June 30, 2009 — While
screening for possible pulmonary emboli using pulmonary CT angiography, a new
study shows that radiologists can effectively lower the patient radiation dose
by approximately 44% and improve vascular enhancement without deterioration of
image quality, according to a study performed at Brigham and Women’s Hospital
and Harvard Medical School, Boston, MA.
of 400 patients believed to have a pulmonary embolism were evaluated using
pulmonary CT angiography. Two hundred patients were evaluated using the standard
peak kilovoltage setting of 130 or 120 kVp and the other 200 patients were
evaluated using a low peak kilovoltage setting of 110 or 100 kVp. “Results
showed that lowering the peak kilovoltage setting by 20-kVp lead to superior
vascular enhancement without deterioration of image quality—allowing us to
effectively reduce the patient radiation dose,” said Shin Matsuoka, MD, lead
author of the study.
become an essential tool for the diagnosis of pulmonary embolism. However
because of the high percentage of negative results, radiation exposure has
become an important issue. Our study shows that lowering the kilovoltage setting
may be an effective method of lowering the radiation dose for most patients,” he
“Lowering the kilovoltage setting is
something that could be easily incorporated into daily clinical practice because
there is no additional equipment needed and there are no extra costs,” said Dr.
— News release courtesy of The American
Roentgen Ray Society (ARRS)