Fig. 5From: An additional challenge for head and neck radiologists: anatomic variants posing a surgical risk – a pictorial reviewAnatomic variants of the ethmoid roof. CBCT (a) shows clear asymmetry, the slope of the right vertical lamella (arrow) being more pronounced than on the contralateral side. b MDCT shows a deep olfactory fossa (type III according to the Keros classification)Back to article page