As the development of modern technology, advanced medical equipment continue to come out, which is known as a B-type ultrasonic imaging device (B ultrasound scanner), computed tomography (CT), magnetic resonance imaging (MRI). But if you check that the more price the better, it is a misconception, in fact, their functions have own strengths.
Resolution of CT is higher than B ultrasound scanner’s for diagnosing tumor. For small tumors in 1 to 2 cm, CT shows rate of 88%, but B ultrasound scanner over only 48%. For diagnosing cerebral hemorrhage, hydrocephalus, cerebral artery abnormalities and brain tumor, CT is good. CT has high values with diagnosing diseases of the central nervous system and head and neck disease.
In the diagnosis of gallbladder disease, accuracy of b ultrasound surpass CT, the rate of accuracy is generally at 95%. The awareness rate of b ultrasound is also high for liver cirrhosis, fatty liver, splenomegaly, intestinal disease. Ultrasound is low cost, and is no radiation on the body, patients can be given priority for special, such as pregnancy.
MRI can avoid the impact on the human body, such as CT, but also shows the lesion. At present it is more ideal to diagnose the bones, joints, spinal cord, pelvic organs, uterus, mediastinal disease, vascular disease and identification of cardiac infarction and other testing, but the cost is expensive. MRI has no injury of ionizing radiation to the human body, and can obtain the native three-dimensional imaging and multi-dimensional images without the need to rebuild. MRI clearly show structures of soft tissue, and is better than CT for the test of the central nervous system, bladder, rectum, uterus, vagina, joints and muscles, etc.
The advanced medical testing technology above talking about has their own strengths, which should be selected according to the disease for accurate diagnosis.

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