A Computed Tomography (CT) Scan uses X-ray equipment and computers to create detailed images of internal organs, soft tissue, blood vessels and bone. A CT Scan provides greater information and detail than a regular X-ray. The CT scanner creates these pictures by rotating around the area of your body being examined. The part of your body being examined will be positioned in the scanner opening, called the gantry.

 

CT Scans are performed by a Medical Radiation Technologist, MRT(R). These exams require a signed requisition from a physician or nurse practitioner and will be scheduled by our CT Department.

 

CT Scans are performed Monday through Friday 7:00 a.m.- 6:00 p.m. Requests for CT are arranged through a physician. To book, please call (519) 621-2333 ext. 2244.

 

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Please arrive at 15 minutes before your appointment time. If you are late, your appointment may be rescheduled. Please register at the Diagnostic Imaging Department located in Wing A, Level 1, Hallway #4 (just past the elevators from the Main Lobby/Entrance). Bring your health card and leave any valuables at home. 

 

CT scan preparation may depend on the type of scan you are having as well as the medical conditions of the patient. Diabetic patients, patients with renal disease and all patients 70 years or older must have an eGFR blood test within 90 days prior to your scheduled appointment at CMH. 

 

For most CT scans, you may continue to take your medications and drink normally before your scheduled appointment. Do not eat solid foods for 4 hours before your scheduled appointment time. You may use the washroom as needed. In addition, the following CT scans require you to follow specific instructions that may be given to you at the time you appointment is made:

 

Abdomen and/or Pelvis CT

  • Pick up a bottle of oral contrast (EZ-CAT) and instruction sheet from our DI Department at least 1 day prior to your appointment. 
  • Start drinking the oral contrast 1 hour prior to your appointment time. 

CT Colonography (CTC)

  • Specific instructions from DI will be sent to your physician or nurse practitioner. 

CT Enterography (CTE)

  • Specific instructions from DI will be sent to your physician or nurse practitioner.

Steroid Injections

  • Specific instructions from DI will be sent to your physician or nurse practitioner.
  • A family member, loved one or friend must come with you to drive you home after the procedure. 

A CT scan usually takes anywhere between 5-20 minutes and may take up to 90 minutes depending on the type of scan you are having. You may be asked to change into a hospital gown and remove any jewelry, dentures, hair pins, piercings, and other metal objects. It is recommended you wear loose, comfortable clothing.

 

Some CT scans require what’s called “contrast media” – an injection that enhances the visualization of specific organs and some may need an oral or rectal contrast. The Medical Radiation Technologist performing the exam will explain the procedures to you. If the injection of contrast media is required, your care provider may ask for specific blood work to be done in advance. If you are diabetic, over 70 years of age, hypertensive or have cardiovascular disease, renal impairment or only one kidney, blood work will be required. Consult your care provider. 

 

A CT Scan has a long table connected to a gantry which looks like a large doughnut. You will be asked to lie down on the CT table, which will move into the gantry when the images are taken. It is important you hold still so your pictures turn out well. The technologist will communicate with you from their control room through an intercom. They can also hear and see you through a window during your scan. 

 

Please note: Appointments may be delayed due to emergency patients taking priority. We do our best to stay on schedule and apologize for any inconvenience.
 

In most cases, you will return home after your exam unless you had a contrast injection. If you had an IV contrast, you will be monitored for 10-15 minutes after your scan. The IV will be removed if there are no signs of an allergic reaction. If you had oral and/or IV contrast, drink a lot of water over the next 24 hours to help flush it from your system. 

 

If you had IV contrast and you are breastfeeding, please read this brochure about Breastfeeding after IV Contrast. 

 

If you are diabetic and had IV contrast, please discuss with the technologist about medications containing metformin. Please contact your physician if you have any concerns regarding your medications. 

 

The radiologist will review your CT scan and send a report to your physician or nurse practitioner within 1 week; often sooner. Please follow up with your care provider for your results. 

Yes. It is highly recommended that you remove the device. A Continuous Glucose Monitoring Device (CGM) is a device that measures interstitial fluid glucose levels in people living with diabetes mellitus. The manufacturers of these devices strongly recommend removing the sensor prior to your medical appointment for CT to avoid damaging the sensor. Damage to this sensor could result in inaccurate readings and affect your care. 

 

If you do not want to remove the device, we will make every attempt to cover it with lead shielding. Please note that this is not a fool-proof option and damage to the sensor could still occur. It is recommended that you perform a finger-prick blood glucose test to ensure the sensor is still reading accurately after your exam.

 

Some manufacturers may offer free replacements if the device was removed for imaging tests. Questions related to your device can be directed to your family doctor, diabetic educator or the CGM manufacturer. 

A CT Scan is generally a safe diagnostic procedure. However, risks may include:

 

Exposure to radiation:

CT Scans are a type of x-ray machine. The radiation risk from medical x-rays is not well known, but believed to be very small. Your doctor or nurse practitioner has determined a CT scan is necessary for your course of healthcare. They feel the benefits of having a CT scan outweigh the risks. Patients who are or might be pregnant must inform the technologist in advance.

 

Reaction to Contrast:

Many CT scans involve oral, IV, and sometimes rectal contrast in order to increase the amount of information obtained from the scan. The IV contrast usually causes nothing more than a warm feeling passing around your body, but can cause an allergic reaction (such as itching, sneezing, hives, etc.) in a small number of people. Rarely (1-2 people out of 10,000) will someone have a serious, life threatening reaction.

 

Prior to your scan, the technologist will have a safety checklist for you to fill out before your scan. If you have a known allergy to CT IV contrast, please notify your health care team and the CT department prior to your scheduled appointment - premedication will be required. 

 

Damage to Kidney Function:

Your kidneys help remove IV contrast from your body. If you have contrast, drink a lot of water over the next 24 hours to help flush the contrast from your body, particularly if you have diabetes or kidney disease.