title: Quantitative lacrimal scintigraphy in the assessment of epiphora.
abstract: The transit of Tc-99m pertechnetate through 122 lacrimal drainage systems was quantified. Systems were categorized as having presac, preduct, intraduct, or no delay. Scintigraphy indicated an obstruction in 81.3% of eyes with epiphora. Of the 18 eyes in whom only scintigraphy revealed an obstruction, all 3 who underwent surgery experienced symptom relief. In patients presenting with unilateral epiphora the mean canthus half-time (12.9 vs. 7.2 minutes), time-to-peak activity at the sac (11.6 vs. 3.1 minute), and sac half-time (19.0 vs. 10.3 minutes) were significantly prolonged in the symptomatic eye. Similarly, the sac-to-canthus (0.32 vs. 0.72), duct-to-canthus (0.32 vs. 0.99), and duct-to-sac ratios (0.48 vs. 0.79) of peak activity were all significantly reduced in the symptomatic eye. When compared with "no delay," "presac," "preduct," and "intraduct" delay were significantly associated with attenuated clearance times or reduced ratios of peak activity corresponding to the level of obstruction. We conclude that there is a significant association between symptomatic epiphora and quantitative variables at the canthus and sac in lacrimal scintigraphy. Quantitative variables help locate the level of an obstruction.
authors.affiliation: Sydney Eye Hospital, Sydney, Australia.
authors.forename: James
authors.initials: J
authors.lastname: Jabbour
authors.forename: Hans
authors.initials: H
authors.lastname: Van der Wall
authors.forename: Lysandra
authors.initials: L
authors.lastname: Katelaris
authors.forename: Julian
authors.initials: J
authors.lastname: Leslie
authors.forename: Douglas
authors.initials: D
authors.lastname: Mackey
authors.forename: Raf
authors.initials: R
authors.lastname: Ghabrial
mesh_terms: D000465:Algorithms; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007765:Lacrimal Apparatus / Q000000981:diagnostic imaging*; D007766:Lacrimal Apparatus Diseases / Q000000981:diagnostic imaging*; D008297:Male; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013670:Sodium Pertechnetate Tc 99m
chemical_list: D019275:Radiopharmaceuticals; D013670:Sodium Pertechnetate Tc 99m