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Background: Ectopic fat deposition, involving lipid infiltration within organs and fat accumulating surrounding organs, plays a crucial role in the development of metabolic abnormalities in obesity. Current imaging measurements of obesity primarily focus on lipid infiltration within liver, neglecting fat deposition in other areas. This study aims to explore the methods of measuring and correlating different types of abdominal ectopic fat deposition in obese patients using magnetic resonance imaging (MRI) and ultrasound techniques, and to investigate the relationship between these fat parameters and obesity-related metabolic markers. Methods: Abdominal ectopic fat deposition including liver fat content, mesenteric fat thickness (MFT), perirenal fat thickness (PrFT) and preperitoneal fat thickness (PFT) were measured in 220 overweight/obese patients using both MRI and ultrasound techniques. Correlation analysis validated the concordance of fat parameters at specific sites between the two imaging methods and identified the cutoff values of hepatic attenuation coefficient (AC) for diagnosis of liver steatosis. Additionally, we investigated the correlation between fat parameters by both methods and obesity-related metabolic markers. Results: Ultrasonic measurement of PrFT and hepatic AC both had high correlation with PrFT (r = 0.829, p < 0.001) and hepatic Proton-density fat fraction (PDFF, r = 0.822, p < 0.001) measured via MR. Hepatic AC cutoff values for diagnosing mild, moderate, and severe fatty liver were 0.705 dB/cm/MHz (AUC = 0.922), 0.755 dB/cm/MHz (AUC = 0.923), and 0.875 dB/cm/MHz (AUC = 0.890) respectively. Hepatic AC correlated significantly with AST and ALT (r = 0.477 ~ 0.533, p < 0.001). MFT measured by ultrasound were positively associated with glycated hemoglobin (r = 0.324 ~ 0.371, p < 0.001) and serum triglyceride levels (r = 0.303 ~ 0.353, p < 0.001). PrFT measured by both methods showed significant positive correlations with serum creatinine levels (r = 0.305 ~ 0.308, p < 0.001). Conclusions: Both MRI and ultrasound demonstrate metabolic correlations in quantifying mesenteric, hepatic, and perirenal fat. In addition to assessment of liver fat content, the measurements of ectopic fat deposition by MRI or ultrasound are a simple and crucial way for comprehensive fat evaluation in individuals with overweight/obesity. [ABSTRACT FROM AUTHOR]

The intravascular large B cell lymphoma (IVLBCL) is a rare subtype of lymphoma. The IVBCL is usually found with systemic involvement, with a relative predilection for skin and the central nervous system (CNS), followed by a rapidly progressive course and poor prognosis with a high mortality rate. IVLBCL is difficult to diagnose based on conventional MRI alone. Herein, we presented a previously healthy 59-year-old woman who developed hemiparesis and altered mental status after her reinfection of SARS-CoV-2. The initial MRI revealed non-enhancing lesions in the splenium of the corpus callosum (CC), periventricular, and bilateral subcortical white matter with hyperintensity on diffusion weighted imaging (DWI). The patient was diagnosed with subacute infarction, and she was treated with antithrombotic therapy. Her neurological symptoms continued to deteriorate, and she developed unconsciousness. Her CSF test showed elevated white cell count and positive oligoclonal bands. The follow-up MRI was scanned 16 days later. Compared to the initial MRI, the periventricular and bilateral subcortical lesions enlarged on conventional MRI. The post-contrast 3D black blood Cube images demonstrated multiple parenchymal and diffuse meningeal enhancements and 3D arterial spin labeling showed increased perfusion in the CC splenium. These findings suggested the differential diagnosis of acute demyelinating encephalomyelitis (ADEM) after SARS-CoV-2 reinfection, versus intravascular lymphoma. After the treatment of intravenous immunoglobulin and methylprednisolone, her symptoms significantly improved. The second follow-up MRI two weeks later detected a new unenhanced lesion in the left temporal lobe. A brain biopsy was performed and IVLBCL was diagnosed. We reviewed the brain MRI findings of IVLBCL in the literature with the assistance of ChatGPT. Although less specific, the imaging features including "high signal lesions on DWI, meningeal thickening and enhancement, and masslike lesions" highly suggested the possibility of IVLBCL. The biopsy should be planned after imaging progression. The association between IVLBCL and SARS-CoV-2 reinfection is undefined. [ABSTRACT FROM AUTHOR]

Accurate measurement of the vibrotactile acuities of the human torso is the key to designing effective torso-worn vibrotactile displays for healthcare applications such as navigation aids for visually impaired persons. Although efforts have been made to measure vibrotactile acuities, there remains a lack of systematic studies addressing the spatial, temporal, and intensity-related aspects of vibrotactile sensitivity on the human torso. In this work, a torso-worn vibrotactile belt consisting of two crossed coin motor arrays was designed and a psychophysical study was carried out to measure the spatial, temporal, and intensity-related vibrotactile acuities of a set of human subjects wearing the designed belt. The objective parameters of vibrational intensity and the timing latency of the coin motor were also determined before measuring the vibrotactile acuities. The experimental results indicated that the tested coin motor was able to generate a median number of five and six available just-noticeable differences in intensity and duration, respectively. Among the four parameters of vibrational intensity, the perceived intensity was the most relevant to vibrational displacement. The spatial acuities measured as the degree of two-point spatial thresholds (TPTs) showed less individual difference than the distance TPTs. The results from the current work provide valuable guidance for the design of a comfortable torso-worn vibrotactile display using coin motors. [ABSTRACT FROM AUTHOR]

DBT reconstructs high‐resolution tomographic images through multi‐angle scanning. We aimed at investigating the diagnostic value of DBT in breast microcalcifications of Asian women. The clinical characteristics and diagnostic accuracy of FFDM and DBT in 70 breast cancer patients were compared. 52 malignant lesions and 24 benign lesions were found in 76 breast microcalcifications. FFDM presented with high sensitivity and low specificity of 94.2% and 45.8%, while DBT presented with high sensitivity and medium specificity of 96.1% and 62.5%. The positive predictive value, negative predictive value, and diagnostic coincidence rate of DBT were higher than those of FFDM (84.7%, 88.2%, 85.5% vs. 79.0%, 78.5%, 78.9%, respectively). The AUC of DBT was significantly higher than that of FFDM (Z = 2.322, P = 0.020), at 0.700 ± 0.055 [0.584‐0.800] and 0.793 ± 0.052 [0.685‐0.878], respectively. Thus, we concluded that DBT improves the diagnostic accuracy and detection rate of microcalcifications in Asian women. [ABSTRACT FROM AUTHOR]

Background There are few studies about the Liver Imaging Reporting and Data System (LI-RADS), which was developed with the purpose of standardizing the interpretation and reporting of liver imaging examinations in patients at risk for hepatocellular carcinoma (HCC). Purpose To evaluate the diagnostic accuracy of HCC diagnosis using LI-RADS. Material and Methods The computed tomography (CT), magnetic resonance imaging (MRI), and clinical data of 297 lesions in 249 patients between June 2012 and August 2013 were retrospectively analyzed. Using LI-RADS 2014, two radiologists evaluated the lesions and a LI-RADS category was retrospectively assigned to each nodule. Results The final diagnoses of 297 nodules in 249 patients consisted of 191 malignant and 106 benign lesions. Out of 44 LI-RADS category 1 lesions, none were HCCs. However, 2/25 category 2 lesions, 3/35 category 3 lesions, 16/25 category 4 lesions, 151/156 category 5 lesions, and 3/12 category LRM/OM (probable malignancy, not specific for HCC/other malignancy) lesions were HCCs. The Kappa value was 0.44 (95% confidence interval [CI] = 0.39-0.49) between two observers during LI-RADS grading. Conclusion The negative predictive value of LI-RADS category 1 was 100%. In addition, a relevant proportion of lesions categorized as category 2 or 3, or even as other malignancies, were HCCs. LI-RADS category 5 had a high specificity for HCC. LI-RADS was not able to give a differential diagnosis for the false-positive lesions of LI-RADS category 5. [ABSTRACT FROM AUTHOR]

While current guidelines recommend R2* method as the first-line method for liver iron concentration (LIC) measurement, its diagnostic accuracy is debatable. A prior meta-analysis suggested limited accuracy of R2* method for identifying patients with iron overload. However, substantial advances in R2* method over the past decade may have improved its diagnostic performance. The purpose of this study is to explore the accuracy of the R2* method in identifying patients at clinically relevant LIC thresholds (1.8, 3.2, 7.0, and 15.0 mg/g). This is a meta-analysis. On February 16, 2024, databases including PubMed, Medline, Embase, Web of Science, and the Cochrane Library were searched for studies using the R2* method to quantify LIC. R2* values were derived from gradient echo sequence, with LIC from the FerriScan® (R2) or biopsy as reference standard. The true positive, false positive, true negative, and false negative at each LIC threshold (1.8, 3.2, 7.0, and 15.0 mg/g) were extracted from each study by two reviewers. Summary receiver operating characteristic (SROC) curves were generated using the hierarchical SROC (HSROC) model. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Twenty-six studies with 1687 patients were included. In identifying patients at each LIC threshold (1.8, 3.2, 7.0, and 15.0 mg/g), the area under the SROC curves (AUCs) were 0.96 or higher, with pooled sensitivities of 0.95 or higher. Pooled specificities were 0.93 or higher; however, studies using biopsy as a reference showed a wide range 95% confidence interval (CI) (0.51-0.99) for identifying patients at the 1.8 mg/g threshold. The R2* method accurately identified patients at different clinically relevant LIC thresholds (1.8, 3.2, 7.0, and 15.0 mg/g). However, when biopsy is used as a reference, the method may be unstable for the 1.8 mg/g threshold (95% CI for pooled specificity, 0.51-0.99). LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2., (© 2025 International Society for Magnetic Resonance in Medicine.)

Objective: To innvestigate the rehabilitation effects of repetitive transcranial magnetic stimulation (rTMS) combined with cognitive training on cognitive impairment in patients with traumatic brain injury (TBI) by using multimodal magnetic resonance imaging., Methods: Clinical data of 166 patients with cognitive impairment after TBI were retrospectively analyzed. The patients were assigned into an observation group and a control group according to different treatment methods, with 83 cases in each group. The observation group was given rTMS + cognitive training, and the control group was given cognitive training only. The changes in GCS score, the Cho/Cr, Cho/NAA and NAA/Cr ratios examined by MRSI, the score of cognitive impairment, the grading of cognitive impairment, and the changes in modified Barthel index were observed and compared between the two groups., Results: The GCS score, and the ratios of Cho/Cr, Cho/NAA and NAA/Cr after treatment were better than those before treatment in both groups and were lower in the observation group compared with the control group (all P<0.05). The score and grading of cognitive impairment as well as modified Barthel index after treatment were all significantly better in the observation group than in the control group (all P<0.05)., Conclusion: rTMS can improve the rehabilitation effect on cognitive impairment in patients after TBI and is recommended for clinical use., Competing Interests: None., (AJTR Copyright © 2021.)