脑干海绵状血管瘤影像学

目的：结合临床表现特点，对４８例有组织学结果的脑干海绵状血管瘤的影像学表现进行分析。方法：４８例依发作方式分为两种类型。一类表现为突然发作的颅神经及传导束症状，部分为反复类似发作；另一种为静止性发作。所有病人均进行了ＣＴ及ＭＲＩ检查。并通过手术得到病理证实。结果：所有病例ＣＴ及ＭＲＩ均表现出海绵状血管瘤的特点。在非增强ＣＴ扫描表现为等或稍高密度，在增强ＣＴ扫描，病灶表现为轻至中度强化，水肿及占位效应均不明显。ＭＲＩ扫描表现为高信号或混杂信号，代表不同时相的出血及胶质样变。部分病例可见典型的桑椹样或网络样结构。除１８例病灶位于延髓或中脑外，大多病灶位于桥脑。３例在梯度回波扫描可见多发病灶。有１例组织学可见海绵状血管瘤的血管腔内存在弹性纤维；４例可见引流静脉及供血动脉。结论：桥脑是脑干海绵状血管瘤最常见部位；影像学特别是ＭＲＩ表现与病程及病变构成有关；部分组织病理学具有与其它血管畸形重叠的特点。手术彻底切除病灶对防止复发非常重要。

CT and MRI studies on cavernous angiomas of the brainstem

Objective: The clinical, radiological and histopathological features of the brainstem cavernous angiomas are reviewed based on a analysis of forty eight cases. Methods: CT and MRI images and pathologically proven were done on all 48 cases. Results: CT and MRI studies revealed characteristic of cavernous angiomas in all patients. The lesions were isodense to moderately hyperdense on nonenhanced CT scan. Enhancement following contrast administration varies from minimal to striking. MRI scans showed a typical popcorn like lesion with a well delineated complex reticulated core of high or mixed signal intensities representing hemorrhage in different stages of evolution and gliosis or granulation. The lesions were mainly located in the pons in 30 cases while 18 were in the midbrain or medulla oblongata. Multiple lesions were seen in 3 patients. Growth of cavernous angiomas was demonstrated in 5 patients on sequential scaning in present series. One case described from pathological material contained a few scattered elastic fibers and 4 cases contained tortuous vessels feeding or draining veins, but the lesions were otherwise entirely consistent with a diagnosis of cavernous angioma what are typically discrete multi lobulated berry like lesions. Conclusion: The pons is the common brainstem sites of cavernous angioma. Imaging features are usually related to the intralesional presence of blood products surrounding gliosis and granulation. Histology heterogeneity overlaps with other vascular malformations. The complet resection is important.