Prepare for a Test

Preparing for a CT Scan

You should wear comfortable, loose-fitting clothing to your exam. You may be given a gown to wear during the procedure. Metal objects including jewelry, eyeglasses, dentures and hairpins may affect the CT images and should be left at home or removed prior to your exam. You may also be asked to remove hearing aids and removable dental work. You may be asked not to eat or drink anything for several hours beforehand, especially if a contrast material will be used in your exam.

You should inform your physician of all medications you are taking and if you have any allergies. If you have a known allergy to contrast material, or "dye," your doctor may prescribe medications to reduce the risk of an allergic reaction. Also inform your doctor of any recent illnesses or other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or thyroid problems. Any of these conditions may increase the risk of an unusual adverse effect. Women should always inform their physician and the CT technologist if there is any possibility that they are pregnant.

Click here for information about pregnancy & x-rays.

Preparing for a Lower GI Tract X-Ray Radiography (Barium Enema)

Your physician will give you detailed instructions on how to prepare for your lower GI imaging. You should inform your physician of any medications you are taking and if you have any allergies, especially to barium or iodinated contrast materials. Also inform your doctor about recent illnesses or other medical conditions.

On the day before the procedure, you will likely be asked not to eat and to drink only clear liquids like juice, tea, black coffee, cola or broth, and avoid dairy products. After midnight, you should not eat or drink anything. You may also be instructed to take a laxative (pill or liquid form) and to use an over-the-counter enema preparation the night before and possibly a few hours before the procedure. Just follow your doctor's instructions. You can take your usual prescribed oral medications with limited amounts of water.

You may be asked to remove some or all of your clothes and to wear a gown during the exam. You may also be asked to remove jewelry, removable dental appliances, eye glasses and any metal objects or clothing that might interfere with the x-ray images.

Women should always inform their physician and x-ray technologist if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to radiation. If an x-ray is necessary, precautions will be taken to minimize radiation exposure to the baby.

Infants and children may undergo lower GI radiography. Usually, there is no special preparation, but your doctor will give you detailed instructions to prepare your child for the examination. The use of barium and the taking of x-ray images is similar to that described for adults.

Preparing for a Mammogram

Before scheduling a mammogram, the American Cancer Society (ACS) and other specialty organizations recommend that you discuss any new findings or problems in your breasts with your doctor. In addition, inform your doctor of any prior surgeries, hormone use, and family or personal history of breast cancer.

Do not schedule your mammogram for the week before your period if your breasts are usually tender during this time. The best time for a mammogram is one week following your period. Always inform your doctor or x-ray technologist if there is any possibility that you are pregnant.

The ACS also recommends you:

  • Do not wear deodorant, talcum powder or lotion under your arms or on your breasts on the day of the exam. These can appear on the mammogram as calcium spots.
  • Describe any breast symptoms or problems to the technologist performing the exam.
  • Obtain prior mammograms and make them available to the radiologist at the time of the current exam.
  • Eat or drink as you normally would.
  • Take your medications as usual.
  • Arrive 30 minutes before your scheduled appointment.

Information on Mammography

Preparing for an MRI Exam

You may be asked to wear a gown during the exam or you may be allowed to wear your own clothing if it is loose-fitting and has no metal fasteners. Guidelines about eating and drinking before an MRI exam vary with the specific exam and also with the facility. Unless you are told otherwise, you may follow your regular daily routine and take food and medications as usual. Some MRI examinations may require the patient to receive an injection of contrast material into the bloodstream. The radiologist or technologist may ask if you have allergies of any kind, such as allergy to iodine or x-ray contrast material, drugs, food, the environment, or asthma. However, the contrast material most commonly used for an MRI exam, called gadolinium, does not contain iodine and is less likely to cause side effects or an allergic reaction.

The radiologist should also know if you have any serious health problems or if you have recently had surgery. Some conditions, such as severe kidney disease may prevent you from being given contrast material for an MRI. If there is a history of kidney disease, it may be necessary to perform a blood test to determine whether the kidneys are functioning adequately.

Women should always inform their physician or technologist if there is any possibility that they are pregnant. MRI has been used for scanning patients since the 1980s with no reports of any ill effects on pregnant women or their babies. However, because the baby will be in a strong magnetic field, pregnant women should not have this exam unless the potential benefit from the MRI exam is assumed to outweigh the potential risks. Pregnant women should not receive injections of contrast material.

If you have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your physician for a prescription for a mild sedative prior to the scheduled examination. Jewelry and other accessories should be left at home if possible, or removed prior to the MRI scan. Because they can interfere with the magnetic field of the MRI unit, metal and electronic objects are not allowed in the exam room. These items include:

  • Jewelry, watches, credit cards and hearing aids, all of which can be damaged.
  • Pins, hairpins, metal zippers and similar metallic items, which can distort MRI images.
  • Removable dental work.
  • Pens, pocketknives and eyeglasses.
  • Body piercings.

In most cases, an MRI exam is safe for patients with metal implants, except for a few types. People with the following implants cannot be scanned and should not enter the MRI scanning area unless explicitly instructed to do so by a radiologist or technologist who is aware of the presence of any of the following:

  • Internal (implanted) defibrillator or pacemaker
  • Cochlear (ear) implant
  • Some types of clips used on brain aneurysms
  • Some types of metal coils placed within blood vessels

You should tell the technologist if you have medical or electronic devices in your body, because they may interfere with the exam or pose a risk, depending on their nature and strength of the MRI magnet.

Examples include but are not limited to:

  • Artificial heart valves
  • Implanted drug infusion ports
  • Implanted electronic device, including a cardiac pacemaker
  • Artificial limbs or metallic joint prostheses
  • Implanted nerve stimulators
  • Metal pins, screws, plates, stents or surgical staples

In general, metal objects used in orthopedic surgery pose no risk during MRI. However, a recently placed artificial joint may require the use of another imaging procedure. If there is any question of their presence, an x-ray may be taken to detect the presence of and identify any metal objects.

Patients who might have metal objects in certain parts of their bodies may also require an x-ray prior to an MRI. You should notify the technologist or radiologist of any shrapnel, bullets, or other pieces of metal which may be present in your body due to accidents. Dyes used in tattoos may contain iron and could heat up during MRI, but this is rarely a problem. Tooth fillings and braces usually are not affected by the magnetic field but they may distort images of the facial area or brain, so the radiologist should be aware of them.

Infants and young children usually require sedation or anesthesia to complete an MRI exam without moving. Whether a child requires sedation will depend on the child’s age and the type of exam being performed. Moderate and conscious sedation can be provided at Newark Beth Israel Medical. A physician specializing in the administration of sedation or anesthesia to children will be available during the exam to ensure your child's safety. You will be given special instructions how to prepare your child for the sedation or anesthesia.

Information on MRI and other types of MRI exams

Preparing for a Pelvic Ultrasound

  • You should wear comfortable, loose-fitting clothing for your ultrasound exam. You may need to remove all clothing and jewelry in the area to be examined.
  • You may be asked to wear a gown during the procedure.
  • Ultrasound examinations are very sensitive to motion, and an active or crying child will slow the examination process. To ensure a smooth experience, it would be beneficial to explain the procedure to the child prior to the exam. You may bring a book to read to the child to ease anxiety. Ultrasound departments often have a television in the examination room and the child's favorite show may be played if there are no other available distractions.
  • Abdominal and retroperitoneal exams: don’t eat 4-6 hours before your appointment.
  • Bladder and pelvic exams: drink a minimum of 30 ounces of water starting 1 hour before your appointment time.
  • Bladder and pelvic exams: avoid urinating 1 hour before your appointment time.
  • Take your medications as usual, with small sips of water.
  • Arrive 30 minutes before your scheduled appointment.

Information on Pelvic Ultrasound

Prepare for a Sonohysterography (Ultrasound of the Uterus)

You should wear comfortable, loose-fitting clothing for your ultrasound exam. You may need to remove all clothing and jewelry in the area to be examined. You may be asked to wear a gown during the procedure.

It is best to perform sonohysterography one week after menstruation to avoid the risk of infection. At this time in the menstrual cycle, the endometrium is at its thinnest, which is the best time to determine if the endometrium is normal. The timing of the exam may vary, however, depending on the symptoms and their suspected origins. Sonohysterography should not be performed if you are pregnant.

No special preparation is required prior to the exam. You may be advised to take an over-the-counter medication shortly before the procedure to minimize any potential discomfort.

Information on Sonohysterography

Preparing for an Upper Gastrointestinal (GI) Tract Radiography

Your physician will give you detailed instructions on how to prepare for your upper GI. You should inform your physician of any medications you are taking and if you have any allergies, especially to barium or iodinated contrast materials. Also inform your doctor about recent illnesses or other medical conditions.

Women should always inform their physician and x-ray technologist if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to radiation. If an x-ray is necessary, precautions will be taken to minimize radiation exposure to the baby.

To ensure the best possible image quality, your stomach must be empty of food. Therefore, your doctor will likely ask you not to eat or drink anything (including any medications taken by mouth, especially antacids) and to refrain from chewing gum after midnight on the day of the examination.

You may be asked to remove some or all of your clothes and to wear a gown during the exam. You may also be asked to remove jewelry, removable dental appliances, eye glasses and any metal objects or clothing that might interfere with the x-ray images.

Information on Upper GI imaging

Information on diagnostic X-Ray & other X-ray exams

Preparing for an Ultrasound Imaging of the Breast

You will be asked to undress from the waist up and to wear a gown during the procedure.

  • Abdominal and retroperitoneal exams: don’t eat 4-6 hours before your appointment.
  • Bladder and pelvic exams: drink a minimum of 30 ounces of water starting 1 hour before your appointment time.
  • Bladder and pelvic exams: avoid urinating 1 hour before your appointment time.
  • Take your medications as usual, with small sips of water.
  • Arrive 30 minutes before your scheduled appointment.

Information on Ultrasound imaging

Information on other types Ultrasound imaging

Preparing for a Voiding Cystourethrogram

You should inform your physician of any medications your child is taking and if he or she has any allergies, especially to contrast materials. Also inform your doctor about recent illnesses or other medical conditions.

Your child does not need to fast or wear special clothing. Explain to your child what will happen during the examination so that there will be no confusion about what is expected. Your child will have to remove all clothing and wear a gown.

Information on voiding cystourethrogram