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1.
Artigo em Português | LILACS, BNUY, UY-BNMED | ID: biblio-1568769

RESUMO

Apesar de não muito frequente, nos últimos 20 anos, houve um aumento significativo dos relatos sobre rotura do peitoral maior, normalmente associadas à prática de atividade física em que ocorre contração intensa e/ou uso de cargas pesadas exercendo resistência sobre o músculo. Neste relato de caso temos um paciente de 51 anos referindo dor no tórax à direita e no braço direito há 3 dias após tentar consertar o guidão da moto. Apresentava assimetria dos peitorais, perda de força do membro superior direito, dificuldade de movimentação e hematoma. A ressonância magnética demonstrou rotura completa da junção miotendínea do peitoral maior, com tendinopatia com fissuras insercionais e intrasubstanciais infraespinhal e tendinopatia com rotura parcial do tendão subescapular. Foi indicado por médico ortopedista o acompanhamento com o uso de medicação analgésica.


Although not very common, in the last 20 years, there has been a significant increase in reports of rupture of the pectoralis major, normally associated with the practice of physical activity in which intense contraction occurs and/or the use of heavy loads exerting resistance on the muscle. In this case report we have a 51-year-old patient reporting pain in his right chest and right arm for 3 days after trying to fix his motorcycle's handlebars. He had asymmetry of the pectorals, loss of strength in the right upper limb, difficulty moving and hematoma. Magnetic resonance imaging demonstrated complete rupture of the myotendinous junction of the pectoralis major, with tendinopathy with insertional and intrasubstantial infraspinatus fissures and tendinopathy with partial rupture of the subscapularis tendon. An orthopedic doctor recommended follow-up with the use of analgesic medication.


Aunque no es muy común, en los últimos 20 años se ha observado un aumento significativo en los reportes de rotura del pectoral mayor, normalmente asociado a la práctica de actividad física en la que se produce una contracción intensa y/o al uso de cargas pesadas ejerciendo resistencia sobre el mismo. el músculo. En este caso clínico tenemos un paciente de 51 años que refiere dolor en el pecho derecho y en el brazo derecho durante 3 días después de intentar arreglar el manillar de su motocicleta. Presentó asimetría de pectorales, pérdida de fuerza en miembro superior derecho, dificultad de movimiento y hematoma. La resonancia magnética demostró rotura completa de la unión miotendinosa del pectoral mayor, con tendinopatía con fisuras de inserción e intrasustancial del infraespinoso y tendinopatía con rotura parcial del tendón subescapular. Un médico ortopédico recomendó seguimiento con el uso de medicación analgésica.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Músculos Peitorais/lesões , Músculos Peitorais/diagnóstico por imagem , Extremidade Superior/lesões , Extremidade Superior/diagnóstico por imagem , Junção Miotendínea/lesões , Junção Miotendínea/diagnóstico por imagem
2.
Molecules ; 29(15)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39125063

RESUMO

The advancement of traditional sample preparation techniques has brought about miniaturization systems designed to scale down conventional methods and advocate for environmentally friendly analytical approaches. Although often referred to as green analytical strategies, the effectiveness of these methods is intricately linked to the properties of the sorbent utilized. Moreover, to fully embrace implementing these methods, it is crucial to innovate and develop new sorbent or solid phases that enhance the adaptability of miniaturized techniques across various matrices and analytes. Graphene-based materials exhibit remarkable versatility and modification potential, making them ideal sorbents for miniaturized strategies due to their high surface area and functional groups. Their notable adsorption capability and alignment with green synthesis approaches, such as bio-based graphene materials, enable the use of less sorbent and the creation of biodegradable materials, enhancing their eco-friendly aspects towards green analytical practices. Therefore, this study provides an overview of different types of hybrid graphene-based materials as well as their applications in crucial miniaturized techniques, focusing on offline methodologies such as stir bar sorptive extraction (SBSE), microextraction by packed sorbent (MEPS), pipette-tip solid-phase extraction (PT-SPE), disposable pipette extraction (DPX), dispersive micro-solid-phase extraction (d-µ-SPE), and magnetic solid-phase extraction (MSPE).

3.
Int Braz J Urol ; 50(5): 595-604, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39106115

RESUMO

PURPOSE: To validate the Barcelona magnetic resonance imaging predictive model (BCN-MRI PM) in men with pre-biopsy multiparametric MRI (mpMRI) reported with the Prostate Imaging Reporting and Data System (PI-RADS) v2.1, followed by transrectal and transperineal prostate biopsies. MATERIALS AND METHODS: Prospective analysis of 3,264 men with PSA >3.0 ng/mL and/or abnormal digital rectal examination who were referred to ten participant centers in the csPCa early detection program of Catalonia (Spain), between 2021 and 2023. MpMRI was reported with the PI-RADS v2.1, and 2- to 4-core MRI-transrectal ultrasound (TRUS) fusion-targeted biopsy of suspected lesions and/or 12-core systematic biopsy were conducted. 2,295 (70.3%) individuals were referred to six centers for transrectal prostate biopsies, while 969 (39.7%) were referred to four centers for transperineal prostate biopsies. CsPCa was classified whenever the International Society of Urologic Pathology grade group was 2 or higher. RESULTS: CsPCa was detected in 41% of transrectal prostate biopsies and in 45.9% of transperineal prostate biopsies (p < 0.016). Both BCN-MRI PM calibration curves were within the ideal correlation between predicted and observed csPCa. Areas under the curve and 95% confidence intervals were 0.847 (0.830-0.857) and 0.830 (0.823-0.855), respectively (p = 0.346). Specificities corresponding to 95% sensitivity were 37.6 and 36.8%, respectively (p = 0.387). The Net benefit of the BCN-MRI PM was similar with both biopsy methods. CONCLUSIONS: The BCN-MRI PM has been successfully validated when mpMRI was reported with the PI-RADS v2.1 and prostate biopsies were conducted via the transrectal and transperineal route.


Assuntos
Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética Multiparamétrica , Próstata , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Estudos Prospectivos , Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Idoso , Pessoa de Meia-Idade , Próstata/patologia , Próstata/diagnóstico por imagem , Períneo/diagnóstico por imagem , Períneo/patologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Imageamento por Ressonância Magnética/métodos
4.
Brain Topogr ; 37(6): 1232-1241, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39162868

RESUMO

The purpose of this study is to evaluate the efficacy of repetitive transcranial magnetic stimulation (rTMS) combined with body weight-support treadmill training (BWSTT) for improving walking function of individuals with chronic incomplete spinal cord injury (iSCI). A 4-week, double-blinded, randomized, sham-controlled pilot study involved 12 sessions of real (10 Hz, 1800 pulses) or sham rTMS combined with BWSTT (15-20 min, moderate intensity). Walking independence was assessed using the Walking Index for Spinal Cord Injury II (WISCI-II). Lower extremity motor function (lower extremity motor score [LEMS]) and spasticity, sensory function, functional independence (Spinal Cord Injury Measure III [SCIM-III]), and quality of life were also assessed. Walking independence (WISCI-II) after the 6th session was higher in the BWSTT/rTMS real (n = 7) (median change (IQR): 3 (1.5 to 3.5)) than in the sham group (n = 8) (median change (IQR): 0 (0 to 0.25), but there was no difference between groups after 12th session (BWSTT/rTMS real median change (IQR): 4 (2 to 5); BWSSTT/rTMS sham median change (IQR): 0 (0 to 3.25). Compared to baseline, LEMS and SCIM-III mobility scores were increased after 12 sessions in the BWSTT/rTMS real but not in the sham group. Within- and between-group sensory function, functional independence, and quality of life remained similar. This preliminary result suggests that combining BWSTT with rTMS could lead to earlier gait improvement in patients with chronic iSCI.


Assuntos
Terapia por Exercício , Traumatismos da Medula Espinal , Estimulação Magnética Transcraniana , Caminhada , Humanos , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/reabilitação , Traumatismos da Medula Espinal/terapia , Projetos Piloto , Masculino , Feminino , Estimulação Magnética Transcraniana/métodos , Caminhada/fisiologia , Pessoa de Meia-Idade , Adulto , Método Duplo-Cego , Terapia por Exercício/métodos , Peso Corporal/fisiologia , Resultado do Tratamento , Qualidade de Vida , Doença Crônica
5.
Radiol Med ; 129(10): 1431-1443, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39106024

RESUMO

PURPOSE: There is an unmet clinical need for non-invasive imaging biomarkers that could replace liver biopsy in the management of patients with autoimmune hepatitis (AIH). In this study, we sought to evaluate the diagnostic accuracy of a simple uncorrected, non-contrast T1 mapping for detecting fibrosis and inflammation in AIH patients using histopathology as a reference standard. MATERIAL AND METHODS: Over 3 years, 33 patients with AIH were prospectively studied using a multiparametric liver MRI protocol which included T1 mapping. Biopsies were performed up to 3 months before imaging, and a standardized histopathological score for fibrosis (F0-F4) and inflammatory activity (PPA0-4) was used as a reference. Statistical analysis included independent t test, Mann-Whitney U-test, and ROC (receiver operating characteristic) analysis. RESULTS: T1 mapping values were significantly higher in patients with advanced fibrosis (F0-2 vs. F3-4; p < 0.015), significant fibrosis (F0-1 vs. F2-4; p < 0.005), and significant inflammatory activity (PPA 0-1 vs. PPA 2-4 p = 0.048). Moreover, the technique demonstrated a good diagnostic performance in detecting significant (AUC 0.856) and advanced fibrosis (AUC 0.835), as well as significant inflammatory activity (AUC 0.763). CONCLUSION: A rapid, simple, uncorrected, non-contrast T1 mapping sequence showed satisfactory diagnostic performance in comparison with histopathology for detecting significant tissue inflammation and fibrosis in AIH patients, being a potential non-invasive imaging biomarker for monitoring disease activity in such individuals.


Assuntos
Hepatite Autoimune , Cirrose Hepática , Imageamento por Ressonância Magnética , Humanos , Hepatite Autoimune/diagnóstico por imagem , Hepatite Autoimune/patologia , Estudos Prospectivos , Feminino , Masculino , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Biópsia , Padrões de Referência , Inflamação/diagnóstico por imagem
6.
Neuroophthalmology ; 48(5): 348-351, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39145323

RESUMO

Arachnoid cysts (ACs) are cerebrospinal fluid collections between the two layers of the normal arachnoid membrane. Although they are often asymptomatic with a stationary course, eventual complications may occur. Herein, we report the case of a 9-year-old boy who developed bilateral papilloedema secondary to spontaneous rupture of an AC in the left middle cranial fossa. Although the papilloedema worsened during follow-up, his visual field remained bilaterally stable, supporting the expectant management and obviating the potential morbidity associated with neurosurgical intervention. This case report highlights the importance of a multidisciplinary approach to patients with secondary intracranial hypertension, including serial ophthalmological examinations, which provide a useful guide to surgical decision-making.

7.
Alzheimers Dement ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136296

RESUMO

BACKGROUND: Education influences brain health and dementia. However, its impact across regions, specifically Latin America (LA) and the United States (US), is unknown. METHODS: A total of 1412 participants comprising controls, patients with Alzheimer's disease (AD), and frontotemporal lobar degeneration (FTLD) from LA and the US were included. We studied the association of education with brain volume and functional connectivity while controlling for imaging quality and variability, age, sex, total intracranial volume (TIV), and recording type. RESULTS: Education influenced brain measures, explaining 24%-98% of the geographical differences. The educational disparities between LA and the US were associated with gray matter volume and connectivity variations, especially in LA and AD patients. Education emerged as a critical factor in classifying aging and dementia across regions. DISCUSSION: The results underscore the impact of education on brain structure and function in LA, highlighting the importance of incorporating educational factors into diagnosing, care, and prevention, and emphasizing the need for global diversity in research. HIGHLIGHTS: Lower education was linked to reduced brain volume and connectivity in healthy controls (HCs), Alzheimer's disease (AD), and frontotemporal lobar degeneration (FTLD). Latin American cohorts have lower educational levels compared to the those in the United States. Educational disparities majorly drive brain health differences between regions. Educational differences were significant in both conditions, but more in AD than FTLD. Education stands as a critical factor in classifying aging and dementia across regions.

8.
Biomed Phys Eng Express ; 10(5)2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39111326

RESUMO

Purpose. To evaluate the feasibility of use of an 1.5 T magnetic resonance (MR)-linear accelerator MR-linac for imaging in gynaecologic high-dose-rate (HDR) brachytherapy.Method. Commissioning measurements for MR images quality control, geometric distortion, dwell position accuracy, applicator reconstruction and end-to-end test for a tandem-and-ring applicator were performed following the recommendations of American Brachytherapy Society, International Commission on Radiation Units and Measurements and Report of the Brachytherapy Working Group of the Spanish Society of Medical Physics. The values for MR-based IGABT were compared to the corresponding values with computed tomography (CT).Results. Measured distorsions for the MR images were less than 0.50 mm compared to the CT images. The differences between 3D displacements for all dwell positions were 0.66 mm and 0.62 mm for the tandem and ring, respectively. The maximum difference is 0.64 mm for the distances from the applicator tip obtained using the films. The CT and MR dose differences for the right and left 'A' points were 0.9% and -0.7%, respectively. Similar results were observed in terms of dose distribution for CT and Mr The gamma passing rate was 99.3% and 99.5%, respectively.Conclusion. The use of MR images from an MR-linac used in a radiotherapy service for gynaecological brachytherapy was proved to be feasible, safe and precise as the geometrical differences were less than 1 mm, and the dosimetric differences were less than 1% when comparing to the use of CT images for the same purpose.


Assuntos
Braquiterapia , Imageamento por Ressonância Magnética , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem , Tomografia Computadorizada por Raios X , Braquiterapia/métodos , Humanos , Feminino , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Radioterapia Guiada por Imagem/métodos , Aceleradores de Partículas , Neoplasias dos Genitais Femininos/radioterapia , Neoplasias dos Genitais Femininos/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodos , Imagens de Fantasmas , Estudos de Viabilidade
9.
Radiol Case Rep ; 19(10): 4151-4157, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39101025

RESUMO

Intraventricular neurocytoma is a low incidence central nervous system tumor. It predominantly affects young adults with no apparent gender predilection. The main symptoms include headache, nausea and vomiting. These result from hydrocephalus due to the obstruction of cerebrospinal fluid flow. On diagnostic imaging, neurocytoma can be suspected by some features, such as peripheral cysts, lobulated contours and septa that bridge the ventricular wall, giving a "scalloped" appearance. There are other characteristics, but they are less specific for the diagnosis. The atypical variant of neurocytoma is even rarer and leads to a worst prognosis. Atypical neurocytomas develop higher proliferative potential identified by the Ki-67 biomarker and higher recurrence rate. There are few studies about the imaging characteristics of atypical neurocytomas. At this point, there are no reliable distinctive features to differentiate atypical neurocytomas, especially due to their low incidence. We present the case of a 20-year-old female patient with symptoms of intracraneal hypertension. CT and MRI of the brain revealed a mass occupying the body of the left lateral ventricle, adjacent to the foramen of Monro. The mass was primarily solid with discrete peripheral cyst and a few scalloped areas. It also showed signs of supratentorial obstructive hydrocephalus. The tumor was partially removed because of bleeding and compromise of vascular structures. Immunohistochemistry revealed positive synaptophysin, elevated Ki-67 (7%), increased number of blood vessels and moderate nuclear atypia. After surgery, the patient persisted with signs of intracranial hypertension, not improving with clinical management and requiring aggressive surgical procedures. While rare, atypical neurocytoma requires a better characterization, especially through imaging, to optimize immediate management and explore new therapeutic options.

10.
ChemMedChem ; : e202400321, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39087920

RESUMO

Hearing loss (HL) affects more than 5% of the global population, with projections indicating an impact of up to 50% on young individuals in the next years. HL treatments remain limited due to the inner ear's hermeticism. HL often involves inflammatory processes, underscoring the need for enhanced delivery of antiinflammatory agents to the inner ear. Our research focuses on the development of a directed therapy based on magnetic nanoparticles (MNPs). We previously synthesized biocompatible folic acid-coated iron oxide-core nanoparticles (MNPs@FA) as potential carriers for the anti-inflammatory Diclofenac (Dfc). This study aims to incorporate Dfc onto MNPs@FA to facilitate targeted drug delivery to the inner ear. Through optimizing the loading procedure, we achieved optimal loading capacity. Dfc release was studied in the simulated target fluid and the administration vehicle. Complete characterization is also shown. In vitro biocompatibility testing ensured the biosafety of the resulting formulation. Subsequent ex vivo targeting assays on murine cochleae validated the nanosystems' ability to penetrate the round window membrane, one of the main HL therapy barriers. These findings serve as validation before continuing to more complex in vivo studies. Together, the data here presented represent an advancement in addressing unmet medical needs in HL therapy.

11.
J Med Case Rep ; 18(1): 386, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39152447

RESUMO

BACKGROUND: Experimental studies have shown that repetitive trans-spinal magnetic stimulation (TsMS) decreases demyelination and enables recovery after spinal cord injury (SCI). However, the usefulness of TsMS in humans with SCI remains unclear. Therefore, the main objective of this study is to evaluate the effects of TsMS combined with kinesiotherapy on SCI symptoms. We describe a protocol treatment with TsMS and kinesiotherapy in a patient with SCI due to neuromyelitis optica (NMO)-associated transverse myelitis. CASE PRESENTATION: A 23-year-old white male with NMO spectrum disorders started symptoms in 2014 and included lumbar pain evolving into a mild loss of strength and sensitivity in both lower limbs. Five months later, the symptoms improved spontaneously, and there were no sensorimotor deficits. Two years later, in 2016, the symptoms recurred with a total loss of strength and sensitivity in both lower limbs. Initially, physiotherapy was provided in 15 sessions with goals of motor-sensory recovery and improving balance and functional mobility. Subsequently, TsMS (10 Hz, 600 pulses, 20-seconds inter-trains interval, at 90% of resting motor threshold of the paravertebral muscle) was applied at the 10th thoracic vertebral spinous process before physiotherapy in 12 sessions. Outcomes were assessed at three time points: prior to physiotherapy alone (T-1), before the first session of TsMS combined with kinesiotherapy (T0), and after 12 sessions of TsMS combined with kinesiotherapy (T1). The patient showed a 25% improvement in walking independence, a 125% improvement in balance, and an 18.8% improvement in functional mobility. The Patient Global Impression of Change Scale assessed the patient's global impression of change as 'much improved'. CONCLUSION: TsMS combined with kinesiotherapy may safely and effectively improve balance, walking independence, and functional mobility of patients with SCI due to NMO-associated transverse myelitis.


Assuntos
Magnetoterapia , Neuromielite Óptica , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal , Humanos , Masculino , Neuromielite Óptica/terapia , Neuromielite Óptica/complicações , Adulto Jovem , Magnetoterapia/métodos , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/reabilitação , Traumatismos da Medula Espinal/terapia , Resultado do Tratamento , Terapia Combinada , Modalidades de Fisioterapia
12.
J Med Phys ; 49(2): 189-202, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39131437

RESUMO

Purpose: This paper explores different machine learning (ML) algorithms for analyzing diffusion nuclear magnetic resonance imaging (dMRI) models when analytical fitting shows restrictions. It reviews various ML techniques for dMRI analysis and evaluates their performance on different b-values range datasets, comparing them with analytical methods. Materials and Methods: After standard fitting for reference, four sets of diffusion-weighted nuclear magnetic resonance images were used to train/test various ML algorithms for prediction of diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), and kurtosis (K). ML classification algorithms, including extra-tree classifier (ETC), logistic regression, C-support vector, extra-gradient boost, and multilayer perceptron (MLP), were used to determine the existence of diffusion parameters (D, D*, f, and K) within single voxels. Regression algorithms, including linear regression, polynomial regression, ridge, lasso, random forest (RF), elastic-net, and support-vector machines, were used to estimate the value of the diffusion parameters. Performance was evaluated using accuracy (ACC), area under the curve (AUC) tests, and cross-validation root mean square error (RMSECV). Computational timing was also assessed. Results: ETC and MLP were the best classifiers, with 94.1% and 91.7%, respectively, for the ACC test and 98.7% and 96.3% for the AUC test. For parameter estimation, RF algorithm yielded the most accurate results The RMSECV percentages were: 8.39% for D, 3.57% for D*, 4.52% for f, and 3.53% for K. After the training phase, the ML methods demonstrated a substantial decrease in computational time, being approximately 232 times faster than the conventional methods. Conclusions: The findings suggest that ML algorithms can enhance the efficiency of dMRI model analysis and offer new perspectives on the microstructural and functional organization of biological tissues. This paper also discusses the limitations and future directions of ML-based dMRI analysis.

13.
Diabetol Metab Syndr ; 16(1): 156, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982515

RESUMO

BACKGROUND: This study investigates myocardial structural changes in stable coronary artery disease (CAD) patients with type 2 diabetes (T2D) using cardiac magnetic resonance (CMR) strain and T1 mapping. METHODS: A total of 155 stable CAD patients underwent CMR examination, including left ventricular (LV) morphology and function assessment, late gadolinium enhancement (LGE), and feature tracking (CMR-FT) for LV global longitudinal, circumferential, and radial strain. T1 mapping with extracellular volume (ECV) evaluation was also performed. RESULTS: Among the enrolled patients, 67 had T2D. Diabetic patients exhibited impaired LV strain and higher ECV compared to non-diabetics. Multivariate analysis identified T2D as an independent predictor of increased ECV and decreased strain. CONCLUSIONS: CMR-based strain and T1 mapping highlighted impaired myocardial contractility, elevated ECV, and potential interstitial fibrosis in diabetic patients with stable CAD. This suggests a significant impact of diabetes on myocardial health beyond CAD, emphasizing the importance of a comprehensive assessment in these individuals. TRIAL REGISTRATION: http://www.controlled-trials.com/ISRCTN09454308.

14.
JACC Case Rep ; 29(14): 102386, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38988439

RESUMO

Chylopericardium is a rare complication after cardiac transplantation. We report a case of a 69-year-old woman with persistent chylopericardium after a heart transplantation due to Chagas disease. Failure of conservative treatment led to dynamic contrast-enhanced magnetic resonance lymphangiography and percutaneous radiologic intervention of the lymphatic leakage and symptoms resolution.

15.
Diagnostics (Basel) ; 14(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39001252

RESUMO

Multiple sclerosis (MS) is the most common acquired inflammatory and demyelinating disease in adults. The conventional diagnostic of MS and the follow-up of inflammatory activity is based on the detection of hyperintense foci in T2 and fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) and lesions with brain-blood barrier (BBB) disruption in the central nervous system (CNS) parenchyma. However, T2/FLAIR hyperintense lesions are not specific to MS and the MS pathology and inflammatory processes go far beyond focal lesions and can be independent of BBB disruption. MRI techniques based on the magnetic susceptibility properties of the tissue, such as T2*, susceptibility-weighted images (SWI), and quantitative susceptibility mapping (QSM) offer tools for advanced MS diagnostic, follow-up, and the assessment of more detailed features of MS dynamic pathology. Susceptibility-weighted techniques are sensitive to the paramagnetic components of biological tissues, such as deoxyhemoglobin. This capability enables the visualization of brain parenchymal veins. Consequently, it presents an opportunity to identify veins within the core of multiple sclerosis (MS) lesions, thereby affirming their venocentric characteristics. This advancement significantly enhances the accuracy of the differential diagnostic process. Another important paramagnetic component in biological tissues is iron. In MS, the dynamic trafficking of iron between different cells, such as oligodendrocytes, astrocytes, and microglia, enables the study of different stages of demyelination and remyelination. Furthermore, the accumulation of iron in activated microglia serves as an indicator of latent inflammatory activity in chronic MS lesions, termed paramagnetic rim lesions (PRLs). PRLs have been correlated with disease progression and degenerative processes, underscoring their significance in MS pathology. This review will elucidate the underlying physical principles of magnetic susceptibility and their implications for the formation and interpretation of T2*, SWI, and QSM sequences. Additionally, it will explore their applications in multiple sclerosis (MS), particularly in detecting the central vein sign (CVS) and PRLs, and assessing iron metabolism. Furthermore, the review will discuss their role in advancing early and precise MS diagnosis and prognostic evaluation, as well as their utility in studying chronic active inflammation and degenerative processes.

16.
Mycoses ; 67(7): e13767, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39004801

RESUMO

BACKGROUND: The radiological manifestations of central nervous system (CNS) cryptococcosis are diverse and often subtle. There is heterogeneity on how different neuroimaging patterns impact prognosis. This study aims to assess the association between the neuroimaging and clinical outcomes of CNS cryptococcosis. METHODS: All patients with CNS cryptococcosis between July 2017 and April 2023 who underwent brain magnetic resonance imaging (MRI) were included. The primary outcome was mortality during hospitalisation. Secondary outcomes were readmission, ventricular shunting, duration of hospitalisation and time to the first negative cerebrospinal fluid culture. We compared the outcomes for each of the five main radiological findings on the brain MRI scan. RESULTS: We included 46 proven CNS cryptococcosis cases. The two main comorbidity groups were HIV infection (20, 43%) and solid organ transplantation (10, 22%), respectively. Thirty-nine patients exhibited at least one radiological abnormality (85%), with the most common being meningeal enhancement (34, 74%). The mortality rates occurred at 11% (5/46) during hospitalisation. We found no significant disparities in mortality related to distinct radiological patterns. The presence of pseudocysts was significantly associated with the need for readmission (p = .027). The ventricular shunting was significantly associated with the presence of pseudocysts (p = .005) and hydrocephalus (p = .044). CONCLUSION: In this study, there is no association between brain MRI findings and mortality. Larger studies are needed to evaluate this important issue.


Assuntos
Criptococose , Imageamento por Ressonância Magnética , Neuroimagem , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Neuroimagem/métodos , Criptococose/diagnóstico por imagem , Criptococose/mortalidade , Criptococose/microbiologia , Adulto , Idoso , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Infecções Fúngicas do Sistema Nervoso Central/diagnóstico por imagem , Infecções Fúngicas do Sistema Nervoso Central/mortalidade , Infecções Fúngicas do Sistema Nervoso Central/microbiologia , Prognóstico , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/mortalidade , Hospitalização , Infecções por HIV/complicações
17.
Small ; : e2402419, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004887

RESUMO

This study focuses on designing and evaluating scaffolds with essential properties for bone regeneration, such as biocompatibility, macroporous geometry, mechanical strength, and magnetic responsiveness. The scaffolds are made using 3D printing with acrylic resin and iron oxides synthesized through solution combustion. Utilizing triply periodic minimal surfaces (TPMS) geometry and mask stereolithography (MSLA) printing, the scaffolds achieve precise geometrical features. The mechanical properties are enhanced through resin curing, and magnetite particles from synthesized nanoparticles and alluvial magnetite are added for magnetic properties. The scaffolds show a balance between stiffness, porosity, and magnetic responsiveness, with maximum compression strength between 4.8 and 9.2 MPa and Young's modulus between 58 and 174 MPa. Magnetic properties such as magnetic coercivity, remanence, and saturation are measured, with the best results from scaffolds containing synthetic iron oxides at 1% weight. The viscosity of the mixtures used for printing is between 350 and 380 mPas, and contact angles between 90° and 110° are achieved. Biocompatibility tests indicate the potential for clinical trials, though further research is needed to understand the impact of magnetic properties on cellular interactions and optimize scaffold design for specific applications. This integrated approach offers a promising avenue for the development of advanced materials capable of promoting enhanced bone regeneration.

18.
Rev Bras Ortop (Sao Paulo) ; 59(Suppl 1): e60-e64, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39027163

RESUMO

Osteolipoma is a rare benign variant of lipoma and constitutes less than 1% of all lipomas, presenting as a well-circumscribed painless mass. It is a tumor known to occur in several regions, usually intraosseous or adjacent to bone tissue, whose pathogenesis is still unclear. Imaging exams are useful in their evaluation and, mainly, in surgical planning, which consists of tumor excision. However, the definitive diagnosis of osteolipoma is made by histopathological examination. Although benign, osteolipomas can compress surrounding structures, leading to important symptomatology, as in this case reported in which it is in contact with the brachial plexus.

19.
Radiol Bras ; 57: e20240004, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39050261

RESUMO

Colorectal cancer is the third most common cancer and the second leading cause of cancer-related death. Rectal cancer accounts for approximately one-third of new colorectal cancer cases, with adenocarcinoma as the predominant subtype. Despite an overall decline in colorectal cancer incidence and mortality, due to advancements in screening, early diagnosis, and treatment options, there is a concerning increase in incidence rates among young patients. Recent significant advances in managing locally advanced rectal cancer, such as the establishment of different surgical approaches, neoadjuvant treatment using different protocols for high-risk cases, and the adoption of organ-preservation strategies, have increased the importance of the role played by radiologists in locoregional assessment on magnetic resonance imaging at baseline, at restaging, and during active surveillance of patients with rectal cancer. In this article, we review the role of restaging rectal magnetic resonance imaging after neoadjuvant therapy, providing radiologists with a practical, step-by-step guide for assessing treatment response.


O câncer colorretal é o terceiro câncer mais comum e a segunda principal causa de morte relacionada ao câncer. O câncer retal representa aproximadamente um terço dos novos casos de câncer colorretal, sendo o adenocarcinoma o subtipo predominante. Apesar de uma diminuição geral na incidência e mortalidade, impulsionada por avanços na prevenção do câncer, diagnóstico precoce e opções de tratamento aprimoradas, há uma preocupante elevação nas taxas entre os pacientes jovens. Avanços recentes significativos no manejo do câncer retal localmente avançado, como abordagens cirúrgicas, o uso de diferentes protocolos de tratamento neoadjuvante para casos de alto risco e a adoção de estratégias de preservação de órgãos, aumentaram o papel dos radiologistas na avaliação locorregional por meio da ressonância magnética na avaliação inicial, reestadiamento e vigilância ativa de pacientes com câncer retal. Este manuscrito tem como objetivo revisar o papel da ressonância magnética retal no reestadiamento após terapia neoadjuvante, fornecendo aos radiologistas um guia prático para revisar exames nesse contexto.

20.
J Imaging ; 10(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39057732

RESUMO

Precise annotations for large medical image datasets can be time-consuming. Additionally, when dealing with volumetric regions of interest, it is typical to apply segmentation techniques on 2D slices, compromising important information for accurately segmenting 3D structures. This study presents a deep learning pipeline that simultaneously tackles both challenges. Firstly, to streamline the annotation process, we employ a semi-automatic segmentation approach using bounding boxes as masks, which is less time-consuming than pixel-level delineation. Subsequently, recursive self-training is utilized to enhance annotation quality. Finally, a 2.5D segmentation technique is adopted, wherein a slice of a volumetric image is segmented using a pseudo-RGB image. The pipeline was applied to segment the carotid artery tree in T1-weighted brain magnetic resonance images. Utilizing 42 volumetric non-contrast T1-weighted brain scans from four datasets, we delineated bounding boxes around the carotid arteries in the axial slices. Pseudo-RGB images were generated from these slices, and recursive segmentation was conducted using a Res-Unet-based neural network architecture. The model's performance was tested on a separate dataset, with ground truth annotations provided by a radiologist. After recursive training, we achieved an Intersection over Union (IoU) score of (0.68 ± 0.08) on the unseen dataset, demonstrating commendable qualitative results.

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