Dacryocystography: comparison of water-soluble and oil-based contrast agents

Dacryocystography has been widely used in the assessment of the nasolacrimal duct system, particularly in patients with epiphora. Our study was undertaken to evaluate image quality and level of patient discomfort during examinations with water-soluble contrast agents (iohexol [Omnipaque 240], iopamidol [Isovue 200 and 300], and 52.7% diatrizoate meglumine and 26.9% iodipamide meglumine [Sinografin]) compared with the iodized oil-based contrast agent Lipiodol. Fifty-five dacryocystograms were obtained from 41 consecutive patients. The procedure was performed first with a water-soluble contrast agent, then repeated with Lipiodol. A distention technique was used with conventional radiography. Patients were asked to evaluate their level of discomfort (none, mild, moderate, severe). The images were evaluated separately by two radiologists, blinded to which water-soluble agent was employed, and the images were graded on a five-point scale. Images obtained with Lipiodol were significantly better than those with other agents (P less than .02), and image quality deteriorated as iodine concentration decreased. Use of Isovue 300 and Sinografin produced significantly more patient discomfort (P less than .03) than the use of other agents. The authors conclude that, in most instances, Lipiodol is the contrast agent of choice with regard to both highest level of patient comfort and greatest conventional radiographic image quality among the agents compared.