Zouaoui A, Maillard J C, Ganthier V, Chedid G, Dangeard S
Département de Neuroradiologie, Groupe hospitalier Pitié-Salpêtrière, Paris.
J Neuroradiol. 1995 Jun;22(2):86-102.
Cerebral venous angiomas are vascular malformations of the brain which, before the advent of modern imaging, and in particular MRI, were thought to be rare. They have a specific angiographic aspect called "caput Meduse" as it corresponds to the description of a large draining vein to which converge numerous radial veins located in the white matter. These true vascular malformations have characteristic histological features making it possible to differentiate them from other vascular malformations, notably cavernomas. These lesions are less scanty than classically believed, being the most frequent malformations encountered in post-mortem examination series. The circumstances in which cerebral venous angiomas are discovered vary considerably, and haemorrhage can be the revealing sign. Some authors regard these malformations as "abnormalities" of white matter veins and not as pathological entities, since they derive from a change in development during embryogenesis, but this theory is not supported by any anatomical evidence. The same authors attribute the bleeding to an associated cavernoma. Whereas CT enables venous angiomas and possible associated cavernomas to be detected, only repeated MRI explorations performed after the finding of venous angioma and hemorrhage can permit, by analysis of signal changes, to confirm or invalidate the non-pathological theory of the venous malformation and its tendency to bleed. Apart from hemorrhages, since gadolinium is used MRI is the most reliable and least invasive means to diagnose angiomas and to detect associated occult angiographic malformations. For this reason, nowadays only hemorrhages require an angiography in search of an arteriovenous malformation demanding prompt treatment. Moreover, MRI makes it possible to detect angiographically occult malformations.
脑静脉血管瘤是脑部的血管畸形，在现代影像学尤其是磁共振成像（MRI）出现之前，人们认为其较为罕见。它们具有一种特殊的血管造影表现，称为“水母头”，因为它与一条粗大引流静脉的描述相符，众多位于白质的放射状静脉汇聚于此。这些真正的血管畸形具有特征性的组织学特征，使其能够与其他血管畸形，尤其是海绵状血管瘤相鉴别。这些病变并不像传统认为的那样稀少，是尸检系列中最常见的畸形。脑静脉血管瘤被发现的情况差异很大，出血可能是其首发症状。一些作者认为这些畸形是白质静脉的“异常”而非病理实体，因为它们源于胚胎发育过程中的发育变化，但这一理论没有任何解剖学证据支持。同样这些作者将出血归因于相关的海绵状血管瘤。虽然CT能够检测到静脉血管瘤及可能相关的海绵状血管瘤，但只有在发现静脉血管瘤和出血后进行多次MRI检查，通过分析信号变化，才能证实或否定静脉畸形的非病理理论及其出血倾向。除出血外，由于使用了钆，MRI是诊断血管瘤及检测相关隐匿性血管造影畸形最可靠且侵入性最小的方法。因此，如今只有出血时才需要进行血管造影以寻找需要及时治疗的动静脉畸形。此外，MRI能够检测出血管造影隐匿性畸形。
