What is the CT check?What should I pay attention to when doing inspections?

CT room waiting hall, especially in the morning, there are always many people, the patient lined up is anxious.

CT room inspection technicians, explaining inspection precautions to patients, etc., repeatedly speaking in a word, the throat is smoking, or I have to say.

The CT room diagnosed a doctor, always wrote an endless examination report, rare cases that could not be seen, and sometimes they could not drink a glass of water in the morning.

The CT room is busy and tired, and occasionally quarrels in doctors and patients.

The CT checking time is relatively short, which can solve many problems in clinical. Generally speaking, CT is popularized in various hospitals.

How much does the public know about CT checking? The following is a brief introduction:

What is CT?

CT is the abbreviation of X-Ray Compute Tomography. It was born in 1967 and was developed by British engineer Godfleyn.hounsfield and was applied to the clinic in 1972.

The CT structure mainly includes three major systems:

① Data Acquisition System (DAS); DAS;

② Image reconstruction system;

③ Image display and saving system.

Coupled with the central system controller, it constitutes a complete CT. The structure is shown in the figure:

The image of the CT device collection and reconstruction is composed of a certain number of pixels with different grayscales of black to white according to matrix arrangement. The grayness of the pixel is reflected by the detection of the detector after the X -ray is attenuated through the attenuation of the human tissue organs.

X -ray attenuation? The X -ray is essentially electromagnetic waves, which causes intensity attenuation during the spread and material. Like light (such as the sun), the spread in the air is decreased, and the density objects (such as the wall) cannot be worn, and the refraction occurs. It is black, the human bone has a high calcium density, the X -ray is not easy to pass, the image is white, the density of human liquid and soft tissue is between the two, showing different gray. The CT image is a horizontal facade image image, which is overlapping without the front and rear images, and is not disturbed by the tissue outside the level

Are all CT images the black and white gray images of the horizontal layer? NO! NO! CT horizontal layer original image can be rebuilt different images required by special software, such as CT arteries on the head and neck

Vascular image (VR diagram):

For example, brain CT irrigation image (color):

CT, how many people do?

1. Wide -checking indications, including the brain, head and neck, chest, abdomen, pelvic cavity, spine, limbs and joints, hearts, etc.

2. There are various types of CT inspection methods, including flat scanning, special scanning technology (thin layer scanning, target scanning, high -resolution scanning), enhanced scanning, CT blood vessel imaging, CT irrigation imaging, CT energy imaging, CTA -oriented puncture biopsy and Treatment, etc., and multiple image post -processing technology (multi -plane restructuring, curved restructuring, volume reproduction, simulation endoscopy, etc.).

3. The scanning speed of multi -layer spiral CT (now the hospital is basically multi -layer spiral CT) has increased significantly, the image resolution is increased, the utilization of X -ray is increased, the exposure is significantly reduced, and the corresponding radiation of the human body is also reduced.

How to check the whole body CT?

Don't worry, although the CT examination is suitable for the whole body, the organizational structure of each part of the human body is different, the scanning methods are different, and the relevant preparations before scanning are different. Sometimes special examination methods should be selected according to the disease conditions and clinical doctors. How to check the CT examination, you have to listen to the clinician.

Preparation before CT examination:

1. For general inspections, the corresponding parts of metal items should be removed, such as the head of the head and earrings.

2. For abdominal examinations, intestinal preparation should be performed. There is no oral tadpole within a week. Water is fasted within 4-6 hours before the examination. The chest and abdomen examination should train inhalation screen gas, scan the pelvic CT, and urinate 1 hour before examination, medium degree.

3. Cardiac inspection must be trained.

4. Those who cannot cooperate can be checked after the method of sedation or anesthesia. The personnel need to be accompanied by the personnel of the clinical relevant departments for patients with severe patients, and real -time monitoring and treatment of changes in the condition.

CT inspection precautions:

1. Special groups such as pregnant women, pregnancy preparation, and children are not recommended for CT examination.

2. During the examination, the body is required to remain quiet to ensure the accuracy of the test results. Just like taking a mobile phone in life, if the photo is moved, the image will be blurred.

3. Use iodine contrast agent to check patients (such as enhanced examination, vascular imaging, etc.), first determine whether there is a contrasting agent allergy, accompanied by family members and signed. Those with hyperthyroidism, iodine -containing reagent, and kidney dysfunction are incomplete. It is not recommended to check the iodine -containing comparison agent. After the inspection, observe for half an hour, and then leave the CT room after confirming the symptoms of no discomfort.

4. Under normal circumstances, CT examination does not require family members to accompany the inspection room, but in the case of children, elderly people, enhanced scanning, etc., family members still need to be accompanied by the inspection room to avoid accidents. Clothing and far from the machine.

Is the CT room waiting hall safe?

There is no radiation in the CT room waiting hall, which is safe.CT computer rooms are constructed in accordance with the "Basic Principles of Radiation Sanitation Protection", the main protection (wall surface) of the computer room has the thickness of 2㎜ lead, and generally 24㎝ thick solid brick walls, as long as the mortar is full, no gaps can be reached 2㎜Lead equivalent, the door of the machine room is a special lead door, and the professional testing department regularly conducts protection effect detection.Is there a film for CT check?

Traditional physical films need to wait for the film after checking, and then give it to the doctor to watch it.Electronic film (cloud film) is to store and read the traditional physical film to electronic film. After the examination, there is no need to wait for the film. After the examination, the doctor can watch the image on the computer and save time to see a doctor.

Author Nie Qing executive technician Funan County People's Hospital Imaging Department

[Reminder] Pay attention, there are a large number of professional science sciences here to reveal those things about surgical anesthesia ~

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