Sonographic assessment of acute changes in plaque size and echogenicity and in intima-media thickness of carotid arteries after neck radiation therapy.

Background: Ultrasonic assessment of acute changes in carotid artery walls before and after neck radiation therapy (RT).

Methods: Fifty cancer patients scheduled for curative neck irradiation were included and underwent sonographic examination of carotid arteries, with assessment of intima-media thickness (IMT) and plaque size and echogenicity before and immediately after completion of RT.

Results: IMT was linearly correlated with age and before RT (r = 0.267, p = 0.007) and increased after RT (0.68 ± 0.11 versus 0.87 ± 0.16, p < 0.001), without correlation with total RT dose and protocol. New plaques (six hypoechoic, one hyperechoic, and one calcified) were found in eight patients after RT, while 17 of the 44 plaques that were present before RT increased in size, and 8 soft and 1 dense plaques in nine patients became calcified.

Conclusions: Radiation in the acute phase not only increases the IMT but also causes new plaque formation and changes in plaque size and echogenicity.