Normative Quantitative Values for Dacryoscintigraphy and the Effect of Lid Massage

Our objectives were to establish normative quantitative values for dacryoscintigraphy in an older population and to evaluate the effect of lid massage. Methods: We conducted a prospective study of 44 eyes of 22 participants aged between 54-90 y that had no symptoms of epiphora and no clinical tear film instability, lid abnormality, lacrimal system impairment, or patent lacrimal duct on syringing. Dacryoscintigraphy was performed and interpreted by a single nuclear medicine physician. The scan protocol involved instillation of ^99mTc-pertechnetate in each eye, with a 45-min scan performed with 1-min frames. Lid massage and a sinus clearing maneuver were then performed, followed by a further 45 min of scanning. Results: The mean age of the 22 participants was 71.9 y. Quantitative analysis by half-clearance time (HCT) demonstrated a median presac HCT of 25.5 ± 15.0 min and a whole-eye HCT of 40.0 ± 19.5 min. There was no association between age or sex and HCT. Qualitatively, 29 of 44 eyes (66%) appeared to have at least 1 region of delayed clearance, with improvement noted in 23 after lid massage (79%). Conclusion: We report the quantitative values for dacryoscintigraphy in an asymptomatic older population who had normal findings on lacrimal examination. A high rate of delay in radiotracer transit on qualitative examination suggesting a low specificity. The false-positive rate was significantly improved with the novel approach of adding lid massage, and the significance of this finding merits further research.