The picture shows two pieces of dacryoliths obtained from the lacrimal sac during external dacryocystorhinostomy (DCR). The patient, a 34 year-old woman complained of recurrent epiphora. The DCG showed the nasolacrimal duct was patient but the lacrimal sac was noted to be of small volume. There was no evidence of stones in the sac on the plain X-ray or the DCG. Dacryoliths are usually radio-opaque and can be easily  missed during endonasal DCR. 
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