Estimate of radiation dose to the lens in balloon sinuplasty

Abstract

Objectives To estimate radiation dose to the lens during fluoroscopy-assisted balloon dilation of sinus ostia and to estimate the length of fluoroscopy time that will be tolerated. Methods Radiation dose to the lens per unit fluoroscopy time was extrapolated from published data in fluoroscopically-guided balloon dacrocystoplasty. Results Mean exposure varies from 0.041 (right eye) to 0.284 (left eye) mGy/sec ( P = 0.037) because the left eye is closer to the radiation source during the lateral projection. Threshold for lenticular opacity has been estimated as 500 mGy, which would be attained in the left eye after approximately 29 minutes of fluoroscopy. Conclusions The lens may tolerate <30 minutes of fluoroscopy during balloon sinuplasty. The left eye receives a potentially greater radiation dose because of its proximity to the source in the lateral projection. Dedicated studies are indicated to specifically examine this issue during balloon sinuplasty.