• Fifteen patients with symptoms of nasolacrimal duct obstruction were evaluated with B-scan and standardized A-scan ultrasonography. Results were correlated with findings on routine clinical tests of lacrimal drainage function, and echographic findings were confirmed at surgery in all cases. Ten normal lacrimal systems were also examined. In all patients the lacrimal sac and duct were easily visualized as an echolucent defect bounded by the bony lacrimal crests. Abnormal dilatation, diverticuli, and inflammatory exudates were readily detected. Surgically created dacryocystorhinostomy ostia were imaged on both A- and B-scans, as were obstructing membranes seen before surgical revision. Physiologic lacrimal pump failure could not be evaluated, and the exact site of obstruction could not be determined.
Dutton JJ. Standardized Echography in the Diagnosis of Lacrimal Drainage Dysfunction. Arch Ophthalmol. 1989;107(7):1010-1012. doi:10.1001/archopht.1989.01070020072032