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1.
Int. braz. j. urol ; 48(2): 294-302, March-Apr. 2022. tab, graf
Article in English | LILACS | ID: biblio-1364942

ABSTRACT

ABSTRACT Objective: To compare enhancement patterns of typical adrenal adenomas, lipid-poor adenomas, and non-adenomas on magnetic resonance imaging (MRI). Materials and Methods: Evaluation of adrenal nodules larger than 1.0 cm, with at least 2-year follow-up, evaluated on MRI in January 2007 and December 2016. Two different protocols were included - upper abdomen MRI (delayed phase after 3 minutes) and abdomen and pelvis MRI (delayed phase after 7 minutes) - and nodules were divided in typical adenomas (characterized on out-of-phase MRI sequence), lipid-poor adenomas (based on follow-up imaging stability) and non-adenomas (based on pathological finding or follow-up imaging). T2-weighted and enhancement features were analyzed (absolute and relative washout and enhancement curve pattern), similarly to classic computed tomography equations. Results: Final cohort was composed of 123 nodules in 116 patients (mean diameter of 1.8 cm and mean follow up time of 4 years and 3 months). Of them, 98 (79%) nodules had features of typical adenomas by quantitative chemical shift imaging, and demonstrated type 3 curve pattern in 77%, mean absolute and relative washout of 29% and 16%, respectively. Size, oncologic history and T2-weighted features showed statistically significant differences among groups. Also, a threshold greater than 11.75% for absolute washout on MRI achieved sensitivity of 71.4% and specificity of 70.0%, in differentiating typical adenomas from non-adenomas. Conclusion: Calculating absolute washout of adrenal nodules on MRI may help identifying proportion of non-adenomas.


Subject(s)
Humans , Adrenal Gland Neoplasms/pathology , Adrenal Gland Neoplasms/diagnostic imaging , Magnetic Resonance Imaging/methods , Tomography, X-Ray Computed/methods , Retrospective Studies , Sensitivity and Specificity , Contrast Media , Diagnosis, Differential
2.
Article in Chinese | WPRIM | ID: wpr-936259

ABSTRACT

Objective: The characteristics of 3D-FLAIR MRI images of the inner ear of patients with vestibular neuritis were preliminarily studied to explore the possible pathogenesis of vestibular neuritis, and the correlation analysis was conducted in combination with vestibular function to provide a basis for accurate diagnosis of vestibular neuritis. Methods: A total of 36 patients with vestibular neuritis (VN) from December 2019 to October 2020 were collected from the Vertigo Department of Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University. There were 36 cases (18 females, 18 males) with unilateral acute vestibular neuritis, 17 cases of left ear and 19 cases of right ear. According to the results of 3D-FLAIR MRI in the inner ears, the patients were divided into the enhanced group and the non-enhanced group (the health side served as the normal control group). The results of vestibular function examination in the two groups were compared. SPSS19.0 software was used for statistical processing to analyze the relationship between the vestibular function and the characteristics of 3D-FLAIR imaging in the inner ears. Results: Abnormal enhancement of 3D-FLAIR was found in 31 cases (86.1%) of the 36 cases, including 14 cases of both vestibular nerve and vestibular terminal organ enhancement, eight cases of superior vestibular nerve enhancement alone, seven cases of vestibular terminal organ enhancement alone, and two cases of cochlear enhancement alone. Observation of abnormal reinforcement of vestibular nerve showed: twenty-one cases of superior vestibular nerve reinforcement, one case of superior and inferior vestibular nerve reinforcement. No abnormalities were found in 3D-FLAIR of inner ear in 5 cases. According to the analysis of vestibular function results, there were 19 cases (52.8%) with total vestibular involvement, sixteen cases (44.4%) with superior vestibular involvement alone, and one case (2.8%) with inferior vestibular involvement alone. Comparison of vestibular function between the five cases (non-enhancement group) and the 31 cases (enhanced group) in the 3D-FLAIR group of the inner ears showed that the CP values of caloric tests in the enhanced group were higher (60.81±3.49 vs 34.12±7.37), with statistically significant difference (t=-2.898, P<0.01). Conclusion: In patients with vestibular neuritis, 3D-FLAIR MRI scan of the inner ear provides visual imaging evidence for clinical practice, considering that the lesion site of vestibular neuritis is not only in the vestibular nerve, but also in the vestibular end organ. Patients with 3D-FLAIR enhanced in the inner ear may have more significant vestibular function damage.


Subject(s)
Caloric Tests , Female , Humans , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Male , Vestibular Neuronitis/diagnosis , Vestibule, Labyrinth
3.
Article in Chinese | WPRIM | ID: wpr-936069

ABSTRACT

Objective: To construct a prediction model of pathologic complete response (pCR) in locally advanced rectal cancer patients who received programmed cell death protein-1 (PD-1) antibody and total neoadjuvant chemoradiotherapy by using radiomics based on MR imaging data and to investigate its predictive value. Methods: A clinical diagnostic test study was carried out. Clinicopathalogical and radiological data of 38 patients with middle-low rectal cancer who received PD-1 antibody combined with total neoadjuvant chemoradiotherapy and underwent TME surgery from January 2019 to September 2021 in our hospital were retrospectively collected. Among 38 patients, 23 were males and 15 were females with a median age of 68 (47-79) years and 13 (34.2%) a chieved pCR. These 38 patients were stratified and randomly divided into the training group (n=26) and test group (n=12) for modeling. All the patients underwent rectal MRI before treatment. The clinical, imaging and radiomics features of all the patients were collected, and the clinical feature model and radiomics model were constructed. The receiver operating characteristic (ROC) curves of each model were drawn, and the constructed model was evaluated through the area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value and negative predictive value. Results: There were no significant differences in age, gender, primary location of tumor and postoperative pathology between the two groups (all P>0.05). Forty-one features were extracted from region of interest in each modality, including 9 first-order features, 24 gray level co-occurrence matrix features and 8 shape features. From 38 patients, 41 features were extracted from each imaging modality of baseline and preoperative DWI and T2WI images, totally 164 features. Only 4 features were preserved after correlation analysis between each pair of features and t-test between pCR and non-pCR subjects. After LASSO cross validation, only the first-order skewness of the baseline DWI image before treatment and the volume in the baseline T2WI image before treatment were retained. The area under the curve, sensitivity, specificity, positive and negative predictive values of the prediction model established by applying these two features in the training group and the test group were 0.856 and 0.844, 77.8% and 100.0%, 88.2% and 75.0%, 77.8% and 66.7%, 88.2% and 100.0%, respectively. The decision curve analysis of the radiomics model showed that the strategy of this model in predicting pCR was better than that in treating all the patients as pCR and that in treating all the patients as non-pCR. Conclusion: The pCR prediction model for rectal cancer patients receiving PD-1 antibody combined with total neoadjuvant radiochemotherapy based on MRI radiomics has the potential to be used in clinical screening or rectal cancer patients who can be spared from radical surgery.


Subject(s)
Aged , Antibodies/therapeutic use , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Neoadjuvant Therapy/methods , Programmed Cell Death 1 Receptor , Rectal Neoplasms/therapy , Retrospective Studies
4.
Article in Chinese | WPRIM | ID: wpr-941035

ABSTRACT

OBJECTIVE@#To propose a multi-modality-based super-resolution synthesis model for reconstruction of routine brain magnetic resonance images (MRI) with a low resolution and a high thickness into high-resolution images.@*METHODS@#Based on real paired low-high resolution MRI data (2D T1, 2D T2 FLAIR and 3D T1), a structure-constrained image mapping network was used to extract important features from the images with different modalities including the whole T1 and subcortical regions of T2 FLAIR to reconstruct T1 images with higher resolutions. The gray scale intensity and structural similarities between the super-resolution images and high-resolution images were used to enhance the reconstruction performance. We used the anatomical information acquired from segment maps of the super-resolution T1 image and the ground truth by a segmentation tool as a significant constraint for adaptive learning of the intrinsic tissue structure characteristics of the brain to improve the reconstruction performance of the model.@*RESULTS@#Our method showed the performance on the testing dataset than other methods with an average PSNR of 33.11 and SSIM of 0.996. The anatomical structure of the brain including the sulcus, gyrus, and subcortex were all reconstructed clearly using the proposed method, which also greatly enhanced the precision of MSCSR for brain volume measurement.@*CONCLUSION@#The proposed MSCSR model shows excellent performance for reconstructing super-resolution brain MR images based on the information of brain tissue structure and multimodality MR images.


Subject(s)
Brain/pathology , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods
5.
Chinese Journal of Cardiology ; (12): 570-576, 2022.
Article in Chinese | WPRIM | ID: wpr-940890

ABSTRACT

Objective: To observe the effect of lipid regulating therapy on carotid atherosclerotic plaque in diabetic patients. Methods: The REACH study, conducted between March 2009 and February 2012, enrolled asymptomatic patients with magnetic resonance imaging (MRI) confirmed carotid atherosclerotic plaque, who had never taken lipid-lowering drugs. Patients were treated with a moderate dose of rosuvastatin for 24 months. Blood lipid levels were measured and carotid MRI was performed at baseline, 3 and 24 months after treatment. The volume of carotid wall and lipid-rich necrotic core (LRNC) were measured by image analysis software. This study retrospectively analyzed patients in the REACH study. Patients were divided into diabetes group and non-diabetic group. The changes of blood lipid level and MRI parameters of carotid atherosclerotic plaque were compared between the two groups and their correlation was analyzed. Results: A total of 38 patients with carotid atherosclerotic plaque were included in this study, including 13 patients (34.2%) in the diabetic group and 25 patients (65.8%) in the non-diabetic group. Baseline parameters were comparable between the two groups, except higher HbA1c level in diabetes group (P<0.05). Compared with baseline, the total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and triglyceride (TG) levels were significantly decreased at 3 and 24 months in both two groups (P<0.05). The change of high-density lipoprotein cholesterol (HDL-C) in diabetes group was not obvious, while it was significantly increased in non-diabetic group at 24 months ((1.38±0.33) mmol/l vs. (1.26±0.26) mmol/l, P<0.05). MRI results showed that the volume and percentage of LRNC remained unchanged at 3 months, slightly decreased at 24 months (64.86 (45.37, 134.56) mm3 vs. 75.76 (48.20, 115.64) mm3, P>0.05) and (15.84% (11.47%, 24.85%) vs. 16.95% (11.64%, 22.91%), P>0.05) in diabetic group. In non-diabetic group, the volume and percentage of LRNC were significantly decreased at 3 months (63.01 (44.25, 188.64) mm3 vs. 72.49 (51.91, 199.59) mm3, P<0.05) and (13.76% (8.81%, 27.64%) vs. 16.04% (11.18%, 27.05%), P<0.05) respectively. Both parameters further decreased to (55.63 (27.18, 179.40) mm3) and (12.71% (8.39%, 24.41%)) at 24 months (both P<0.05). Wall volume, lumen volume and percent wall volume (PWV) were not affected post therapy in both two groups(P>0.05). There were no correlations between the changes of plaque parameters including volume and percentage of LRNC, wall volume, lumen volume, PWV and the changes of blood lipid parameters (TC, LDL-C, HDL-C and TG) in 3 and 24 months (P>0.05). Conclusion: Lipid-lowering therapy possesses different effects on carotid atherosclerotic plaque in diabetic and non-diabetic patients, and the LRNC improvement is more significant in non-diabetic patients as compared to diabetic patients.


Subject(s)
Carotid Arteries/pathology , Carotid Artery Diseases/drug therapy , Cholesterol, HDL/therapeutic use , Cholesterol, LDL , Diabetes Mellitus , Humans , Magnetic Resonance Imaging/methods , Necrosis/pathology , Plaque, Atherosclerotic/drug therapy , Retrospective Studies , Rosuvastatin Calcium/therapeutic use
6.
Article in Chinese | WPRIM | ID: wpr-939610

ABSTRACT

Glioma is a primary brain tumor with high incidence rate. High-grade gliomas (HGG) are those with the highest degree of malignancy and the lowest degree of survival. Surgical resection and postoperative adjuvant chemoradiotherapy are often used in clinical treatment, so accurate segmentation of tumor-related areas is of great significance for the treatment of patients. In order to improve the segmentation accuracy of HGG, this paper proposes a multi-modal glioma semantic segmentation network with multi-scale feature extraction and multi-attention fusion mechanism. The main contributions are, (1) Multi-scale residual structures were used to extract features from multi-modal gliomas magnetic resonance imaging (MRI); (2) Two types of attention modules were used for features aggregating in channel and spatial; (3) In order to improve the segmentation performance of the whole network, the branch classifier was constructed using ensemble learning strategy to adjust and correct the classification results of the backbone classifier. The experimental results showed that the Dice coefficient values of the proposed segmentation method in this article were 0.909 7, 0.877 3 and 0.839 6 for whole tumor, tumor core and enhanced tumor respectively, and the segmentation results had good boundary continuity in the three-dimensional direction. Therefore, the proposed semantic segmentation network has good segmentation performance for high-grade gliomas lesions.


Subject(s)
Attention , Glioma/diagnostic imaging , Humans , Magnetic Resonance Imaging/methods , Semantics
7.
Article in Chinese | WPRIM | ID: wpr-935811

ABSTRACT

Objective: To explore the CT and MRI imaging findings of diquat toxic encephalopathy. Methods: CT and MRI imaging features of 10 patients with diquat poisoning encephalopathy who had been clinically diagnosed were retrospectively reviewed. Results: CT was performed in all 10 patients, and MRI was performed in 8 patients. In 10 patients, 7 had positive signs on CT, and 8 patients with MRI examination had abnormal changes in the images. The main CT findings were symmetrical hypodensity in bilateral cerebellar hemisphere, brainstem, thalamus and basal ganglia, and swelling of brain tissue. The main MRI findings were symmetrical lesions and brain edema in the deep nuclei of cerebellar hemisphere, brainstem, thalamus and basal ganglia, low signal on T1WI, high signal on T2WI and T2-FLAIR, and cytotoxic edema on diffusion weighted imaging (DWI) . On review after treatment, both CT and MRI showed resorption of the lesion, which narrowed in size. Conclusion: The imaging findings of diquat poisoning encephalopathy are characteristic and the location of the lesion is characteristic, and CT and MRI have a certain diagnostic value in diquat poisoning encephalopathy, which is important for clinical treatment.


Subject(s)
Brain Diseases , Diffusion Magnetic Resonance Imaging/methods , Diquat , Humans , Magnetic Resonance Imaging/methods , Neurotoxicity Syndromes/etiology , Retrospective Studies
8.
Journal of Integrative Medicine ; (12): 237-243, 2022.
Article in English | WPRIM | ID: wpr-929224

ABSTRACT

OBJECTIVE@#To investigate the changes in the functional connectivity (FC) in the right insula between migraine without aura (MWoA) and healthy controls by using resting-state functional magnetic resonance imaging (rs-fMRI), and to observe the instant alteration of FC in MWoA during electroacupuncture (EA) stimulation at Shuaigu (GB8).@*METHODS@#A total of 30 patients with MWoA (PM group) and 30 healthy controls (HC group) underwent rs-fMRI scans. The PM group underwent a second rs-fMRI scan while receiving EA at GB8. The right insula subregions, including the ventral anterior insula (vAI), dorsal anterior insula (dAI) and posterior insula (PI), were selected as the seed points for FC analysis.@*RESULTS@#Aberrant FC, including dAI with right postcentral gyrus, PI with left precuneus, was found among PM before EA (PMa), PM during EA (PMb) and HC. Meanwhile, decreased FC between dAI and the right postcentral gyrus was found in the PMa compared to the HC and PMb. Increased FC between the PI and left precuneus was found in the PMa compared to the HC and PMb. Correlation analysis showed that the FC value of the right postcentral gyrus in PMa was negatively correlated with the scores of Hamilton Rating Scale for Depression and Hamilton Rating Scale for Anxiety. The FC value of the left precuneus in PMa was positively correlated with the visual analogue scale score.@*CONCLUSION@#The alteration of FC between the right insula subregions and multiple brain regions may be an important index for MWoA. EA at GB8 was able to adjust the FC between the right insula subregions and parietal lobe, namely, the right dAI and right postcentral gyrus, and the right PI and left precuneus, thereby rendering an instant effect in the management of MWoA.


Subject(s)
Brain/diagnostic imaging , Electroacupuncture , Humans , Magnetic Resonance Imaging/methods , Migraine without Aura
9.
Neuroscience Bulletin ; (6): 519-532, 2022.
Article in English | WPRIM | ID: wpr-929106

ABSTRACT

Functional hubs with disproportionately extensive connectivities play a crucial role in global information integration in human brain networks. However, most resting-state functional magnetic resonance imaging (R-fMRI) studies have identified functional hubs by examining spontaneous fluctuations of the blood oxygen level-dependent signal within a typical low-frequency band (e.g., 0.01-0.08 Hz or 0.01-0.1 Hz). Little is known about how the spatial distributions of functional hubs depend on frequency bands of interest. Here, we used repeatedly measured R-fMRI data from 53 healthy young adults and a degree centrality analysis to identify voxelwise frequency-resolved functional hubs and further examined their test-retest reliability across two sessions. We showed that a wide-range frequency band (0.01-0.24 Hz) accessible with a typical sampling rate (fsample = 0.5 Hz) could be classified into three frequency bands with distinct patterns, namely, low-frequency (LF, 0.01-0.06 Hz), middle-frequency (MF, 0.06-0.16 Hz), and high-frequency (HF, 0.16-0.24 Hz) bands. The functional hubs were mainly located in the medial and lateral frontal and parietal cortices in the LF band, and in the medial prefrontal cortex, superior temporal gyrus, parahippocampal gyrus, amygdala, and several cerebellar regions in the MF and HF bands. These hub regions exhibited fair to good test-retest reliability, regardless of the frequency band. The presence of the three frequency bands was well replicated using an independent R-fMRI dataset from 45 healthy young adults. Our findings demonstrate reliable frequency-resolved functional connectivity hubs in three categories, thus providing insights into the frequency-specific connectome organization in healthy and disordered brains.


Subject(s)
Brain/diagnostic imaging , Connectome/methods , Humans , Magnetic Resonance Imaging/methods , Reproducibility of Results , Rest , Young Adult
10.
Article in Chinese | WPRIM | ID: wpr-929074

ABSTRACT

OBJECTIVE@#To investigate the value of quantitative synthetic magnetic resonance imaging (SyMRI) in distinguishing between benign and malignant breast lesions.@*METHODS@#We retrospectively collected data of preoperative conventional MRI and multi-dynamic multi-echo sequences from 95 patients with breast lesions showing mass-type enhancement on DCE-MRI, including 27 patients with benign lesions and 68 with malignant lesions. The MRI features of the lesions (shape, margin, internal enhancement pattern, time-signal intensity curve, and T2WI signal) were analyzed, and for each lesion, SyMRI-generated quantitative parameters including T1 and T2 relaxation time and proton density (PD) were measured before and after enhancement and recorded as T1p, T2p, PDp and T1e, T2e, and PDe, respectively. The relative change rate of each parameter was calculated. Logistic regression and all-subset regression analyses were performed for variable selection to construct diagnostic models of the breast lesions, and receiver-operating characteristic (ROC) analysis was used to assess the performance of each model for differentiation of benign and malignant lesions.@*RESULTS@#There were significant differences in the MRI features between benign and malignant lesions (P < 0.05). All the SyMRI-generated quantitative parameters, with the exception of T2e and Pdp, showed significant differences between benign and malignant lesions (P < 0.05). Among the constructed diagnostic models, the model based on all the DCE-MRI features combined with SyMRI parameters T2p and T1e (DCE-MRI+T2p+T1e) showed the best performance in the differential diagnosis malignant breast masses with an AUC of 0.995 (95% CI: 0.983-1.000).@*CONCLUSION@#Quantitative SyMRI can be used for differential diagnosis of benign and malignant breast lesions.


Subject(s)
Breast/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Contrast Media , Diagnosis, Differential , Female , Humans , Magnetic Resonance Imaging/methods , ROC Curve , Retrospective Studies
11.
Article in English | WPRIM | ID: wpr-928561

ABSTRACT

In recent years, magnetic resonance imaging (MRI) has been widely used in evaluating neonatal brain development, diagnosing neonatal brain injury, and predicting neurodevelopmental prognosis. Based on current research evidence and clinical experience in China and overseas, the Neonatologist Society of Chinese Medical Doctor Association has developed a consensus on the indications and standardized clinical process of neonatal brain MRI. The consensus has the following main points. (1) Brain MRI should be performed for neonates suspected of hypoxic-ischemic encephalopathy, intracranial infection, stroke and unexplained convulsions; brain MRI is not considered a routine in the management of preterm infants, but it should be performed for further evaluation when cranial ultrasound finds evidence of brain injury; as for extremely preterm or extremely low birth weight infants without abnormal ultrasound findings, it is recommended that they should undergo MRI examination at term equivalent age once. (2) Neonates should undergo MRI examination in a non-sedated state if possible. (3) During MRI examination, vital signs should be closely monitored to ensure safety; the necessity of MRI examination should be strictly evaluated for critically ill neonates, and magnetic resonance compatible incubator and ventilator can be used. (4) At present, 1.5 T or 3.0 T equipment can be used for neonatal brain MRI examination, and the special coil for the neonatal head should be used to improve signal-to-noise ratio; routine neonatal brain MRI sequences should at least include axial T1 weighted image (T1WI), axial T2 weighted imaging (T2WI), diffusion-weighted imaging, and sagittal T1WI or T2WI. (5) It is recommended to use a structured and graded reporting system, and reports by at least two reviewers and multi-center collaboration are recommended to increase the reliability of the report.


Subject(s)
Brain/pathology , Consensus , Humans , Hypoxia-Ischemia, Brain/pathology , Infant , Infant, Newborn , Infant, Premature , Magnetic Resonance Imaging/methods , Reproducibility of Results
12.
Article in Chinese | WPRIM | ID: wpr-928302

ABSTRACT

OBJECTIVE@#Based on the anatomical differences between discoid lateral meniscus(DLM) and normal lateral meniscus (NLM), this study aims to setting up the ultrasound examination parameters to distinguish DLM and NLM and explore the diagnostic value of these parameters on DLM.@*METHODS@#According to the inclusion, exclusion and matching criteria, 66 DLM patients(DLM group) and 132 NLM patients with other knee joint diseases(NLM group), hospitalized from October 2019 to June 2020, were included in this study. There were 18 males and 48 females in the DLM group, ranging in age from 3 to 60 years old, with a mean of (36.9±12.1) years old;36 males and 96 females in the NLM group, ranging in age from 3 to 60 years old, with a mean of (40.0±12.2) years old. Philips high frequency(3.0 to 12.0 MHz) linear array ultrasound probe was used to examine the lateral meniscus of all patients in two groups. Nine parameters including the thickness, width and the included angle of the anterior angle, body and posterior angle respectively in the lateral meniscus were measured. The included angke is formed by the chords of the upper and lower curved surfaces of the meniscus at the free edge. The independent t test was used to analyze the difference of the measured parameters between the DLM group and the NLM group. The receiver operating characteristic(ROC) curve was used to evaluate the cut-off value of each parameter for diagnosing DLM and the corresponding sensitivity, specificity, positive predictive value, negative predictive value, and area under the ROC curve(AUC).@*RESULTS@#The above 9 ultrasound measurement parameters between the DLM group and the NLM group had significant statistical differences(P<0.001). The ROC curve analysis method evaluated the cut-off value and diagnostic capabilities of these nine ultrasound parameters for DLM. The results showed that the cut-off value of the included angle of anterior part, body and posterior part were 25.85°, 24.85° and 29.15 °, respectively;and the sensitivity, specificity, negative predictive value, positive predictive value and AUC were significantly higher than other parameters, which were 88%, 91%, 79%, 95%, 0.94;89%, 94%, 82%, 97%, 0.96; 92%, 97%, 86%, 98%, 0.97, respectively.@*CONCLUSION@#Ultrasound diagnosis of DLM is feasible and reliable. The diagnostic ability of the included angle of the anterior part, body and posterior part in the lateral meniscus measured by ultrasound to diagnose DLM are significantly better than other ultrasound measurement parameters, and the sensitivity and specificity of those parameters are close to MRI. Therefore, ultrasound can be used as a reliable method for preliminary diagnosis of DLM.


Subject(s)
Adolescent , Adult , Child , Child, Preschool , Female , Humans , Knee Joint/diagnostic imaging , Magnetic Resonance Imaging/methods , Male , Menisci, Tibial/diagnostic imaging , Middle Aged , Osteoarthritis, Knee , Ultrasonography , Young Adult
13.
Article in Chinese | WPRIM | ID: wpr-928237

ABSTRACT

This study aims to explore the potential of polyaspartic acid grafted dopamine copolymer (PAsp- g-DA) chelated Fe 3+ for magnetic resonance imaging (MRI) visual photothermal therapy. Polyaspartic acid grafted copolymer of covalently grafted dopamine and polyethylene glycol (PAsp- g-DA/PEG) was obtained by the ammonolysis reaction of poly succinimide (PSI), and then chelated with Fe 3+ in aqueous solution. The relaxivity in vitro, magnetic resonance imaging enhancement in vivo and photothermal conversion effect at 808 nm were investigated. The results showed that polymeric iron coordination had good near-infrared absorption and photothermal conversion properties, good magnetic resonance enhancement effect, and good longitudinal relaxation efficiency under different magnetic field intensities. In summary, this study provides a new magnetic resonance visual photothermal therapeutic agent and a new research idea for the research in related fields.


Subject(s)
Dopamine , Magnetic Resonance Imaging/methods , Nanoparticles , Peptides , Phototherapy , Photothermal Therapy , Polymers
14.
Article in Chinese | WPRIM | ID: wpr-928219

ABSTRACT

Brain functional network changes over time along with the process of brain development, disease, and aging. However, most of the available measurements for evaluation of the difference (or similarity) between the individual brain functional networks are for charactering static networks, which do not work with the dynamic characteristics of the brain networks that typically involve a long-span and large-scale evolution over the time. The current study proposes an index for measuring the similarity of dynamic brain networks, named as dynamic network similarity (DNS). It measures the similarity by combining the "evolutional" and "structural" properties of the dynamic network. Four sets of simulated dynamic networks with different evolutional and structural properties (varying amplitude of changes, trend of changes, distribution of connectivity strength, range of connectivity strength) were generated to validate the performance of DNS. In addition, real world imaging datasets, acquired from 13 stroke patients who were treated by transcranial direct current stimulation (tDCS), were used to further validate the proposed method and compared with the traditional similarity measurements that were developed for static network similarity. The results showed that DNS was significantly correlated with the varying amplitude of changes, trend of changes, distribution of connectivity strength and range of connectivity strength of the dynamic networks. DNS was able to appropriately measure the significant similarity of the dynamics of network changes over the time for the patients before and after the tDCS treatments. However, the traditional methods failed, which showed significantly differences between the data before and after the tDCS treatments. The experiment results demonstrate that DNS may robustly measure the similarity of evolutional and structural properties of dynamic networks. The new method appears to be superior to the traditional methods in that the new one is capable of assessing the temporal similarity of dynamic functional imaging data.


Subject(s)
Aging/physiology , Brain/physiology , Brain Mapping , Humans , Magnetic Resonance Imaging/methods , Nerve Net/physiology , Transcranial Direct Current Stimulation/methods
15.
Article in Chinese | WPRIM | ID: wpr-927864

ABSTRACT

Objective To investigate the clinical and magnetic resonance imaging(MRI) manifestations of Rosai-Dorfman disease(RDD) in central nervous system. Method The clinical and MRI data of 5 cases of RDD in central nervous system confirmed by pathology in the PLA General Hospital were analyzed retrospectively. Results The 5 cases included 4 males and 1 female,aged(39.8±21.7) years on average.Among them,4 cases were located in the intracranial area and 1 case in the thoracic spinal canal.The lesion showed isointense signal on T1 weighted image and iso,slight-hypo,and slight-hyperintense signals on T2 weighted image,and it presented intensively homogeneous enhancement in contrast-enhanced MRI.Two cases showed compressed brain area with edema around the left parietal and left frontotemporal dura,thickening and enhancement in the adjacent dura,and dural tail sign.Three cases presented bone destruction in adjacent diploe and thoracic vertebrae.One case showcased slight-hypo perfusion of the left parietal dura in arterial spin labeling. Conclusions RDD lesion usually appears as iso,slight hypo and slight hyper-intense signals on T2 weighted image and presents intensively homogeneous enhancement in contrast-enhanced MRI.The disease may involve the adjacent bone and the lesion shows slight hypo-perfusion on perfusion images.The MRI manifestations of RDD are characteristic,which are helpful for preoperative diagnosis and evaluation of RDD.


Subject(s)
Central Nervous System/pathology , Female , Head , Histiocytosis, Sinus/pathology , Humans , Magnetic Resonance Imaging/methods , Male , Retrospective Studies
16.
Article in Chinese | WPRIM | ID: wpr-927855

ABSTRACT

Radiomics can extract high-throughput and quantitative image features from medical images and mine the information related to the pathophysiology of tumors,which can help clinical decision-making and improve the diagnostic and predictive performance.Radiomics has been widely used in the study of prostate cancer (PCa),demonstrating application values in the diagnosis and differential diagnosis,pathology classification,invasion assessment,efficacy prediction,and prognosis analysis of PCa.Here we reviewed the recent research progress of magnetic resonance imaging-based radiomics in PCa.


Subject(s)
Humans , Magnetic Resonance Imaging/methods , Male , Prognosis , Prostatic Neoplasms/pathology
17.
Article in Chinese | WPRIM | ID: wpr-927847

ABSTRACT

Objective To investigate the correlations of diffusion weighted imaging (DWI) with pathological grading,typing and clinical staging of cervical adenocarcinoma. Methods The data of 95 patients with cervical adenocarcinoma from May 2011 to February 2018 in Cancer Hospital Chinese Academy of Medical Sciences were collected for retrospective analysis.Before treatment,conventional MRI and DWI (b=0,800 s/mm2) were performed,and the apparent diffusion coefficient (ADC) value of cervical adenocarcinoma was measured.The ADC values were compared among different pathological grades,types,and clinical stages. Results The mean ADC value was (1.00±0.25)×10-3 mm2/s in the poorly differentiation group,(1.09±0.25)×10-3 mm2/s in the moderately differentiation group,and (1.22±0.20)×10-3 mm2/s in the well differentiation group,which showed significant difference between the poorly and well differentiation groups (P=0.002).The mean ADC values were (1.04±0.24) ×10-3 mm2/s and (1.21±0.26)×10-3 mm2/s in the endocervical adenocarcinoma (usual type) group and mucinous carcinoma group,respectively,which showed significant difference (P=0.005). Conclusions The worse differentiation of cervical adenocarcinoma corresponded to the lower ADC value.The ADC value of mucinous carcinoma was higher than that of endocervical adenocarcinoma (usual type).


Subject(s)
Adenocarcinoma/pathology , Diffusion Magnetic Resonance Imaging/methods , Female , Humans , Magnetic Resonance Imaging/methods , Retrospective Studies , Uterine Cervical Neoplasms/diagnostic imaging
18.
Chinese Medical Journal ; (24): 532-546, 2022.
Article in English | WPRIM | ID: wpr-927530

ABSTRACT

For the detection of steatosis, quantitative ultrasound imaging techniques have achieved great progress in past years. Magnetic resonance imaging proton density fat fraction is currently the most accurate test to detect hepatic steatosis. Some blood biomarkers correlate with non-alcoholic steatohepatitis, but the accuracy is modest. Regarding liver fibrosis, liver stiffness measurement by transient elastography (TE) has high accuracy and is widely used across the world. Magnetic resonance elastography is marginally better than TE but is limited by its cost and availability. Several blood biomarkers of fibrosis have been used in clinical trials and hold promise for selecting patients for treatment and monitoring treatment response. This article reviews new developments in the non-invasive assessment of non-alcoholic fatty liver disease (NAFLD). Accumulating evidence suggests that various non-invasive tests can be used to diagnose NAFLD, assess its severity, and predict the prognosis. Further studies are needed to determine the role of the tests as monitoring tools. We cannot overemphasize the importance of context in selecting appropriate tests.


Subject(s)
Elasticity Imaging Techniques/methods , Humans , Liver/pathology , Liver Cirrhosis/pathology , Magnetic Resonance Imaging/methods , Non-alcoholic Fatty Liver Disease
19.
Chinese Medical Journal ; (24): 591-597, 2022.
Article in English | WPRIM | ID: wpr-927512

ABSTRACT

BACKGROUND@#Insufficient cerebral perfusion is suggested to play a role in the development of Alzheimer disease (AD). However, there is a lack of direct evidence indicating whether hypoperfusion causes or aggravates AD pathology. We investigated the effect of chronic cerebral hypoperfusion on AD-related pathology in humans.@*METHODS@#We enrolled a group of cognitively normal patients (median age: 64 years) with unilateral chronic cerebral hypoperfusion. Regions of interest with the most pronounced hypoperfusion changes were chosen in the hypoperfused region and were then mirrored in the contralateral hemisphere to create a control region with normal perfusion. 11C-Pittsburgh compound-positron emission tomography standard uptake ratios and brain atrophy indices were calculated from the computed tomography images of each patient.@*RESULTS@#The median age of the 10 participants, consisting of 4 males and 6 females, was 64 years (47-76 years). We found that there were no differences in standard uptake ratios of the cortex (volume of interest [VOI]: P = 0.721, region of interest [ROI]: P = 0.241) and grey/white ratio (VOI: P = 0.333, ROI: P = 0.445) and brain atrophy indices (Bicaudate, Bifrontal, Evans, Cella, Cella media, and Ventricular index, P > 0.05) between the hypoperfused regions and contralateral normally perfused regions in patients with unilateral chronic cerebral hypoperfusion.@*CONCLUSION@#Our findings suggest that chronic hypoperfusion due to large vessel stenosis may not directly induce cerebral β-amyloid deposition and neurodegeneration in humans.


Subject(s)
Aged , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Arteries , Atrophy , Brain/metabolism , Cerebral Cortex/metabolism , Cerebrovascular Circulation , Constriction, Pathologic/pathology , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Positron-Emission Tomography/methods
20.
Article in Chinese | WPRIM | ID: wpr-927389

ABSTRACT

OBJECTIVE@#To explore the modulation of transcutaneous auricular vagus nerve stimulation (taVNS) on default mode network (DMN) in patients with primary insomnia (PI).@*METHODS@#A total of 22 PI patients (one patient dropped off and two patients were excluded) were included and treated with taVNS. The bilateral auricular points of Xin (CO15) and Shen (CO10) were selected and treated with disperse-dense wave at frequency of 4 Hz/20 Hz, the intensity was based on the patient's tolerance. taVNS was given once in the morning and once in the evening for 30 minutes each time. The treatment lasted for at least 5 days a week for 4 weeks. At the same time, 16 healthy subjects matched with gender and age were recruited. The Pittsburgh sleep quality index (PSQI) score was evaluated before and after treatment in PI patients. The resting-state functional magnetic resonance imaging (rs-fMRI) data of PI patients before and after treatment and healthy subjects at baseline period were collected to observe the effect of taVNS on the functional connection (FC) between posterior cingulate cortex (PCC) and whole brain.@*RESULTS@#After treatment, the total score of PSQI in PI patients was lower than that before treatment (P<0.01). Compared with healthy subjects, the FC of the left PCC was increased either with the left orbital superior frontal gyrus or with left middle frontal gyrus (P<0.001), and the FC between right PCC and left middle frontal gyrus was increased in PI patients before treatment (P<0.001). Compared before treatment, the FC between left PCC and left middle frontal gyrus was decreased (P<0.05), and the FC of the right PCC was decreased either with the right medial prefrontal cortex or with the left middle frontal gyrus in PI patients after treatment (P<0.001, P<0.01).@*CONCLUSION@#taVNS can modulate the FC between anterior and posterior DMN, and between DMN and cognitive control network of PI patients, which may be one of the brain effect mechanisms of taVNS in the treatment of PI patients.


Subject(s)
Brain/physiology , Default Mode Network , Humans , Magnetic Resonance Imaging/methods , Sleep Initiation and Maintenance Disorders/therapy , Vagus Nerve , Vagus Nerve Stimulation/methods
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