Introduction

The importance of an olfactory assessment of individuals with neurological diseases has attracted attention. Cerebrovascular disease is one of the most common diseases in Japan, but there are few reports on olfaction in patients with stroke. Herein we examined olfaction in patients with stroke.

Methods

We assessed 50 patients hospitalized for neurorehabilitation after stroke. For the assessment of olfaction, the dual tests known as the T&T olfactometry (T&T) test and the odor identification Open Essence (OE) test were administered. Since the OE test was introduced only recently in Japan, 100 healthy volunteers participated to provide OE data as the control group. We analyzed the patients’ T&T and OE data and the controls’ OE data, and we investigated the relationship between the olfaction data and the patients’ stroke-induced lesion areas.

Results

None of the patients reported experiencing inconvenience due to olfactory loss, although we classified 45 (90%) patients as hyposmic or anosmic based on their identification thresholds on the T&T test as well as their significantly low OE scores compared to the control data. However, the patients’ perception thresholds on the T&T test were in the normal range. Brain computed tomography examination data revealed that odor identification was not impaired in about half of the 23 patients with a putamen-thalamus lesion. In addition, our correlation analysis of each odorant in the OE test indicated that six of the 12 odorants are sufficient for olfactory assessments.

Conclusions

The results of the dual olfactory tests revealed that patients with stroke showed impaired odor identification but intact odor perception. It is possible that the direct pathway from the piriform cortex to the orbitofrontal cortex is essential for odor identification.

Implications

Because of their normal odor perception, most patients with stroke are not aware of their impaired odor identification. A set of six of the 12 odorants used in the OE test is capable of representing the total OE score, and its use will save time for olfactory tests in clinical assessments.

中文翻译：

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双重测试可揭示脑血管疾病患者的嗅觉识别受损

介绍

对神经系统疾病患者进行嗅觉评估的重要性引起了人们的关注。脑血管疾病是日本最常见的疾病之一，但有关中风患者嗅觉的报道却很少。在此，我们检查了中风患者的嗅觉。

方法

我们评估了 50 名因中风后住院接受神经康复治疗的患者。为了评估嗅觉，进行了称为 T&T 嗅觉测量 (T&T) 测试和气味识别 Open Essence (OE) 测试的双重测试。由于OE测试最近才在日本推出，因此有100名健康志愿者参与提供OE数据作为对照组。我们分析了患者的 T&T 和 OE 数据以及对照组的 OE 数据，并研究了嗅觉数据与患者中风诱发病变区域之间的关系。

结果

尽管我们根据 45 名 (90%) 患者在 T&T 测试中的识别阈值以及与对照数据相比明显较低的 OE 评分，将 45 名患者 (90%) 分类为嗅觉减退或嗅觉缺失，但没有患者报告因嗅觉丧失而感到不便。然而，患者在 T&T 测试中的感知阈值在正常范围内。大脑计算机断层扫描检查数据显示，在 23 名壳核丘脑病变患者中，约有一半的气味识别能力没有受到损害。此外，我们对 OE 测试中每种气味剂的相关分析表明，12 种气味剂中的 6 种足以进行嗅觉评估。

结论

双重嗅觉测试的结果显示，中风患者的气味识别能力受损，但气味感知完好。从梨状皮层到眶额皮层的直接通路可能对于气味识别至关重要。

影响

由于其正常的气味感知，大多数中风患者并没有意识到他们的气味识别能力受损。 OE 测试中使用的 12 种气味剂中的一组 6 种能够代表 OE 总分，其使用将节省临床评估中嗅觉测试的时间。