갑상선에 대한 초음파 유도 하 고주파 열소작: 개에서의 예비실험 연구

Abstract

목적: 개의 갑상선에 고주파 열소작술(radiofrequency ablation)을 시행하여 소작 범위와 합병 증을 알아보고 사람의 양성 또는 악성 갑상선 결절의 치료에 이용될 수 있는지를 알아 보고자 하였다.대상과 방법: 초음파 유도 하에 5마리 개의 10개의 갑상선을 대상으로 하였다. 5개의 갑상선을 20 wattage로 1분간 소작하였고(1군) 다른 5개의 갑상선을 20 wattage로 2분 간 소작하였다.(2군). 소작 전과 소작 직후, 24시간, 72시간, 1주 후에 초음파와 CT를 시행하여 소작 소견의 변화와 합병증을 알아 보았다. 소작 전과 소작 1주 후에 총 T3, 유리 T4, TSH 치를 측정하여 갑상선 기능에 변화가 있는지 알아 보았다. 소작 전, 소작 직후, 24시간, 72시간, 1주 후에 후 두경 검사를 시행하여 반회 신경마비 유무를 관찰하였다. 결과: 시술 직후 갑상선은 초음파에서 경계가 불분명한 고에코로 보이다가 24시간 후에는 정상 갑상선보다 저에코로 변화하였다. 소작 최대 직경은 1군에서 평균 9.4±0.5 mm였고 2군에서 평균 11.4±0.5 mm였다. 시술 직후의 조영 증강 전 CT에서는 갑상선의 소작 병변이 저밀도로 보였고 조영 증강 후에는 정상 갑상선과의 구분이 어려웠다. 합병증은 반회 신경마비 1예, 식도 파열 2예, 식도 벽 비후 5예에서 보였다. 요약하면, 개의 갑상선에 고주파 열소작술을 시행함으로써 사람에서 생긴 양성 또는 악성 갑상선 결절 중에서 반경 5 mm 전방에서 치료 효과를 얻을 수 있을 것으로 사료된다.

Purpose: The purpose of this study was to evaluate the possibility of using radiofrequency ablation as the treatment modality for the benign or malignant thyroid nodules in humans. Therefore, we examined the results of using radiofrequency ablation on the thyroid glands in dogs, in respect of the extent of the ablated tissue and the complications. Materials and Methods: Five dogs (10 lobes of the thyroid glands) were included in this study. US-guided radiofrequency ablation was undertaken with a 10mm, uncovered 17 gauge cool-tip needle. The power and duration was 20 wattage and 1 minute in five thyroid lobes (group 1) and 20 wattage and 2 minutes in another 5 thyroid lobes (group 2). The ultrasound scans and the pre-and post-enhancement CT scans were undertaken before and immediately after the procedures, and at 24 hours, 72 hours and 1 week later. The US and CT findings of the ablated tissue and complications were evaluated. Blood sampling was done at the pre-procedure time and 1 week later for evaluating the functional status of the thyroid gland. Laryngoscopy was done at the pre-procedure and post-procedure times, and at 24 hours, 72 hours and 1 week later for the evaluation of any recurrent laryngeal nerve palsy. Results: The echo pattern of the ablated thyroid gland at immediately after the radiofrequency ablation appeared as poorly marginated and hyperechoic. On the US obtained 24 hours after radiofrequency ablation, the echo pattern of the ablated thyroid gland was hypoechoic. The maximum diameters after RFA were 9.4±0.5 mm in group I and 11.4±0.5 mm in group II. The pre-enhanced CT scan taken at immediately after the radiofrequency ablation showed ill defined hypodense areas in the ablated thyroid gland. Differentiation between the normal and abnormal portions of the thyroid gland was difficult on the contrast enhanced CT scan. Complications induced by radiofrequency ablation were one recurrent laryngeal nerve palsy, two perforations of esophagus and five thickenings of the esophageal wall. In summary, the radiofrequency ablation therapy for the benign or malignant thyroid nodules located in anterior aspect (within a 5 mm radius) of the thyroid gland in human suggests this is an effective treatment, through this was an animal study performed on dogs.