计算机科学 ›› 2025, Vol. 52 ›› Issue (10): 115-122.doi: 10.11896/jsjkx.240700135
郑涵元1, 葛荣骏2, 何升级3, 李楠4
ZHENG Hanyuan1, GE Rongjun2, HE Shengji3, LI Nan4
摘要: PET衰减校正技术在临床上具有重要意义,其能够有效降低癌症误诊率并制定更为精确的治疗计划。然而,传统的PET衰减校正方法面临扫描时间较长和后期处理引入误差等问题,限制了其应用范围。近期,基于PET直接生成CT的衰减校正方法凭借更短的扫描时长和无后期处理误差的优势,逐渐流行于临床应用。然而,由于PET与CT之间的语义差异巨大且不对齐,使得PET直接生成CT的衰减方法在模态生成中面临着巨大的挑战。针对这一挑战,提出了一种基于Cycle-S2SCT-Net生成网络的PET衰减校正方法。Cycle-S2SCT-Net在整体上借助循环生成对抗结构学习PET与CT分布变换映射,实现了PET与CT两种模态间的语义转换。在单个生成对抗网络内部,Cycle-S2SCT-Net集成了成像切片连续性模块,以增强网络的语义对齐能力,从而提高生成成像的连续性和准确性。此外,还引入了网络特征层损失函数(Layer Loss),以增强生成网络的特征提取能力。实验结果表明,Cycle-S2SCT-Net生成的CT及其衰减校正后的PET,在定量评估指标峰值信噪比(PSNR)、结构相似性(SSIM)、均方根误差(RMSE),以及可视化结果上均表现出色。
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