鼻咽癌放疗后副鼻窦放射反应的CT变化规律

目的　分析鼻咽癌放疗后副鼻窦炎的 CT表现 ,探讨其各个不同时期检查结果的变化规律。方法　14 5例鼻咽癌患者行γ射线放疗 75例 ,行 X射线放疗 70例 ,放疗前、后各个不同时期均行 CT检查。结果　上颌窦和蝶窦的放射反应可分为片状型、月牙型、环型和息肉型。筛窦放射反应以筛窦小房为单位 ,重者也可以多个小房融合成片状 ;筛窦的放射反应在放疗后 3个月内即可出现 ,上颌窦常在 3个月以后出现放射反应 ,而蝶窦一般在放疗后 1年以后才出现 ;大多数病例副鼻窦放射反应在 1年以后难以自动吸收、消退 ;两种方法放疗剂量相同时所致副鼻窦放射反应无明显差别 ,但放疗剂量在 3182 GBq以上时所致副鼻窦放射反应较其它放疗剂量时明显增高。结论　 CT检查可为鼻咽癌放疗后副鼻窦炎的诊断和治疗提供重要依据 ,提高患者的生存质量。

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.