Gamma Knife MR/CT/RTSTRUCT Sets With Hippocampal Contours

<p>This collection is comprised of 390 patients who presented with vestibular schwannoma (VS, n=73), trigeminal neuralgia (TGN, n=119) or metastatic disease (M, n=198, 4-26 metastases) and were subsequently treated with Gamma Knife (Elekta AB, Stockholm, Sweden) stereotactic radiosurgery. For each patient, the treatment indication is designated with a suffix on their patient ID (VS, TGN or M).</p><p>All patients are provided with at least one high-resolution (1 mm slice thickness) T1 FLASH trans-axial MR imaging study and their corresponding high-resolution axial planning CT. When available, treatment planning data (struct, dose, plan), alternative MR sequences (FLAIR, T2 CISS, etc.) and follow-up MR imaging studies were collected. Each MR image used during treatment planning was registered to the CT frame of reference and is provided with the DICOM registration file and the aligned secondary image. Additionally, for each patient in the cohort, hippocampal contours generated by multiple institutional observers are provided in a separate structure set. In total, this dataset contains: CT (n=390), MR (n=3868), REG (n=872), DOSE (n=928), PLAN (n=928), planning STRUCT (n=931), and hippocampal research STRUCT (n=390).</p><h3>Planning Data</h3><p>Gamma Knife planning studies are designated by “Gamma Knife Planning Data” in the study description DICOM header tag. For each patient, MIM (MIM Software, Beachwood, OH) was used to generate a rigid registration between CT and each MR sequence and the registration accuracy was validated using the stereotactic frame fiducial markers. From each registration, a DICOM RTREG file and aligned secondary are provided with each aligned secondaries series indicated by “[original series description] Co-registered to CT” in the series description DICOM header tag. During export from GammaPlan (Elekta AB, Stockholm, Sweden), the treatment planning files are provided in duplicate for each imaging modality frame of reference (CT and each MR sequence). Treatment planning structure names were renamed to remove misspellings, synonyms, and identifiable information. Structures with the format Plan1[tgt#]#Gy denote each target volume (a, b, ...) and the dose to the specified target in Gray. For patients with multiple lesions, ROI structure names are given as the brain region followed by the relative anatomical directions (e.g. Lobe_Frontal_R, Lobe_Parietal_L). Any empty contours were preserved but are designated with '(Empty)' in the name.</p><h3>Follow-up Data</h3><p>When available, patient follow-up images were collected between the provided treatment date and either the next Gamma Knife treatment or up-to approximately two years following treatment. In total, 197 patients are provided with follow-up imaging studies, with a median of 2 (range 1-13) follow-up studies provided per patient. Each follow-up imaging study is designated as “Follow-up Image Set #” in the Study Description. Each follow-up study exists in a unique frame of reference and was not co-registered to the original treatment planning CT volume.</p><h3>Hippocampal Contours</h3><p>Three independent observers generated hippocampal contours from the CT aligned-secondary of the T1-weighted MR image, with the resultant contours saved to the CT frame of reference. In total, 744 unique left, right contour pairs were generated (observer 1, n=390; observer 2, n=247; observer 3, n=107). In addition to hippocampal contours, the region grow tool was used to generate a head contour (ROI name ‘head’) to mask out the stereotactic frame and remove most of the reconstruction artifacts on the inferior extent of the image volume.</p><h3>Additional Information</h3><p>All MR images designated as ‘Co-registered to CT’ in the Series Description were interpolated to the CT frame of reference, potentially altering the field of view or voxel resolution. For all co-registered MR images, the original primary images and registration files are provided for use as needed.</p>

本数据集由390名患者组成，其中73名患有前庭神经鞘瘤（VS），119名患有三叉神经痛（TGN）或转移性疾病（M，n=198，转移灶4-26个），他们随后接受了伽玛刀（Elekta AB，斯德哥尔摩，瑞典）立体定向放射外科治疗。对于每位患者，治疗指征通过在其患者ID后添加后缀进行标识（VS、TGN或M）。所有患者均至少提供了一项高分辨率（1毫米切片厚度）的T1 FLASH横断面MR成像研究及其相应的高分辨率横断面规划CT。当可用时，收集了治疗规划数据（结构、剂量、计划）、替代MR序列（FLAIR、T2 CISS等）和随访MR成像研究。每个用于治疗规划中的MR图像均注册到CT参考框架中，并提供了DICOM注册文件和对齐的次级图像。此外，对于队列中的每位患者，提供了由多个机构观察者生成的海马轮廓，存储在单独的结构集中。总体而言，该数据集包含：CT（n=390）、MR（n=3868）、REG（n=872）、DOSE（n=928）、PLAN（n=928）、规划结构（n=931）和海马研究结构（n=390）。

<h3>治疗规划数据</h3>
伽玛刀规划研究在研究描述DICOM头标签中指定为“伽玛刀规划数据”。对于每位患者，使用MIM（MIM Software，Beachwood，OH）生成CT与每个MR序列之间的刚性配准，并使用立体定向框架标志物验证了配准精度。从每个配准中，提供了一个DICOM RTREG文件和对齐的次级图像，其中每个对齐的次级图像系列在系列描述DICOM头标签中指示为“[原始序列描述]与CT共配准”。在从GammaPlan（Elekta AB，斯德哥尔摩，瑞典）导出时，为每种成像模态参考框架（CT和每个MR序列）提供了治疗规划文件的副本。治疗规划结构名称已重命名为去除拼写错误、同义词和可识别信息。格式为Plan1[tgt#]#Gy的结构表示每个目标体积（a、b、...）以及指定目标所在位置的剂量（以Gray为单位）。对于有多个病灶的患者，ROI结构名称以大脑区域后跟相对解剖方向给出（例如Lobe_Frontal_R、Lobe_Parietal_L）。任何空轮廓均予以保留，但在名称中指定为‘(Empty)’。

<h3>随访数据</h3>
当可用时，在提供的治疗日期与下一次伽玛刀治疗之间或治疗后的约两年内收集了患者随访图像。总共有197名患者提供了随访成像研究，每位患者提供了2次（范围1-13次）随访研究的中位数。每个随访成像研究在研究描述中指定为“随访图像集#”。每个随访研究存在于一个独特的参考框架中，并且没有与原始治疗规划CT体积共配准。

<h3>海马轮廓</h3>
三位独立观察者从T1加权MR图像的CT对齐次级图像中生成了海马轮廓，生成的轮廓保存到CT参考框架中。总共生成了744对独特的左右轮廓（观察者1，n=390；观察者2，n=247；观察者3，n=107）。除了海马轮廓外，还使用了区域生长工具生成头部轮廓（ROI名称‘head’）以屏蔽立体定向框架并移除图像体积下部的重建伪影。

<h3>附加信息</h3>
所有在系列描述中指定为‘与CT共配准’的MR图像均插值到CT参考框架中，可能改变视野或体素分辨率。对于所有共配准的MR图像，提供了原始主图像和注册文件供需要时使用。