Objective
To clarify relationship between signal heterogeneity on hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI and prognosis of hepatocellular carcinoma (HCC).
Methods
From January 2014 to January 2017 in the First Affiliated Hospital of Chongqing Medical University, a total of 77 patients with the pathologically proved HCC underwent Gd-EOB-DTPA-enhanced MRI prior to surgery were included in this study. On the basis of the signal heterogeneity in the hepatobiliary phase, the included patients were designed to homogeneous hypointensity group and heterogeneous hyperintensity group. The disease-free survival time were compared between the 2 groups and it’s influencing factors were analyzed.
Results
Seventy-seven patients with HCC were included, including 45 cases of homogeneous hypointensity and 32 cases of heterogeneous hyperintensity. There were no significant differences in the age, gender, etiology, liver function, alpha-fetoprotein, differentiated degree, Child-Pugh grade, lesion diameter, lesion border, and number of lesions between the 2 groups (P>0.05). However, the HCC patients with heterogeneous hyperintensity had a later BCLC staging (P=0.001). The disease-free survival time of the patients with homogeneous hypointensity and heterogeneous hyperintensity was (17.0±9.8) months and (12.4±10.4)months, respectively. The Kaplan-Meier survival curve showed that the disease-free survival time in the patients with homogeneous hypointensity was significantly better than that in the patients with heterogeneous hyperintensity (P=0.020). The results of univariate analysis showed that the other confounding factors had no effect on the disease-free survival time of patients with hepatocellular carcinoma (P>0.05) except for the signal of hepatobiliary phase (P<0.05). Furthermore, the hepatobiliary phase signal, BCLC stage, and degree of differentiation, which might be clinically considered as potentially influencing for the prognosis of patients with HCC, were included in the Cox multivariate proportional hazard regression model and found that the heterogeneous hyperintensity was still the risk factor of the disease-free survival rate in patients with HCC (P=0.047).
Conclusion
Signal heterogeneity on hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI is related to prognosis of patients with HCC, heterogeneous hyperintensity may indicate a lower disease-free survival rate.
ObjectiveTo summarize the application of magnetic resonance imaging (MRI) in the evaluation of pancreatic exocrine function.MethodIn this paper, we reviewed and summarized the related literatures about the application of MRI in the field of pancreatic exocrine function evaluation in recent years.ResultsA variety of MRI techniques could be used to detect the pancreatic exocrine function. In addition to conventional MRI techniques, there were also MRI stimulated by pancreatic secretions, cine (dynamic) cholangiopancreatography based on space selective reverse recovery pulse, and so on.ConclusionThe new MRI techniques have potential for semi-quantitative and quantitative evaluation of pancreatic exocrine function.
Right-sided cardiac valvular diseases have traditionally been considered less important than disease of mitral or aortic valve. However, severe tricuspid regurgitation could lead to right ventricle dysfunction and reduce patients' survival rate. In clinic setting, tricuspid valve disease should be paid more attention for patients with secondary tricuspid regurgitation caused by left-sided valvular surgery combined with irreversible annular dilatation increasing the risk of re-operation. In this review, we summarize the epidemiology, anatomy, pathology, diagnosis, ultrasound and cardiac magnetic resonance imaging findings in patients with tricuspid regurgitation.
ObjectiveTo investigate the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid enhanced magnetic resonance imaging (Gd-EOB-DTPA-MRI) in gross morphological classification of hepatocellular carcinoma (HCC). MethodsThe clinicopathologic data of patients with HCC who received surgical treatment in the Affiliated Huai’an Hospital of Xuzhou Medical University from January 2017 to December 2022 were retrospectively gathered. The Gd-EOB-DTPA-MRI was performed before operation. Two radiologists independently assessed the gross morphological classification of HCC according to the imaging performance. The tumors were cut into sections in a coronal plane and were taken pictures for recording pathological features after operation. The tumors were assigned into 4 types according to the references and clinical experiences: single nodular type (SN), single nodular with extranodular growth type (SN-EG), confluent multi-nodular type (CMN), and infiltration type (IF). Matching degree of morphological classification was analyzed between by the Gd-EOB-DTPA-MRI and resected specimen. The pathological features of 4 types of HCC were also analyzed. ResultsA total of 87 patients with HCC were included. The gross morphological classification by the Gd-EOB-DTPA-MRI was 28 (32.2%) patients with SN, 28 (32.2%) patients with SN-EG, 21 (24.1%) patients with CMN, 10 (11.5%) patients with IF, which by the resected specimen was 33 (37.9%) patients with SN, 24 (27.6%) patients with SN-EG, 21 (24.1%) patients with CMN, and 9 (10.4%) patients with IF in the 87 patients with HCC. The Kappa’s coefficient of agreement between the results of Gd-EOB-DTPA-MRI and postoperative resection specimens was 0.776 (P=0.199). There were statistical differences in the tumor diameter and microvascular invasion (MVI) among the 4 types of gross morphology classification (F=2.937, P=0.038; χ2=16.852, P=0.001), the MVI rate was highest and tumor diameter was biggest in the patients with IF among the 4 types of gross morphology classification (P<0.05). ConclusionsFrom the results of this study, the gross morphological classification of HCC is closely related to the tumor diameter and MVI. Results of Gd-EOB-DTPA-MRI and postoperative resection specimens in assessing the gross morphological classification are good agreement. Therefore, an accurate preoperative planning and better therapy strategy for the patients with HCC can be provided according to gross morphological classification by preoperative Gd-EOB-DTPA-MRI.
Objective
To evaluate the imaging features of hepatic epithelioid hemangioendothelioma (HEHE).
Methods
The imaging data of 15 patients with HEHE proved by surgery and pathology who reeived treatment in West China Hospital from Jul. 2012 to Aug. 2018, were retrospectively analyzed. The location, boundary, density/signal, and enhanced features of tumor were observed.
Results
Among 15 cases, there were 3 cases of single, 5 cases of multiple, and 6 cases of fusion. Thirteen cases were distributed under the capsular of liver, accompanied by the capsule retraction sign, 14 cases had lollipop sign, 7 cases had core pattern sign. On plain CT images, the lesions manifested as low density. On plain MR images, the lesions had hypointense on T1-weighted images and hyperintense on T2-weighted images. The enhanced scanning could be characterized by mild enhancement, rim-like enhancement at early phase, and progressive centripetal fill-in enhancement during dynamic phase imaging.
Conclusions
CT and MRI imagings of HEHE are different, and there are certain characteristics of capsule retraction sign, lollipop sign, and core pattern sign.
Pulsed magnetic field gradients generated by gradient coils are widely used in signal location in magnetic resonance imaging (MRI). However, gradient coils can also induce eddy currents in final magnetic field in the nearby conducting structures which lead to distortion and artifact in images, misguiding clinical diagnosis. We tried in our laboratory to measure the magnetic field of gradient-induced eddy current in 1.5 T superconducting magnetic resonance imaging device; and extracted key parameters including amplitude and time constant of exponential terms according to inductance-resistance series mathematical module. These parameters of both self-induced component and crossing component are useful to design digital filters to implement pulse pre-emphasize to reshape the waveform. A measure device that is a basement equipped with phantoms and receiving coils was designed and placed in the isocenter of the magnetic field. By applying testing sequence, contrast experiments were carried out in a superconducting magnet before and after eddy current compensation. Sets of one dimension signal were obtained as raw data to calculate gradient-induced eddy currents. Curve fitting by least squares method was also done to match inductance-resistance series module. The results also illustrated that pulse pre-emphasize measurement with digital filter was correct and effective in reducing eddy current effect. Pre-emphasize waveform was developed based on system function. The usefulness of pre-emphasize measurement in reducing eddy current was confirmed and the improvement was also presented. All these are valuable for reducing artifact in magnetic resonance imaging device.
To solve the problem of precise positioning of carp brain tissue coordinates, it is proposed in this paper for a method for transforming the coordinates of magnetic resonance imaging of carp brain tissue into the coordinates of electrode implantation using a brain stereotaxic apparatus. In this study, the 3.0T magnetic resonance imaging instrument was used to scan the carp brain. We independently established the three-dimensional positioning coordinate system of the brain, the three-dimensional coordinate assistance system of skull surface and the three-dimensional coordinate assistance system in brain tissue. After two coordinate transformations, the magnetic resonance image coordinates of the brain electrodes implantation sites were converted into the three-dimensional stereotactic coordinate system to guide the electrodes implantation. The experimental groups were divided into two groups, A and B. Group A was the group of magnetic resonance imaging apparatus combining with the brain stereotaxic apparatus, and group B was the group of brain atlas combining with the brain stereotaxic apparatus. Each group had 20 tails of carps (n = 20). This two methods were used to implant the electrodes into the cerebellar motor area. The underwater experiments of the carp robots were carried out to test the two methods. The results showed that the accuracy of the implanted electrodes were 90% in group A and 60% in group B. The success rate of group A was significantly higher than that of group B (P < 0.05). Therefore, the new method in this paper can accurately determine the coordinates of carp brain tissue.
Objective To observe the characteristics of magnetic resonance diffusion tensor imaging（MR-DTI）for optic nerves and optic radiation in blind patients.Methods The optic nerves and optic radiation of 20 blind patients（blind group）and 20 controls（control group） were scanned by MR-DTI. Fractional anisotropy (FA) and directional encoded color (DEC) maps were acquired through postprocessing with the aid of volumeone 1.72 software. The signal intensity of optic nerves and optic radiation were then observed. The FA, mean diffusivity (MD), lambda;∥ and lambda;perp; value of bilateral optic nerves and optic radiation in two groups were measured in the DEC maps.Results While the high signal intensity was found in bilateral optic nerves in FA and DEC maps in control group，the signal decreased markedly in the blind group. The FA and lambda;∥ value of optic nerves in the blind group were declined obviously compared to that in the control group. The difference was statistically significant (t=16.294, 14.660;P=0.000). The MD and lambda;perp; value of optic nerves in the blind group were increased obviously compared to that in the control group, the difference was also statistically significant (t=8.096, 8.538; P=0.000). The high signal intensity was found in bilateral optic radiation in FA and DEC maps in both the blind and control groups. There were no statistic differences in FA and MD value in bilateral optic radiation between the blind and control groups (Left：t=1.456，1.811；P=0.152，0.076. Right：t=0.779，0.073；P=0.440，0.942). Conclusion A low signal intensity of bilateral optic nerves and a high signal intensity of bilateral optic radiation were found in blind patients.
ObjectiveTo help junior radiologists and surgeons better interpret MRI images of rectal cancer.MethodThe guidelines, expert consensus and research progress on the application of MR imaging in rectal cancer in recent years were reviewed.ResultsRectal MR had the ability to accurately evaluate a number of important findings that may impact patient’ management, including distance of the tumor to the mesorectal fascia, presence of extramural vascular invasion, and presence of lymph nodes.ConclusionsRectal MRI is an important basis for clinical staging and multidisciplinary diagnosis and treatment of rectal cancer. Surgeons and radiologists must master the key imaging anatomical basis and clinical practice points in order to accurately interpret the image information of MRI in rectal cancer.
ObjectiveSeizure-related respiratory or cardiac dysfunction was once thought to be the direct cause of sudden unexpected death in epilepsy (SUDEP), but both may be secondary to postictal cerebral inhibition. An important issue that has not been explored to date is the neural network basis of cerebral inhibition. Our aim was to investigate the features of neural networks in patients at high risk for SUDEP using a blood oxygen level-dependent (BOLD) resting-state functional MRI (Rs-fMRI) technique.
MethodsRs-fMRI data were recorded from 13 patients at high risk for SUDEP and 12 patients at low risk for SUDEP. The amplitude of low-frequency fluctuations (ALFF) values were compared between the two groups to decipt the regional brain activities.
ResultsCompared with patients at low risk for SUDEP, patients at high risk exhibited significant ALFF reductions in the right superior frontal gyrus, the left superior orbital frontal gyrus, the left insula and the left thalamus; and ALFF increase in the right middle cigulum gyrus, the right supplementary motor area and the left thalamus.
ConclusionsThese findings highlight the need to understand the fundamental neural network dysfunction in SUDEP, which may fill the missing link between seizure-related cardiorespiratory dysfunction and SUDEP, and provide a promising neuroimaging biomarker for risk prediction of SUDEP.
