Acquired Dacrocystocoele

80 year-old female with intermittent swelling at the right inner canthus for two years. Axial CT images show well-defined cystic lesion with mild dilatation of the proximal nasolacrimal duct (NLD) - arrow. Two-D reformatted images show continuity of the cyst with the NLD. No history of trauma or surgery.
Dacrocystocele: cystic dilatation of the nasolacrimal apparatus secondary to proximal or distal obstruction of the NLD. It may be congenital or acquired.
Congenital lesions should be differentiated from the more serious nasoorbital cephalocele.
Acquired lesions occur in adults with history of:
- Prior accidental trauma (e.g. LeFort 2 fracture),
- Previous NLD iatrogenic injury (e.g. Caldwell-Luc, uncinectomy),
- Post inflammatory or neoplastic stenosis.
Reference: Harnsberger, et al. Diagnostic Imaging: Head & Neck. 2004. Amirsys.
Credit: Dr Ahmed Haroun
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