Diagnostic Imaging Services

Many different procedures are performed in the Diagnostic Imaging Department that allow health care professionals to see inside a person's body. These procedures include:

• Bone Densitometry
• Computed Tomography (CT) Scan
• ERCP
• Magnetic Resonance Imaging (MRI)
• Mammography
  - The Ontario Breast Screening Program (OBSP)
  - Breast self-examination
• Nuclear Medicine
  - Nuclear Stress Test or Thallium Heart Scan
• Ultrasound
• X-Rays
  • Arthrogram
  • Barium Enema
  • Barium Meal
  • Hysterosalpingogram (HSG)
  • Intravenous Pyelogram (IVP)
  • Voiding Cystogram
    

Using advanced computers and other sophisticated equipment, the above procedures provide doctors with images of the inside of a person's body on hard copy photographs (such as X-rays), or computerized pictures that can be viewed on a monitor, as is the case with a CT scan or an MRI. At times, a contrast agent or dye is used to highlight blood vessels and to enhance the tissue structure of specific organs (such as the brain, liver, and kidneys) to assist in determining the location of the disease or injury. Depending on the procedure, the contrast agent can be introduced into a person's body in different ways: orally (by mouth), by enema, or by injection into a vein.

At Southlake Regional Health Centre all diagnostic examinations are performed by highly trained individuals called "technologists". The images generated by the technologists are then analyzed by specially trained doctors called "radiologists." This process can take anywhere from a few days to one week to complete. It is the responsibility of the radiologist to communicate the results of a patient's diagnostic imaging procedure to their referring doctor. It is then the responsibility of the referring doctor to discuss the results with their patient.

Special Notes:
A physician's referral is required for all tests and procedures performed in the Diagnostic Imaging Department at Southlake Regional Health Centre, with the exception of the Ontario Breast Screening Program.

Women who are pregnant or think they may be pregnant should notify their referring doctor and the technologist BEFORE proceeding with any diagnostic imaging examination.

Bone Densitometry

More information:
(905) 895-4521 extension 2665

Bone densitometry is a test that measures bone density and the mineral content of bone in a person's body. The test is safe, accurate and painless. Radiation exposure during bone densitometry is extremely low. During the test, the patient is required to lie still on a table while the equipment scans two areas, the lumbar spine and hip. The test is extremely helpful in diagnosing and evaluating osteoporosis (a progressive decrease in bone density that makes bones weak and fracture easily).

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CT Scan

More information:
(905) 895-4521 extension 2665

Computed Tomography (CT) scans combine the use of a digital computer with a rotating X-ray device to create detailed cross-sectional images or "slices" of the different organs and body sections. These slices are then assembled in two-dimensional, high-resolution images by a computer.

CT has the unique ability to present an image of a combination of soft tissue, bone, and blood vessels. For example, a conventional X-ray image of the head can only show the dense bone structures of the skull, whereas a CT image of the head allows physicians to also see soft tissue structures, such as the brain and blood vessels.

In a CT Scan of the abdomen and pelvis, a contrast agent is administered orally in order to highlight the stomach and bowel (digestive tract). To highlight blood vessels, it may be necessary to inject the contrast agent into a vein.

Special Notes:
CT imaging is considered safe. The diagnostic benefit of a CT scan outweighs the risks of X-ray radiation exposure or injections of contrast media.

If necessary, sedatives can be prescribed before the scan.

Patients should inform the radiologist or technologist if they have a history of allergies (especially to certain medications, and previous contrast injections), diabetes, asthma, a heart condition, or kidney problems.

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ERCP - content currently being developed

Magnetic Resonance Imaging (MRI)

More information:
Office/Technologist
(905) 895-4521 extension 2665 or 2537

MRI is a safe and painless way of taking pictures of soft tissues of the body. Especially valuable in diagnosing brain and nervous system disorders, cardiovascular disease, and cancer, the MRI's detailed images provide greater accuracy in detecting certain disease. MRI requires no

Special Note
An MRI examination CANNOT be performed on persons who have:
- a pacemaker
- cerebral aneurysm clips

It is important that your referring physician be aware of any prior surgeries you have had or if you have ever had any metal fragments in your eyes.

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Mammography

More information:
(905) 895-4521 extension 2471

Mammography is a procedure that can detect abnormalities in breast tissue when they are still too small to be felt. It is an X-ray examination that involves a minimal exposure of radiation.

For this procedure, the individual will be asked to put on an appropriate gown. The technologist will explain how the procedure is done, review the individual's brief medical history, and answer any questions. The individual will be asked to stand in front of the mammography machine. The technologist will need to compress each breast for a few seconds while the X-ray is being taken. This should not be painful, although it will be uncomfortable. Compression is extremely important as it provides a much clearer picture of the breast by separating the tissue. The compression does not damage the breast and produces no long-term discomfort. On occasion, mild bruising may occur.

The examination takes approximately 30 minutes to perform.

Usually four or more films are taken of the breasts, although it is not unusual for the radiologist to ask for more pictures or an ultrasound of the breasts in order to see all areas clearly.

Although mammography is one of the best methods of detecting breast cancer, thorough diagnosis may require additional methods of examination. Individuals at risk (women with a positive family history or dense breasts) are advised to carry out regular, careful monthly breast self-examinations and also to visit their doctor routinely for a complete clinical examination.

The Ontario Breast Screening Program (OBSP)
The Ontario Breast Screening Program (OBSP)

Women automatically become part of the OBSP at Southlake when they are referred for mammography services, provided they:

• are 50 years of age or older have no previous history of breast cancer
• are not experiencing symptoms
• have not had a mammogram within the last year
• have no mammographic and/or ultrasound abnormalities that are being followed
• have not had breast implants or explants

Women also have the option to refer themselves to the program provided they meet the above criteria.

In addition to receiving a mammogram, women attending the OBSP have the additional option to receive a clinical breast examination and instruction on how to perform breast self-examination with a registered nurse examiner.

Through the OBSP, women also receive a recall letter every two years for repeat screenings until they reach 74 years of age. However, those with documented risk factors, such as a positive family history or dense breasts, will receive annual recalls for screenings.

The OBSP is administered by Cancer Care Ontario through its regional
cancer centres and is funded by the Ontario Ministry of Health. All OBSP screening sites are accredited by the Canadian Association of Radiologists-Mammography Accreditation Program (CAR-MAP)-a voluntary peer-review to ensure that mammography services are performed at the highest quality necessary for the early detection of breast cancer.

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Breast Self-Examination

The following information was developed by the Ontario Breast Screening Program - a program of Cancer Care Ontario.

If you examine your breasts every month, you will get to know how they look and feel. This will make it easier to notice any changes. If you notice any of the following changes in one breast, compare it to your other breast. If you are still in doubt, have your doctor examine you as soon as possible:

• Changes in the size or shape of your breasts
• Areas of your breast that become red, feel hot, or look like an orange peel
• Dimples, creases or folds of your breast skin that are new
• Changes to your nipples or your nipple area, such as an itchy red rash
• Lumps in your breasts that were not present before
• Fluid leaking from your nipple

Check your breasts at the same time every month; about seven days after the first day of your period. After menopause, or a hysterectomy, check them on the same day every month, for example, the first day of every month.

Go to your doctor and have your breasts checked once a year.

The most important things to remember about breast self-examination are:

• Do it regularly.
• Show any unusual changes to your doctor.
• Do a complete check each time.
• MOST IMPORTANTLY, DO IT EVERY MONTH!
  

To perform a breast self-examination:

1. With your hand relaxed at your side, look in a mirror to check for changes in the size or shape of your breasts. Look for any redness, new bulges, dimples, folds or creases or skin that looks like an orange peel.
   
   
2. Raise your arms straight above your head and look for the same changes as above. Your breast tissue runs from below your collarbone to below your breasts and includes all of the area under your arms.
   
   
3. Put your hands on your hips and push in with your hands. Again look for any changes in your breasts.
   
   
4. Place one hand on your hip and rotate your shoulder slightly forward. Using the finger pads of the other hand (use the soft pads of your fingers, not the tips), check the area under your arm for any lumps. Change arms and examine the other underarm.
   
   
5. Do the next part in the shower or sitting upright in the tub. Use soapy hands as they can "feel" the tissue better. Place one arm behind your head and use the other hand to examine your breast. Remember to use the soft pads of your fingers, not the tips.
   
   
6. Think of each breast as a clock. Start at 12 o'clock right below your collarbone. Press firmly to move the tissue beneath the skin. You are feeling for any changes. At each "hour", make overlapping circles all the way down to and including the nipple. Don't forget the area under your arms. Change hands and examine the other breast.
   
   
7. Lying down with one arm behind your head, cross your free hand over your body to examine the far breast. Use overlapping circles, and examine the entire breast as described in #6. Change arms and examine the other breast. Using hand lotion may make your fingers more sensitive.
   
   
8. Roll to one side with your wrist on your forehead. Put a towel under your shoulder for support. Examine the outer side of your breast and underarm areas using overlapping circles. Examine both breasts.

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Nuclear Medicine

More information:
(905) 895-4521 extension 2665

Nuclear medicine is a safe and painless procedure. It records information about the function and structure of the major organs in the human body, unlike general radiology that creates images of dense bone structures. Common nuclear medicine applications include diagnosis and treatment of hyperthyroidism (a condition where the thyroid gland is overactive and produces too much hormone), cardiac stress tests to analyze heart function, bone scans for orthopedic injuries, lung scans for blood clots, and liver and gall bladder procedures to diagnose malfunctioning or blockages.

In nuclear medicine, a small amount of radioactive tracer is introduced into the patient to obtain images that show the function of internal organs. The dosage of the radioactive drug is carefully prescribed to allow for minimal radiation exposure while the patient is positioned under a "gamma camera". This camera detects and scans the distribution of the tracer within the patient's body. The patient does not feel anything with these drugs and by the following day, most of the radioactive tracer is eliminated from the body by normal excretion. The diagnostic benefit of such tests outweighs the risks of radiation exposure.

Special Note:
Southlake Regional Health Centre's Nuclear Medicine laboratory is inspected annually by the Atomic Energy Board of Canada.

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Ultrasound

More information:
(905) 895-4521 extension 2665

An ultrasound test is a modern medical diagnostic procedure that uses high-frequency sound waves to produce images of the organs and structures of the body. Because high-frequency sound waves cannot penetrate bone or air, they are especially useful for imaging the soft tissues and fluid-filled spaces of the human body (e.g., heart, pelvis and reproductive organs, fetus, kidneys, liver, pancreas, gall bladder, eyes, thyroid, blood vessels, arteries and veins). An ultrasound test can indicate if and when surgery is needed. It can identify and locate aneurysms, blood clots, damaged tissues, heart problems, abnormal growths, and other diseases. It also offers an accurate way to diagnose any fetal abnormalities, multiple pregnancy, tubal pregnancy, cysts, and tumors in the pelvic organs.

The equipment used is very sophisticated and the test is simple and painless. A transducer (special probe), which produces and receives silent, high-frequency sound waves, is placed against the patient's body and slowly moved over the area that is being examined. Sound waves then pass through the skin into the body. As they strike various organs, they send echoes back to a transducer. The transducer is able to separate and identify the different echoes produced by different kinds of tissue, blood, bone, and fluid. A visual presentation of varying echoes is formed on a TV screen as the transducer changes sound waves into electrical energy. The image represents a cross-section of the organ being examined. Photographs or films of the images are then taken for further study and interpretation.

Special Note:
The technologist performing the ultrasound cannot provide any results regarding the gender of the fetus in pregnant women. This information can only be provided to the woman in consultation with her referring physician.

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X-Rays

X-rays are electromagnetic radiation waves used to create images of tissues within the human body. Because of their high energy and short wavelength, X-rays are able to penetrate the body's tissues and bones. The amount of X-rays that passes through will depend on the composition and mass of the tissues. For example, bones being dense will stop more of the rays; therefore, less dense tissue, such as the lung, will allow more X-rays to pass through. After X-rays pass through the body's tissue, they are converted to light within the cassette that holds a special type of film. This explains why images of bones on an X-ray film appear white, as less energy has passed through, and images of lung tissue appear darker, as more energy has passed through. In some specialized X-ray procedures, a contrast agent is introduced into the body to highlight a specific area, such as the oesophagus, stomach, or blood vessels. The contrast agent presents a clearer and sharper outline of these structures than the conventional X-ray picture. Most X-ray procedures are painless, and may take from less than a minute to an hour or more.

The risks of radiation are known to be extremely small in modern X-ray facilities using state-of-the-art techniques and equipment. Lead "aprons" and lead shields are used to protect the reproductive organs during all X-ray procedures. However, radiation can cause irreparable damage to the fetus. Pregnant women or women who think they may be pregnant should avoid having to go through with an X-ray examination.

Other more specialized types of X-rays include:

• Arthrogram
• Barium Enema
• Barium Meal
• Hysterosalpingogram (HSG)
• Intravenous Pyelogram (IVP)
• Voiding Cystogram

• Arthrogram
An arthrogram is an X-ray examination of the joints in the human body (such as the shoulder, hip, and wrist) and is done primarily to assist in diagnosis. The radiologist injects a small amount of contrast agent into the joint being examined. After the injection, the technologist will take a series of X-rays. To ensure that the contrast agent has reached all areas of the joint space, a patient may be asked to exercise the joint and the series of X-rays may be repeated. The entire procedure takes between 30 to 45 minutes to perform. Some discomfort in the joint is normal after an arthrogram and the incidence of infection is extremely low.

Patients should inform the technologist or radiologist if they are asthmatic, diabetic, or have a history of allergies (especially to the injected contrast agent used during a previous radiology examination). To reduce the risks of a recurring allergic reaction to the above, oral steroids may be prescribed prior to the arthrogram. Patients on certain medications, such as anticoagulants (blood thinners), may have to discontinue taking them for 72 hours before the examination. Patients are advised to inform their referring doctor or the technologist of any other medical condition they may have (for example, of the heart, kidney, or thyroid), or pregnancy before the examination is performed.

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• Barium Enema
A barium enema is an X-ray examination of the colon and rectum, and is used in diagnosing cancers, polyps, etc. As these internal organs are not visible on X-rays, a contrast agent such as liquid barium is administered through an enema into the patient's rectum. The inside lining of the colon and rectum are temporarily coated with the liquid barium, thus allowing the outline of these organs to be visible on the X-ray films. To enhance visualization of the bowel, puffs of air may also be introduced that may result in the patient experiencing some abdominal cramps. During this procedure, the radiologist watches the barium flow through the bowel on a small TV monitor. After this, the technologist takes a series of X-rays while the barium remains in the bowel. A "post-evacuation" film of the empty colon may be requested after the patient has expelled the barium (after a bowel movement).

• Barium Meal
A barium meal (Upper GI Series/ESD) is an X-ray examination of a patient's oesophagus, stomach, and duodenum to determine whether there are ulcers, tumors, or any other abnormalities. In this test, the patient stands in front of an X-ray machine and will be asked to swallow some gas granules (such as Alka Seltzer or Eno) and to drink some barium liquid (contrast agent), which will provide a sharper outline of the appropriate internal structures. During the procedure, the radiologist watches images of the barium liquid flowing through the upper gastrointestinal tract on a TV monitor.

A follow-through examination-a continuation of the GI Series-will look closely at the small bowel. The patient will be asked to drink some more barium and X-rays will be taken every 20 to 30 minutes until the barium has passed all the way through the small bowel. The entire examination can last between 2 to 4 hours. During all this time, the radiologist will review the series of films to track the flow of barium from the stomach to the large intestine. Barium may cause the stool to appear light in colour. To assist with the removal of barium, the patient is advised to drink plenty of fluids.

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• Hysterosalpingogram (HSG)
A hysterosalpingogram is an X-ray examination of the uterus and is usually performed as part of an examination to find the cause of infertility.

In this procedure, the doctor first inserts a speculum (instrument used to inspect the vagina) into the vagina and then a small catheter or tube past the cervix into the uterus (womb); some contrast agent is then injected in order to obtain clearer and sharper images during the procedure. As the contrast media flows into the uterus and through the fallopian tubes, the doctor and radiologist watch on a TV monitor as a series of images are taken to ensure that the dye passes all the way through both fallopian tubes and that no blockages occur. The patient may experience some cramps during and after the procedure. After the X-ray, the patient is advised to lie down for a few minutes to allow the cramping to subside. Light bleeding or spotting for one or two days is normal after the procedure. However, if there is increasing pain or heavy bleeding, the patient should contact their referring or family doctor.

• Intravenous Pyelogram (IVP)
An intravenous pyelogram is an X-ray examination of the urinary tract, which includes the kidneys, ureters, and bladder. This test enables doctors to detect problems within the urinary tract resulting from kidney stones or tumors, bladder stones, enlarged prostate, and injuries after an accident or trauma. It also helps to identify blockages to the normal flow of urine.

During the procedure, the patient is placed on an X-ray table and a preliminary X-ray is taken. Contrast media (dye) is then injected into the vein in the arm or the back of the patient's hand in order to allow for clearer and sharper images during the procedure. A series of X-rays are taken as the contrast media travels through the urinary tract. The patient may be asked to empty the bladder, and an additional X-ray may be taken to check if any of the contrast media remains in the urinary tract.

The radiologist who reviews the films may request an ultrasound examination of the kidneys and bladder for the purpose of acquiring further diagnostic information.

Patients are advised to report to the doctor any history of diabetes (especially if they are taking Metformin or Glueophage), asthma, kidney problems, heart or thyroid conditions, pregnancy, and any allergic reactions to contrast agents in previous diagnostic X-rays.

The procedure is relatively painless and the risks of radiation exposure are minimal. On average the entire procedure takes between 45 minutes to 1 hour to complete.

• Voiding Cystogram
A voiding cystogram is an X-ray examination of the bladder and the urethra to determine if urine is flowing back up into the kidneys. A contrast agent is used to allow the bladder to be clearly visible on the X-ray films.

During the procedure, the patient is asked to lie flat on an X-ray table, while a registered nurse inserts a small catheter into the patient's bladder. As the contrast agent flows through the catheter into the bladder, the radiologist watches on a TV monitor as the camera moves over the lower part of the patient's body. When the bladder is full, the X-ray table will be moved to an upright position. The patient is then asked to void (empty the bladder) into a urine receiver bag, while the radiologist looks at the TV screen to see if any of the dye flows backwards and to check if the bladder has emptied completely. The entire procedure takes between 30 to 45 minutes to perform.

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