Research For Risk Factors And Mechanism Of Nasosinusitis After Radiotherapy Of Nasopharyngeal Carcinoma

Purpose:To evaluate the risk factors of nasosinusitis after radiotherapy of nasopharyngeal carcinoma(NPC); observe the growth condition of bacteria inside the nasal cavity and nasosinus; and observe the ultrastructure/microstructure of naso-cilia in patients who had suffered from nasosinusitis after radiotherapy. Primarily to learn the pathogenesis of nasosinusitis after radiation. Methods:1. From January 1990 to December 2001,153 NPC patients without nasosinusitis before radiotherapy were retrospectively analysed;2. 20 cases of nasosinusitis after radiation as trial group and 20cases of chronic sinusitis were selected as control group, compare with the bacteriological examination between two groups.3. To observe the nasal and paranasal mucosa in 10 patients with nasosinusitis after radiation by scanning electron microscope (SEM).Results:1. 66 patients had suffered from nasosinusitis after radiotherapy;2. There is a significant difference between trial group and control group in bacteriology examination.3. The mucociliary microstructure had destyoied even fall off inpatients with nasosinusitis after radiotherapy. Conclusion:The mechanism of nasosinusitis after radiation is cilia of mucosa inside nasal and paranasal was destroyed after irradiation; bacteria is not an important reason in nasosinusitis afer radiation and it cooperate with irradiation to aggravate sinusitis possibly; high T stage and nasal cavity infringement are the risk factors of nasosinusis after radiotherapy of nasopharyngeal carcinoma(NPC), on the other hand, nasopharyngeal cavity flush is the protect factor.