The spectrum of computed tomography applications is diverse. Bones are particularly good, which is why CT is excellently suited for the diagnosis of bone fractures, signs of wear, osteoporosis (CT bone density measurement) or a herniated disc. But also tumors, bleeding, accumulations of water, cysts, abscesses and inflammation are easy to see. But what exactly is being investigated?
CT: What is being investigated?
We examine skulls (CCT = cranial computed tomography), neck and shoulder region, chest and lungs, abdomen, pelvis, spine, peripheral bones and joints. Vessels (CT angiography) can be easily visualized by previously giving contrast agents by mouth or by syringe. This is used, for example, as perfusion CT in the early diagnosis of strokes or in the presentation of the coronary arteries. In the latter case, the extent of arteriosclerosis can also be determined (coronal calcification).
For early detection of bowel disease and for the clarification of abdominal discomfort can serve virtual colonoscopy, a CT scan that simulates a journey through the colon with an endoscope. However, to what extent it is equal or even superior to conventional colonoscopy is still being discussed.
Disadvantage is that no tissue samples can be removed, the advantage that also surrounding structures can be assessed in the same examination. Many patients find the carbon dioxide gas introduced by the anus to develop the intestine unpleasant; however, even an inserted tube is not exactly comfortable.
In addition to sonography, computed tomography is also used to visually inspect tissue samples (for example from the liver) and withdraw fluid collections (CT-guided biopsies) or to inject narcotic drugs (for example, severe bone pain).
How does computer tomography work?
The device is in a separate examination room. The patient lies flat on a couch and is thus pushed into the opening in the middle. The couch slowly moves forward during the examination. The patient should be as relaxed and calm as possible. He has contact with the attending staff via an intercom and may be instructed to hold his breath, for example. The duration of the examination depends on the area examined and the type of procedure.
The duration of a CT is usually between 10 and 30 minutes. Sometimes preparations are necessary - for example, the patient may not eat anything bloating before examinations of the gastrointestinal tract. Contrast agent is usually administered one to two hours before.
CT: What are the advantages and disadvantages?
The actual CT examination is painless. Disadvantage, however, is that the radiation exposure is higher than in conventional X-ray. Depending on the size of the scanned area, the type of tissue and the thickness of the tomograms, it can be a multiple of the natural annual radiation dose. However, the benefits outweigh - assuming responsible and targeted handling as well as avoiding double examinations.