Department of Neurosurgery, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
Neurosurgery. 2011 Jan;68(1):E258-62. doi: 10.1227/NEU.0b013e3181ff355c.
Arachnoid cysts have not been reported to be located within the brain parenchyma. We present a case of an arachnoid cyst that was contained entirely within the right frontal lobe devoid of communication with the subarachnoid space and ventricle.
A 65-year-old woman presented with a 1-year history of progressive headache and nausea. Computed tomographic and magnetic resonance imagining scans showed a well-defined, nonenhancing mass measuring 5 × 5 × 3.5 cm in the right frontal lobe. The mass appeared to be contained entirely within the brain parenchyma. The patient underwent a right frontal craniotomy, at which time the cystic mass was identified in the brain parenchyma without any communication with the arachnoid space. The cyst contained a clear fluid, and its wall was excised. The fluid contents demonstrated a composition similar to that of normal cerebrospinal fluid. Histological and immunohistochemical examinations of the cyst wall were compatible with the diagnosis of an arachnoid cyst. Postoperatively, the symptoms of the patient resolved, and no recurrence was observed up to 6 months after removal.
The present case showed an intraparenchymal arachnoid cyst arising in the frontal lobe. Although the etiology is not known, an arachnoid cyst should be included in the differential diagnosis of primary intracerebral cysts.
蛛网膜囊肿尚未见有位于脑实质内的报道。我们报告一例蛛网膜囊肿完全位于右额叶内，与蛛网膜下腔和脑室均无交通。
一名 65 岁女性，表现为进行性头痛和恶心 1 年。计算机断层扫描和磁共振成像扫描显示右额叶内有一个界限清楚、无强化的肿块，大小为 5×5×3.5cm。该肿块似乎完全位于脑实质内。患者接受了右额开颅术，术中在脑实质内发现囊性肿块，与蛛网膜下腔无任何相通。囊肿内含有清亮液体，其囊壁被切除。囊液的成分与正常脑脊液相似。囊壁的组织学和免疫组织化学检查与蛛网膜囊肿的诊断相符。术后患者症状缓解，切除后 6 个月内未见复发。
本病例显示起源于额叶的脑实质内蛛网膜囊肿。尽管病因不明，但蛛网膜囊肿应包括在原发性脑内囊肿的鉴别诊断中。
