Jung Tae-Young, Jung Shin, Ryu Han-Seung, Kim In-Young, Jang Woo-Youl, Moon Kyung-Sub, Lim Sa-Hoe, Kim Dong-Yeon, Kang Sae-Ryung, Min Jung-Joon, Bom Hee-Seung, Kim Seul-Kee, Kwon Seong Young
Department of Neurosurgery, Chonnam National University Medical School and Hwasun Hospital, Hwasun-gun, Republic of Korea.
Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, Hwasun-gun, Republic of Korea.
Stereotact Funct Neurosurg. 2019;97(4):217-224. doi: 10.1159/000503732. Epub 2019 Nov 6.
Although 11C-methionine positron emission tomography (MET-PET) images can be fused with magnetic resonance (MR) images using planning software for gamma knife radiosurgery (GKR), the stereotactic information has limited value in patients with recurrent malignant brain tumor due to the difference in imaging protocols between MET-PET and MR images. The aim of this study was to evaluate the clinical application of MR imaging (MRI)-deformed MET-PET images in GKR using a deformable registration tool.
We examined the enhanced MR stereotactic images, MET-PET and MRI-deformed MET-PET images without stereotactic information for 12 newly developed metastatic brain tumors. MET-PET and MRI-deformed MET-PET images were co-registered with the MR stereotactic images using radiosurgery planning software. Visual analysis was performed to determine whether the MET-PET and MR images matched better after using the deformable registration tool. In addition, the matching volume between MR and MET-PET images was compared before and after applying this tool. The matching volume was calculated as the metabolic tumor volume on the MET-PET images, including the MR-enhanced volume. The matching percentage was calculated as the matching volume divided by the MR-enhanced volume, multiplied by 100.
Visual analysis revealed that the MRI-deformed MET-PET images provided the same axial plane as that of the MR images, with the same window level, enabling easy identification of the tumor with the radiosurgery planning software. The mean matching percentage of the MET-PET/MR fusion images was 61.1% (range 24.7-94.7) and that of the MRI-deformed MET-PET/MR fusion images was 63.4% (range 20.8-94.3). No significant difference was found in the matching percentage between the two types of fusion images (p = 0.754).
The MRI-deformed MET-PET images enable utilization of the functional information when planning a treatment in GKR without significant volume change.
尽管使用伽玛刀放射外科手术（GKR）的计划软件可将11C-蛋氨酸正电子发射断层扫描（MET-PET）图像与磁共振（MR）图像融合，但由于MET-PET与MR图像成像协议的差异，立体定向信息在复发性恶性脑肿瘤患者中的价值有限。本研究旨在使用可变形配准工具评估MR成像（MRI）变形的MET-PET图像在GKR中的临床应用。
我们检查了12例新发生的脑转移瘤的增强MR立体定向图像、MET-PET以及无立体定向信息的MRI变形MET-PET图像。使用放射外科手术计划软件将MET-PET和MRI变形MET-PET图像与MR立体定向图像进行配准。进行视觉分析以确定使用可变形配准工具后MET-PET与MR图像是否匹配得更好。此外，比较应用该工具前后MR与MET-PET图像之间的匹配体积。匹配体积计算为MET-PET图像上的代谢肿瘤体积，包括MR增强体积。匹配百分比计算为匹配体积除以MR增强体积，再乘以100。
视觉分析显示，MRI变形的MET-PET图像与MR图像提供相同的轴向平面，具有相同的窗宽窗位，便于使用放射外科手术计划软件识别肿瘤。MET-PET/MR融合图像的平均匹配百分比为61.1%（范围24.7 - 94.7），MRI变形的MET-PET/MR融合图像的平均匹配百分比为63.4%（范围20.8 - 94.3）。两种融合图像的匹配百分比之间未发现显著差异（p = 0.754）。
MRI变形的MET-PET图像能够在GKR治疗计划中利用功能信息，且体积无明显变化。
