Thursday, April 20, 2006
Improving technology means more accurate medical tests

By Dr. Anthony Policastro
Nanticoke Memorial Hospital,
Medical director

When I was growing up, my mother played 78 RPM records. Then vinyl came along. Record albums and 45 RPM records were the new thing. Then came cassette tapes. Some people had 8-track tapes. These were followed by CDs. Now we have DVD-audio. Technology keeps on advancing. With each new technology came better sound. Medicine is the same way. There are many areas that benefit from improvements in technology. One of those areas is radiology. X-ray machines used to take pictures like cameras. There was an X-ray film. It needed to be developed. There was then an X-ray picture to view. Some pictures were better than others. For example, the X-ray machines in the radiology area took good pictures. The X-ray machines that were wheeled to the inpatient area took pictures that were not as clear. Now the pictures are digital. We can take them by digital methods. We can view them by digital methods. We can send them by digital methods. These are all improvements. They allow clearer pictures. They allow more information to be seen. The same thing is true of ultrasound machines. At one time, ultrasound machines saw very rough images. The size of a baby was about all they could tell. They improved over time. The images got better. Now, there are many things that can be seen on ultrasound. Parents proudly come home with pictures of their unborn infant to show the whole family. That was not possible in the past. CT scanners have a similar history. CT scanners were developed when I was still a pediatric resident in the 1970s. Over time CT scanners improved. The ability to see things also improved. The most recent improvement is what is called a multi-slice CT scan. The older CT scanners were single slice image. The new ones started with two slices. They went to four-slice image. Many areas now have 8-slice images or 16-slice images. These show great detail.

Soon we will see 32-slice images and 64-slice images. These images will be extremely clear. They will allow people to have a colonoscopy done by CT scan. That is always a popular thing for people to hear. They figure all they need to do is go to the X-ray department and get a picture taken. It is not quite that easy. One thing that people do not like about colonoscopy is the fact that the bowel needs to be cleaned. For a CT colonoscopy, the bowel will still need to be cleaned. The purpose of colonoscopy is to find polyps before they become cancerous. Regular colonoscopy detects all polyps. CT colonoscopy detects the larger ones only. Therefore, there it is an individual decision as to which is the best way. 64-slice CT scanners are clear enough to look at coronary arteries. This means that some patients with coronary artery disease might not need to have a heart catheterization. Their CT scan might show so much blockage that they might go straight to a cardiac surgeon. It also means that more people will get this kind of scan. Those who do not have any symptoms might need further examination. They might need a heart catheterization. Thus some people may get to skip a catheterization. Others might get one done even though they do not have any symptoms. MRI scanners have also improved over time. The size of the magnet is what is important. Magnets are measured in Tesla units. The older magnets had 0.5 Tesla units or less. The newer ones have as much as 1.5 Tesla units. The more Tesla units a machine has, the clearer the image. You still can pull out your old records and play them. They may not sound as clear as your new CD. Things have changed over time. You can still get your X-rays done with older technology. The pictures may not be as clear. Things have changed over time. Make sure you inquire about the equipment when you get a radiology test done. If you go through the test, you should expect to get as clear a result as possible.