Diffusion tensor imaging (DTI) is a rapid development technology in recent years of magnetic resonance imaging. The diffusion tensor interpolation is a very important procedure in DTI image processing. The traditional spectral quaternion interpolation method revises the direction of the interpolation tensor and can preserve tensors anisotropy, but the method does not revise the size of tensors. The present study puts forward an improved spectral quaternion interpolation method on the basis of traditional spectral quaternion interpolation. Firstly, we decomposed diffusion tensors with the direction of tensors being represented by quaternion. Then we revised the size and direction of the tensor respectively according to different situations. Finally, we acquired the tensor of interpolation point by calculating the weighted average. We compared the improved method with the spectral quaternion method and the Log-Euclidean method by the simulation data and the real data. The results showed that the improved method could not only keep the monotonicity of the fractional anisotropy (FA) and the determinant of tensors, but also preserve the tensor anisotropy at the same time. In conclusion, the improved method provides a kind of important interpolation method for diffusion tensor image processing.
Magnetic resonance imaging(MRI) can obtain multi-modal images with different contrast, which provides rich information for clinical diagnosis. However, some contrast images are not scanned or the quality of the acquired images cannot meet the diagnostic requirements due to the difficulty of patient's cooperation or the limitation of scanning conditions. Image synthesis techniques have become a method to compensate for such image deficiencies. In recent years, deep learning has been widely used in the field of MRI synthesis. In this paper, a synthesis network based on multi-modal fusion is proposed, which firstly uses a feature encoder to encode the features of multiple unimodal images separately, and then fuses the features of different modal images through a feature fusion module, and finally generates the target modal image. The similarity measure between the target image and the predicted image in the network is improved by introducing a dynamic weighted combined loss function based on the spatial domain and K-space domain. After experimental validation and quantitative comparison, the multi-modal fusion deep learning network proposed in this paper can effectively synthesize high-quality MRI fluid-attenuated inversion recovery (FLAIR) images. In summary, the method proposed in this paper can reduce MRI scanning time of the patient, as well as solve the clinical problem of missing FLAIR images or image quality that is difficult to meet diagnostic requirements.
ObjectiveTo summarize the research progress of near infra-red fluorescence imaging (NIRFI) in biliary tract surgery, and to provide protection for improvements of therapeutic effect and safety of biliary tract surgery.MethodThe relevant literatures about studies on NIRFI in the biliary tract surgery in recent years were reviewed.ResultsThe NIRFI had been preliminarily used in the surgical treatment of benign and malignant biliary diseases, and had shown its unique value in cholangiography. It provided a new method for effectively avoiding surgical complications, shortening operation time, reducing the rate of conversion to open surgery, evaluating blood supply of bile duct and improving the safety of operation.ConclusionsNIRFI has achieved notable successes in treatment of biliary tract diseases. With future application of fluorescence imaging in near infra-red Ⅱ window and new specific fluorescence targeting molecules, this technique will highlight its more important values in biliary surgery.
ObjectiveTo analyze the causes of unrelieved epilepsy thoroughly in children with isolated focal cortical dysplasia (FCD) based on MRI.MethodsRetrospective analysis of MRI and clinical data of 21 children with isolated FCD during July 2014 to January 2018, which confirmed by pathology and unrelieved thoroughly after operation performed, the pathological types and MRI signs were analyzed, as well as the frequency of different MRI signs in FCD of each pathological type. Analyzed the possible factors of surgical failure.ResultsAmong the 21 cases, there were 15 males and 6 females, with an average age of (5.7±0.3) years and an average course of disease of (3.4±0.5) years.MRI signs of this part of the children were mainly manifested by blurred focal gray matter boundaries, abnormal cortical structure changes (thickening and/or thinning), transmantle signs (abnormal cone signals extending from subcortical white matter to the ventricle) and abnormal gray matter signals, which were similar to MRI signs of FCD with satisfactory postoperative epilepsy control. 17 cases (80.9%) appeared epileptic discharge after operation in the EEG monitoring area 2 weeks to 6 months, FCD type I and type Ⅱ accounted for 35.3%, 64.7% respectively. During intraoperative EEG monitoring, no epileptiform discharge was observed in the transmantle sign region in 6 cases, and the region was retained, and only the surrounding abnormal discharge cortex was removed, complete removal of the tansmantle sign and surrounding abnormal discharge area was performed in 2 cases, and different degrees of epileptic epilepsy were observed in both methods.ConclusionMRI signs of isolated FCD with unrelieved epilepsy after operation were nonspecific, there were still epilepsy of varying degrees after all epileptogenic lesions have been removed, the cause may be related to potential epileptic factors.
ObjectiveTo preliminarily evaluate the feasibility of ultra-wide-angle fundus imaging (UWFI) to observe the Weiss ring (vitreous floats) and the effectiveness and safety of neodymium-doped yttrium aluminum garnet (Nd: YAG) laser ablation in the treatment of symptomatic Weiss ring. MethodsA retrospective clinical study. From March 2016 to December 2019, 80 eyes of 68 patients with symptomatic Weiss ring who were diagnosed and treated at Guangzhou Aier Eye Hospital were included in the study. Among them, there were 39 eyes in 32 males and 41 eyes in 36 females; the average age was 53.7±10.8 years old. All the affected eyes were examined by slit lamp microscope combined with 90 D front lens and UWFI. The position and shape of the vitreous floating objects by drawing pictures were recorded. All the affected eyes underwent Nd: YAG laser ablation treatment. Three months after treatment, a questionnaire survey was conducted on the patients to assess the improvement of subjective symptoms. Those with a total score of 10, 7-9, 3-6, and ≤2 points were defined as cured, significant improvement, partial improvement, and no improvement, respectively. The measurement software Gauge 1.0 was used to manually measure the long diameter, circumference and area of the vitreous float on the UWFI image. The diameter of the optic disc to 1 Unit (U) was set as a standardized reference value. Those who did not show UWFI and no floating objects were found on the front mirror were recorded as 0. The changes of vitreous floats before and after treatment were compared by Wilcoxon rank sum test; the changes in their size before and after treatment and the patients' subjective symptom improvement scores after treatment were analyzed by Spearman rank correlation. ResultsAfter treatment, in 80 eyes, there were no vitreous floats in 59 eyes (73.8%, 59/80) on UWFI. Before treatment, the circumference of the vitreous float was 1.84 (1.07, 2.64) U, the long diameter was 1.17 (0.84, 1.66) U, and the area was 0.18 (0.08, 0.30) U2; after treatment, the circumference was 0.00 (0.00, 0.23) U, The long diameter is 0.00 (0.00, 0.23) U, and the area was 0.00 (0.00, 0.01) U2. There were statistically significant differences in the perimeter, diameter, and area of floating objects before and after treatment (Z=?7.722, ?7.560, ?7.655; P＜0.001). The results of the questionnaire survey showed that the patient's subjective symptoms were cured, significantly improved, and partially improved in 49 (61.3%, 49/80), 25 (31.2%, 25/80), and 6 (7.5%, 6/80) eyes, respectively. The results of correlation analysis showed that the degree of improvement of the patient's subjective symptoms was related to the circumference (r=0.812), long diameter (r=0.796), and area (r=0.791) of the vitreous float on UWFI before and after treatment (P＜0.01). During the follow-up period, no complications such as increased intraocular pressure or decreased vision occurred. ConclusionsUWFI can objectively image the Weiss ring, and its size can be quantified relatively to the measurement software. Nd: YAG laser ablation treatment of symptomatic Weiss ring is safe and effective.
ObjectiveTo investigate the efficacy of vagus nerve stimulation (VNS) in patients with refractory magnetic resonance imaging (MRI)-negative epilepsy and to evaluate potential clinical predictors. MethodsA retrospective collection of efficacy data was conducted on 24 patients with intractable MRI-negative epilepsy treated with VNS, who were followed up for more than six months, at Beijing Tiantan Hospital and Beijing Fengtai Hospital from January 2016 to September 2023. Patients were divided into two subgroups based on their response to VNS: responders (≥50% reduction in seizure frequency) and non-responders (<50% reduction in seizure frequency). The relationship between preoperative clinical data and VNS efficacy was further analyzed to identify potential predictors of VNS efficacy. ResultsA total of 24 patients were included, with an average age of (14.26±8.39) years old. Seizure frequency was reduced by more than 50% in 37.5% of patients, and 8.3% of patients achieved seizure-free after VNS treatment. Preoperative seizure frequency and interictal epileptiform discharge type were significantly associated with VNS efficacy (P<0.05). Multivariate regression analysis showed that a monthly seizure frequency of less than 100 and focal interictal epileptiform discharges were independent predictors of VNS efficacy (P<0.05). ConclusionVNS is an effective treatment for patients with refractory MRI-negative epilepsy. Lower monthly seizure frequency and focal interictal epileptiform discharges are potential predictors of VNS efficacy. These findings provide important references for clinicians in selecting and evaluating patients for VNS treatment.
Intrahepatic ectopic splenosis is rare and lacks typical clinical and imaging features. We analyzed the clinical, pathological, and imaging characteristics of a patient with intrahepatic ectopic splenosis admitted to the Guangzhou First People’s Hospital in combining with literature review. The aim of case analysis is to enhance comprehension of the disease and provide a reference for clinical doctors in diagnosis.
ObjectiveTo investigative current status and hotspot issues of pancreatic cancer imaging research.MethodsThe literatures focusing on pancreatic cancer and published from 2001 to 2020 were retrieved from the core database of Web of Science. The quantitative analysis of literatures was then conducted by using the CiteSpace software based on the bibliometric method. The research trend was then summarized systematically and the potential research fronts and focuses were explored.ResultsA total of 2111 articles in the field of pancreatic cancer imaging research were retrieved. The clustering of co-citation of pancreatic cancer included vascular resection, irreversible electroporation, autoimmune pancreatitis, sporadic pancreatic cancer, sarcopenia, pancreas, stereotactic body radiation therapy, metastatic pancreatic cancer, familial pancreatic cancer, abdominal ultrasonography, fibroblast, early diagnosis, time trends in survival, radiomics, pancreatitis, gemcitabine, concurrent chemoradiotherapy, adjuvant chemotherapy, and microbubbles. The burst keywords in the field of pancreatic cancer after 2016 included FOLFIRINOX, skeletal muscle, sarcopenia, and texture analysis. The hot keywords clustering had prognosis, fine needle aspiration, positron emission tomography, vascular invasion, angiogenesis, unresectable, liver transplant, extend pancreatectomy, transplantation, paclitaxel, metastatic colorectal cancer, colorectal cancer, microsatellite stable, radiomics, hospital volume, occult metastasis, risk factor.ConclusionIt might be the trend of imaging research to study the prognosis, risk factors, and quantitative sarcopenia of pancreatic cancer by using radiomics.
The cardiac conduction system (CCS) is a set of specialized myocardial pathways that spontaneously generate and conduct impulses transmitting throughout the heart, and causing the coordinated contractions of all parts of the heart. A comprehensive understanding of the anatomical characteristics of the CCS in the heart is the basis of studying cardiac electrophysiology and treating conduction-related diseases. It is also the key of avoiding damage to the CCS during open heart surgery. How to identify and locate the CCS has always been a hot topic in researches. Here, we review the histological imaging methods of the CCS and the specific molecular markers, as well as the exploration for localization and visualization of the CCS. We especially put emphasis on the clinical application prospects and the future development directions of non-destructive imaging technology and real-time localization methods of the CCS that have emerged in recent years.
In this study we performed Tissue Doppler Imaging (TDI), two-dimensional speckle tracking imaging (2D-STI) and three-dimensional speckle tracking imaging (3D-STI) on enrolled healthy, overweight and obese groups (34 subjects in each group), respectively, to analyze cardiac structure and its function. Compared with healthy group, global longitudinal strain (GLS), global circumferential strain (GCS), global area strain(GAS) and global radial strain (GRS) decreased progressively (P＜0.05). The ratio of early diastolic mitral inflow velocity to global early diastolic strain rate of left ventricle (E/e′sr) (r=0.466, P＜0.001), GLS(r=0.502, P＜0.001), GCS(r=0.426, P＜0.001), GAS(r=0.535, P＜0.001) and GRS(r=-0.554, P＜0.001) were correlated with body mass index (BMI). E/e′sr (r=0.37, P=0.003), GLS(r=0.455, P＜0.001), GCS(r=0.282, P=0.02), GAS(r=0.412, P＜0.001) and GRS (r=-0.471, P＜0.001) were correlated with free fatty acid (FFA). Stepwise multiple linear regression revealed that BMI was independently correlated with E/e′sr, GLS, GCS, GAS and GRS. Waist to hip ratio (WHR) was independently correlated with GLS, GCS, GAS and GRS. FFA was independently correlated with E/e′sr(P＜0.05). The study showed that cardiac structure changed and impaired left ventricular global systolic and diastolic function in overweight and obes population. Moreover, BMI, WHR and FFA may be independent influence factors of cardiac function in overweight and obese population.
