Objective of the present study was to investigate the tolerant radiation dose of nasal mucosa by observing and analyzing patients who received intensity-modulated radiation therapy (IMRT). Patients with nasopharyngeal carcinoma (N = 66) were selected for this study. The modified saccharin assay, endoscopy test, magnetic resonance imaging, and sino-nasal outcome test-20 (SNOT-20) survey were performed for the patients before and at 0 (T0), 3 (T1), 6 (T2), and 12 (T3) months after radiotherapy. The threshold doses of IMRT before radiotherapy and at T0, T1, T2, and T3 were determined as, respectively, 37 Gy, 37 Gy, 39 Gy, and 37 Gy for the saccharin test; 38 Gy, 37 Gy, 40 Gy, and 38 Gy for the endoscopy test; and 39 Gy, 37 Gy, 39 Gy, and 39 Gy for the nasal-related symptom scoring test. The modified saccharin assay, endoscopy test, and SNOT-20 survey revealed that a low dose (< threshold dose) of IMRT was associated with higher mucocilia transport rate (MRT), better endoscopy test score, and improved SNOT-20 score. The patients who received IMRT at a dose less than the threshold had the least damaged nasal mucosa morphology, and functional impairment scores were highest at T1 of IMRT. We conclude that nasal mucosa showed the most serious damage within 3 months after IMRT. If the radiation dose can be controlled within the threshold, the nasal mucosa can recover in the following few months, but recovery will be difficult otherwise.

中文翻译：

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特定辐射剂量下强度调制放射治疗与放疗后鼻粘膜损伤的预后相关。

本研究的目的是通过观察和分析接受强度调制放射治疗（IMRT）的患者，研究鼻粘膜的耐受放射剂量。本研究选择了鼻咽癌患者（N = 66）。在0（T0），3（T1），6（T2）和0（T0）之前和0和0时对患者进行改良的糖精测定法，内窥镜检查，磁共振成像和鼻窦结果测试-20（SNOT-20）调查。放疗后12（T3）个月。糖精试验确定放疗前和T0，T1，T2和T3处IMRT的阈值剂量分别为37 Gy，37 Gy，39 Gy和37 Gy。用于内窥镜检查的38 Gy，37 Gy，40 Gy和38 Gy；和39 Gy，37 Gy，39 Gy和39 Gy用于鼻相关症状评分测试。改良的糖精测定，内窥镜检查，SNOT-20调查显示，低剂量（<阈值剂量）的IMRT与较高的粘液纤毛转运率（MRT），更好的内窥镜检查得分和SNOT-20得分有关。以小于阈值的剂量接受IMRT的患者鼻黏膜形态受损最少，在IMRT的T1时功能障碍评分最高。我们得出的结论是，IMRT后3个月内，鼻粘膜损伤最严重。如果可以将放射剂量控制在阈值之内，则鼻粘膜可以在接下来的几个月内恢复，但是否则很难恢复。以小于阈值的剂量接受IMRT的患者鼻黏膜形态受损最少，在IMRT的T1时功能障碍评分最高。我们得出的结论是，IMRT后3个月内，鼻粘膜损伤最严重。如果可以将放射剂量控制在阈值之内，则鼻粘膜可以在接下来的几个月内恢复，但是否则很难恢复。以小于阈值的剂量接受IMRT的患者鼻黏膜形态受损最少，在IMRT的T1时功能障碍评分最高。我们得出的结论是，IMRT后3个月内，鼻粘膜损伤最严重。如果可以将放射剂量控制在阈值之内，则鼻粘膜可在接下来的几个月内恢复，但否则恢复将很困难。