Computed Tomography

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Basic Working Principle Of CT Scan

It is as simple as passing X-rays through the patient and obtaining information with a detector on the other side. The X-ray source and the detector are interconnected and rotated around the patient during scanning period. Digital computers then assemble the data that is obtained and integrate it to provide a cross sectional image (tomogram) that is displayed on a computer screen. The image can be photographed or stored for later retrieval and use as the case may be.

X-rays are electromagnetic waves. The main reason why X-rays is used in diagnosis is because all substances and tissues differ in their ability to absorb X-rays. Some substances are more permeable to X-rays while some others impermeable. Owing to this difference, different tissues seem different when the X-ray film is developed.

Dense tissues such as the bones appear white on a CT film while the soft tissues such as the brain or kidney appear gray. The cavities filled with air such as the lungs appear black.

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This is such a "nice" description. A more realistic desrciption is the machine is a huge monstrosity and very very noisy. Additionally, you forgot to mention a HUGE negative about these machines, once you get rolled in, the machine is literally abouit 1 inch from your entire body - on all sides. You can't move at all! If you are unconfortable in small places you will freak out! 10-15 minutes is IF it goes perfectly. Mine took about 30 minutes as she keep getting mad because I coughed or breathed or ever so slightly moved. It was by far the worst experience. Also, the machine gives off so much radiation, the tech stays outside the room. That is not comforting.
normalguy Thursday, January 03, 2013
CT scans on average take only a couple of minutes. From your description, it sounds like you had an MRI. MRI uses radiofrequency waves with a strong magnetic field to produce images, not radiation. MRI’s also take much longer and are typically very confining compared to a CT. If you are unable to hold still, the procedure will be prolonged due to the motion distorting the images. In addition… radiology technologists are exposed to radiation every working day of their lives so you cannot blame them for leaving the room, plus the consol to control and run the machine is outside the room.
Roentgen Wednesday, April 10, 2013
you have to ask first before you complain.
Niel14 Monday, June 03, 2013
computed tomography is brillant for the students and teenagers.it is very helpful and gives us plenty of knowledge about any matter.
abhinav2011 Saturday, January 29, 2011

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