CT Scan

Computed tomography (CT) is a computer-aided x-ray technique. X-rays consist of electromagnetic waves of energy. They penetrate the body to varying extents depending upon the density of the structures being viewed. The result is black and white images of interior portions of the body. A CT scan produces detailed cross-sectional views of the body, similar to slices of bread.
The technology behind CT scans has advanced rapidly in recent years. Older machinery used to take minutes to obtain enough information for a single "slice." Now, the same image can be produced in seconds. Newer scanners called spiral or helical scanners are so fast that they can scan the entire chest during one held breath. These devices can also produce three-dimensional scans.

Who is a candidate for the test?

CT scans are performed to evaluate:

abnormalities that showed up on other other types of x-rays.

injuries.

tumors related to cancer. CT scans can indicate the progress of some cancers if the cancers spread or metastasize and the effectivness of treatment.

bony abnormalities.

brain abnormalities.

abdominal symptoms. Use of CT scans in these cases can often prevent exploratory surgery.

suspicious chest abnormalities.

CT scans are also used to guide needles when taking tissue samples. In addition, the technique is useful in gauging a person's recovery after an operation. CT scans can also be used to guide instruments for surgery deep in the brain.

How is the test performed?

A person having a CT scan will need to undress and put on an exam gown. Next, the person will lie on a narrow table. The table will slide through a machine that looks like a doughnut. This is called the gantry. While in the gantry, an x-ray tube travels around the individual creating computer-generated x-ray images.
Some types of exams require the individual to receive an intravenous injection of iodinated contrast, which is a dye that makes some tissues show up better. Scans of the intestines sometimes call for the person to drink diluted iodinated contrast solution prior to the exam. After the exam, the technologist will view the pictures. If they are adequate, the person is free to leave.

ECG

An electrocardiogram, also called an ECG or EKG, is a graphic record of the heart's electrical activity. Healthcare providers use it to help diagnose heart disease. They can also use it to monitor how well different heart medications are working.

Who is a candidate for the test?

An ECG is done on a person to help diagnose heart disease. It may also be used to monitor how well different heart medications are working. Persons coming into the emergency room with chest pain, shortness of breath will have an ECG performed. An ECG may be necessary prior to a person having major surgery as a baseline tracing.

How is the test performed?

A person can have an ECG while either lying down or exercising on a treadmill. A technician will use an adhesive to attach from 12 to approximately 15 electrodes at specific sites on the skin. These sites are selected on both arms and on the chest. The sites will be cleaned and perhaps shaved before the electrodes are attached. A machine then records the electrical activity of the heart under conditions a doctor has specified. An ECG usually takes about 5 minutes to perform.

Hemoglobin

Hemoglobin is a protein in red blood cells. It carries oxygen from the lungs to cells throughout the body, and carries carbon dioxide from the cells to the lungs. A hemoglobin test measures the level of this protein in a sample of blood.

Who is a candidate for the test?

Often, this test is done as part of a complete blood count, or CBC. Or it may be done:

during pregnancy

during infancy

when a person has symptoms of anemia, such as lack of energy, pale skin, and shortness of breath

when a person is being treated for anemia

when family history or ethnic or racial background puts a person at risk for a blood disorder. Examples include hemoglobin disorders, sickle cell disease, and thalassemia.

How is the test performed?

Blood for the test is usually taken from a person's forearm. First, a tight band is put on the upper arm to make the veins swell below it. An area of skin on the forearm over the vein chosen is cleansed. Then a needle is inserted into the vein and a sample of blood is collected in a tube.
Occasionally blood is taken from another site, such as a finger or heel. If so, the skin is cleansed and pricked with a sharp tool called a lancet. Drops of blood are collected in a tiny tube. The blood is analyzed at a lab.

Biopsy -- Detailed

A biopsy is the removal of a sample of tissue from the body. The sample is then examined under a microscope. Biopsies are used to diagnose many medical conditions, from skin problems to cancer.

Who is a candidate for the test?

Anyone whose medical condition needs a specific diagnosis may need a biopsy. A biopsy may also be needed to monitor a disease or condition.

How is the test performed?

There are several different kinds of biopsy.
In an excisional biopsy, a whole organ or whole lump is removed by surgery. This may require general anesthesia. General anesthesia means that a person is put to sleep with medications and feels no pain. This kind of biopsy is often used to diagnose cancer.
For an incisional biopsy, the surgeon cuts out a small piece of the tissue or lump. This may require general or local anesthesia. Local anesthesia means that medicine is injected locally in an area to numb it, but the person stays awake. This kind of biopsy is used to diagnose some cancers. It is also used to tell the difference between normal and diseased tissue.
A punch biopsy takes a small piece of skin using a sharp punch tool. The punch only cuts through the top layers of skin. The skin is cleaned and numbed first with local anesthesia or topical anesthesia. A punch biopsy is used to diagnose skin conditions.
In a needle biopsy, a needle is inserted through the skin into the tissue. Tiny amounts of tissue are then sucked out through the needle. This is usually done under local anesthesia. This kind of biopsy is used to diagnose liver problems, thyroid disease, and breast cancer. It is also used for other conditions, especially tumors in organs that are hard to reach.
In a bone marrow biopsy , a needle is inserted into a bone, usually the hip bone, or pelvis. Bone marrow cells are sucked out of the inside of the bone. This sometimes causes moderate pain. This kind of biopsy is usually done under local anesthesia. It is used to diagnose leukemia, other cancers, and low blood counts in some situations.
An endoscopic biopsy uses an endoscope, a lighted, flexible tube, to get the tissue. The endoscope can be inserted through the skin with local anesthesia. It can also be inserted into the bowel from the top or bottom. An endoscope can be inserted into the lungs, bladder, or uterus, as well. The endoscope is used to find the abnormal tissue. Then, a tiny tool can be placed through the endoscope. The tool can take a small piece of the abnormal tissue. Endoscopic biopsy can be used to diagnose many different diseases and conditions.
A colposcopy-directed biopsy uses a colposcope, which is a special microscope for examining the cervix. The cervix is the lower part of the uterus that connects to the vagina. This kind of biopsy usually requires no anesthesia. It is used to collect abnormal tissue from the cervix. It is usually done after a woman has an abnormal Pap smear.
In a stereotactic biopsy, special X-ray tests are used to guide the doctor. This allows the doctor to insert a biopsy needle into the abnormal area. It is used when the abnormal tissue cannot be seen or felt directly, and helps make sure that abnormal tissue is taken. It is often used when abnormalities are found on X-ray tests, such as mammography or a CT scan.