I did my PET Scan Tuesday, March 26th 2007,
Let me take you through the whole procedure and let me put to rest any thoughts you might have that it might be harmful, unsafe, nerve-wracking or unpleasant. It will be none of these.
The reason I had a PET Scan or to give it its full name a CT-PET Scan was to try to identify why my brain functions were not performing correctly.
Most times a PET Scan is used to identify and monitor the progress of various cancers. The procedure is costly and you can explore why a PETscan is costly. There are not many PET-CT scanners around. One of the reasons for this is that the radioactive sugar called FDG used in the scanning procedure does not travel long distances.
So it is ideal to have the PET scanner close to the laboratory where the FDG is produced. The FDG is produced in a Cyclotron.
I live in Johannesburg South Africa and there is, at the time of writing this page, only one PET scan - CT scan unit in the country. It is about 6 kms from my home at the Linksfield Clinic. I believe there is a PET Scanner system coming to Cape Town soon since there has been an FDG Cyclotron production unit built at Faure.
It has a long name ... Positron Emission Tornography.
In preparation for a PET Scan you will be told to drink quite a lot of water during a 16 hours period prior to the PET Scan itself.
You will be asked not to eat anything for 12 hours before the PET Scanning procedure.
You will be given a very specific time for the PET Scan because the radio-isotope has a definite and specific life span. Read the FDG information.
The first stage involves an injection of a radio-isotope (FDG) into the blood circulation. This is done through a saline drip.
The radioisotope is called FDG, It is a very specially prepared sugar. Read about FDG here.
After being injected with the FDG (completely painless with the exception of the prick to install the saline drip.) you will be required to rest for one hour. You will be probably be placed in a special room close to the PET Scanner. The room is remote from other locations in the PET Scan centre because of the radiocative status of the FDG. In my case it was just a pleasant room with a comfortable bed on which I lied for an hour.
During the hour the body is metabolizing the FDG just like any normal sugar.
Once the hour is up you will be taken to the CT/PET Scanner. This is a dual camera system. The first part of the system is a CT Scanner. If you look at the image above (Siemens CT/PET) you will notice that there are 2 sections to the scanner ... the first section is the CT scanner.
You will be lying on your back and will be rolled into a wide tunnel. There is very little fear of claustrophobia. If you've ever had an MRI Scan you will know that the MRI chamber can be a little claustophobic.
The PET Scan CT Scanner is a piece of cake compared to the MRI scanner tunnel. You will have lots of space and there is very little noise.
You will be under observation all the time but there is nothing at all to worry about.
In my case the CT scan took about 10 minutes or so. When the CT scan was finished I was rolled a bit further back into the PET Scanner chamber. The CT scan creates a physical static image of every section of the brain.
The PET Scan is very different. The PET scanner takes a "movie" of the metabolic or biochemical process happening in the area being investigated. In my case the head was the area under investigation but it could be the breast, kidney or the whole body.
The PET scan also takes about 10 minutes or so ... I didn't time it.
That's it. You're rolled out from the scanner and told to go home.
The image shown was taken from a Google search.
The magic of a PET-CT scan is the ability to match a metabolic "action movie" to a physical bodily location. Take a look at the image. The PET is the movie, the CT is the static image.
The Siemens PET/CT scanner (I think it was a Siemens unit) take images of a patient’s bodily structure and biochemistry, respectively. The two images are then superimposed. The layered images give a single composite image that provides the radiologist and the specialist doctor (oncologist or neurologist) much more information than can be obtained from an MRI or CT scan.
In this way the doctor can see exactly what is happening to the bodily function at the exact location of the body.
They can then make a more accurate diagnosis.
A PET-CT scan is an amazing bit of nuclear medicine. It enables very specific diagnoses to be made. It is state of the art medicine.
Most people are not aware of the magic of the FDG, PET-CT dual camera images nuclear medicine miracle worker.
You know ... that's why you reached this point.
It is magic in the making. It is a revolution a-coming to all parts of the medical fraternity.
I'm a 63 years old chemical engineer. I'm in a position that I can understand the technology and I could afford the PET-CT scan.
I'm lucky.
The FDG ticks away. In 110 minutes time there will only be half left and a further 110 minutes later the FDG will be halved again. And 110 minutes later it will be halved again. Hurry up! Not much time left.
Do not be late for your appointment.
For the next 24 hours or so you will be mildly radioactive. No danger involved.
You will be told to keep away from small children and pregnant women for 24 hours.