CT Scanning

A CT scan is an imaging investigation using X-Rays.

It is a performed on a specialised scanner which gives detailed cross sectional images of the body. This helps us to look at your body more accurately than is possible using ordinary X-Rays. 

CT Scans

All outpatients that have been booked appointments for attending the department for a CT scan will have received a copy of the CT information leaflet with their appointment letter.

This is a generic leaflet. For more specialised CT examinations, there are more detailed leaflets provided.

Where is the CT scanner?

The CT scanning department has two locations; the main one is in radiology on Level B of the hospital, and there is an additional one in the St Luke’s Wing on Level A – your appointment letter will clearly indicate which one your scan has been booked at. 

There is limited parking at St Luke’s, so alternative parking can be found in the hospital’s main car park.

You will be required to book in at front reception in both areas (although if your scan is after 17:00 or at the weekend, there will be signage for you to follow).

You will then be directed to the waiting area where either a volunteer will see you, or a radiographer will come out to you.

How can a CT help?

The CT scan enables diagnosis and follow-up of many disorders, diseases and injuries affecting the body’s tissues and internal organs.

Your doctor will have explained to you why you need to have a CT scan.

What are the risks of having a CT?

All treatments and procedures have risks, so we will talk to you about the risks of having a CT scan.

Like any X-Ray examination, this test uses radiation but we will keep the radiation dose for your examination as low as we possibly can.

Many CT examinations involve having a contrast media (X-Ray dye) injected. There is a small risk of a reaction to the contrast, but before we proceed we ask you a number of safety questions in order to identify whether you are at risk of an adverse event occurring.

The contrast media we use is iodine based. Please inform staff if you have had any previous reactions to iodine based dyes. 

There is also a small risk of extravasation of the x-ray dye which means the dye can leak from the vein into the surrounding tissues.

We try to minimise such a risk by means of testing the vein prior to use. 

What will happen if I choose not to have a CT?

The doctor that has referred you for the CT scan will discuss with you any alternative tests that are available.

What alternatives are available?

Other scans available include MRI or ultrasound, but these may be not suitable depending on the area of the body to be scanned. Some patients are unable to have MRI scans if they have pacemakers, or some other types of metallic or electronic implants.

How should I prepare for a CT?

You will be sent specific preparation instructions with your appointment letter which will relate to the area of the body to be scanned.

For some scans, patients are asked not to eat anything for a few hours before the scan. This is because an injection of contrast media will be given during the scan.

Unless you have been told otherwise, you may eat and drink normally before the scan. If you are diabetic, it is advisable to bring some food with you to have after the scan. You do not need to stop taking any of your medication either before or after the scan.

If you take any medication, please continue to take this as normal.

Asking for your consent:

We want to involve you in all the decisions about your care and treatment. If you decide to go ahead with the CT scan, by law we must ask you to consent to the test.

This confirms that you agree to have the procedure and understand what it involves. The doctor that referred you for the CT scan will explain the risks, benefits and any alternative tests. If you are unsure about any aspect of your CT scan, please do not hesitate to speak to either your doctor, or the radiographer who will carry out the CT scan.

If a translator is needed, please contact the department with the necessary requirements prior to the appointment.

What happens during a CT?

Depending on the area of your body being scanned, it may be necessary for you to drink some water.

For some scans you may be asked to change into a gown, depending on the area of the body to be scanned. This will require you to undress down to your underwear, and put on a gown.

Necklaces & chains will need to be removed, as will any bras with wires. You may bring your own gown if you wish, as long as the garment has no metallic zips, buttons or hooks.

You may also need an injection of contrast for the scan. This is a special X-Ray dye which shows up the blood vessels and organs on the scan.

If required for the scan, a member of staff will insert a cannula in your arm and ask you some questions regarding allergies and other relevant medical history.

You will lie on a bed and the scan involves passing through the scanner several times. You may be asked to breathe in and hold your breath. The breath holds are not long, often only for a few seconds at a time.

If needed, the contrast will be connected to your cannula and injected during the course of the scan. This can make you feel warm, give a metallic taste in the mouth and may give a sensation like you are going to the toilet.

These are only sensations, and won’t last very long. The CT scan usually takes around 10 minutes with you in the room.

Who will perform the CT scan?

Your scan will be performed by radiographers and you may be assisted by a radiology department assistant.

Some procedures may involve a radiologist and nurse, and as we are teaching hospital, there may be some students in attendance.

What should I expect after a CT?

You can generally leave straight away. If you had an injection of contrast media for the scan, the cannula will be removed from your arm before you leave.

There should be no lasting effects from the contrast.

How will I get my results?

Your scan will be reported by a radiologist and the report will be sent back to the doctor who referred you for the scan for your next outpatient appointment.

They will not usually be sent back to your own GP.

CT Coronary Angiograms (Cardiac CT)

All patients that have been referred for a CT Coronary Angiogram will receive copies of our CT Coronary Angiogram information leaflet when they receive their appointment letter.

Before the scan

You will be referred for this test by one of the clinicians in the hospital; they will send a request to the CT bookings clerk who will send out an appointment for you. There may be scope to change this appointment time if it does not suit you.

Please contact the radiology department before your scan if you are:

  • Pregnant
  • Asthmatic
  • Allergic to iodine or x-ray dye
  • Diabetic and taking metformin
  • Have an underactive thyroid and are taking thyroxine

You will need to have someone to drive you to and from the hospital for this test. This could be a friend or relative.

For their safety, your relative or friend will not be able to accompany you into the examination room.

For a 24 hour period before your scan, you must not take:

  • Food or drinks that contain caffeine, such as tea, coffee, fizzy drinks and chocolate
  • Stimulant medicines such as antihistamines, decongestants or pain relief containing caffeine

Please do take any other medicines that you need unless otherwise instructed.

It is important that you are as relaxed as possible before your scan, as this helps to keep your heart rate low and results in clearer images.

Caffeine and certain medicines can raise the heart rate, meaning we will be unable to scan you.

At your appointment

You will be given a gown to wear during the scan. Metal objects, such as necklaces and bra fastenings, affect the images and must be removed prior to the examination while you are changing.

You will then be taken to a private area where a radiology nurse will ask you some questions about your health, medications you might be taking and take your heart rate and blood pressure using a monitor.

If your heart rate is too fast to scan your heart clearly, you may be given some medication before and during your scan. This slows your heart rate and results in much more accurate images.

A cannula will be placed into a vein in your arm and through this you will receive the injections of dye during your scan.

What will happen during the scan?

You will be taken into the CT scanning room where your identity will be checked. The radiographer will explain the procedure to you and answer any questions you might have.

If you agree to have the scan, you will be asked to lie down on the couch. You will be attached to the heart rate monitor and the pump which injects the dye through the cannula.

At this point you may be given a tablet of glyceryl trinitrate (GTN) to place under your tongue. The GTN relaxes the vessels around the heart, enabling them to be imaged more clearly. You may find that the tablet doesn’t dissolve completely so it can be swallowed or spat out after the procedure is finished. A checklist will be completed to ensure this is suitable for you.

The couch will be moved slowly to position your chest within the scanner. The radiographers will retire to the control room they but will be able to hear you talk over the intercom and see you throughout the scan.

During the scan, the couch will move in and out of the machine a few times.

You will need to hold your breath at certain times during the scan. This is very important in order to ensure clear and accurate images. The radiographers will explain the breathing instructions to you.

The radiographers will tell you over the speaker before you receive the injection.

When the dye is injected it is common to experience a ‘hot flush’ sensation, particularly across the neck and chest. This feeling goes away quite quickly and is normal.

Many people experience the hot sensation around the rest of the body. Some people also get a metallic taste in their mouth.

The actual scan normally takes about twenty minutes however because of the preparation i.e. heart rate control and cannulation, the length of stay in the department can be 1-2 hours.

Sometimes there may be further delays in the department due to emergency cases which may result in you being seen later than your appointment time. We try to keep patients informed of any delays where we can.

What happens after the scan?

The cannula will be removed. You will be asked to wait in the department for at least 30 minutes if you had medication whilst in our care. During this time a nurse will check your heart rate and blood pressure.

Following the scan, you can eat and drink normally. You will not be able to drive yourself home.

The radiologists and the cardiologists will report the scan pictures and you will be able to discuss the results with your cardiologist during your next clinic appointment.

CT Colonography (CTC)

All patients that have been referred for a CT Colonography or Virtual Colonoscopy will receive copies of our CT Colonography information leaflet, and our Bowel Preparation information leaflet when they receive their appointment letter.

Before the scan

You will be referred for this test by one of the clinicians in the hospital who will send a request to the CT bookings clerk who will send out an appointment for you.

There may be scope to change this appointment time if it does not suit you.

Appointment times maybe before 08:00 and on arrival the doors to radiology may be shut, however the radiographers are aware and will come and get you from the seats opposite by the lifts.

You will be required to take some bowel preparation prior to the scan. The clinician will prescribe this and will either give you the prescription directly to collect from the hospital pharmacy or it will be attached to your CT request.

The CT bookings clerk will collect the prescription from the hospital pharmacy and you will need to collect from them.  When you are informed of your appointment, you will be told where to collect your preparation from.

Please read the bowel preparation leaflet and follow the instructions for the bowel preparation and diet as doing so will give the biggest potential for a diagnostic scan.

At your appointment

On arrival at the radiology department, you will book in at reception and be sent to the waiting area. Either a volunteer will greet you or a radiographer will come out to see you.

They will get you changed for your scan. This will involve removing all of your clothes and putting on a pair of special shorts, and two hospital gowns.

Once in the scanning room, one of the radiographers will explain the procedure to you and ask you questions about your suitability to be given two injections. One is a muscle relaxant called Buscopan®; the other is an Iodine based contrast dye.

Your scan will be performed by either a Radiologist or a CTC Radiographer.

Further details of the scan may be found in the information leaflet.

After the scan

You will be kept in the department for a short period of time following your scan to ensure that you are feeling OK before going home. In this time we will leave the cannula in situ and give you some reading material.

After about 10 minutes, either a radiographer or a radiology department assistant will come to check that you are feeling ok, remove the cannula and allow you to dress and go.

Following the scan, you may go back to eating and drinking normally however we would recommend drinking a bit more water to re-hydrate the body.

The results of the scan will not be available to you on the day. The scan will be reported by a radiologist and sent to the referring clinician that requested the scan.

They will be in contact with you in due course to give you an appointment for the results.

CT Guided biopsy

All patients that have been referred for a CT Guided Biopsy will receive copies of our CT Biopsy information leaflet when they receive their appointment letter.

What is a CT guided biopsy?

A needle biopsy is a way of taking a small piece of tissue out of your body using only a tiny incision, so it can be examined under a microscope by a pathologist: an expert in making diagnoses from tissue samples.

Because this biopsy is done through the skin, it is called a percutaneous biopsy.

Before the scan

You will be referred for this test by one of the clinicians in the hospital & they will send a request to the CT bookings clerk who will send out an appointment for you.

There may be scope to change this appointment time if it does not suit you.

Please ring the radiology department if you:

  • Take warfarin, aspirin and Clopidogrel or anything that thins your blood
  • Are diabetic

You will have been allocated a day bed on the Medical Day Unit (MDU), Day Surgery Unit (DSU) or the Surgical Short Stay Unit (SSSU).

The location will be written on the appointment letter accompanying this patient information leaflet.

You will be asked to attend the ward three hours prior to your appointment to allow bloods to be taken and the results available prior to the procedure.

You will be asked not to eat for four hours but can drink water up to one hour prior to the procedure, unless otherwise advised.

You will be asked to put on a hospital gown and a cannula will be placed in a vein.

If you have any allergies, you must let the staff looking after you know. If you have previously reacted to intravenous contrast medium (the dye used for kidney x-rays and CT scans) then you must tell the radiographers.

Can I bring a relative or friend?

Yes, but for reasons of safety, they may not be able to accompany you into the examination room except in very special circumstances.

You must have someone to collect you and drive you home after your four hours bed rest and you will need to have someone with you overnight.

What will happen during the biopsy?

Before being taken into the scanning room the radiologist who is performing the procedure will ask you for your consent. If you have any questions regarding your procedure, now is a good time to ask.

You will be asked to lie on the CT scanning table, in the position that the radiologist has determined is most suitable.

If you have not already had a cannula placed in the back of your hand or arm, then one may be inserted at this point.

The radiologist will keep everything as sterile as possible, and may wear a theatre gown and operating gloves. Your skin will be cleaned with antiseptic, and you will be covered with a sterile drape.

The radiologist will use the CT scans to decide on the most suitable point for inserting the needle.

The radiographers will accurately mark this point with an indelible pen using the centring lights on the scanner to guide them.

Your skin will then be anaesthetised, and the biopsy needle inserted into the abnormal tissue.

While the first part of the procedure may seem to take a while, actually performing the biopsy does not take very long at all, using the CT scans to accurately guide the needle into position.

You must keep as still as possible during this stage, if it becomes too uncomfortable please let us know.

Will it hurt?

Most biopsies do not hurt at all, although unfortunately bone biopsies may be painful. When the local anaesthetic is injected, it will sting to start with, but this soon passes off and the skin and deeper tissues will soon feel numb.

Later, you may be aware of the needle passing into your body, but this is generally done so quickly, that it does not cause any discomfort at all.

There will be a nurse and radiographer looking after and monitoring you throughout the procedure.

How long will it take?

Every patient’s situation is different, and it is not always easy to predict how complex or how straightforward the procedure will be.

It may be over in thirty minutes, although you may be in the x-ray department for about an hour altogether.

What happens after the scan?

You will be taken back to your ward on a trolley accompanied by a nurse.

Nurses on the ward will continue to carry out observations, such as your heart rate and blood pressure to make sure there are no problems.

You will stay in bed for four hours until you have recovered and allowed to go home.

If you have a lung biopsy, it is routine to have a chest x-ray prior to going home.

What happens next?

All being well, you will be allowed home either on the same day, or the next.

Do not expect to get the results of the biopsy before you leave, as it always takes a few days for the pathologist to complete all the necessary tests on the biopsy specimen.

CT Guided Drain

All outpatients that have been referred for a CT Guided Drainage will receive copies of our CT drainage information leaflet when they receive their appointment letter.

What is a CT guided drainage?

An abscess is a collection of pus that has built up within the tissue of the body. The main symptoms and signs of an internal abscess include pain in the affected area, a high temperature, and generally feeling unwell.

Internal abscesses rarely heal themselves, so prompt medical attention is indicated if such an abscess is suspected.

In the past, drainage of an abscess inside your chest or abdomen would have required an open operation.

Now it is possible to drain collections by inserting a plastic tube(s) called a drainage catheter, into the abscess/collection through the skin, with only a tiny incision.

This procedure is called percutaneous (through the skin) abscess drainage.

Before the scan

You will be referred for this test by one of the clinicians in the hospital; they will send a request to the CT bookings clerk who will send out an appointment for you.

There may be scope to change this appointment time if it does not suit you.

Please ring the radiology department if you:

  • Take warfarin, aspirin and clopidogrel, or anything that thins your blood
  • Are diabetic

You need to be an inpatient in the hospital.

Your doctors will need to have taken blood for clotting, platelets and renal function and the results must be available prior to the procedure.

You will be routinely screened for MRSA (Methicillin-resistant Staphylococcus aureus) prior to the planned procedure.

You will be asked not to eat for four hours but can drink water up to one hour prior to the procedure, unless otherwise advised.

You will be asked to put on a hospital gown and a cannula will be placed in a vein.

If you have any allergies, you must inform the staff looking after you.

If you have previously reacted to intravenous contrast medium (the dye used for kidney x-rays and CT scans) then you must tell the radiographers.

What actually happens during a percutaneous abscess/collection drainage?

Before being taken into the scanning room the radiologist who is performing the procedure will ask you for your consent. If you have any questions regarding your procedure, now is a good time to ask.

You will be asked to lie on the CT scanning table, in the position that the radiologist has determined is more suitable.

If you have not already a cannula placed in the back of your hand or arm, then one may be inserted at this point.

The radiologist will use the CT scan images to decide on the most suitable point for inserting the drainage catheter.

The radiographers will accurately mark this point with an indelible pen using the centring lights on the scanner to guide them.

The radiologist will keep everything as sterile as possible, and may wear a theatre gown and operating gloves. Your skin will be cleaned with antiseptic, and you may be covered with a sterile drape.

Your skin will then be anaesthetised, and the biopsy needle inserted into the collection.

What happens next will vary in different situations. Any pus may simply be drained through the needle (aspirated), or a slightly larger needle or plastic tube, which is then withdrawn altogether.

Alternatively, it may be necessary to place a larger drainage tube (catheter) into the collection and attach it to the skin, with a special dressing, so that the pus can continue to drain for several days.

While the first part of the procedure may seem to take a while, actually performing the percutaneous drainage does not take very long at all, using the CT scans to accurately guide the needle or catheter into position.

You must keep as still as possible during this stage, if it becomes too uncomfortable please let us know.

Will it hurt?

Most percutaneous drain insertions are uncomfortable for a short period of time.

When the local anaesthetic is injected, it will sting to start with, but this soon passes off, and the skin and deeper tissues will soon feel numb.

Later, you may be aware of the needle, or the wire and catheter, passing into the collection(s) and sometimes this is painful.

There will be a nurse and radiographer looking after and monitoring you throughout the procedure.

 How long will it take?

Every patient’s situation is different, and it is not always easy to predict how complex or how straight forward the procedure will be.

It may be over in twenty minutes, depending on the complexity and number of percutaneous drains to be inserted.

What happens afterwards?

You will be taken back to your ward on a trolley accompanied by a nurse.

Nurses on the ward will continue to carry out observations, such as your heart rate and blood pressure to make sure there are no problems for several hours post procedure.

You will generally stay in bed for a few hours, until you have recovered.

If the drainage catheter has been left in your body for the time being, then it will be attached to a collection bag. It is important that you try and take care of this.

You should try not to make any sudden movements, for example getting out of a chair without remembering the bag, and making sure that it can move freely with you.

It may need to be emptied occasionally, and the catheter may require flushing with a saline solution.

How long will the catheter stay in, and what happens next?

These are questions which only the doctors looking after you can answer.

It may only need to stay in a short time. It is possible that you will need further scans to check that the collection has been drained satisfactorily.

You will be able to lead a normal life with the catheter in place, and when the catheter is removed there is generally only slight discomfort.

Contact us

For appointment enquiries please contact:

01483 571 122 ext. 4414/4151

Between 08:30-16:30