Health@Heart
The wonders of 64-Slice CT
The medical community is celebrating and the world in general has a good reason to rejoice over the introduction of another very useful scientific wonder, the latest one: Sixty-four Slice Computed Tomography Scanner. The popular models available are Siemen's Somatom Sensation, Philip's Brilliance, GE LightSpeed VCT and Toshiba Aquilion 64-slice CT.
Computed Tomography is about 30 years old. Since then, it has been improved a lot. In 1998, the four-slice CT was introduced. Since then, the pace has accelerated. In the past decade, CT has doubled every 3 to 4 years, with 15 to 20% growth annually. Today, more than 50 million CT exams are performed in the USA each year; worldwide is about 100 million. The new scanner will undoubtedly increase these statistics.
Why all the excitement?
The excitement when vaccination or blood tests could someday be done without a needle stick pales in comparison to the delight the new 64-slice CT has brought to humankind. With this new CT scanner, diagnosis of illnesses, including cardiovascular illnesses and cancer, to name a few, could be made in seconds, not hours or days, with no pain for the patient. This state-of-the-art scanner can "produce detailed pictures of any organ in a few seconds and provide sharp, clear, three dimensional images, including 3-D views of the blood vessels, in an instant."
How fast is this 64-slice scanner?
Compared to the typical (older "modern" conventional) CT scanner widely in use today, the 64-slice CT has four times as many detectors and combines unrivaled image quality with unbelievable speed. It can "gather a high-resolution image of the heart, brain or a pair of lungs in about 5 seconds. A total body scan (as in searching of a blood clot) takes about 30 seconds," according to the manufacturers, confirmed by physicians who have used them.
How about pictures of the beating heart?
Part of the wonderful features of this new scanner is its ability to time and take the images between contractions of the heart (like freezing motion), providing the first clear non-invasive images of the heart and the major blood vessels, without the blurring caused by the beating. The conventional way to diagnose coronary artery disease is still (in most centers) by coronary angiogram (cardiac catheterization), where a spaghetti-size catheter is inserted thru the groin artery and directed to the artery of the heart, for visualization for any blockage(s) that may cause a heart attack. This is done with sedation, with a big needle stick, and takes about 30 minutes or so, and a day or so hospitalization. The 64-slice CT can do complete multiple coronary artery (CT angiography) imaging in 10 seconds, as an outpatient procedure, almost as fast as a chest X-ray. An amazing non-invasive, patient-friendly, test, indeed! Will CT angiography replace coronary angiography and make cardiac catheterization and many other procedures obsolete? Time will tell.
And how about the arteries to the brain?
Yes, these too. Carotid arteries can be scanned for blockages (cholesterol plaques) to make an early diagnosis to prevent stroke. And all these in 3-dimensional images, which even lay people can read and understand. There are also other indications and uses, like a "virtual CT colonoscopy," instead of the conventional technique of inserting a fiberoptic scope (size of a ballpoint pen) into the anus and rectum to visualize the large intestine. The 64-slice CT can check any organ in the body, at lightning speed, sans the discomfort.
What impact does it have for treatment in general?
This is the area where this innovative technology really benefits patients. Besides allowing rapid and early diagnosis, and in a painless manner at that, the 64-slice CT will obviously save lives, not only in cardiovascular cases but among patients with cancer. Early detection in any malignancy increases the chances of survival and cure. This scanner also allows the physician to "look at the dynamic process" in cardiovascular conditions, and in cancer patients, for monitoring the changes in tumor sizes and response to treatment, aiding in prognostication. Nearly 60% of CT scans are done for cancer. In trauma, this new technology is a must, and a heaven-sent. This will also help reduce mortality rate among emergency room patients.
Does the 64-slice scanner have any limitation?
Yes, the scanner table cannot support more than 450 pounds, so it may not accommodate morbidly obese patients. The other is the price. The 64-slice scanner costs between $1.5 million to $2 million. As for the radiation exposure, some experts say the exposure during scanning with the 64-slice is like radiation from a day in the sun. Others think it's more than that. Nonetheless, the risk-benefit ratio tilts a lot towards the positive.