Iannetti classification of orbital invasion
The Iannetti classification grades orbital invasion by ethmoido-orbital tumors, such as adenocarcinoma, squamous cell carcinoma, adenoid cystic carcinoma, undifferentiated carcinoma, sarcoma, or olfactory neuroblastoma.
- grade I: erosion or destruction of the orbital medial wall
- grade II: extraconal invasion of the periorbital fat tissue
grade III: invasion of the medial rectus muscle, optic nerve, ocular bulb, or skin overlying the eyelid