The frequency of ultrasound used for medical diagnosis is about
A. 2-20Hz
B. 2-20KHz
C. 2-20MHz
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In an early pregnancy of approximately 6 weeks, fetal age can be estimated by measuring
A. a) From nose to tail.
B. b) From crown to rump.
C. c) Width of head.
In an inversion recovery T1-weighted image, tissues with short, medium, and long T1 relaxation times will have low T1 contrast between each other when TI is:
A. ) short, around 10 milliseconds.
B. ) long, around 3 seconds.
C. ) both A and B.
The diagnosis of lung tumours with CT imaging methods is routinely used due to:
A. a) the small difference in density between the lungs and the tumours
B. b) the large contrast between low density, air-filled lung tissue and solid lung tumour masses
C. c) the absence of other imaging modalities to diagnose tumours
Which contrast agent is used routinely during a Coronary CT angiogram?
A. Gadolinium
Barium Sulfate
C. Iodine