鼻咽癌放疗后迟发性放射性脑病的PET/CT影像分型  

PET/CT-based classification of delayed radiation encephalopathy following radiotherapy for nasopharyngeal carcinoma

作　　者：王欣璐[1] 尹吉林[1] 李向东[1] 李兴耀[1] 欧阳习[1] 周峥[1] 郑辉[1] 

机构地区：[1]广州军区广州总医院核医学科PET/CT中心,广东广州510010

出　　处：《南方医科大学学报》2008年第3期320-323,共4页Journal of Southern Medical University

基　　金：国家自然科学基金(30500136)~~

摘　　要：目的研究鼻咽癌放疗后放射性脑病(RE)的PET/CT影像学表现,观察大脑颞叶的代谢改变规律,根据其影像学表现进行分型,以期为放射性脑病的准确诊断提供诊断依据和标准。方法本组共53例均为鼻咽癌(经活检病理确诊)行根治性放疗后,经过临床症状及CT和(或)MRI平扫加增强诊断为RE的患者。患者均依次进行全身和头部的扫描成像;并将临床资料与PET/CT影像学资料相结合进行分析。结果最常见的放射性脑病累及的部位是双侧或单侧颞叶下极,本组中PET显示双侧颞叶代谢均明显降低者35例(即70个颞叶),单侧颞叶代谢减低者18例(即18个颞叶)。根据PET/CT的影像学表现,将所有病例分为三型:水肿型(56个颞叶)、液化坏死型(10个颞叶)及萎缩钙化型(22个颞叶)。1例水肿型的患者经过及时治疗后,病变区脑组织水肿完全恢复正常密度,代谢也恢复至正常;但2例水肿型进一步加重演变为萎缩钙化型;2例液化坏死型演变为萎缩钙化型。结论根据RE的PET/CT表现将其分为水肿型、液化坏死型及萎缩钙化型共三型;第一、第二型可以向第三型演变。Objective To investigate positron-emission tomography-computed tomography （PET/CT） findings of radiation encephalopathy （RE） following radiotherapy for nasopharyngeal carcinoma （NPC）, observe the metabolic changes of the compromised brain tissues, and postulate the clinical classification of RE to provide reference for its diagnosis. Methods This study included 53 pathologically confirmed NPC patients who received previous radical radiotherapy, and the diagnosis of RE was established according to the clinical manifestations and CT/PET findings. All the patients underwent PET/CT whole-body and head scans, and the image data were evaluated along with the clinical data of the patients. Results RE most frequently involved the lateral or bilateral inferior temporal lobes. PET identified hypometabolic changes in the bilateral temporal lobes of 35 patients （70 lobes） and in the lateral temporal lobe of 18 patients （18 lobes）. According to the PET/CT findings, the lesions were classified into 3 types, namely the oedema type （56 temporal lobes）, liquefactive necrosis type （10 temporal lobes）, and atrophic calcification type （22 temporal lobes）. One patient with oedema type lesion received neurotrophic treatment and recovered completely with normal brain tissue density and metabolism, but the oedema type lesions in 2 patients progressed into to atrophic calcification type; the liquefactive necrotic lesions in another 2 patients also progressed into atrophic calcification type. Conclusion RE patients exhibit significant hypometabolic changes in the inferior temporal lobe on PET. According to the findings by PET/CT, RE can be classified into the oedema type, liquefactive necrosis type, and atrophic calcification type, and lesions of the former two types may progress into the third type.

关 键 词：鼻咽癌 放射治疗 放射性脑病 正电子发射断层显像/计算机断层显像 

分 类 号：R739.63[医药卫生—肿瘤] R818[医药卫生—临床医学]