The site of origin and expansive routes of juvenile nasopharyngeal angiofibroma (JNA).

OBJECTIVE

Juvenile nasopharyngeal angiofibroma (JNA) is a rare vascular tumor of the nasopharynx occurring in young males. The aim of this study was attempt to find out the site of origin and the common expansion routes of JNA.

METHODS

The CT examinations of 46 untreated patients with histologically proven JNA were retrospectively analyzed. Evidence of tumor spreading of the locations are those following CT characteristics: (a) expansion and/or erosion of bony wall; (b) obliteration of normal fatty planes. In addition, three dimensional reconstruction technology was used to make further study.

RESULTS

The pterygoid canal was affected in all untreated cases and therefore was considered as the origin of JNA. Nineteen patients' tumors (41.3%) originated from the front part of pterygoid canal and the other 27 ones (58.7%) from the post part of pterygoid canal. Pterygoid canal, choanae and nasal cavity are the three most common sites of JNA.

CONCLUSION

The possible site of origin is pterygoid canal. After originating from this point, the tumor will invade sphenopalatine foramen, sphenoid sinus and pterygopalatine fossa first, and then into adjacent structure through aforementioned three sites.