Kawashima Masatou, Matsushima Toshio, Nakahara Yukiko, Takase Yukinori, Masuoka Jun, Ohata Kenji
Department of Neurosurgery, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan.
Neurosurg Rev. 2009 Oct;32(4):457-64. doi: 10.1007/s10143-009-0211-7. Epub 2009 Jul 17.
The trans-cerebellomedullary fissure (CMF) approach provides good exposure of the fourth ventricle without splitting the inferior vermis. The popularly utilized trans-CMF approach is performed in the midline suboccipital approach. However, the trans-CMF approach actually has two routes: medial and lateral. The lateral route is the trans-CMF approach through a lateral foramen magnum approach such as the transcondylar approach, opening the CMF from the lower unilateral side. We studied the surgical anatomy of the CMF and fourth ventricle. Based on the anatomic findings, we adopted the lateral route of the trans-CMF approach for four patients, each with a tumor near the jugular tubercle extending into the fourth ventricle through the CMF. Our study demonstrated that the lateral route of the trans-CMF approach enables sufficient exposure of not only unilateral cerebellopontine cistern but also of the lateral part of the fourth ventricle. A tumor is safely removed by this approach with easy feeder or tumor bed controls, especially if it is anchored at the lateral part of the CMF as is the jugular tubercle meningioma.
经小脑延髓裂（CMF）入路可在不切开小脑蚓部下份的情况下良好显露第四脑室。常用的经CMF入路是在枕下中线入路中进行。然而，经CMF入路实际上有两条路径：内侧和外侧。外侧路径是通过枕骨大孔外侧入路（如经髁入路）的经CMF入路，从下外侧方打开CMF。我们研究了CMF和第四脑室的手术解剖结构。基于解剖学发现，我们对4例患者采用了经CMF入路的外侧路径，每例患者的肿瘤位于颈静脉结节附近，通过CMF延伸至第四脑室。我们的研究表明，经CMF入路的外侧路径不仅能充分显露单侧桥小脑池，还能充分显露第四脑室的外侧部分。通过这种入路可以安全地切除肿瘤，并且易于控制供血血管或肿瘤床，特别是当肿瘤如颈静脉结节脑膜瘤一样附着于CMF外侧部分时。
