MARIA CRISTINA CHAMMAS
Projetos de Pesquisa
Unidades Organizacionais
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Hospital das Clínicas, Faculdade de Medicina
7 resultados
Resultados de Busca
Agora exibindo 1 - 7 de 7
- Ultrasonography on the non-living. Current approaches.(2023) THOMSEN, Thomas; BLAIVAS, Michael; SADIVA, Paulo; KRIPFGANS, Oliver D.; CHAN, Hsun-Liang; DONG, Yi; CHAMMAS, Maria Cristina; HOFFMANN, Beatrice; DIETRICH, Christoph F.The vast majority of clinicians associate diagnostic ultrasound with a tool that is designed for the living patient. However, it is of course possible to apply this imaging technology to evaluate the recently deceased patient for postmortem diagnosis, or even just examine postmortem tissue. We describe several cases in which ultrasound-enabled providers obtain answers in postmortem examinations and discuss potential future strategies and applications. In addition, we will also illustrate the use of sonography in minimally invasive post-mortem tissue sampling (MITS), an approach that can be used in post-mortem minimally invasive autopsies as well as for establishing ultrasound diagnostic parameters in new medical fields such as periodontal and dental implant specialties.
- Diaphragmatic mobility assessed by ultrasound is associated with thoracoabdominal asynchrony in severe to very severe COPD patients(2023) SANTOS, Juliana M. B.; REIS, Estefane C. M.; LINO, Pedro L.; LUNARDI, Adriana C.; SILVA, Cibele C. B. M.; PINTO, Thiago F.; CARVALHO-PINTO, Regina M.; CUKIER, Alberto; CHAMMAS, Maria C.; CARVALHO, Celso R. F.
- Ultrasonography in the Assessment of Tumors of the Cheek: Water Mouth Distension Technique(2023) CHAMMAS, Maria Crisitna; TAKAHASHI, Marcelo Straus; MOYSES, Raquel Ajub; POMPEIA, Celine; TAVARES, Marcos Roberto; CERRI, Giovanni GuidoPurpose To describe a new B-mode ultrasound examination technique to assess cheek tumors. Materials and Methods 30 cheek oral cavity lesions of different histological types (11 benign and 19 malignant) from 23 patients (11 women and 12 men, 7-82 years old, mean age of 49.5 years) were analyzed. Transcutaneous oral B-mode ultrasound (5-12 MHz transducer) was carried out in two stages. Initially it was performed conventionally with an empty mouth. Next, the patient was asked to keep their oral cavity filled with water (like when using a mouthwash) during imaging for the new test examination technique. The anatomical layers of this region and the characteristics of the tumors were evaluated. Lesions were classified as ill defined, partially defined, or defined. Conventional findings were compared to those of the new technique using the Wilcoxon signed-rank test. Ultrasound results were compared to histological findings analyzed by an independent team. Results The conventional empty mouth technique was able to confidently define lesion extension in only 6 of the 30 lesions, while the water-filled mouth technique was able to confidently define lesion extension in 29 of the 30 lesions (p<0.00001). Conclusion We present a novel technique that dramatically improves ultrasound staging of cheek oral cavity tumors. In addition to the increase in ultrasound accuracy, this technique does not require any special equipment or extra cost, is very well tolerated by patients, and thus should be considered in the evaluation of every patient undergoing transcutaneous cheek ultrasound for oral cavity lesion characterization.
- Ultrasound in cervical traumatic neuromas after neck dissection in thyroid carcinoma patients: descriptive analysis and diagnostic accuracy(2023) MARCOS, Vinicius Neves; DANILOVIC, Debora Lucia Seguro; PEREIRA, Fernando Linhares; TSUNEMI, Miriam Harumi; KULCSAR, Marco Aurelio Vamondes; HOFF, Ana Oliveira; DOMINGUES, Regina Barros; CHAMMAS, Maria Cristina; FREITAS, Ricardo Miguel Costa deObjective: Cervical traumatic neuromas (CTNs) may appear after lateral neck dissection for metastatic thyroid carcinoma. If they are misdiagnosed as metastatic lymph nodes (LNs) in follow-up neck ultrasound (US), unnecessary and uncomfortable fine-needle aspiration biopsy are indicated. The present study aimed to describe US features of CTNs and to assess the US performance in distinguishing CTNs from abnormal LNs. Subjects and methods: Retrospective evaluation of neck US images of 206 consecutive patients who had lateral neck dissection as a part of thyroid cancer treatment to assess CTN's US features. Diagnostic accuracy study to evaluate US performance in distinguishing CTNs from abnormal LNs was performed. Results: Eight-six lateral neck nodules were selected for analysis: 38 CTNs and 48 abnormal LNs. CTNs with diagnostic cytology were predominantly hypoechogenic (100% vs. 45%; P = 0.008) and had shorter diameters than inconclusive cytology CTNs: short axis (0.39 cm vs. 0.50 cm; P = 0.03) and long axis (1.64 cm vs. 2.35 cm; P = 0.021). The US features with the best accuracy to distinguish CTNs from abnormal LNs were continuity with a nervous structure, hypoechogenic internal lines, short/long axis ratio = 0.42, absent Doppler vascularization, fusiform morphology, and short axis = 0.48 cm. Conclusion: US is a very useful method for assessing CTNs, with good performance in distinguishing CTNs from abnormal LNs.
- Ultrasonography in the Assessment of Tumors of the Cheek: Water Mouth Distension Technique (Apr, 10.1055/a-1700-1757, 2022)(2023) CHAMMAS, Maria Cristina; TAKAHASHI, Marcelo Straus; MOYSES, Raquel Ajub; POMPEIA, Celine; TAVARES, Marcos Roberto; CERRI, Giovanni Guido
- Focused assessment with sonography for trauma (FAST)(2023) SAVOIA, Paulo; JAYANTHI, Shri; CHAMMAS, MariaThe main cause of death in traumas is hypovolemic shock. Physical examination is limited to detect hemopericardium, hemoperitoneum, and hemopneumothorax. Computed tomography (CT) is the gold standard for traumatic injury evaluation. However, CT is not always available, is more expensive, and there are transportation issues, especially in hemodynamically unstable patients. In this scenario, a rapid, reproducible, portable, and noninvasive method such as ultrasound emerged, directed for detecting hemopericardium, hemoperitoneum, and hemopneumothorax, in a ""point of care"" modality, known as the focused assessment with sonography for trauma (FAST) protocol. With decades of experience, spread worldwide, and recommended by the most prestigious trauma care guidelines, FAST is a bedside ultrasound to be performed when accessing circulation issues of trauma patients. It is indicated to hemodynamically unstable patients with blunt abdominal trauma, with penetrating trauma of the thoracoabdominal transition (where there is doubt of penetrating the abdominal cavity) and for any patient with the cause of the instability unknown. There are four regions to be examined in the traditional FAST protocol: pericardium (to detect cardiac tamponade), right upper abdominal quadrant, left upper abdominal quadrant, and pelvis (to detect hemoperitoneum). The called extended FAST (e-FAST) protocol also searches the pleural spaces for hemothorax and pneumothorax. It is important to know the false positives and false negatives of the protocol, as well as its limitations. FAST/e-FAST protocol is designed to provide a simple ""yes or no"" answer regarding the presence of bleeding. It is not intended to quantify the bleeding nor evaluate organ lesions due to its limited accuracy for these purposes. Moreover, the amount of bleeding and/or the identification of organ lesions will not change patient's management: Hemodynamically unstable patients with positive FAST must go to the operating room without delay. CT should be considered for hemodynamically stable patients.
- Cryoablation of Benign Thyroid Nodules: Preliminary Experience in 3 Cases(2023) FREITAS, Ricardo Miguel Costa de; VANDERLEI, Felipe Augusto Brasileiro; ROSENFELD, Matheus Gerhard; BORGES, Alessandra de Pinho Pimenta; KOWALSKI, Luiz Paulo; CHAMMAS, Maria Cristina