醋酸异戊酯刺激相关嗅觉诱发电位对先天性嗅觉缺失患者嗅觉功能的评价

Olfactory event-related potentials to isoamyl acetate in congenital anosmia

目的通过先天性嗅觉缺失患者事件相关嗅觉诱发电位（ＯＥＰ）及与临床嗅觉功能检查的研究，进一步探讨ＯＥＰ的起源。方法对９例先天性嗅觉缺失患者及９例性别年龄匹配的正常人进行了嗅觉功能的评价，包括ＯＥＰ测定、标准的嗅觉识别评分和对３种气味的嗅觉阈值检查：纯嗅觉刺激的苯乙醇（ＰＥＡ）、刺激嗅神经同时中等程度刺激三叉神经的醋酸异戊酯（ＩＡＡ）和强烈刺激三叉神经的氯乙酚（ＣＡＰ）。结果嗅觉识别评分两组之间差异有非常显著性意义（Ｐ＜０００１）；ＰＥＡ和ＩＡＡ刺激嗅觉阈值２组之间差异也有非常显著意义（Ｐ＜０００１），而对刺激三叉神经的ＣＡＰ２组之间差异无显著性意义。ＩＡＡ刺激ＯＥＰ在对照组可记录到重复性好而且稳定的波形，由Ｐ１、Ｎ１、Ｐ２和Ｎ２成分组成。患者组对ＩＡＡ刺激未记录到重复可信的诱发电位，主观上也无任何反应。２组对空气对照刺激均未记录到诱发电位。结论ＯＥＰ是评价嗅觉功能特异的。

Objective To investigate the olfactory origin of the eventrelated potential (OEP) by evaluating OEP and standardized psychophysical measures in patients with congenital anosmia. Methods Olfactory function was evaluated by OEP and standardized psychophysical measures including smell identification test and odor detection threshold tests for 3 chemosensory stimulants: phenylethyl alcohol (PEA), isoamyl acetate (IAA), and chloracetyl phenone (CAP) in 9 subjects with isolated congenital anosmia and 9 ageand gendermatched normosmic controls. Results There was a significant difference in the smell identification test score (P<0.001) and odor detection thresholds for PEA and IAA (P<0.001) between the anosmic and normosmic subjects. Detection thresholds for CAP, a trigeminal stimulant, did not differ between the 2 groups. In the control subjects, OEP to IAA was characterized by 4 reproducible components (P1, N1, P2 and N2). In the subjects with congenital anosmia, no reproducible evoked potential components were identified in response to IAA. No reproducible evoked potential components were seen in response to the air control stimulus in either the anosmic or normosmic groups. Conclusion These data suggest that OEP provide a specific and objective measure of olfactory function.