[Fat Bear Science] Should I take an X-ray, CT scan or MRI? Don’t panic, experts say different conditions require different treatments......

Imaging tests are performed to better assess physical health, discover the root cause of disease, and eliminate risk factors.

When people go to the hospital because they feel uncomfortable, doctors often prescribe relevant imaging tests according to the location of the problem. So, it is very good to know more about how to choose imaging tests.

Zhang Jiuquan, Doctor of Medicine, Associate Professor, Associate Chief Physician, Master Supervisor, Director of the Department of Imaging, Affiliated Tumor Hospital of Chongqing University. High-end young and middle-aged medical talent in Chongqing, Vice Chairman of the Chongqing Integrated Traditional Chinese and Western Medicine Medical Imaging Group, Member of the Sixth Committee of the Chongqing Medical Association Radiology Professional Committee, Deputy Group Leader of the Sixth Committee of the Chongqing Medical Association Radiology Professional Committee, and Member of the Fourth Tumor Imaging Professional Committee of the Chinese Anti-Cancer Association. He is good at imaging diagnosis of the nervous system. He has presided over or participated in more than ten national and provincial and ministerial projects, and won a second prize of Chongqing Science and Technology Progress Award.

Lin Meng, chief technician, deputy director of the Department of Imaging, Affiliated Tumor Hospital of Chongqing University. Expert in new technologies of CT and MRI. Member of the Breast Group of the Imaging Technology Branch of the Chinese Medical Association, member of the Medical Imaging Professional Technology Committee of the Chongqing Medical Association, member of the Expert Database of the Chongqing Medical Imaging Quality Control Center, with rich experience in imaging technology.

Fracture: DR (digital X-ray) is the first choice, which is low-cost, convenient and time-saving; CT and three-dimensional imaging are selected for further examination and guidance of surgery. Magnetic resonance imaging can be used to assist in occult fractures.

Reexamination after fracture: DR is the first choice, which is most suitable for observing the healing of fractures and whether there is callus growth. CT examination can be used when necessary.

Joints: DR is the first choice for bone degeneration (aging) of joints and spine, and CT can also be chosen. However, DR is relatively cheap, while CT can also show some changes in soft tissues. MR (magnetic resonance imaging) is the first choice for arthritis, joint muscle ligament injuries and diseases involving neuromuscular diseases. Of course, ultrasound examination can also be chosen. Ultrasound examination is relatively convenient and inexpensive.

Bone tumors: CT examination is the first choice, and MR examination can also be selected according to the condition of the disease. Of course, if there is no CT or MR equipment, DR radiography can also reveal many problems.

Central nervous system: refers to the brain, brainstem and spinal cord. Generally speaking, diseases involving the central nervous system are more suitable for MRI examination, but it does not mean that other imaging equipment cannot be used for central nervous system examination.

Cerebrovascular: MR vascular imaging or CT angiography can be selected. If treatment is required at the same time, DSA (digital subtraction angiography X-ray examination) can be selected.

Cerebral hemorrhage: choose CT or MR.

Cerebral infarction: MRI is the first choice for early cerebral infarction. Both MRI and CT can be used for non-early cerebral infarction or old cerebral infarction.

Encephalitis and meningitis: MRI and CT.

Brain tumors: CT and MR enhanced scans.

Spinal cord lesions or spinal lesions affecting the spinal cord: MRI is the first choice, and sometimes CT examination is also helpful in confirming the disease.

Lungs and trachea: Generally speaking, DR and CT are better choices for lung examinations, while MR is weak in this regard.

Since CT is more expensive and radiates more radiation than DR, DR is the choice if you only suspect lung inflammation or are undergoing a physical examination for someone under 40 years old.

If you need to rule out early lung tumors or find abnormalities that require further diagnosis, CT can be chosen; if pleural effusion is suspected or needs to be aspirated, ultrasound has greater advantages.

Esophagus: The preferred examination for esophageal lesions is X-ray barium swallow examination. CT can also be used to observe esophageal lesions, but it is generally not the first choice. If further examination is needed, esophagoscopy can also be used.

Stomach and small intestine: Currently, when examining stomach diseases, clinicians prefer gastroscopy. However, before gastroscopy was used clinically, X-ray barium meal gastroenteroscopy was the mainstay of gastrointestinal examination. In addition, CT can now also be used to examine the stomach, but the examination method and procedure are a little more complicated.

Colon: Colon examination is similar to gastrointestinal examination. The first choice of clinicians is usually colonoscopy, but X-ray barium enema was also the only choice for colon examination. In addition, CT can also be used for colon examination. The difference between CT and colonoscopy is that CT can also observe the condition of the surrounding organs outside the intestinal cavity.

Liver, gallbladder, pancreas and spleen: There are many optional examination methods for these parts. Ultrasound examination is the first choice for routine examination or general physical examination; of course, CT and MR also have strong application indications in these parts, and can distinguish and diagnose solid tumors and hemangiomas that ultrasound cannot sometimes identify, but compared with CT and MR examinations, they are more time-consuming and expensive, and CT also has radiation damage; X-ray photography has no advantage in the examination of abdominal soft tissue organs.

Kidneys, ureters, and bladder: Ultrasound is the preferred method for examination of these areas, but some other imaging examinations are also very targeted. For example, positive stones in the urinary system can be easily detected on plain X-ray films, so DR radiography is the preferred method.

To observe the overall picture of the urinary system, its secretion and excretion functions, and space-occupying lesions, X-ray intravenous urography is the first choice. If the relationship between the space-occupying lesions and surrounding organs needs to be further clarified, enhanced examinations of CT or MR can also be selected. Of course, CT or MR can also be selected directly. This requires comprehensive consideration based on the condition of the disease and other factors.

Heart: Ultrasound is the first choice for cardiac function examination. Electrocardiogram can also be selected for general cardiac function examination. Other examinations such as isotope radionuclide examination, MR cardiac function imaging and CT cardiac function imaging can also achieve a certain degree of cardiac function disease (such as soft plaque calcification). CT angiography (CTA) is the first choice for exclusion of examinations. If coronary angiography is combined with treatment, digital subtraction angiography (DSA) is selected.

Aorta: CT angiography is the first choice. MR angiography can also be selected if there are no contraindications to MR.

Carotid artery: Vascular ultrasound is the first choice. If the nature of vascular wall plaques needs to be determined, carotid artery CTA can be selected. If combined treatment is required, DSA can be selected. If there are no contraindications to MR, CE-MRA of carotid artery magnetic resonance imaging can also be selected.

Venous thrombosis: Vascular ultrasound is the preferred method for the peripheral venous system, while CT venography is the preferred method for the vena cava and venous system.

There are three main methods for breast imaging examinations. Depending on the different situations, you can choose breast ultrasound, X-ray mammography or MR dynamic enhancement examination.

In comparison, breast ultrasound is simple, easy to perform and inexpensive, but it is insensitive to microcalcifications, an important feature of breast cancer.

The main disadvantages of X-ray mammography are that it produces a small amount of radiation, that the compression of the breast during the examination may be difficult for some people to bear, and that lesions close to the chest wall may be missed for many reasons.

The main disadvantages of MR are not only the difficulty in identifying tiny calcifications, but also other factors that need to be considered, such as high price, long examination time, and unbearable noise.

Text/Fat Bear Photos/Internet (please contact for deletion) Review/Zhang Jiuquan Lin Meng

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