Punctal and Canalicular Agenesis and Dysgenesis
The medial eyelid margin is inspected for the presence of elevated lacrimal papillae and puncta. Close inspection may reveal a punctum with a membranous occlusion, which can usually be opened with a sharp probe. Temporary intubation (discussed in the subsection Congenital Nasolacrimal Duct Obstruction) or placement of a silicone plug may help prevent recurrence. If the punctum is truly absent, the surgeon may cut down through the eyelid margin medial to the expected punctum location to try to identify the canaliculus. Alternatively, retrograde probing through an open lacrimal sac with direct visualization of the common canalicular opening (common internal punctum) may identify the canaliculus. Occasionally, these maneuvers reveal a relatively mature canalicular system with a patent nasolacrimal sac and duct, in which case intubation may be performed. Symptomatic patients with a single punctum may require surgery to relieve NLDO rather than canalicular obstruction. Symptomatic patients with complete absence of the puncta and the canalicular system require a conjunctivodacryocystorhinostomy (CDCR). This is performed when the patient is old enough to allow proper care of the Jones tube. (CDCR is discussed in the section Canalicular Obstruction later in this chapter.)
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.