Medical Physics in General (1 Viewer)

STALDER

New Member
Joined
Mar 22, 2004
Messages
5
Location
Sydney
Hey i just thought that if everyone that was doing this elective pitched in we could have a place to go to ask questions cause this isn't a topic that has masses of info. lol
So my question... If anyone has any additional info. on CAT scans I would love it cause all I can come up with is paired info. with the CT scan as an ultrasound.
Nicole xox
 

za

Member
Joined
Mar 15, 2004
Messages
233
Location
middle east
Gender
Male
HSC
2004
these are straight from som1's notes from phys resources.
they seem to explain the process very well




• Soft tissue anatomy is not very clear with standard x-ray radiography. Clarity is markedly increased by using x-rays and computers together in computed axial tomography. The word tomography comes from the Greek tomos = slice, and graph = picture
• Computerised axial tomography is a non invasive technique that uses x-rays to produce images of various internal parts of the body such as the head, heart and abdomen.
• To produce a CAT image, the patient lies on a table that is able to pass through a circular scanning machine called a gantry (the table lies on the axis of the gantry hence the axial in CAT)
• X-rays from the gantry are fired at the organ being scanned and pass through the tissue. The degree of absorption – attenuation – depends on the tissue type that it passes through. Detectors measure the amount of x-rays that pass through. The gantry rotates around the patient and x-rays are continuously fired from different angles. The data is analysed by a computer using an algorithm to produce a cross sectional ‘slice’ on a video screen. The slice is collimated (focused) to a thickness between 1mm and 10mm using lead shutters in the front of the x-ray tube and detectors
• a series of slices can be made to build a picture of an entire organ or even the whole body
• Tomographic pictures are made up of the small square or ‘pixel’ each which can be given a grey scale value ranging from 1 (black) to 256 (white). CAT scans are capable of producing high resolution anatomical images
• CAT scans are used in an ever increasing range of diagnostic applications including the detection of cancerous tumours, infections, bone fractures and even blood clots. Contrast solutions such as iodine and barium sulphate can be added to improve contrast between the scanned organ and surrounding tissue
 

wahashtini

Member
Joined
Feb 17, 2004
Messages
52
WWLLLLLLLLLEEEEEEKKKKKKKKKKK HHHHHHHHAAAAMMMMZZZZZZZZZZZEEEEEEEEEEEEEEEEEEEE!!!!!!!!!!!!!!!!!!!
how'd u type up so much, A3JEBIIIIII
 

snoopwogg

Member
Joined
Feb 4, 2004
Messages
74
Location
Guantanamo Bay
Gender
Male
HSC
2004
they invented a little thing in the past few years called a mouse, right.. so then what you do is.. (this is so genius..) you cdrag you mouse of then information... all while having your magic little finger on the left button of the mouse.., then you let go.. and click on the right button... so then this little menu thingo pops up.. and you click on COPY.... and these computer hackers and stuff worked it out and then said you then right click where you want to put the informatioan and on that magic menu that pops up once again you click on PASTE... ITS THAT EASY! GENIOUS!!!! I DONT THINK EVEN EINSTEN COULDVE DONT IT...
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top