlas provided by FreeSurfer software to automatically segment the amygdala subnuclei. Subsequently, we compared the volumes of amygdala subregions between groups and explored their correlation with clinical scores and PD-1 levels. Compared to healthy controls, individuals with KOA exhibited significantly lower scores on global cognition tasks, such as long-delay free recall, short-delay free recall, and immediate recall tasks. Moreover, they displayed decreased volumes in lateral nucleus basal nucleus paralaminar nucleus while showing increased volumes in accessory basal nucleus, central nucleus, medial nucleus, and cortical nucleus. Within the KOA group specifically, paralaminar volume was negatively correlated with immediate recall scores; pain scores were negatively correlated with global cognition; basal volume was negatively correlated with PD-1 levels. Our findings highlight those alterations in amygdala subregion volumes along with changes in serum PD-1 levels may contribute to observe cognitive decline among individuals suffering from KOA.

Abnormal developmental of hippocampal subfields and amygdalar subnuclei volumes in young adults with heavy cannabis use: A three-year longitudinal study

BackgroundDifferences in the volumes of the hippocampus and amygdala have consistently been observed between young adults with heavy cannabis use relative to their non-using counterparts. However, it remains unclear whether the subfields of these functionally and structurally heterogenous regions exhibit similar patterns of change in young adults with long-term heavy cannabis use disorder (CUD). ObjectivesThis study aims to investigate the effects of long-term heavy cannabis use in young adults on the subregional structures of the hippocampus and amygdala, as well as their longitudinal alterations. MethodsThe study sample comprised 20 young adults with heavy cannabis use and 22 matched non-cannabis using healthy volunteers. All participants completed the Cannabis Use Disorder Identification Test (CUDIT) and underwent two T1-structural magnetic resonance imaging (MRI) scans, one at baseline and another at follow-up 3 years later. The amygdala, hippocampus, and their subregions were segmented on T1-weighted anatomical MRI scans, using a previously validated procedure. ResultsAt baseline, young adults with heavy CUD exhibited significantly larger volumes in several hippocampal (bilateral presubiculum, subiculum, Cornu Ammonis (CA) regions CA1, CA2-CA3, and right CA4-Dentate Gyrus (DG)) and amygdala (bilateral paralaminar nuclei, right medial nucleus, and right lateral nucleus) subregions compared to healthy controls, but these differences were attenuated at follow-up. Longitudinal analysis revealed an accelerated volumetric decrease in these subregions in young adults with heavy CUD relative to controls. Particularly, compared to healthy controls, significant accelerated volume decreases were observed in the right hippocampal subfields of the parasubiculum, subiculum, and CA4-DG. In the amygdala, similar trends of accelerated volumetric decreases were observed in the left central nucleus, right paralaminar nucleus, right basal nucleus, and right accessory basal nucleus. ConclusionsThe current findings suggest that long-term heavy cannabis use impacts maturational process of the amygdala and hippocampus, especially in subregions with high concentrations of cannabinoid type 1 receptors (CB1Rs) and involvement in adult neurogenesis.

Neural mechanisms associated with sleep-dependent enhancement of motor learning after brain injury.

This study aimed to examine the improvement in performance and functional magnetic resonance imaging correlates of motor learning after a daytime nap versus a period of resting wakefulness among individuals with traumatic brain injury. A sample of 32 individuals with traumatic brain injury was randomly assigned to a Sleep (N = 17) or Wake (N = 15) group after a period of training on a motor sequential learning task. A 45-min nap opportunity was provided for the Sleep group, while the Wake group watched a documentary for 45 min. Performance at the end of training was compared with their performance after the nap or wake intervention. Before and after the intervention, the motor sequential learning task was completed in the magnetic resonance imaging scanner to examine the relationship between change in performance and neural activation. Participants in the Sleep group showed significant gains from the end of training to after the intervention, whereas the Wake group did not. The functional magnetic resonance imaging results showed that relative to the Wake group, the Sleep group showed significantly decreased activation post-intervention in the anterior cingulate/paracingulate, cerebellum, cuneus/precuneus, and inferior parietal lobule including angular and supramarginal gyri. Importantly, across both groups, increased task performance at post-intervention was associated with decreased activation in the anterior cingulate/paracingulate and cerebellum. This study demonstrated the enhancing effect of a nap on motor learning performance in a sample of individuals with traumatic brain injury, with patterns of neural activation suggesting that the sequence was more automatized in the Sleep group. Strategic placement of a nap after an intense period of motor learning in the medical rehabilitation setting may have important implications for maximizing recovery after traumatic brain injury.

Role of diffusion-weighted imaging in the diagnosis of pituitary region tumors.

This study aimed to assess the role of Diffusion-Weighted Imaging (DWI) in routine pituitary Magnetic Resonance Imaging (MRI) protocols for distinguishing sellar and parasellar tumors, addressing the lack of clear guidelines in contemporary literature. A retrospective analysis of 242 pituitary MRI scans with DWI sequences was conducted in a single-center study using a 1.5T scanner and standard DWI sequence parameters. Measurements of both absolute and relative mean apparent diffusion coefficient (ADC) values, along with minimal ADC values within tumors, were performed. The adopted region of interest (ROI) based method used for these measurements was validated. Invasive pituitary adenomas exhibited significantly lower min ADC and min rADC than meningiomas, with optimal cut-off points of 0.64 (sensitivity 73%, specificity 82%) and 0.78 (sensitivity 73%, specificity 89%), respectively. Post-hemorrhagic pituitary adenomas demonstrated lower ADC values than adamantinomatous craniopharyngiomas, with an AUC of 0.893 for min rADC = 1.07, and Rathke's Cleft Cysts with mucous content, AUC 0.8 for min rADC = 1.01. Specific differentiation with high sensitivity and specificity based on diffusion parameters was observed for these tumor groups. Cystic pituitary non-functional adenomas obtained significantly lower ADC values compared to the adamantinomatous type of craniopharyngiomas and serous Rathke's Cleft Cysts (AUC up to 0.942). The study concludes that integrating DWI into routine pituitary MRI protocols enhances diagnostic accuracy in distinguishing sellar and parasellar tumors. The short scan time of one minute makes DWI a valuable and precise tool, supporting its recommendation as a standard component of pituitary MRI examinations.

Functional Liver Imaging Score Derived from Gadoxetic Acid-enhanced MRI Predicts Cachexia and Prognosis in Hepatocellular Carcinoma Patients.

Cachexia occurs in approximately half of hepatocellular carcinoma (HCC) patients as the disease progresses and is correlated with a poor prognosis. Therefore, early identification of HCC patients at risk of developing cachexia and their prognosis is crucial. This study investigated the functional liver imaging score (FLIS) derived from gadoxetic acid-enhanced magnetic resonance imaging (MRI) to identify cachexia in HCC patients and their prognosis. Pretreatment clinical and MRI data from 339 HCC patients who underwent gadoxetic acid-enhanced MRI scans were retrospectively collected. Patient weights were recorded for 6 months following the MRI scan to diagnose cachexia. The FLIS was calculated as the sum of the enhancement quality score, the excretion quality score, and the portal vein sign quality score. A Cox proportional hazards model was used to determine the significant factors affecting overall survival (OS). Multivariable logistic regression was then conducted to identify variables predicting cachexia in HCC patients, which were subsequently used to predict OS. Cox regression analysis revealed a significant association between cachexia and worse OS. Both FLIS (0-4 vs. 5-6 points) (OR, 9.20; 95% CI: 4.68-18.10; P<0.001) and α-fetoprotein >100 ng/mL (OR, 4.08; 95% CI: 2.13-7.83; P<0.001) emerged as significant predictors of cachexia in patients with HCC. Furthermore, FLIS (0-4 vs. 5-6 points) (HR, 1.73; 95% CI: 1.19-2.51; P=0.004) was significantly associated with OS. Patients in the FLIS 0-4 points group had shorter OS than those in the FLIS 5-6 points group [20 months (95% CI, 14.7-25.3) vs. 43 months (95% CI, 27.7-58.3); P=0.001]. Cachexia was associated with worse OS. The functional liver imaging score emerged as a significant predictor of cachexia in HCC patients and their prognosis.

Polygenic Risk Underlies Youth Psychopathology and Personalized Functional Brain Network Topography.

Functional brain networks are associated with both behavior and genetic factors. To uncover clinically translatable mechanisms of psychopathology, it is critical to define how the spatial organization of these networks relates to genetic risk during development. To determine the relationship between transdiagnostic polygenic risk scores (PRSs), personalized functional brain networks (PFNs), and overall psychopathology (p-factor) during early adolescence. The Adolescent Brain Cognitive Development (ABCD) Study is an ongoing longitudinal cohort study of 21 collection sites across the United States. Here, we conduct a cross-sectional analysis of ABCD baseline data, collected 2017-2018. The ABCD Study ® is a multi-site community-based study. The sample is largely recruited through school systems. Exclusion criteria included severe sensory, intellectual, medical, or neurological issues that interfere with protocol and scanner contraindications. Split-half subsets were used for cross-validation, matched on age, ethnicity, family structure, handedness, parental education, site, sex, and anesthesia exposure. Polygenic risk scores of transdiagnostic genetic factors F1 (PRS-F1) and F2 (PRS-F2) derived from adults in Psychiatric Genomic Consortium and UK Biobanks datasets. PRS-F1 indexes liability for common psychiatric symptoms and disorders related to mood disturbance; PRS-F2 indexes liability for rarer forms of mental illness characterized by mania and psychosis. (1) P-factor derived from bifactor models of youth- and parent-reported mental health assessments. (2) Person-specific functional brain network topography derived from functional magnetic resonance imaging (fMRI) scans. Total participants included 11,873 youths ages 9-10 years old; 5,678 (47.8%) were female, and the mean (SD) age was 9.92 (0.62) years. PFN topography was found to be heritable (N=7,459, 57.06% of vertices h 2 p FDR <0.05, mean h 2 =0.35). PRS-F1 was associated with p-factor (N=5,815, r=0.12, 95% CI [0.09-0.15], p<0.001). Interindividual differences in functional network topography were associated with p-factor (N=7,459, mean r=0.12), PRS-F1 (N=3,982, mean r=0.05), and PRS-F2 (N=3,982, mean r=0.08). Cortical maps of p-factor and PRS-F1 regression coefficients were highly correlated (r=0.7, p=0.003). Polygenic risk for transdiagnostic adulthood psychopathology is associated with both p-factor and heritable PFN topography during early adolescence. These results advance our understanding of the developmental drivers of psychopathology.

Highly effective grafting of poly(l-lactide) onto cellulose by microwave heating in a CO2 switchable solvent for the fabrication of biodegradable cigarette smoke adsorbent material

In this study, a CO2 switching solvent was used to dissolve cellulose, and then poly(l-lactide) (PLLA) side chain was grafted onto cellulose backbone by ring-opening polymerization of lactide under microwave heating to realize the rapid and efficient synthesis of cellulose-graft-poly(l-lactide) (C-g-PLLA). The efficiency of this method is significantly greater than that of the traditional oil bath heating system. The structure and properties of C-g-PLLA were characterized by Fourier transform infrared, Proton nuclear magnetic resonance, X-ray diffraction, Thermogravimetric analysis, and Differential scanning calorimetry. More importantly, C-g-PLLA can be rapidly degraded in both compost and lake water. It also showed good adsorption capacity for nicotine comparable to the commercial cigarette filters made from cellulose acetate. Overall, a rapid and efficient method for preparing C-g-PLLA was proposed, and the feasibility of its application in degradable cigarette smoke adsorption materials was demonstrated.

Predictors of anxiety in patients undergoing magnetic resonance imaging scans: a multicenter cross-sectional study

BackgroundMagnetic resonance imaging (MRI) is a noninvasive diagnostic tool that is commonly used to visualize soft tissues and anatomical structures. Many patients who undergo MRI scans experience anxiety. This multicenter study was conducted to assess anxiety levels experienced by patients who underwent MRI scans in the Palestinian radiology departments and identify the risk factors associated with higher levels of anxiety experienced by the patients.MethodsThis multicenter cross-sectional study was conducted in the radiology departments of different hospitals in the West Bank of Palestine using a questionnaire. The questionnaire collected different demographic data of the patients. A 100-mm visual analog scale (VAS) was used to assess the level of anxiety experienced by the patients who received MRI scans. The data were analyzed using SPSS version 28.ResultsA total of 383 patients participated in this study. Of the patients, 255 (66.6%) reported experiencing low, moderate, or high anxiety levels during the MRI scan. The median anxiety was 20.0 with an interquartile range (IQR) of 0.0–50.0 as measured using the 100-mm VAS. Higher anxiety levels were reported by the patients who were female (p-value < 0.001), unemployed (p-value = 0.009), and did not receive an MRI scan before (p-value = 0.001). In addition, the patients who received pelvis scans reported higher levels of anxiety compared to those who received scans for upper extremities (p-value = 0.031), abdomen (p-value = 0.033), pelvis (p-value = 0.043), and lower extremities (p-value = 0.016). In addition, the patients who received scans for the head/neck reported higher levels of anxiety compared to the patients who received scans for the lower extremities (p-value = 0.021).ConclusionThe findings of this study showed that a considerable proportion of the patients who received MRI scans in Palestinian hospitals experience anxiety. Radiologists and other decision-makers in the healthcare system should design effective measures to reduce anxiety and improve the experiences of patients who are female, unemployed, and those who are scheduled to receive MRI scans for the first time. Moreover, these interventions should particularly focus on the patients who are scheduled to receive scans for the pelvis and head/neck.

Deep learning-based segmentation for high-dose-rate brachytherapy in cervical cancer using 3D Prompt-ResUNet

Objective.To develop and evaluate a 3D Prompt-ResUNet module that utilized the prompt-based model combined with 3D nnUNet for rapid and consistent autosegmentation of high-risk clinical target volume (HRCTV) and organ at risk (OAR) in high-dose-rate brachytherapy for cervical cancer patients.Approach.We used 73 computed tomography scans and 62 magnetic resonance imaging scans from 135 (103 for training, 16 for validation, and 16 for testing) cervical cancer patients across two hospitals for HRCTV and OAR segmentation. A novel comparison of the deep learning neural networks 3D Prompt-ResUNet, nnUNet, and segment anything model-Med3D was applied for the segmentation. Evaluation was conducted in two parts: geometric and clinical assessments. Quantitative metrics included the Dice similarity coefficient (DSC), 95th percentile Hausdorff distance (HD95%), Jaccard index (JI), and Matthews correlation coefficient (MCC). Clinical evaluation involved interobserver comparison, 4-grade expert scoring, and a double-blinded Turing test.Main results.The Prompt-ResUNet model performed most similarly to experienced radiation oncologists, outperforming less experienced ones. During testing, the DSC, HD95% (mm), JI, and MCC value (mean ± SD) for HRCTV were 0.92 ± 0.03, 2.91 ± 0.69, 0.85 ± 0.04, and 0.92 ± 0.02, respectively. For the bladder, these values were 0.93 ± 0.05, 3.07 ± 1.05, 0.87 ± 0.08, and 0.93 ± 0.05, respectively. For the rectum, they were 0.87 ± 0.03, 3.54 ± 1.46, 0.78 ± 0.05, and 0.87 ± 0.03, respectively. For the sigmoid, they were 0.76 ± 0.11, 7.54 ± 5.54, 0.63 ± 0.14, and 0.78 ± 0.09, respectively. The Prompt-ResUNet achieved a clinical viability score of at least 2 in all evaluation cases (100%) for both HRCTV and bladder and exceeded the 30% positive rate benchmark for all evaluated structures in the Turing test.Significance.The Prompt-ResUNet architecture demonstrated high consistency with ground truth in autosegmentation of HRCTV and OARs, reducing interobserver variability and shortening treatment times.

Distinct connectivity patterns in bipolar and unipolar depression: a functional connectivity multivariate pattern analysis study

BackgroundPatients with bipolar disorder (BD) and major depressive disorder (MDD) exhibit depressive episodes with similar symptoms despite having different and poorly understood underlying neurobiology, often leading to misdiagnosis and improper treatment. This exploratory study examined whole-brain functional connectivity (FC) using FC multivariate pattern analysis (fc-MVPA) to identify the FC patterns with the greatest ability to distinguish between currently depressed patients with BD type I (BD I) and those with MDD.MethodologyIn a cross-sectional design, 41 BD I, 40 MDD patients and 63 control participants completed resting state functional magnetic resonance imaging scans. Data-driven fc-MVPA, as implemented in the CONN toolbox, was used to identify clusters with differential FC patterns between BD patients and MDD patients. The identified cluster was used as a seed in a post hoc seed-based analysis (SBA) to reveal associated connectivity patterns, followed by a secondary ROI-to-ROI analysis to characterize differences in connectivity between these patterns among BD I patients, MDD patients and controls.ResultsFC-MVPA identified one cluster located in the right frontal pole (RFP). The subsequent SBA revealed greater FC between the RFP and posterior cingulate cortex (PCC) and between the RFP and the left inferior/middle temporal gyrus (LI/MTG) and lower FC between the RFP and the left precentral gyrus (LPCG), left lingual gyrus/occipital cortex (LLG/OCC) and right occipital cortex (ROCC) in MDD patients than in BD patients. Compared with the controls, ROI-to-ROI analysis revealed lower FC between the RFP and the PCC and greater FC between the RFP and the LPCG, LLG/OCC and ROCC in BD patients; in MDD patients, the analysis revealed lower FC between the RFP and the LLG/OCC and ROCC and greater FC between the RFP and the LI/MTG.ConclusionsDifferences in the RFP FC patterns between currently depressed patients with BD and those with MDD suggest potential neuroimaging markers that should be further examined. Specifically, BD patients exhibit increased FC between the RFP and the motor and visual networks, which is associated with psychomotor symptoms and heightened compensatory frontoparietal FC to counter distractibility. In contrast, MDD patients exhibit increased FC between the RFP and the default mode network, corresponding to sustained self-focus and rumination.

The German research consortium for the study of bipolar disorder (BipoLife): a quality assurance protocol for MR neuroimaging data

BackgroundThe German multicenter research consortium BipoLife aims to investigate the mechanisms underlying bipolar disorders. It focuses in particular on people at high risk of developing the disorder and young patients in the early stages of the disease. Functional and structural magnetic resonance imaging (MRI) data was collected in all participating centers. The collection of neuroimaging data in a longitudinal, multicenter study requires the implementation of a comprehensive quality assurance (QA) protocol. Here, we outline this protocol and illustrate its application within the BipoLife consortium.MethodsThe QA protocol consisted of (1) a training of participating research staff, (2) regular phantom measurements to evaluate the MR scanner performance and its temporal stability across the course of the study, and (3) the assessment of the quality of human MRI data by evaluating a variety of image metrics (e.g., signal-to-noise ratio, ghosting level). In this article, we will provide an overview on these QA procedures and show exemplarily the influence of its application on the results of standard neuroimaging analysis pipelines.DiscussionThe QA protocol helped to characterize the various MR scanners, to record their performance over the course of the study and to detect possible malfunctions at an early stage. It also assessed the quality of the human MRI data systematically to characterize its influence on various analyses. Furthermore, by setting up and publishing this protocol, we define standards that must be considered when analyzing data from the BipoLife consortium. It further promotes a systematic evaluation of data quality and a definition of subject inclusion criteria. In the long term, it will help to increase the chance of achieving clinically relevant results.

Anatomical variants of the medial synovial fold of the posterior cruciate ligament: morphological classification based on magnetic resonance imaging of the knee.

The medial synovial fold of the posterior cruciate ligament is one of the synovial plicae of the knee joint. The objective of this study was to assess the necessity of reporting the appearance of the medial synovial fold of the posterior cruciate ligament on magnetic resonance imaging of the knee joint and its correlation with side and sex. Patients with normal knee structure on magnetic resonance imaging (MRI) scans between 2018 and 2023 were included in this retrospective study. MRI scans of the knee joints were retrospectively reviewed by two musculoskeletal radiologists independently. The medial synovial fold of the posterior cruciate ligament was divided into three types according to the imaginary line drawn between the lateral border of the medial femoral condyle and the medial tibial intercondylar tubercle. The study included 1147 patients, of whom 478 (41.7%) were female and 669 (58.3%) were male. Among these patients, 580 (50.6%) had a right knee scan, and 567 (49.4%) had a left knee scan. The age range was 15-35 years for both sexes. The frequency of the medial synovial fold types in all patients was as follows: Type A (30.1%), Type B (55.4%) and Type C (14.5%). There was a high level of agreement between the observers. There was a statistically significant difference in the frequency of medial synovial fold types between sexes, with men exhibiting a greater prevalence. Magnetic resonance imaging (MRI) of the knee joint revealed the medial synovial folds of the posterior cruciate ligament (PCL). The most common was Type B (55.4%), followed by Type A (30.1%) and Type C (14.5%) among the MSF types. No statistically significant difference was found between the right and left knees for any of the MSF types.

Functional brain connectivity changes associated with day-to-day fluctuations in affective states

Affective neuroscience has traditionally relied on cross-sectional studies to uncover the brain correlates of affects, emotions, and moods. Such findings obfuscate intraindividual variability that may reveal meaningful changing affect states. The few functional magnetic resonance imaging longitudinal studies that have linked changes in brain function to the ebbs and flows of affective states over time have mostly investigated a single individual. In this study, we explored how the functional connectivity of brain areas associated with affective processes can explain within-person fluctuations in self-reported positive and negative affects across several subjects. To do so, we leveraged the Day2day dataset that includes 40 to 50 resting-state functional magnetic resonance imaging scans along self-reported positive and negative affectivity from a sample of six healthy participants. Sparse multivariate mixed-effect linear models could explain 15% and 11% of the within-person variation in positive and negative affective states, respectively. Evaluation of these models’ generalizability to new data demonstrated the ability to predict approximately 5% and 2% of positive and negative affect variation. The functional connectivity of limbic areas, such as the amygdala, hippocampus, and insula, appeared most important to explain the temporal dynamics of affects over days, weeks, and months.

A compressible high-sensitivity flexible sensor array for real-time motion artifact detection in magnetic resonance imaging

Magnetic Resonance Imaging (MRI) serves as a critical tool in modern medical diagnosis, and its accuracy is directly linked to patient treatment and recovery. However, unintentional patient movement during MRI scans often results in motion artifacts on the images, significantly compromising the precision of diagnosis. Traditional solutions typically involve identifying and addressing these issues after the scanning sequence is completed, leading to significant resource waste and delays in patient treatment. Here, we propose a flexible tactile sensor array system based on triboelectric nanogenerators (TENGs) for real-time monitoring of head motion artifacts in MRI. The unique design of the tactile sensor structure, operating in a dual-electrode mode, maintains high sensitivity and a wide response range, even with a minimal surface area. The advantage of TENG is the wide range of material choices, ensuring that a proper selection will not interfere with MRI during application. By integrating TENG sensor technology and control program systems, this solution provides a novel approach for monitoring head motion artifacts in MRI. On the basis of ensuring patient comfort, it has saved the time and money costs of monitoring, improved the efficiency of detection, and demonstrated significant potential in the field of medical imaging.

Evaluation of Trunk Oblique Muscle Activities in Baseball Batters Using T2-Weighted Magnetic Resonance Imaging.

Takuya, Y, Taro, I, Chihiro, K, Mana, O, Takahiro, O, and Masako, H. Evaluation of trunk oblique muscle activities in baseball batters using T2-weighted magnetic resonance imaging. J Strength Cond Res XX(X): 000-000, 2024-This study investigated abdominal oblique muscle activity using T2-weighted imaging in baseball batting. For this purpose, 17 baseball batters (21.6 ± 2.7 years, 173.9 ± 4.0 cm, 77.5 ± 7.6 kg) performed 100 toss-batting trials. Before and after toss-batting, 3 Tesla magnetic resonance imaging scans were performed to obtain the T2 values of the 4 abdominal external and internal oblique muscle pairs. The results showed that the T2 values of all abdominal oblique muscles were significantly increased after the 100 trials (p < 0.05), with no differences in these increases between the muscles. The rate of change in the T2 values was 1.0 ± 3.9% and 4.2 ± 5.2% for the external and internal oblique muscles on the pitcher's side and 3.2 ± 5.1% and 0.9 ± 2.5% for the external and internal oblique muscles on the catcher's side, respectively. These findings indicate that the activity levels of all abdominal oblique muscles during baseball battings are similar and lower than those of the agonist muscles used during resistance exercise and sprinting. These findings suggest that baseball batting is a low-intensity exercise of the abdominal oblique muscles, but adequate training of each abdominal oblique muscle may improve batting performance and prevent injury.

Assessment of spectral ghost artifacts in echo-planar spectroscopic micro-imaging with flyback readout

In this work, echo-planar spectroscopic imaging (EPSI) with flyback readout gradient-echo train was implemented in a preclinical MR scanner. The aim of this study is to visualize and quantify the ghost spectral lines produced by two, three and four interleaved echo trains with different amplitudes of the readout gradients, and to investigate the feasibility of the flyback data acquisition in micro-imaging of small animals. Applied multi-slice EPSI sequence utilizes asymmetric gradient-echo train that combines the shortest possible rewind gradients with readout gradients. It simplifies data processing because all echoes are acquired with the same polarity of the readout gradient. The approach with four interleaved gradient-echo trains and with four echoes in each train provides broad spectral bandwidth in combination with narrow receiver bandwidth and a good water-fat signal separation. It improves signal-to-noise ratio without the undesired consequence of water-fat shift artifacts that are eliminated during data processing. Position, number, and intensity of the ghost spectral lines can be controlled by the suitable choice of spectral bandwidth, number of echo train interleaves, and the number of echoes in each interleave. This study demonstrates that high-spatial resolution EPSI with interleaved flyback readout gradient-echo trains is feasible on standard preclinical scanners.

Optimal Timing for Advanced Imaging in Childhood Bone and Joint Infection

Objective: Advanced imaging in the management of childhood bone and joint infection (BJI) has the potential to improve disease outcomes. Knowledge about the optimal timing for magnetic resonance imaging (MRI) in relation to both surgically and nonsurgically managed BJI is limited. This study examines the impact of MRI timing on number of surgeries, length of stay (LOS), hospitalization cost, and disease recurrence in childhood BJI. Methods: This is a retrospective review of patients younger than 16 years with acute hematogenous osteomyelitis (AHO) or septic arthritis (SA) treated in the Auckland region from 2018 to 2023. Cases undergoing MRI as part of diagnostic workup were included. Treatment, hours between admission and MRI, LOS, hospitalization cost, and infection recurrence were assessed. Results: There were 563 cases of BJI, of which 390 met the inclusion criteria. Cases were primarily AHO (85%). The percentage of cases having MRI increased over time from 54% (2018) to 80% (2023). Locally disseminated infections such as subperiosteal abscess or adjacent septic arthritis occurred in 48%. Children with preoperative (n = 145) versus postoperative MRI (n = 60) had a lower reoperation rate (33% vs 77%, P = 0.001) and shorter LOS (14.1 vs 22.4 d, P = 0.002). Hospitalization costs appeared lower but did not differ statistically ($59,419 vs $159,353, P = 0.12). In nonoperative cases, LOS was shorter if an MRI occurred within 48 hours of admission (7.3 vs 10 d, P = 0.03). Disease recurrence was not associated with MRI timing. Conclusion: Overall, children with BJI who underwent MRI scans before surgery had lower reoperation rates. Children receiving MRIs within 48 hours of admission had shorter LOS.

Abnormal resting-state functional connectivity of hippocampal subregions in type 2 diabetes mellitus-associated cognitive decline.

Type 2 diabetes mellitus (T2DM) over time predisposes to inflammatory responses and abnormalities in functional brain networks that damage learning, memory, or executive function. The hippocampus is a key region often reporting connectivity abnormalities in memory disorders. Here, we investigated peripheral inflammatory responses and resting-state functional connectivity (RSFC) changes characterized of hippocampal subregions in type 2 diabetes-associated cognitive decline (T2DACD). The study included 16 patients with T2DM, 16 patients with T2DACD and 25 healthy controls (HCs). Subjects were assessed for cognitive performance, tested for the expression of inflammatory factors IL-6, IL-10 and TNF-α in peripheral serum, underwent resting-state functional magnetic resonance imaging scans, and analyzed for RSFC using the hippocampal subregions as seeds. We also calculated the correlation between cognitive performance and RSFC of hippocampal subregion, and analyzed the significantly altered RSFC values of T2DACD for Receiver Operating Characteristic (ROC) analysis. T2DACD patients showed a decline in their ability to complete cognitive assessment scales and experimental paradigms, and T2DM did not show abnormal cognitive performance. IL-6 expression was increased in peripheral serum in both T2DACD and T2DM. Compared with HCs, T2DACD showed abnormalities RSFC of the left anterior hippocampus with left precentral gyrus and left angular gyrus. T2DM showed abnormalities RSFC of the left middle hippocampus with right medial frontal gyrus, right anterior and middle hippocampus with left precuneus, left anterior hippocampus with right precuneus and right posterior middle temporal gyrus. Compared with T2DM, T2DACD showed abnormalities RSFC of the left posterior hippocampus and right middle hippocampus with left precuneus. In addition, RSFC in the left posterior hippocampus with left precuneus of T2DACD was positively correlated with Flanker conflict response time (r=0.766, P=0.001). In the ROC analysis, the significantly altered RSFC values of T2DACD achieved significant performance. T2DACD showed a significant decrease in attentional inhibition and working memory, peripheral pro-inflammatory response increased, and abnormalities RSFC of the hippocampal subregions with default mode network and sensory-motor network. T2DM did not show a significant cognitive decline, but peripheral pro-inflammatory response increased and abnormalities RSFC of the hippocampus subregions occurred in the brain. In addition, the left precuneus may be a key brain region in the conversion of T2DM to T2DACD. The results of this study may provide a basis for the preliminary diagnosis of T2DACD.

The primary systemic vasculitis associated optic neuritis: a retrospective analysis in a single center over 10 years

ObjectivesTo investigate the clinical and image characteristics of primary systemic vasculitis-associated optic neuritis patients.MethodsThis is a retrospective study. The patients clinically diagnosed with primary system vasculitis-induced optic neuritis were recruited from March 2013 to December 2023. All cases received orbital magnetic resonance imaging scans were analyzed. The ocular findings, systemic manifestations, laboratory data and prognosis were reviewed retrospectively. In addition, the related literature was reviewed.ResultsFourteen patients (21 eyes), including 10 men and 4 women, were enrolled in this study. The ages ranged from 30 to 86 years in this cohort. Orbits MRI detects the enlargement and/or enhancement of the optic nerve. Cases 1–5 reported a confirmed diagnosis of Takayasu’s arteritis, and cases 6–8 had giant cell arteritis. Cases 9–13 were antineutrophil cytoplasmic antibody-associated vasculitis. Case 14 was Cogan’s syndrome. Mult organs and tissues, such as the kidneys, heart, paranasal sinuses, meninges, and respiratory system, were involved. In all of the 14 involved patients, the disease onset was either during the fall or winter season. There were no or only slight improvements in visual activity after conventional therapies.ConclusionsThe autoantibodies’ attack on the optic nerve, ischemic damage, or destruction of the blood–brain barrier may be the potential pathogenesis of vasculitis-associated optic neuritis. Even with prompt and aggressive clinical interventions, the prognosis remains unsatisfactory.

Progression of hippocampal subfield atrophy and asymmetry in Alzheimer's disease.

Alzheimer's disease (AD) affects the hippocampus during its progression, but the specific observable changes of hippocampal subfields during disease progression remain poorly understood. In this study, we employed an event-based model (EBM) to determine the sequence of occurrence of hippocampal subfield atrophy in mild cognitive impairment (MCI) and AD cohorts. Subjects (207) were included: 86 MCI, 53 AD, and 68 healthy controls from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Participants underwent structural magnetic resonance imaging (MRI) scans to analyse the hippocampal subfields. We assigned each patient to a specific EBM stage, based on the number of their abnormal subfields. A combination of 2-year follow-up MRI scans were applied to demonstrate the longitudinal consistency and utility of the model's staging system. The model estimated that the earliest atrophy occurs in the hippocampal fissure, then spreading to other subregions in both MCI and AD. We identified a marked divergence between the sequences of left and right hippocampal subfields atrophy, so inter-hemispheric asymmetry pattern was further analysed. The sequence of asymmetry index (AI) increases beginning in the molecular and granule cell layers of the dentate gyrus (GC-ML-DG), cornus ammonis (CA) 4, and the molecular layer (ML). Longitudinal analysis confirms the efficacy of the model. In addition, the model stages were significantly correlated with patients' memory scores (p < .05). Collectively, we used a data-driven method to provide new insight into AD hippocampal progression. The present model could aid in understanding of the disease stages, as well as tracking memory decline.