Does Full-Body CT Scan Increase Cancer Risk? Understanding the Concerns
The relationship between whole-body computed tomography (CT) scans and cancer risk? Hello, doctor. Ten years ago, I went to the emergency room at Mackay Memorial Hospital due to abdominal pain of unknown origin. They administered a contrast agent into my body (which later caused ...
Dr. Sun Shengyi Reply:
In theory, any radiation exposure increases the risk of developing cancer, although the majority of doses are negligible. Based on your description, it seems you received a contrast agent (likely via intravenous injection), which suggests a total body computed tomography (CT) sca...[Read More] Does Full-Body CT Scan Increase Cancer Risk? Understanding the Concerns
Understanding Radiation Exposure from CTAP and Other CT Scans
Radiation dose of CT angiography (CTAP) The radiation dose for a computed tomography angiography of the portal vein (CTAP) is approximately 10-20 millisieverts (mSv). For abdominal CT scans, the radiation dose typically ranges from 5 to 15 mSv per scan. A low-dose CT (LDCT) scan ...
Dr. Sun Shengyi Reply:
A standard abdominal computed tomography (CT) scan typically has an average dose of about 8.0 mSv (millisieverts). For a CT angiography of the upper abdomen focusing on the liver and spleen (CTAP), additional scans may be performed at different times, and due to variations in bod...[Read More] Understanding Radiation Exposure from CTAP and Other CT Scans
CT Scans for Liver Tumors: Radiation Risks and MRI Alternatives
Liver CT scan Hello Dr. Sun, I recently had an ultrasound during my health check-up that revealed a liver tumor. The doctor has arranged for a CT scan. I would like to know if the radiation exposure from the CT scan poses a cancer risk for my future, or if I can opt for an MRI in...
Dr. Sun Shengyi Reply:
The radiation dose from computed tomography (CT) scans of the liver can vary significantly depending on different factors such as the number of scans, body composition, and the scanning area, with an average dose of approximately 14.0 mSv (ranging from 8.0 to 21.0 mSv). This dose...[Read More] CT Scans for Liver Tumors: Radiation Risks and MRI Alternatives
Concerns About Excessive X-Ray Exposure: What You Need to Know
I have taken too many X-rays within a year and am concerned about the radiation dose being too high? Hello Doctor: Earlier this year, around February, I started experiencing frequent shoulder and neck pain, feeling uncomfortable no matter how I lay down. I suspected it might be r...
Dr. Sun Shengyi Reply:
Ms. Liang underwent a total of six spinal X-rays. The lumbar spine images had a higher dose, with two lateral views approximately 1.5 mSv (millisieverts), while the cervical spine images totaled about 1.0 mSv for four views. Currently, the equipment is very effective in controlli...[Read More] Concerns About Excessive X-Ray Exposure: What You Need to Know
Assessing Radiation Exposure from Thyroid Scans and Mammograms
Radiation doses from thyroid scans, ultrasounds, and mammograms? Hello Doctor: After giving birth, I discovered hyperthyroidism along with a thyroid nodule. The doctor wants to determine if this nodule is functional. In March, I underwent a technetium-99m thyroid scan, followed b...
Dr. Sun Shengyi Reply:
The radiation dose received after a thyroid scan varies significantly depending on the amount of the injected isotope and the duration of its retention in the body. The use of isotopes for examination involves a very low dose with prolonged exposure (unlike the single exposure fr...[Read More] Assessing Radiation Exposure from Thyroid Scans and Mammograms
Concerns About Radiation Exposure in Aging Dogs: What You Need to Know
Computed Tomography (CT) radiation Dear Doctor, My small dog is currently 15 years old. Four years ago, due to pectus excavatum, he underwent a chest CT scan (the doctor showed us two 3D images of the sternum). We later learned that the radiation dose is quite high. Additionally...
Dr. Sun Shengyi Reply:
The radiation dose from a routine chest computed tomography (CT) scan is approximately 7 mSv (millisieverts). However, the dose used for children and adolescents is typically lower. If the scan is focused solely on the bones and does not involve the injection of contrast agents, ...[Read More] Concerns About Radiation Exposure in Aging Dogs: What You Need to Know
Understanding Radiation Exposure from Dental and Chest X-rays
Radiation exposure issues? Hello, doctor. I have undergone a dental implant evaluation and had full mouth X-rays and dental cone beam computed tomography (CBCT) taken at three different clinics in early May, late May, and late June. Recently, I learned that my company requires a ...
Dr. Sun Shengyi Reply:
The radiation dose from a full mouth X-ray is approximately 0.02 mSv (millisieverts), while a dental computed tomography (CT) scan is about 0.08 mSv. A frontal chest X-ray is around 0.02 mSv, and a lateral chest X-ray is about 0.04 mSv (the lateral dose is indeed higher). Therefo...[Read More] Understanding Radiation Exposure from Dental and Chest X-rays
Comparing Low-Dose CT and Dual-Energy CT for Lung Scans
Computed Tomography (CT) Scan Regarding lung computed tomography (CT) scans, I have the following questions: 1. What are the differences in accuracy and radiation dose between low-dose computed tomography (LDCT) and dual-source dual-energy computed tomography (DSCT)? 2. I had a...
Dr. Yang Jinghua Reply:
Dear Mr. Hsiao-Ming, Regarding the two examinations you mentioned (lung and cardiac CT scans), the implementation of Low-Dose Computed Tomography (LDCT) in our country falls under the category of health check-ups. When performed using a dual-source CT system, the radiation dose ...[Read More] Comparing Low-Dose CT and Dual-Energy CT for Lung Scans
Does a Coin in Your Pocket Affect MRI Brain Scan Results?
MRI of the brain shows a coin in the chest pocket? I underwent a brain MRI and found coins in my chest pocket when I finished, but I didn't feel anything during the examination. Will this affect the interpretation of the results?
Dr. Wang Yifen Reply:
Having coins in the pocket of the examination gown likely indicates that the patient did not change into the appropriate examination attire before entering the MRI room. Whether this will affect the interpretation of the results depends on the imaging outcomes, which can only be ...[Read More] Does a Coin in Your Pocket Affect MRI Brain Scan Results?
Does Hip X-Ray for My One-Year-Old Affect Future Health?
My baby is one year and one month old. Will having a hip joint examination affect their future health? Hello doctor, my baby is one year and one month old. A few weeks ago, we went to National Taiwan University Hospital for hip X-rays, where four images were taken: three from the...
Dr. Sun Shengyi Reply:
For a one-year-old baby, the radiation dose from a single pelvic X-ray generally does not exceed 0.01 millisieverts, and taking four X-rays is unlikely to have any impact on future health. However, since radiation exposure is cumulative, unnecessary imaging should still be avoide...[Read More] Does Hip X-Ray for My One-Year-Old Affect Future Health?
Radiation Therapy for Stage II Breast Cancer: Key Questions Answered
Radiation therapy Dr. Sun: Hello! I have two questions I would like to ask you. Thank you for your answers. 1. After a local excision for stage II breast cancer, is it possible to choose not to undergo chemotherapy? Since the lymph nodes are clear, the doctor mentioned that I c...
Dr. Sun Shengyi Reply:
I apologize! For the treatment of breast cancer, it is best to consult a breast surgeon (as most cases require surgical intervention) or a medical oncologist. For aspects related to radiation therapy, you may consult a radiation oncologist. Cancer treatment often requires a multi...[Read More] Radiation Therapy for Stage II Breast Cancer: Key Questions Answered
Impact of Frequent X-Ray Exposure on Menstrual Cycle and Fertility
The radiation exposure from X-rays? Hello Director Wang: I would like to ask you about the X-rays I had. Since February, I have had two knee X-rays, one chest X-ray after surgery in March, and after experiencing recurrent lower back pain in April, I had another X-ray at the rehab...
Dr. Ye Weicheng Reply:
Although you received five X-ray exposures over the past three months, the radiation dose from diagnostic X-rays is extremely low. Therefore, the health effects from radiation exposure are probabilistic in nature, and the probability is very low. This will not affect your menstru...[Read More] Impact of Frequent X-Ray Exposure on Menstrual Cycle and Fertility
Is It Safe to Have a Chest X-Ray When Preparing for Pregnancy?
Is it appropriate to undergo a general X-ray during the preparation for pregnancy? Hello Dr. Sun, due to work requirements, the company hopes that employees undergo a general X-ray examination once a year, primarily focusing on the "chest." However, since I am already 3...
Dr. Sun Shengyi Reply:
The period of greatest risk for radiation exposure from X-rays is during the first three months of pregnancy. If it is confirmed that a person is not pregnant, undergoing an X-ray poses no risk. It is advisable to avoid X-rays if there is a possibility of pregnancy or if one is a...[Read More] Is It Safe to Have a Chest X-Ray When Preparing for Pregnancy?
Techniques for Rib Examination: Diagnosing Rib Stability Issues
Techniques for Rib Examination Hello, Dr. Sun. I would like to ask you, if I have previously experienced external force that straightened my spine on both sides, what kind of examinations can I undergo to determine whether my ribs on both sides are resting on the vertebral bodies...
Dr. Sun Shengyi Reply:
General X-ray examinations related to the skeletal system are performed at specific angles for different body parts. Due to overlapping factors, it can be challenging to detect subtle, non-fixed changes between the thoracic vertebrae and ribs. If there is a possibility of unstabl...[Read More] Techniques for Rib Examination: Diagnosing Rib Stability Issues
Assessing Risks of Internal Exposure to Cs137 from Fukushima Radiation
Radiation dust from the Fukushima nuclear power plant? In light of the fact that the Atomic Energy Commission has assessed the risks of external ionizing radiation to the human body but has not addressed the risks of internal low-dose long-term radiation, and considering that the...
Dr. Sun Shengyi Reply:
Residents who have been in the Fukushima nuclear disaster area may be contaminated with cesium-137, and detection can only be confirmed using radiation detection instruments. If there has been close contact with others who are contaminated, the potential radiation exposure will d...[Read More] Assessing Risks of Internal Exposure to Cs137 from Fukushima Radiation
Smoking vs. Chest CT: Understanding Radiation Exposure and Cancer Risk
Smoking and Radiation Exposure from Chest CT Scans Hello, doctor: I came across an article stating that smoking 30 cigarettes a day accumulates approximately 16 millisieverts (mSv) of radiation exposure in a year. In comparison, a single chest CT scan exposes a person to about 7 ...
Dr. Yang Jinghua Reply:
Dear Mr. A-Bao: Due to the presence of trace amounts of components in cigarettes that can produce ionizing radiation, inhalation can lead to persistent effects on the lungs. The ionizing radiation from chest computed tomography (CT) scans is applied only during the examination ...[Read More] Smoking vs. Chest CT: Understanding Radiation Exposure and Cancer Risk
Understanding the Process and Radiation Dose of Chest CT Scans
The process of a chest CT scan? Hello Dr. Yang: During a chest CT scan, the radiologic technologist usually asks the patient to inhale and exhale. I would like to ask you: 1. How many times does a typical chest CT scan require inhalation and exhalation? Does one inhalation and ex...
Dr. Yang Jinghua Reply:
Dear A-Wen: The so-called dose for a single chest computed tomography (CT) scan is approximately 7 millisieverts, which is an average reference value; the actual dose should be based on the specific examination. For precise evaluation, a positioning assessment will be conducted p...[Read More] Understanding the Process and Radiation Dose of Chest CT Scans
Can CT Scans Detect Ulnar Nerve Damage?
Computed Tomography (CT) scan Can a computed tomography (CT) scan be performed for ulnar nerve damage? Can the damaged area be visualized?
Dr. Yang Jinghua Reply:
It is difficult to directly observe the ulnar nerve in Mr. OQ6078 through computed tomography (CT) imaging. Instead, we often rely on the surrounding skeletal structures, muscles, and blood vessels to assess for any signs of compression. To detect abnormal structural changes in t...[Read More] Can CT Scans Detect Ulnar Nerve Damage?
Impact of Abdominal CT on Sperm Quality and Pregnancy Safety
The impact of abdominal CT on sperm? Hello Director Yang, I had a follow-up examination for testicular cancer that included a CT scan of my abdomen and pelvis. Unfortunately, on the same day and the following day after the scan, my wife and I conceived. I am concerned whether the...
Dr. Yang Jinghua Reply:
Mr. Hao: Congratulations on the upcoming addition of a new life to your family. There is no clear evidence that a single computed tomography (CT) scan radiation dose causes significant sperm mutations. The principle of medical ionizing radiation exposure is to use it judiciously;...[Read More] Impact of Abdominal CT on Sperm Quality and Pregnancy Safety
Understanding the Role of Chest X-Rays Before Surgery
Preoperative examinations before hospitalization for surgery? Hello, doctor. I would like to ask about the purpose of taking a chest X-ray before surgery, along with blood tests and an electrocardiogram. Is the X-ray used to check for lung tumors as well?
Dr. Sun Shengyi Reply:
Preoperative blood tests, electrocardiograms, and chest X-rays are standard preparatory examinations before surgery. The chest X-ray is performed to ensure that there are no pulmonary abnormalities that could affect the surgery; it is not solely for the purpose of detecting lung ...[Read More] Understanding the Role of Chest X-Rays Before Surgery
Radiology FAQ
| Contrast Agent | Ct Scan |
| Ct Scan Radiation | Magnetic Resonance Imaging |
| Mri | Mri Report |
| Radiation | Radiological Examination |
| X-Ray | X-Ray Examination |
| X-Ray Radiation |