Radiation dose impacts on size of lung nodules seen on CT images

Research has shown how radiation dose can affect size of lung nodules observed on CT images.

The size of chest lymph nodes and lung nodules identified by CT images depends on the amount of radiation used for the examination.
That is according to new research from the Massachusetts General Hospital in Boston, which found lower radiation doses resulted in a more varied size of lesions seen on CT images.
The team used a 3D image processing tool to quantitatively measure the volume of lymph nodes and lung nodules.
Lymph node volumes were estimated at 30 per cent lower in five cases and ten per cent higher in 25 cases of low dose compared with higher dose images.
The study also found that the calculated volume of lung nodules was 46 per cent lower in nine cases and 34 per cent higher in ten cases on lower dose compared to higher dose images.
Lead author of the study, Dr Beth Vettiyil, said: "We think that increased image noise (graininess of the image) on the lower dose scans may have caused the lesion volumes to vary so significantly."
While the study might suggest radiologists can use these tools to supplement their measurements, Dr Vettiyil added the use of such software measurements without a clinical correlation might not be advisable yet.