The part of the body to be X-rayed will be placed between the X-ray machiene, the radiographer will stand behind a led screen.
The X-ray produces ionisong beams which have a short wave length, they are sent through the body as an invisible beam, radiation is absorbed in different rates around the body.
More dense structures like bone will absorb more radiation so they will show up as white on the X-ray, and less dense areas wont absorb as much radition so they will show up darker.
The advantages are it is non invasive, it is good for detecting bone problems it is also quick cheap and easy to carry out.
The advantages are radiation can be dangerous and it doesnt detect problems with soft tissues.
The person will drink the contrast medium (barium meal), this is dense.
There is a period of waiting that is necessary for the barium meal to be digested by the stomach.
The contrast meal will be digested by the small and large intestines.
Hollow and fluid filled organs will show up as white on the X-ray.
The advantages of a contrast medium are that it is good for detecting problems with the soft tissue, and it is quick.
The disadvantages are that it is expensive and raditation can cause risks.
The person should remove all metal objects and lie on the table. The table slides into the scanner, the scanner than makes a loud noise and roughly takes 35-40 minutes.
The MRI uses electromagnetic forces which travel into the body, the hydrogen atoms align, a radiowave then stops themagnetic forces and the atoms fall down. The magnetic forces comes back and the atoms realign, when they realign they send off a radiowave which is converted into into an image on the computer, it is a 3D image with different levels of brightness.
The advantages of this is that it creates a good clear 3D image.
The disadvantages are that it is expensive, loud and it can cause anxiousness.
The patient will lye on the bed/table, and the scanner will slowly slide into the scanner.
At the same time as the scanner rotates it emits pulses of X-rays and catches whatever radiation has gone through the body.
information from a set of X-ray recievers is processed by computer software to produce an image in the form of a series of slices which then create a 3D image.
The advantages of this is that it produces a clear image which is three dimensional, whole body scanning is possible and it is painless.
The disadvantages are that the equiptment is large and expensive and there are health risks because of the radiation.
Radioactive isotopes EG carbon and nitrogen are combined with other elements which are specific to the part of the body that is being scanned.The radioactive isotope is introduced to the body by a drip, being swallowed or being injected, as the element is in the specific part of the body it emits gamma rays, more active areas of the body will take up more of the element so it will give off more gamma rays EG a cancerous areas.
And less active organs take up less of the element (damaged organs).
A gamma camera detects the gamma rays that are being emmitted from the part of the body, which are converted into an image by a computer.
The advantages of this is that it is good for detecting problems with tissues and organs.
The disadvantages of this are the health risks involved with raditation.
The patient lies on a bed/ table which slides into a scanner. The radioactive elements are mixed with elements that are specific to the body, they are introduced into the body by a; drip, being swallowed or an injection. The period of waiting is necessary for the elements to reach the specific part of the body. Once they have reached the body it emits positrons, more active areas will take up more of the element so more positrons are emitted (cancerous areas), less active areas will take up less of the element so less positrons are emitted (damaged organs).
The scanner measures the positrons that are emitted from the person.
The advantages are that it is effective when detecting pain damaged,and it is painless.
The disadvantages is that the equiptment is large and expensive, and there are health risks because of the radiation.
Lie down on a table/bed. Skin must be exposed. The area is covered with an oily gel to improve contact between the skin and the transducer. The transducer is slowly moved around the body.
High frequency sound waves are sent from the transducer directly through the skin and into the body. When the sound waves hit a structure within the body they will bounce back to the transducer. The sound waves produce an echo, which is converted into an electrical signal, which is converted into an image by the computer. Ultrasounds can be done internally e.g. vaginally.
Advantages: Safe-no radiation, Inexpensive ,Painless, Can see movement
Disadvantages: Images can be unclear , Not useful for brain scanning as they cannot penetrate bone
Skin is exposed. Electrodes are attached to the skin using sticky pads. They are placed on the chest, ankles and wrists.
The electrodes measure electrical activity of the heart, which comes before each heart contraction (heartbeat). A wave will be produced on a moving screen- a normal wave is a PQRST wave. Abnormal results will be interpreted by a trained cardiologist. ECG’s can be carried out while a patient is moving e.g. on a treadmill.
* Cannot detect what is wrong with the heart-further tests are required.
taking a live sample of tissues from the body for biochemical or genetic testing, the tissue can be removed by;
1. a needle- is used to draw tissue and fluid from a lump to be studied.
2. minor surgery- a drill is put into the skin and a sample of tissue is drawn out and cut away so it can be tested.
3. Endoscopy- a camera is used to reach inaccesible parts, it is inserted into an opening e.g mouth. a brush or minature forceps on the end of the endoscope will collect the cells/ tissues.
The tissue samples are examined by a cytologist, abnormal (cancerous cells) can be seen by them being placed under a microscope. This sample is often treated with staining agents to enable to less visible cells to show.
BODY FLUID SAMPLING.
- high levels of suger/ glucose indicates diabetes.
- high protein levels indicates infection
- a low red blood cell count can indicate anaemia
-high levels of glucose in the blood can indicate diabetes.
Advantages- quick and easy
Disadvantages- futher tests are often needed