J Neurosurg. 2018 Sep 14;131(3):920-930. doi: 10.3171/2018.4.JNS172935. Print 2019 Sep 1.
Surgical treatment of pathological processes involving the ventral craniocervical junction (CCJ) traditionally involves anterior and posterolateral skull base approaches. In cases of bilateral extension, when lesions extend beyond the midline to the contralateral side, a unilateral corridor may result in suboptimal resection. In these cases, the lateral extent of the tumor will prevent extirpation of the lesion via anterior surgical approaches. The authors describe a unilateral operative corridor developed along an extreme lateral trajectory to the anterior aspect of the clival and upper cervical dura, allowing exposure and resection of tumor on the contralateral side. This approach is used when the disease involves the bone structures inherent to stability at the anterior CCJ.
To achieve exposure of the ventral CCJ, an extreme lateral transcondylar transodontoid (ELTO) approach was performed with transposition of the ipsilateral vertebral artery, followed by drilling of the C1 anterior arch. Resection of the odontoid process allowed access to the contralateral component of lesions across the midline to the region of the extracranial contralateral vertebral artery, maximizing resection.
Exposure and details of the surgical procedure were derived from anatomical cadavers. At the completion of cadaveric dissection, morphometric measurements of the relevant anatomical landmarks were obtained. Illustrative case examples for approaching ventral CCJ chordomas via the ELTO approach are presented.
The ELTO approach provides a safe and direct surgical corridor to treat complex lesions at the ventral CCJ with bilateral extension through a single operative corridor. This approach can be combined with other lateral approaches or posterior infratemporal approaches to remove more extensive lesions involving the rostral clivus, jugular foramen, and temporal bone.
传统上，涉及颅颈交界区（CCJ）腹侧的病理过程的手术治疗需要采用前颅底和颅底外侧入路。在双侧延伸的情况下，如果病变延伸超过中线到对侧，则单侧通道可能导致切除不彻底。在这些情况下，肿瘤的外侧范围将阻止通过前路手术方法切除病变。作者描述了一种单侧手术通道，该通道沿着极外侧轨迹延伸到斜坡和上颈椎硬脑膜的前侧，允许暴露和切除对侧的肿瘤。当疾病涉及到前 CCJ 稳定性所必需的骨结构时，使用这种方法。
为了暴露 CCJ 的腹侧，采用极外侧经髁突经齿突（ELTO）入路，同侧椎动脉移位，然后钻 C1 前弓。切除齿状突可进入中线对侧的病变，到达颅外对侧椎动脉区域，最大限度地切除肿瘤。
手术过程的暴露和细节来自解剖尸体。在完成尸体解剖后，获得了相关解剖标志的形态测量值。通过 ELTO 入路接近腹侧 CCJ 脊索瘤的病例示例得到了展示。
ELTO 入路为治疗双侧延伸的 CCJ 腹侧复杂病变提供了一个安全、直接的手术通道，通过单一手术通道即可完成。该方法可以与其他外侧入路或后路颞下窝入路联合使用，以切除涉及颅前斜坡、颈静脉孔和颞骨的更广泛病变。
