[The regularity of changes on the CT images of accessory nasal cavity in patients with nasopharyngeal carcinoma after radiotherapy].

OBJECTIVE

To analyze the CT findings of nasal sinusitis in patients with nasopharyngeal carcinoma post-radiotherapy and detect the regularity of their change in different periods.

METHODS

This is a study on 145 cases of nasopharygeal carcinoma, including 75 cases treated by gamma-ray and 70 cases by X-ray. CT examinations on the patients were carried out pre-radiotherapy and post-radiotherapy in different periods.

RESULTS

The radioreactions in maxillary sinus and sphenoidal sinus might be classified as patch form, crescent form, ring form and polyform. The unit of radioreaction in ethmoidal sinus was ethmoidal cell. Several ethmoidal sinus cells were fused to patch in severe cases. The radioreactions in ethmoidal sinus, maxillary sinus and sphenoidal sinus were seen within three months, after three months and after one year respectively. And nasal sinus radioreactions of most cases were not absorbed spontaneously after one year. When the two kinds of radiotherapies were equal in dosing level, there was no obvious difference between them in respect to the radioreaction of accessory sinus, but when the dosing level was above 3182 GBq, the radioreaction of accessory sinus was remarkably increased, compared with those caused by lower-dose radiotherapies.

CONCLUSION

CT plays an important role in yielding helpful information for the diagnosis and treatment of the nasal sinusitis of nasopharyngeal carcinoma post-radiotherpy. The patients' life quality can be improved.