TOPICAL CONTRAST-ENHANCED CT AND MR DACRYOCYSTOGRAPHY - IMAGING THE LACRIMAL DRAINAGE APPARATUS OF HEALTHY-VOLUNTEERS

OBJECTIVE. The purpose of this study was to evaluate the feasibility o f administering topical contrast material during helical CT dacryocyst ography and topical saline solution during MR dacryocystography to rev eal the lacrimal drainage apparatus. SUBJECTS AND METHODS. Fourteen he althy volunteers underwent helical CT dacryocystography, MR dacryocyst ography, or both. Eight of the 14 subjects underwent both techniques; three subjects underwent MR dacryocystography, and three subjects unde rwent CT dacryocystography. Images were evaluated by two radiologists for degree of visualization of components of the lacrimal drainage app aratus. Each volunteer was questioned about the relative discomfort of contrast material and saline solution administration. RESULTS, The la crimal drainage system was seen on both CT dacryocystography and MR da cryocystography, CT dacryocystography allowed two-dimensional and thre e-dimensional reconstructions on which adjacent bone anatomy could be seen. The MR dacryocystography two-dimensional reconstructions and max imum intensity projections also showed the drainage apparatus. However , smaller drainage structures were more consistently seen on CT dacryo cystography than on MR dacryocystography. Saline solution was more com fortable than contrast material. CONCLUSION. CT dacryocystography and MR dacryocystography reproducibly and noninvasively revealed the lacri mal drainage apparatus and allowed a better physiologic examination th an cannulation dacryocystography, MR dacryocystography can be performe d without administration of ionizing radiation or contrast material, b ut this technique cannot show adjacent bone anatomy and less consisten tly showed the smaller drainage structures than CT dacryocystography.