摘要:目的: 分析肝臟局灶性結節增生(FNH)的MRI表現和病理特點,探討兩者的相關性,提高FNH診斷的準確率。 方法 :回顧性分析23例(共28個病灶)經手術切除病理證實為FNH的MRI平掃及增強表現,與其病理特點進行對照。 結果 :25個病灶在平掃T1WI上呈等或稍低信號,T2WI上呈等或稍高信號,3個病灶在平掃T1WI及T2WI上均呈稍高信號,增強后所有28病灶動脈期可見明顯強化,門脈期及延遲期呈稍高、等或稍低信號,其中12個病灶可見中心纖維瘢痕延遲強化。FNH組織病理上表現為富血供的實質性腫塊,腫物內部組織較均勻,沒有異型細胞,中心可見纖維瘢痕。 結論 :肝臟MRI平掃及增強檢查能很好的反映FNH的組織病理及血供特點,能為FNH的診斷及鑒別診斷提供可靠證據。Abstract: Objective: To analyze the MRI manifestations and pathology characteristic of hepatic focal nodular hyperplasia(FNH),and to investigate their correlation. Methods : A retrospective analysis was made on the unenhanced and dynamic enhanced MR images of 23 patients (totally 28 lesions) with surgical and pathological proved FNH. Results :25 FNH lesions demonstrated isointensity or slightly hypointense on unenhanced T1WI,and isointensity or slightly hyperintense on unenhanced T2WI,3 FNH demonstrated hyperintense on both unenhanced T1WI and T2WI. 28 FNHs were markediyhyperintense in the arterial phase of dynamic contrast enhanced MRI, and isointense or slightly hyperintense in the portal and delayed phase．The seals were shown in 12 lesions, and enhanced in delayed phase．FNH is solid mass with vast blood supply,its inside structure is homogemeous. Typical seal can be found by microscopic examination．〖WTHZ〗Conclusion : MRI could disclose the pathologic features of FNH and its blood supply and improve the accuracy 0f its diagnosis．
OBJECTIVE:To investigate the diagnostic meaning of MRI in intraocular tumors.
METHODS:Forty-six cases of confirmed intraocular tumors,including choroidal melanoma(20 cases),retinoblastoma(18 cases),Coats disease(6 cases)and choroidal hemangioma(2 cases),were studied with MRI and compared with ultrasonography and CT.
RESULTS:In making discoveries about intraocular tumors,there were no sighificant difference between MRI and B-ultrasonography or CT （P＞0.03，chi;2=1.0716）while there were highly statistic sighificance in dediding characters and position （P＜0.01，deceding character chi;2=29.8314，positionchi;2=13.659）of them.
CONCLUSION:Among the examinations to find out about the position,character and secondary pathological insults of in traocular tumors MRI might be more available than CT and ultrasonography.
（Chin J Ocul Fundus Dis,1997,13:93-95 ）
The effect of deep brain stimulation (DBS) surgery treatment for Parkinson's disease is determined by the accuracy of the electrodes placement and localization. The subthalamic nuclei (STN) as the implant target is small and has no clear boundary on the images. In addition, the intra-operative magnetic resonance images (MRI) have such a low resolution that the artifacts of the electrodes impact the observation. The three-dimensional (3D) visualization of STN and other nuclei nearby is able to provide the surgeons with direct and accurate localizing information. In this study, pre- and intra-operative MRIs of the Parkinson's disease patients were used to realize the 3D visualization. After making a co-registration between the high-resolution pre-operative MRIs and the low-resolution intra-operative MRIs, we normalized the MRIs into a standard atlas space. We used a special threshold mask to search the lead trajectories in each axial slice. After checking the location of the electrode contacts with the coronal MRIs of the patients, we reconstructed the whole lead trajectories. Then the STN and other nuclei nearby in the standard atlas space were visualized with the grey images of the standard atlas, accomplishing the lead reconstruction and nerve nuclei visualization near STN of all patients. This study provides intuitive and quantitative information to identify the accuracy of the DBS electrode implantation, which could help decide the post-operative programming setting.
ObjectiveTo make the model of Wistar suckling rats Focal cortical dysplasia (FCD) by liquid nitrogen freezing brain cortex and verify it. Analysed the electroencephalogram (EEG) and magnetic resonance imaging (MRI) features of the FCD model, in order to provide theoretical and experimental basis for human FCD diagnosis and treatment.
MethodsTake the first day of Wistar suckling rats as experimental object, liquid nitrogen freezing Wistar suckling rats brain cortex.Make examination of EEG and MRI for Wistar suckling rats. The Brain tissue slice of Wistar suckling rats model dyed by HE and check with light microscope examination.
ResultsIn experiment group, the sample epileptic discharge rate of EEG was about 41.6% on average, and showed visible spike wave, spine slow wave frequency distribution. Experimental Wistar suckling rats MRI showed positive performance for long T1 and long T2 signal, brain tissue slices HE staining showed brain cortex layer structure and columnar structure disorder, exist abnormal neurons and the balloon sample cells.
ConclusionThe method of liquid nitrogen freezing Wistar suckling rats cortex can established FCDⅢd animal models successfully, and showed specific EEG and MRI, which has important value for diagnosis and treatment of human FCD.
ObjectiveTo analyse the seizure semeiology of MRI negative insular epilepsy.MethodsA case of patient with insular epilepsy who presented in Epileptic Center, Guangdong 999 Brain Hospital was collected. Related literatures were thoroughly reviewed.ResultsThe patient was diagnosised as insular epilepsy by SEEG and postoperative pathology reported focal cortical dysplasia Ib.ConclusionsThe insula lobe is a part of the limbic system, and the seizure semeiology in insular epilepsy is varied. Seizure semeiology analysis is particularly important in the evaluation of presurgical especially in a MRI negative case. In this paper, we summarized the semeiology characteristics of various parts of insula lobe, and provided some references for the diagnosis and treatment of insular epilepsy.
Coronary microcirculation dysfunction (CMVD) is an important risk factor for the prognosis of re-perfused ischemic heart. Recent studies showed that the evaluation of CMVD has significant impact on both the early diagnosis of heart diseases relevant to blood supply and prognosis after myocardial reperfusion. In this review, the definition of CMVD from the perspective of pathophysiology was clarified, the principles and features of the state-of-the-art imaging technologies for CMVD assessment were reviewed from the perspective of engineering and the further research direction was promoted.
Objective
The method of metabonomics based on nuclear magnetic resonance (NMR) imaging was used to explore the difference in metabolites of serum and bile, and to analyze the metabolic variation related to the pathogenesis of gallbladder stones between normal people/liver transplantation donors and patients with gallbladder stones.
Methods
Prospectively collected the serum samples (17 cases) and bile samples (19 cases) in 19 patients with gallbladder stones who underwent surgery in West China Hospital form March 2016 to December 2016, as well as the serum samples of 10 healthy persons and the bile samples of 15 liver transplantation donors at the same time period. The differences of metabolites in the blood and bile in these 3 groups were compared by using 1H-NMR metabonomics technology and chemometric methods.
Results
The concentrations of valine, alanine, lysine, glutamine, glutamate, pyruvate, creatinine, choline, alpha-glucose, beta-glucose, tyrosine, histidine, and hypoxanthine in serum of patients with gallbladder stones decreased significantly, comparing with those of healthy people without gallbladder stones (P<0.05), while 1, 2-propanediol, acetoacetate, and lactate increased significantly in the serum of patients with gallbladder stones (P<0.05). The concentrations of taurine conjugated bile acids, glycine conjugated bile acids, choline, and phosphatidylcholine decreased significantly in the bile of patients with gallbladder stones when compared with those of liver transplantation donors (P<0.05), while cholesterol increased significantly in the bile of patients with gallbladder stones (P<0.05).
Conclusions
There are significant differences of the serum and bile metabolites between patients with gallbladder stones and healthy men without gallbladder stones/liver transplantation donors. 1H-NMR metabonomics is helpful to investigate the pathogenesis of gallbladder stones.
When applying deep learning algorithms to magnetic resonance (MR) image segmentation, a large number of annotated images are required as data support. However, the specificity of MR images makes it difficult and costly to acquire large amounts of annotated image data. To reduce the dependence of MR image segmentation on a large amount of annotated data, this paper proposes a meta-learning U-shaped network (Meta-UNet) for few-shot MR image segmentation. Meta-UNet can use a small amount of annotated image data to complete the task of MR image segmentation and obtain good segmentation results. Meta-UNet improves U-Net by introducing dilated convolution, which can increase the receptive field of the model to improve the sensitivity to targets of different scales. We introduce the attention mechanism to improve the adaptability of the model to different scales. We introduce the meta-learning mechanism, and employ a composite loss function for well-supervised and effective bootstrapping of model training. We use the proposed Meta-UNet model to train on different segmentation tasks, and then use the trained model to evaluate on a new segmentation task, where the Meta-UNet model achieves high-precision segmentation of target images. Meta-UNet has a certain improvement in mean Dice similarity coefficient (DSC) compared with voxel morph network (VoxelMorph), data augmentation using learned transformations (DataAug) and label transfer network (LT-Net). Experiments show that the proposed method can effectively perform MR image segmentation using a small number of samples. It provides a reliable aid for clinical diagnosis and treatment.
癲癇患者大腦網絡的功能連接存在特異性改變。然而這種改變是疾病本身或是癲癇發作產生的結果尚不明確。研究為縱向研究，找對難治性顳葉癲癇患者（Temporal lobe epilepsy，TLE）手術前及術后發作得到控制后的標準認知功能網絡連接。該研究納入 17 例手術預后達到 Engel I 級的難治性 TLE 患者作為試驗組，同時納入 17 例匹配的正常受試者作為對照組。在手術前后使用經典認知任務以評估認知網絡的功能連接（含對照組），并使用嚴格的方法消除偽影。TLE 患者在術前與健康對照組相比，功能連接存在顯著差異，這種差異是廣泛而非唯一的，包括默認網絡以及顳葉/聽覺子網絡。然而，接受癲癇手術并且發作得到控制后患者的網絡連接并未得到明顯改善，術后功能網絡的異常與術前幾乎一致。研究結果提示，癲癇對大腦功能連接存在長期而持續的影響，當難治性 TLE 患者進行手術時（一般發生在首次診斷的數年后）此種改變已經不可逆轉。此結果對于頑固性癲癇的治療具有潛在的意義，提示延遲的手術治療可能控制癲癇發作，但不能逆轉疾病所導致的功能性大腦網絡改變。
Focus on the inconsistency of the shape, location and size of brain glioma, a dual-channel 3-dimensional (3D) densely connected network is proposed to automatically segment brain glioma tumor on magnetic resonance images. Our method is based on a 3D convolutional neural network frame, and two convolution kernel sizes are adopted in each channel to extract multi-scale features in different scales of receptive fields. Then we construct two densely connected blocks in each pathway for feature learning and transmission. Finally, the concatenation of two pathway features was sent to classification layer to classify central region voxels to segment brain tumor automatically. We train and test our model on open brain tumor segmentation challenge dataset, and we also compared our results with other models. Experimental results show that our algorithm can segment different tumor lesions more accurately. It has important application value in the clinical diagnosis and treatment of brain tumor diseases.
