The study of the effect on the image quality in low-dose CT of the paranasal sinuses
- VernacularTitle:鼻窦低剂量CT扫描对图像质量影响的研究
- Author:
Yangyang ZHOU
;
Ping HAN
- Publication Type:Journal Article
- Keywords:
Paranasal sinus diseases;
Dose-response relationship, radiation;
Tomography,X-ray computed
- From:
Chinese Journal of Radiology
2001;0(03):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To determine the effect of reducing mA on the diagnostic quality of images and the radiation dose to the lens in patients undergoing paranasal sinus CT. Methods Fifty patients undergoing paranasal sinus CT at 200 mA or 50 mA. The lens dose was measured using thermoluminescent dosemeters [LiF(Mg?Cu?P)]. Image quality was evaluated for six anatomical structures, including middle turbinate, uncinate process, maxillary ostium, ethmoid infundibulum, frontal recess, and cribriform plate. These anatomical structures were assessed as: not seen (0 points), demonstrated but not clearly visualized (1 points), or clearly demonstrated (2 points). Results Mean radiation dose to the lens was significantly reduced from 7.339 mGy (200 mA) to 1.108 mGy (50 mA). No significant difference of image quality between the two mA protocols was found in either rhinosinusitis group or non-rhinosinusitis group. And for rhinosinusitis the image quality showed no significant difference between high-resolution arithmetic and soft arithmetic. Conclusion CT scanning of the sinuses can be performed at greatly reduced mA without loss of diagnostic quality of the images. As far as the rhinosinusitis is concerned, high-resolution arithmetic can not improve the image quality and soft arithmetic is enough.
