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Objective: To investigate the relationship between vestibular aqueduct (VA) morphology and Meniere's disease (MD) using ultrahigh‐resolution computed tomography (U‐HRCT). Methods: Retrospective data were collected from 34 patients (40 ears) diagnosed with MD in our hospital who underwent temporal bone U‐HRCT with isotropic 0.05‐mm resolution, magnetic resonance with gadolinium‐enhanced, and pure‐tone audiometry; 34 age‐ and sex‐matched controls (68 ears) who underwent U‐HRCT were also included. VA patency was qualitatively classified as locally not shown (grade 1), locally faintly shown (grade 2), or clearly shown throughout (grade 3). The width of the outer orifice and VA length and angle were quantitatively measured. Differences in VA morphology between the MD and control groups were analyzed. The correlations between VA morphology and the degrees of hearing loss and endolymphatic hydrops (EH) were also analyzed. Results: VA was classified as grades 1–3 in 11, 17, and 12 ears in the MD group and 5, 26, and 37 ears in the control group, respectively. The patency differed significantly between the groups (p < 0.01). The width of the outer orifice and length of VA were significantly smaller in the MD group than those in the control group (p < 0.05). Both VA patency and length were correlated with the degree of EH in the cochlea and the vestibule (p < 0.05). No difference was found between VA morphology and the degree of hearing loss (p > 0.05). Conclusion: The morphological characteristics of VA were found to be associated with the occurrence of MD and the degree of EH. Level of Evidence: 4 Laryngoscope, 134:3349–3354, 2024 [ABSTRACT FROM AUTHOR]

The aim of this study was to systematically investigate structural and functional alterations in amygdala subregions using multimodal magnetic resonance imaging (MRI) in patients with tinnitus with or without affective dysfunction. Sixty patients with persistent tinnitus and 40 healthy controls (HCs) were recruited. Based on a questionnaire assessment, 26 and 34 patients were categorized into the tinnitus patients with affective dysfunction (TPAD) and tinnitus patients without affective dysfunction (TPWAD) groups, respectively. MRI‐based measurements of gray matter volume, fractional anisotropy (FA), fractional amplitude of low‐frequency fluctuations (fALFF), regional homogeneity (ReHo), degree centrality (DC), and functional connectivity (FC) were conducted within 14 amygdala subregions for intergroup comparisons. Associations between the MRI properties and clinical characteristics were estimated via partial correlation analyses. Compared with that of the HCs, the TPAD and TPWAD groups exhibited significant structural and functional changes, including white matter integrity (WMI), fALFF, ReHo, DC, and FC alterations, with more pronounced WMI changes in the TPAD group, predominantly within the left auxiliary basal or basomedial nucleus (AB/BM), right central nucleus, right lateral nuclei (dorsal portion), and left lateral nuclei (ventral portion containing basolateral portions). Moreover, the TPAD group exhibited decreased FC between the left AB/BM and left middle occipital gyrus and right superior frontal gyrus (SFG), left basal nucleus and right SFG, and right lateral nuclei (intermediate portion) and right SFG. In combination, these amygdalar alterations exhibited a sensitivity of 65.4% and specificity of 96.9% in predicting affective dysfunction in patients with tinnitus. Although similar structural and functional amygdala remodeling were observed in the TPAD and TPWAD groups, the changes were more pronounced in the TPAD group. These changes mainly involved alterations in functionality and white matter microstructure in various amygdala subregions; in combination, these changes could serve as an imaging‐based predictor of emotional disorders in patients with tinnitus. [ABSTRACT FROM AUTHOR]

Accurate simulation of evapotranspiration (ET) is essential to enhance efficient irrigation management in the maize field. Here, we evaluated the performance of four mathematical models for estimating the ET of maize. The four models based on surface resistance calculate ET from different vapor sources, which are Penman‐Monteith (PM) through the "big leaf" model, the Shuttleworth‐Wallace (SW) model for distinguishing between soil and canopy, the clumping (C) model for distinguishing between canopy, soils under the canopy and bare soil, and the seasonal clumping (Cj) model for dividing ET into transpiration of sunlit leaves and shaded leaves, evaporation of bare soil surface, sunlit soil surface of canopy gap fraction, and canopy shaded soil surfaces. The models were calibrated by ET measured from a weighing lysimeter, transpiration by the sap flux method, and soil evaporation by micro‐lysimeters in 2014, 2015, and 2017. Results showed that the measured daily transpiration was 3.32 mm/day during the full‐grown stage of maize, and the mean measured daily soil evaporation was 1.46 mm/day. The performance of the sap flow for transpiration plus micro‐lysimeter for soil evaporation method was consistent with the large‐weighted lysimeter method in measuring daily ET. For simulating versus measuring hourly transpiration, the Cj model performed better than the C model with a slope of 0.94, determination coefficient (R2) of 0.85, mean absolute error (MAE) of 0.08 mm/h, and modified agreement index (d) of 0.81. In simulating daily soil evaporation, the Cj model also had a higher slope and less MAE than the C and SW models. Nevertheless, the Cj model yielded increased slope and d and decreased MAE between simulated and measured daily ET. The most sensitive environmental factor in the Cj model is temperature. With a 50% increase in temperature, ET, transpiration, and evaporation increase by 45%, 36%, and 69%, respectively. In summary, the Cj model improved the accuracy for hourly and daily ET of maize and helped separate plant transpiration and soil evaporation, thus giving an available approach for precision irrigation in water management of maize planting systems. [ABSTRACT FROM AUTHOR]

Aims: This study systematically investigated structural and functional alterations in the thalamus and its subregions using multimodal magnetic resonance imaging (MRI) and examined its clinical relevance in tinnitus patients with different outcomes after sound therapy (narrowband noise). Methods: In total, 60 patients with persistent tinnitus and 57 healthy controls (HCs) were recruited. Based on treatment efficacy, 28 patients were categorized into the effective group and 32 into the ineffective group. Five MRI measurements of the thalamus and its seven subregions, including gray matter volume, fractional anisotropy, fractional amplitude of low‐frequency fluctuation, and functional connectivity (FC), were obtained for each participant and compared between the groups. Results: Patients in both the groups exhibited widespread functional and diffusion abnormalities in the whole thalamus and several subregions, with more obvious changes observed in the effective group. All tinnitus patients had abnormal FC compared with the HCs; FC differences between the two patient groups were only observed in the striatal network, auditory‐related cortex, and the core area of the limbic system. We combined the multimodal quantitative thalamic alterations and used it as an imaging indicator to evaluate prognosis before sound therapy and achieved a sensitivity of 71.9% and a specificity of 85.7%. Conclusion: Similar patterns of thalamic alterations were identified in tinnitus patients with different outcomes, with more obvious changes observed in the effective group. Our findings support the tinnitus generation hypothesis of frontostriatal gating system dysfunction. A combination of multimodal quantitative thalamic properties may be used as indicators to predict tinnitus prognosis before sound therapy. [ABSTRACT FROM AUTHOR]

Objective: Although studies have demonstrated the involvement of the nucleus accumbens (NAc) in the neurobiology of eating disorders, its alterations in bulimia nervosa (BN) remain largely unknown. This study investigated the structural and functional properties of NAc in patients with BN. Method: Based on the resting‐state functional MRI and high‐resolution anatomical T1‐weighted imaging data acquired from 43 right‐handed BN patients and 40 sex‐, age‐ and education‐matched right‐handed healthy controls (HCs), the group differences in gray matter volume (GMV) and fractional amplitude of low‐frequency fluctuation (fALFF) in slow‐4 and ‐5 bands and functional connectivity (FC) of NAc subregions (core and shell) were compared. The relationships between MRI and clinical data were explored in the BN group. Results: Compared with HCs, BN patients showed preserved GMV, decreased fALFF in slow‐5 band of the left NAc core and shell, decreased FC between left NAc core and right caudate, and increased FC between all NAc subregions and frontal regions, between all NAc subregions (except the right NAc core) and the supramarginal gyrus (SMG), and between right NAc shell and left middle temporal gyrus. FC between the NAc and SMG was correlated with emotional eating behaviors. Discussion: Our study revealed preserved GMV, local neuronal activity reduction and functional network reorganization of the NAc in BN. The functional network reorganization of the NAc mainly occurred in the frontal cortex and was correlated with emotional eating behavior. These findings may provide novel insights into the BN using NAc as an entry point. Public significance: Although studies have demonstrated the involvement of the nucleus accumbens (NAc) in the neurobiology of eating disorders, its alterations in bulimia nervosa (BN) remain largely unknown. We used a multimodal MRI technique to systematically investigate structural and functional alterations in NAc subregions of BN patients and explored the associations between such alterations and maladaptive eating behaviors, hoping to provide novel insights into BN. [ABSTRACT FROM AUTHOR]

Background: The significance of liver metastasis (LM) in increasing the risk of death for postoperative colorectal cancer (CRC) patients necessitates innovative approaches to predict LM. Aim: Our study presents a novel and significant contribution by developing an interpretable fusion model that effectively integrates both free‐text medical record data and structured laboratory data to predict LM in postoperative CRC patients. Methods: We used a robust dataset of 1463 patients and leveraged state‐of‐the‐art natural language processing (NLP) and machine learning techniques to construct a two‐layer fusion framework that demonstrates superior predictive performance compared to single modal models. Our innovative two‐tier algorithm fuses the results from different data modalities, achieving balanced prediction results on test data and significantly enhancing the predictive ability of the model. To increase interpretability, we employed Shapley additive explanations to elucidate the contributions of free‐text clinical data and structured clinical data to the final model. Furthermore, we translated our findings into practical clinical applications by creating a novel NLP score‐based nomogram using the top 13 valid predictors identified in our study. Results: The proposed fusion models demonstrated superior predictive performance with an accuracy of 80.8%, precision of 80.3%, recall of 80.5%, and an F1 score of 80.8% in predicting LMs. Conclusion: This fusion model represents a notable advancement in predicting LMs for postoperative CRC patients, offering the potential to enhance patient outcomes and support clinical decision‐making. [ABSTRACT FROM AUTHOR]

Accumulating evidence supports the hypothesis that white matter (WM) abnormalities are involved in the pathophysiology of bulimia nervosa (BN); however, findings from in vivo neuroimaging studies have been inconsistent. We aimed to investigate the possible brain WM alterations, including WM volume and microstructure, in patients with BN. We recruited 43 BN patients and 31 healthy controls (HCs). All participants underwent structural and diffusion tensor imaging. Differences in WM volume and microstructure were evaluated using voxel‐based morphometry, tract‐based spatial statistics, and automated fibre quantification analysis. Compared with HCs, BN patients showed significantly decreased fractional anisotropy in the middle part of the corpus callosum (nodes 31–32) and increased mean diffusivity in the right cranial nerve V (CN V) (nodes 27–33 and nodes 55–88) and vertical occipital fasciculus (VOF) (nodes 58–85). Moreover, we found decreased axial diffusivity in the right inferior fronto‐occipital fasciculus (node 67) and increased radial diffusivity in the CN V (nodes 22–34 and nodes 52–89) and left VOF (nodes 60–66 and nodes 81–85). Meanwhile, WM microstructural changes were correlated with patients' clinical manifestations. We did not find any significant differences in WM volume and the main WM fibre bundle properties between BN patients and HCs. Taken together, these findings provide that BN shows significant brain WM reorganization, but primarily in microstructure (part of WM fibre bundle), which is not sufficient to cause changes in WM volume. The automated fibre quantification analysis could be more sensitive to detect the subtle pathological changes in a point or segment of the WM fibre bundle. [ABSTRACT FROM AUTHOR]

Accurate vestibule segmentation for CT images is of great significance for the clinical diagnosis of congenital ear malformations and cochlear implant. However, it is still a challenging task due to extremely small size and irregular shape of vestibule. Here, a vestibule segmentation network for CT images is proposed under the basic encoder‐decoder framework. Firstly, a residual block based on channel attention mechanism, named Res‐CA block, is designed to guide the network to enhance the important features for the segmentation tasks while suppressing the irrelevant ones. And then, a global context‐aware pyramid feature extraction (GCPFE) module is proposed to capture multi‐receptive‐field global context information. Finally, active contour with elastic (ACE) loss function is adopted to guide network learning more detailed information of the boundary. Furthermore, deep supervision (DS) mechanism is employed to locate the boundaries finely, improving the robustness of the network. The experiments are conducted on the self‐established VestibuleDataset and UHRCT‐Dataset, as well as publicly available retinal dataset, namely DRIVE, to comprehensively verify the robustness and generalization capability of the proposed segmentation network. The experimental results show that the proposed network can achieve a superior performance. [ABSTRACT FROM AUTHOR]

Purpose: To introduce a dual‐domain reconstruction network with V‐Net and K‐Net for accurate MR image reconstruction from undersampled k‐space data. Methods: Most state‐of‐the‐art reconstruction methods apply U‐Net or cascaded U‐Nets in the image domain and/or k‐space domain. Nevertheless, these methods have the following problems: (1) directly applying U‐Net in the k‐space domain is not optimal for extracting features; (2) classical image‐domain–oriented U‐Net is heavyweighted and hence inefficient when cascaded many times to yield good reconstruction accuracy; (3) classical image‐domain–oriented U‐Net does not make full use of information of the encoder network for extracting features in the decoder network; and (4) existing methods are ineffective in simultaneously extracting and fusing features in the image domain and its dual k‐space domain. To tackle these problems, we present 3 different methods: (1) V‐Net, an image‐domain encoder–decoder subnetwork that is more lightweight for cascading and effective in fully utilizing features in the encoder for decoding; (2) K‐Net, a k‐space domain subnetwork that is more suitable for extracting hierarchical features in the k‐space domain, and (3) KV‐Net, a dual‐domain reconstruction network in which V‐Nets and K‐Nets are effectively combined and cascaded. Results: Extensive experimental results on the fastMRI dataset demonstrate that the proposed KV‐Net can reconstruct high‐quality images and outperform state‐of‐the‐art approaches with fewer parameters. Conclusions: To reconstruct images effectively and efficiently from incomplete k‐space data, we have presented a dual‐domain KV‐Net to combine K‐Nets and V‐Nets. The KV‐Net achieves better results with 9% and 5% parameters than comparable methods (XPD‐Net and i‐RIM). [ABSTRACT FROM AUTHOR]

Purpose: Due to the different posture of the subject and settings of CT scanners, the CT images of the human temporal bone should be geometrically aligned with multiplanar reconstruction to ensure the symmetry of the bilateral anatomical structure. Manual alignment is a time‐consuming task for radiologists and an important preprocessing step for further computer‐aided CT analysis. We propose a fully automatic alignment algorithm for temporal bone CT images via lateral semicircular canals (LSCs) segmentation. Methods: The LSCs are segmented with our proposed multifeature fusion network as anchors at first. Then, we define a standard 3D coordinate system and propose an alignment procedure. Results: The experimental results show that our LSC segmentation network achieved a higher segmentation accuracy. The acceptable rate is achieved 85% over 910 raw temporal bone CT sequences. The alignment speed is reduced from 10 min by manual to 60s. Conclusions: Aiming at the problem of bilateral asymmetry in the raw temporal bone CT images, we propose an automatic geometric alignment method. Our proposed method can help to perform alignment of temporal bone CT images efficiently. [ABSTRACT FROM AUTHOR]

Topological properties, which serve as the core of the neural network, and their couplings can reflect different therapeutic effects in tinnitus patients. We hypothesized that tinnitus patients with different outcomes after sound therapy (narrowband noise) would have distinct brain network topological alterations. Diffusion tensor imaging and resting‐state functional magnetic resonance imaging (fMRI) were prospectively performed in 60 patients with idiopathic tinnitus and 57 healthy controls (HCs). Graph‐theoretical network analyses of structural connectivity (SC), functional connectivity (FC), and SC and FC coupling were performed. Associations between clinical performance and graph‐theoretical features were also analyzed. Treatment was effective (effective group; EG) in 28 patients and ineffective (ineffective group; IG) in 32 patients. For FC, the patients in the EG showed higher local efficiency than patients in the IG. For SC, patients in both the EG and IG displayed lower normalized characteristic path length, characteristic path length, and global efficiency than the HCs. More importantly, patients in the IG had higher coupling than the HCs, whereas there was no difference in coupling between patients in the EG and HCs. Additionally, there were significant associations between the SC features and clinical performance in patients in the EG. Our findings demonstrate that tinnitus patients exhibited significant brain network topological alterations, especially in the structural brain network. More importantly, patients who demonstrated different curative effects showed distinct SC‐FC topological coupling properties. SC‐FC coupling could be an indicator that could be used to predict prognoses in patients with idiopathic tinnitus before sound therapy. [ABSTRACT FROM AUTHOR]

Background: MRI is the most effective diagnostic tool of osteonecrosis of the femoral head (ONFH), especially for early diagnosis, but its detection of subchondral or cortical fractures is less accurate than CT. Therefore, it is difficult to accurately stage ONFH in the peri‐collapse period by MRI. Purpose To improve the accuracy of MR for distinguishing between Association Research Circulation Osseous (ARCO) stages 2 and 3A in ONFH. Study Type: Retrospective. Subjects: One hundred and fifty five cases of ARCO stage 2/3A of ONFH underwent MR examinations, M/F = 72/83. CT was used as reference standard for collapse, which was decided by an orthopedist and a radiologist in consultation. Field Strength/Sequence: 3 T/axial and coronal T1‐weighted Turbo Spin Echo (T1W TSE) sequence, axial T2‐weighted fat‐saturated (T2W FS) TSE sequence, and coronal proton density‐weighted imaging (PDWI)‐FS‐Dixon fat/water image. Assessment Five potential MR signs (the maximum width of the necrotic‐viable interface, bone marrow edema (BME), irregular articular surface of the femoral head, T2 heterogeneous high signal, and the absence of a necrotic‐viable interface with the morphology of closed loop) were evaluated blindly by five radiologists independently and the total scores of different combinations of MR signs were calculated. Statistical Tests: Mann–Whitney U test and Chi‐square test were used to evaluate age, gender, and MR signs differences between the two groups. ROC curve was used to access the distinguishing value of MR signs. The consistency of the five radiologists was analyzed by intraclass correlation coefficient. Results: The area under the curve of the combined MR signs 2 for distinguishing between ARCO stages 2 and 3A was the greatest (0.967), sensitivity and specificity were 100.00% and 88.71% respectively, and greater than 1 was the threshold. Data Conclusion: Combined MR signs 2 has great values in distinguishing between ARCO stages 2 and 3A in ONFH, thus helping clinical therapy. Level of Evidence: 4 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Patients with pulsatile tinnitus (PT) have unstable treatment effects after resurfacing surgery. Flow‐diverting stents (FDS) are proposed as a potential method for the treatment of PT, but the therapeutic effect is not clear. This study aimed to investigate the efficacy of FDS in the treatment of patients with PT induced by sigmoid sinus diverticulum (SSD) and sigmoid sinus wall dehiscence (SSWD). In addition, we aimed to explore the treatment mechanism of PT. Transient‐state multiphysics coupling numerical simulation method based on computed tomography angiography of five patients was used to clarify the biomechanical and acoustic states before and after FDS placement. FDS was placed to prevent the blood flow from impacting the vessel wall in the SSD and SSWD areas. Low blood flow velocity (<0.0391 m/s), high relative residence time (>10 Pa−1), and low wall shear stress of SSD might lead to thrombosis after FDS placement. The average pressure on the SSWD area of each patient decreased by 13.77%, 18.82%, 29.23%, 19.03%, and 11.20%. The average displacement of the vessel wall on the SSWD area showed acute pulsation and decreased by 15.29%, 14.64%, 30.22%, 41.03%, and 21.28%. The average sound pressure level at the tympanum decreased by 14.01%, 9.33%, 17.66%, 18.88%, and 25.18%, respectively. In brief, FDS was placed to avoid blood flow impacting vessels and reduce the vibration of vessels in the short term, thereby attenuating the degree of PT. The long‐term prognosis was that the SSWD area was blocked after SSD thrombosis. Therefore, FDS might be an effective method for the treatment of PT induced by SSD and SSWD. This study would provide a theoretical basis for the treatment of PT and an exploration of FDS design in the treatment of PT. [ABSTRACT FROM AUTHOR]

Previous studies demonstrated that brain morphological differences and distinct patterns of neural activation exist in tinnitus patients with different prognoses after sound therapy. This study aimed to explore possible differences in intrinsic network‐level functional connectivity (FC) in patients with different outcomes after sound therapy (narrow band noise). We examined intrinsic FC using resting‐state functional magnetic resonance imaging in 78 idiopathic tinnitus patients (including 35 effectively treated and 43 ineffectively treated) and 52 healthy controls (HCs) via independent component analysis. We also investigated the associations between the differences in FC and clinical variables. Analyses revealed significantly altered intranetwork connectivity in the auditory network (AUN) and some nonauditory‐related networks in the EG/IG patients compared to HCs; compared with EG patients, IG patients showed decreased intranetwork connectivity in the anterior default mode network (aDMN) and AUN. Meanwhile, robust differences were also evident in internetwork connectivity between some nonauditory‐related networks (salience network and executive control network; posterior default mode network and dorsal attention network) in the EG relative to IG patients. We combined intranetwork connectivity in the aDMN and AUN as an imaging indicator to evaluate patient outcomes and screen patients before treatment; this approach reached a sensitivity of 94.3% and a specificity of 76.7%. Our study suggests that tinnitus patients with different outcomes show distinct network‐level functional reorganization patterns. Intranetwork connectivity in the aDMN and AUN may be indicators that can be used to predict prognoses in patients with idiopathic tinnitus and screen patients before sound therapy. [ABSTRACT FROM AUTHOR]

Background: Metabolic syndrome increases the risk of chronic diseases such as cardiovascular disease and diabetes. Metabolic syndrome also has an impact on bone mineral density. However, the relationship between metabolic syndrome and bone marrow fat is unclear.Purpose: To determine factors associated with bone marrow fat concentration in subjects with and without metabolic syndrome.Study Type: Retrospective.Population: One hundred and one women with metabolic syndrome (31.0 years ±5.1) and 96 female living liver transplant donors (32.0 years ±3.7). Our institutional review board approved the study. Each subject signed written informed consent.Field Strength/sequence: 3.0 T MRI system and a commercially available chemical shift-encoded 3D sequence (Iterative Decomposition of water and fat with Echo asymmetry and Least Square Estimation).Assessment: Proton density fat fraction (PDFF) in liver, vertebral body, and paraspinal muscle (erector spinae) were measured from a single acquisition by a 15-year-experience orthopedic radiologist. The factors associated with PDFF were acquired.Statistical Tests: The analysis of covariance test, after adjustment for body mass index and age, was used to analyze the differences between metabolic syndrome and non-metabolic syndrome groups. A stepwise multiple regression analysis was used to determine which variables were independently associated with PDFF.Results: Mean vertebral PDFF and alanine aminotransferase (ALT) were significantly lower in donors than subjects with metabolic syndrome (both P < 0.05). Serum vitamin D concentration, ferritin, and high-density lipoprotein (HDL) cholesterol were significantly higher in donors than subjects with metabolic syndrome (all P < 0.05). Multiple regression analysis revealed antidiabetic medicine, higher serum vitamin D concentration, lower waist circumference, lower ferritin, lower HDL, absence of metabolic syndrome, and lower ALT were significantly associated with lower vertebral PDFF (all P < 0.05).Data Conclusion: Multiple factors affect bone marrow fat concentration in subjects with metabolic syndrome. Serum vitamin D concentration and antidiabetic medicine are associated with low bone marrow fat, whereas waist circumference, serum ferritin, metabolic syndrome, imbalanced lipid metabolism, and abnormal liver function are associated with high bone marrow fat.Level Of Evidence Level: 3 TECHNICAL EFFICACY STAGE: 1. [ABSTRACT FROM AUTHOR]

The effects of morphologic abnormalities, including sigmoid sinus wall dehiscence (SSWD), transverse sinus stenosis (TSS), and sigmoid sinus diverticulum (SSD), on hemodynamics in venous pulsatile tinnitus (PT) patients have not been established. The aim of this study was to evaluate the effects of SSWD, TSS, and SSD on the hemodynamics of transverse-sigmoid sinus in venous PT patients. This was a prospective study with 44 venous PT patients and 12 healthy controls. A 3 T/four-dimensional (4D) flow magnetic resonance imaging with fast field echo was used. Computed tomography arteriography/venography was used to assess ipsilateral SSWD, TSS, and SSD. Maximum velocity (Vmax ), average velocity (Vavg ), and average flow (Flowavg ) were measured. Blood flow patterns were independently assessed by three neuroradiologists. One-way analysis of variance or Kruskal-Wallis test was also used. On the symptomatic side, all patients had SSWD, 33 patients had TSS, and 22 patients had SSD. Compared with healthy controls, patients with TSS, without TSS, with SSD, and without SSD all showed higher Vmax (all p < 0.050), Vavg (all p < 0.050), and Flowavg (all p < 0.050). Patients with TSS showed higher Vmax (p < 0.050) and Vavg (p < 0.050) than those without TSS, and no significant difference in Flowavg was found between the two groups (p = 0.408). No significant differences in Vmax , Vavg , and Flowavg were found between patients with and without SSD (all p = 1.000). Jet-like flow in the stenosis and downstream of the stenosis was observed in all patients with TSS. Vortex in SSD was observed in 15 patients with SSD (68%). High blood velocity and flow may be characteristic markers of venous PT. SSWD may be a necessary condition for venous PT. TSS may further increase the blood velocity and form a jet-like flow. SSD may be related to vortex formation but had no significant effect on blood velocity and flow. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 3. [ABSTRACT FROM AUTHOR]

Background: Distinguishing between the two broad categories of diabetic retinopathy (DR), nonproliferative DR (NPDR) and proliferative DR (PDR), is significant, as the therapeutic strategies for each are completely different. Purpose: To characterize the ocular blood flow (OBF) of DR patients and evaluate the potential utility of OBF values in categorizing DR. Study Type: Prospective. Subjects: A total of 41 DR patients (82 eyes) were recruited in our study. Group 1 comprised 48 eyes with NPDR, and Group 2 comprised 34 eyes with PDR. Field Strength/Sequence: 3D pseudocontinuous arterial spin labeling (3D‐pcASL) with two postlabeling delays (PLDs) was acquired at 3.0T MR. Assessment: OBF values were independently obtained by two doctors from the OBF map. Statistical Tests: OBF values and clinical characteristics were compared between the groups using two‐sample t‐tests and chi‐square tests. Receiver operating characteristic (ROC) curves were obtained, and the area under the curve (AUC) was calculated. The consistency of OBF values reported by the two doctors was evaluated using the intraclass correlation coefficient (ICC). Results: OBF values at PLDs of 1.5 seconds and 2.5 seconds were significantly lower in Group 2 than in Group 1 (P < 0.05 for both PLDs). The OBF values of Group 2 showed a greater increase than those of Group 1 from PLD 1.5 to 2.5 seconds. The AUC of OBF at the 1.5 seconds PLD was 0.90, with a cutoff of 7.73 mL/min/100 g, and the AUC of the OBF at the 2.5 seconds PLD was 0.75, with a cutoff of 8.44 mL/min/100 g. The ICC between the two observers was 0.844 for the OBF at 1.5 seconds PLD and 0.872 for the OBF at 2.5 seconds PLD. Data Conclusion: PDR can be differentiated from NPDR by the value of OBF as measured by 3D‐pcASL. Level of Evidence: 1 Technical Efficacy Stage: 1 [ABSTRACT FROM AUTHOR]

This study aimed to explore brain structural and white matter microstructural reorganization in the early stage of tinnitus and identify brain alterations that contribute to its relief after 6 months of sound therapy. We studied 64 patients with idiopathic tinnitus, including 29 patients who were categorized into an effective group (EG) and 35 who were categorized into an ineffective group (IG) according to the 6‐month follow‐up improvement of the Tinnitus Handicap Inventory score, along with 63 healthy controls (HCs). All participants underwent structural and diffusion tensor imaging scanning on a 3‐T magnetic resonance system. Differences in brain gray/white matter volume and white matter microstructure were evaluated using voxel‐based morphometry analysis and tract‐based spatial statistics among the three groups. Associations between brain reorganization and the improvement of tinnitus symptoms were also investigated. Compared with EG patients, IG patients experienced a significant gray matter volume decrease in the right middle frontal gyrus (MFG)/right precentral gyrus (PreCG). Meanwhile, both EG and IG patients showed significant changes (decrease or increase) in brain white matter integrity in the auditory‐related or nonauditory‐related white matter fiber tracts compared with HCs, while EG patients showed decreased axial diffusivity in the bilateral middle cerebellar peduncle (MCP) compared with IG patients. We combined the gray matter change of the MFG/PreCG and the white matter integrity of the bilateral MCP as an imaging indicator to evaluate the patient's prognosis and screen patients before treatment; this approach reached a sensitivity of 77.1% and a specificity of 82.8%. Our study suggests that there was a close relationship between brain reorganization and tinnitus improvement. The right MFG/PreCG and bilateral MCP may be indicators that can be used to predict prognoses in patients with idiopathic tinnitus and may be used to screen patients before sound therapy. These findings may provide new useful information that can lead to a better understanding of the tinnitus mechanism. [ABSTRACT FROM AUTHOR]

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Background: Accurate preoperative assessment of the pathological grade of hepatocellular carcinoma (HCC) could greatly benefit prognostic predictions.Purpose: To assess and compare the diagnostic accuracy of the apparent diffusion coefficient (ADC) and tissue diffusivity (D) for the noninvasive pathological grading of HCC.Study Type: Meta-analysis.Data Sources: PubMed/Medline, EMBASE, the Web of Science, and the Cochrane Library were searched to find related original articles published up to May 30, 2019.Field Strength/sequence: Diffusion-weighted imaging (DWI) and/or intravoxel incoherent motion (IVIM) were performed with a 1.5T or 3.0T scanner.Assessment: The Quality Assessment of Diagnostic Accuracy Studies 2 tool was used to assess the methodologic quality.Statistical Tests: The bivariate random-effects model was used to obtain the pooled sensitivity and specificity, and the area under summary receiver operating characteristic curve (AUROC) was obtained. Subgroup analyses were performed.Results: A total of 16 original articles (1428 HCCs) were included. Most studies had a low to unclear risk of bias and minimal concerns regarding applicability. For the discrimination of well-differentiated HCCs, the pooled sensitivity and specificity of the ADC value were 85% and 92%, respectively. For the discrimination of poorly differentiated HCCs, the pooled sensitivity and specificity of the ADC value and D were 84% and 80%, and 92% and 77%, respectively. The summary AUROC of D (0.94) was significantly higher than that of ADC (0.89) (z = -2.718, P = 0.007). The subgroup analyses identified three covariates including size, number of included lesions in the studies, and blindness to the reference standard as possible sources of heterogeneity.Data Conclusion: This meta-analysis showed that the ADC and D values had a high to excellent accuracy for the noninvasive pathological grading of HCCs and that the D value was superior to the ADC value for discriminating poorly differentiated HCCs.Level Of Evidence: 3 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:1581-1593. [ABSTRACT FROM AUTHOR]

Introduction Many studies have reported brain volume changes in smokers. However, the volume differences of grey matter (GM) and white matter (WM) in young and middle-aged male smokers with different lifetime tobacco consumption (pack-years) remain uncertain. Objectives To examine the brain volume change, especially whether more pack-years smoking would be associated with smaller gray matter and white matter volume in young and middle-aged male smokers. Methods We used a 3T MR scanner and performed Diffeomorphic anatomical registration through exponentiated lie algebra (DARTEL)-based voxel-based morphometry on 53 long-term male smokers (30.72 ± 4.19 years) and 53 male healthy non-smokers (30.83 ± 5.18 years). We separated smokers to light and heavy smokers by pack-years and compared brain volume between different smoker groups and non-smokers. And then we did analysis of covariance (ANCOVA) between smokers and non-smokers by setting pack-years as covariates. Results Light and heavy smokers all displayed smaller GM and WM volume than non-smokers and more obviously in heavy smokers. The main smaller areas in light and heavy smokers were superior temporal gyrus, insula, middle occipital gyrus, posterior cingulate, precuneus in GM and posterior cingulate, thalamus and midbrain in WM, in addition, we also observed more pack-years smoking was associated with some certain smaller GM and WM volumes by ANCOVA. Conclusion Young and middle-aged male smokers had many smaller brain areas than non-smokers. Some of these areas' volume had negative correlation with pack-years, while some had not. These may due to different pathophysiological role of smokings. [ABSTRACT FROM AUTHOR]

Purpose: To explore the potential of texture analysis based on apparent diffusion coefficient (ADC) maps, as a predictor of local invasion depth (stage pT1-2 versus pT3-4) and nodal status (pN0 versus pN1-2) of rectal cancer.Materials and Methods: Sixty-eight patients with rectal cancer underwent preoperative magnetic resonance (MR) imaging including diffusion weighted imaging (DWI) at a 3.0 Tesla system. Routine ADC variables (ADCmean , ADCmin , ADCmax ), histogram features (skewness, kurtosis) and gray level co-occurrence matrix features (entropy, contrast, correlation) were compared between pT1-2 and pT3-4 stages, between pN0 and pN1-2 stages.Results: Skewness, entropy, and contrast were significantly lower in patients with pT1-2 as compared to those with pT3-4 tumors (0.166 versus 0.476, P = 0.015; 3.212 versus 3.441 P = 0.004; 10.773 versus 13.596, P = 0.017). Furthermore, skewness and entropy were identified as independent predictors for extramural invasion of tumors (stage pT3-4). Significant differences were observed between pN0 and pN1-2 tumors with respect to ADCmean (1.152 versus 1.044, P = 0.029), ADCmax (1.692 versus 1.460, P = 0.006) and entropy (3.299 versus 3.486, P = 0.015). ADCmax. and entropy were independent predictors of positive nodal status.Conclusion: Texture analysis on ADC maps could provide valuable information in identifying locally advanced rectal cancer.Level Of Evidence: 3 J. MAGN. RESON. IMAGING 2017;45:1798-1808. [ABSTRACT FROM AUTHOR]

Purpose:The purpose of this study was to optimize intra-voxel incoherent motion (IVIM) measurement in diffusion-weighted imaging (DWI) of breast cancer by separating perfusion and diffusion effects through the determination of an optimal threshold b-value, thus benign and cancerous breast tissues can be accurately differentiated using IVIM-derived diffusion and perfusion parameters. Materials and Methods: Twenty-eight patients, with biopsy-confirmed breast cancers, were studied with a 3T MRI scanner, using T1-weighted dynamic contrast-enhanced MRI images, and diffusion-weighted images with nine b-values, ranging from 0 to 1000 s/mm2. IVIM-derived parameter maps for tissue diffusion coefficients D, perfusion fraction f, and pseudo-diffusion coefficients D* were computed using the segmented fitting method with optimized threshold b-value, and the sum of squared residuals (SSR) were calculated for IVIM-derived parameters in different breast lesions. Results: The IVIM analysis method developed in this work can separate perfusion and diffusion effects with the optimal threshold b-value of 300 s/mm2, and the results of diffusion and perfusion parameters from IVIM analysis can be used to differentiate pathological changes in breast tissues. It was found that the averages and standard deviations of the diffusion and perfusion parameters, D, f, D*, are the following, for malignant, benign and normal breast tissues respectively: D (0.813 ± 0.225 × 10-3 mm2/s, 1.437 ± 0.538 × 10-3 mm2/s, 1.838 ± 0.213 × 10-3 mm2/s), f (10.73 ± 3.44%, 7.86 ± 3.70%, 8.92 ± 3.72%), D* (15.23 ± 12.17×10-3 mm2/s, 12.02 ± 3.19 × 10-3 mm2/s, 12.03 ± 7.21 × 10-3 mm2/s). Conclusion: IVIM-derived diffusion and perfusion parameter maps depend highly on the choice of threshold b-value. Using the methodology developed in this work, and with the optimized threshold b-value, the diffusion and perfusion parameters of breast tissues can be accurately assessed, making IVIM MRI a technique of choice for differential diagnosis of breast cancer. [ABSTRACT FROM AUTHOR]

The article focuses on a study which synthesized organic/inorganic hybrids with silica contents from bisphenol-A and epichlorohydrin using γ-thiopropyl triethoxy silane (KH580). It cites the hypothesis for the functional silanol group of KH580. Results of the study showed that silicon dioxide content influenced the shear strength of epoxy resin-based composite. It also notes the influence of silicon dioxide content on composite toughness.