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Transcanalicular Diode Laser-assisted Dacryocystorhinostomy for the Treatment of Primary Acquired Nasolacrimal Duct Obstruction
Published on: October 13, 2017
Effects of beta-adrenergic antagonist on width of nasolacrimal drainage system lumen
1Department of Ophthalmology, Ehime University School of Medicine, Shitsukawa, Toon City, Ehime, Japan. nariokaj@m2.dion.ne.jp
Aims:
The aims of this study were to determine the effect of a beta-adrenergic antagonist on the width of the nasolacrimal drainage system lumen.
Methods:
The asymptomatic sides of 18 patients (14 women and 4 men) with unilateral stenosis or obstruction of the nasolacrimal drainage system were studied. The tear meniscus height on the asymptomatic side was normal and the nasolacrimal drainage system was patent, as revealed by dacryocystography. The nasolacrimal drainage system on the asymptomatic side was infused with 100 microL of 0.5% timolol maleate, and dacryocystography was performed to determine the width of the lumen of the nasolacrimal drainage system.
Results:
Timolol reduced the width of the lumen significantly, and the changes were more marked in the nasolacrimal duct (NLD), especially the middle and lower regions. The width of the lacrimal sac was not significantly changed.
Conclusions:
The decrease in the width of the nasolacrimal drainage system lumen, especially the NLD, by a beta-adrenergic antagonist suggests that the drainage of tears through the NLD may be influenced, in part at least, by the autonomic nervous system.
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