Table 1.
The frequency and the sites of tumor invasion identified by magnetic resonance imaging in 229 patients with nasopharyngeal carcinoma (NPC)
| Anatomical site | No. of patients (%) |
|---|---|
| Skull base involvement | 162 (70.7) |
| Clivus | 140 (61.1) |
| Basis of sphenoid bone | 135 (59.0) |
| Petrous apex | 120 (52.4) |
| Pterygoid process | 114 (49.7) |
| Foramen lacerum | 91 (40.0) |
| Great wing of sphenoid bone | 59 (25.8) |
| Paranasal sinus | 45 (19.7) |
| Foramen ovale | 32 (13.9) |
| Pterygopalatine fossa | 30 (13.1) |
| Jugular foramen | 21 (9.7) |
| Hypoglossal canal | 15 (6.5) |
| External auditory canal | 6 (2.6) |
| Soft tissue involvement | 147 (64.2) |
| Parapharyngeal space | 114 (49.8) |
| Oropharynx | 27 (11.8) |
| Nasal cavity | 23 (10.4) |
| Prevertebral muscle | 21 (9.2) |
| Masticator space | 18 (7.9) |
| Intracranial invasion | 74 (32.3) |
| Cavernous sinus | 71 (31.0) |
| Retroclival space | 11 (4.8) |
| Orbital apex | 11 (4.8) |