3D computed tomography-dacryocystography (3D CT-DCG) and the contrast agents: direct comparison of Lipiodol and...

To compare the performance of two contrast agents, barium sulfate and lipiodol, in the performance of 3D CT-DCG. A prospective interventional radiological study was performed on 15 lacrimal drainage systems of 14 patients who clinically presented with nasolacrimal duct obstructions. All patients underwent CT-DCG, traditionally first using lipiodol and a week later by barium sulfate. CT-DCG data was used to construct 3D models as per standard published protocols. A 3D software was used to calculate the volume (which reflects the filling ability of the dye) and the number of details (counted by the number of different faces creating the object) of the 3D CT-DCG of the studied lacrimal drainage systems. The analysis was performed in R, version 4.3.2. The overall mean volume of the dye (filling feature) in the 3D CTDCG reconstructed models of the lacrimal system following lipiodol injection was 55.2 mm³ vs. 244.2 mm³ with barium sulfate (p < 0.001). A minimum of 94% gain was noted in volume with barium sulfate contrast (p < 0.001). The barium sulfate was superior to lipiodol for the same lacrimal drainage system and provided a better appreciation of lacrimal drainage details. The visualization of the stenosis and obstructions of the nasolacrimal duct were better delineated. The filling defects in cases of dacryoliths were more pronounced with barium sulfate with intricate visualization of the presumed shape and size of the dacryolith. The present study is the first to highlight the advantages of barium sulfate over the traditional contrast agent, lipiodol, for the acquisition of 3D CT-DCG images. Barium sulfate is a viable alternative and an economically more feasible option for performing 3D CT-DCG.