OBJECTIVE: To investigate the clinical value of MRI modified water-lipid separation technique (mDIXON-Quant) in terms of T2* values and fat fraction (FF) values for evaluating the degree of cervical intervertebral disc degeneration. METHODS: A total of 118 patients who underwent routine MRI of the cervical vertebra and the mDIXON-Quant examination in Fuyang People's Hospital from March 2019 to January 2024 were collected. The T2* values of C2/3 to C6/7 intervertebral discs and FF values of the upper and lower vertebral bodies were measured. Cervical intervertebral disc degeneration was graded according to the Pfirrmann criteria. The T2* values and FF values of different patients were compared with the Pfirrmann grades, and the correlation between T2* values, FF values, and Pfirrmann grades was analyzed by Spearman correlation. RESULTS: The T2* values of cervical intervertebral discs in grades I, II, III, IV, and V all showed a decreasing trend ( P＜0.05). The decreasing order of FF values in the upper cervical vertebra was IV, V, III, II, and I ( F=93.28, P＜0.05), and the decreasing order of FF values in the lower cervical vertebra was IV, III, V, II, and I ( F=112.037, P＜0.05). Spearman correlation analysis showed that the T2* values of cervical intervertebral discs were negatively correlated with the Pfirrmann grades ( P＜0.05), and the FF values of the upper and lower vertebrae were positively correlated with the Pfirrmann grades ( P＜0.05). CONCLUSION The mDIXON-Quant technique can be used to quantify the T2* values and FF values of cervical intervertebral disc degeneration and plays an important role in accurate clinical diagnosis and evaluation of treatment effects.
Humans ; Intervertebral Disc Degeneration/diagnostic imaging* ; Cervical Vertebrae/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Male ; Female ; Middle Aged ; Adult ; Intervertebral Disc/diagnostic imaging* ; Lipids

After the production of the gradient coil of the magnetic resonance imaging system, electromagnetic field testing is required to verify whether the assembly accuracy meets the electromagnetic field requirements. Since the passive magnetic field B _z satisfies the Laplace ^,s equation and is a harmonic function, and according to the extreme value principle of harmonic function, the maximum or minimum values of B _z can only appear on the boundaries, so the observation points of the magnetic field are generally selected on the surface of the spherical imaging area. For superconducting magnets used for human body magnetic resonance imaging, a spherical area with a center diameter of 40~50 cm is generally selected as the shimming target area. Only the field value of the target area needs to be measured, and the spherical harmonic coefficients obtained after data processing are used to determine the magnetic field performance of the gradient coil. There are many testing principles and methods for electromagnetic fields, so there is no unified way and method in the field of commercial applications. This article is based on the Gauss-Legendre numerical integration, measures and analyzes the magnetic field performance of gradient coils by building a data acquisition system, and this article applies numerical analysis methods to calculate the spherical harmonic coefficients of the magnetic field using discrete test data, providing a feasible method for the production and testing of gradient coils.
Magnetic Resonance Imaging/methods* ; Magnetic Fields ; Electromagnetic Fields ; Equipment Design

OBJECTIVE: Evaluate the clinical application effect of low-field infant MRI. METHODS: Using literature review, expert consultation, and two rounds of Delphi to determine the evaluation index system. Then retrospectively analyze and compare the data of low-field infant MRI and high-field MRI from January 2023 to December 2024. RESULTS: There is a certain gap between low-field infant MRI and high-field MRI in terms of signal-to-noise ratio, image uniformity, software system reliability, scanning time, user interface friendliness and image result consistency. However, there was no difference in terms of spatial resolution and image quality. The noise, hardware system reliability, mean time between failure and the rate of examination completed without sedation are better than that of high-field MRI. CONCLUSION Low-field infant MRI meets needs of clinical diagnostic and has stable performance. It can be used as a routine screening tool for brain diseases near the bed.
Magnetic Resonance Imaging/methods* ; Humans ; Infant ; Retrospective Studies ; Signal-To-Noise Ratio ; Reproducibility of Results ; Brain Diseases/diagnostic imaging* ; Brain/diagnostic imaging* ; Software

OBJECTIVE: To elucidate how spinal manipulative therapy (SMT) exerts its analgesic effects through regulating brain function in lumbar disc herniation (LDH) patients by utilizing resting-state functional magnetic resonance imaging (rs-fMRI). METHODS: From September 2021 to September 2023, we enrolled LDH patients (LDH group, n=31) and age- and sex-matched healthy controls (HCs, n=28). LDH group underwent rs-fMRI at 2 distinct time points (TPs): prior to the initiation of SMT (TP1) and subsequent to the completion of the SMT sessions (TP2). SMT was administered once every other day for 30 min per session, totally 14 treatment sessions over a span of 4 weeks. HCs did not receive SMT treatment and underwent only one fMRI scan. Additionally, participants in LDH group completed clinical questionnaires on pain using the Visual Analog Scale (VAS) and the Japanese Orthopedic Association (JOA) score, whereas HCs did not undergo clinical scale assessments. The effects on the brain were jointly characterized using the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo). Correlation analyses were conducted between specific brain regions and clinical scales. RESULTS: Following SMT treatment, pain symptoms in LDH patients were notably alleviated and accompanied by evident activation of effects in the brain. In comparison to TP1, TP2 exhibited the most significant increase in ALFF values for Temporal_Sup_R and the most notable decrease in ALFF values for Paracentral_Lobule_L (voxelwise P<0.005; clusters >30; FDR correction). Additionally, the most substantial enhancement in ReHo values was observed for the Cuneus_R, while the most prominent reduction was noted for the Olfactory_R (voxelwise P<0.005; clusters >30; FDR correction). Moreover, a comparative analysis revealed that, in contrast to HCs, LDH patients at TP1 exhibited the most significant increase in ALFF values for Temporal_Pole_Sup_L and the most notable decrease in ALFF values for Frontal_Mid_L (voxelwise P<0.005; clusters >30; FDR correction). Furthermore, the most significant enhancement in ReHo values was observed for Postcentral_L, while the most prominent reduction was identified for ParaHippocampal_L (voxelwise P<0.005; clusters >30; FDR correction). Notably, correlation analysis with clinical scales revealed a robust positive correlation between the Cuneus_R score and the rate of change in the VAS score (r=0.9333, P<0.0001). CONCLUSIONS Long-term chronic lower back pain in patients with LDH manifests significant activation of the "AUN-DMN-S1-SAN" neural circuitry. The visual network, represented by the Cuneus_R, is highly likely to be a key brain network in which the analgesic efficacy of SMT becomes effective in treating LDH patients. (Trial registration No. NCT06277739).
Humans ; Magnetic Resonance Imaging ; Intervertebral Disc Displacement/diagnostic imaging* ; Male ; Female ; Brain/diagnostic imaging* ; Adult ; Manipulation, Spinal/methods* ; Middle Aged ; Lumbar Vertebrae/physiopathology* ; Pain Management ; Rest ; Case-Control Studies

Exosomes are small vesicles commonly found in bodily fluids such as blood, urine, ascites, and breast milk. As essential mediators of intercellular communication, exosomes play pivotal roles in physiological and pathological processes including material transport, signal transduction, homeostasis regulation, immune response, and angiogenesis. They are promising biomarkers for disease diagnosis and key carriers for therapeutic drug delivery. Longitudinal tracking of exosome biodistribution, elucidating their migratory routes and homing effects, determining optimal delivery routes and therapeutic dosages, and evaluating implantation in target tissues are crucial for better understanding their mechanisms of action and guiding clinical applications. Magnetic resonance imaging (MRI), as a non-invasive and repeatable imaging technique, offers an ideal approach for exosome tracking. By labeling exosomes with specific contrast agents or tracers and detecting them via MRI, researchers can trace exosomes in vivo. This facilitates advancements in exosome-based nanomedicine and accelerates the clinical translation of exosome diagnostics and therapeutics.
Exosomes/metabolism* ; Humans ; Magnetic Resonance Imaging/methods* ; Contrast Media ; Animals ; Tissue Distribution

OBJECTIVES: Patients with connective tissue diseases (CTD) have a high incidence of cardiac involvement, which often presents insidiously and can progress rapidly, making it one of the leading causes of death. Multiparametric cardiovascular magnetic resonance (CMR) provides a comprehensive quantitative evaluation of myocardial injury and is emerging as a valuable tool for detecting cardiac involvement in CTD. This study aims to investigate the correlations between CMR features and serological biomarkers in CTD patients, assess their potential clinical value, and further explore the impact of pre-CMR immunotherapy intensity on CMR-specific parameters, thereby evaluating the role of CMR in the early diagnosis of CTD-related cardiac involvement. METHODS: A retrospective analysis was conducted on 72 consecutive CTD patients who underwent CMR at Xiangya Hospital of Central South University between September 2019 and March 2024. Clinical data, serological markers, and CMR parameters were collected. Differences in CMR parameters were compared between CTD patients with positive and negative serological markers. Correlations between serological biomarkers and CMR parameters were analyzed, with subgroup analyses performed for different CTD subtypes. Logistic regression (univariate and multivariate) was applied to explore the effects of pre-CMR immunotherapy intensity on CMR parameters, and receiver operating characteristic (ROC) curve analysis was used to determine cutoff values. RESULTS: In differential analyses, CTD patients with elevated interleukin (IL)-1β and IL-6 levels exhibited significantly higher myocardial T₂ values compared with those with normal levels (P=0.014, P=0.012). Elevated IL-10 was associated with a higher prevalence of microvascular lesions on CMR (P=0.038). Correlation analysis revealed a significant positive association between high-sensitivity cardiac troponin T (hs-cTnT) and T₂ values (r=0.371, P=0.009). ROC analysis indicated that when the hs-cTnT threshold was 0.01 ng/mL, the sensitivity and specificity for predicting elevated left ventricular T₂ values were 85.71% and 61.11%, respectively [area under the curve (AUC)=0.767, P=0.001]. hs-cTnT and creatine kinase (CK) were also positively correlated with native T₁ values (r=0.371, P=0.009; r=0.364, P=0.032). Erythrocyte sedimentation rate (ESR) showed a positive correlation with the percentage of the late gadolinium enhancement (LGE) (r=0.236, P=0.047). Conversely, hs-cTnT correlated negatively with global radial strain (GRS) (r=-0.297, P=0.034), while CK correlated negatively with both GRS and global circumferential strain (GCS) (r=-0.292, P=0.022; r=-0.282, P=0.027). Among patients with elevated hs-cTnT, the cumulative glucocorticoid dose prior to CMR was negatively associated with elevated T₂ values (OR=0.997, P=0.018), and this correlation remained significant after adjusting for duration of steroid use (OR=0.997, P=0.044). ROC analysis showed that when the cumulative glucocorticoid dose did not exceed 613 mg/mL (prednisone equivalent), the sensitivity and specificity for predicting elevated T₂ values were 90.48% and 77.78%, respectively (AUC=0.862, P<0.001). CONCLUSIONS Several inflammatory biomarkers demonstrate correlations with specific CMR parameters, with hs-cTnT showing the strongest associations across multiple indices. Elevated hs-cTnT suggests a high likelihood of cardiac involvement in CTD patients. Furthermore, pre-CMR immunotherapy intensity significantly influences the specificity of T₂ mapping, indicating its importance in interpreting CMR results. These findings provide critical insights for clinicians in the early recognition, timely intervention, and disease evaluation. Future research should further explore the role of CMR in the assessment of CTD-related cardiac assessment of CTD-related cardiac involvement. Future studies should further explore the role of CMR in evaluating CTD cardiac manifestations and its integration with other clinical data to optimize patient management.
Humans ; Retrospective Studies ; Male ; Female ; Connective Tissue Diseases/blood* ; Middle Aged ; Adult ; Biomarkers/blood* ; Magnetic Resonance Imaging/methods* ; ROC Curve ; Interleukin-6/blood* ; Troponin T/blood*

Prostate cancer is the second most common cancer in men, accounting for 14.1% of new cancer cases in 2020. The aggressiveness of prostate cancer is highly variable, depending on its grade and stage at the time of diagnosis. Despite recent advances in prostate cancer treatment, some patients still experience recurrence or even progression after undergoing radical treatment. Accurate initial staging and monitoring for recurrence determine patient management, which in turn affect patient prognosis and survival. Classical imaging has limitations in the diagnosis and treatment of prostate cancer, but the use of novel molecular probes has improved the detection rate, specificity, and accuracy of prostate cancer detection. Molecular probe-based imaging modalities allow the visualization and quantitative measurement of biological processes at the molecular and cellular levels in living systems. An increased understanding of tumor biology of prostate cancer and the discovery of new tumor biomarkers have allowed the exploration of additional molecular probe targets. The development of novel ligands and advances in nano-based delivery technologies have accelerated the research and development of molecular probes. Here, we summarize the use of molecular probes in positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), optical imaging, and ultrasound imaging, and provide a brief overview of important target molecules in prostate cancer.
Humans ; Male ; Prostatic Neoplasms/diagnosis* ; Molecular Probes ; Molecular Imaging/methods* ; Magnetic Resonance Imaging ; Positron-Emission Tomography ; Tomography, Emission-Computed, Single-Photon ; Ultrasonography ; Optical Imaging ; Biomarkers, Tumor ; Precision Medicine/methods*

Objective:To exploring the value of MR neuroimaging for quantitative assessment of the facial nerve and peripheral lymph nodes in patients with acute peripheral facial paralysis. Methods:Based on a prospective experimental design, 32 patients with idiopathic peripheral facial palsy were enrolled in the experiment. Based on MR neuroimaging technology, MR high-resolution thin-layer images of bilateral facial nerves were acquired. The diameters of different segments of the bilateral facial nerve were measured, including the labyrinthine segment, the geniculate ganglion, the horizontal segment, the vertical segment, the stem-mammary foramen segment, the trunk of the parotid segment, the temporal trunk, and the cervical trunk, as well as the quantitative indicators of peri-auricular and parotid lymph nodes（number, length and diameter of the largest lymph nodes）. Differences in quantitative indices of nerve diameter and peripheral lymph nodes between the paraplegic and healthy sides were compared using the paired t-test and Wilcoxon signed rank test. Results:The diameter of geniculate ganglion, mastoid foramen stem, parotid main trunk, temporal facial trunk, and cervical facial trunk were notably increased on the facial paralysis side compared to the contralateral side（P<0.05）. However, no significant differences were observed in the diameter of labyrinthine segment, horizontal segment, or vertical segment compared to the contralateral side. There were significantly more periauricular lymph nodes on the facial paralysis side than the contralateral side（P=0.001）. Conclusion:MR neuroimaging enables the quantitative assessment of structural changes in the facial nerve of patients with acute peripheral facial paralysis, demonstrating nerve enlargement in the geniculate ganglion, stylomastoid foramen segment, main trunk of the parotid segment, temporal facial trunk, and cervical facial trunk. Additionally, an increased number of periauricular lymph nodes is observed on the affected side. These findings may aid clinicians in assessing the efficacy of treatments and predict the prognosis of these patients.
Humans ; Facial Nerve/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Prospective Studies ; Female ; Male ; Neuroimaging/methods* ; Lymph Nodes/diagnostic imaging* ; Facial Paralysis/diagnostic imaging* ; Adult ; Middle Aged

Objective:To explore the value of high resolution computed tomography（HRCT） combined with Magnetic Resonance Imaging（MRI） in the diagnosis of inner ear malformation. Methods:HRCT and MRI data of 82 patients with inner ear malformations were analyzed retrospectively. HRCT MPR and CPR reconstruction of the inner ear structure, facial nerve canal and oblique sagittal MRI reconstruction of the internal auditory canal were performed. The inner ear malformations were classified, the conditions of facial nerve canal and cochlear nerve were evaluated. The association between inner ear malformation and cochlear nerve dysplasia were analyzed by Chi-square test with continuity correction. Results:Among the 82 patients with inner ear malformations,there were 49 cases of bilateral symmetry, 11 cases of bilateral asymmetry and 22 cases of unilateral inner ear malformations. Respectively, the most prevalent types were IP-Ⅱ（42.96%）, dilatation of atrium aqueduct（18.31%） and malformations of atrium and semicircular canal 19.72%. Out of 50 cases of cochlear malformations,only 3 were isolated cochlear malformations, and the rest were accompanied by other malformations of varying degrees. In the 67 ears examined by MRI, 26（38.81%） had cochlear nerve deficiency（CND）, and the incidence of CND varied with different types of inner ear malformations. Out of 142 ears, 28（19.72%） had abnormalities of the facial nerve canal. Conclusion:HRCT combined with MRI can accurately distinguish the types of inner ear malformation and effectively evaluate the facial nerve canal and cochlear nerve, and further provides the important finger and Guide value for the clinician to formulate the reasonable treatment and the operation plan.
Humans ; Ear, Inner/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Retrospective Studies ; Female ; Male ; Tomography, X-Ray Computed/methods* ; Child ; Adolescent ; Adult ; Child, Preschool ; Cochlear Nerve/diagnostic imaging* ; Facial Nerve/abnormalities* ; Cochlea/abnormalities* ; Infant ; Young Adult

OBJECTIVES: To construct a bone tumor classification model based on feature decoupling and fusion for processing modality loss and fusing multimodal information to improve classification accuracy. METHODS: A decoupling completion module was designed to extract local and global bone tumor image features from available modalities. These features were then decomposed into shared and modality-specific features, which were used to complete the missing modality features, thereby reducing completion bias caused by modality differences. To address the challenge of modality differences that hinder multimodal information fusion, a cross-attention-based fusion module was introduced to enhance the model's ability to learn cross-modal information and fully integrate specific features, thereby improving the accuracy of bone tumor classification. RESULTS: The experiment was conducted using a bone tumor dataset collected from the Third Affiliated Hospital of Southern Medical University for training and testing. Among the 7 available modality combinations, the proposed method achieved an average AUC, accuracy, and specificity of 0.766, 0.621, and 0.793, respectively, which represent improvements of 2.6%, 3.5%, and 1.7% over existing methods for handling missing modalities. The best performance was observed when all the modalities were available, resulting in an AUC of 0.837, which still reached 0.826 even with MRI alone. CONCLUSIONS The proposed method can effectively handle missing modalities and successfully integrate multimodal information, and show robust performance in bone tumor classification under various complex missing modality scenarios.
Humans ; Bone Neoplasms/diagnosis* ; Multimodal Imaging/methods* ; Magnetic Resonance Imaging ; Tomography, X-Ray Computed ; Image Processing, Computer-Assisted/methods* ; Algorithms