Recent advances in bone marrow scanning

Interest in bone marrow scanning has been renewed as the result of the development of radiopharmaceuticals for evaluating specific aspects of bone marrow anatomy, physiology and pathology. This article provides a brief review of bone marrow structure, blood flow and function essential to the understanding of basic principles of bone marrow radionuclide imaging. The prospects and limitations of imaging haematopoietic bone marrow in man using indium 111 chloride, technetium-99m (^99mTc)-labelled microcolloid or^99mTc-labelled monoclonal antigranulocytic and antimyelocytic antibodies are discussed in more detail. The technical aspects of bone marrow scintigraphy are presented. Results of more recent studies evaluating bone marrow scanning in circulatory, inflammatory and in systemic haematological disorders are summarized. Special attention is paid to the concept of bone marrow micrometastases and its implications for the follow-up of patients with malignant tumours. Recent results suggest that immunoscintigraphy of bone marrow may provide a novel and sensitive approach for establishing the presence and extent of bone marrow infiltration.     

骨肿瘤射频消融治疗研究进展

射频消融(RFA)是一项局部、微创治疗,近年来被越来越多的应用到骨肿瘤治疗中,RFA对于缓解失去手术机会的骨转移性病灶引起的疼痛是安全有效的.并可通过联合骨水泥成形术加固消融部位,防止病理性骨折的发生.为临床无法采用其他方法治疗的骨肿瘤患者提供了一项有效的治疗选择.     

骨肿瘤的消融治疗

影像导向下消融技术已广泛应用于全身各种实体肿瘤的治疗.近年该技术逐渐应用到骨肿瘤的治疗.消融治疗能有效缓解肿瘤引起的疼痛,为临床失去外科手术的骨肿瘤患者提供了一项有效的治疗选择.本文从射频消融,微波消融,高强度能量聚焦消融以及冷冻消融治疗骨肿瘤的原理、应用范围、治疗效果进行综述.     

Symmetric visualization of the femoral heads in reticuloendothelial bone marrow scanning in adults

Two hundred and twenty seven consecutive patients of either sex aged 15–84 suffering from various benign and malignant disorders were studied by ^99mTc-HSA-MM reticuloendothelial bone marrow scintigraphy. In all patients, symmetric findings concerning visualization or nonvisualization of the femoral heads could be seen. Femoral heads were clearly visualized in 48%, nonvisualized in 43%, and equivocally visualized in 9%. In patients with clearly visualized femoral heads, the bone marrow showed peripheral extension in 81%, whereas in patients with nonvisualized femoral heads, bone marrow extension was observed in only 42%. There was a correlation between the degree of bone marrow extension and the ability to visualize femoral heads. There was no obvious difference between males and females, nor amongst patients with various diseases or treatments, nor between different age groups. Two hypotheses are suggested to explain the correspondence between presence of bone marrow tissue in the femoral heads and peripheral extension of the bone marrow organ. Nonvisualization of the femoral heads alone is insufficient to establish the diagnosis of avascular necrosis.     

Comparative study of 111In and 59Fe bone marrow scanning

The aim of this work is to examine the relative merits of ⁵⁹Fe and ¹¹¹In scanning in estimating the functional value of the various erythropoietic areas and in appraising bone marrow distribution and extension. At first we studied a group of patients with heterogeneous distribution of bone marrow secondary to irradiation, ferrokinetics serving as reference for the comparison of ¹¹¹In and ⁵⁹Fe scanning. The functional value of ⁵⁹Fe scanning was thus proved, in contrast to ¹¹¹In scanning which was erroneous for 13 of the 29 bone marrow areas studied. A further study of patients presenting polycythemia vera or anemia with ¹¹¹In demonstrated in some cases false distribution and bone marrow extension. Furthermore, ⁵⁹Fe scanning permitted evaluation of the efficiency of erythropoiesis and the existence of extramedullary erythropoiesis. Review of the literature revealed that with the activity used there was no dosimetric advantage of ¹¹¹In over ⁵⁹Fe.Attachée de Recherches INSERM     

Physical requirements of a 59Fe bone marrow distribution digital scanning study

A method is described to provide whole-body scanning of ⁵⁹Fe bone marrow distribution using a tungsten-alloy collimator. The physical requirements of this method were determined by means of dedicated phantoms. As we were only interested in bounded ⁵⁹Fe regions (sacral bone, liver and spleen), it was necessary to subtract the ⁵⁹Fe activity in the blood. An estimate of this activity was obtained by means of ^99mTc-labelled erythrocyte wholebody scanning to which a correction factor K was applied. The independence versus depth was performed by computing geometrical means of prone and supine images. The results of these experiments indicate the possible feasibility of a scanning method for a ferrokinetic study in place of the usual external counting.     

Recent advances in contrast agents

Intravascular contrast agents are remarkably safe and inexpensive. With the recent approval of three new low-osmolality, high-cost contrast media, questions arise as to toxicity, side effects, and choice of particular agents for particular patients and examinations. This article examines the nature and the etiology of the effects of all currently available contrast agents in order to achieve an improved understanding of the relative advantages, disadvantages, and utility of each.     

伤口换药的研究进展

伤口愈合是一个复杂的过程,理念分为干性愈合和湿性愈合。其理念正由传统的干性愈合向现代化的湿性愈合发展,从而奠定了保湿敷料的产生和发展。伤口的评估分类,为换药提供了依据,强调清洗、清创、湿敷在伤口愈合的作用。     

Recent advances in medical physics

Some of the major interests in medical physics over the last few years have concerned the technical advances in Computed Tomography and high field Magnetic Resonance Imaging. This review discusses the introduction of Dual Source CT and explains how it can not only offer faster data acquisition but also operate with lower radiation doses. This provides enormous benefits for all patients, but for cardiac and pediatric examinations in particular. The advances in MRI at 7?T esla are also impressive, with better signal to noise; cardiac and musculoskeletal applications are discussed; technical improvements are work-in-progress for other applications.     

Recent advances in copper radiopharmaceuticals

Copper has five radioisotopes ((60)Cu, (61)Cu, (62)Cu, (64)Cu, and (67)Cu) that can be used in copper radiopharmaceuticals. These radioisotopes decay by mixed emissions of β+, β-, and γ with a wide range of half-lives from 9.74 min ((62)Cu) to 2.58 d ((67)Cu), which enable the design and synthesis of a variety of radiopharmaceuticals for different biomedical applications in diagnostic and therapeutic nuclear medicine. However, due to the availability and production cost, the research efforts in copper radiopharmaceuticals are mainly focused on the use of (64)Cu (t(1/2) = 12.7 h; 17.4% β+, 43% EC, 39% β-), a radioisotope with low positron energy (E β+max = 0.656 MeV) that is ideal for positron emission tomography (PET) imaging quantification and β- emissions along with Auger electron for radiotherapy. Driven by the ever-increasing availability of preclinical and clinical PET scanners, a considerable interest has been seen in the development of novel copper radiopharmaceuticals in the past decade for a variety of diseases as represented by PET imaging of cancer. To avoid unnecessary literature redundancy, this review focuses on the unrepresented research aspects of copper chemistry (e.g. electrochemistry) and their uses in the evaluation of novel nuclear imaging probe design and recent advances in the field towards the practical use of copper radiopharmaceuticals.     

辐射防护药物研究最新进展

电离辐射损伤不仅是一个公众健康问题,同时也是一个国家安全问题。如何获得治疗效果优良、安全性高和不良反应小的辐射防护药物一直是科学家努力研究的目标。近年来,伴随着分子生物学、免疫学等学科的发展,辐射防护药物的研究也取得了较大的突破。目前,诸如5-雄烯二醇（5-AED）、CBLB502、Ex-RAD和HemaMax等药物已获得美国食品药品监督管理局的批准进入临床试验;而新发现的具有潜在价值的LY294002和17-DMAG等药物也正处于研发之中。笔者基于近年来辐射防护领域国外相关刊物和专利的最新发现和进展进行综述。重点放在近几年来出现的药物新进展以及这一时间内治疗急性放射综合征的抗辐射新药上。     

Recent advances in screen-film mammography

Today there are many dedicated mammographic x-ray units available that are capable of providing high-quality screen-film mammograms. Likewise, screen-film combinations designed for mammography are capable of providing images with appropriate contrast, resolution, and noise levels. Proper film processing is most important in order to obtain the appropriate film speed and contrast. A higher-speed screen-film combination designed for mammography can provide mammograms with significantly lower radiation dose, especially for grid and magnification techniques. Designing x-ray units and techniques as well as screen-film combinations with the singular goal of reducing radiation dose will always involve compromises and trade-offs. The key is to always consider optimizing all of the factors that affect image quality: (1) appropriate beam quality, (2) breast compression, (3) consideration of the use of grids, (4) good geometry, (5) selection of an appropriate screen-film combination, and (6) proper film processing. Optimization of all appropriate imaging factors will produce high-quality mammograms at the lowest radiation dose to the patient.     

Recent advances in radionuclide therapy

A variety of radionuclides continue to be investigated and/or clinically used for different therapeutic applications in nuclear medicine. The choice of a particular radionuclide with regard to appropriate emissions, linear energy transfer, and physical half-life is dictated to a large extent by the character of the disease (eg, solid tumor or metastatic disease) and by the carrier used to selectively transport the radionuclide to the desired site. An impressive body of information has appeared in the recent literature that addresses many of these considerations. This article summarizes and discusses the many recent advances and the progress in the clinical applications of therapeutic radionuclides in relatively new and developing areas, such as radioimmunotherapy, peptide therapy, intravascular therapy to prevent restenosis, radiation synovectomy, and bone malignancy therapy. Projections are made as to the future directions and progress in these areas. The crucial issue of a reliable, year-round supply of new and emerging therapeutic radionuclides in quantities sufficient initially for research, and then for routine clinical use, is a very worthy goal which, in the United States, remains to be achieved.     

Recent advances in chest radiography

There have been many remarkable advances in conventional thoracic imaging over the past decade. Perhaps the most remarkable is the rapid conversion from film-based to digital radiographic systems. Computed radiography is now the preferred imaging modality for bedside chest imaging. Direct radiography is rapidly replacing film-based chest units for in-department posteroanterior and lateral examinations. An exciting aspect of the conversion to digital radiography is the ability to enhance the diagnostic capabilities and influence of chest radiography. Opportunities for direct computer-aided detection of various lesions may enhance the radiologist's accuracy and improve efficiency. Newer techniques such as dual-energy and temporal subtraction radiography show promise for improved detection of subtle and often obscured or overlooked lung lesions. Digital tomosynthesis is a particularly promising technique that allows reconstruction of multisection images from a short acquisition at very low patient dose. Preliminary data suggest that, compared with conventional radiography, tomosynthesis may also improve detection of subtle lung lesions. The ultimate influence of these new technologies will, of course, depend on the outcome of rigorous scientific validation.     

The accuracy of 111InCl3 as a bone marrow scanning agent.

The number of normal cellular elements present in bone marrow biopsies was compared to the extent of uptake at corresponding sites on 111InCl3 bone marrow scans in 87 patients with malignant lymphoma. Of the biopsies free of tumor, 49/54 interpreted as normocellular and 16/17 hypocellular or aplastic confirmed the scan interpretation. Of the biopsies demonstrating tumor, 10/11 of those interpreted as normocellular and 14/15 hypocellular or aplastic confirmed the scan interpretation. The 111InCl3 bone marrow scan is accurate in depicting the presence or absence of normal marrow elements, but is of value in detecting tumor only when the normal elements are extensively replaced.