Abstract
INTRODUCTION: Dacryocystoceles are cystic dilatations of the lacrimal sac and nasolacrimal duct (NLD) due to the outflow obstruction at the Rosenmuller valve and the Hasner valve. Dacryocystoceles are rare in adults. MATERIALS AND METHODS: A retrospective case report. CASE PRESENTATION: We describe the first case of an acquired dacryocystocele in a patient with bilateral congenital nasolacrimal duct obstruction (CNLDO). A 25-year-old treatment-naïve bilateral CNLDO male presented with a superolateral dystopia of the left globe, proptosis, and a non-tender cystic mass at the left medial canthal region for the past six months. Computed tomography (CT scan) revealed a cystic enlargement of the left lacrimal sac with a distended NLD forming a nasolacrimal duct mucocele. Bilaterally, external DCR was performed. Histopathology was consistent with chronic dacryocystitis. DISCUSSION: Dacryocystoceles are rare in adults. They are either idiopathic or secondary to dacryocystitis, trauma, or dacryocystorhinostomy (DCR) surgery. In this case, the long-standing NLD obstruction has caused distention of the NLD and the lacrimal sac, leading to chronic fibroinflammatory changes in the Rosenmuller valve. CONCLUSION: Chronic fibroinflammatory changes in adult patients with untreated congenital nasolacrimal duct obstruction can cause dacryocystocele formation.