This question, everyone cares about two things:

The first point is the radiation angle. Is it possible to do lung CT if you do too much?

Second, the angle of finding lung cancer. How often do lung CT to help us find early lung cancer?

Below, I will talk to you about lung CT from the above two points.

Let's look at the first point, about CT radiation in the lungs. First of all, do we say that lung CT has radiation? I think everyone knows this. As long as the lung CT is taken, there must be radiation.

Why?

You may have no objection to x-rays and chest x-ray radiation. But some people still don't know much about lung CT.

In fact, the radioactive source of ct is also X-ray!

Then let's say this is also X-ray exposure. Why are there two kinds of examinations, X-ray and CT? Sometimes even some patients will have a CT scan after the chest X-ray.

Why is this?

In fact, this is the difference between X-ray and ct. You can understand it this way. We regard our chest as a piece of bread. When we take X-rays, we actually press the bread on the chest into a whole piece.

CT is different. It's like cutting the "bread" of our chest layer by layer with a knife and making many "slices".

Obviously, you can see more clearly by taking CT because there is no overlap. It shows us a cross-sectional image, showing it to us layer by layer, so that we can see it more clearly and have higher density resolution. One is ten times higher than our chest radiograph. Therefore, CT can display the detailed information of our lesions more completely and thoroughly.

So sometimes our doctors will ask patients to have a ct scan after taking a chest X-ray, because sometimes problems are found or suspected after taking a chest X-ray, but we can't 100% confirm and diagnose, so we will choose a clearer CT at this time.

Why not just do CT?

First, CT is more expensive than X-ray;

Second, some diseases can be diagnosed by taking an X-ray without excessive medical treatment;

Third, from the perspective of radiation, everyone thinks that taking CT is equivalent to taking several X-rays, and naturally taking CT radiation is better than taking X-rays!

So according to this, CT radiation is relatively strong, and how often is it appropriate for people to do it?

First of all, the CT radiation we are talking about is relatively strong, especially X-rays. Taking a CT is equivalent to taking 300 chest radiographs, but this does not mean that our CT radiation dose is unlimited!

For example, in our country, 0.3 mGy is required for chest X-ray and 8 mGy for CT scan, but this is not necessarily the case, depending on your shooting position and specific lesions.

Now our CT machine has made great progress, and the shooting dose can be controlled by the automatic dose control of mA. For example, if some parts are thicker, we will increase the dose and the radiation will definitely be greater; Where there is air in our lungs, where there is a lot of air, it is easy to penetrate and will automatically decrease a little. Through this technology, our CT examination is actually not as terrible as everyone thinks. After using this technology, the dose is greatly reduced, and basically it is 4-5mGy once!

How often is it better to do it?

Although CT radiation has dropped a lot, it is equivalent to taking a chest X-ray of 100, so from a health point of view, we suggest using CT scientifically!

For example, if you have a physical examination, we can do it once a year, but if you find something wrong, we can do it twice a year.

However, if you say that you really need to diagnose and treat diseases, then it is wrong for us to insist that CT radiation is harmful and that CT should be done once a year. At this time, we must weigh the pros and cons, because there are many diseases that cannot be seen once or twice. We must observe dynamically to see if there are any changes. For example, the most common pulmonary nodules must be followed up regularly, and sometimes they may be photographed once a year. There is also the cancer patient we are talking about, who is doing chemotherapy and may have to take pictures every other month!

Therefore, from the perspective of radiation, it is better to take a CT scan of the lung. It must be determined according to the purpose of your examination and the needs of disease diagnosis and treatment. It doesn't mean it has to be once a year or no more than twice a year.

Then, let's look at the second point. From the perspective of finding lung cancer, how often do we do lung CT to help us find early lung cancer? First, can lung CT detect lung cancer? What kind of results should we pay attention to? Could be lung cancer.

The answer is definitely possible! As I said above, lung CT has two advantages: one is layered display without overlapping, and the other is high density resolution. So basically, we can see lung diseases, and we can show diseases such as inflammation and tuberculosis, including tumors. But lung cancer can't be diagnosed, and further examination and biopsy are needed to diagnose it!

What kind of result, we should pay attention, may be lung cancer?

As we all know, the tumor is basically a nodule or a spherical shadow, which is a common contour, and then it depends on the specific shape, that is, whether the nodule will have such burrs.

Or such a foliation mark

There will still be pleural traction

Moreover, such bronchial signs and so on.

These are actually common malignant features of nodules. The more malignant, the greater the possibility of lung cancer!

So how often is it better to shoot?

Again, it depends on the specific situation, and the most important thing is to look at the result of your last filming. Therefore, the CT films taken at ordinary times must be kept well, and you should take them with you every time you go to see a doctor. Only by comparison can our doctors make a better judgment!

If you just go for a physical examination and do a CT scan of the lung for the first time to see if there is lung cancer, then if the result is normal, it will be fine to check it once a year!

But if you say that you have found pulmonary nodules, we don't mean that once you see a patient with pulmonary nodules, you suggest that he have a CT scan every month. There is scientific guidance for doing this intensive examination.

For example, your lung nodule is only a nodule less than 6mm, so don't worry too much. Just check once a year or start taking pictures once every six months, but nothing has changed. Just look at it when you have a physical examination once a year!

However, if you are a high-risk group of lung cancer, it is recommended to review it every 3-6 months. Then, according to this result, a professional doctor will tell you whether it is necessary to continue the reexamination and how often to take photos in the future. This requires professional advice, not what you want!

To sum up, for early CT screening of lung cancer, it must be a process of filming, finding problems, rechecking, and then judging according to the rechecking results, and then deciding how often to shoot again. Everyone's follow-up schedule is different, because nodules are likely to be different, some may be solid, some may be sub-solid, and some may be ground glass, so we must treat them differently.

At the same time, it doesn't mean that the reexamination will be fine, and these nodules don't have to be taken care of. For example, some high-risk nodules mentioned above have not changed. Sometimes, in order to prevent accidents, we occasionally do some evaluation and then do a relatively active surgery!

Everyone must remember that there are two doors that can block lung cancer. One is to quit smoking. The other is our lung CT screening!

Regarding lung CT and lung cancer, you can leave a message below if you have any questions. I insist on using the words you can understand and the most original code words to bring you the best, most comprehensive and practical health science. If you think it's good, you can pay attention to Medical Detective and forward it to benefit more people around you!