A 24-hour service is available to patients referred by the Accident and Emergency Department, throughout the year.
The BNHH service offers, As well as routine in and outpatient scanning, offering specialist imaging in the form of CT coronary angiography, CT colonography and interventional CT procedures (biopsies and oncological treatments).
The RHCH service provides general cross-sectional imaging and some specialist scans such as CT Cardiac and CT Virtual Colonoscopy.
NB: If there is a possibility that the patient might be pregnant the CT Department must be made aware of this as soon as possible and when applicable, in advance of the appointment.
CT scans use X-rays, a CT scanner and a specialised computer to create detailed images of the inside of the body.
CT scans are sometimes referred to as CAT scans (Computerised Axial Tomography).
Detailed images of many structures inside the body, including the internal organs, blood vessels and bones are produced by CT scans. They can be used to:
- Detect bone and joint problems
- Show any internal injuries and bleeding, for example, after a car accident.
- CT scans can be compared to establish if certain treatments are working for example, showing if scans of a tumour over time, are responding to chemotherapy or radiation therapy.
- Identify if a condition is changing over time.
- Guide treatment plans and procedures such as biopsies and radiation therapy.
CT scan images are formed by a narrow beam of X-rays circling around the part of the body that has been requested. This provides a series of images from many different angles that the computer uses to create a cross-sectional image. This process is repeated to produce a number of ‘slices’ that the computer then uses to create a detailed image of the organs, bones or blood vessels. Each slice takes approximately one second to produce; depending on how much of the body is to be scanned the whole examination will only take a few minutes.
In a CT scan, dense areas such as bones are easy to see but soft tissues may look faint in the image. To help them appear clearly a special high density contrast agent ‘dye’, known as contrast media, may need to be used to highlight blood vessels, organs and other soft tissue structures.
The contrast media is inserted into the body in one of three ways:
- Injection into a vein to enhance the blood vessels, urinary tract, liver or gallbladder.
- Drinking a liquid contrast media can enhance the digestive tract.
- Rectally if the intestines are being scanned.
After the introduction of the contrast media the scan will highlight the required areas.
What is MRI?
Magnetic Resonance Imaging (MRI) uses a very powerful magnetic field and radio waves together with an advanced computer system to build highly detailed images of the soft tissues.
If there is a possibility that the patient might be pregnant the MRI Department must be made aware of this as soon as possible and when applicable, in advance of the appointment.
Each MRI image shows a thin ‘slice’ of the part of the body being examined.
The magnetic field can cause harm if the patient has anything metallic, magnetic or electrical inside or attached to the outside of the body. The MRI staff MUST be made aware of any of these BEFORE the procedure can be undertaken.
If the patient has ever had a history of metal fragments in the eyes, it may be necessary to have an X-ray taken of the eyes to ensure there are no fragments left. The MRI Department will arrange this after a discussion with the requesting Consultant.
If the patient has a cochlear implant they will NOT be able to have an MRI scan.
During the procedure the patient will be lying on a couch that enters an open-ended +/- 1.3 metre-long tunnel. Earplugs or headphones will be offered to listen to a choice of music or the radio as the scanner makes a variety of very loud noises during the scan. The procedure of taking the images will usually take between 30 and 90 minutes.
