Magnetic Resonance - Technology Information Portal Welcome to MRI Technology
Info
  Sheets

Out-
      side
 



 
 'Negative Oral Contrast Agents' 
SEARCH FOR    
 
  2 3 5 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Result : Searchterm 'Negative Oral Contrast Agents' found in 1 term [] and 6 definitions [], (+ 5 Boolean[] results
1 - 5 (of 12)     next
Result Pages : [1]  [2]  [3]
Searchterm 'Negative Oral Contrast Agents' was also found in the following service: 
spacer
Forum  (1)  
 
Negative Oral Contrast AgentsForum -
related threadsInfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.MRI Resource Directory:
 - Contrast Agents -
 
Categories of negative oral contrast agents:
Negative oral contrast media are usually based on superparamagnetic particles and act by inducing local field inhomogeneities, which results in shortening of both T1 and T2 relaxation times. Superparamagnetic contrast agents have predominant T2 weighted effects. Biphasic contrast media are agents that have different signal intensities on different sequences, depending on the concentration at which they are used.
Suitable materials for oral contrast agents should have little or no absorption by the stomach or intestines, complete excretion, no motion or susceptibility artifacts, affordability, and uniform marking of the gastrointestinal tract. Benefits of negative oral contrast agents are the reduction of ghosting artifacts caused by the lack of signal. Superparamagnetic iron oxides produce also in low concentrations a noticeable signal loss; but can generate susceptibility artifacts especially in gradient echo sequences. Perfluorochemicals do not dilute in the bowel because they are not miscible with water.
High cost, poor availability, and limited evaluations of side effects are possible disadvantages.
Negative oral contrast agents are used e.g., in MRCP, where the ingestion of 600-900 ml of SPIO cancels out the signal intensity of the lumen (in addition after the injection of a gadolinium-based contrast medium, the enhancement of the inflammatory tissues is clearer seen), and in MR abdominal imaging of Crohn's disease in combination with mannitol.
mri safety guidance
Contrast Guidance
Blueberry or pineapple juices are useable for examinations of the pancreas (MRCP, upper abdominal imaging) as cheep contrast agents, because of the content of magnetic substances (e.g. manganese).

See also Ferristene, Ferumoxsil, Oral Magnetic Particles, Gastrointestinal Imaging.
spacer
 
• Share the entry 'Negative Oral Contrast Agents':  Facebook  Twitter  LinkedIn  
 
Further Reading:
  Basics:
Components of Oral Contrast Agent for Magnetic Resonance Imaging(.pdf)
   by www.ffcr.or.jp    
MRI Resources 
DICOM - Calculation - Sequences - Jobs - Collections - Cardiovascular Imaging
 
GastroMARK®InfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.MRI Resource Directory:
 - Contrast Agents -
 
GastroMARK® belongs to the negative oral contrast agents (same as Lumirem®, another brand name for ferumoxsil). GastroMARK® is used to distinguish the loops of the bowel from other abdominal structures and physiology. When GastroMARK® is ingested, it flows through and darkens the stomach and the small intestine in 30 to 45 minutes. By more clearly identifying the intestinal loops, GastroMARK® improves visualization of adjacent abdominal tissues such as the pancreas.
Drug Information and Specification
NAME OF COMPOUND
Ferumoxsil, silicone-coated superparamagnetic iron oxide, USAN, AMI-121
CENTRAL MOIETY
Fe3+/Fe2+
CONTRAST EFFECT
T2*enhanced
r1=3.4, r2=3.8, B0=1.0T
PHARMACOKINETIC
Gastrointestinal
OSMOLALITY
250 mosm/kgH2O
CONCENTRATION
52.5mg Fe/300mL
DOSAGE
300 mL oral
PREPARATION
Finished product
INDICATION
Bowel marking
DEVELOPMENT STAGE
For sale
DISTRIBUTOR
See below
PRESENTATION
Bottles containing 300 mL
DO NOT RELY ON THE INFORMATION PROVIDED HERE, THEY ARE
NOT A SUBSTITUTE FOR THE ACCOMPANYING PACKAGE INSERT!
Distribution Information
TERRITORY
TRADE NAME
DEVELOPMENT
STAGE
DISTRIBUTOR
USA
GastroMARK®
For sale
EU
For sale
spacer

• View the DATABASE results for 'GastroMARK®' (6).Open this link in a new window

 
Further Reading:
  Basics:
ferumoxsil, oral suspension GastroMARK GastroMARK ®
MATERIAL SAFETY DATA SHEET
   by dailymed.nlm.nih.gov    
MRI Resources 
Pediatric and Fetal MRI - Spectroscopy - MRCP - MR Myelography - Libraries - Intraoperative MRI
 
Gastrointestinal Paramagnetic Contrast AgentsInfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.MRI Resource Directory:
 - Contrast Agents -
 
Paramagnetic substances, for example Gd-DTPA solutions, are used as MRI oral contrast agents in gastrointestinal imaging to depict the lumen of the digestive organs. Different Gd-DTPA solutions or zeolites containing gadolinium can be used e.g., for diagnosis of delayed gastric emptying, diagnosis of Crohn's disease etc.
Low concentrations of gastrointestinal paramagnetic contrast agents cause a reduction in T1 relaxation time; consequently, these agents act on T1 weighted images by increasing the signal intensity of the bowel lumen. High concentrations cause T2 shortening by decreasing the signal, similar to superparamagnetic iron oxide. Gd-DTPA chelates are unstable at the low pH in the stomach, therefore buffering is necessary for oral use.

See also Gadopentetate Gastrointestinal, Gadolinium Zeolite, Negative Oral Contrast Agents, Gastrointestinal Superparamagnetic Contrast Agents, and Ferric ammonium citrate.
 
Images, Movies, Sliders:
 MR Colonography Gadolinium per Rectum  Open this link in a new window
      

Courtesy of  Robert R. Edelman
 
spacer

• View the DATABASE results for 'Gastrointestinal Paramagnetic Contrast Agents' (5).Open this link in a new window

Searchterm 'Negative Oral Contrast Agents' was also found in the following service: 
spacer
Forum  (1)  
 
Gastrointestinal Superparamagnetic Contrast AgentsInfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.MRI Resource Directory:
 - Contrast Agents -
 
Gastrointestinal (GI) superparamagnetic contrast agents are used in MRI to improve the visualization of e.g., the intestinal tract, the pancreas (see MRCP), etc. Disadvantages are susceptibility artifacts e.g., dependent on delayed imaging or large volumes resulting in artifacts in the colon and distal small bowel loops related to higher concentration of the particles and absorption of the fluid.
Different types of MRI gastrointestinal superparamagnetic contrast agents:
Magnetite albumin microsphere

Usually gastrointestinal superparamagnetic contrast media consist of small iron oxide crystals (ferrites), which produce a signal reduction in the stomach and bowel after oral administration. The T2 shortening caused by these particles is produced from the local magnetic field inhomogeneities associated with the large magnetic moments of superparamagnetic particles. Ferrites are iron oxides of the general formula Fe203.MO, where M is a divalent metal ion and may be mixed with Fe3O4 in different preparations. Ferrites can produce symptoms of nausea after oral administration, as well as flatulence and a transient rise in serum iron. Embedding in inert substances reduce side effects by decreasing the absorption and interaction with body tissues. Combining these contrast materials with polymers such as polyethylene glycol or cellulose, or with sugars such as dextrose, results in improved T1 and/or T2 relaxivity compared with that of the contrast agent alone.

See also Negative Oral Contrast Agents, Gastrointestinal Diamagnetic Contrast Agents, Relaxivity, and Combination Oral Contrast Agents.
spacer

• View the DATABASE results for 'Gastrointestinal Superparamagnetic Contrast Agents' (6).Open this link in a new window

 
Further Reading:
  Basics:
Negative GI Contrast Agents
   by www.mritutor.org    
MRI Resources 
Stent - Corporations - - Stimulator pool - Calculation - Research Labs
 
Lumirem®InfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.MRI Resource Directory:
 - Contrast Agents -
 
Lumirem® belongs to the negative oral contrast agents (same as GastroMARK®, another brand name for ferumoxsil). Lumirem® is used to distinguish the loops of the bowel from other abdominal structures and physiology. When Lumirem® is ingested, it flows through and darkens the stomach and the small intestine in 30 to 45 minutes. By more clearly identifying the intestinal loops, Lumirem® improves visualization of adjacent abdominal tissues such as the pancreas.
Additionally, in Europe Lumirem® is approved for rectal administration to delineate the lower intestinal system.
Drug Information and Specification
NAME OF COMPOUND
Ferumoxsil (USAN, SPIO), AMI-121
CENTRAL MOIETY
Fe3+/Fe2+
CONTRAST EFFECT
T2*enhanced
r1=3.4, r2=3.8, B0=1.0T
PHARMACOKINETIC
Gastrointestinal
CONCENTRATION
52.5mg Fe/300mL
DOSAGE
300 mL oral
PREPARATION
Finished product
INDICATION
Bowel marking
DEVELOPMENT STAGE
For sale
DISTRIBUTOR
See below
PRESENTATION
Suspension of 300 mL
DO NOT RELY ON THE INFORMATION PROVIDED HERE, THEY ARE
NOT A SUBSTITUTE FOR THE ACCOMPANYING PACKAGE INSERT!
Distribution Information
TERRITORY
TRADE NAME
DEVELOPMENT
STAGE
DISTRIBUTOR
EU
Lumirem®
for sale
spacer

• View the DATABASE results for 'Lumirem®' (5).Open this link in a new window

 
Further Reading:
  Basics:
ferumoxsil, oral suspension GastroMARK GastroMARK ®
MATERIAL SAFETY DATA SHEET
   by dailymed.nlm.nih.gov    
MRI Resources 
Breast Implant - Implant and Prosthesis - Mobile MRI Rental - Examinations - - Spectroscopy pool
 
     1 - 5 (of 12)     next
Result Pages : [1]  [2]  [3]
 Random Page
 
Share This Page
FacebookTwitterLinkedIn

MR-TIP    
Community   
User
Pass
Forgot your UserID/Password ?    



How AI will impact MRI :
only diagnostics 
saving time 
reducing cost 
makes planning obsolete 
reduce human knowledge 
not at all 

Look
      Ups





MR-TIP.com uses cookies! By browsing MR-TIP.com, you agree to our use of cookies.

Magnetic Resonance - Technology Information Portal
Member of SoftWays' Medical Imaging Group - MR-TIP • Radiology-TIP • Medical-Ultrasound-Imaging • 
Copyright © 2003 - 2024 SoftWays. All rights reserved. [ 18 March 2024]
Terms of Use | Privacy Policy | Advertising
 [last update: 2024-02-26 03:41:00]