弥散加权磁共振成像评价鼻咽癌患者调强放疗前、后唾液腺功能的变化

目的评价DWI检测调强放疗(IMRT)对鼻咽癌(NPC)患者唾液腺功能影响的临床价值。方法对23例NPC患者行IMRT,并于放疗前、后行唾液腺静息状态DWI和酸刺激条件下重复DWI。计算双侧腮腺及颌下腺ADC值,并进行统计学分析。结果放疗前,静息状态腮腺平均ADC值明显低于颌下腺(P<0.05),酸刺激后腮腺及颌下腺ADC值表现出先降后升的变化趋势,最小值、最大值与静息状态相比差异有统计学意义(P<0.05)。放疗后,静息态腮腺及颌下腺平均ADC值显著高于放疗前(P<0.05),酸刺激条件下失去先降后升的变化趋势。结论 MR DWI可无创观察腮腺及颌下腺功能,较好地评价放疗后患者腮腺和颌下腺功能的变化。

Changes of salivary gland function in nasopharyngeal carcinoma patients before and after intensity-modulated radiotherapy with MR DWI

Objective To observe the clinical value of DWI for investigating changes of salivary gland function in nasopharyngeal carcinoma (NPC) patients before and after intensity-modulated radiotherapy (IMRT). Methods DWI was performed in 23 NPC patients once at rest and then during salivary acid stimulation before and after IMRT. ADC for both parotid and submandibular glands were calculated. Results Before radiotherapy, the mean ADC value at rest was significantly lower in the parotid than in the submandibular glands (P<0.05). During the period of stimulation, ADC value of the salivary glands first showed decrease, followed by steady increase. Compared with at rest, the minimum and maximum ADC value were significantly different (P<0.05). After radiotherapy, ADC value of the salivary glands at rest were significantly higher than before (P<0.05). During the period of stimulation, the tendency of first decrease and then increase disappeared. Conclusion DWI can be used to noninvasively observe the function of major salivary glands, and to evaluate functional changes of salivary glands.