Australian and New Zealand Journal of Ophthalmology 1988; 16 281-290 SURGICAL MANAGEMENT OF THE LACRIMAL DRAINAGE SYSTEM ROSS BENGER FRACO, FRACS Sydney Prepared by request Abstract The physiology of normal tear drainage has been better defined in recent years Some of the refined tech nrques developed in the fields of anaesthesia and surgery have been applied to the lacrimal drainage system The combination of these advances has resulted in more rational and successful treatment of lacrimal drainage abnormalities A review of these advances is presented with a discussion on the treat ment of lacrimal drainage abnormalities Key words Canalicular disease, lacrrmal dramagesystem. nasolacrimal duct obstruction,punctal ma/ position. punctal stenosis In an era of major developments in ocular surgery, it is appropriate to review the advances made in the treatment of lacrimal drainage disorders. The physiology of lacrimal drainage has become better understood. This, combined with the use of modern anaesthetic and surgical techniques has produced refined management procedures with improved results. Many patients who attend ophthalmologists do so because of watery eyes and require assessment of the lacrimal secretory and drainage systems. An understanding of normal lacrimal drainage will provide for a rational approach to the assessment of the drainage system and its function, and then rational management of demonstrated abnor- malities. NORMAL LACRIMAL DRAINAGE Tears drain from the precorneal tear film along the eyelid margins to the upper and lower lacrimal puncta. The lacrimal puncta lie centrally within the lacrimal papillae and are open, pointing a little posteriorly into the tear film, while the eyes are open. The normal lacrimal punctum is only 0.3 mm in diameter although the canaliculus is wider, varying up to a maximum diameter of 2 mm in the ampulla of its vertical portion.’ In apposing upper and lower eyelids, the lacrimal papillae are the first areas to meet during the closing phase and the last to part during the opening phase. During eyelid closure, punctal closure occurs as a result of both the sphincter action within the individual puncta, and the apposition of the upper and lower lacrimal papillae which results from them rising and e~erting.’.~ The orbicularis oculi action during eyelid closure produces horizontal short- ening of the canaliculi, and so with the punctal orifices occluded, a positive pressure (up to 70 mm H,O) develops within the canaliculi. This intracanalicular pressure rises until it is sufficient to open the valve of Rosenmuller at the canalic- ular entry into the lacrimal sac.3 During the eyelid opening phase, the canaliculi lengthen and a negative pressure is generated within them. When the papillae separate and the puncta open, Reprint requests: Dr R. Benger, 250 Victoria Road. Drummoyne, New South Wales 2047, Australia. SURGICAL MANAGEMENT OF THE LACRIMAL DRAINAGE SYSTEM 28 1
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