透明隔间腔的MR影像解剖学研究

目的探讨透明隔间腔的透明隔腔(CSP)和韦尔加腔(CV)的MRI特点并对其进行影像学分型,以便在选择手术入路时作为辅助参考。方法纳入2019年1—4月上海交大医学院附属仁济医院行常规5.0 mm层厚头颅MR扫描的患者200例,观察透明隔间腔的出现概率和形态学特点,进行影像学分型。针对临床最为常见的CSP类型,纳入2018年3月—2019年3月难治性癫痫患者75例,行1.0~2.0 mm薄层MR扫描,经图像融合和三维重建,分别在横断面、冠状面图像中测量CSP长、宽、高的最大径,计算平均值。结果200例头颅常规MR扫描,可以观察到CSP者189例(94.5%),提示存在显性CSP者占大多数。CSP通常显示在经室间孔层面及其上方1个层面,位于胼胝体膝部的后方和穹窿柱的前上方。将CSP进行MR影像学分型:闭合型(Ⅰ型)、间隙型(Ⅱ型)、扩张型(Ⅲ型)、囊肿(Ⅳ型)和畸形变异(Ⅴ型)5个类型,分别占比4.5%(9/200)、91.5%(183/200)、1.5%(3/200)、1.5%(3/200)和1.0%(2/200)。CV按影像学可分为:单独出现或者与CSP融合,各占比1.0%(2/200)和1.5%(3/200)。最常见的CSP间隙型(Ⅱ型)的三维形态学测量,MRI可见的长、宽、高,均值为2.3 mm、1.5 mm、3.6 mm。结论CSP在MRI呈现多种形态,体积大小差别不一。术前通过MRI判断CSP是否存在以及CSP分型,可以作为选择透明隔分离方式和手术路径的重要参考指标。

MR imaging and anatomical study of cavum septum pellucidum et vergae

Objective To study the morphologic characteristics and classification of the cavum septum pellucidum (CSP) and the cavum vergae (CV) by MR scanning, as an aid for optimizing surgical approaches.Methods From January to April 2019, 200 patients with conventional 5.0 mm thick cranial MR scans were enrolled at Renji Hospital, School of Medicine, Shanghai Jiaotong University. The incidence of CSP was observed and its morphological characteristics were studied. Furthermore, thin-layer MRI scanning with 1.0-2.0 mm slices was performed in 75 patients diagnosed with drug-resistant epilepsy admitted to presurgical evaluation from March 2018 to March 2019. After image fusion and three-dimensional reconstruction, the maximum diameter of length, width and height of CSP was measured in horizontal and coronal images, and the average value was calculated.Results CSP was presented on conventional MR scans in 189 of 200 patients (94.5%), suggested that most patients had visible CSP. CSP was usually displayed at the level of the foramen of Monro and at the lowest level of the body of the lateral ventricles, which located just posterior to the genu of the corpus callosum and anterosuperior to the columns of the fornix. An imaging classification of CSP had been developed: close (typeⅠ), gap (typeⅡ), dilation (typeⅢ), cyst (type Ⅳ)and variations (typeⅤ), accounts for 4.5%(9/200)、91.5%(183/200)、1.5%(3/200)、1.5%(3/200) and 1.0%(2/200) of cases in this series, respectively. Two types of CV were identified according to imaging: isolated occurrence or communicating with CSP, accounts for 1.0%(2/200) and 1.5%(3/200) of cases, respectively. For the most common clinical type of CSP (typeⅡ), the average transverse, vertical, and longitudinal dimensions for CSP were 2.3 mm, 1.5 mm, and 3.6 mm, respectively.Conclusions CSP shows different shapes and sizes on MRIs. Preoperative MRI assessment of the presence of CSP and its morphological features can be used as an important reference index the CSP separation and the selection of surgical approach.