ABSTRACT
PURPOSE: To describe expected imaging features on chest computed tomography (CT) after percutaneous radiofrequency ablation (RFA) of lung tumors, and their frequency over time after the procedure. METHODS: In this double-center retrospective study, we reviewed CT scans from patients who underwent RFA for primary or secondary lung tumors. Patients with partial ablation or tumor recurrence during the imaging follow-up were not included. The imaging features were assessed in pre-defined time points: immediate post-procedure, ≤4 weeks, 5-24 weeks, 25-52 weeks and ≥52 weeks. Late follow-up (3 and 5 years after procedure) was assessed clinically in 48 patients. RESULTS: The study population consisted of 69 patients and 144 pulmonary tumors. Six out of 69 (9%) patients had primary lung nodules (stage I) and 63/69 (91 %) had metastatic pulmonary nodules. In a patient-level analysis, immediately after lung RFA, the most common CT features were ground glass opacities (66/69, 96 %), consolidation (56/69, 81 %), and hyperdensity within the nodule (47/69, 68 %). Less than 4 weeks, ground glass opacities (including reversed halo sign) was demonstrated in 20/22 (91 %) patients, while consolidation and pleural thickening were detected in 17/22 patients (77 %). Cavitation, pneumatocele, pneumothorax and pleural effusions were less common features. From 5 weeks onwards, the most common imaging features were parenchymal bands. CONCLUSIONS: Our study demonstrated the expected CT features after lung RFA, a safe and effective minimally invasive treatment for selected patients with primary and secondary lung tumors. Diagnostic and interventional radiologists should be familiar with the expected imaging features immediately after RFA and their change over time in order to avoid misinterpretation and inadequate treatments.
ABSTRACT
OBJETIVO: Relatar uma série de casos de endoleaks, com descrição da classificação vigente. MATERIAIS E MÉTODOS: Realizou-se um estudo retrospectivo dos endoleaks diagnosticados em nossa instituição, entre 2005 e 2009. Foram incluídos 20 casos, utilizados para ilustrar os diferentes tipos de endoleaks. RESULTADOS: Setenta por cento dos pacientes eram do sexo masculino. A idade variou entre 43 e 91 anos, média de 76,3 anos. Treze casos foram observados na aorta abdominal infrarrenal, quatro na aorta torácica, dois nas artérias ilíacas e um no território carotídeo. A ultrassonografia foi o método utilizado para o diagnóstico em 3 casos e a tomografia computadorizada, nos outros 17 casos. Classificação: tipo I, 60 por cento; tipo II, 25 por cento; tipo III, 15 por cento. Não foram observados os demais tipos nesta série. CONCLUSÃO: O diagnóstico precoce e a correta classificação são fundamentais para o manejo adequado dos casos de endoleaks, tornando o conhecimento de seus subtipos conceito fundamental na formação do médico especialista em radiologia e diagnóstico por imagem e para o cirurgião vascular.
OBJECTIVE: To describe a series of endoleak cases and their respective classification. MATERIALS AND METHODS: The authors developed a retrospective study of endoleaks diagnosed at their institution in the period between 2005 and 2009. Twenty cases were included to illustrate the different types of endoleaks. RESULTS: Seventy percent of the patients were men, and the ages ranged from 43 to 91 years (mean, 76.3 years). Thirteen cases were observed in the infrarenal abdominal aorta, four in the thoracic aorta, two in the iliac artery, and one in the carotid territory. Ultrasonography was the method utilized for diagnosis in three cases, and computed tomography in the other 17 cases. Classification: 60 percent type I, 25 percent type II, 15 percent type III. Other endoleak types were not observed in the present series. CONCLUSION: Early diagnosis and correct classification of endoleaks are crucial for an appropriate management of cases. The knowledge of endoleaks subtypes is fundamental in the education of physicians specialized in radiology and imaging diagnosis as well as for vascular surgeons.
