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
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- Color Duplex Doppler US can Follow up the Response of Radioiodine in Graves' Disease by Evaluating the Thyroid Volume and Peak Systolic Velocity(2020) SANTOS, Thiago Adler Ralho Rodrigues; MARUI, Suemi; WATANABE, Tomoco; LIMA, Nicolau; OZAKI, Claudia Okanobo; CERRI, Giovanni Guido; CHAMMAS, Maria C.Purpose The objective of this study was to prove the efficacy of Doppler ultrasonography (US-Doppler) in the follow-up of patients with GD treated with radioactive iodine. Methods 97 patients (77 female and 20 male) with a mean age of 42 years (SD +/- 15) and with prior diagnosis of GD were treated with radioiodine. In total, 88.5 % achieved euthyroidism or hypothyroidism after treatment. The study was documented before treatment and one, three, and six months after treatment with radioactive iodine (131I) by a single investigator. The volume, echogenicity, echotexture and vascularization of the glands as well as the peak systolic velocity (PSV) of the inferior thyroid arteries were evaluated and compared with the laboratory data. Results Thyroid volume and PSV had a statistically significant correlation with hormone levels (p < 0.05). The mean pre-dose therapeutic thyroid volume was 43.01 +/- 3.88 cm(3) and was 11.58 +/- 11.26 cm(3) 6 months after treatment. The mean PSV before 131I was 90.06 +/- 44.13 cm/s and decreased significantly over time (p < 0.001). Six months after the therapeutic dose, the mean PSV was 32.95 +/- 16.36 cm/s. However, the subjective parameters did not have a significant correlation with the normalization of the thyroid hormones. Conclusion Doppler US was useful for monitoring the therapeutic response of GD patients after treatment with radioiodine by evaluating the thyroid volume and peak systolic velocity.
- Evaluation of Parotid Salivary Gland Echo Texture by Ultrasound Examinations and Correlation With Whole-Body Scintigraphy After Radioiodine Therapy in Patients With Differentiated Thyroid Carcinoma(2020) LIMA, Graziele Aparecida Simoes; LOPEZ, Rossana Veronica Mendoza; FREITAS, Ricardo Miguel Costa de; WILLEGAIGNON, Jose; SAPIENZA, Marcelo Tatit; CHAMMAS, Maria Christina; COURA-FILHO, George BarberioObjectives This study aimed to evaluate the echo texture of the parotid salivary glands before and after radioiodine therapy (RIT) using ultrasound (US) images in patients with differentiated thyroid cancer and to evaluate the correlations between post-RIT whole-body scintigraphy (WBS) images and US image patterns in salivary and cervical areas. Methods A retrospective study was performed with data on demographic and clinical information, US examinations, and WBS images collected through medical recordings. Results Comparing the US features before and after RIT, significant echo texture heterogeneity was found in 31.3% of all patients evaluated. When evaluated according to the level of iodine 131 (I-131) radioactivity (<5.6, 5.6-<9.3, and >= 9.3 GBq), echo texture heterogeneity was significantly associated with the 5.6-GBq I-131 radioactivity group (P < .001). No association was found for any level of I-131 post-RIT WBS uptake intensity and changes in US feature patterns. Conclusions Ultrasound may be a useful tool for evaluating chronic sialadenitis after RIT, and the I-131 uptake intensity using a routine post-RIT WBS is not associated with US echo texture changes.
- Ultrasound elastography in patients with fatty liver disease(2020) SILVA, Luiza de Campos Moreira da; OLIVEIRA, Julia Teixeira de; TOCHETTO, Sandra; OLIVEIRA, Claudia Pinto Marques Souza de; SIGRIST, Rosa; CHAMMAS, Maria CristinaAbstract Hepatic steatosis, or fatty liver disease, occurs due to the accumulation of lipids in hepatocytes. When it becomes chronic, lobular inflammation develops and the disease can evolve to hepatic fibrosis, liver cirrhosis, or hepatocellular carcinoma. Early diagnosis is desirable because patients diagnosed in the early stage of the disease respond better to treatment. In the early stages of fatty liver disease, the physical examination is often unremarkable. Fatty liver disease and hepatic fibrosis can be diagnosed and monitored through laboratory tests, imaging, and biopsy. Among the imaging methods, ultrasound stands out as an effective means of diagnosing and following patients with liver disease. Ultrasound used in conjunction with elastography (ultrasound elastography) has recently shown great utility in the follow-up of such patients. Ultrasound elastography studies the degree of deformation (stiffness) of an organ or lesion, so that when there is hardening, fibrosis, or cirrhosis of the liver, those alterations are well demonstrated. In this review article, we discuss the application of the different types of ultrasound elastography for liver studies: transient elastography, point shear wave elastography, and two-dimensional shear wave elastography. Although magnetic resonance elastography may also be used in the analysis of liver fibrosis, it will not be addressed in this article.
- GUIDELINES AND GOOD CLINICAL PRACTICE RECOMMENDATIONS FOR CONTRAST-ENHANCED ULTRASOUND (CEUS) IN THE LIVER-UPDATE 2020 WFUMB IN COOPERATION WITH EFSUMB, AFSUMB, AIUM, AND FLAUS(2020) DIETRICH, Christoph F.; NOLSOE, Christian Pallson; BARR, Richard G.; BERZIGOTTI, Annalisa; BURNS, Peter N.; CANTISANI, Vito; CHAMMAS, Maria Cristina; CHAUBAL, Nitin; CHOI, Byung Ihn; CLEVERT, Dirk-Andre; CUI, Xinwu; DONG, Yi; D'ONOFRIO, Mirko; FOWLKES, J. Brian; GILJA, Odd Helge; HUANG, Pintong; IGNEE, Andre; JENSSEN, Christian; KONO, Yuko; KUDO, Masatoshi; LASSAU, Nathalie; LEE, Won Jae; LEE, Jae Young; LIANG, Ping; LIM, Adrian; LYSHCHIK, Andrej; MELONI, Maria Franca; CORREAS, Jean Michel; MINAMI, Yasunori; MORIYASU, Fuminori; NICOLAU, Carlos; PISCAGLIA, Fabio; SAFTOIU, Adrian; SIDHU, Paul S.; SPOREA, Ioan; TORZILLI, Guido; XIE, Xiaoyan; ZHENG, RongqinThe present, updated document describes the fourth iteration of recommendations for the hepatic use of contrast-enhanced ultrasound, first initiated in 2004 by the European Federation of Societies for Ultrasound in Medicine and Biology. The previous updated editions of the guidelines reflected changes in the available contrast agents and updated the guidelines not only for hepatic but also for non-hepatic applications. The 2012 guideline requires updating as, previously, the differences in the contrast agents were not precisely described and the differences in contrast phases as well as handling were not clearly indicated. In addition, more evidence has been published for all contrast agents. The update also reflects the most recent developments in contrast agents, including U.S. Food and Drug Administration approval and the extensive Asian experience, to produce a truly international perspective. These guidelines and recommendations provide general advice on the use of ultrasound contrast agents (UCAs) and are intended to create standard protocols for the use and administration of UCAs in liver applications on an international basis to improve the management of patients.
- Ultrasonography Echotexture as a surrogate for Sialadenitis secondary to I-131 Radioiodine Therapy for differentiated Thyroid Cancer: a review and metaanalysis(2020) LIMA, Graziele Aparecida Simoes; LOPEZ, Rossana Veronica Mendoza; OZORIO, Gislaine Aparecida; FREITAS, Ricardo Miguel Costa de; WILLEGAIGNON, Jose; SAPIENZA, Marcelo Tatit; CHAMMAS, Maria Christina; COURA-FILHO, George BarberioTo systematically review and analyze the medical literature to assess ultrasonography echotexture changes in thyroid cancer patients for the detection of chronic sialadenitis caused by radioiodine therapy. Methods: Sources were retrieved from PubMed, Scopus, EMBASE and LILACS through November 2018. All studies that assessed ultrasonographic features before I-131 administration and at 12 months after I-131 administration were selected. After data extraction, statistical analysis was performed by using Stata software. Results: From a total of 435 studies, 4 studies involving 665 patients were considered eligible, and echotexture heterogeneity was found with a significant difference. Conclusions: Ultrasound echotexture may detect chronic sialadenitis secondary to salivary radioiodine therapy.
- Nomograms using a small panel of genes for predicting the diagnosis and aggressiveness of prostate cancer(2020) LEITE, Katia R. M.; ORTEGA, Fabio L.; DAMIANI, Lucas P.; GUIMARAES, Vanessa; VIANA, Nayara; SILVA, Iran A.; REIS, Sabrina T.; PIMENTA, Ruan; ADONIAS, Sanarelly P.; CHAMMAS, Cristina; SROUGI, Miguel; NAHAS, Willian
- Synthetic Elastography Using B-Mode Ultrasound Through a Deep Fully Convolutional Neural Network(2020) WILDEBOER, R. R.; SLOUN, R. J. G. van; MANNAERTS, C. K.; MORAES, P. H.; SALOMON, G.; CHAMMAS, M. C.; WIJKSTRA, H.; MISCHI, M.Shear-wave elastography (SWE) permits local estimation of tissue elasticity, an important imaging marker in biomedicine. This recently developed, advanced technique assesses the speed of a laterally traveling shear wave after an acoustic radiation force push to estimate local Youngs moduli in an operator-independent fashion. In this work, we show how synthetic SWE (sSWE) images can be generated based on conventional B-mode imaging through deep learning. Using side-by-side-view B-mode/SWE images collected in 50 patients with prostate cancer, we show that sSWE images with a pixel-wise mean absolute error of 4.5 0.96 kPa with regard to the original SWE can be generated. Visualization of high-level feature levels through ${t}$ -distributed stochastic neighbor embedding reveals substantial overlap between data from two different scanners. Qualitatively, we examined the use of the sSWE methodology for B-mode images obtained with a scanner without SWE functionality. We also examined the use of this type of network in elasticity imaging in the thyroid. Limitations of the technique reside in the fact that networks have to be retrained for different organs, and that the method requires standardization of the imaging settings and procedure. Future research will be aimed at the development of sSWE as an elasticity-related tissue typing strategy that is solely based on B-mode ultrasound acquisition, and the examination of its clinical utility.
- Lung ultrasound: an additional tool in COVID-19(2020) OLIVEIRA, Rodrigo Ribeiro de; RODRIGUES, Thiago Potrich; SILVA, Paulo Savoia Dias da; GOMES, Andrea Cavalanti; CHAMMAS, Maria CristinaAbstract Lung ultrasound is a well-defined diagnostic modality in the point of care emergency medicine concept. In the context of the coronavirus disease 2019 (COVID-19) pandemic, the lung ultrasound assumed an essential role in this disease, with a valid correlation of the imaging results with computed tomography. Recognize how the diagnostic possibilities of ultrasound in the approach of COVID-19 and its differential diagnoses are fundamental.
- Response to Letter to the Editor: ""Nephrocalcinosis and Nephrolithiasis in X-Linked Hypophosphatemic Rickets: Diagnostic Imaging and Risk Factors""(2020) COLARES NETO, Guido de Paula; YAMAUCHI, Fernando Ide; BARONI, Ronaldo Hueb; BIANCHI, Marco de Andrade; GOMES, Andrea Cavalanti; CHAMMAS, Maria Cristina; MARTIN, Regina Matsunaga
- Audiovisual Sexual Stimulation Improves Diagnostic Accuracy of Penile Doppler Ultrasound in Patients With Erectile Dysfunction(2020) CARNEIRO, Felipe; NASCIMENTO, Bruno; MIRANDA, Eduardo P.; CURY, Jose; CERRI, Giovanni G.; CHAMMAS, Maria CristinaIntroduction: Although penile Doppler ultrasound (PDU) is a useful tool in evaluating erectile dysfunction (ED), an optimal erectile response might be limited because of an increased sympathetic discharge. Audiovisual sexual stimulation (AVSS) has been suggested to help improving PDU performance. Aim: To evaluate the use of AVSS as a tool to improve diagnostic accuracy of PDU studies. Methods: A total of 40 men (mean age: 61.8 +/- 10.2 years) with ED were enrolled. PDU sessions were performed in a randomized fashion as follows: session A under intracavernous injection (ICI) alone and session B under ICI and AVSS with 7-day interval between sessions. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) were measured 5, 10, 15, and 20 minutes after ICI. Main Outcome Measure: Comparisons between PSV, EDV, and RI values were performed with and without AVSS. Univariable and multivariable analyses including clinical and demographic parameters were performed to evaluate predictors of an abnormal PDU. Results: 23 patients performed the first session without AVSS, and 17 performed the first session with AVSS. EDV and RI were better in AVSS session (p = 0.022 and 0.019). PSV was not influenced by AVSS (p = 0.768). The proportion of patients whose diagnosis was changed because of the AVSS was 4 of 40 (10.0%, 95% confidence interval [CI]: 2.8-23.7%). Of 12 patients with venous leak observed on the PDU without AVSS, 3 turned into normal after AVSS (25.0%, 95% CI: 5.5-57.2%). Of 4 men with arterial insufficiency observed on the PDU on ICI alone, 1 became normal after AVSS (25.0%, 95% CI: 0.6-80.6%). International Index of Erectile Function-5 scores were lower in patients with abnormal PDU (6.3 +/- 3.3 vs 12.0 +/- 5.8, p=0.003). On multivariable analysis, DM and International Index of Erectile Function-5 scores were the only independent predictors of abnormal PDU studies. Clinical Implications: False diagnoses of venous leak during PDU with ICI could be a result of an increased adrenergic discharge during the examination. Routine AVSS may be helpful to avoid error in diagnosis. Strength & Limitations: The study has randomized the use of AVSS in different session orders. Only one previously published study has used this strategy to control the accommodation effect in repeat studies, a common source of bias in the PDU literature. The main limitation is the absence of a rigidity assessment and a redosing protocol. Conclusion: Adding AVSS during PDU improves ICI response and may help clinicians evaluate penile hemodynamics more accurately.