Patients in Hong Kong can now have the service of the latest and fastest CT (Computed Tomography) scanner in Asia - Dual Source CT Scanner.

Introduced by the Hong Kong Sanatorium and Hospital in September, CT is a medical imaging method in which a three-dimensional image of a body structure is generated from a series of two-dimensional X-ray images taken around an axis.

The Dual Source CT Scanner was more convenient for patients and could be applied to more patients than previous models - single source CT scanners, according to Gladys Lo Goh, head of the hospital's Department of Diagnostic Radiology.

The new scanner is a major breakthrough since it could be used on patients with high or irregular heart rates, she said.

Single source CT scanners have certain limitations on patients, she said. For example, patients' heart rates have to be stable at 65 beat per minute below for imaging.

With the introduction of Dual Source CT Scanner, now patients do not need to take betablockers any more.

It is because the new scanner uses two X-ray sources and two detectors simultaneously. It works twice faster than single source CT scanners and could greatly save patients' time, she explained.

Another big benefit for patients is that the scanner could lower half of radiation exposure level than previous models, she said.

Due to its high speed of up to 160 kW power, the scanner could record full cardiac detail at half the dose necessary for excellent cardiac imaging.

The scanner also works well for obese patients, she said. For single source CT scanners, the highest radiation frequency had to be chosen for obese patients because of the large size of the body.

With dual source, there was an increased chance to take care of obese patients, she said.

Dual Source CT Scanner could also help understanding patients' health status in health tests, said Kwong Kwok-hay, assistant medical superintendent of the hospital.

Kwong said the process of the test only took several minutes. More than 100 patients had used the service at their hospital since the introduction, he said.

He, however, said the Dual Source CT Scanner was not suitable for the patients who are sensitive to dye and who have kidney problems.