Differentiating bipolar disorder from unipolar depression is one of the most difficult clinical questions posed in pediatric psychiatric practices, as misdiagnosis can lead to severe repercussions for the affected child. This study aimed to examine the existing literature that investigates brain differences between bipolar and unipolar mood disorders in children directly, across all neuroimaging modalities. We performed a systematic literature search through PubMed, PsycINFO, Embase, and Medline databases with defined inclusion and exclusion criteria. Nine research studies were included in the systematic qualitative review, including three structural MRI studies, five functional MRI studies, and one MR spectroscopy study. Relevant variables were extracted and brain differences between bipolar and unipolar mood disorders in children as well as healthy controls were qualitatively analyzed. Across the nine studies, our review included 228 subjects diagnosed with bipolar disorder, 268 diagnosed with major depressive disorder, and 299 healthy controls. Six of the reviewed studies differentiated between bipolar and unipolar mood disorders. Differentiation was most commonly found in the anterior cingulate cortex (ACC), insula, and dorsal striatum (putamen and caudate) brain areas. Despite its importance, the current neuroimaging literature on this topic is scarce and presents minimal generalizability.

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区分青年双相情感障碍与单相抑郁症：神经影像学研究的系统文献综述

区分双相情感障碍与单相抑郁症是儿科精神病学实践中最困难的临床问题之一，因为误诊可能会对受影响的儿童造成严重影响。本研究旨在检查现有文献，这些文献直接通过所有神经影像学方式调查儿童双相和单相情绪障碍之间的大脑差异。我们通过 PubMed、PsycINFO、Embase 和 Medline 数据库进行了系统的文献搜索，并定义了纳入和排除标准。系统定性评价包括九项研究，包括三项结构 MRI 研究、五项功能 MRI 研究和一项 MR 波谱研究。提取相关变量并定性分析儿童双相和单相情绪障碍以及健康对照之间的大脑差异。在九项研究中，我们的审查包括 228 名被诊断患有双相情感障碍的受试者、268 名被诊断患有重度抑郁症的受试者和 299 名健康对照者。六项审查的研究区分了双相和单相情绪障碍。分化最常见于前扣带回皮层 (ACC)、脑岛和背侧纹状体（壳核和尾状核）大脑区域。尽管它很重要，但目前关于这个主题的神经影像文献很少，而且普遍性极低。268 名被诊断为重度抑郁症，299 名健康对照者。六项审查的研究区分了双相和单相情绪障碍。分化最常见于前扣带回皮层 (ACC)、脑岛和背侧纹状体（壳核和尾状核）大脑区域。尽管它很重要，但目前关于这个主题的神经影像文献很少，而且普遍性极低。268 名被诊断为重度抑郁症，299 名健康对照者。六项审查的研究区分了双相和单相情绪障碍。分化最常见于前扣带回皮层 (ACC)、脑岛和背侧纹状体（壳核和尾状核）大脑区域。尽管它很重要，但目前关于这个主题的神经影像文献很少，而且普遍性极低。