Glicksohn J, Myslobodsky M S
Department of Psychology, Tel-Aviv University, Ramat Aviv, Israel.
Neuropsychologia. 1993 Feb;31(2):145-59. doi: 10.1016/0028-3932(93)90043-y.
Hemispheric asymmetries were examined in 20 normal individuals who underwent MR scanning. The asymmetry indices were represented for a series of contiguous, consecutive coronal images through the occipital and frontal lobes, along the dorso-ventral [DV] axis. A monotonic decrease in size of the parieto-occipital hemispheric areal asymmetry was observed, from a marked left predominance to a greater degree of symmetry. When frontal and occipital lobe asymmetries were compared, the familiar frontal-right vs occipital-left counterclockwise torque was observed, but was found to be more prominent in the dorsal aspect of the frontal cuts and the ventral aspect of the occipital cuts. At the individual level, a within-subject linear model for predicting cerebral area as a function of cut, hemisphere and DV, revealed this marked DV effect. The use of the within-subject linear model further enabled the individual assessment of structural asymmetries, and provided criteria by which subjects could be grouped. We further show how a deviation of the occipital falx will engender different hemispheric asymmetries, depending on the orientation of the coronal imaging plane. Given the latter, we recommend planning the coronal cuts based on a low-ventricular transaxial scout, wherein the deviated falx, if present, can be taken into account.
对20名接受磁共振扫描的正常个体进行了半球不对称性检查。不对称指数通过沿背腹[DV]轴穿过枕叶和额叶的一系列连续冠状图像来表示。观察到顶枕半球面积不对称性大小呈单调下降，从明显的左侧优势到更高程度的对称性。比较额叶和枕叶不对称性时，观察到常见的额叶-右侧与枕叶-左侧逆时针扭矩，但发现其在额叶切片的背侧和枕叶切片的腹侧更为明显。在个体水平上，一个用于预测脑区面积与切片、半球和DV关系的受试者内线性模型揭示了这种明显的DV效应。使用受试者内线性模型进一步能够对结构不对称性进行个体评估，并提供了对受试者进行分组的标准。我们进一步展示了枕叶镰的偏差如何根据冠状成像平面的方向产生不同的半球不对称性。鉴于此，我们建议基于低脑室横轴定位像来规划冠状切片，其中如果存在偏差的镰，可以将其考虑在内。
