Menstrual cycle dependency of parenchymal contrast medium enhancement seems to be of minor relevance for premenopausal women with use of oral contraceptives.

MRI is a fast and reliable alternative to preoperative CT in examining paranasal sinuses and offers a good visualization of mucosal changes. CT and MRI both give an unreliable representation of the ethmoidal complex.

Additionally to the AP and PP, a delayed phase should be performed when cirrhosis is present. Even though AP and DP depicted all HCC's in this study, the PP provides undispensable additional information, so that, in our opinion, a THCT should be given preference when HCC is suspected.