定义指套征,也称牙膏征,最初用于描述胸片上支气管树的黏液嵌塞,表现为分枝管状、牙膏样或手指样的密度影,肺部影像表现为自肺门指向外周的分枝状或指头状高密度影,呈 V 形、Y 形分支状及葡萄串样,典型者影像仿佛手指的形状。最早被用于描述变应性支气管肺曲霉病的影像特点,其病理机制为支气管黏液嵌塞[1]。常见疾病任何引起气道阻塞性的疾病均可出现指套征。良性及恶性肿瘤(图)可引起气道阻塞,导致远端支气管扩张及黏液嵌顿,气道发育畸形,如支气管闭锁,常表现为指套征,支气管结石、支气管结核及缩窄、叶内型肺隔离征及异物吸入也可引起黏液嵌顿及指套征,变应性支气管肺曲霉菌病(allergic bronchopulmonary as pergillosis,ABPA)及囊性纤维化(伴或不伴ABPA)是最常见的两种能引起指套征的非梗阻性疾病。分布先天性支气管闭锁常累及肺门旁的气道支气管,结石的特征性表现为支气管周钙化性结节,常累及段支气管,支气管结核可累及中等大小的支气管,CT上状似动脉瘤,ABPA特征性累及中心气道,以段或亚段支气管较为常见。囊性纤维化常可见位于中、上肺野的黏液栓塞和支气管扩张。
▲与上同一病例:冠状位CT重建显示高透光度及少血管的左肺(白箭头),及左下肺背段支气管局部闭锁。(病例来源:何婉雪,解立新.先天性支气管闭锁 1 例[J].解放军医学院学报.2017,38(11),1083-1085.)影像学诊断支气管闭锁的 CT 三联征:支气管局灶性中断,远端黏液嵌塞,阻塞肺段肺气肿改变[9]。黏液囊肿多表现为从肺门向周围肺实质延伸的分支管状或 结节状透明度增高影,也可位于周围肺野[10]。中央气道的黏液嵌塞在胸片上表现为特征性指套征[11]。如果同时存在黏液囊肿、以黏液囊肿为中心的闭塞支气管、周围肺组织 的肺气肿改变,且能由支气管镜排除肿瘤、异物、炎性狭窄引起的获得性支气管闭锁,则CBA诊断成立[10]。参考文献:[1]高健,夏春伟.变应性支气管肺曲霉菌病的影像学特点分析[J].临床肺科杂志,2013,18(12):2299-2300.[2]Singh SI, Agarwal R. Pulse methylprednisolone in allergic bronchopulmonary aspergillosis exacerbations. Eur Respir Rev, 2014, 23(131): 149-152.[3]Agarwal R, Chakrabarti A, Shah A, et al. Allergic bronchopulmonary aspergillosis: review of literature and proposal of new diagnostic and classification criteria. Clin Exp Allergy, 2013, 43(8): 850-873.[4]中华医学会呼吸病学分会哮喘学组. 变应性支气管肺曲霉病诊 治专家共识. 中华医学杂志, 2017, 97(34): 2650-2656.[5]Sunzini F, Barbato C, Canofari C, et al. Clinical and radiological signs of ABPA associated with airways infection with Aspergillus in the absence of specific IgE. Eur Ann Allergy Clin Immunol, 2016, 48(5): 202-204.[10] Schwartz HJ, Greenberger PA. The prevalence of allergic bronchopulmonary aspergillosis in patients with asthma, determined by serologic and radiologic criteria in patients at risk. J Lab Clin Med, 1991, 117(2): 138-142.[6] 陆海雯, 卫平, 徐金富. 变应性支气管肺曲霉病的诊断标准变迁 及影像学分类进展. 中国呼吸与危重监护杂志, 2014, 13(5): 534-536.[7]Schuster SR,Harris GB,Williams A,et al.Bronchial atresia:a recognizable entity in the pediatric age group[J].J Pediatr Surg, 1978(13):682-689.[8] Meng RL,Jensik RJ,Faber LP,et al.Bronchial atresia[J].Ann Thorac Surg,1978(25):184-192.[9] Cohen AM, Solomon EH, Alfidi RJ. Computed tomography in bronchial atresia[J]. AJR Am J Roentgenol, 1980, 135(5):1097-1099.[10] Wang Y, Dai W, Sun Y, et al. Congenital bronchial atresia :diagnosis and treatment[J]. Int J Med Sci, 2012, 9(3):207- 212.[11] Apiliogullari B, Yav an M. Bronchial atresia with finger-in-glove sign[J/OL]. http ://casereports.bmj.com/content/2014/bcr-2014- 204587.long.注:部分文字来自《肺部CT精解》原著 Kyung Soo Lee;Joungho Han;Man Pyo Chung;Yeon Joo Jeong主审:许乙凯、王贵生。主译:吴元魁、蔡开灿 终点不是梦,重点是突破,仅供学习,不妥之处,敬请指正!