Normally, there are three pairs of nasal turbinates in the nasal cavity. Co
ronal computed tomographies of 253 cases of sinusitis were examined for the
presence of additional turbinates and bilateral secondary middle turbinate
s were detected in two cases. Also, we describe another accessory turbinate
, 'bifid inferior turbinate', in one of these cases. Existence of these acc
essory turbinates may occur during embryologic development of lateral nasal
wall. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.