Tear Drainage through the Upper Can,liculus in Case of Lower Canalicular ObstruCtion

Symptomatic epiphora has been rarely observed in patients jwith only one canaliculus obstruction. The authors experienced 7 cases of only lower canahculus obstruction without epiphora. Tear drainge of these eyes was assessed using dacryoscintigraphy and compared with the comtrol eyes. The measurement of T1/2 valuse, the duration of which a given amount of 99m-Tc-phytate drops to half in the conjunctival fornix was performed. The T1/2 valuse was 368.1 seconds in average in the eye with the lower canaliculus obstruction and 263.3 seconds in the control eyes(p