Quantitative study of the effect of dacryocystorhinostomy on lacrimal drainage.

Using scintigraphy, we have studied the lacrimal drainage from the conjunctival sac of normal subjects and patients who have undergone dacryocystorhinostomy. A mathematical model of drainage was constructed that accurately described the complete activity curves for both groups. The initial rate of drainage was shown to be a relevant parameter to characterize drainage, and it was found to be different from normals to patients, indicating that the lacrimal pump mechanism is affected by dacryocystorhinostomy.