目标:在神经外科病史中,脑干固有病变的治疗一直备受争议。脑干是中枢神经系统(CNS)的解剖结构,表现出最高浓度的细胞核和纤维,其简单的操作可以导致显著的发病率和死亡率。一旦确定了延髓的安全入口点之一,我们想评估治疗橄榄体的最安全方法(延髓前外侧表面最常用的安全进入区).所提出的目标是评估从远侧向和乙状后入路到橄榄体的每个表面的工作通道:距离,攻角和频道内容。
方法:要完成这项工作,总共使用了10个注射了红色/蓝色硅胶的头部。在使用的10个头部中总共进行了40个方法(乙状结肠后20个和远端外侧20个)。完成解剖学研究并获得所有方法的数据后,我们决定通过使用30名没有头颅或脑部病理的匿名患者的高清磁共振成像来扩大本研究的样本。使用的参考点与解剖学研究中定义的参考点相同。在定义了每个方法中的工作通道之后,工作距离,攻角,外露表面,并分析了中央轨迹中存在的神经血管结构的数量。
结果:从乙状窦后入路到橄榄体的颅骨和内侧区域的距离为52.71mm(SD3.59),从远外侧为27.94mm(SD3.99);到橄榄体的最基底区域,与乙状窦后入路的距离为49.93(SD3.72),与远外侧的距离为18.1mm(SD2.5)。乙状窦后入路与尾区的攻角为19.44°(SD1.3),远外侧入路与尾区的攻角为50.97°(SD8.01);乙状窦后入路与颅区的攻角为20.3°(SD1.22),远外侧为39.9°(SD5.12)。关于神经血管结构,发现动脉结构的可能性在外侧较远,而神经结构更有可能来自乙状窦后入路。
结论:作为这项工作的结论,我们可以说,远外侧入路为显微手术治疗通过橄榄体尾半部进入的内在延髓和延髓病变提供了更有利的条件。在这些情况下,球和桥-球病变通过橄榄体的颅骨半部接近,对于选定的病例,可以考虑乙状窦后入路。
Throughout neurosurgical history, the treatment of intrinsic lesions located in the brainstem has been subject of much controversy. The brainstem is the anatomical structure of the central nervous system (CNS) that presents the highest concentration of nuclei and fibers, and its simple manipulation can lead to significant morbidity and mortality. Once one of the safe entry points at the medulla oblongata has been established, we wanted to evaluate the safest approach to the olivary body (the most used safe entry zone on the anterolateral surface of the medulla oblongata). The proposed objective was to evaluate the working channel from the surface of each of the far lateral and
retrosigmoid approaches to the olivary body: distances, angles of attack and channel content.
To complete this work, a total of 10 heads injected with red/blue silicone were used. A total of 40 approaches were made in the 10 heads used (20
retrosigmoid and 20 far lateral). After completing the anatomical study and obtaining the data referring to all the approaches performed, it was decided to expand the sample of this research study by using 30 high-definition magnetic resonance imaging of anonymous patients without cranial or cerebral pathology. The reference points used were the same ones defined in the anatomical study. After defining the working channels in each of the approaches, the working distances, angle of attack, exposed surface, and the number of neurovascular structures present in the central trajectory were analyzed.
The distances to the cranial and medial region of the olivary body were 52.71 mm (SD 3.59) from the
retrosigmoid approach and 27.94 mm (SD 3.99) from the far lateral; to the most basal region of the olivary body, the distances were 49.93 (SD 3.72) from the
retrosigmoid approach and 18.1 mm (SD 2.5) from the far lateral. The angle of attack to the caudal region was 19.44° (SD 1.3) for the
retrosigmoid approach and 50.97° (SD 8.01) for the far lateral approach; the angle of attack to the cranial region was 20.3° (SD 1.22) for the retrosigmoid and 39.9° (SD 5.12) for the far lateral. Regarding neurovascular structures, the probability of finding an arterial structure is higher for the lateral far, whereas a neural structure will be more likely from a retrosigmoid approach.
As conclusions of this work, we can say that far lateral approach presents more favorable conditions for the microsurgical treatment of intrinsic bulbar and bulbomedullary lesions approached through the caudal half of the olivary body. In those cases of bulbar and pontine-bulbar lesions approached through the cranial half of the olivary body, the retrosigmoid approach can be considered for selected cases.