This study describes a new approach to provide detailed quantification of the impact of surgical intervention on bilateral nasal airflow using voxel-based simulation. Computed tomography and magnetic resonance imaging scans were used to reconstruct 3D realistic models of both the pre- and post-operative nasal airways. Voxel-based simulation of quiet restful inspiratory flow was then performed using meshes of varying refinement to determine the level of mesh refinement required to adequately resolve the flow and heat transfer. For meshes with voxel pitches of 0.10 mm, the voxel model successfully simulated the overall pressure drop and airflow temperatures.