Imaging features and regional spread of malignant lacrimal sac and nasolacrimal duct tumors

Features	No. of Patients
Tumor location along lacrimal system on CT and MRI (n = 18)
Lacrimal sac only	3
Nasolacrimal duct only	0
Involving lacrimal sac and nasolacrimal duct	15
Tumor involvement of the nasolacrimal duct bony canal on CT (n = 16)
No duct dilation	2
Smoothly expanded duct	11
Erosive/lytic changes to duct	2
Iatrogenic changes to duct from prior dacryocystorhinostomy	1
Orbit involvement by tumor (n = 18)
Medial cantus/extraconal space of orbit	16
Intraconal space of orbit	2
Sinonasal involvement by tumor in primary malignant tumors of the lacrimal sac or duct (n = 5)a
Ethmoid sinus	4
Maxillary sinus	3
Nasal cavity	5
Other findings (n = 18)
Nodal metastasis	1
Distant metastasis	0
Perineural tumor spread along the infraorbital nerve	0
Intracranial extension	0
Dacryocystocele formation	0

^aPlease note that some patients had >1 subsite of sinonasal tumor extension.