Abstract:
Olfactory dysfunction (OD) is one of the most common symptoms in COVID-19 patients and can impact patients\' lives significantly. The aim of this review was to investigate the multifaceted impact of COVID-19 on the olfactory system and to provide an overview of magnetic resonance (MRI) findings and neurocognitive disorders in patients with COVID-19-related OD. Extensive searches were conducted across PubMed, Scopus, and Google Scholar until 5 December 2023. The included articles were 12 observational studies and 1 case report that assess structural changes in olfactory structures, highlighted through MRI, and 10 studies correlating the loss of smell with neurocognitive disorders or mood disorders in COVID-19 patients. MRI findings consistently indicate volumetric abnormalities, altered signal intensity of olfactory bulbs (OBs), and anomalies in the olfactory cortex among COVID-19 patients with persistent OD. The correlation between OD and neurocognitive deficits reveals associations with cognitive impairment, memory deficits, and persistent depressive symptoms. Treatment approaches, including olfactory training and pharmacological interventions, are discussed, emphasizing the need for sustained therapeutic interventions. This review points out several limitations in the current literature while exploring the intricate effects of COVID-19 on OD and its connection to cognitive deficits and mood disorders. The lack of objective olfactory measurements in some studies and potential validity issues in self-reports emphasize the need for cautious interpretation. Our research highlights the critical need for extensive studies with larger samples, proper controls, and objective measurements to deepen our understanding of COVID-19\'s long-term effects on neurological and olfactory dysfunctions.
摘要:
嗅觉功能障碍(OD)是COVID-19患者最常见的症状之一,可显著影响患者的生活。本综述的目的是调查COVID-19对嗅觉系统的多方面影响,并概述与COVID-19相关OD患者的磁共振(MRI)发现和神经认知障碍。在PubMed进行了广泛的搜索,Scopus,和谷歌学者,直到2023年12月5日。纳入的文章是12项观察性研究和1例病例报告,评估嗅觉结构的结构变化。通过MRI突出显示,和10项研究将嗅觉丧失与COVID-19患者的神经认知障碍或心境障碍相关联。MRI结果一致显示体积异常,嗅觉灯泡(OBs)的信号强度改变,持续OD的COVID-19患者的嗅觉皮层异常。OD和神经认知缺陷之间的相关性揭示了与认知障碍,记忆缺陷,和持续的抑郁症状。治疗方法,包括嗅觉训练和药物干预,讨论,强调持续治疗干预的必要性。这篇评论指出了当前文献中的一些局限性,同时探讨了COVID-19对OD的复杂影响及其与认知缺陷和情绪障碍的关系。一些研究中缺乏客观的嗅觉测量和自我报告中潜在的有效性问题强调了谨慎解释的必要性。我们的研究强调了对更大样本进行广泛研究的迫切需要,适当的控制,和客观测量,以加深我们对COVID-19对神经和嗅觉功能障碍的长期影响的理解。