Alan Albert F, Ennabe Michelle, Wessel Bambi, Klassen Bryan T, Miller Kai
Neurological Surgery, Mayo Clinic, Rochester, USA.
Neurology, Mayo Clinic, Rochester, USA.
Cureus. 2023 Jul 2;15(7):e41280. doi: 10.7759/cureus.41280. eCollection 2023 Jul.
The cerebral cortex, comprising six layers known as the neocortex, is a sheet of neural tissue that contains regions for neurosurgical planning, including the primary motor cortex (PMC), the supplementary motor cortex (SMA), and the primary somatosensory cortex (PSC). However, knowledge gaps persist concerning the transition points between areas 3 to 4 and 4 to 6 and the SMA's extent. This study aims to develop a non-invasive protocol using T1/T2 weighted imaging to identify crucial anatomic borders around the primary and supplementary motor cortex for neurosurgical planning. A comprehensive literature search on the cytoarchitectonic borders of Brodmann's areas 3a, 4, and 6 was conducted, and relevant articles were selected based on their examination of these borders. The primary motor cortex was found to be the thickest region in the human brain, with discernible differences in thickness between areas 4 and 6. T2-weighted images revealed significant cortical thickness differences between the precentral and postcentral gyrus. Various methods have been employed to parcellate borders between cortical regions, including Laplace's equation and equi-volume models. A triple-layer appearance in the primary motor cortex and a novel method based on myelin content demonstrated consistent agreements with historically defined cytoarchitectonic borders. However, differentiating areas 4 and 6 from MR imaging remains challenging. Recent studies suggest potential methods for pre-surgically identifying the primary motor cortex and examining differences in cortical thickness in diseases. A protocol should be established to guide neurosurgeons in accurately identifying areas 4 and 6, possibly using imaging modalities superimposed on myelin maps for differentiation and determining area 6's anterior extent.
大脑皮层由称为新皮层的六层组成，是一片神经组织，包含用于神经外科手术规划的区域，包括初级运动皮层（PMC）、辅助运动皮层（SMA）和初级体感皮层（PSC）。然而，关于3区到4区以及4区到6区之间的过渡点和SMA的范围，仍存在知识空白。本研究旨在开发一种使用T1/T2加权成像的非侵入性方案，以确定初级和辅助运动皮层周围的关键解剖边界，用于神经外科手术规划。对Brodmann 3a、4和6区的细胞构筑边界进行了全面的文献检索，并根据对这些边界的研究选择了相关文章。发现初级运动皮层是人类大脑中最厚的区域，4区和6区之间的厚度存在明显差异。T2加权图像显示中央前回和中央后回之间存在显著的皮质厚度差异。已经采用了各种方法来划分皮质区域之间的边界，包括拉普拉斯方程和等体积模型。初级运动皮层中的三层外观以及基于髓磷脂含量的新方法与历史定义的细胞构筑边界显示出一致的一致性。然而，从磁共振成像中区分4区和6区仍然具有挑战性。最近的研究提出了术前识别初级运动皮层和检查疾病中皮质厚度差异 的潜在方法。应该建立一个方案来指导神经外科医生准确识别4区和6区，可能使用叠加在髓磷脂图谱上的成像模态进行区分，并确定6区的前部范围。
