A SingHealth team has found a way to reduce radiation in CT brain scans, making it safer for patients

Medical scans such as x-rays and computerised tomography (CT) scans, which are used for injury, illness or regular medical check-ups, bring with them exposure to radiation. Although the radiation dosage from these is minimal, there is a very small risk of accumulated radiation in the body, which could increase the risk of cancer and birth defects.

Now, a team from the ​​National Neuroscience Institute (NNI) has upped the ante and found a way to further reduce radiation doses of CT scans to improve patient safety.

“Within any radiology department, the aim is always to use the lowest dose of radiation without compromising the quality of the image. So the project was a natural choice in our Quality Improvement initiative,” said team leader Dr Yu Wai-Yung, Senior Consultant, Department of Neuroradiology, National Neuroscience Institute (NNI), a member of the SingHealth​ group.

The institute scans close to 1,000 patients a month. Of these, the most frequently performed types of imaging are CT scans of the brain, cranial CT angiograms that show whether a blood vessel in the brain is blocked, and CT brain perfusions that assess the areas of the brain which are not getting adequate blood supply.

“Since they represent a large proportion of the scans we do, we decided to focus on the above for the project. We also decided on a two-pronged approach to reduce radiation doses,” said team member, Mr Ho Thye Sin, Principal Radiographer, CT-in charge, Department of Neuroradiology, National Neuroscience Institute (NNI), a member of the SingHealth group.

Radiation dose was reduced for safer CT scans

One was the use of the Adaptive Iterative Dose Reduction 3D (AID R), a new software that optimises reconstructed images. And the other was to lower the tube current.

A panel of six consultant neuroradiologists then evaluated the diagnostic quality of the resulting images by comparing them to images taken before the project. Based on feedback from the panel, adjustments to the settings were made along the way.

The project took about nine months to complete and involved more than 1,000 patients. In the end, the team’s efforts paid off. The effective radiation dose was reduced by 28 per cent for CT brain scans, 12 per cent for cranial CT angiograms and 30 per cent for CT brain perfusion. Image quality was also not compromised in the process.

The institute has since adopted the new lower levels of radiation, and has been successfully using them for the three types of scans since the project ended in September 2012. “What we showed with this project is that reducing the levels of radiation can be done, and done rather simply and easily,” said Dr Yu.

The success of the team could extend to other departments as well. The newly established parameters can easily be implemented in other departments using similar software. “At the end of the day, it’s all about improving patient safety and the quality of their health care,” said Dr Yu. “We are very happy that what we have done has contributed to both.”

Ref: Q15