Bang Myung Hoon, Shin JinShik, Lee Kwan Seop, Kang Min Jae
Department of Pediatrics Department of Radiology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
Medicine (Baltimore). 2018 Apr;97(14):e0282. doi: 10.1097/MD.0000000000010282.
As ultrasound is commonly used these days, more and more lesions are found incidentally, including simple cysts, isoechoic nodules, and hypoechoic nodules, such as ectopic thymus. We here report the prevalence of ectopic thymus and its natural course.We retrospectively reviewed the charts of 690 subjects (342 males, 348 females) who were under 18 years old and had undergone neck or thyroid ultrasound at Hallym University Sacred Heart Hospital from January 2014 to June 2017. Ectopic thymus was defined when the incidental lesion was hypo- to iso-echoic compared to adjacent muscles with vascularity and did not have a connection to the thymus in the mediastinum.Of the 690 children, 16 (9 males, 7 females; median and ranges of age at diagnosis, 13 months and 18 days to 10 years) were diagnosed as having ectopic thymus. The most common location of ectopic thymus was in the inferior aspect of the left thyroid lobe. The median and ranges of the longest diameter at the time of initial diagnosis was 22.5 mm and 8 mm to 38 mm, respectively. Four cases underwent follow-up ultrasound, of which 3 cases showed no change in size and 1 case showed decreased size.Ectopic thymus should be kept in mind when a lesion is found in the neck and thyroid incidentally, and physicians should reassure parents about its benign course.
如今超声检查被广泛应用，越来越多的病变被偶然发现，包括单纯囊肿、等回声结节和低回声结节，如异位胸腺。我们在此报告异位胸腺的发生率及其自然病程。我们回顾性分析了2014年1月至2017年6月在韩林大学圣心医院接受颈部或甲状腺超声检查的690例18岁以下患者（342例男性，348例女性）的病历。当偶然发现的病变与相邻肌肉相比为低回声至等回声且有血管，且与纵隔内的胸腺无连接时，定义为异位胸腺。在这690名儿童中，16例（9例男性，7例女性；诊断时年龄中位数及范围为13个月18天至10岁）被诊断为异位胸腺。异位胸腺最常见的位置是左甲状腺叶下缘。初次诊断时最长径的中位数及范围分别为22.5mm和8mm至38mm。4例患者接受了超声随访，其中3例大小无变化，1例大小减小。当颈部和甲状腺偶然发现病变时，应考虑异位胸腺的可能，医生应向家长说明其良性病程，使其安心。
