The document discusses various contrast media used in radiology including iodinated contrast media, barium sulfate, gadolinium, and ultrasound contrast agents. It provides classifications of contrast media based on their atomic number, water solubility, and excretion route. It describes the differences between high-osmolar and low-osmolar iodinated contrast media and their safety profiles. MRI contrast agents discussed include gadolinium chelates and their indications. The document also covers ultrasound contrast microbubbles and their encapsulation, as well as barium sulfate mixtures used for gastrointestinal imaging.
1. Contrast agents are substances that have different atomic numbers or electron densities than surrounding tissues, allowing visualization of internal organs on imaging.
2. Early contrast agents included barium sulfate, iodinated compounds, and air or CO2. Modern agents are classified as ionic or non-ionic monomers and dimers with varying osmolalities and viscosities.
3. Contrast agents are used with multiple imaging modalities like CT, MRI, ultrasound, and fluoroscopy. They are administered orally, intravenously, or directly into structures. The choice depends on the physical properties and safety of the specific agent and the anatomy being imaged.
This document provides an overview of contrast media used in radiology. It discusses the history of contrast media beginning with their discovery in 1896. It then covers the basics of contrast media including their physiology, modes of administration, classifications for different imaging modalities, and examples of agents used for X-ray/CT, ultrasound, and MR imaging. Specific contrast agents are described in detail including their properties, uses, and side effects. The document emphasizes the importance of using lower osmolar iodinated contrast media to reduce risks when possible.
- Contrast media are substances used in medical imaging to increase radiographic contrast in areas where it was previously low or absent. They improve the visibility of internal structures on scans.
- There are two main types - positive contrast agents, which increase contrast, and negative contrast agents, which decrease contrast. Common positive agents are iodine-based and barium-based. Common negative agents are air and carbon dioxide.
- Contrast media are administered in different ways depending on the area being examined, such as orally, rectally, intravenously, or intra-arterially. They allow detailed examination of organ systems like the gastrointestinal tract, blood vessels, and soft tissues.
This document discusses contrast agents used in medical imaging. It begins by outlining the aims of discussing contrast agents, including why they are used and desirable features. The main types of contrast agents are then described - positive contrast agents like iodine and barium sulfate which increase attenuation, and negative contrast agents like air which decrease attenuation. Methods of administration and examples of examinations using contrast are provided. Risks associated with contrast agents like reactions and nephrotoxicity are also summarized.
The document discusses contrast media reactions, categorizing them as mild, moderate or severe. It describes types of reactions including anaphylactoid, non-anaphylactoid, chemotoxic, vasovagal and combined reactions. Factors that influence reactions are discussed such as physical properties of contrast media, iodine concentration, total volume, injection speed and patient risk factors. Prevention strategies and safer selection of low-osmolar nonionic contrast is emphasized.
A brief of contrast media used in various modalities of radiodiagnosis including barium, USG, CT, and MRI with their advantages and disadvantages and ADR.
Contrast Media Presentation Uploaded by SONU SHARMA
Student of B.Sc Radiography & Imaging Technology 3rd Year
at Pt.B.D.Sharma University of Health & Science ,
P.G.I.M.S. Rohtak,Haryana,India.
1. Contrast agents are substances that have different atomic numbers or electron densities than surrounding tissues, allowing visualization of internal organs on imaging.
2. Early contrast agents included barium sulfate, iodinated compounds, and air or CO2. Modern agents are classified as ionic or non-ionic monomers and dimers with varying osmolalities and viscosities.
3. Contrast agents are used with multiple imaging modalities like CT, MRI, ultrasound, and fluoroscopy. They are administered orally, intravenously, or directly into structures. The choice depends on the physical properties and safety of the specific agent and the anatomy being imaged.
This document provides an overview of contrast media used in radiology. It discusses the history of contrast media beginning with their discovery in 1896. It then covers the basics of contrast media including their physiology, modes of administration, classifications for different imaging modalities, and examples of agents used for X-ray/CT, ultrasound, and MR imaging. Specific contrast agents are described in detail including their properties, uses, and side effects. The document emphasizes the importance of using lower osmolar iodinated contrast media to reduce risks when possible.
- Contrast media are substances used in medical imaging to increase radiographic contrast in areas where it was previously low or absent. They improve the visibility of internal structures on scans.
- There are two main types - positive contrast agents, which increase contrast, and negative contrast agents, which decrease contrast. Common positive agents are iodine-based and barium-based. Common negative agents are air and carbon dioxide.
- Contrast media are administered in different ways depending on the area being examined, such as orally, rectally, intravenously, or intra-arterially. They allow detailed examination of organ systems like the gastrointestinal tract, blood vessels, and soft tissues.
This document discusses contrast agents used in medical imaging. It begins by outlining the aims of discussing contrast agents, including why they are used and desirable features. The main types of contrast agents are then described - positive contrast agents like iodine and barium sulfate which increase attenuation, and negative contrast agents like air which decrease attenuation. Methods of administration and examples of examinations using contrast are provided. Risks associated with contrast agents like reactions and nephrotoxicity are also summarized.
The document discusses contrast media reactions, categorizing them as mild, moderate or severe. It describes types of reactions including anaphylactoid, non-anaphylactoid, chemotoxic, vasovagal and combined reactions. Factors that influence reactions are discussed such as physical properties of contrast media, iodine concentration, total volume, injection speed and patient risk factors. Prevention strategies and safer selection of low-osmolar nonionic contrast is emphasized.
A brief of contrast media used in various modalities of radiodiagnosis including barium, USG, CT, and MRI with their advantages and disadvantages and ADR.
Contrast Media Presentation Uploaded by SONU SHARMA
Student of B.Sc Radiography & Imaging Technology 3rd Year
at Pt.B.D.Sharma University of Health & Science ,
P.G.I.M.S. Rohtak,Haryana,India.
This document summarizes MRI contrast agents. It discusses how contrast agents can directly or indirectly change tissue properties by altering proton density, T1, or T2 relaxation times. Contrast agents are classified as parenteral relaxivity agents that are positive or negative, or parenteral susceptibility agents that are paramagnetic, superparamagnetic, or ferromagnetic. Gadolinium is the most common paramagnetic contrast agent and shortens T1, increasing brightness on T1-weighted images. Iron oxide particles are negative contrast agents that cause T2 shortening and decreased signal. The document reviews safety considerations for contrast agents and potential adverse reactions.
This document discusses various techniques for reducing radiation dose in computed tomography (CT) scans. It outlines strategies such as using automatic exposure control, adjusting scan parameters based on patient size, employing noise-tolerant images when possible, limiting scan lengths and phases, and utilizing newer reconstruction techniques. The goal is to lower radiation dose without compromising diagnostic image quality.
This document provides an overview of contrast media including its introduction, mechanism of action, basic chemistry and properties, classifications, commonly used preparations, pharmacodynamics, interactions with body systems, potential side effects and their management, and prevention strategies. Contrast media helps improve visualization of tissues during medical imaging by increasing beam attenuation. Iodine is commonly used as the contrast agent due to its high atomic number. Both ionic and non-ionic varieties exist with different properties. Potential side effects range from minor to severe reactions.
Contrast agents are substances used in radiography to improve visualization of internal structures. They can be radiopaque (positive contrast) or non-radiopaque (negative contrast). Iodinated contrast media are commonly classified based on their ionicity, osmolality, and viscosity. Low osmolar contrast media including non-ionic dimers and monomers are preferred due to their favorable safety profile. Ultrasound contrast agents contain microscopic gas-filled bubbles that strongly reflect ultrasound waves, increasing echogenicity and tissue contrast.
This document provides information on contrast media used in radiology, including barium sulfate, gadolinium-based contrast agents, and ultrasound contrast agents. It discusses the properties, uses, advantages, and disadvantages of different non-iodinated and iodinated contrast media. Specific contrast agents are described in detail, along with their mechanisms of action, safety considerations, and future directions for contrast media.
This document provides an overview of radiographic contrast media. It discusses how contrast media enhance images by increasing the absorption of x-rays in certain tissues. It describes the ideal properties of contrast media and classifications such as iodinated versus non-iodinated, ionic versus non-ionic, monomer versus dimer. Examples are given for different types of contrast media including barium sulfate, iodinated monomers and dimers, oil-soluble agents, and MRI contrast agents containing gadolinium. The document covers the history, properties, advantages, disadvantages and examples of various contrast media used in radiology.
Macroradiography is a radiographic technique used to magnify images relative to the object being imaged. It works by increasing the object-to-film distance, which magnifies the image size. Key factors that affect image quality include geometric unsharpness, which increases with magnification, and limitations of the x-ray tube's fine focal spot, which restricts output. Macroradiography is useful for examining small bony structures and pulmonary patterns at higher magnification.
1) The document discusses the historical development of radiographic contrast media from its earliest uses in the late 19th century to the development of tri-iodinated benzene derivatives and modern low-osmolar non-ionic contrast agents.
2) It covers the ideal characteristics, classification, and basic chemistry of iodinated contrast media including differences between ionic and non-ionic monomers and dimers.
3) The risks of contrast media administration are discussed including predictable chemo-toxic reactions affecting tissues and organ systems as well as unpredictable anaphylactoid reactions.
Here are the answers to your questions:
1. We don't perform sinogram or fistulogram if the patient is having severe pyrexia or localized infection as it may worsen the condition.
2. Thin barium is used in case of suspected TEF as the ionic contrast if inhaled in trachea can cause chemotoxicity i.e. chemopneumonitis/intractable chest infections.
3. No, ionic contrast media should not be given for fistulogram or sinogram as it is irritant and may cause inflammation if extravasated. Only low osmolar non-ionic contrast is used.
4. Generally two images are taken- AP/
Computed tomography (CT) of the head is used to assess head injuries, headaches, dizziness, and symptoms of conditions like aneurysms, bleeding, strokes, and brain tumors. It can also help evaluate the face, sinuses, and skull. CT of the head uses X-rays to generate cross-sectional images of the head and brain which provide more detailed information than regular X-rays, particularly for soft tissues and blood vessels. Common protocols for head CT include non-contrast exams for conditions like trauma or stroke, as well as contrast-enhanced exams to evaluate tumors, aneurysms, or other conditions. Precautions are taken to minimize radiation exposure, especially for children.
Susmita Shrestha presented on contrast media in radiology. The document provided a historical overview of contrast media development beginning in the late 19th century. It described the basic properties and types of contrast media used for X-ray, CT, MRI, and ultrasound imaging. Contrast media allow tissues and structures to be more clearly visualized and include barium, iodine, gadolinium, and microbubbles depending on the imaging modality. The optimal contrast medium maximizes visibility while minimizing toxicity.
This document provides information about small bowel imaging techniques. It discusses barium follow through examinations, where barium is ingested and x-rays are taken periodically to image the small bowel. It also describes dedicated small bowel follow through exams using single contrast techniques and positioning to visualize different parts of the bowel. Other small bowel imaging methods discussed include enteroclysis, peroral pneumocolon, and reflux examinations. The document provides details on the indications, contraindications, and interpretation of small bowel imaging studies.
This document provides an overview of diffusion weighted imaging (DWI) and its clinical applications. It defines diffusion and how DWI is acquired using Stejskal-Tanner pulsed gradient spin echo sequences. Key terms like b-value and apparent diffusion coefficient are explained. Clinical uses of DWI include detecting acute strokes and differentiating lesions. Body DWI using DWIBS is also discussed. Diffusion tensor imaging is introduced as a technique for visualizing white matter tract orientation using tractography maps.
This document provides information about contrast agents used in CT scans, including intravenous, oral, and rectal contrast. It discusses the four main types of contrast agents and how they work to enhance organs and tissues on CT images. It also addresses potential adverse effects of intravenous contrast agents and recommendations for reducing risks. Safety considerations are outlined for patients with renal insufficiency, diabetes, cardiovascular disease, and other conditions. Guidelines are provided for dosages of oral and intravenous contrast depending on the area of the body being examined.
Adverse reactions and management of contrast reactions Ashim Budhathoki
The document provides information on contrast media used in medical imaging. It begins with acknowledging those who helped with the project. It then discusses the objectives of the study which are to define contrast media, explain types and reactions, and responsibilities during contrast studies. The document classifies contrast media as positive or negative. Positive contrast media make structures appear brighter on images while negative contrast media make structures appear darker. It provides details on various contrast agents used for different medical imaging modalities like CT, MRI, ultrasound and their routes of administration.
Beam hardening artifact occurs when an X-ray beam passes through multiple materials of varying densities within a scan volume. This causes the beam to become harder as lower energy photons are preferentially absorbed, leading to streaks or shading in the reconstructed CT image. Photon starvation is another cause of streak artifacts, occurring when there is insufficient photon flux passing through areas of higher attenuation, such as across the shoulders. Adaptive filtering and modulating tube current based on attenuation can help reduce these artifacts. Ring artifacts from defective detector elements in older CT scanners appear as rings in the reconstructed images.
This document discusses contrast reactions and their management. It begins by stating that contrast reactions can range from minor to life-threatening. Proper preparation is needed to treat all potential adverse events. Risk factors for reactions include previous reactions, renal insufficiency, and medications. Reactions are classified as idiosyncratic or non-idiosyncratic. Idiosyncratic reactions are unpredictable and severe. Non-idiosyncratic reactions depend on properties of the contrast agent like osmolality. Management involves stabilizing airway, breathing, and circulation. Specific treatments are outlined for mild, moderate, and severe reactions like urticaria, bronchospasm, and hypotension.
The document discusses trauma radiography procedures and best practices. It outlines the different levels of trauma centers and describes specialized equipment used in trauma imaging. Key responsibilities of the radiographer are to perform diagnostic imaging quickly and accurately while prioritizing patient safety and ethical practices. Standard trauma projections are described for various body regions as well as considerations for patient positioning and immobilization.
This document discusses contrast media used in medical imaging. It begins by classifying contrast media as either iodinated or non-iodinated, focusing on barium sulfate as a common non-iodinated contrast agent used for gastrointestinal imaging. The document then discusses gadolinium-based contrast agents used in MRI and microbubble contrast agents used in ultrasound imaging. It covers the properties, mechanisms, safety considerations and future directions for these different contrast media types.
This document summarizes MRI contrast agents. It discusses how contrast agents can directly or indirectly change tissue properties by altering proton density, T1, or T2 relaxation times. Contrast agents are classified as parenteral relaxivity agents that are positive or negative, or parenteral susceptibility agents that are paramagnetic, superparamagnetic, or ferromagnetic. Gadolinium is the most common paramagnetic contrast agent and shortens T1, increasing brightness on T1-weighted images. Iron oxide particles are negative contrast agents that cause T2 shortening and decreased signal. The document reviews safety considerations for contrast agents and potential adverse reactions.
This document discusses various techniques for reducing radiation dose in computed tomography (CT) scans. It outlines strategies such as using automatic exposure control, adjusting scan parameters based on patient size, employing noise-tolerant images when possible, limiting scan lengths and phases, and utilizing newer reconstruction techniques. The goal is to lower radiation dose without compromising diagnostic image quality.
This document provides an overview of contrast media including its introduction, mechanism of action, basic chemistry and properties, classifications, commonly used preparations, pharmacodynamics, interactions with body systems, potential side effects and their management, and prevention strategies. Contrast media helps improve visualization of tissues during medical imaging by increasing beam attenuation. Iodine is commonly used as the contrast agent due to its high atomic number. Both ionic and non-ionic varieties exist with different properties. Potential side effects range from minor to severe reactions.
Contrast agents are substances used in radiography to improve visualization of internal structures. They can be radiopaque (positive contrast) or non-radiopaque (negative contrast). Iodinated contrast media are commonly classified based on their ionicity, osmolality, and viscosity. Low osmolar contrast media including non-ionic dimers and monomers are preferred due to their favorable safety profile. Ultrasound contrast agents contain microscopic gas-filled bubbles that strongly reflect ultrasound waves, increasing echogenicity and tissue contrast.
This document provides information on contrast media used in radiology, including barium sulfate, gadolinium-based contrast agents, and ultrasound contrast agents. It discusses the properties, uses, advantages, and disadvantages of different non-iodinated and iodinated contrast media. Specific contrast agents are described in detail, along with their mechanisms of action, safety considerations, and future directions for contrast media.
This document provides an overview of radiographic contrast media. It discusses how contrast media enhance images by increasing the absorption of x-rays in certain tissues. It describes the ideal properties of contrast media and classifications such as iodinated versus non-iodinated, ionic versus non-ionic, monomer versus dimer. Examples are given for different types of contrast media including barium sulfate, iodinated monomers and dimers, oil-soluble agents, and MRI contrast agents containing gadolinium. The document covers the history, properties, advantages, disadvantages and examples of various contrast media used in radiology.
Macroradiography is a radiographic technique used to magnify images relative to the object being imaged. It works by increasing the object-to-film distance, which magnifies the image size. Key factors that affect image quality include geometric unsharpness, which increases with magnification, and limitations of the x-ray tube's fine focal spot, which restricts output. Macroradiography is useful for examining small bony structures and pulmonary patterns at higher magnification.
1) The document discusses the historical development of radiographic contrast media from its earliest uses in the late 19th century to the development of tri-iodinated benzene derivatives and modern low-osmolar non-ionic contrast agents.
2) It covers the ideal characteristics, classification, and basic chemistry of iodinated contrast media including differences between ionic and non-ionic monomers and dimers.
3) The risks of contrast media administration are discussed including predictable chemo-toxic reactions affecting tissues and organ systems as well as unpredictable anaphylactoid reactions.
Here are the answers to your questions:
1. We don't perform sinogram or fistulogram if the patient is having severe pyrexia or localized infection as it may worsen the condition.
2. Thin barium is used in case of suspected TEF as the ionic contrast if inhaled in trachea can cause chemotoxicity i.e. chemopneumonitis/intractable chest infections.
3. No, ionic contrast media should not be given for fistulogram or sinogram as it is irritant and may cause inflammation if extravasated. Only low osmolar non-ionic contrast is used.
4. Generally two images are taken- AP/
Computed tomography (CT) of the head is used to assess head injuries, headaches, dizziness, and symptoms of conditions like aneurysms, bleeding, strokes, and brain tumors. It can also help evaluate the face, sinuses, and skull. CT of the head uses X-rays to generate cross-sectional images of the head and brain which provide more detailed information than regular X-rays, particularly for soft tissues and blood vessels. Common protocols for head CT include non-contrast exams for conditions like trauma or stroke, as well as contrast-enhanced exams to evaluate tumors, aneurysms, or other conditions. Precautions are taken to minimize radiation exposure, especially for children.
Susmita Shrestha presented on contrast media in radiology. The document provided a historical overview of contrast media development beginning in the late 19th century. It described the basic properties and types of contrast media used for X-ray, CT, MRI, and ultrasound imaging. Contrast media allow tissues and structures to be more clearly visualized and include barium, iodine, gadolinium, and microbubbles depending on the imaging modality. The optimal contrast medium maximizes visibility while minimizing toxicity.
This document provides information about small bowel imaging techniques. It discusses barium follow through examinations, where barium is ingested and x-rays are taken periodically to image the small bowel. It also describes dedicated small bowel follow through exams using single contrast techniques and positioning to visualize different parts of the bowel. Other small bowel imaging methods discussed include enteroclysis, peroral pneumocolon, and reflux examinations. The document provides details on the indications, contraindications, and interpretation of small bowel imaging studies.
This document provides an overview of diffusion weighted imaging (DWI) and its clinical applications. It defines diffusion and how DWI is acquired using Stejskal-Tanner pulsed gradient spin echo sequences. Key terms like b-value and apparent diffusion coefficient are explained. Clinical uses of DWI include detecting acute strokes and differentiating lesions. Body DWI using DWIBS is also discussed. Diffusion tensor imaging is introduced as a technique for visualizing white matter tract orientation using tractography maps.
This document provides information about contrast agents used in CT scans, including intravenous, oral, and rectal contrast. It discusses the four main types of contrast agents and how they work to enhance organs and tissues on CT images. It also addresses potential adverse effects of intravenous contrast agents and recommendations for reducing risks. Safety considerations are outlined for patients with renal insufficiency, diabetes, cardiovascular disease, and other conditions. Guidelines are provided for dosages of oral and intravenous contrast depending on the area of the body being examined.
Adverse reactions and management of contrast reactions Ashim Budhathoki
The document provides information on contrast media used in medical imaging. It begins with acknowledging those who helped with the project. It then discusses the objectives of the study which are to define contrast media, explain types and reactions, and responsibilities during contrast studies. The document classifies contrast media as positive or negative. Positive contrast media make structures appear brighter on images while negative contrast media make structures appear darker. It provides details on various contrast agents used for different medical imaging modalities like CT, MRI, ultrasound and their routes of administration.
Beam hardening artifact occurs when an X-ray beam passes through multiple materials of varying densities within a scan volume. This causes the beam to become harder as lower energy photons are preferentially absorbed, leading to streaks or shading in the reconstructed CT image. Photon starvation is another cause of streak artifacts, occurring when there is insufficient photon flux passing through areas of higher attenuation, such as across the shoulders. Adaptive filtering and modulating tube current based on attenuation can help reduce these artifacts. Ring artifacts from defective detector elements in older CT scanners appear as rings in the reconstructed images.
This document discusses contrast reactions and their management. It begins by stating that contrast reactions can range from minor to life-threatening. Proper preparation is needed to treat all potential adverse events. Risk factors for reactions include previous reactions, renal insufficiency, and medications. Reactions are classified as idiosyncratic or non-idiosyncratic. Idiosyncratic reactions are unpredictable and severe. Non-idiosyncratic reactions depend on properties of the contrast agent like osmolality. Management involves stabilizing airway, breathing, and circulation. Specific treatments are outlined for mild, moderate, and severe reactions like urticaria, bronchospasm, and hypotension.
The document discusses trauma radiography procedures and best practices. It outlines the different levels of trauma centers and describes specialized equipment used in trauma imaging. Key responsibilities of the radiographer are to perform diagnostic imaging quickly and accurately while prioritizing patient safety and ethical practices. Standard trauma projections are described for various body regions as well as considerations for patient positioning and immobilization.
This document discusses contrast media used in medical imaging. It begins by classifying contrast media as either iodinated or non-iodinated, focusing on barium sulfate as a common non-iodinated contrast agent used for gastrointestinal imaging. The document then discusses gadolinium-based contrast agents used in MRI and microbubble contrast agents used in ultrasound imaging. It covers the properties, mechanisms, safety considerations and future directions for these different contrast media types.
This document discusses various contrast agents used in medical imaging. It begins by defining contrast agents and describing their classification. It then focuses on water soluble iodinated contrast agents, describing their physiology and classifications including conventional high osmolar agents, low osmolar agents, and iso-osmolar agents. The document also discusses ultrasound contrast agents, their generations and mechanisms of action. It concludes by covering MR contrast agents such as gadolinium chelates and their uses and properties.
Contrast agents are used to highlight areas of the body during imaging procedures. They work by enhancing the density of tissues so they appear differently than surrounding areas. There are two main types - negative contrast agents which appear darker, and positive contrast agents which appear brighter. Barium sulfate is commonly used orally or rectally for GI studies, while iodine compounds are used for angiography and urography. Ideal contrast agents are water soluble, chemically stable, non-toxic, and selectively excreted by the kidneys. High osmolar ionic dimeric and monomeric agents can cause more adverse effects than low osmolar non-ionic variants. Newer non-ionic dimeric and monom
The document discusses contrast agents used in medical imaging, including desirable properties like safety and effectiveness, types such as positive iodine-based and negative air/gas agents, administration methods, and examples of examinations. Adverse effects are outlined for different contrast media based on properties like osmolality and ionicity. The ideal contrast agent is described as having high solubility, stability, biocompatibility, and selective excretion with minimal adverse impacts.
Contrast media are agents used to improve visualization of internal structures that otherwise cannot be seen clearly. There are two main types - positive contrast agents that are radiopaque, and negative contrast agents that are not. Iodinated contrast media are most commonly used today. They can be ionic monomers, ionic dimers, non-ionic monomers or non-ionic dimers. The ideal contrast medium has high solubility, stability, low toxicity and viscosity, and is excreted selectively like by the kidneys. Ultrasound contrast agents contain microbubbles that enhance echogenicity and improve tissue contrast. They act by resonating within the ultrasound beam. Newer agents use more stable low solubility gases and encapsulation to increase
Contrast media are agents used to improve visualization of internal structures in medical imaging. They work by increasing the contrast between tissues. Contrast media can be classified as positive or negative based on whether they appear bright or dark on images. The main types of contrast media used are barium sulfate for x-rays and iodinated compounds for CT and angiography. Ultrasound contrast agents contain microbubbles that enhance backscatter and improve tissue contrast on ultrasound images. They allow better evaluation of organ perfusion and detection of abnormalities. Contrast media are important tools that improve diagnostic accuracy in medical imaging.
This document discusses the history and use of contrast media and emergency drugs for radiology procedures. It begins by outlining the early discoveries of contrast agents from the 1890s to the 1920s. It then describes how contrast agents are administered and their properties like osmolality and viscosity. The document discusses common contrast agents like barium, iodine-based agents, and categorizes them as high vs low osmolar. It outlines risks of contrast media and expected adverse reaction rates. The document concludes by listing emergency equipment needed to treat potential severe reactions.
The document discusses the history and types of contrast media and emergency drugs used in radiology. It provides details on:
- The development of contrast media from early toxic substances like bismuth and sodium iodide to safer iodine-based agents.
- How contrast media are classified based on osmolality as high osmolar, low osmolar, and iso-osmolar, and whether they are ionic or non-ionic.
- Common reactions to contrast media ranging from mild nausea to life-threatening emergencies, and the emergency equipment and drugs needed to treat reactions.
THIS PRESENTAION CLEARLYEXPLINS ABOUT CONTRAST MEDIA ,T1 AND T2 AGENTS USED IN MRI IAMGING.
IT ALSO SHOWS RELAXIVITY AND ITS FORMULA AND CONTRAST ADMINISTRATION I.E,GADOLINIUM. AND CLASSIFICATION OF MRI CONTRAST AGENTS.
This document discusses different types of contrast agents used in medical imaging. It describes:
1. Positive contrast agents like iodine and barium that appear white on images as they attenuate x-rays more than soft tissue. Negative contrast agents like air and CO2 appear dark as they attenuate x-rays less.
2. Iodinated contrast agents are most commonly used. They are classified as high-osmolar ionic monomers, low-osmolar ionic dimers and non-ionic monomers/dimers based on their molecular structure and osmolarity.
3. Important factors for contrast agents include water solubility, stability, biocompatibility, and renal excretion.
basics of contrastmedia-171027192651.pdfAIDA BORLAZA
This document provides an overview of contrast media used in medical imaging. It discusses the history of contrast media beginning with their discovery in 1896. It then covers the physiology of contrast agents, how they are administered and classified. Specific contrast media are described for X-ray/CT including barium sulfate and iodinated agents. Ultrasound contrast media consisting of gas-filled microbubbles are also outlined. The document provides details on the various generations of contrast agents developed for optimal imaging and safety.
This document provides an overview of contrast media used in medical imaging, including barium sulfate, iodinated contrast media, and gas agents. It discusses the classification, properties, administration, and adverse reactions of different contrast types. Barium sulfate is described as the preferred oral and rectal contrast due to its insolubility, inertness, and ability to coat the gastrointestinal mucosa. Iodinated contrast media are classified based on osmolality, ionicity, and iodine content. Water-soluble iodinated contrasts are preferred over oil-based agents. An ideal contrast is outlined as having properties like water solubility, chemical stability, biological inertness, and renal excretion.
Radioisotopes are unstable isotopes that emit radiation during radioactive decay. They can be naturally occurring or artificially made. There are three main types of radiation emitted - alpha, beta, and gamma rays. Radioisotopes are measured in units like curies and rontgens. They have many medical uses like thyroid scans, bone scans, and PET scans to study metabolism and drug pathways. Radioisotopes are also used in radiotherapy to treat cancer by damaging cells through ionization. However, radiation exposure poses health risks like acute radiation syndrome, increased cancer risks, and genetic effects over generations. Proper safety, storage, disposal and shielding are needed to prevent exposure.
Here are the key steps in administering intravenous contrast media safely:
- Obtain informed consent
- Check for allergies and reactions to previous contrast administrations
- Consider risk factors like renal impairment, diabetes, or cardiac conditions
- Use low-osmolar contrast for high-risk patients
- Monitor vital signs during and after injection
- Have resuscitation equipment and medications available in case of reaction
Infrared spectroscopy is a technique used to identify chemical functional groups in molecules by detecting the vibrational transitions of bonds between atoms. It works by measuring how infrared radiation is absorbed by a sample based on the vibrational frequencies of the chemical bonds present. The main components of an IR spectrometer are an infrared radiation source, a sample holder, a detector, and a recorder. Factors like electronic effects, hydrogen bonding, and bond angles can affect the vibrational frequencies observed in IR spectra. Infrared spectroscopy has many applications including structure elucidation and identification of organic compounds.
This document discusses the process of decalcification for histopathology specimen preparation. Decalcification is required to remove calcium salts from tissues like bone and teeth prior to sectioning, as calcium makes the tissues too hard. The key methods discussed are acid decalcification using agents like hydrochloric acid or formic acid, and chelating agent decalcification using EDTA. Factors that influence the decalcification rate and techniques for determining when decalcification is complete are also outlined.
The document discusses hydrogen peroxide stabilization using chemical stabilizers. It aims to find a stabilizer that restricts the auto-decomposition of hydrogen peroxide without catalytic poisoning. Stabilizers are chemical compounds that delay the auto-catalytic decomposition of hydrogen peroxide, improving storage stability. Sodium stannate and 8-hydroxyquinoline are discussed as effective stabilizers that deactivate catalytic metal ions and increase the shelf life of hydrogen peroxide solutions. The decomposition rate of hydrogen peroxide is analyzed under various conditions like temperature, pH, concentration, and presence of catalytic impurities. Direct titration and gas evolution methods are also described to determine the decomposition rate.
This document provides information on various intravenous contrast agents used in radiology. It discusses iodinated contrast agents used for CT imaging, classified based on their ionicity and molecular structure. Adverse reactions and safety considerations are covered. Contrast agents used for ultrasound imaging are also mentioned. The document concludes with details about MRI contrast agents, which alter proton relaxation to brighten or darken images. Paramagnetic and superparamagnetic agents commonly used are gadolinium and iron oxide particles respectively.
Radiographic Contrast Agents And Contrast-induced Nephropathy
All contrast agents have a basic structure of a benzene ring, which is composed of 6 joined carbon atoms, each of which has an attached hydrogen atom.
Contrast media consist of triiodinated benzene rings, whereby 3 hydrogen atoms are replaced with attached iodine atoms.
Monomers contain 1 triiodinated benzene ring, and dimers contain 2 triiodinated benzene rings
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Skull base tumors & perineural spread radiology ppt This powerpoint presentation includes important anatomy and important pathology of skull base lesion with its imaging feature as well as its ct mri image. This will help alot. this will help for radiology resident as well as ent .
Salivary gland imaging radiology ppt . This powerpoint presentation includes important anatomy and important pathology of salivary gland with its imaging feature as well as its ct mri image. This will help alot. this will help for radiology resident as well as ent .
MRI anatomy of ankle radiology ppt pk is nice presentation that covers cross sectional anatomy as well as relevant anatomy from standard radiology book like CT MRI whole body by Hagga . cross section of mri is taken from mrimaster.com. This will help for radiology resident as well radiographers.
Congenital neck mass radiology pk final is very good power point presentation for radiologist, radiology resident, student and even ent surgeon or resident doctor.. Every disease of neck lesion is properly describe with multi usg, ct and MRI images. this will help a lot. thanks.
Imaging of paranasal sinuses (including anatomy and varaints)pk1 pdf pptDr pradeep Kumar
This is very good powerpoint presentation of imaging anatomy and variants of paranasal sinuses and imaging pathology as well as multiple pathological imaging findings and images.it will helps for radiologist and radiology resident and even ent resident. our references is CT and mri whole body by Haaga and various internet sources. THANKS.
Important radiological classification of fracture and AVNDr pradeep Kumar
This is Important radio-logical classification of fracture and AVN, I made this from various references like radiopaedia and radiology website , It will help for radiology resident, radiologist and even orthopedics resident. Thanks.
This document discusses the principles and techniques of triple phase CT for liver imaging. It begins by explaining hepatic contrast enhancement and the dual blood supply of the liver. It then describes how lesions are detected based on attenuation differences between the lesion and normal liver tissue. The three phases of CT - arterial, portal venous, and delayed equilibrium - are outlined in detail, including optimal timing, contrast injection rates, and what types of lesions enhance in each phase. Specific protocols for the detection and characterization of liver lesions are provided.
This document provides details on MRI imaging of the knee and ankle, including:
- Muscles and ligaments relevant to the knee and ankle
- Imaging modalities used including MRI sequences and technical considerations
- Anatomy and normal appearances of structures like the menisci, ACL, PCL, MCL, LCL
- Descriptions and diagrams of MRI slices in the sagittal, coronal, and axial planes
- Checklist for evaluating ankle MRI focusing on bones, joints, ligaments, and tendons
This presentation include biliary anatomy ,indication, contraindication post op care of percutaneus transhepatic biliary drainage with important technique. and advantage and disadvantage of different technique. This is important for radiologist, radiographers, intervention radiologist radiology resident. Thanks
This power-point presentation is very important for radiology resident radiologist and radiographers and technician. this includes principles, technique , biological effects of radiation and how to protect, whats should normal radiation dose with latest update. This slide also includes ALARA PRINCIPLE thanks.
This document discusses various components of an MRI system including magnets, RF coils, gradient coils, and safety considerations. It describes the different types of magnets used in MRI like permanent, resistive, and superconducting magnets. It explains the purpose and types of RF coils and gradient coils used to generate the magnetic field gradients needed for spatial encoding in MRI. Safety aspects such as screening for metallic objects, specific absorption rate limits, and absolute contraindications for MRI are also summarized.
Barium meal ppt presentation is very important for radiology resident , radiologist and radiographers. this slide contents lots of barium image and technique, position, indication and modification and lots of information. this presentation help alot thanks .
Sellar, Suprasellar and Pineal tumor final pk .pptDr pradeep Kumar
this is very good presentation slide for radiologist and radiology resident. our references is authentic and most are from osborn brain imaging 2nd edition. This deal with sellar, suprasellar and pineal tumor . This help alot. thanks
How to Manage Your Lost Opportunities in Odoo 17 CRMCeline George
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
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How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
2. 2)CONTRAST MEDIUM:
It is a chemical substance of very high or very
low atomic number or weight, therefor it
increase or decrease the density of the organ
under examination. OR
A substance which when introduced into the
body will increase the radiographic contrast in
an area where it was absent or low before.
3. CLASSIFICATION OFCONTRASTMEDIA
Oily/non water soluble
IODINATED CM
Water soluble
IODINATED CM
Renal
excretion
Hepatic
excretion
Iopanoic
acidHigh
osmolar
low
osmolar
Ionic
dimers
Non-ionic
monomers
Ionic monomers
IOTHALAMATE
DIATRIZOATE IOXAGLIC ACID
IOCAMIC ACID
METRIZAMIDE
Non ionic
dimers
IOTROL
IOTROLAN
X-RAY & CT ULTRASOUND MRI
Positive CM Negective CM
water,air,CO2
Non water soluble BaSO4
IODINATED CM
4. • Positive
• Water-soluble (Iodinated contrast media) are of two
types- HOCM and LOCM.
• Water-insoluble: Barium sulphate.
• Negative
• CO2
• N2O
• Air
• O2
5. IODINATED CONTRAST MEDIA
• Water-soluble positive contrast media
• Chemically they are the derivatives of 2,4,6
triiodobenzoic ring.
• Clinically classified into two groups
• HOCM
• LOCM
13. HOCM Vs LOCM
HOCM LOCM
• High osmolality
• I to particle ratio 1.5
• All are ionic monomers
• Higher incidence of
adverse rxns and toxic
effects.
• Low osmolality
• I to particle ratio 2, 3 or 6.
• Ionic dimers, non-ionic
monomers and non-ionic
dimers
• Lower incidence of
adverse rxns and toxic
effects.
14. HOCM VS LOCM
HOCM LOCM
Adverse rxns for ionic ICM
( from a large study
comprising 6000 pts)
1.Mild 2.5%
2.Moderate 1.2%
3.Severe 0.4%
Adverse rxn for non-ionic
ICM ( from a large study
comprising 7170 pts)
1.Mild 0.58%
2.Moderate 0.11%
3.Severe 0%
15. HOCM VS LOCM
HOCM LOCM
• Low cost
• Use- used due to
their low cost.
• Expensive
• Use- if cost was not
the factor LOCM
would have replaced
all other ICM .
LOCM are used in
high risk groups.
16. Sodium and meglumine salts
Sodium salts Meglumine salts
1. More neuro and
cardiotoxic.
2. Cause less histamine
release and hence less
chance of bronchospasm.
3. Immediate and delayed
pain at injection site is
more common.
4. Use- preferred in
asthmatic and allergic pts
1. Less so.
2. More histamine. 4 fold rise
of incidence of
bronchospasm compared
to Na salts.
3. Less common.
4. Use- preferred in CNS and
cardiac cases as well as in
cases with volume
overload.
17. MRI CONTRAST MEDIA
• Contrast agents are used in MRI to enhance the inherent
contrast bet tissues .
• Mechanism of action:
• Large magnetic field density due their unpaired
electrons.
• Interacts with the magnetic moments of the protons
in the tissues and so shorten their T1 relaxation time–
increase in signal intensity.
• Electron magnetic moments also cause local changes
in magnetic field, which promotes rapid dephasing of
proton and so shortens the T2 relaxation time. This
rapid T2 relaxation produces reduced signal intensity.
18. MRI CONTRAST AGENTS
MRI contrast agents possess unpaired electron spins.
The agents may be classified into two groups:
A. Oral contrast agents
• Positive contrast; Manganese chloride, oil emulsions
• Negative contrast; Barium, blue berry and pineapple
juice
B. Parenteral contrast agents
19. MRI CONTRAST AGENTS
On the basis of Susceptibility:
• Ferromagnetic
• Paramagnetic
• Super-paramagnetic.
20. MRI CONTRAST AGENTS
On the basis of relaxivity
• Positive relaxation agents (T1 agents)
Eg: Gd, Mn-DPDP
• Negative relaxation agents (T2 agents)
Eg: Iron oxide particles, high dose Gd
21.
22. FERROMAGNETIC
• Have magnetic moments which align with
scanner’s applied field– maintain their alignment
even after applied field is removed.
• Retained magnetism may cause particle
aggregation and cell function interference.
• So unsafe for MR contrast agents.
• Eg: Iron, Cobalt, Nickel
23. PARAMAGNETIC
• Example: Gadolinium, Oxygen, Melanin
• Have magnetic moments which align to the applied
field
• Alignment return to normal after gradient field is
turned off.
• May be made soluble by chelation and hence can be
used IV.
• Maximum effect is on protons of water molecule,
shortening the T1 relaxation time– increased signal
intensity on T1 images.
24. SUPERPARAMAGNETIC
• Example: Ferrite
• Are aggregation of paramagnetic ions in a
crystalline lattice.
• Cause abrupt change in local magnetic
field which results in rapid proton
dephasing and reduction of T2 relaxation
time: Produce decreased signal intensity
on T2 images.
• Are less soluble than PM agents- So
available only as colloidal suspensions.
25. GADOLINIUM
• Rare earth element
• Atomic number: 64
• Paramagnetic agent
• Usual dose: 0.1mmol/kg
• Median lethal dose: 6-3o mmol/Kg
• Gadolinium chelates: DTPA, DOTA, BOTA
31. INDICATIONS OF GADOLINIUM
• CNS tumours/infections
• Demyelinating disease- acute/ chronic plaques
• More accurate delineation of tumour margins from edema.
• Discrimination of tumour recurrence from post op fibrosis.
• Cardiac and aortic imaging
• Body imaging
36. Contrast Agents in Ultrasound
Requirements:
• Easily introducible in vascular spaces
• Stable for the period of diagnostic examination
• Low toxicity
• Modifying one or more acoustic properties to be detected by
ultrasound beam
37. Contrast Agents in Ultrasound
Requirements:
• Gas microbubbles are used
• Should be less than 7 micron.
• US contrast media depend on interaction between encapsulated microbubbles
and US beam.
• Allow imaging of vascular structures which cannot be evaluated even with
sophisticated doppler techniques.
38. Blood Pool contrast Agents
• Free Gas bubbles
- Agitated normal saline into left ventricle
- Disadvantages;
Large size effectively filtered by lungs
Unstable
• Encapsulated air bubbles
39. US contrast agents
• Levovist
• Most widely used.
• Microbubbles of air enclosed by a thin layer of
palmitic acid in a galactose sol.
• Stable in blood for 1- 4 min.
• Echovist
• Precursor of Levovist
• Bubbles in galactose but no palmitic acid.
• Can’t pass thro pulm beds
• Used for tubal patency.
40. US contrast agents
• Albunex
• Sonicated air microbubbles coated with human serum albumen.
• Used in echocardiography.
• Survives only a short time in left ventricle.
• Little enhancement of arterial tree.
• EchoGen
• An emulsion of dodecafluoropentane which changes its phase converting into
echogenic gas microbubbles by hypobaric activation prior to iv injection.
41. US contrast agents
• SonoVue
• An aqueous suspension of stabilized sulphur hexafluoride microbubbles.
• After reconstitution of the lyophilisate with saline, the suspension is stable
and can be used for upto 4 hrs.
42. GASTROINTESTINAL MRI CONTRAST AGENTS
• Easily miscible with bowel contents
• Palatable
• Two groups:
– Positive agents: Fatty oils and gadolinium. Act by T1 shortening effect.
– Negative agents: Ferrite and barium sulphate; Act by T2 shortening.
44. BARIUM SULPHATE
Barium Mixtures
• Before barium was discovered for use in GI studies,
Bismuth was used with many unwanted effects
because of its solubility.
• Barium, with its high atomic number of 56 and its
insolubility in water is a good contrast agent for GI
examinations because it is very dense and won’t
be absorbed by the GI tract.
• However, suspending agents are required to
counter the insolubility in water.
45. ADDITIVES IN BARIUMS MIXTURES
1. Suspending agents: Keeps barium in solution
2.Vegetable gums Creates viscosity and suspends barium
particles in solution
3.Carboxy Methylcellulose - Avoids clumping of barium and
aids in the dispersion of barium
4.Dispersing agents Keeps barium particles dispersed evenly
throughout the suspension
5.Simethicone - An anti-foam agent prevents air bubble
formation
6.Sorbitol improves the coating qualities of barium. It is
hypertonic and therefore there is a fluid shift into the bowel
lumen, thereby decreasing transit time of barium in the small
bowel.
47. PARTICLE SIZE OF BARIUM
Particles of barium must be small to make them more stable
in suspension. A non-ionic suspension medium is used
otherwise the barium particles would aggregate into
clumps.
Three different sizes of barium particles:
Micronized 1 μ: Used for upper GI,
colon
Colloidal 1/10 μ: Used for small bowel, colon
Variable 1/2-40 μ: Used for upper GI, colon
PH of the Barium suspension is 5.3 which makes it
stable in gastric acid.
48. DENSITY OF BARIUM SUSPENSION
• Density of the Ba suspension can be expressed in terms of
weight/volume or weight/weight.
• Different densities of Ba preparations available for examinations of
different parts of GI tract.
52. • Barium swallow: E-Z HD 250% W/V 100 ml or
more as required.
• Barium meal: E-Z HD 250% W/V 135 ml.
• BFT: E-Z paque 60- 100 % W/V 300 ml
• SBE: E-Z Paque 60% W/V 1500 ml
• Barium enema: Polibar 115% W/V 500 ml or
more as required.
53.
54. ADVANTAGES OF BARIUM
• Excellent coating of mucosa as compared to water-soluble
contrasts.
• Cost
55. DISADVANTAGES OF BARIUM
• High morbidity when Ba is spilled in peritoneal cavity.
• Subsequent CT and US rendered difficult.
57. WATER-SOLUBLE CONTRAST MEDIA
IN GI TRACT
• They are iodinated contrast media and gases.
• Two commonly used ICM agents are
• Iopamidol (gastromiro)- 61% w/v; 300mg iodine per ml sol. This is LOCM.
• Meglumine diatrizoate 66% and sod diatrizoate 10% ( Gastrografin)- 370 mg I per ml sol.
This is HOCM.
58. INDICATIONS OF WATER-SOLUBLE CM IN GI
TRACT:
• Suspected perforation
• Meconium ileus
• To distinguish bowel from other structures on CT.
• LOCM is used if aspiration is a possibility.
59. Complications
• Pulmonary edema if aspirated ( not for LOCM)
• Hypovolemia in children
• Allergic rxn due to absorbed contrast media
• May precipitate in hyperchlorhydric gastric acid( not for non-
ionics)
• Ileus
60. GASEOUS AGENTS IN GI STUDY
• CO2 and air are used in conjunction with Ba for double contrast
effect.
• Air is used in Ba enema.
• CO2 is used in the form of gas producing granules/ powder to
study the upper GI tract in double contrast study.
61. BILIARY CONTRAST MEDIA
• Like conventional urographic contrast media, biliary
contrast media are also triiodobenzoic acid
dearivative.
• Iopanoic acid ( telepaque) was introduced in 1951
and later compounds were all modifications of it.
Differences occur in prosthetic group and amino
group.
• These agents are excreted via biliary route and not
thro kidneys due to the absence of prosthetic group
in position 5.
62. BILIARY CONTRAST MEDIA
• Oral agents-
• Single benzene ring
• Examples are iopnoic acid( telepaque) and sodium ipodate( biloptin). They
come in capsule forms.
• IV agents
• Meglumine iotroxate( biliscopin) is a dimer with the polymethylene chain
connecting the two rings.
• IV agents are rarely used these days.
63. METABOLIC PATHWAY OF ORAL AGENTS
• Absorption from gut by passive diffusion.
• After absorption albumen bound.
• Carried to liver by portal vein.
• In liver taken up by hepatocytes.
• Conjugation with gluduronic acid to form more water soluble glucuronides.
• Excretion into bile is an active process which can become saturated and is the
rate-limiting step.
• Concentrated in gb by absorption of water. Peak opacification of gb occur
after 12 h of ingestion.
• Oral agents are finally excreted in stool. Reabsorption is limited by the fact
that after conjugation they are no longer lipophilic.
105. •
•
•
•
•
•
•
•
•
•
•
• A rising serum creatinine level is
usually the first sign of an impending
change in renal function.
• Serum creatinine level often rises
within the first 24 hours. (Elevation
may not occur for 72 hours).
• Peaks in three to five days.
• Returns to baseline by seven to 10
days after the procedure