Anatomy
The lacrimal drainage system consists of: (a) puncta, (b) canaliculi, (c) lacrimal sac, (d) nasolacrimal duct ( Fig. 3.1 ).
Causes of a watering eye
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Hypersecretion secondary to anterior segment disease such as dry eye or inflammation.
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Defective drainage secondary to: (a) malposition of lacrimal puncta, (b) obstruction along the drainage system, (c) lacrimal pump failure secondary to lower lid laxity or orbicularis muscle weakness.
Acquired obstruction
Primary punctal stenosis
Causes:
(a) idiopathic, (b) chronic marginal blepharitis, (c) herpetic (simplex, zoster) lid infection, (d) conjunctival cicatrization.
Diagnosis:
narrow inferior punctum in the absence of punctal malposition.
Treatment:
dilatation alone ( Fig. 3.2A ) rarely confers long-term improvement; surgical punctoplasty is usually necessary ( Fig. 3.2B ).
Secondary punctal stenosis
Diagnosis:
narrow inferior punctum associated with punctal eversion ( Fig. 3.3A ).
Treatment
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Retropunctal cautery: for pure punctal eversion.
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Medial conjunctivoplasty: for medial ectropion without lid laxity ( Fig. 3.3B )
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Wider lid positional abnormalities: see Chapter 2 .
Canalicular obstruction
Causes:
(a) congenital and (b) acquired (e.g. trauma, herpes simplex infection, drugs, irradiation, chronic dacryocystitis).
Diagnosis:
site of obstruction will usually be evident on lacrimal irrigation as a ‘soft stop’ ( Fig. 3.4A ).
Treatment
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Intubation: silicone stents for partial obstruction.
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Canaliculo-dacryocystorhinostomy (CDCR): for total individual canalicular obstruction when there is 6–8 mm of patent normal canaliculus between the punctum and the obstruction.
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Lester Jones tube insertion: when it is not possible to connect the functional canaliculus to the sac (see below).
Nasolacrimal duct obstruction
Causes:
(a) idiopathic age-related stenosis (most common), (b) trauma, (c) granulomatosis with polyangiitis, (d) nasopharyngeal tumours.
Diagnosis
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Lacrimal irrigation: ‘hard stop’, without passage of irrigated fluid (complete obstruction) ( Fig. 3.4B ), or sparse passage of fluid (partial obstruction).
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Other investigations: conventional dacryocystography, digital subtraction dacryocystography and nuclear lacrimal scintigraphy
Treatment
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Dacryocystorhinostomy (DCR): (see below).
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Other procedures: stent insertion or balloon dilatation, usually in partial obstruction.
Dacryolithiasis
Pathogenesis:
inflammatory obstruction with tear stagnation and lacrimal epithelial metaplasia.
Diagnosis:
(a) intermittent epiphora and recurrent dacryocystitis usually in late adulthood, (b) distended and firm lacrimal sac that may form a mucocoele.
Treatment:
DCR.
Congenital obstruction
Nasolacrimal duct obstruction
Pathogenesis:
delayed canalization of the lower end of the nasolacrimal duct, affecting at least 20% of neonates.
Diagnosis
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Presentation : constant or intermittent epiphora ( Fig. 3.5A ), stickiness and sometimes frank bacterial conjunctivitis.
