The lacrimal drainage apparatus are paired structures that commence from the medial end of the upper and lower eyelid margins as the lacrimal puncta at the mucocutaneous junction, course through the medial end of the eyelid and the anterior limbs of the medical canthal tendon as the upper and lower canaliculi, which in most individuals merge into a common lacrimal canaliculus. The common canaliculus enters the lacrimal sac at its lateral wall with the fundus above and the body below, which then courses along the medial wall of the maxilla to open into the inferior nasal meatus under the inferior turbinate at the valve of Hasner. In general, tumors arising from the upper lacrimal drainage system are uncommon and when occur are usually benign especially at the punctal orifices. Tumors of the lacrimal sac and the nasolacrimal duct are extremely rare and when suspected, all efforts should be ensured to rule out malignancy.
Pujari A, Ali MJ, Mulay K, et al. The black lacrimal sac: a clinicopathological correlation of malignant melanoma with anterior lacrimal crest infiltration. Int Ophthalmol. 2014;34:111–5.PubMedCrossRefGoogle Scholar