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Background: Magnetic resonance imaging (MRI) has excellent spatial and soft tissue resolution in the periocular and orbital region, especially when combined with surface coil techniques. Other methods, including computed tomography, dacryocystography, and dacryoscintigraphy provide limited information in the area of the lacrimal drainage system. Magnetic resonance imaging was used in conjunction with other imaging modalities to compare the anatomic detail and clinically relevant information obtained about various pathologic processes in the lacrimal drainage area. Methods: Patients with a variety of lacrimal drainage disorders underwent MRI with either head or surface coils. Contrast agents also were used in selected cases. Seven case reports are presented. Results: Magnetic resonance imaging provided detailed information about local anatomy, extent of pathology, and, in some cases, etiology of the pathology. Conclusions: Magnetic resonance imaging with surface coils provides detailed soft tissue information when compared with dacryocystography and computed tomography in the area of the lacrimal drainage system. In selected cases of lacrimal drainage system pathology, MRI may provide data that affect patient management.

To document the change in drainage of tears that occurs with blinking, the authors evaluated 17 lacrimal systems of 12 individuals with dacryoscintigraphy. A significant difference in tear drainage was found by keeping the eyelids closed during the first 2 minutes after drop placement (P less than 0.03), but not from 2 to 5 minutes (P greater than 0.4). Retardation of tear drainage after droplet placement can be achieved by simple eyelid closure for 2 minutes.

Studies evaluating the relative importance of the upper and lower canaliculi in tear drainage have been many and varied, and at times the application of the data to clinical situations is difficult. In order to evaluate the relative tear flow in the upper and lower canaliculi and to quantitatively evaluate the different tear flow rates by a physiologic method, we have studied 11 patients using partial canalicular obstructions and dacryoscintigraphy. The authors found no statistical difference in tear flow between the upper and lower canalicular systems. This information has clinical application when deciding whether to repair an isolated canalicular injury.