DSpace Collection: Instituto de Radiologia - HC/InRadInstituto de Radiologia - HC/InRadhttps://observatorio.fm.usp.br/handle/OPI/1012024-03-28T16:02:54Z2024-03-28T16:02:54ZStatic and dynamic high-resolution ultrasound analysis of tissue distribution of poly-L-lactic acid particles during subdermal application in two different presentationsCUNHA, M. G. daSIGRIST, R.https://observatorio.fm.usp.br/handle/OPI/586952024-03-25T13:46:13Z2023-01-01T00:00:00ZTitle: Static and dynamic high-resolution ultrasound analysis of tissue distribution of poly-L-lactic acid particles during subdermal application in two different presentations
Authors: CUNHA, M. G. da; SIGRIST, R.
Abstract: Background: All the changes the skin goes through, peaking at flaccidity, occur in the dermis and hypodermis, leading to loss of support and a lower capacity to totally accommodate displacements or any loss of subjacent volume, bringing about the onset of furrows and sagging. Improvements in facial sagging may be obtained with the administrations of substances like poly-L-lactic acid (PLLA), which triggers a tissue response through a controlled inflammatory reaction. Objectives: Compare the tissue distribution of the particles of PLLA of both products available in Brazil (Sculptra® and Rennova Elleva®) during and immediately after their subdermal administrations, with 22G cannulas, through high-resolution ultrasound imaging. Methods: A total of four patients aged between 18 and 64 years had the inner part of the upper arms divided into eight quadrants and treated with 16 ml of each product, reconstituted to correspond to 9.5 mg/ml. The sites where PLLA was injected were analyzed through the high-resolution ultrasound during (dynamic imaging) and immediately after the procedures (static imaging). Results: During Sculptra® injection, high-resolution ultrasound revealed that its distribution did not follow the trajectory of the cannula homogeneously. It was characterized by a more hyperechogenic central portion and an anechogenic peripheral portion, forming discrete posterior acoustic shadowing at times. Regarding Rennova ELLEVA® injection, the high-resolution ultrasound analysis showed a homogeneous distribution of the product across the subcutaneous tissue following the trajectory of the cannula without formation of significant interface with the surrounding tissue, maintaining the sonographic aspect of thinly granulated hyperechogenic deposits, with strong posterior acoustic shadowing during and immediately after its administration. Conclusion: Static and dynamic high-resolution ultrasound imaging show a more homogenous distribution of PLLA particles with the use of Rennova ELLEVA® when compared with Sculptra®, which may induce the formation of capsules and a subsequent more dispersed fibroplasia, with larger area of action and a possible better therapeutic result. The interest of this article lies in its originality, highlighting the differences in the tissue distribution of two different brands of PLLA particles, which can impact the clinical response to the two products - which we are researching and seems to interfere with the increase in dermal thickness.2023-01-01T00:00:00ZThermal measurements of a muscle-mimicking phantom during ultra-high field magnetic resonance imagingGARCIA, M. M.OLIVEIRA, T. R.CHAIM, K. T.OTADUY, M. C. G.BRUNS, C.BERNARDING, J.SVEJDA, J. T.ERNI, D.ZYLKA, W.https://observatorio.fm.usp.br/handle/OPI/586942024-03-25T13:43:52Z2023-01-01T00:00:00ZTitle: Thermal measurements of a muscle-mimicking phantom during ultra-high field magnetic resonance imaging
Authors: GARCIA, M. M.; OLIVEIRA, T. R.; CHAIM, K. T.; OTADUY, M. C. G.; BRUNS, C.; BERNARDING, J.; SVEJDA, J. T.; ERNI, D.; ZYLKA, W.
Abstract: At ultra-high field MRI (Bo>7T) it is crucial to predict and control the patient safety. Commonly patient safety is controlled by the power deposited in the tissue (specific absorption rate - SAR). However, temperature distributions do not always correlate directly with SAR distributions, which makes temperature control also a crucial parameter to guarantee patient safety. In this work, temperature changes were accessed by MR thermometry, specifically by the proton resonance frequency shift technique (PRF). A phantom mimicking muscle tissue was used to evaluate the temperature rise caused by the radiofrequency (RF) absorption during 7T MRI, applied through a commercial birdcage head coil. A pulse-sequence protocol was implemented for both, the generation of temperature increase and the MR thermometry. To control the temperature, a digital thermometer was used, and oil tubes were utilized to dismiss the drift effects for PRF. Measurements of the phantom's dielectric characteristics, i.e. conductivity and permittivity, were in good agreement with the literature values for muscle. Spatio-temporal evaluations showed a temperature increase in time via RF exposure and the feasibility of measuring temperature maps using the PRF shift method. The accuracy of the PRF shift method increased when the drift effects were quantified and dismissed, indicating a PRF reading accuracy differing less than 0.5 °C from the thermometer. Results also validate our heating and temperature imaging protocol. This study is a valuable contribution to the evaluation of heating effects caused by RF absorption and demonstrates potential impact on future thermal investigations, which may use different heating sources, as well validate thermal simulations.2023-01-01T00:00:00ZMultimodality imaging for investigating constrictive pericarditisMORALES, Kevin Rafael De PaulaVAZ, AndreCOUTO, Renata MullerFONSECA, Eduardo Kaiser Ururahy Nuneshttps://observatorio.fm.usp.br/handle/OPI/583252024-02-15T15:03:13Z2023-01-01T00:00:00ZTitle: Multimodality imaging for investigating constrictive pericarditis
Authors: MORALES, Kevin Rafael De Paula; VAZ, Andre; COUTO, Renata Muller; FONSECA, Eduardo Kaiser Ururahy Nunes2023-01-01T00:00:00ZAdvances in diffuse glial tumors diagnosisGODOY, Luis Filipe de SouzaPAES, Vitor RibeiroAYRES, Aline SgnolfBANDEIRA, Gabriela AlencarMORENO, Raquel AndradeHIRATA, Fabiana de Campos CordeiroSILVA, Frederico Adolfo BenevidesNASCIMENTO, FelipeCAMPOS NETO, Guilherme de CarvalhoGENTIL, Andre FelixLUCATO, Leandro TavaresAMARO JUNIOR, EdsonYOUNG, Robert J.MALHEIROS, Suzana Maria Fleuryhttps://observatorio.fm.usp.br/handle/OPI/582802024-02-15T14:57:55Z2023-01-01T00:00:00ZTitle: Advances in diffuse glial tumors diagnosis
Authors: GODOY, Luis Filipe de Souza; PAES, Vitor Ribeiro; AYRES, Aline Sgnolf; BANDEIRA, Gabriela Alencar; MORENO, Raquel Andrade; HIRATA, Fabiana de Campos Cordeiro; SILVA, Frederico Adolfo Benevides; NASCIMENTO, Felipe; CAMPOS NETO, Guilherme de Carvalho; GENTIL, Andre Felix; LUCATO, Leandro Tavares; AMARO JUNIOR, Edson; YOUNG, Robert J.; MALHEIROS, Suzana Maria Fleury
Abstract: In recent decades, there have been significant advances in the diagnosis of diffuse gliomas, driven by the integration of novel technologies. These advancements have deepened our understanding of tumor oncogenesis, enabling a more refined stratification of the biological behavior of these neoplasms. This progress culminated in the fifth edition of the WHO classification of central nervous system (CNS) tumors in 2021. This comprehensive review article aims to elucidate these advances within a multidisciplinary framework, contextualized within the backdrop of the new classification. This article will explore morphologic pathology and molecular/genetics techniques (immunohistochemistry, genetic sequencing, and methylation profiling), which are pivotal in diagnosis, besides the correlation of structural neuroimaging radiophenotypes to pathology and genetics. It briefly reviews the usefulness of tractography and functional neuroimaging in surgical planning. Additionally, the article addresses the value of other functional imaging techniques such as perfusion MRI, spectroscopy, and nuclear medicine in distinguishing tumor progression from treatment-related changes. Furthermore, it discusses the advantages of evolving diagnostic techniques in classifying these tumors, as well as their limitations in terms of availability and utilization. Moreover, the expanding domains of data processing, artificial intelligence, radiomics, and radiogenomics hold great promise and may soon exert a substantial influence on glioma diagnosis. These innovative technologies have the potential to revolutionize our approach to these tumors. Ultimately, this review underscores the fundamental importance of multidisciplinary collaboration in employing recent diagnostic advancements, thereby hoping to translate them into improved quality of life and extended survival for glioma patients.2023-01-01T00:00:00Z