Congenital nasolacrimal duct obstruction: delineation of anatomic abnormalities with 3-dimensional reconstruction.

OBJECTIVE: To characterize anatomical abnormalities of the distal nasolacrimal duct (NLD) in children with congenital obstruction using high-resolution computed tomographic imaging.

METHODS: The anatomy of the bone and soft tissue of the NLD and the postductal anatomy of the inferior meatus in 6 children with a wide spectrum of NLD obstructions were imaged by computed tomographic scans and then reconstructed in a 3-dimensional viewer. Images were taken from prior axial (5 children) or coronal (1 child) computed tomographic facial scans at 0.625- or 1.25-mm mm resolution, respectively.

RESULTS: The axial computed tomographic images and 3-dimensional reconstructions showed bony obstructions of the distal NLD in 3 children, membranous obstructions of the distal NLD in 1 child, and a postductal obstruction in the inferior meatus in 1 child. One child had a combined soft tissue obstruction of the NLD and post-NLD obstruction.

CONCLUSIONS: This study provides anatomic evidence of a bony or membranous obstruction at the distal portion of the NLD or of a postductal obstruction at the inferior meatus in children with congenital NLD obstruction.