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Objectives: This study aimed to assess the diagnostic image quality and compare the knee cartilage segmentation results using a controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA)-accelerated 3D-dual echo steady-state (DESS) research package sequence in the knee., Materials and Methods: A total of 64 subjects underwent both two- and fourfold CAIPIRINHA-accelerated 3D-DESS and DESS without parallel acceleration technique of the knee on a 3.0 T system. Two musculoskeletal radiologists evaluated the images independently for image quality and diagnostic capability following randomization and anonymization. The consistency of automatic segmentation results between sequences was explored using an automatic knee cartilage segmentation research application. The descriptive statistics and inter-observer and inter-method concordance of various acceleration sequences were investigated. P values < .05 were considered significant., Results: For image quality evaluation, the image signal-to-noise ratio and contrast-to-noise ratio decreased with the decrease in scanning time. However, it is accompanied by the reduction of artifacts. Using 3D-DESS without parallel acceleration technique as the standard for cartilage grading diagnosisand the diagnostic agreement of two- and fourfold CAIPIRINHA-accelerated 3D-DESS was good, kappa value was 0.860 (P < .001) and 0.804 (p < 0.001), respectively. Regarding cartilage defects, the sensitivity and specificity of the twofold acceleration 3D-CAIPIRINHA-DESS were 95.56% and 97.70%, and the fourfold CAIPIRINHA-accelerated 3D-DESS were 91.49% and 97.65%, respectively. The intraclass correlation coefficients of various sequences in cartilage segmentation were almost all greater than 0.9., Conclusion: The CAIPIRINHA-accelerated 3D-DESS sequence maintained comparable diagnostic and segmentations performance of knee cartilage after a 60% scan time reduction., (© 2024. The Author(s), under exclusive licence to International Skeletal Society (ISS).)

Objectives: This study investigated the use of radiomics for diagnosing early-stage osteonecrosis of the femoral head (ONFH) by extracting features from multiple MRI sequences and constructing predictive models., Materials and Methods: We conducted a retrospective review, collected MR images of early-stage ONFH (102 from institution A and 20 from institution B) and healthy femoral heads (102 from institution A and 20 from institution B) from two institutions. We extracted radiomics features, handled batch effects using Combat, and normalized features using z-score. We employed the Least absolute shrinkage and selection operator (LASSO) algorithm, along with Max-Relevance and Min-Redundancy (mRMR), to select optimal features for constructing radiomics models based on single, double, and multi-sequence MRI data. We evaluated performance using receiver operating characteristic (ROC) and precision-recall (PR) curves, and compared area under curve of ROC (AUC-ROC) values with the DeLong test. Additionally, we studied the diagnostic performance of the multi-sequence radiomics model and radiologists, compared the diagnostic outcomes of the model and radiologists using the Fisher exact test., Results: We studied 122 early-stage ONFH and 122 normal femoral heads. The multi-sequence model exhibited the best diagnostic performance among all models (AUC-ROC, PR-AUC for training set: 0.96, 0.961; validation set: 0.96, 0.97; test set: 0.94, 0.94), and it outperformed three resident radiologists on the external testing group with an accuracy of 87.5 %, sensitivity of 85.00 %, and specificity of 90.00 % (p < 0.01), highlighting the robustness of our findings., Conclusions: Our study underscored the novelty of the multi-sequence radiomics model in diagnosing early-stage ONFH. By leveraging features extracted from multiple imaging sequences, this approach demonstrated high efficacy, indicating its potential to advance early diagnosis for ONFH. These findings provided important guidance for enhancing early diagnosis of ONFH through radiomics methods, offering new avenues and possibilities for clinical practice and patient care., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Intervertebral disc herniation, defined as the protrusion or extrusion of the disc mass outside the disc space, is common and easy to diagnose on conventional Magnetic Resonance imaging (MRI) or Computed Tomography (CT) scans. However, the sequestrated disc fragments are challenging to detect, and intervertebral disc mass displacement into the dural sac, which can lead to serious neurological problems such as Cauda equina syndrome (CES). The sequestrated disc fragments do not have specific clinical or radiological characteristics that can differentiate an atypical disc mass from a tumor, making the diagnosis difficult preoperatively. Herein, we describe the use of Sampling Perfection with Application Optimized Contrast using different flip angle Evolution in Magnetic Resonance Imaging (3D SPACE MRI) in the diagnosis of the intervertebral disc fragment that mimicked a tumor., Case Presentation: In this study, we report two cases of sequestered lumbar disc herniation. The first case was a 37-year-old patient with a 2-year history of intermittent left lower limb pain that aggravates with exercise and is relieved at rest, while the second case was a 42-year-old patient with a history of 40 days of numbness and pain in the left lower limb., Conclusion: 3D SPACE MRI is a beneficial diagnostic imaging tool for discriminating between disc mass that mimics a tumor and a tumor before surgery. If the disc fragment mimicking a tumor can be identified before the operation, open surgical treatment won't be necessary for all patients., (Copyright Journal of Radiology Case Reports.)

Background: pH MRI may provide useful information to evaluate metabolic disruption following ischemia. Radiofrequency amplitude-based creatine chemical exchange saturation transfer (CrCEST) ratiometric MRI is pH-sensitive, which could but has not been explored to examine muscle ischemia., Purpose: To investigate skeletal muscle energy metabolism alterations with CrCEST ratiometric MRI., Study Type: Prospective., Animal Model: Seven adult New Zealand rabbits with ipsilateral hindlimb muscle ischemia., Field Strength/sequence: 3 T/two MRI scans, including MRA and CEST imaging, were performed under two B 1 amplitudes of 0.5 and 1.25 μT after 2 hours of hindlimb muscle ischemia and 1 hour of reperfusion recovery, respectively., Assessment: CEST effects of two energy metabolites of creatine and phosphocreatine (PCrCEST) were resolved with the multipool Lorentzian fitting approach. The pixel-wise CrCEST ratio was quantified by calculating the ratio of the resolved CrCEST peaks under a B 1 amplitude of 1.25 μT to those under 0.5 μT in the entire muscle., Statistical Tests: One-way ANOVA and Pearson's correlation. P < 0.05 was considered statistically significant., Results: MRA images confirmed the blood flow loss and restoration in the ischemic hindlimb at the ischemia and recovery phases, respectively. Ischemic muscles exhibited a significant decrease of PCr at the ischemia (under both B 1 amplitudes) and recovery phases (under B 1 amplitude of 0.5 μT) and significantly increased CrCEST from normal tissues at both phases (under both B 1 levels). Specifically, CrCEST decreased, and PCrCEST increased with the CrCEST ratio. Significantly strong correlations were observed among the CrCEST ratio, and CrCEST and PCrCEST under both B 1 levels (r > 0.80)., Data Conclusion: The CrCEST ratio altered substantially with muscle pathological states and was closely related to CEST effects of energy metabolites of Cr and PCr, suggesting that the pH-sensitive CrCEST ratiometric MRI is feasible to evaluate muscle injuries at the metabolic level., Evidence Level: 2 TECHNICAL EFFICACY STAGE: 1., (© 2023 International Society for Magnetic Resonance in Medicine.)

To investigate the feasibility of readout-segmented diffusion-weighted (rsDW) magnetic resonance (MR) in assessing nerve invasion of soft tissue tumor. Forty-four patients with soft tissue mass in upper leg suspected of nerve invasion underwent rsDW MR. Nerve invasion by tumor was rated by 2 radiologists, respectively. Sensitivity and specificity of rsDW MR in identifying nerve invasion were calculated, with operation findings as reference of standard. Apparent diffusion coefficient and fraction of anisotropy of nerve were obtained using DW MR, and then were compared between invaded nerves and noninvasion cases. Inter-reader agreement in using rsDW MR to rate nerve invasion was excellent (kappa = 0.891 ± 0.043, P < 0.001). Sensitivity and specificity of rsDW MR in identifying nerve invasion were 89% and 88%, respectively. Apparent diffusion coefficient was significantly higher in invaded nerves versus normal nerves (1.45 ± 0.67 × 10-3 mm2/s vs 1.39 ± 0.46 × 10-3 mm2/s, P < 0.05). Fraction of anisotropy was significantly lower in invaded nerves versus normal nerves (0.22 ± 0.11 vs 0.37 ± 0.13, P < .05). Readout-segmented DW MR was feasible in assessing sciatic nerve invasion by soft tissue tumor in selected patients., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: The discrimination of acute and chronic deep venous thrombosis (DVT) is of great importance. Quantitative imaging is an urgent requirement in reflecting intrinsic characteristics of thrombosis., Purpose: To investigate the feasibility of T1 mapping in staging DVT in the lower extremities., Material and Methods: A total of 57 patients with DVT in the lower extremities (26 men, 31 women; mean age = 53.3 years) underwent T1-weighted imaging and T1 mapping for obtaining T1 signal intensity (SI) and T1 time of thrombus. The relative SI (rSI) of DVT was obtained by calculating the ratio of thrombus SI to muscle SI. The Mann-Whitney U test was used to compare rSI and T1 time of DVT between acute group (patients with limb edema ≤ 2 weeks) and chronic group (patients with limb edema > 2 weeks). A receiver operator characteristic (ROC) curve was constructed for further evaluation., Results: DVT rSI was significantly higher in the acute group versus the chronic group (2.8 ± 1.2 vs. 1.4 ± 0.6; P <0.05). DVT T1 time was significantly lower in the acute group versus the chronic group (819.4 ± 223.7 ms vs. 1264.8 ± 270.7 ms; P <0.05). The area under the curve (AUC) was 0.93 for T1 time and 0.75 for rSI. When using 1015 ms as the cut-off, the sensitivity and specificity of T1 time were 91% (32/35) and 86% (19/22), respectively., Conclusion: T1 mapping is a potential technique in discriminating acute from chronic DVT in the lower extremities and warrants further investigation.

Objectives: To compare the performance of 6-min MRI with a fat-saturated 3D-controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) Sampling perfection with application-optimized contrast using different flip angle evolution (SPACE) TSE protocol with 10-min 2D TSE MRI protocol for assessment of abnormalities of the shoulder., Methods: Forty-nine subjects underwent both 3D fat-saturated-CAIPIRINHA SPACE and 2D TSE sequences of the shoulder on a 3.0-T system. Following randomization and anonymization, two musculoskeletal radiologists evaluated the 2D and 3D images independently for image quality and diagnostic capability. Descriptive statistics, inter-observer, and inter-method concordance were investigated. p values < 0.05 were considered significant., Results: For image quality assessment, 2D images were similar to 3D CAIPIRINHA SPACE images (p = 0.05). 3D had lower noise standard deviation (SD) and higher fluid CNR than 2D images (p = 0.00). For diagnostic capability assessment, using 2D TSE as a standard of reference, sensitivity, specificity, and accuracy of 3D SPACE were, respectively, 94.81%, 94.12%, and 94.39% for tendon abnormalities; 97.06%, 80.00%, and 91.84% for acromioclavicular joint abnormalities; 88.89%, 100.00%, and 93.89% for adjacent bone alterations; and 97.30%, 100%, and 97.96% for joint fluid/effusion assessment. The inter-method concordance was moderate to almost perfect. The inter-observer-concordance of the shoulder assessment was also moderate to almost perfect, with SSP lesions demonstrating the greatest concordance., Conclusions: The performance of 6-min 3D fat-saturated-CAIPIRINHA SPACE MRI for shoulder MRI is similar to that of 10-min 2D TSE MRI. 3D fat-saturated-CAIPIRINHA SPACE MRI can be utilized to reduce scan time without degradation in image quality., Key Points: • CAIPIRINHA acceleration 3D fat-saturated-MRI of the shoulder is achievable in 6 min with high spatial resolution. • 3D fat-saturated CAIPIRINHA MRI is similar to 2D MRI in the shoulder assessment. • 3D CAIPIRINHA MRI images enable rapid diagnosis of shoulder abnormalities without image quality degradation., (© 2021. European Society of Radiology.)

Objective: To investigate the value of radiomics analyses based on different magnetic resonance (MR) sequences in the noninvasive evaluation of glioma characteristics for the differentiation of low-grade glioma versus high-grade glioma, isocitrate dehydrogenase (IDH)1 mutation versus IDH1 wild-type, and mutation status and 6-methylguanine-DNA methyltransferase (MGMT) promoter methylation (+) versus MGMT promoter methylation (-) glioma., Methods: Fifty-nine patients with untreated glioma who underwent a standard 3T-MR tumor protocol were included in the study. A total of 396 radiomics features were extracted from the MR images, with the manually delineated tumor as the volume of interest. Clinical imaging diagnostic features (tumor location, necrosis/cyst change, crossing midline, and the degree of enhancement or peritumoral edema) were analyzed by univariate logistic regression to select independent clinical factors. Radiomics and combined clinical-radiomics models were established for grading and molecular genomic typing of glioma by multiple logistic regression and cross-validation. The performance of the models based on different sequences was evaluated by using receiver operating characteristic curves, nomograms, and decision curves., Results: The radiomics model based on T1-CE performed better than models based on other sequences in predicting the tumor grade and the IDH1 status of the glioma. The radiomics model based on T2 performed better than models based on other sequences in predicting the MGMT methylation status of glioma. Only the T1 combined clinical-radiomics model showed improved prediction performance in predicting tumor grade and the IDH1 status., Conclusions: The results demonstrate that state-of-the-art radiomics analysis methods based on multiparametric MR image data and radiomics features can significantly contribute to pretreatment glioma grading and molecular subtype classification., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

The aim of the study is to verify the effect of hyperglycemia on ischemia-reperfusion injury and to explore the feasibility of noninvasive observation of ischemic-reperfusion injury in hyperglycemic ischemic stroke by MRI technique. According to the duration of ischemia and blood glucose levels, 40 rats were divided into hyperglycemic ischemic 2-hr (H-I2h), hyperglycemic ischemic 6-hr (H-I6h), non- hyperglycemic ischemic 2-hr (NH-I2h), and non- hyperglycemic ischemic 6-hr (NH-I6h) groups. T2W imaging, DW imaging, T2 mapping, T2* mapping, DCE, and T1 mapping after enhancement sequences were acquired before reperfusion and approximately 3-hr after reperfusion. ADC, T1, T2, T2*, and K trans values of ischemic lesion were obtained in different groups. After reperfusion, the variation of ADC values showed no significant difference between groups with diabetes and groups without diabetes and between different recanalization time-points (2-hr vs 6-hr). After reperfusion, T2, T2*, and K trans values increased in different degrees in all four groups. Only the T1 value decreased in all groups. The change of all parameters in groups with hyperglycemia was more obvious than that in groups without hyperglycemia and was more obvious in groups with H-I6h versus those with H-I2h. This study confirms that hyperglycemia aggravates ischemia-reperfusion injury and may be an important risk factor for the prognosis of ischemic stroke. The K trans values should be noninvasive imaging indicators to monitor blood brain barrier permeability and ischemic-reperfusion injury in ischemic stroke.

Objectives: The aim of this study was to evaluate the diagnostic performance of noncontrast magnetic resonance imaging utilizing sampling perfection with application optimized contrasts using different flip angle evolutions (SPACE) in detecting deep venous thrombus (DVT) of the lower extremity and evaluating clot burden., Materials and Methods: This prospective study was approved by the institutional review board. Ninety-four consecutive patients (42 men, 52 women; age range, 14-87 years; average age, 52.7 years) suspected of lower extremity DVT underwent ultrasound (US) and SPACE. The venous visualization score for SPACE was determined by 2 radiologists independently according to a 4-point scale (1-4, poor to excellent). The sensitivity and specificity of SPACE in detecting DVT were calculated based on segment, limb, and patient, with US serving as the reference standard. The clot burden for each segment was scored (0-3, patent to entire segment occlusion). The clot burden score obtained with SPACE was compared with US using a Wilcoxon test based on region, limb, and patient. Interobserver agreement in assessing DVT (absent, nonocclusive, or occlusive) with SPACE was determined by calculating Cohen kappa coefficients., Results: The mean venous visualization score for SPACE was 3.82 ± 0.50 for reader 1 and 3.81 ± 0.50 for reader 2. For reader 1, sensitivity/specificity values of SPACE in detecting DVT were 96.53%/99.90% (segment), 95.24%/99.04% (limb), and 95.89%/95.24% (patient). For reader 2, corresponding values were 97.20%/99.90%, 96.39%/99.05%, and 97.22%/95.45%. The clot burden assessed with SPACE was not significantly different from US (P > 0.05 for region, limb, patient). Interobserver agreement of SPACE in assessing thrombosis was excellent (kappa = 0.894 ± 0.014)., Conclusions: Non-contrast-enhanced 3-dimensional SPACE magnetic resonance imaging is highly accurate in detecting lower extremity DVT and reliable in the evaluation of clot burden. SPACE could serve as an important alternative for patients in whom US cannot be performed.

Background and Purpose: Early prediction of functional outcome in cerebral ischemia stroke using MRI remains a challenge. The aim of this study was to evaluate the predictive value of dynamic contrast-enhanced (DCE) MRI in terms of functional outcome of ischemia stroke., Methods: Right middle cerebral artery occlusion (MCAO) was performed in male SD rats (n=50), followed by withdrawal of the occluding filament after 3 (n = 10), 4 (n = 10), 5 (n = 10), 6 (n = 10) or 7 (n = 10) h to establish ischemia and reperfusion stroke. DCE and conventional MRI were performed in each animal 60 ± 15 min before and after reperfusion. The outcome was assessed by the modified Neurological Severity Scores (mNSS) (before reperfusion and at 72 h after reperfusion) and the infarct volume. Comparisons of functional prognosis and DCE parameters (K(trans), Ve and Kep) were performed using binary logistic regression and operating characteristic (ROC) analysis., Results: DCE parameters results indicated that blood brain barrier (BBB) permeability increased with prolonged reperfusion timing. Using binary logistic regression analysis on stroke characteristics (reperfusion timing, infarct volume) and BBB permeability parameters (drK(trans)subcortex, drK(trans)cortex, drVesubcortex, drVecortex, drKepsubcortex and drKepcortex) as covariates , the results demonstrated that reperfusion timing, infarct volume, drK(trans)subcortex and drKepsubcortex were independent factors that were associated with prognosis (OR=0.01, OR=0.23, OR=245.23, OR=1.29). ROC analysis indicated that a drK(trans)subcortex threshold of 0.88 with a sensitivity of 95.7% and a specificity of 85.2% and a drKepsubcortex threshold of -0.25 with a sensitivity of 69.6% and a specificity of 70.4% for differentiation between favourable and unfavourable prognosis., Conclusions: Quantitative DCE-MRI can be used to predict the functional outcomes of cerebral ischemia injury., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background and Purpose: Reperfusion-associated hemorrhagic transformation (HT) is an important complication of recanalization therapy. A method to identify stroke victims that may undergo HT will improve the patient selection and safety of this treatment. In this study, we determined the relationship between timing of reperfusion and the frequency and severity of HT, and whether very early dynamic contrast-enhanced (DCE) imaging predicts the occurrence of reperfusion-associated HT in a model of experimental stroke., Methods: Intraluminal suture occlusion of the middle cerebral artery was used to produce transient ischemia in male Sprague Dawley rats (n = 50). Reperfusion was performed by withdrawal of the occluding filament after 3 (n = 10), 4 (n = 10), 5 (n = 10), 6 (n = 10), or 7 (n = 10) hours. Magnetic resonance imaging studies were performed before reperfusion using DCE, susceptibility-weighted imaging, diffusion-weighted imaging, and T2- and T1-weighted imaging. Follow-up magnetic resonance imaging and histological studies were performed at 24 hours., Results: Hemorrhagic transformation occurred by 24 hours after injury in 8 of 50 animals. The HT rate increased with prolonged ischemic duration. All animals exhibiting acute blood-brain barrier (BBB) perturbation subsequently developed HT by 24 hours. Statistically significant differences in the BBB permeability parameters (P < 0.05) between the HT group and non-HT group were detected by DCE imaging. There were also statistically significant differences (P < 0.05) between the HT area and adjacent HT area. Among the permeability parameters, subcortex rK was the most sensitive and specific predictor of HT., Conclusions: The results suggest that the use of quantitative BBB measurements may further improve early prediction and identification of HT. The DCE parameters were the sensitive early independent predictor of reperfusion-associated HT.

Background: Extrapulmonary small cell carcinoma is a distinct clinicopathological entity accounting for only 2.5-4% of small cell carcinomas. Here we present a case of primary intracranial small cell carcinoma., Case Report: A 69-year-old woman with an isolated brain lesion presented with progressive headaches, confusion, nausea, and vomiting. A magnetic resonance imaging scan of the brain revealed a 4 × 3 × 5-cm solitary cystic tumor in the right frontoparietal lobe, accompanied by a midline shift. The mass was resected and pathologically proven to be a small cell carcinoma. The patient was given adjuvant radiotherapy but refused any chemotherapy. At the 12-month follow-up the patient was alive and well., Conclusion: Primary intracranial small cell carcinoma presenting as an isolated lesion is extremely rare. While there are no standard treatment guidelines for these patients, the authors believe multimodality treatment including tumorectomy and postoperative radiotherapy should be recommended., (© 2013 S. Karger GmbH, Freiburg.)

Magnetic resonance imaging (MRI) has been widely used in intracerebral hemorrhage (ICH) animal models and patients. In the current study, we examined whether MRI can predict at-risk brain tissue during the acute phase and long-term brain tissue loss after ICH. Male Sprague-Dawley rats had an intracaudate injection of autologous whole blood (10, 50 or 100 μL). MRI (T2 and T2*) sequences were performed at days 1, 3, 7, 14, and 28. The volume of brain tissue at risk was calculated as the difference between T2 and T2* lesion volumes. Dopamine- and cAMP-regulated phosphoprotein, Mr 32 kDa (DARPP-32) was used as a neuronal marker in the basal ganglia. Brain swelling at day 3 and brain tissue loss at day 28 after ICH were also measured. We found that the difference in lesion volumes between T2 and T2* measured by MRI coincided well with the difference between the volume of the DARPP-32-negative area and that of the hematoma measured in brain sections. Volumes of brain tissue at risk at day 3 correlated with the brain swelling at day 3 (p < 0.01) as well as the final brain tissue loss at day 28 (n = 9, p < 0.05). The results suggest that the difference between T2 lesions and T2* lesions could be an indicator of at-risk brain tissue and it could be used as a predictor of neuronal loss in ICH patients.

Based on the properties of photodynamic therapy (PDT) and magnetic resonance imaging (MRI), combining them to construct multifunctional nanotheranostics can leverage strengths and avoid weaknesses for tumor diagnosis and treatment. However, certain problems remain unsolved, notably the short observation window caused by insufficient retention time. In this study, a GSH‐responsive shape‐transformable nanotheranostics Gd‐Ce6‐FFVLGGGC‐SS‐PEG are designed (abbreviated as GdCFS) by combining a single metal Gd with Ce6, and peptide (Phe‐Phe‐Val‐Leu‐Gly‐Gly‐Gly‐Cys) disulfide‐conjugated with polyethylene glycol (PEG) to perform dual‐modal T1/T2 MRI specifically at the tumor site. Due to its amphiphilic features, GdCFS can self‐assemble to spherical nanoparticles, while transforming to nanofibers (NFs) in the presence of intracellular overexpressed GSH stimuli. After NFs formation, the hydrophobic core of GdCFS is exposed, resulting in T1 positive contrast enhancement, whereas NFs can simultaneously achieve T2 negative contrast enhancement. Furthermore, GSH depletion can cause imbalance in intracellular redox state, ultimately improving PDT efficacy. GdCFS benefits from the shape‐transformation in terms of sufficient retention time, thus positively minimizing the toxicity risk. On the tumor model of nasopharyngeal carcinoma, in vivo and in vitro outcomes confirm that GdCFS can be a promising candidate for early diagnosis, real‐time monitoring, and precise treatment of tumors with great biocompatibility. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the reliability of a deep neural network (DNN) model trained only on contrast-enhanced T1 (T1CE) images for predicting intraoperative cerebrospinal fluid (ioCSF) leaks in endoscopic transsphenoidal surgery (EETS). Methods: 396 pituitary adenoma (PA) cases were reviewed, only primary PAs with Hardy suprasellar Stages A, B, and C were included in this study. The T1CE images of these patients were collected, and sagittal and coronal T1CE slices were selected for training the DNN model. The model performance was evaluated and tested, and its interpretability was explored. Results: A total of 102 PA cases were enrolled in this study, 51 from the ioCSF leakage group, and 51 from the non-ioCSF leakage group. 306 sagittal and 306 coronal T1CE slices were collected as the original dataset, and data augmentation was applied before model training and testing. In the test dataset, the DNN model provided a single-slice prediction accuracy of 97.29%, a sensitivity of 98.25%, and a specificity of 96.35%. In clinical test, the accuracy of the DNN model in predicting ioCSF leaks in patients reached 84.6%. The feature maps of the model were visualized and the regions of interest for prediction were the tumor roof and suprasellar region. Conclusion: In this study, the DNN model could predict ioCSF leaks based on preoperative T1CE images, especially in PAs in Hardy Stages A, B, and C. The region of interest in the model prediction-making process is similar to that of humans. DNN models trained with preoperative MRI images may provide a novel tool for predicting ioCSF leak risk for PA patients. [ABSTRACT FROM AUTHOR]

Objectively reflect the stability of aneurysms by judging the morphology, SR value, and signal enhancement of UIA, and can provide a certain basis for diagnosis and treatment, which has become routine examination. [ABSTRACT FROM AUTHOR]

Objective: To analyse the image characteristics of fibro-adipose vascular anomaly (FAVA) and the value of ultrasound and magnetic resonance imaging (MRI) for its diagnosis. Methods: The clinical and imaging data characteristics of 10 patients with FAVA admitted to our hospital between January 2018 and December 2020 who underwent ultrasound and MRI diagnosis were retrospectively analysed. Results: A total of 10 patients (six males and four females) with pathologically confirmed FAVA, aged from 3 to 27 years (median: 13 years), underwent ultrasound and MRI; of these, two patients underwent MRI-enhanced examinations. All lesions involved mainly muscle, with a few disruptions and involvements of subcutaneous fat. Five cases were located subcutaneously near the fascia; one case was adjacent to the periosteum. Ultrasound showed fascial tail in seven cases, and MRI showed fascial tail in six cases. Both ultrasound and MRI showed the lesions to be oval-shaped masses with blurred borders and a mean maximum diameter of 99.8 ± 48.7 mm. Ultrasound showed a mass with a mixture of high and low echoic areas. Magnetic resonance imaging imaging showed a heterogeneous, mixed-signal intensity on T1-weighted images, probably influenced by the fibrous and fatty components of the lesion. T2-weighted images showed a mixed-high signal. Enhanced computed tomography scans showed significant heterogeneous enhancement of the lesions. Conclusion: Both ultrasound and MRI showed that fascial tail sign is an important imaging feature for FAVA disease; this provides a reliable basis for its diagnosis and can be used to distinguish it from venous malformations, which have no fascial tail signs. Therefore, fascial tail signs can be used as imaging features and require special attention in the diagnosis of FAVA disease. [ABSTRACT FROM AUTHOR]

Background: The percutaneous transforaminal endoscopic lumbar interbody fusion (PETLIF) has many advantages as a new minimally invasive surgical technique, and its surgical approach passes through the Kambin's triangle. One of the greatest challenges in completing PETLIF is avoiding nerve root damage. In previous studies, the relevant anatomic data do not correspond well with current surgical techniques, and there is a paucity of studies based on magnetic resonance neurography (MRN), which is the clearest imaging method for nerve roots. The purpose of this study was to analyze the safety of the PETLIF at each lumbar segment based on measured results from the MRN imaging data and to propose a novel method of intraoperative positioning. Methods: The coronal images with the clearest course of nerve roots were chosen for retrospective observation. During the PETLIF, the secure region of the operation was considered to be a trapezium. The following parameters were measured, respectively: trapezoid area, height, and median line length, as well as the relevant parameters of the positional relation between the point "O," the most secure operating center point of the secure region, and each osseous anatomic landmark. And the data were compared with the size of the cage to obtain safety. Results: At L1-S1, with the downward motion of the target intervertebral space, the area increased from (67.94 ± 15.22) mm2 to (140.99 ± 26.06) mm2, and the height increased from (7.23 ± 1.17) mm to (12.59 ± 1.63) mm. At L1–L5, the length of the median line was increased from (9.42 ± 1.70) mm to (12.70 ± 1.88) mm. Even though it was reduced to (11.59 ± 1.99) mm at L5–S1, it was still longer than that at L3–L4. The safety obtained by the primary observational indicator was 34.52%, 33.33%, 53.57%, 96.43%, and 77.38%, respectively, at L1–S1. The safety obtained by the two secondary observational indicators was 77.38% and 95.24% at L3–L4 and 100% at L4–S1. There was no point "O" outside the anatomic mark line. The intraoperative positioning method of the point "O" was as follows: It was located medially and horizontally approximately 3/5 of the anatomic mark line at L1–L5; the horizontal distances were (0.48 ± 0.67) mm, (1.20 ± 0.89) mm, (2.72 ± 1.01) mm, and (3.69 ± 1.47) mm, respectively. In addition, it was necessary to locate (3.43 ± 1.41) mm inward at about 4/5 of the anatomic mark line at L5–S1. Conclusions: The MRN allows clearer and more accurate visualization of the nerve roots, and the basic anatomic study of the Kambin's triangle based on this technology is of practical clinical significance. In the current study, it is believed that, during the PETLIF, cage implantation is the safest at L4–L5, followed by L5–S1; L1–L3 is more likely to cause nerve root injury, and L3–L4 is not less likely. To improve safety, a comprehensive individualized imaging assessment should be performed before surgery. This study also provides an easy method of intraoperative localization, which helps avoid nerve root injury. [ABSTRACT FROM AUTHOR]

Purpose: Vessel wall MRI (VW-MRI) can be used to evaluate the nature of intracranial atherosclerosis (ICAS) plaque in vivo. Phosphodiesterase 4D (PDE4D) participates in stroke development. This study aims to explore the value of VW-MRI findings and the PDE4D gene variant in predicting stroke recurrence in patients with ICAS. Methods: We prospectively recruited 324 symptomatic ICAS patients. VW-MRI was performed to determine luminal and wall changes. PDE4D gene single-nucleotide polymorphisms (SNPs)—namely, SNP32, SNP83, and SNP87—were determined by direct sequencing. The risk factors of stroke recurrence were analyzed using the multivariate Cox proportional hazards model. Results: Of the 324 subjects, 97 (29.9%) experienced recurrent ischemic stroke during the follow-up period. A total of 254 patients (78.4%) showed plaque enhancement; 87 of these patients experienced stroke recurrence. The CT/CC genotype frequencies of PDE4D83 were significantly higher in participants with recurrent stroke than in patients without stroke recurrence (p = 0.019 and p < 0.001, respectively). However, the PDE4D32 and PDE4D87 variants were not correlated with recurrent stroke. Multivariate analysis showed that plaque enhancement from VW-MRI (HR 4.52, 95% CI 2.35–8.73, p < 0.001) and the PDE4D83 variant (HR 7.43, 95% CI 1.75–31.87, p = 0.005) were independently correlated with stroke recurrence. Kaplan–Meier curves showed significant differences in stroke recurrence rates between the plaque-enhanced group and the non-enhanced group (p < 0.001) and between the PDE4D83 variant carriers and noncarriers (p = 0.002). Conclusion: Plaque enhancement on VW-MRI and the presence of the PDE4D83 variant are associated with ischemic stroke recurrence in subjects with symptomatic ICAS. [ABSTRACT FROM AUTHOR]

Background: Brain Magnetic Resonance Imaging (MRI) examination of cerebral small vessel disease (CSVD) may help screen vascular cognitive impairment. A recently estimated CSVD score system was suggested to capture the overall CSVD burden. The study aimed to detect the association between systemic evaluation score of cerebral vascular imaging parameters with cognitive functions. Methods: This was a cross-sectional study in community settings. From October 2017 to September 2018, elder (≧60) residents were recruited through on-site visit in 6 communities from Shanghai, China. The participants underwent brain MRI, carotid ultrasound, laboratory tests of blood and urine samples. Cognitive function was evaluated using Mini-Mental State Examination (MMSE). MRI score of CSVD was calculated according to the 2012 standard for the evaluation of statistical changes in imaging. Results: Total 171 subjects completed survey and examinations. There were 55 participants diagnosed with cognitive impairment, with a total percentage of 32.2%. Participants with and without cognitive impairment showed significant differences in age, BMI and education level. Cognitive impaired participant had more disease history/comorbidity of hypertension and chronic renal insufficiency, higher level of creatinine, as well as lower level of full blood count (FBC) and alanine aminotransferase (ALT). A significant difference was detected in CSVD score between participants with and without cognitive impairment. Results of linear regression analysis showed significant negative correlations between MMSE score and both left and right carotid artery peak systolic velocity (PSV), however the CSVD score was only borderline (P = 0.0566) positively correlated with MMSE. Multivariate linear correlation analysis including all collected risk factor data showed that left carotid artery PSV score was among the independent negative correlated factors of MMSE. Multivariate binary logistic analysis showed that age, education and history of hypertension were the only statistically associated factors of cognitive impairment. Conclusions: The current study identified high prevalence of cognitive impairment in a Chinese community. In addition, correlations between cerebral vascular disease imaging status and cognitive functions were confirmed although the sample size limited the possibility of screening cognitive impairment with imaging technique. [ABSTRACT FROM AUTHOR]

This study aims to build a radiological model based on standard MR sequences for detecting methylguanine methyltransferase (MGMT) methylation in gliomas using texture analysis. A retrospective cross‐sectional study was undertaken in a cohort of 53 glioma patients who underwent standard preoperative magnetic resonance (MR) imaging. Conventional visual radiographic features and clinical factors were compared between MGMT promoter methylated and unmethylated groups. Texture analysis extracted the top five most powerful texture features of MR images in each sequence quantitatively for detecting the MGMT promoter methylation status. The radiomic signature (Radscore) was generated by a linear combination of the five features and estimates in each sequence. The combined model based on each Radscore was established using multivariate logistic regression analysis. A receiver operating characteristic (ROC) curve, nomogram, calibration, and decision curve analysis (DCA) were used to evaluate the performance of the model. No significant differences were observed in any of the visual radiographic features or clinical factors between different MGMT methylated statuses. The top five most powerful features were selected from a total of 396 texture features of T1, contrast‐enhanced T1, T2, and T2 FLAIR. Each sequence's Radscore can distinguish MGMT methylated status. A combined model based on Radscores showed differentiation between methylated MGMT and unmethylated MGMT both in the glioblastoma (GBM) dataset as well as the dataset for all other gliomas. The area under the ROC curve values for the combined model was 0.818, with 90.5% sensitivity and 72.7% specificity, in the GBM dataset, and 0.833, with 70.2% sensitivity and 90.6% specificity, in the overall gliomas dataset. Nomogram, calibration, and DCA also validated the performance of the combined model. The combined model based on texture features could be considered as a noninvasive imaging marker for detecting MGMT methylation status in glioma. [ABSTRACT FROM AUTHOR]

Background: Whether unilateral or bilateral drainage should be performed for malignant hilar biliary obstruction remains a matter of debate. Although a Y-stent with a central wide-open mesh facilitates bilateral stent placement, it has its own limitations.Aim: This study aims to evaluate the feasibility and efficacy of a newly designed Y-configured bilateral self-expanding metallic stent (SEMS) for the treatment of hilar biliary obstruction.Methods: In this retrospective study, 14 consecutive patients with unresectable malignant hilar biliary obstruction (Bismuth type II or higher), who underwent placement of a newly designed Y-configured bilateral SEMS for hilar biliary obstruction from April 2013 to March 2015, were included into this study. Data on technical success, clinical success, stent patency, complications and patient survival were collected.Results: Technical and clinical success was 100 and 92.9 %, respectively. Mean serum bilirubin level was significantly decreased 1 month after stent placement (P < 0.01). Furthermore, two patients (14.3 %) had early complications (one patient had severe hemobilia and one patient had cholangitis), and two patients (14.3 %) had late complications (one patient had cholangitis and one patient had cholecystitis). During the mean follow-up period of 298 days (range 89-465 days), six patients (42.9 %) developed stent occlusion caused by tumor ingrowth or overgrowth (n = 5) and sludge (n = 1). Median stent patency and overall survival times were 281 days (95 % CI 175.9-386.1 days) and 381 days (95 % CI 291.4-470.6 days), respectively.Conclusion: The use of the newly designed Y-configured bilateral SEMS is feasible and effective for hilar biliary obstruction using port docking deployment. [ABSTRACT FROM AUTHOR]

Background: Nowadays, flat detector (FD) equipped angiographic C-arm computed tomography (CACT) systems can be used to acquire CT-like cross-sectional images directly within the interventional suite. The CACT systems offer real time visualization of transthoracic needle biopsy (TNB) procedure and more flexibility in the orientation of the detector system around the patient compared to traditional CT systems.Purpose: To evaluate the value of a flat detector C-arm CT-guidance system in performing percutaneous transthoracic needle biopsy (PTNB) for small (≤3 cm) pulmonary lesions in clinical practice.Material and Methods: A total of 60 patients with solid lung lesions were retrospectively enrolled to undergo PTNB procedures. The mean diameter of lesions was 2.3 ± 0.6 cm (range, 0.6-3 cm). The needle path was carefully planned and calculated on the C-arm CT system, which acquired three-dimensional CT-like cross-sectional images. The PTNB procedures were performed under needle guidance with fluoroscopic feedbacks.Results: Histopathologic tissue was successfully obtained from 59 patients with a puncture success rate of 98.3% (59/60). The diagnostic accuracy rate was found to be 91.5% (54/59). There were only two cases of pneumothorax (3.3%) requiring therapy. The rates of pneumothorax and hemoptysis were low (15.0% [9/60] and 8.3% [5/60], respectively). The overall procedural time was in the range of 12-18 min, resulting in a mean exposure dose of 224.4 ± 4.8 mGy.Conclusion: Our study shows that C-arm CT-based needle guidance enables reliable and efficient needle positioning and progression by providing real-time intraoperative guidance for small (≤3 cm) pulmonary lesions in clinical practice. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the type of venous involvement in Chinese Budd-Chiari syndrome (BCS) patients and the relative diagnostic accuracy of the different imaging modalities. Methods: Using digital subtraction angiography (DSA) as a reference standard, color Doppler ultrasound (CDUS), computed tomography angiography (CTA), and magnetic resonance angiography (MRA) were performed on 338 patients with BCS. We analyzed the course of the main and any accessory hepatic veins (HVs) and the inferior vena cava (IVC) to assess the etiology of obstructed segments and diagnostic accuracy of CDUS, CTA and MRA. Results: Among the 338 cases, there were 8 cases (2.4%) of isolated IVC membranous obstruction, 45 cases (13.3%) of isolated HV occlusion, and 285 cases (84.3%) with both IVC membranous obstruction and HV occlusion. Comparing with DSA, CDUS, CTA had a diagnostic accuracy of 89.3% and 80.2% in detecting BCS, and 83.4% of cases correctly correlated by MRA. Conclusion: In Henan Province, most patients with BCS have complex lesions combining IVC and HV involvement. The combination of CDUS and CTA or MRI is useful for diagnosis of BCS and guiding therapy. [ABSTRACT FROM AUTHOR]

Primary thymic atypical carcinoid (TAC) is a type of extremely rare neuroendocrine tumor. Approximately one-third of patients with TAC tumors are asymptomatic, and no treatments of TAC have been rigorously tested in multicenter clinical trials. To date, there has been no previous case report of TACs with multiple skull metastases. The present report describes a case of a 56-year-old male patient with a primary TAC and multiple axial skeleton metastases, including multiple bilateral metastases to the parietal bones, outer wall of the orbital cavities, and the petrous apex, as well as metastases to the suprasellar region and the clivus. The histological examination confirmed the diagnosis of TAC. Single-photon emission computed tomography, computed tomography and magnetic resonance imaging scans revealed multiple bone metastases. The patient refused chemotherapy and radiotherapy and only accepted alleviative treatment, and died 89 days after diagnosis. This type of cancer is highly malignant with an extremely short natural course and high disease-related mortality. In addition, a review of the literature was performed to provide a reference for proper diagnosis and treatment of TACs. [ABSTRACT FROM AUTHOR]

• A nanomotor was fabricated as carrier of photosensitizer (denote as ISP-NMs). • ISP-NMs owned magnetic resonance imaging and tumor targeting functions. • ISP-NMs can be propelled by O 2 to move to enlarge its distribution. • The generated O 2 can alleviate tumor hypoxia to enhance PDT activity. • ISP-NMs showed satisfactory in vitro and in vivo anticancer activity. Amphiphilic block copolymer can self-assemble to stomatocyte-like structure as drug delivery carrier. Photodynamic therapy (PDT) is an emerging modality for cancer treatment. However, PDT has various problems, such as weak tumor accumulation ability of photosensitizers (PSs), short lifetime of singlet oxygen (1O 2 , main reactive oxygen species in PDT) and tumor hypoxia microenvironment, to restrict its therapeutic efficacy. To convey PSs to tumor tissues and improve PDT efficacy, iron oxide nanoparticles (IONPs) were loaded inside the self-assembly stomatocytes-like structure of poly(ethylene glycol) block polystyrene (PEG- b -PS) as nanomotors (IONPs loaded stomatocytes nanomotors, denoted IS-NMs) for PS (zinc phthalocyanine, ZnPc) delivery. The hybrid nanomotors (iron oxide nanoparticles loaded stomatocytes@ZnPc nanomotors, denoted ISP-NMs) can be gathered in tumor tissues under magnetic field owing to magnetism of IONPs. After been trapped by cancer cells, IONPs can catalyze decomposition of endogenous H 2 O 2 to generate O 2 as propelling force for ISP-NMs movement. The motion characteristics of ISP-NMs expanded the distribution of ZnPc to enlarge ROS reactive distribution and enhance the activity of PDT. And the generated O 2 can be supplied for PDT process to ensure its high-performance. Furthermore, ISP-NMs have nuclear magnetic resonance imaging (MRI) function since IONPs are efficient T 2 contrast agent. [ABSTRACT FROM AUTHOR]

Background: The importance of discriminating acute from non-acute thrombus is highlighted. The study aims to investigate the feasibility of readout-segmented diffusion weighted (DW) cardiovascular magnetic resonance (CMR) for discrimination of acute from non-acute deep venous thrombus (DVT). Methods: For this prospective study from December 2015 to December 2017, 85 participants (mean age = 53 years, age range = 34~74) with DVT of lower extremities underwent readout-segmented DW CMR. DVT of ≤14 days were defined as acute (n = 55) and > 14 days as non-acute (n = 30). DVT visualization on b = 0, b = 800, and apparent diffusion coefficient (ADC) images were assessed using a 4-point scale (0~3, poor~excellent). DW CMR parameters were measured using region of interest (ROI). Relative signal intensity (rSI) and ADC were compared between acute and non-acute DVT using a Mann Whitney test. Sensitivity and specificity for ADC and rSI were calculated. Results: ADC maps had higher visualization scores than b = 0 and b = 800 images (2.7 ± 0.5, 2.5 ± 0.6, and 2.4 ± 0.6 respectively, P<0.05). The mean ADC was higher in acute DVT than non-acute DVT (0.56 ± 0.17 × 10− 3 vs. 0.22 ± 0.12 × 10− 3 mm2/s, P<0.001). Using 0.32 × 10− 3 mm2/s as the cutoff, sensitivity and specificity for ADC to discriminate acute from non-acute DVT were 93 and 90% respectively. Sensitivity and specificity were 73 and 60% for rSI on b = 0, and 75 and 63% for rSI on b = 800. Conclusions: Readout segmented diffusion-weighted CMR derived ADC distinguishes acute from non-acute DVT. Trial registration: This study is retrospectively registered. Trial registration number: HUST-TJH-2015-146. [ABSTRACT FROM AUTHOR]

To explore and confirm feasibility the T2 maps and readout-segmented echoplanar imaging (rs-EPI) diffusion-weighted imaging (DWI) characteristics of the thigh muscles for dermatomyositis (DM) patients. This study was approved by the University Institutional Review and written informed consent was obtained from all subjects before enrollment (trial registration number: TJ-C20121221). 28 patients with DM proven by diagnostic criteria were enrolled in the study along with 9 healthy control subjects. Conventional MR, T2 maps and rs-EPI DWI were obtained for all subjects. Both of T2 and apparent diffusion coefficient (ADC) values for thigh muscles were compared between the DM and healthy control groups. The amount of inflammation and fatty infiltration were respectively assigned a score of 0 to 5 for all thigh muscles. The Kruskal–Wallis tests were utilized and the Spearman correlation coefficients models were used to correlate both of the T2 and ADC value with non-quantitative MRI. P-values <0.05 reflected statistical significance. Both of the T2 and ADC values among all affected muscles, unaffected muscles and the control groups were respectively statistical difference (p < 0.05 respectively), the T2 value of affected muscles was greater than that of unaffected muscles in DM patients (p < 0.05). Differences of the T2 value in DM patients among the combination the edematous with fatty infiltration score groups were statistically significant (p < 0.001). The T2 value showed a significant correlation with the non-quantitative MRI score for edema and fatty infiltration. T2 maps may have a specialized ability for the detection severity of damaged muscles in comparison to the rs-EPI DWI sequence. A new application of rs-EPI DWI is proposed for DM patients. First, comparison of T2 maps and rs-EPI DWI technology are applied for DM. The results demonstrate that T2 maps may be more potential value in determining the severity of diseased muscles for DM patients. [ABSTRACT FROM AUTHOR]

Background To explore the clinical characteristics of neurocutaneous melanosis (NCM) in adult patients to help improve diagnosis and treatment of this disease, we present a rare case of an adult patient suffering from NCM with malignant melanoma, as well as a review of the relevant Chinese and English literature. Case Description The patient reported here plus the patients identified in our literature review total 30 adults with NCM (20 males [66.7%] and 10 females [33.3%]), age 19–65 years (average, 27.9 years). These include 24 cases of malignant melanoma (80.0%), 3 cases of melanocytoma (10.0%), 2 cases of diffuse melanocytosis (6.7%), and 1 case of unknown pathology (3.3%). Satellite nevi were reported in 25 cases (83.3%) and in 5 cases their presence was unknown (16.7%). Intracranial lesions were present in 28 cases (93.3%), and intraspinal lesions were present in 2 cases (6.7%). There are 4 cases of combined hydrocephalus (13.3%), and 2 cases of combined Dandy–Walker deformity (6.7%). Conclusions NCM is a rare disease, especially in adults. With the onset of symptoms, the diagnosis is generally confirmed. In children with congenital giant nevus, regular periodic surveys of the central nervous system (brain and spinal cord) with magnetic resonance imaging or cerebrospinal fluid analysis should be performed to diagnose NCM. Active treatment should be undertaken to improve the prognosis. [ABSTRACT FROM AUTHOR]