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 |
↵a Please note that some patients had >1 subsite of sinonasal tumor extension.