Magnetic resonance quarterly最新文献_第6页

Ultrafast imaging using gradient echoes. 使用梯度回波的超快成像。

Magnetic resonance quarterly Pub Date : 1991-01-01

D Chien, R R Edelman

引用次数: 0

Magnetic resonance imaging in the evaluation of infertile women. 磁共振成像在不孕症妇女评价中的应用。

Magnetic resonance quarterly Pub Date : 1990-10-01

S McCarthy

{"title":"Magnetic resonance imaging in the evaluation of infertile women.","authors":"S McCarthy","doi":"","DOIUrl":"","url":null,"abstract":"Infertility can be due to a variety of causes, ranging from genetic or endocrine disturbances to structural abnormalities. Imaging is often used in the evaluation of anatomic abnormalities. The advent of magnetic resonance imaging (MRI) has greatly improved diagnostic accuracy in the workup of several entities causing infertility. Developmental abnormalities of the reproductive tract are particularly well suited to diagnosis by MRI, which clearly demonstrates the zonal anatomy of the corpus, cervix, and vagina. Correct classification of an anomaly can spare the patient unnecessary laparoscopy or surgery. Leiomyomas, another cause of infertility, are optimally evaluated by MRI, since the size, number, location, and extent of degeneration can be identified. These factors are important in deciding how the leiomyomas will be treated. Adenomyosis can cause uterine enlargement and can be misconstrued as fibroids. MRI is the only noninvasive method that can prospectively diagnose adenomyosis. Ovarian masses can also give rise to infertility. MRI is particularly well suited to clarify whether a mass is uterine or ovarian. It is also much more specific than ultrasound in the differential diagnosis of a mass, especially endometriomas, dermoids, and fibromas. Polycystic ovarian disease, usually diagnosed via hormonal measurements, also has a characteristic appearance on MRI.","PeriodicalId":77248,"journal":{"name":"Magnetic resonance quarterly","volume":"6 4","pages":"239-49"},"PeriodicalIF":0.0,"publicationDate":"1990-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13439196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnetic resonance imaging in the evaluation of gynecologic malignancy. 磁共振成像在妇科恶性肿瘤诊断中的应用。

Magnetic resonance quarterly Pub Date : 1990-10-01

K Togashi, J Konishi

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Postoperative and postradiation changes in the pelvis. 骨盆术后和放疗后的变化。

Magnetic resonance quarterly Pub Date : 1990-10-01

H Hricak

引用次数: 0

Fast-scan magnetic resonance: principles and applications. 快速扫描磁共振:原理和应用。

Magnetic resonance quarterly Pub Date : 1990-07-01

F W Wehrli

引用次数: 0

Magnetic resonance contrast media: principles and progress. 磁共振造影剂:原理与进展。

Magnetic resonance quarterly Pub Date : 1990-04-01

R B Lauffer

引用次数: 0

Magnetic resonance contrast agents in the evaluation of the musculoskeletal system. 磁共振造影剂在肌肉骨骼系统评价中的应用。

Magnetic resonance quarterly Pub Date : 1990-04-01

J L Bloem, M F Reiser, D Vanel

引用次数: 0

The role of gadolinium-diethylenetriaminepentaacetic acid in the evaluation of the central nervous system. 钆-二乙烯三胺五乙酸在中枢神经系统评价中的作用。

Magnetic resonance quarterly Pub Date : 1990-04-01

V M Runge, D Y Gelblum

引用次数: 0

Contrast-enhanced magnetic resonance imaging of the abdomen and pelvis. 腹部和骨盆的对比增强磁共振成像。

Magnetic resonance quarterly Pub Date : 1990-04-01

B Hamm, M Laniado, S Saini

{"title":"Contrast-enhanced magnetic resonance imaging of the abdomen and pelvis.","authors":"B Hamm, M Laniado, S Saini","doi":"","DOIUrl":"","url":null,"abstract":"Contrast media in magnetic resonance imaging (MRI) of the abdomen and pelvis are applied for various purposes; different substances and forms of application must be distinguished. Oral contrast agents are primarily used to enhance the discrimination of the intestine from the other organs and from pathological lesions. Clinical studies of i.v. contrast agents focus on two substances: gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) and superparamagnetic iron oxide. Whereas dynamic Gd-DTPA-enhanced MRI improves the differential diagnosis of focal hepatic lesions, iron oxide is a promising agent for increasing the sensitivity of MRI in the detection of hepatic and splenic tumors. Dynamic Gd-DTPA-enhanced MRI of the kidney allows functional assessment of this organ; good demarcation of kidney tumors is only achieved during the early phase of a dynamic examination. In the assessment of adrenal lesions, dynamic Gd-DTPA-enhanced MRI permits better differentiation of adenoma from malignancy. Intravenous Gd-DTPA also appears to be useful in the staging of urinary bladder tumors to distinguish between superficial and infiltrating tumors. Although offering no major diagnostic advantage in the staging of cervical carcinomas, Gd-DTPA-enhanced MRI improves the discrimination of necrotic tumor portions of endometrial carcinoma and allows good differentiation of this lesion from fluid retained in the uterine cavity. Studies of new contrast agents for MRI of the abdomen, which have so far only been investigated in animal experiments, focus on liver imaging. These substance include hepatobiliary agents, Gd-DTPA-containing liposomes, and paramagnetic macromolecules.","PeriodicalId":77248,"journal":{"name":"Magnetic resonance quarterly","volume":"6 2","pages":"108-35"},"PeriodicalIF":0.0,"publicationDate":"1990-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13355715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnetic resonance imaging of bone marrow: diagnostic value in diffuse hematologic disorders. 骨髓磁共振成像:弥漫性血液病的诊断价值。

Magnetic resonance quarterly Pub Date : 1990-01-01

R M Steiner, D G Mitchell, V M Rao, S Murphy, M D Rifkin, D L Burk, S K Ballas, S Vinitski

{"title":"Magnetic resonance imaging of bone marrow: diagnostic value in diffuse hematologic disorders.","authors":"R M Steiner, D G Mitchell, V M Rao, S Murphy, M D Rifkin, D L Burk, S K Ballas, S Vinitski","doi":"","DOIUrl":"","url":null,"abstract":"Magnetic resonance imaging (MRI) has value in characterizing normal and abnormal bone marrow because of its ability to distinguish fat from other tissues. Due to this advantage, hematologic disorders resulting in alterations of the normal cellular and fatty marrow distribution can be appreciated. In this article, the role of MRI in diffuse hematologic disorders is emphasized. At birth, almost all marrow is cellular, but by age 25, cellular marrow is restricted to the axial skeleton and proximal femoral and humeral metaphysis. The remainder is fatty, consisting of 80% fat, 15% water, and 5% protein. With increased need for hematopoiesis, reconversion from fatty to cellular marrow occurs in many diffuse disease states. Diffuse diseases that affect bone marrow production are divided into four categories representing conditions that affect the pluripotent hematopoietic stem cell. These include stem cell failure resulting in aplastic anemia, uncontrolled stem cell proliferation as exemplified by polycythemia vera, stem cell dysplasia such as sickle cell anemia, and malignant transformations or replacement. The MRI appearance of these disorders is discussed in this article. The use of spin-echo (SE) sequences is the most common approach to bone marrow imaging. With T1-weighted SE images, fatty marrow will appear bright and cellular marrow, with lower fat content, will exhibit a lower density signal. With T2-weighted SE pulse sequences, contrast between fatty marrow and cellular marrow decreases. Contrast between fatty and cellular marrow is enhanced with chemical shift imaging, including Dixon out-of-phase imaging, as emphasized in this article. MRI presents a more global view of the bone marrow than biopsy material and should provide a better understanding of diffuse hematologic disease progression and resolution.","PeriodicalId":77248,"journal":{"name":"Magnetic resonance quarterly","volume":"6 1","pages":"17-34"},"PeriodicalIF":0.0,"publicationDate":"1990-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13353486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0