網(wǎng)友正在提問
頸部血管瘤為先天性疾病,是血管在胚胎發(fā)育的過程中,使血管的某一階段發(fā)育障礙,使其形態(tài)停止在該階段。血管瘤是由大量增生的血管所構(gòu)成。胚胎早期,原始脈管是一種單純由內(nèi)皮細胞組成的管狀物,它們在間質(zhì)中間形成一個致密的網(wǎng)。以后隨著各器官的發(fā)育,原始脈管網(wǎng)逐漸分化成與器官聯(lián)系的許多血管叢和淋巴管叢。
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