All about Tests
Throughout your diagnosis and treatment, you will have tons of different tests. Some will be more routine than others and you’ll get used to them. Others will just be annoying because you don’t want to be bothered. Unfortunately, some may be uncomfortable or painful. Here are the most common tests you will have:
- Lumbar Puncture or Spinal Tap
- Bone Marrow Aspirate and Biopsy
- CAT (CT) Scan
- Blood tests
- Nuclear Scan: Bone, Gallium
- Red Blood Cells
- White Blood Cells
- Echocardiogram (ECHO)
- Absolute Neutrophil Count
- Electrocardiogram (ECK or EKG)
- Summary Chart
- Pulmonary Function Test
- Blood Cultures
- Vital Signs
The subspecialty of medicine called Radiology was developed from the discovery of the x-ray by Wilhelm Conrad Roentgen in 1895. X-rays are a form of electromagnetic radiation that have high energy and short wavelength and are able to pass through various substances including body tissue. When X-rays are passed through parts of your body, an image is created. Denser tissue, such as bones, blocks more of the rays than less dense tissues, such as the lung and are recorded using special photographic film. When you have an x-ray you have to remove all metal objects. The part of your body to be scanned is placed between the x-ray machine (that produces the rays) and a special screen used to obtain the image. You have to stay as still as possible for a few seconds. It is completely painless and there are no side effects. The radiologist will look at the images and prepare a report with the results.
MRI – Magnetic Resonance Imaging
Magnetic Resonance Imaging (MRI) is a non-invasive procedure using magnetism and radio waves to provide detailed images of your body and its soft tissue structures. MRI’s help diagnose your disease, monitor the progress of your treatment or help understand other medical situations that arise. In most cases, there is no special preparation for an MRI scan. You can eat and drink normally on the day of the scan although it is best to avoid large amounts of coffee or other things that might make you restless. See a panoramic video of an MRI. Note: This will require QuickTime Player (a free download). Depending on what part of your body is being scanned, you might have to wear a gown, but usually you can wear regular clothes (without heavy metal attachments). Because of the strong magnetism, it is very important not to bring any metal into the scan room. You will be asked to remove your watch, keys, coins, earrings and anything else metallic. For the actual procedure, you lie on your back on a movable scanning table that moves into the MRI scanner. Depending on what type of scan is necessary, the table moves you into the machine head or feet first. Once the body part to be scanned is in the exact center of the magnetic field, the scan begins.
Most kids have no trouble during the procedure but some feel claustrophobic. To make you more comfortable, the inside of the scanner is well lit, and has a fan that gently blows fresh air. Even though the technician is in another room during the procedure, he or she can see you at all times and you can see through a mirror positioned at eye level inside the machine. You can also talk to the technician through an intercom system. If you want, you can usually bring someone with you in the room (check with the technician first). Most MRI scans take between 30 and 90 minutes. Your only job is to remain completely still because even slight movement can spoil the images. During the scan you will hear a variety of sounds such as humming and hammering. It may sound like the technician is hitting the side of the scanner with a large hammer. These sounds are normal. You may be given earplugs or stereo headphones to muffle the noise (in most MRI centers you can even bring your own cassette or CD). But don’t be surprised if the music is drowned out by the noise. Other than maybe being a little uncomfortable (and loud!), an MRI is completely painless and you should have no side effects to worry about.
CAT (or CT) Scan
CAT scanCAT stands for Computerized Axial Tomography. (sometimes referred to as CT scans). CAT Scans combine x-rays and computers to produce very detailed cross sectional images of your body. See a panoramic video of a CAT Scan. Note: This will require QuickTime Player (a free download). Depending on what part of your body is to be scanned, you may be given something called “contrast” to make things show up better on the scan. The contrast is given through an IV or if you are having an abdominal scan, you may have to drink it. It tastes really terrible but it’s important. Just make sure it’s cold and that you have a good “chaser” nearby – soda or juice. The good thing about CT’s is that they are quick but you need to lie very still to get a good scan. After the scan is done, it can be computer reconstructed to show three-dimensional images of the part of your body that was scanned. Because the machine produces X-rays, the technician is in a separate room near the computer but can talk with you through an intercom. You will probably be alone in the room, unless you request that someone be with you. That person will need to wear a lead vest as protection against the x-rays. If you are interested in the physics of CT scans, check this out.. Pretty interesting!
Nuclear Scan: Bone, Gallium
Nuclear Scans provide images of your internal organs and bones not possible with conventional x-rays. Instead of being bombarded with X-rays, a low level radioactive compound is injected, swallowed, or inhaled into your body. The amount of radiation received from the radioisotope is very low – about the same as from a dental x-ray. So don’t worry – you won’t glow. After your body has had time to absorb the radioactive material, a special imaging camera, that looks like an x-ray machine, is passed over the part of your body to be examined. Bone scans and Gallium scans are the most common nuclear scans for kids with cancer. They are usually used together with other tests to make a definite diagnosis.
Bone scans can show abnormalities long before they show up in x-rays, which is why your doctor probably ordered one. The radioactive compound is given through an IV and is absorbed by your bones as it travels through your body. You have to drink a lot of water or juice right after the isotope is injected to clear your body of radioactive material not absorbed by your bones. The bone scan may take about an hour and you have to lie very still while the camera moves back and forth. You might be asked to change positions several times to get different images. Because no x-rays are emitted, you can have someone stay in the treatment room with you. The radioactive material or tracer concentrates in areas where there is a lot of activity, so to speak – like normal growing bone or in bone tumors or bone infections. These areas will show up as “hot spots” on the scan.
A gallium scan is a whole body nuclear scan that helps detect tumors and inflammations. Gallium citrate is the radioactive compound that is injected through an IV. It accumulates in areas where there is rapid cell growth, such as tumors and sites of infection, helping your doctors make an accurate diagnosis and providing appropriate follow-up. There is nothing special you have to do to prepare for the scan. The imaging is done 24-48 hours after the radioisotope is injected and takes 30-60 minutes, during which you have to lie still.
Ultrasound scans are images of your internal organs created by using sound waves. High frequency waves are directed at your body and then reflected (echoed) back to a scanner that creates an image of the area scanned. A special gel is spread on the skin over the area to be examined. This helps to define the area as clearly as possible by enhancing the transmission and reception of the sound waves. The ultrasound scanner or transducer looks like a small paint roller that the technician moves over the area to be scanned. It is completely painless but the gel can sometimes feel a bit cold. There is nothing special that you have to do to prepare for an ultrasound and there are no side effects.
An echocardiogram is an ultrasound test specifically for your heart. If your treatment plan includes anthracyclines, which are potentially damaging to your heart, you will probably have this test done periodically. Echocardiograms, like other ultrasounds, use reflected sound waves to create an image of your heart. A special gel is applied over the area to be examined and a scanner is then moved over the area. It is completely painless but the gel can sometimes feel a bit cold.
Electrocardiogram (ECG OR EKG)
Your heart generates electrical impulses causing it to beat or contract. The electrocardiogram (ECG or EKG) records your heart’s rhythms and electrical impulses through 10 electrodes that are placed on your chest, arms and legs. The test takes only 5-10 minutes to complete and is completely painless. It is usually done right in your hospital room or treatment room. If you are taking certain chemotherapy drugs called anthracyclines, you will probably have an EKG prior to treatment and then again, periodically throughout your treatment. Because anthracyclines can cause damage to your heart muscle, your doctor will closely monitor your heart’s function and adjust your treatment plan if necessary.
This test evaluates your hearing. If your treatment plan includes the drug cisplatinum, you will likely have a number of audiograms. A possible side effect of cisplatinum is hearing loss so you will probably have a baseline test done prior to starting the drug, and then periodically throughout your treatment. If you notice any change in your hearing, be sure to tell your medical team.
Pulmonary Function Test
A pulmonary function test measures how well your lungs function, specifically how much air your lungs can hold, and how effectively they work. It also looks at the forcefulness of your breathing. You may have a pulmonary function test because some chemotherapy drugs affect lung functioning.
Lumbar Puncture or Spinal Tap
A lumbar puncture or spinal tap may be used to diagnose as well as treat your cancer. The term lumbar refers to your lower back between the pelvis and the ribs. You might have several spinal taps throughout your treatment. During a spinal tap, a very small needle is inserted between two bones (vertebrae) of your spine. Using this needle, a small amount of spinal fluid is withdrawn to check for cancer in your central nervous system. A chemotherapy drug may also be injected through this needle to treat your cancer (referred to as intrathecal chemotherapy). Spinal taps take only about 20 minutes. Usually, you are asked to lie on your side and “curl up into a ball”, knees bent and pulled up as far as possible with your chin touching your chest. In this position, the bones or vertebrae in your spine separate, letting the needle pass between the vertebrae and into the spinal canal. A local anesthetic is used to numb the skin before the needle is inserted. Even with the local anesthetic, you might still feel some discomfort. Try to use relaxation techniques like deep breathing and visual imagery to stay calm. When the test is done, a piece of sterile tape is applied to your skin where the needle was inserted. Your medical team will tell you exactly what to do after the procedure, but you will usually be told to lie flat on your back for at least an hour to prevent a headache (caused by the temporary imbalance of your spinal fluid). Even with this precaution, you may still have a headache for several days that is worse when you sit or stand up. Sometimes drinking caffeine – cola or coffee – will help the headache subside.
Bone Marrow Aspirate and Biopsy
You will likely have many bone marrow biopsies throughout your treatment. This test is extremely important for accurately diagnosing some types of cancer as well as tracking the progress of your therapy. This procedure is usually performed by one of your doctors or nurse practitioners. The bone marrow is a soft tissue inside some of your larger bones. The bone marrow produces red and white blood cells and platelets. By examining a small amount of your bone marrow, usually taken from your hip bone in an area called the ileac crest, your doctors can make important decisions about your care. Guidelines about sedation or anesthesia differ from one hospital to another. You may receive medication to sedate you (put you to sleep). Some common drugs used are fentanyl and propofol and may be administered by an anesthesiologist. Ask your medical team about this. The procedure will probably be done in a treatment room where you lie face down on an examining table. A small blanket or towel may be placed under your hips to raise them. If you receive sedation medicine, you will begin to feel sleepy very soon and will not feel any of the procedure. Some kids really like the feeling from propofol. Very dreamy and relaxing. If you want, you can bring a walk-man or CD player to help you stay calm. After you are asleep (if you are sedated), the biopsy area is cleansed and a local anesthetic is injected to numb the skin. If you are not sedated, you will feel the prick of the needle and the local anesthetic will sting at first. Bone Marrow Procedure A biopsy needle is then inserted through your hip bone into your bone marrow. A small amount of bone marrow is pulled up into a syringe for testing. If you are not asleep, you may feel some pressure and pain as the needle is pushed into your bone. Once the bone marrow is extracted, a new needle will be placed in the same hole to get a small specimen of bone for further testing. The needle is pressed forward and rotated in both directions. This forces a tiny sample of bone into the needle. If a good sample is not gotten, the doctor or nurse doing the procedure may need to try again. The needle is then removed and a pressure bandage (to stop bleeding) is applied. A bone marrow technician will examine the bone marrow and prepare a report for your doctor. This usually takes a few days. Your back may be sore for a few days. Tylenol may help relieve the soreness. If you have multiple bone marrow biopsies throughout your treatment, your doctor or nurse will try to alternate sides to reduce scar tissue build up. After a while, you will begin to feel like a pin cushion but unfortunately it’s necessary.
Blood tests Blood tests will become part of your life with cancer, so it’s important that you understand what they’re for. Various types of blood tests help diagnose your cancer. Sometimes, they are the first indicators of disease. Blood tests are also used to track the progression of your disease as well as help make decisions about your treatment. Your doctor will often order a complete blood count (CBC). Your blood “counts” will be closely tracked throughout treatment. Three primary types of blood cells are formed in your bone marrow: red cells, white cells, and platelets. Plasma is the liquid part of your blood in which the other cells travel. Certain kinds of cancer will affect the normal production of these cells. Some of the treatments you will receive, especially chemotherapy, will also affect your body’s ability to produce blood cells. Here are some of the most important “counts” you will track:
Red Blood (RBC)
Your red cells are primarily responsible for carrying oxygen throughout your body.
Red cells contain hemoglobin, the molecule that carries oxygen and carbon dioxide in your blood throughout your body. If your hemoglobin is low, you will be anemic with symptoms like pale skin, shortness of breath, and fatigue. You may have low hemoglobin at diagnosis as well as during treatment because of your bone marrow’s inability to produce new red cells.
Hemocrit Test Hematocrit refers to the volume of red blood cells in your system. (This is also called packed cell volume – PCV). Your hematocrit count is the ratio of red cells to plasma (the liquid part of your blood). It is expressed as a percentage. As an example, if your hematocrit is 30 it means that 30% of the blood that was drawn is red cells; the remaining 70% is plasma. When you are on chemotherapy, your marrow’s ability to make new red cells is decreased, so your hematocrit will go down. Because there is less oxygen in your body, you will feel tired and have little energy. If your hematocrit drops below about 18 percent, you will probably need a red blood transfusion. Your medical team will tell you the best thing to do.
White blood cells
Your white blood cells are responsible for fighting infection. Because cancer treatment affects your body’s ability to produce white cells, your risk of infection becomes very high.
White Blood Cell Differential (DIFF)
The differential (or diff) refers to the distribution of different kinds of white cells in your blood. Each type of white cell will be listed as a percentage of the total. Neutrophils are the most important-infection fighting white cells. On your lab reports, the “differential” or “diff” will show the percentage of each type of white cell, all together equaling 100%. As an example: Segmented neutrophils (or segs) 49% Band neutrophils (or bands) 10% Basophils 1% Eosinophils 1% Lymphocytes 29% Monocytes 10%
Absolute neutrophil count (ANC)
This count is a measure of your body’s ability to fight infection. It is the percent of neutrophils (segs + bands) multiplied by the total white blood count (WBC). The magic number is an ANC of 1,000 or more. When your ANC is less than 1,000, you are at very high risk for infection. IMPORTANT: If you have a fever higher than 100.5 F or 38.5 C and your ANC is less 0 than 1,000, you will usually be admitted to the hospital to begin antibiotic treatment. Because the fever may be caused by a bacterial infection, extreme caution must be taken. Even if you feel perfectly fine, this precaution is necessary. Spending a few days in the hospital – just in case – is much better than taking a chance with a potentially life-taking infection. Here’s an easy way to calculate your ANC using actual results blood counts: WBC = 1,000 Segs = 49% Bands = 10% Add the segs and bands: 49 + 10 = 59 Multiply by total WBC: 59 x 1,000 = 59,000 Divide by 100: 59,000 / 100 = 590 ANC
Platelets are the cells in your blood necessary to stop bleeding. Because chemotherapy affects your bone marrow’s ability to produce platelets, you will probably need platelet transfusions during your treatment. Signs of low platelet count include: * Bruising with no apparent cause * Any unusual bleeding (nosebleeds, bleeding gums, vaginal or anal bleeding, prolonged bleeding from a cut) * Petechiae (small red or purple spots on the skin)
The following chart helps to summarize the important things to know about blood counts. Some labs use different measures to report results. Just be sure you are comparing apples to apples.
|Type of Blood Cell||Normal Range||Possible Signs of Low Counts||What to do when counts are low|
|Red: carries oxygen||Hematocrit: 35-45% Hemaglobin: 12-14g/ul||• Pale skin • Tired, no energy • Shortness of breath||• Have red blood transfusions • Get extra rest • Eat well|
|White: fights infections||4.8 – 10.8 mill/ul||• Fever • Cough • Infections • Redness around sores||• Report fever over 100.5 F and 38.0 C • Start antibiotics • Wash hands often and well • Avoid crowded public places • Don’t get any body piercings or tattoos • Take extra precaution if sexually active. Abstinence is best until your counts recover.|
|Platelets: stops bleeding||150 – 400 thousands/ul||• Bruising • Bleeding • Petechiae (small red spots)||• Have platelet transfusions • Avoid rough activity, like contact sports. • Don’t get any body piercings or tattoos • Take extra precaution if sexually active. Abstinence is best until your counts recover.|
If your ANC (Absolute Neutrophil Count) is less than 1,000 and you develop a fever of more than 100.5 F or 38.0 C, the risk of serious bacterial infection is high. You will probably be hospitalized and started on IV antibiotics. In order to know exactly what antibiotics best kill the bacteria, blood cultures might be drawn.
What this means is blood is drawn from your central line, and sent to the lab to see what type of bacteria grows in the culture medium (a substance that germs grow in). The most effective antibiotic to treat the specific bacteria can then be administered.
Get used to this! Your “vital signs” will be taken often (most annoying in the middle of the night!) These include:
Taking your temperature is important to detect possible infection. Most hospitals will record temps in Centigrade degrees. Your temperature can be taken in a number of ways:
Oral: In your mouth.
Auxiliary: In your armpit.
Rectal: In your butt. Not usually the area of choice.
Aural: In your ear.
If you don’t already have one, you should have a reliable thermometer at home. Remember that a fever over 100.5 F or 38.0 C requires a call to your doctor if you are neutropenic!
Blood Pressure Your blood pressure is a measure of the force of your blood against the walls of your arteries. Blood pressure is recorded as two numbers-the systolic pressure (as the heart beats) over the diastolic pressure (as the heart relaxes between beats).
The measurement is written one above the other, with the systolic number on top and the diastolic number on the bottom. Normal blood pressure is about 120/80. Many things affect your blood pressure including being nervous or scared, or stressed out. High or low blood pressure can be an indicator of a serious medical problem, so it is watched closely.
Your blood pressure might be taken manually with a blood pressure cuff and a stethoscope or electronically with a digital readout.
Your respiration rate is simply the rate at which you are breathing. If you notice the person taking your vital signs is staring at you funny while taking your temperature, he or she is probably watching you breath. They count how many times you breathe in and out over a period of time.
Usually while taking your temperature or blood pressure, the person taking your vital signs feels your wrist to check your pulse. The pulse represents the beating of your heart, specifically the ejection of blood from the left ventricle to the general circulation of the body.