Clinical Trial: Lacrimal Drainage Resistance Study
Study Status: Completed
Recruit Status: Completed
Study Type: Observational
Official Title: Lacrimal Drainage Resistance Study
Brief Summary:
Epiphora, or uncontrolled tearing of the eyes, represents a common presenting complaint of patients seen by ophthalmologists. Epiphora may be due to non-obstructive causes, such as tear hypersecretion or functional tear pump failure, or obstructive causes. Functional tear pump failure may result from malposition of the eyelids, such as an abnormal out-turning (ectropion) or in-turning (entropion) of the eyelid.
Currently methods to diagnose partial nasolacrimal duct obstruction are purely qualitative in nature. Our research goal is to quantitatively measure the pressure generated during conventional probing and irrigation (P&I), and to measure the resistance to irrigation of the nasolacrimal drainage system.
The investigators will measure the pressure generated during conventional P&I using a disposable in-line pressure transducer. In addition, the investigators will use a syringe pump to deliver a constant flow rate of saline through a nasolacrimal cannula and measure the steady state irrigation pressure using the in-line transducer and digital pressure monitor. Resistance can be directly calculated from the known flow rate and pressure measurements.
The investigators will compare both the pressure generated during P&I and the lacrimal drainage resistance between patients with lacrimal drainage obstruction and controls patients with no obstruction (functional tear pump failure) as determined by clinical exam.
Clinical applications for measuring lacrimal drainage resistance include quantifying partial nasolacrimal duct obstruction, guiding the choice of surgical procedure, and determining the success of lacrimal drainage procedures.
Detailed Summary:
Lacrimal Drainage Resistance
I. Introduction
This proposal describes our plan to study the resistance of the lacrimal drainage system during irrigation.
II. Research Aims
A. Specific Aims
- To quantitatively measure the resistance of the lacrimal drainage system during irrigation.
- To determine differences in lacrimal drainage resistance between patients with obstructed tear drainage systems and patients with functional tear pump failure.
- To measure the pressure generated during traditional probing and irrigation of the lacrimal drainage system.
B. Background and Significance
Epiphora, or uncontrolled tearing of the eyes, represents a common presenting complaint of patients seen by ophthalmologists. Epiphora may be due to non-obstructive causes, such as tear hypersecretion or functional tear pump failure, or obstructive causes. Functional tear pump failure may result from malposition of the eyelids, such as an abnormal out-turning (ectropion) or in-turning (entropion) of the eyelid.
Tears normally drain from the eye through two small holes, called puncta, one located in the upper eyelid and one in the lower eyelid, and then through two channels, called canaliculi, that empty into the lacrimal sac. Tears drain from the lacrimal sac through the bony nasolacrimal duct into the nasal cavity. Obstruction may occur at any level of the system, and may be partial or complete.[1] The focus of this study is acquired (as opposed to con
Sponsor: The Cleveland Clinic
Current Primary Outcome: Lacrimal drainage resistance [ Time Frame: one-time clinical measurement ]
Original Primary Outcome: Same as current
Current Secondary Outcome: Pressure generated during nasolacrimal duct irrigation [ Time Frame: one-time clinical measurement ]
Original Secondary Outcome: Same as current
Information By: The Cleveland Clinic
Dates:
Date Received: May 13, 2011
Date Started: April 2009
Date Completion:
Last Updated: February 17, 2015
Last Verified: February 2015
