Herrmann H D, Winkler D, Westphal M
Department of Neurosurgery, University Hamburg (UKE), Hamburg, Federal Republic of Germany.
Acta Neurochir (Wien). 1992;116(2-4):137-46. doi: 10.1007/BF01540866.
The evaluation of tumours located in the posterior part of the third ventricle or pineal region is achieved best by magnet resonance imaging (MRI). It shows the exact localization and extent, the involvement of neighbouring structures like thalamus or quadrigeminal plate and the displacement of the large veins, the internal cerebral veins, the vein of Galen and the veins of Rosenthal. If only CT is available, angiography should be performed prior to operation to identify the course of the veins. In children with a pineal region tumour the "tumour markers" AFP and beta-HCG should be determined before operation. We approach the rare tumours entirely located within the posterior part of the third ventricle by the posterior interhemispheric transcallosal route with the patient in prone position with the head elevated. The same approach is used for pineal region tumours extending above the internal cerebral veins. Tumours arising from the posterior thalamus extending into the thalamus and ventricle as well, are better approached by the posterior transcortical transventricular route since the lateral view is rather limited by the midline approach. The most frequent tumours in the pineal region are approached if they are located below the internal veins by the infratentorial, supracerebellar route in the sitting position. A total of 60 cases are evaluated. If AFP and/or beta-HCG are positive a highly malignant nongerminomatous germ-cell tumour must be suspected. We recommend initial chemotherapy with a combination of Vinblastine, Ifosfamide and Cis-platin without biopsy to avoid tumour seeding. After the "markers" are normalized operative removal of the residual tumour and radiotherapy should be carried out. In a series of 13 children operated on for pineal region tumours a rigid neuropsychological and endocrine evaluation was performed with encouraging results. During the last 10 years we have performed 49 open operations and 11 stereotactic biopsies. 40% of the patients were children under the age of 18. 40% of the tumours in childhood and 60% in adults were benign. In childhood 24% were germinomas and 20% non-germinomatous germ cell tumours.
位于第三脑室后部或松果体区的肿瘤，最佳评估方法是磁共振成像（MRI）。它能显示肿瘤的确切位置和范围、丘脑或四叠体板等邻近结构的受累情况以及大脑大静脉、大脑内静脉、大脑大静脉和罗森塔尔静脉的移位情况。如果只有CT可用，术前应进行血管造影以确定静脉走行。对于松果体区肿瘤患儿，术前应测定“肿瘤标志物”甲胎蛋白（AFP）和β-人绒毛膜促性腺激素（β-HCG）。对于完全位于第三脑室后部的罕见肿瘤，我们采用后半球间经胼胝体入路，患者俯卧位，头部抬高。对于延伸至大脑内静脉上方的松果体区肿瘤，也采用相同的入路。起源于丘脑后部并延伸至丘脑和脑室的肿瘤，采用后经皮质经脑室入路更好，因为中线入路的侧方视野相当有限。如果松果体区最常见的肿瘤位于大脑内静脉下方，则采用坐位经幕下小脑上入路。共评估了60例病例。如果AFP和/或β-HCG呈阳性，则必须怀疑为高度恶性的非生殖细胞瘤性生殖细胞肿瘤。我们建议在不进行活检的情况下，先用长春碱、异环磷酰胺和顺铂联合进行初始化疗，以避免肿瘤播散。在“标志物”恢复正常后，应进行残留肿瘤的手术切除和放疗。在一组13例接受松果体区肿瘤手术的儿童中，进行了严格的神经心理学和内分泌评估，结果令人鼓舞。在过去10年中，我们进行了49例开放手术和11例立体定向活检。40%的患者为18岁以下儿童。儿童期40%的肿瘤和成人期60%的肿瘤为良性。儿童期24%为生殖细胞瘤，20%为非生殖细胞瘤性生殖细胞肿瘤。
