Contrast media agents used to better the imagination of variety meats in a similar scope of contrast radiography.A Contast technique provides elaborate organic structure size, form, place and internal parts.A In some instances, appraisal of organ maps allowed.
Ideal material difference must be:
a ) Inert
B ) Non-toxic
degree Celsius ) to go on for a long clip
D ) is simple and wholly eliminated from the organic structure
vitamin D ) depression
F ) has a different soaking up of a series of involvement
A A Contrast agent in medical nomenclature, is defined as exogenic substances that are used to increase the visibleness of the construction or fluid in the body.A Exogenous substances to alter the contrast in X-ray images with X-rays affects fading, leting the visual image of anatomical constructions non easy seen,
a ) Blood vass
B ) kidney,
degree Celsius ) Dyskinesia / liver channel
SchopnosA? contrast agent to cut down the X ray based on the cardinal fact that this substance was introduced into the organic structure becomes both an atomic figure higher or lower than the environing tissue ( this is the figure of atoms of each substance that determines how much radiation will weaken )
By accident of history since 1986, the first successful arteriography performed at the custodies amputated.
A A A A A contrast medium consisting a suspension of calcium hydroxide in the H2O injected into the arterias of the body.A The first 1 in the H2O soluble I contrast media used in 1920 and met for the patient enduring from pox in those yearss was treated with Na iodide.
A A A A The Na iodide tummy as seen in the image “ to increase the denseness ” of the kidney.A Sodium iodide, nevertheless, has a high toxicity when used as contrast media
A A A A A A A figure of research in radiology will necessitate system disposal of contrast into the organic structure through a vena or artery.A An illustration is normally an endovenous urogram.There are two types of I incorporating contrast media:
a ) Onic
B ) Non-ionic ( in relation to chemical construction )
A A Normally, merely the bone, and air, and positions on field skiagraphy ( x-ray ) .A To exemplify the manner pebglihatan piss or blood flow in blood vass of contrast media, which contain I are introduced to increase the denseness of the piss or blood.A They will look in colour “ white ” in the movies, such as your castanetss on X ray ) .
A substance used to illuminates certain constructions that would otherwise be difficult to see on the radiogram ( movie )
Substance placed in the organic structure to supply added contrast when capable contrast is low. Increase the radiographic contrast between the countries incorporating the CM & A ; countries non incorporating Contrass media ( CM )
Why do we necessitate contrast? ?
Artificially increase capable contrast in organic structure tissue and countries where there is small natural topic contrast.
Example abdominal entrails have really small natural topic contrast
really hard to place specific organ
really hard to separate one organ from another
Factor set uping contrast media
– as concentration of iodine addition, the viscousness thickness addition
– as temperature addition viscousness lessening
Rate of injection
– as the rate addition, the concentration in the blood increased-resulting in a more evident physiological consequence.
Categorization of reaction
– nasal stuffiness
– laryngeal hydrops mild
– laryngeal hydrops ( terrible )
Types of Contrass media
Contrast media can be loosely grouped into two classs
Positive Contrass media
Non I based
Negative Contrass media
Different types of Contrast Media ( Ionic & A ; Non Attic ) The schemes above about managing H2O solubility:
a ) chemo
B ) osmotoxicity
hold led to four different types of I contrast media for urography, angiography and
( I ) Ionic monomeric contrast media
( two ) Ionic dimeric contrast media
( three ) Non-ionic monomeric contrast media
( four ) Non-ionic dimeric contrast media
As the ability to polish the atomic I X raies are free of organic
molecules are chemically bound, the ratio between the side effects:
a ) toxicity,
B ) osmolality
degree Celsius ) Viscosity
vitamin D ) monetary values of different contrast media should ever be made in the iodin equivalent to the amaunt and concentration.
A ( This is of import because it is related to side effects ;
monetary values, etc. , with the consequence of the coveted consequence of a contrast media, viz. its X-ray fading, which is comparable to the sum of I.
A A A A
A A A A In general, a positive contrast media are those that have increased
soaking up ( fading additions ) X ray, and seen as white / grey, while countries
negative contrast are those who have less soaking up ( lower fading ) of X raies and look as dark countries / grey.
Principles of contrast
Contrast is the difference in radiographic optical denseness of the radiograph.A denseness or denseness on radiogram made at 50-70 kilovolt is relative to the square of the atomic figure of the web under scrutiny.
A A A A Contrast media can be divided into positive and negative contrast agents.A Positive contrast agents have a higher atomic figure of the web:
Barium = 56.
Iodine = 53.
Bone = 14.0.
Soft tissue = 7.4.
Fat = 5.9.
Lead = 82
Negative contrast agents are comparatively radiolucent due to low specific gravitation. Before executing any contrast survey plain radiogram must be taken to place lesions that may be masked by contrast disposal, eg radioopaque foreign organic structures which may be masked by Ba disposal.
Hazard Contras Media
Grant of contrast stuff is normally rather safe. However, injection of any sort will convey little unsafe hazard including:
a ) hurt to the nervousnesss
B ) vass arteria ( arteria ) or venas ( vena )
degree Celsius ) redness ( infection )
vitamin D ) an allergic reaction to the injected stuffs.
Injured blood vass will do escape of contrast stuff into the environing musculus tissue / tissues ( Extravasation ) . This hazard was estimated in 0.04 % to 1.3 % .Other hazards / complications of the injection of contrast stuff particularly allergic reaction, and may include:
Mild reactions such as the organic structure feels:
a ) Warm ( flowers )
B ) Sneezing
degree Celsius ) Itch of ruddy musca volitanss
vitamin D ) puffiness ( urtications )
vitamin E ) Vomiting
degree Fahrenheit ) concern
( A small dizzy with the feeling like purging that will vanish in a few proceedingss )
For the basic I contrast stuff is injected to press gustatory sensation in oral cavity, bad breath out of kinds and organic structure feels warm in the lower venters ( pelvic ) andon the dorsum of the pharynx.
Rarely a stronger reaction such as asthma ( Asthma ) , daze ( daze ) and ictuss ( paroxysms ) .
Emergency supplies are available for events this rare
Death in highly rare instances, approximately 1 in injection of 250,000 to 400,000 ( 0.0004 % ) .
Although less than 1 % injected dose absorbed into the ASI ( Air Susu Ibu ) , suckling isrecommended that patients stopped breast eating ( breast milk ) for 24 hours afterinjection and discard chest milk after injection of contrast.
Radiographic contrast stuff
Contrast stuffs are compounds used to better visual image ( visibleness ) on the internal constructions of a medical diagnostic imagination. Contrast stuff used in the X-ray imagination to better X-ray fading ( positive contrast stuff ) that will be discussed here or greater cut down the power of X-ray fading ( negative contrast stuff with air base or gas ) .
In add-on to the contrast stuff is besides used in analyzing MRI ( Magnetic Resonance Imaging ) , but this method is non based on X raies, but vary magnetic belongingss of the H karyon absorbs the contrast stuff. Materials Such contrast MRI with Gadolinium is:
a ) Barium sulphate
Barium sulphate, a white pulverization that was indissoluble. This pulverization is assorted with H2O and some extra constituents to do the mixture contrast.
This stuff is by and large merely used in the digestive piece of land, normally ingested or given as an clyster. Upon scrutiny, this stuff will come out of the organic structure along with the fecal matters.
B ) Iodine contrast stuff
Iodine contrast stuff can be bound to organic compounds ( non-ionic ) or a ionic compounds. Ionic stuffs was foremost made and is still widely used to depend on the intended review. Ionic stuffs have side consequence profile is worse. Organic compounds have side effects because there are fewer molecules berdisosiasi the constituents.
Many of the side effects caused by the hyperosmolar solution which is injected, which These substances lead to more iodine atoms per molecule. The more I, so coerce X-ray fading additions. There are many different molecules.
Media I based contrast to H2O soluble and non harmful to the organic structure. Contrast stuffs are widely sold as a solution of clear, colourless liquid. Concentration is normally expressed in milligram I / ml. Modern teriodinasi contrast stuff can be used in about all parts of the organic structure.
Most of them used endovenous, but for different intents can besides be used in intraarterial, intrathecal ( spinal ) and intraabdominally – about the full organic structure pit or a possible infinite.
degree Celsius ) Chemical composing
Based on the phases of its development, form and chemical composing of the contrast media:
Before 1950 In this period, all ionic contrast media is iodine, which in arrangement.There is a chemical ion. Ions composing the contrast media consist of:
Mid Year 1950, get downing mid-year 1950 established the molecular footing of the usage of benzoic each molecule binds three atoms of I. At this phase the development of shared becomes:
= Ionic Contrast Material
Ions composing contrast media cations that consist ( +ve charge ) and anions ( -ve charge ) ions. Cations bound to the acerb extremist ( -COO- ) concatenation pealing C1 benzine.
Cation besides gives the features of contrast media, in which each type give different features to each other. There are several sorts of cation.
The usage of contrast media, including:
* Sodium ( Natrium )
The nature of the Na in contrast medium was reduced viscousness ( viscousness ) , and fewer anaphylactic reactions caused by cut downing substances mnuculnya histamine that cause allergic reactions. On the other manus is more sodium corrosive of cells endothelium and parenchyma of certain variety meats, doing it more toxic of other substances.
* Meglumine ( NMG, N-Methylglucamine )
Meglumine have toxic belongingss are smaller than Na, but meglumine diuretic consequence ( cut downing the concentration of I in the piss ) .
In the acid type and concentration of meglumine less the same cause addition in blood force per unit area, bradycardia, and paroxysms than Na.
These substances have belongingss that are non owned by Na meglumine maupub, is non hold toxic belongingss and has a low viscousness, but this substance vasodilatation cause strong plenty.
In add-on to the above stuffs are sometimes besides used cation of Ca ( Ca ) and Mg ( Mg ) . To obtain the coveted belongingss of contrast media in radiology pemeriksann normally done some combination of several types of cations in a types of contrast media.
= Ionic Contrast Material Monomer
Monomer ionic contrast stuffs is a signifier of ionic contrast stuff that has one ring in a molecule of benzoic acid.
= Ionic Contrast Material dimmer
Ionic contrast media is holding two rings of benzoic acid in one molecule. One illustration of the form and chemical composing of this type of contrast stuff is Oxalate ( Hexabrix ) which is the first demerit ionic contrast media made:
* Non-ionic contrast stuffs.
Du the chemical composing of non-ionic contrast media have non found the being of ionic bonds between the atoms composing the molecule.
If the ionic contrast media, there are two penyususn molecular atoms ( cations and anions ) in the non-ionic contrast stuff There is merely one atom that has a molecular concept its ain features.
+ Non-ionic contrast stuff Manome
Contrast stuff was derived from an ionic monomer contrast media, which is the replacing the carboxyl group by a extremist group that is non-ionic amide ( -CONH2 ) .
+ Ingredients Non-ionic dimeric contrast
Formation of the chemical construction of contrast stuff through the procedure of replacing the group carboxyl dimmer ionic contrast media every bit good as by groups of non-ionic groups, which in kahir sisntesa produce I to particle ratio contrast media 6: 1.
vitamin D ) Osmolality
The concentration of active molecules that provide the solution osmotic force per unit area, so provide the capableness of a dissolver ( H2O ) through a membrane. To put with milliosmol per litre ( osmolarity ) or milliosmol per kg H2O ( H2O ) in the 37oC ( osmolality ) .
Osmolality was non influenced by atom size, but its value depends. The entire atom concentration and I. Ionic contrast stuff has a figure of atoms greater than non-ionic contrast stuff because of the ionic contrast media are two atoms ( cations and anions ) to two times higher osmolality.
OSMOLALITY ( m 0sm/Kg ) = mgI/ml. K.G
vitamin E ) Side Effectss
Iodine contrast stuffs that modern medical specialties are safe reactions unsafe could go on, but non common. The chief side effects are anaphylactic reactions and nephropathy.
Anaphylactic reactions are rare, but can happen as a response to the contrast stuff is injected or given via unwritten and rectal pyelografi and even decline. Symptoms are similar to anaphylactic reactions, but non caused by IgE mediated immune response. Patients who have a history of reaction to contrast, at high hazard for sing reactions anaphylactic.
Anaphylactic reactions runing from urtication and can rub, until bronchospasma and facial and laryngeal clyster. For instances of moderate and urticaria itchiness. Benadryl ( Diphenhydramine ) through the oral cavity or IV ( endovenous ) can be given. For reactions are more terrible, such bronchospasma and cervix or facial hydrops can be given hypodermic or epinephrine IV or albuterol inhalator, add Diphenhydramine may necessitate. If respiration is affected, the air passage should be released.
Nephropathy caused by Contrast Medium
Contrast media kidney disease could be caused by both the addition in blood keratinise degree greater than 25 % .
There are three factors associated with increased hazard of nephropathy is influenced by the contrast medium, nephritic upsets are diabetes, and intravascular volume is reduced.
Osmolality contrast stuff is believed to play an of import function in nephropathy. Ideally, contrast stuff should iso-osmolar of blood. Iodized contrast stuff that modern typically non Attic, ionic types of old-type common cause harmful effects over and non used once more.
To minimise the hazard of contrast medium nephropathy as a consequence, the assorted actions could be done, all of which have been analyzed in a meta-analysis are:
The dosage of contrast media should be tried every bit low as possible, although still able to carry on reviews added.
Non ionic contrast stuff
And nonionized contrast media iso-osmolar. One of controlled tests Random discovered that a substance iso-osmolar nonionized contrast is better compared to non-ionic contrast media of low-osmolar.
Hydrasi endovenous fluids with a salt solution.
Intravenous fluid hydration with saline solution plus Na hydrogen carbonate.