MARCOS ROBERTO DE MENEZES
Projetos de Pesquisa
Unidades Organizacionais
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina
4 resultados
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- Radiomic analysis of MRI to Predict Sustained Complete Response after Radiofrequency Ablation in Patients with Hepatocellular Carcinoma - A Pilot Study(2021) HORVAT, Natally; ARAUJO-FILHO, Jose De Arimateia B.; ASSUNCAO-JR, Antonildes N.; MACHADO, Felipe Augusto de M.; SIMS, John A.; ROCHA, Camila Carlos Tavares; OLIVEIRA, Brunna Clemente; HORVAT, Joao Vicente; MACCALI, Claudia; PUGA, Anna Luisa Boschiroli Lamanna; CHAGAS, Aline Lopes; MENEZES, Marcos Roberto; CERRI, Giovanni GuidoOBJECTIVES: To investigate whether quantitative textural features, extracted from pretreatment MRI, can predict sustained complete response to radiofrequency ablation (RFA) in patients with hepatocellular carcinoma (HCC). METHODS: In this IRB-approved study, patients were selected from a maintained six-year database of consecutive patients who underwent both pretreatment MRI imaging with a probable or definitive imaging diagnosis of HCC (LI-RADS 4 or 5) and loco-regional treatment with RFA. An experienced radiologist manually segmented the hepatic nodules in MRI arterial and equilibrium phases to obtain the volume of interest (VOI) for extraction of 107 quantitative textural features, including shape and first- and second-order features. Statistical analysis was performed to evaluate associations between textural features and complete response. RESULTS: The study consisted of 34 patients with 51 treated hepatic nodules. Sustained complete response was achieved by 6 patients (4 with single nodule and 2 with multiple nodules). Of the 107 features from the arterial and equilibrium phases, 20 (18%) and 25 (23%) achieved AUC >0.7, respectively. The three best performing features were found in the equilibrium phase: Dependence Non-Uniformity Normalized and Dependence Variance (both GLDM class, with AUC of 0.78 and 0.76, respectively) and Maximum Probability (GLCM class, AUC of 0.76). CONCLUSIONS: This pilot study demonstrates that a radiomic analysis of pre-treatment MRI might be useful in identifying patients with HCC who are most likely to have a sustained complete response to RFA. Second-order features (GLDM and GLCM) extracted from equilibrium phase obtained highest discriminatory performance.
- State-of-the-art in radiomics of hepatocellular carcinoma: a review of basic principles, applications, and limitations(2020) SANTOS, Joao Manoel Miranda Magalhaes; OLIVEIRA, Brunna Clemente; ARAUJO-FILHO, Jose de Arimateia Batista; ASSUNCAO- JR., Antonildes N.; MACHADO, Felipe Augusto de M.; ROCHA, Camila Carlos Tavares; HORVAT, Joao Vicente; MENEZES, Marcos Roberto; HORVAT, NatallyRadiomics is a new field in medical imaging with the potential of changing medical practice. Radiomics is characterized by the extraction of several quantitative imaging features which are not visible to the naked eye from conventional imaging modalities, and its correlation with specific relevant clinical endpoints, such as pathology, therapeutic response, and survival. Several studies have evaluated the use of radiomics in patients with hepatocellular carcinoma (HCC) with encouraging results, particularly in the pretreatment prediction of tumor biological characteristics, risk of recurrence, and survival. In spite of this, there are limitations and challenges to be overcome before the implementation of radiomics into clinical routine. In this article, we will review the concepts of radiomics and their current potential applications in patients with HCC. It is important that the multidisciplinary team involved in the treatment of patients with HCC be aware of the basic principles, benefits, and limitations of radiomics in order to achieve a balanced interpretation of the results toward a personalized medicine.
- Lung radiofrequency ablation: post-procedure imaging patterns and late follow-up(2020) ARAUJO-FILHO, Jose de Arimateia Batista; MENEZES, Raonne Souza Almeida Alves; HORVAT, Natally; PANIZZA, Pedro Sergio Brito; BERNARDES, Joao Paulo Giacomini; DAMASCENO, Rodrigo Sanford; OLIVEIRA, Brunna Clemente; MENEZES, Marcos RobertoPurpose: 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 followup 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.
- Systemic Air Embolism after Percutaneous Lung Biopsy: A Manageable Complication(2017) FIORE, Lucas; FRENK, Nathan Elie; MARTINS, Guilherme Lopes Pinheiro; VIANA, Publio Cesar Cavalcante; MENEZES, Marcos Roberto deCT-guided percutaneous biopsy is a resourceful and widely used tool to evaluate pulmonary nodules that frequently avoids costly and unnecessary surgeries. Severe complications occur in less than 1% of cases and include gas embolism, which is rarely documented. We report a case of gas embolism after transthoracic biopsies and discuss the pathophysiology and the benefits of early diagnosis and proper management.