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Iofendylate
Iofendylate is a molecule that was used as a radiocontrast agent, typically for performing myelography studies. It was marketed under the trade names Pantopaque (in North America) and Myodil (rest of the world). Iofendylate is a highly lipophilic (oily) substance and as such it was recommended that the physician remove it from the patient at the end of the myelography study, which was a difficult and painful part of the procedure. Moreover, because complete removal could not always be achieved (or even attempted by some physicians), iofendylate's persistence in the body might sometimes lead to arachnoiditis, a potentially painful and debilitating lifelong disorder of the spine. As a result, the substance, which was used extensively for over three decades, became the subject of multiple lawsuits filed around the world. Iofendylate's use ceased when water-soluble agents suitable for spinal imaging (such as metrizamide) became available in the late 1970s. With those substances it was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metrizamide
Metrizamide is a non-ionic iodine-based radiocontrast agent. It is also a density gradient medium for the centrifugation of biological particles. Historically metrizamide replaced iofendylate (trade names: Pantopaque, Myodil) as the contrast agent of choice for myelography (an X-ray study of the spine now largely replaced by MRI). The radio opacity characteristics are such that finer detail is displayed with metrizamide, as well as the advantage of reabsorption from spinal fluid and excretion from the body – since unlike iofendylate, metrizamide is a water-soluble substance. Both agents are administered by lumbar puncture (also referred to as a spinal tap or cisternal puncture), at the cervicocranial junction. The human patient is rolled from the lateral decubitus (lying on the side) to prone. Ankles are strapped to the end of a hard X-ray, CT, or MRI table. To obtain images of the cervical region the patient is then carefully tilted in the Trendelenberg position (head d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiocontrast Agent
Radiocontrast agents are substances used to enhance the visibility of internal structures in X-ray-based imaging techniques such as computed tomography (contrast CT), projectional radiography, and fluoroscopy. Radiocontrast agents are typically iodine, or more rarely barium sulfate. The contrast agents absorb external X-rays, resulting in decreased exposure on the X-ray detector. This is different from radiopharmaceuticals used in nuclear medicine which emit radiation. Magnetic resonance imaging (MRI) functions through different principles and thus MRI contrast agents have a different mode of action. These compounds work by altering the magnetic properties of nearby hydrogen nuclei. Types and uses Radiocontrast agents used in X-ray examinations can be grouped in positive (iodinated agents, barium sulfate), and negative agents (air, carbon dioxide, methylcellulose). Iodine (circulatory system) Iodinated contrast contains iodine. It is the main type of radiocontrast used for intr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myelography
Myelography is a type of radiographic examination that uses a contrast medium to detect pathology of the spinal cord, including the location of a spinal cord injury, cysts, and tumors. Historically the procedure involved the injection of a radiocontrast agent into the cervical or lumbar spine, followed by several X-ray projections. Today, myelography has largely been replaced by the use of MRI scans, although the technique is still sometimes used under certain circumstances – though now usually in conjunction with CT rather than X-ray projections. Types Cervical myelography This procedure is used to look for the level of where spinal cord disease occurs or compression of the spinal cord at the neck region for those who are unable or unwilling to undergone MRI scan of the spine. Lumbar myelography This procedure is to look for the level of spinal cord disease such as lumbar nerve root compression, cauda equina syndrome, conus medullaris lesions, and spinal stenosis. This is do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiocontrast Agents
Radiocontrast agents are substances used to enhance the visibility of internal structures in X-ray-based imaging techniques such as computed tomography (contrast CT), projectional radiography, and fluoroscopy. Radiocontrast agents are typically iodine, or more rarely barium sulfate. The contrast agents absorb external X-rays, resulting in decreased exposure on the X-ray detector. This is different from radiopharmaceuticals used in nuclear medicine which emit radiation. Magnetic resonance imaging (MRI) functions through different principles and thus MRI contrast agents have a different mode of action. These compounds work by altering the magnetic properties of nearby hydrogen nuclei. Types and uses Radiocontrast agents used in X-ray examinations can be grouped in positive (iodinated agents, barium sulfate), and negative agents (air, carbon dioxide, methylcellulose). Iodine (circulatory system) Iodinated contrast contains iodine. It is the main type of radiocontrast used for i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipophilic
Lipophilicity (from Greek λίπος "fat" and φίλος "friendly"), refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. Such non-polar solvents are themselves lipophilic (translated as "fat-loving" or "fat-liking"), and the axiom that "like dissolves like" generally holds true. Thus lipophilic substances tend to dissolve in other lipophilic substances, but hydrophilic ("water-loving") substances tend to dissolve in water and other hydrophilic substances. Lipophilicity, hydrophobicity, and non-polarity may describe the same tendency towards participation in the London dispersion force, as the terms are often used interchangeably. However, the terms "lipophilic" and "hydrophobic" are not synonymous, as can be seen with silicones and fluorocarbons, which are hydrophobic but not lipophilic. __TOC__ Surfactants Hydrocarbon-based surfactants are compounds that are amphiphilic (or amphipathic), having a h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachnoiditis
Arachnoiditis is an inflammatory condition of the arachnoid mater or 'arachnoid', one of the membranes known as meninges that surround and protect the nerves of the central nervous system, including the brain and spinal cord. The arachnoid can become inflamed because of adverse reactions to chemicals, infection from bacteria or viruses, as the result of direct injury to the spine, chronic compression of spinal nerves, complications from spinal surgery or other invasive spinal procedures, or the accidental intrathecal injection of steroids intended for the epidural space. Inflammation can sometimes lead to the formation of scar tissue and adhesion that can make the spinal nerves "stick" together,NINDS Arachnoiditis Information Page |
The Daily Telegraph (Sydney)
''The Daily Telegraph'', also nicknamed ''The Tele'', is an Australian tabloid newspaper published by Nationwide News Pty Limited, a subsidiary of News Corp Australia, itself a subsidiary of News Corp. It is published Monday through Saturday and is available throughout Sydney, across most of regional and remote New South Wales, the Australian Capital Territory and South East Queensland. A 2013 poll conducted by Essential Research found that the ''Telegraph'' was Australia's least-trusted major newspaper, with 49% of respondents citing "a lot of" or "some" trust in the paper. Amongst those ranked by Nielsen, the ''Telegraph'' website is the sixth most popular Australian news website with a unique monthly audience of 2,841,381 readers. History ''The Daily Telegraph'' was founded in 1879, by John Mooyart Lynch, a former printer, editor and journalist who had once worked on the ''Melbourne Daily Telegraph''. Lynch had failed in an attempt to become a politician and was lookin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elsevier
Elsevier () is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell'', the ScienceDirect collection of electronic journals, '' Trends'', the '' Current Opinion'' series, the online citation database Scopus, the SciVal tool for measuring research performance, the ClinicalKey search engine for clinicians, and the ClinicalPath evidence-based cancer care service. Elsevier's products and services also include digital tools for data management, instruction, research analytics and assessment. Elsevier is part of the RELX Group (known until 2015 as Reed Elsevier), a publicly traded company. According to RELX reports, in 2021 Elsevier published more than 600,000 articles annually in over 2,700 journals; as of 2018 its archives contained over 17 million documents and 40,000 e-books, with over one billion annual downloads. Researchers have criticized Elsevier for its high profit marg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Resonance Imaging
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the organs in the body. MRI does not involve X-rays or the use of ionizing radiation, which distinguishes it from CT and PET scans. MRI is a medical application of nuclear magnetic resonance (NMR) which can also be used for imaging in other NMR applications, such as NMR spectroscopy. MRI is widely used in hospitals and clinics for medical diagnosis, staging and follow-up of disease. Compared to CT, MRI provides better contrast in images of soft-tissues, e.g. in the brain or abdomen. However, it may be perceived as less comfortable by patients, due to the usually longer and louder measurements with the subject in a long, confining tube, though "Open" MRI designs mostly relieve this. Additionally, implants and oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
