Part 2: Basic Diagnostic Health Tests

These basic health tests can help your doctor with your diagnosis and treatment. Know what they are so you know that you are getting it when it is needed. These can be baseline, and routine screening tests as well.


The ultrasound is also referred to as a sonogram or sound wave test. It uses sound waves to make images of body parts. This changes electrical energy to sound waves that go through the skin into your body. When the waves contact the body’s organs, they reflect to the transducer, producing echoes. The echoes are then converted into still or moving images by a computer that makes a picture of your organs. The technician is able to see this on the monitoring screen and to make an X-ray or Polaroid-type picture. The ultrasound uses no radiation.  In this test the technician applies gel to the area to be tested. A transducer held by the technician is moved back and forth against that part of the body. This sends out the sound waves that go back into the computer.



The sonogram is commonly used to look at your internal organs in the abdomen (such as the gallbladder, kidneys, liver, spleen, and pancreas), prostate, uterus, and ovaries. It is also used to look at blood vessels (arteries and veins), the thyroid gland, breasts, and the skull. In a pregnant patient, actual moving images of the fetus can be seen. As there is no radiation exposure, the sonogram is very valuable in following fetal development in pregnancy. It is also able to detect and diagnose other conditions related to pregnancy. Sonograms are also useful in checking the heart. These are called echocardiograms or Doppler echos.
Computerized axial tomography, CT or CAT scan is another way to make images of body parts. The CT scanner uses X-ray beams that rotate around the body. These beams then go through a detector, and a computer analyzes and processes the data into an X-ray film. The CT machine has a table that is pulled in and out of the machine, which is a large hollow tube (like a doughnut) that can surround the body. During the test the patient lies down on the table. The scanner (inside the hollow tube) then rotates around the patient.  The CT scan is able to image many parts of the body. It detects more than a regular X-ray and produces two-dimensional views. This test is commonly used to pick up tumors, infections, enlarged organs, and many other abnormalities.


The MRI (magnetic resonance imaging) scan is another diagnostic test that does not use X-rays. Instead, it uses magnetized energy. The images produced are extremely detailed pictures of the body part scanned. It is very much like looking at the pictures in an anatomy book or almost like looking at a person internally. The MRI machine is designed much like a CT scan machine, except a magnet is in the hollow tube instead of X-ray beams. The test is also done while the patient lies down on a table that moves in and out of the machine. The MRI scan takes about thirty minutes to an hour. The MRI is not recommended for persons with metal or electronic implants (such as pacemakers, joint pins, prosthetics, artificial heart valves, metal fragments, shrapnel, IUDs, etc.), as those might interfere with the machine. Be sure your doctor and technician are made aware if you have any such implants. For the claustrophobic person, the closed space of the MRI machine may create some anxiety.  Again, alert your doctor and technician. A mild sedative may be necessary prior to the test to help relax you, or you may be sent to a facility that has an open MRI. MRI scans are useful for scanning almost any body part for almost anything. Tumors, cysts, aneurysms, herniated back discs, and orthopedic conditions are among the many abnormalities that can be detected with this test.

The mammogram is a plain X-ray picture of the breast. It requires a special machine that compresses each breast against X-ray film to take the picture. The X-ray passes through the breast tissue and shows how the breast looks inside.  This test is excellent for detecting tumors and cysts. It may also show if the area is benign (no cancer) or malignant (cancer). The mammogram is able to pick up cancers that are too small to be felt or seen. It is a valuable cancer screening test.


Medical diagnostic tests are screening as well as diagnostic tools.  Along with a thorough history and physical, these tests can help make a correct diagnosis. Best health!