Asymmetry of the height of the ethmoid roof in relationship to handedness.

The aim of this work was to study the handedness differences in the height of the right and left ethmoid roofs. Hand preference was assessed using the Edinburgh Handedness Inventory. The height of the right and left ethmoid roofs was measured with computerised tomography (CT). The incidence of persons who had a lower ethmoid roof on the right side was significantly greater among right-handers than among left-handers; the incidence of persons who had a lower ethmoid roof on the left side was significantly greater among left-handers than among right-handers; and right and left ethmoid roofs were equal in all ambidextrous subjects. The relationship between the asymmetric ethmoid roofs and handedness may result from the right or left embryonic craniofacial region being smaller in the right- or left-handed subjects. This is particularly important in the light of the high degree of variability in the ethmoid roof, and even between the right and left sides in a given individual. Preoperative awareness of a patient's unique sinus anatomy may help prevent iatrogenic injury to the surrounding vital structures during ethmoid sinus surgery (ESS).