Peripheral carcinoma of the lung in magnetic resonance imaging

This study shows magnetic resonance imaging (MRI) to be a technique in the comprehensive diagnosis of peripheral carcinoma of the lung and in the determination of the extent of a tumor process in the chest. The paper specifies and systematizes the MRI signs of peripheral carcinoma of the lung, the signs of tumor invasion into the pleura, chest, and mediastinal structures. It also analyzes additional capacities of contrast enhancement.     

Anterior mediastinal paraganglioma: A case for preoperative embolization

ABSTRACT: BACKGROUND: Paraganglioma is a rare but highly vascular tumor of the anterior mediastinum. Surgical resection is a challenge owing to the close proximity to vital structures including heart, trachea and great vessels. Preoperative embolization has been reported once to facilitate surgical treatment. CASE PRESENTATION: We report a case of anterior mediastinal paraganglioma that was embolized preoperatively and was resected without the need for cardiopulmonary bypass and without major bleeding complications. CONCLUSION: We make a case to further the role of preoperative embolization in the treatment of mediastinal paragangliomas.     

Treatment of total sternal necrosis using the latissimus dorsi muscle flap

Complications after a median sternotomy incision, which is used currently in most cardiac and mediastinal surgical procedures, although infrequent, are serious. If sternal dehiscence follows median sternotomy, infection extends to vital underlying structures, exposing the anterior part of the heart and ascending aorta. Permanent hemorrhage, septic thrombosis, or septic perforation of prosthetic material demand soft-tissue coverage. In 5 patients with total sternum necrosis the retrosternal space was covered with a latissimus dorsi muscle flap in order to achieve stable protection of the exposed mediastinal organs.     

中国数字化可视人体鞍上池的横断面解剖与CT、MRI对照研究

目的:探讨鞍上池在中国数字化可视人体(Chinese visible human,CVH)与CT、MRI上的横断面解剖形态学表现。方法:选择做64层螺旋CT和MRI头部检查的健康志愿者各60例,获得5mm层厚横断面图像。从第2例中国数字化可视人体数据集中选取与CT、MRI相对应层面的头部薄层连续横断面标本图像,对照观察鞍上池在CVH、MRI与CT图像上的正常解剖形态、毗邻及内部结构。结果:CVH图像上,鞍上池表现为六角形和五角形两种形状。CVH薄层横断面图像能连续、清晰地显示鞍上池的正常形态、毗邻及内部结构。60例CT及MRI图像上,鞍上池全部显示,但解剖结构均不及CVH清晰。鞍上池在CT、MRI横断面图像上形状变化更大,以六角形最多,五角形次之,四角形最少,相应毗邻及内部结构也有所不同。六角形鞍上池在CVH、CT、MRI上有良好的对应关系,五角形鞍上池部分相匹配,CVH图像上无四角形鞍上池。结论:通过与CT、MRI进行对照研究,中国数字化可视人体能为颅脑疾病的影像识别和诊断提供断层解剖学依据。     

A case of cardiac sarcoidosis mimicking Brugada syndrome

A 17-year-old boy was admitted for management of ventricular fibrillation (VF) with intermittent Brugada pattern on ECG. On evaluation, cardiac MRI revealed myocardial scar and mediastinal lymphadenopathy. 18-Fluorodeoxyglucose positron emission tomography scan showed inflammation in the heart, lungs, and lymph nodes. He was diagnosed as a case of cardiac sarcoidosis (CS) and treated with steroids. However, there was a reactivation of cardiac inflammation and the development of a second VF storm. Following catheter ablation, the patient's arrhythmia improved. This report highlights the inflammation due to CS mimicking channelopathic features.     

Mediastinal pancreatic pseudocyst--a case report and review of the literature

Pancreatic pseudocyst, a common complication of acute or chronic pancreatitis, in rare instances may also extend to the mediastinum. A case of 67-year-old woman presenting with a triad of chest pain, dysphagia, and dyspnea is presented. The patient had an episode of acute alcoholic pancreatitis 1 year before presentation. Chest radiography on admission showed a retrocardiac opacity. Two-dimensional echocardiography revealed an echolucent mass compressing the left atrium. A subsequent upper gastrointestinal series for her dysphagia showed extrinsic compression of the distal esophagus. Finally a definitive diagnosis was made with computed tomography (scan), which revealed a 19 x 12 cm pseudocyst extending from the body of pancreas into the thorax and compressing the esophagus and the cardiac chambers. A mediastinal pseudocyst can cause symptoms due to compression or invasion of surrounding structures. The fluid collection may enlarge slowly and hence the symptoms can be delayed as in our patient. The pseudocyst was successfully treated using endoscopic ultrasound-guided transesophageal drainage. Approximately 50 cases of mediastinal extension of the pancreatic pseudocyst in the world literature are reported. At this time, this is only the second time that successful drainage of a mediastinal pseudocyst using a transesophageal approach under endoscopic ultrasound guidance has been reported. The literature was reviewed for clinical presentation, complications, and available treatment options for mediastinal pancreatic pseudocysts.     

X-ray and magnetic resonance stereotaxy for functional and nonfunctional neurosurgery

By means of new plastic stereotactic ring and head fixers, stereotactic procedures can be combined with MRI, with stereotactic coordinates obtained from the MRI images. The method was rechecked against CT stereotaxy and shows a good correspondence of the target coordinates. With MRI stereotaxy, structures near bony regions will be more accessible than with CT stereotaxy. Moreover, the MRI procedure seems to have advantages for functional therapy without the necessity of contrast ventriculography.     

Quantitative Measurements in the Human Hippocampus and Related Areas: Correspondence between Ex-Vivo MRI and Histological Preparations

The decrease of volume estimates in different structures of the medial temporal lobe related to memory correlate with the decline of cognitive functions in neurodegenerative diseases. This study presents data on the association between MRI quantitative parameters of medial temporal lobe structures and their quantitative estimate in microscopic examination. Twelve control cases had ex-vivo MRI, and thereafter, the temporal lobe of both hemispheres was sectioned from the pole as far as the level of the splenium of the corpus callosum. Nissl stain was used to establish anatomical boundaries between structures in the medial temporal lobe. The study included morphometrical and stereological estimates of the amygdaloid complex, hippocampus, and temporal horn of the lateral ventricle, as well as different regions of grey and white matter in the temporal lobe. Data showed a close association between morphometric MRI images values and those based on the histological determination of boundaries. Only values in perimeter and circularity of the piamater were different. This correspondence is also revealed by the stereological study, although irregular compartments resulted in a lesser agreement. Neither age (< 65 yr and > 65yr) nor hemisphere had any effect. Our results indicate that ex-vivo MRI is highly associated with quantitative information gathered by histological examination, and these data could be used as structural MRI biomarker in neurodegenerative diseases.     

Combined use of digital subtraction angiography and MRI for radiosurgery and stereoencephalography

The authors report their experience with the combined use of digital subtraction angiography (DSA) and magnetic resonance imaging (MRI) for the stereotactic placement of intracerebral electrodes in epilepsy and for the radiosurgical treatment of otherwise inoperable arteriovenous malformations of the brain. Both imaging techniques, when used in conjunction, have been found most useful and complementary. For deep electrode placement, they permit optimal visualization of the cerebral structures to be reached by the electrode array while allowing the avoidance of vessels in the vicinity. For radiosurgery of arteriovenous malformations, DSA provides optimal visualization of the feeders and of the malformation itself, while the MRI reveals the cerebral structures to be spared by the photon beam of the linear accelerator. A discussion of their respective roles is presented, with the specific question as to whether MRI alone could be used for both procedures.     

Acquired coropulmonary and bronchopulmonary anastomoses occurring in association with pulmonary arterial occlusion and veno-occlusive disease generating potential coronary steal

The development of collateral circulation is a general vascular response which is well characterised in the heart. The most common precipitant of this is ischaemia and the most common manifestation is intra coronary collateralisation. Collateral flow between the heart and other thoracic structures is also documented albeit rarely and can be congenital or acquired. In this case report we define a unique case of collateral flow between the coronary and pulmonary circulations in a complex case of mediastinal fibrosis.     

Comparison of 4D Phase-Contrast MRI Flow Measurements to Computational Fluid Dynamics Simulations of Cerebrospinal Fluid Motion in the Cervical Spine

Cerebrospinal fluid (CSF) dynamics in the cervical spinal subarachnoid space (SSS) have been thought to be important to help diagnose and assess craniospinal disorders such as Chiari I malformation (CM). In this study we obtained time-resolved three directional velocity encoded phase-contrast MRI (4D PC MRI) in three healthy volunteers and four CM patients and compared the 4D PC MRI measurements to subject-specific 3D computational fluid dynamics (CFD) simulations. The CFD simulations considered the geometry to be rigid-walled and did not include small anatomical structures such as nerve roots, denticulate ligaments and arachnoid trabeculae. Results were compared at nine axial planes along the cervical SSS in terms of peak CSF velocities in both the cranial and caudal direction and visual interpretation of thru-plane velocity profiles. 4D PC MRI peak CSF velocities were consistently greater than the CFD peak velocities and these differences were more pronounced in CM patients than in healthy subjects. In the upper cervical SSS of CM patients the 4D PC MRI quantified stronger fluid jets than the CFD. Visual interpretation of the 4D PC MRI thru-plane velocity profiles showed greater pulsatile movement of CSF in the anterior SSS in comparison to the posterior and reduction in local CSF velocities near nerve roots. CFD velocity profiles were relatively uniform around the spinal cord for all subjects. This study represents the first comparison of 4D PC MRI measurements to CFD of CSF flow in the cervical SSS. The results highlight the utility of 4D PC MRI for evaluation of complex CSF dynamics and the need for improvement of CFD methodology. Future studies are needed to investigate whether integration of fine anatomical structures and gross motion of the brain and/or spinal cord into the computational model will lead to a better agreement between the two techniques.     

直肠癌MRI研究进展

MRI是目前直肠癌诊断、分期的首选影像学方法。在判断肿瘤对邻近器官、结构的浸润程度上具有明显优势,尤其是对有较高复发风险的低位肿瘤。常规MRI尤其是高分辨MRI能够清晰显示直肠相关解剖,结合扩散加权成像(Diffusion weighted imaging,DWI)通过确定肿瘤边界,直肠系膜有无受侵,淋巴结及远处转移情况,可以准确有效的进行术前诊断、分期;DWI有助于鉴别辅助治疗后失活与存活组织、筛选出辅助治疗有效的患者,在评估治疗后疗效、提示患者预后方面发挥重要作用,也为临床制定治疗方案提供依据。同时也发现准确进行淋巴结分期、鉴别复发仍然存在困难,需要在以后进一步探讨,提高评估的准确性。本文就近年来MRI在直肠癌术前评价、术后疗效评估、复发监测及表观弥散系数(Apparent diffusion coefficient,ADC)的应用做一综述。     

Diagnosis of rheumatoid arthritis of knee joints using magnetic resonance imaging]

A combination of clinical, X-Ray and magnetic resonance tomographic studies for 129 knee joints was made in 85 patients with rheumatoid arthritis of knee joints. MRI symptoms of rheumatoid arthritis of knee joints, including fluid accumulation in the articular cavity, degeneration of the articular cartilage, meniscus, ligaments, proliferation of the synovial membrane, destructive changes in osseous epiphysis were defined. Comparative analysis of the X-Ray and MRI imaging findings has shown that MRI has advantages structures of joints in rheumatoid arthritis.     

直肠癌MRI研究进展

MRI是目前直肠癌诊断、分期的首选影像学方法。在判断肿瘤对邻近器官、结构的浸润程度上具有明显优势,尤其是对有较高复发风险的低位肿瘤。常规MRI尤其是高分辨MRI能够清晰显示直肠相关解剖,结合扩散加权成像（Diffusion weighted imaging,DWI）通过确定肿瘤边界,直肠系膜有无受侵,淋巴结及远处转移情况,可以准确有效的进行术前诊断、分期;DWI有助于鉴别辅助治疗后失活与存活组织、筛选出辅助治疗有效的患者,在评估治疗后疗效、提示患者预后方面发挥重要作用,也为临床制定治疗方案提供依据。同时也发现准确进行淋巴结分期、鉴别复发仍然存在困难,需要在以后进一步探讨,提高评估的准确性。本文就近年来MRI在直肠癌术前评价、术后疗效评估、复发监测及表观弥散系数（Apparent diffusion coefficient,ADC）的应用做一综述。     

Magnetic resonance imaging stereotaxy: recognition and utilization of the commissures

Magnetic Resonance Imaging (MRI) offers a non-invasive method to visualize the intracerebral structures. Coupled to a compatible stereotactic frame and software, MRI can be used to determine the coordinates of intracranial targets. Coordinates of the anterior commissure, posterior commissure, targets and intercommissural distance were obtained from positive contrast ventriculography and by MRI in 6 patients undergoing stereotactic localization prior to the implantation of stimulating thalamic electrodes for pain control. The correlation of coordinates and measurements obtained with ventriculography and MRI is +/- 1 mm in most measurements, but up to 3 mm in 2 cases. Magnetic resonance stereotaxy allows non-invasive and precise localization of intracerebral targets, but does not yet allow its routine use with confidence. Further understanding of distortion and artifacts and corrections of these is mandatory.     

Some aspects of rat femorotibial joint microanatomy as demonstrated by high-resolution magnetic resonance imaging

High-resolution magnetic resonance images (MRI) of the right femorotibial joint of normal Han:Wistar rats were acquired using a 4.7 Tesla magnet and a single-turn solenoid radio frequency coil (built in-house). Some anatomical findings of the rat femorotibial joint, which have not been reported previously using MRI, are described. The separation of patellar ligament and crural fascia was feasible on MRI. This separation would not be seen on images of lower resolution and its presence on high-resolution images could be mistaken for artefact due to the magic angle effect. Band-like fibrous structures exist in the infra-patellar fat pad, which might be mistaken as ligaments within the femorotibial joint. On sagittal MRI a vessel was seen inserted on the central part of the caudal surface of the patellar ligament. Subcutaneous fascia/cutaneous muscles (panniculus carnosus) could also be demonstrated with MRI in the femorotibial joint area.     

Surveying the plant's world by magnetic resonance imaging

Understanding the way in which plants develop, grow and interact with their environment requires tools capable of a high degree of both spatial and temporal resolution. Magnetic resonance imaging (MRI), a technique which is able to visualize internal structures and metabolites, has the great virtue that it is non-invasive and therefore has the potential to monitor physiological processes occurring in vivo. The major aim of this review is to attract plant biologists to MRI by explaining its advantages and wide range of possible applications for solving outstanding issues in plant science. We discuss the challenges and opportunities of MRI in the study of plant physiology and development, plant-environment interactions, biodiversity, gene functions and metabolism. Overall, it is our view that the potential benefit of harnessing MRI for plant research purposes is hard to overrate.     

Gastric magnetic resonance study (methods,semiotics)

The paper shows the potentialities of gastric study by magnetic resonance imaging (MRI). The methodic aspects of gastric study have been worked out. The MRI-semiotics of the unchanged and tumor-affected wall of the stomach and techniques in examining patients with gastric cancer of various sites are described. Using the developed procedure, MRI was performed in 199 patients, including 154 patients with gastric pathology and 45 control individuals who had no altered gastric wall. Great emphasis is placed on the role of MRI in the diagnosis of endophytic (diffuse) gastric cancer that is of priority value in its morphological structure. MRI was found to play a role in the diagnosis of the spread of a tumorous process both along the walls of the stomach and to its adjacent anatomic structures.     

Comparative characteristics of radiation imaging methods in the diagnosis of sacroiliitis

Patients with sacroiliac joint, injuries, ankylosing spondyloarthritis, or spondyloarthropathy of various genesis were examined. Pelvis x-ray, spiral computed tomography (CT), and magnetic resonance imaging (MRI) were performed. MRI was found to have advantages in the detection and evaluation of the pattern of detectable bone changes. It is inexpedient to use traditional x-ray study and CT for the detection of edematous-infiltrative changes in both osseous and fibrous and soft tissue elements of the joint since the sensitivity of these techniques is insufficient to detect. To analyze detectable changes, it is expedient to use a unified MRI protocol that involves the characteristics of osseous, fibrous, and soft tissue structures of the joint.     

Magnetic resonance imaging in the assessment and surgical management of epilepsy and functional neurological disorders

Magnetic resonance imaging (MRI) offers significant advantages over computerized tomography (CT) and teleradiographic techniques when used for the evaluation and management of epilepsy and functional neurological disorders. Depth recording and radiofrequency electrodes can be more accurately positioned within structures such as the amygdala and hippocampus. The extent of corpus callosum section, lobectomy, topectomy, and radiofrequency stereotactic lesions can now be readily confirmed and related with seizure, neurological, and behavioral outcome. Occult, usually low grade, intraparenchymal neoplasms not visualized on CT scans can be located by MRI and biopsied or excised by MRI stereotactic techniques.