Anatomic study of endoscopic keyhole transtentorial transcollateral sulcus approach to the lateral ventricle

Abstract

Objective To perform the endoscopic transtentorial transcollateral sulcus(ETCS) approach to the atrium of lateral ventricle and discuss its technical essentials. Methods Ten formalin-fixed adult cadaveric heads (20 hemispheres) were included in this study. Firstly, the anatomic structures around the atrium were observed and examined in 5 cadaveric heads. In the coronal position through the posterior corpus callosum, the shortest distances from the depth of the collateral sulcus (CS) to the floor of the atrium, and the vertical distances from the posterior corpus callosum to the occipital pole were measured. Next, the endoscope was introduced into the atrium via the supracerebellar transtentorial transcollateral sulcus approach in the other 5 cadaveric heads. During the procedures, the related structures were observed and recorded. Results The CS had a relatively constant relationship with the lateral ventricle and the optic radiation fibers cover the lateral aspect of the atrium. In the coronal position through the posterior corpus callosum, the mean shortest distances from the depth of the CS to the floor of the atrium was (4.24±0.98)mm, and the mean vertical distances from the posterior corpus callosum to the occipital pole was (41.26±2.78)mm. The ETCS approaches to the atrium were performed successfully through a paramedian occipital keyhole window, and the atrium and posterior part of the body of the lateral ventricle could be observed clearly with a looking-up view. Conclusions The results of this study suggest that the ETCS approach can provide a sufficient exposure for the atrium and posterior part of the body of the lateral ventricle with a minimal invasive corridor avoiding the injury to the visual or language function. This method can be used as an available option to treat the lesions located in the atrium in selected cases. Key words: Lateral ventricle; Collateral sulcus; Endoscope; Keyhole; Applied anatomy