Department of Neurosurgery, Nagoya City University Graduate School of Medical Science, Aichi, Japan; Interfaculty Initiative in Information Studies/Institute of Industrial Science, The University of Tokyo, Tokyo, Japan; Normal Pressure Hydrocephalus Center, Rakuwakai Otowa Hospital, Kyoto, Japan.
Medical System Research & Development Center, FUJIFILM Corporation, Tokyo, Japan.
World Neurosurg. 2023 Aug;176:e427-e437. doi: 10.1016/j.wneu.2023.05.077. Epub 2023 May 26.
The presence of tightened sulci in the high-convexities (THC) is a key morphological feature for the diagnosis of idiopathic normal pressure hydrocephalus (iNPH), but the exact localization of THC has yet to be defined. The purpose of this study was to define THC and compare its volume, percentage, and index between iNPH patients and healthy controls.
According to the THC definition, the high-convexity part of the subarachnoid space was segmented and measured the volume and percentage from the 3D T1-weighted and T2-weighted magnetic resonance images in 43 patients with iNPH and 138 healthy controls.
THC was defined as a decrease in the high-convexity part of the subarachnoid space located above the body of the lateral ventricles, with anterior end on the coronal plane perpendicular to the anterior commissure-posterior commissure (AC-PC) line passing through the front edge of the genu of corpus callosum, the posterior end in the bilateral posterior parts of the callosomarginal sulci, and the lateral end at 3 cm from the midline on the coronal plane perpendicular to the AC-PC line passing through the midpoint between AC and PC. Compared to the volume and volume percentage, the high-convexity part of the subarachnoid space volume per ventricular volume ratio < 0.6 was the most detectable index of THC on both 3D T1-weighted and T2-weighted magnetic resonance images.
To improve the diagnostic accuracy of iNPH, the definition of THC was clarified, and high-convexity part of the subarachnoid space volume per ventricular volume ratio <0.6 proposed as the best index for THC detection in this study.
大脑凸面脑沟变紧是特发性正常压力脑积水（iNPH）的一个关键形态学特征，但高凸面脑沟（THC）的确切位置尚未确定。本研究的目的是定义 THC，并比较 iNPH 患者与健康对照组之间 THC 的体积、百分比和指数。
根据 THC 的定义，对 43 例 iNPH 患者和 138 例健康对照者的三维 T1 加权和 T2 加权磁共振图像进行分割，测量高凸面脑沟蛛网膜下腔的体积和百分比。
THC 定义为侧脑室体上方的高凸面脑沟蛛网膜下腔减少，前界在冠状面垂直于前连合-后连合（AC-PC）线穿过胼胝体膝部前缘，后界在胼胝体缘沟的双侧后部，外侧界在冠状面垂直于 AC-PC 线穿过 AC 和 PC 中点的 3cm 处。与体积和体积百分比相比，3D T1 加权和 T2 加权磁共振图像上，THC 的最佳检测指标是蛛网膜下腔高凸面部分与脑室体积比<0.6。
为提高 iNPH 的诊断准确性，本研究明确了 THC 的定义，并提出蛛网膜下腔高凸面部分与脑室体积比<0.6 作为 THC 检测的最佳指标。
