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Topical contrast-enhanced magnetic resonance dacryocystography.

PURPOSE
To evaluate the usefulness of magnetic resonance dacryocystography (MRD) with topical administration of normal saline solution and diluted Gd-DTPA solution for the assessment of lacrimal outflow disorders.


MATERIALS AND METHODS
Two T2-weighted sequences and two T1-weighted sequences were evaluated in this study. The 1:100 diluted Gd solution was prepared by diluting Gd-DTPA (Magnevist) with normal saline solution. A phantom study using tube phantoms of various diameters filled with normal saline solution and 1:100 diluted Gd solution was performed. A preliminary study was performed in ten normal volunteers. Eighteen patients with lacrimal outflow disorders underwent clinical MRD, and 14 also underwent conventional dacryocystography (CDG). MRD images were evaluated and compared with clinical symptoms and CDG images.


RESULTS
In all sequences, MRD could visualize the full length of 0.7 to 1.7 mm diameter tube phantoms and could show all of the normal lacrimal sacs and nasolacrimal ducts. In the clinical study, MRD findings were compatible with the symptoms in 14 patients but were not compatible with CDG findings in half of the cases.


CONCLUSION
Topical contrast-enhanced MRD provided a simple, non-invasive means of obtaining detailed morphological and functional information on the lacrimal drainage apparatus.