機能性振戦および本態性振戦におけるアルキメデス螺旋のループ
Aditya Murgai1, Gala Prado Miranda1, Guillermo Trocha Ramos1
1Department of Clinical Neurological Sciences, Western University, London, Ontario, Canada.
Tremor and other hyperkinetic movements (New York, N.Y.)
|December 22, 2025
まとめ
アルキメデス螺旋のループは、機能性振戦（FT）と本態性振戦（ET）の両方に現れます。高いループ数（≥7）はFTの診断に特異的ですが、感度は低く、臨床的文脈を補助します。
科学分野:
- 神経学; 運動障害
背景:
- 機能性振戦（FT）は、診断上の課題を伴う一般的な機能性運動障害です。; アルキメデス螺旋の描画は、振戦評価のためのベッドサイドツールです。; 「ストレッチシンキ」徴候（ループ）はFTで認められますが、FT対本態性振戦（ET）におけるその有病率は不明です。
研究 の 目的:
- FTおよびETにおけるアルキメデス螺旋のループの有病率を決定すること。; FTとETを区別するループ数の診断有用性を評価すること。
主な方法:
- 22人のFT患者および28人のET患者からのアルキメデス螺旋の後ろ向き分析。; 螺旋描画におけるループ数の定量化。; マン・ホイットニーのU検定およびROC分析を含む統計分析。
主要な成果:
- ループ（≥1）は、FT螺旋の45.5％およびET螺旋の60.7％に存在しました。; FTとETグループ間でループ数に有意差はありませんでした。; ループ数閾値≥7は、FTに対して高い特異度（0.96）を示しましたが、感度は低く（0.14）（PPV 0.75）。; ROC分析は、ループ数のみの低い識別能力を示すAUC 0.46を生成しました。
結論:
- アルキメデス螺旋のループは、FTとETの両方に発生します。; ループ数のみでは、FTとETを区別する能力は限られています。; ループ数≥7は、より広範な臨床評価におけるFTの特異的な、ただし感度の低い指標となる可能性があります。
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