Three DW protocols (SPEN, SS-EPI, RESOLVE) were evaluated by breast radiologists and medical students using a semi-quantitative scoring system. Additionally, a breast-specific phantom, encompassing typical malignant and benign breast lesions, was used to measure the ADC values in each DWI protocol. The ADC values were also measured for malignant lesions. SPEN sequences demonstrated significantly higher conspicuity scores than conventional DWI. Moreover, RESOLVE exhibited significantly higher scores compared to both SPEN and conventional DWI.

　Accurate discrimination between muscle and non-muscle-invasive bladder cancer (MIBC and NMIBC, respectively) is essential for treatment planning and prognosis prediction. The present study investigated whether quantitative magnetic resonance imaging (MRI) parameters, including synthetic MRI (SyMRI), can enhance the diagnostic value of the Vesical Imaging Reporting and Data System (VI-RADS). Sixty-four patients (54 males, median age 73 years) with pathology confirmed MIBC or NMIBC were included. Bladder MRI, using VI-RADS scores and SyMRI, was performed before transurethral resection. Pretherapeutic quantitative parameters, including T1, T2, proton density from SyMRI, and apparent diffusion coefficient (ADC) values, were measured. Statistical analysis included the Cochran-Armitage trend and Wilcoxon rank-sum tests, and logistic regression models with receiver operating characteristic (ROC) analysis. VI-RADS scores were associated with the incidence of MIBC ( p<0.0001). Patients with MIBC exhibited significantly lower T1, T2, and ADC values (1451 ms, 106 ms, 0.88×10⁻³ mm²/s, respectively) than those with NMIBC (1644 ms, 124 ms, 1.46×10⁻³ mm²/s) (p<0.05 for all). ADC values had the highest area under the ROC curve (AUC, 0.93；cut-off, 1.22×10⁻³ mm²/s；sensitivity, 100％；specificity, 78％). Combining ADC values with VI-RADS scores improved MIBC prediction (AUC 0.98), although not significantly ( p＝0.084). For VI-RADS scores 2 and 3 (n＝44), a low ADC value (cut-off 1.22×10⁻³ mm²/s) prevented underdiagnosis of MIBC with high sensitivity (n＝6/6 [100％]). ADC analysis and VI-RADS were effective in distinguishing MIBC from NMIBC. Combining ADC values with VI-RADS scores demonstrated potential as an imaging marker for evaluation of MIBC.

　Multi-delay PCASL acquisition with a hybrid scheme that combines time-encoded and variable-TR schemes was developed. This hybrid scheme combines the advantages of a high signal-to-noise ratio (SNR) obtained using a time-encoded scheme with the timing flexibility of a variable-TR scheme. This study aimed to investigate the ability of a hybrid scheme for cerebral blood flow (CBF) and arterial transit time (ATT) quantification in patients with Moyamoya disease. A total of 13 patients with Moyamoya disease were included in the present study. The MRI protocol included a variable TR scheme with 12 delays (vTR12), a time-encoded scheme with seven delays (TEnc7), and a hybrid scheme with 4×3 delays (Hyb12). The temporal SNR (tSNR), CBF, and ATT were measured using a vascular atlas template. The tSNR of Hyb12 was significantly higher than those of vTR12 (P<0.0001) and TEnc7 (P<0.0001). The CBF of Hyb12 was significantly lower than that of vTR12 (P＝0.0186) and TEnc7 (P＝0.0005). The ATT of Hyb12 was significantly shorter than those of vTR12 (P<0.0001) and TEnc7 (P<0.0001). CBF measured with Hyb12 showed significant correlations and excellent agreement with those measured with vTR12 (r＝0.8269, ICC＝0.8966) and TEnc7 (r＝0.8586, ICC＝0.9585). The quantitative capability of CBF and ATT in the hybrid scheme was confirmed in the assessment of cerebral perfusion in Moyamoya disease.

Objective/Background

　Previous reports have suggested that breath-hold (BH) three-dimensional (3D) magnetic resonance cholangiopancreatography (MRCP) provides additional value with respiratory-gated 3D MRCP. Although these methods have been reported to suppress “respiratory artifacts,” the influence of gastrointestinal peristalsis around the target organs is not mentioned. On the other hand, the autonomic nervous system has been reported to affect gastrointestinal peristalsis. There are also reports that BH imaging influences venous blood flow through its involvement with the autonomic nervous system. We examined the effects of BH imaging on gastrointestinal peristalsis.

Methods

　Seven healthy volunteers provided informed consent for our study. Gastrointestinal peristalsis was measured using cine magnetic resonance imaging (MRI) with two-dimensional (2D) FIESTA. Cine MRI data were analyzed using the normalized interframe difference method in MATLAB, focusing on the duodenum and gastric body. Three respiratory patterns—free breathing (FB) with assumed respiratory gating, BH at maximum inspiration (Insp-BH), and BH at maximum expiration (Exp-BH)—were employed. Hemodynamic changes resulting from BH methods were evaluated using 2D phase contrast, targeting the inferior vena cava (IVC). The blood flow signal (BFS) was examined for all phases of each respiratory pattern. Statistical analysis used one-way ANOVA.

Results

　Peristaltic variation in the duodenum showed no significant differences among FB (2.03±0.86), Exp-BH (1.32±0.63), and Insp-BH (1.20±0.91). In the gastric body, no significant differences were observed between FB and Exp-BH or between Exp-BH and Insp-BH. However, a significant difference emerged between FB and Insp-BH (p<0.05). Regarding BFS, significant differences in IVC were noted between Exp-BH and Insp-BH, as well as between FB and Insp-BH (both p<0.01). Meanwhile, no significant difference was found between FB and Exp-BH.

Conclusions

　Our study suggests that Insp-BH reduces venous blood flow and suppresses the influence of peristaltic variation.

　This study employed deep learning techniques to enhance the image quality of low-field knee MRI, with the goal of aligning it with high-field standards and visualizing transformation effects via texture analysis. Through training on 3T data (51 individuals) and by validating on 0.4T data (25 individuals) with two distinct models (super-resolution and contrast generation), the results might reveal an enhancement in the image quality of low-field knee MRI.

　This study developed a method based on to subdivide the brain’s Triple Network, revealing balanced connectivity across subregions, and improving mild cognitive impairment (MCI) diagnosis. Subregional analysis yielded further understanding of brain network disruptions, suggesting its potential in improving cognitive disorder evaluation.

　Severe patients may ask for the scan to be aborted. We evaluated whether conspicuous artifacts could be reduced in the 2DFSE sequence when the scan was aborted using the iterative parallel reconstruction and acquired data. The conspicuous artifacts were diminished, even though all the data were not acquired.

　Highly sensitive ¹H/²³Na dual-tuned RF coils traditionally involve a number of decoupling components. Hence, it is difficult to fit them into the narrow bore of high-field NMR magnets. To overcome this, we explore inductively coupled RF coils that eliminate the need for decoupling components and enable efficient utilization of the narrow high-field spaces.