[Concrements of the lacrimal apparatus]

Concrements of the lacrimal apparatus, known as dacryoliths, can occur at different localizations and can cause a variety of symptoms. A common clinical sign is chronic inflammation, possibly exhibiting acute exacerbation. Based on a literature review and descriptive clinical cases with histopathological correlations, this contribution summarises the most important information concerning epidemiology, aetiopathogenesis, composition, histology, and therapy of lacrimal concrements. Furthermore, factors known to affect lacrimal lithogenesis are addressed. Concrements of the lacrimal gland cause a swelling at the lateral canthus. With only mild pain, this manifests as circumscribed conjunctival hyperaemia. Histologically, the gland tissue is characterised by acute-erosive to chronic inflammation. The concrements consist of amorphic material. Inflammatory infiltration is dominated by neutrophil granulocytes. Canalicular concrements are highly correlated with chronic canaliculitis. Besides epiphora, patients present with purulent discharge at the affected canaliculus. Actinomyces are frequently found inside these deposits and form drusen-like formations. The surrounding tissue reacts with plasma-cellular and granulocytic inflammation. Dacryoliths (concrements of the lacrimal sac) are associated with dacryocystitis, whereby acute and chronic types are common. Stones can be found in up to 18% of patients undergoing dacryocystorhinostomy or dacryoendoscopy. Preoperative diagnostic testing is challenging, as many lacrimal sac stones cannot be reliably visualised by diagnostic procedures. Recurring episodes of epiphora, mucopurulent discharge, and dacryocystitis are common indicators of dacryoliths. Lacrimal syringing is often possible and shows that total blockage is not present. Histology of the lacrimal mucosa reveals lymphocytic infiltration and submucosal fibrosis. The immediate vicinity of the dacryoliths shows acute inflammation. Therapy consists of stone extraction and improving lacrimal drainage, as the latter is recognised as the main risk factor for dacryolith formation.