Clinical Values of the Lacrimal Scintigraphic Parameters in Diagnosis of Epiphora: Comparison to Dacryocystography

Background: Dacryoscintigraphy (LS) is widely known to be an effective modality in diagnosing abnormalities of the lacrimal system that cause epiphora (pathological overflow of tear). However, LS rarely serves beyond the simple diagnostic use for lacrimal duct obstruction.Aim of the Study: To study (A) ability of both dacryocystography (DC) and LS in the a) diagnosis of lacrimal drainage system (LDS) obstruction, b) level of obstruction and c) whether it is complete or partial. In addition, (B) study the clinical value of very simple quantitative parameters derived from LS studies in epiphora patients compared to normal volunteers.Patients and Methods: Seventy-one subjects divided as 22 healthy controls and 49 patients complaining of epiphora (unilateral 22) and (bilateral 27) were subjected to clinical examination, syringing, DC and LS (both qualitatively and quantitatively). Results: It has been found that time activity curve (TAC) could detect partial obstruction in 6 eyes (diagnosed as normal by LS visual assessment), and another 6 eyes as complete obstruction (partial obstruction by visual assessment). Quantitative parameters in the form of T 1/2 and Tmax values together with activity ratios could localize site of the obstruction accurately. It has been found that DC and LS matched to diagnose normal and abnormal LDS in 77.9% (p 0.05) but this matching was reduced to 58.3% (p=0.05) at localization of level of obstruction in such way that LS could detect the canalicular obstruction more than DC. In addition, LS showed better matching with the clinical findings of epiphora and its degrees.Conclusion: Interpretation of LS visually, semiquantitatively and quantitatively are best to diagnose LDS obstruction, detect degree and levels of obstruction which help much in the management of epiphora. Lacrimal scintigraphy is a simple and accurate method for assessment of epiphora.