Lymph node metastasis of oral cancer with 18FDG-PET

本文对7例鳞状细胞癌患者进行了PET和CT图像融合，并使用外部标记。本研究的目的是检查由此产生的误差和图像融合的临床用途。患者以舌、上颌牙龈或上颌窦为原发病灶。所有患者均行PET + FDG + CT检测肿瘤部位。7例患者中，6例经诊断影像及临床观察均有明显的颈部淋巴结转移。为了确保PET图像的解剖细节，在中耳和双耳垂下方放置了小的放射性标记物。然后在计算机上将PET图像和CT图像相互重叠。所有患者均实现PET与CT图像融合。检验了该方法在PET和CT图像之间的叠加误差。PET与CT图像的平均距离测量的拟合精度在2 ~ 5mm之间。PET-CT叠加图像显示肿瘤FDG摄取增加，FDG摄取到腭扁桃体也有定位。本文所描述的用于PET和CT图像对齐的标记系统可以在常规基础上使用，而无需侵入性固定外部标记物，改善头颈部癌患者的管理和随访。

The image fusion of PET and CT from the head and neck region was performed with the use of external markers in 7 patients with squamous cell carcinoma. The purpose of this study was to examine a resultant error and clinical usefulness of the image fusion.Patients had primary lesion of the tongue, the maxillary gingiva or the maxillary sinus. All patients underwent PET with FDG and CT to detect tumor sites. Of these 7 patients, 6 cases were also pronounced regional lymph node metastasis to the neck from the diagnostic images and the clinical observation. To ensure anatomical detail of the PET images, small radioactive markers were placed on the philtrum and below both earlobes. The PET image and CT image were then overlapped each other on a computer.The image fusion of PET and CT was achieved in all patients. The superposition error of this method was examined between PET and CT images. The accuracy of fit measured as the mean distance between PET and CT image was in the range of 2 - 5 mm. PET-CT superimposed images produced localization of tumor FDG uptake increase and FDG uptake to palatine tonsil were also localized.The marker system described here for the alignment of PET and CT images can be used on a routine bases without the invasive fixation of external markers, improve the management and follow up of patients with head and neck carcinoma.