Atresia of the Lacrimal Puncta or Canaliculi
Atresia of the lacrimal puncta or canaliculi refers to failure of canalization during development of the upper lacrimal system structures. Patients with atresia usually present with overflow of clear tears; there is no infection because bacteria cannot reach the lacrimal sac to produce one. The presence of mucopurulent discharge in a patient with atresia of either the upper or lower canaliculus usually indicates concomitant obstruction of the distal NLD, with reflux of discharge through the normal canaliculus.
There are 2 main causes of upper lacrimal system obstruction. One is a thin membrane that obstructs the lacrimal puncta, which are otherwise normal. Simple puncture of the membrane with a punctal dilator eliminates this obstruction. For concomitant obstruction of the distal NLD, probing of the distal system is necessary.
The second cause of upper lacrimal system obstruction is atresia of the puncta and canaliculi. In affected patients, no puncta can be seen (Fig 19-1). If only 1 of the canaliculi is atretic and there is mucopurulent discharge, probing of the distal duct through the patent canaliculus may be curative. If both the upper and the lower canaliculi are absent, an incision through the eyelid margin at the expected location of the canaliculi may reveal structures that can be cannulated. However, many patients ultimately require conjunctivodacryocystorhinostomy (CDCR), a procedure that creates a complete bypass of the lacrimal drainage system. CDCR is usually deferred until these patients are older. See BCSC Section 7, Oculofacial Plastic and Orbital Surgery, for a discussion of this procedure.
Figure 19-1 Atresia of the lacrimal puncta. No indentation is visible at the site of the normal punctal opening.
(Reproduced with permission from Lueder GT. Neonatal lacrimal system anomalies. Semin Ophthalmol. 1997;12(2):109.)
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.