Exercises: 16

1. Radiology is the medical specialty concerned with the study of x-rays.

2. X-rays are invisible waves of energy that are produced by an energy source and

are useful in the diagnosis and treatment of disease.

3. Nuclear medicine is the medical specialty that studies the characteristics and

uses of radioactive substances.

4. Radioactive substances are materials that emit high-speed particles and

energy-containing rays from the interior of their matter.

5. Radioactivity is of three types: alpha particles, beta particles and gamma

rays.

6. Gamma rays are used effectively as a diagnostic label to trace the path and

uptake of chemical substances in the body.

7. Radiologist is a physician who specializes in the practice of diagnostic radiology.

8. A nuclear medicine physician specializes in diagnostic nuclear medicine

procedures.

9. A substance is said to be radiolucent if it permits passage of most of the x-rays.

10. Radiopaque substances are those that absorb most of the x-rays they are

exposed to.

11. Workers exposed to x-rays must wear a film badge.

12. X-rays travel in a straight line

13. Ionization is a chemical process in which the energy of a x-ray beam causes

rearrangement and disruption within a substance

14. Machines called CT scanners beam x-rays at multiple angles through a section

of the patient’s body.

15. Contrast medium is injected into the structure or fluid to be visualized so that a

specific part, organ, can be visualized as a negative imprint on the dense contrast

agent.

16. X-ray image of blood vessels and heart chambers is obtained after contrast is

injected through a catheter into the appropriate blood vessel or heart chamber is

called angiography

17. Contrast or air or both are injected into a joint, and x-ray images of the joint are

obtained is called Arthrography.

18. X-ray imaging after injection of contrast into bile ducts is called

Cholangiography.

19. X-ray image of contrast-injected blood vessels is produced by taking two x-ray

pictures (the first without contrast) and using a computer to subtract obscuring

shadows from the second image is called digital subtraction angiography.

20. X-ray record of the endometrial cavity and fallopian tubes is obtained after

injection of contrast material through the vagina and into the endocervical canal

is called Hysterosalpingography.

21. X-ray imaging of the spinal cord after injection of contrast agent into the

subarachnoid space is called Myelography.

22. X-ray imaging of the renal pelvis and urinary tract is called Pyelography.

23. Rays of light energy emitted as a result of exposure to and absorption of

radiation from x-rays is fluorescence.

24. Ultrasonography uses high-frequency, inaudible sound waves that bounce off

body tissues and are then recorded to give information about the anatomy of an

organ.

25. An instrument called transducer is placed near or on the skin, which is covered

with a thin coating of gel to ensure good transmission of sound waves.

26. The record produced by ultrasound is called a sonogram.

27. Cardiologists use ultrasound imaging to detect heart valve and blood vessel

disorders called echocardiography.

28. Doppler ultrasound and color-flow imaging make it possible to record blood

flow velocity and to image major blood vessels in patients at risk for stroke.

29. Magnetic resonance imaging uses electromagnetic energy rather than x-rays.

30. The contrast agent most commonly uses in MRI is Gadolinium

31. In Posteroanterior view x-ray travel from a posteriorly placed source to an

anteriorly placed detector.

32. In Anteroposterior view x-ray travel from an anteriorly placed source to a

posteriorly placed detector.

33. In a left lateral view, x-rays travel from a source located to the right of the

patient to a detector placed to the left of the patient.

34. In oblique view x-ray travel in a slanting direction at an angle from the

perpendicular plane.

35. The emission of energy in the form of particles or rays coming from the interior of

a substance is called radioactivity.

36. Half-life is the time required for a radioactive substance to lose half of its

radioactivity by disintegration.

37. Radioimmunoassay is an in vitro procedure that combines the use of

radioactive chemicals and antibodies to detect hormones and drugs in a patient’s

blood.

38. Nuclear medicine physicians use two types of tests in the diagnosis of disease in

vitro and in vivo

39. The combination of the radionuclide and a drug or chemical is called a

radiopharmaceutical.

40. Uptake refers to the rate of absorption of the radiopharmaceutical into an organ

or tissue.

41. A sensitive, external detection instrument called a gamma camera is used to

determine the distribution and localization of the radiopharmaceutical in various

organs.

42. Radioisotope is a radioactive form of an element substance.