Navegando por Palavras-chave "Magnetic Resonance"
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- ItemSomente MetadadadosAdenomas hipofisários: relação entre achados de imagem na Ressonância Magnética (RM), consistência cirúrgica e anatomia patológica(Universidade Federal de São Paulo (UNIFESP), 2021) Gaia, Felipe Franco Pinheiro [UNIFESP]; Cruz, Oswaldo Laercio Mendonca [UNIFESP]; Universidade Federal de São PauloIntroduction: Trans-sphenoid surgery for pituitary adenomas is the most frequent option for the treatment of these tumors today. The intraoperative difficulty in this technique depends a lot on the consistency of the tumor and the literature does not provide clear subsidies for the measurement of tumor consistency in preoperative planning and, consequently, on the degree of surgical difficulty. Objective: To perform a comprehensive literature review on pituitary adenomas and their consistency assessed by magnetic resonance imaging, intraoperative consistency and their correlation with histopathology (collagen and reticulin). Based on the results obtained in this review, to develop a prospective study in an attempt to establish an imaging study protocol that can safely predict tumor consistency prior to surgery. Methods: Literature review through the Medline database. In parallel, from November 2017 to July 2019, prospectively studied patients diagnosed with pituitary adenoma who underwent surgical resection by trans-sphenoidal endoscopy. A total of 15 patients were operated on, 5 of wich were used to exemplify the method. All patients underwent magnetic resonance imaging, intraoperative consistency and collagen and reticulin quantification by fractal analysis. Results: Literature data are still insufficient to define if there was a relationship between imaging findings and tumor consistency, predicting the degree of intraoperative difficulty. Five surgical cases studied provided the definition and validation of a magnetic resonance study protocol for this purpose. Conclusion: There is not yet in literature an imaging protocol capable of reliably predicting the consistency of pituitary adenomas. Thus, through the analysis of Imaging (MRI), Surgery and Histopathology data, we propose an MRI imaging protocol in an attempt to reduce bias and better predict tumor consistency prior to surgery.
- ItemSomente MetadadadosAvaliação do globo ocular nos exames de imagem de rotina: o que o radiologista precisa saber(Universidade Federal de São Paulo (UNIFESP), 2019-09-26) Pfluck, Barbara Pena Mujica [UNIFESP]; Abdala, Nitamar [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objective: To discuss ocular imaging patterns of prevalent intraocular lesions and incidental findings on computed tomography and magnetic resonance. Furthermore, by a comprehensive anatomical review of ocular globe, it intends to provide a systematic radiological approach and prompt identification of a range of imaging features. Methods: This study was classified as a Pictorial Review. The electronic medical record was also reviewed to determine the subsequent management, pathology results and outcome of clinical and radiologic follow-up. Discussion: Radiologists are routinely exposed to a spectrum of different imaging features involving the globe, including expected and incidentally discovered ocular pathologies. Beyond that, there is a range of ophthalmologic procedures, which can alter the normal ocular anatomy image. Fortunately, there are characteristic findings that enable the correct diagnosis. Conclusion: Familiarity with the image patterns of common ocular abnormalities is crucial to radiologists. The ability to recognize these conditions is critical for accurate radiological interpretation and to prevent unnecessary further follow-up. Knowledge of the relevant anatomy of the ocular globe allows a systematic approach to assessing the ocular injuries and help craft the appropriate differential diagnosis.
- ItemSomente MetadadadosDesenvolvimento do ligamento cruzado anterior e fossa intercondilar na população pediátrica: estudo por ressonância magnética(Universidade Federal de São Paulo (UNIFESP), 2020-10-15) Lima, Fernando Mesquita [UNIFESP]; Fernandes, Artur Da Rocha Correa [UNIFESP]; Universidade Federal de São PauloPurpose: To evaluate the characteristics of development of the anterior cruciate ligament (ACL) and intercondylar notch in the pediatric population with magnetic resonance imaging, emphasizing the differences between males and females. Methods: In this retrospective study, musculoskeletal radiologists evaluated length, area, coronal and sagittal inclination of the ACL, inclination of the intercondylar notch, intercondylar notch width, bicondylar distance and notch width index (NWI). A total of 253 MR examinations (130 males and 123 females between 6 and 18 years of age) were included. The association between measurements, sex and age was considered. Linear and fractional polynomial regression models were used to evaluate the relationships between measurements. Results: ACL Length showed significant progressive growth (p<0.001) with age in both sexes, without characterization of growth peaks. ACL Area in female showed more pronounced growth up to 11 years, stabilized from 11 to 14 years and then sustained a slight reduction. In male, ACL Area showed more pronounced growth up to 12 years, stabilized from 12 to 14 years and then sustained slight reduction. Coronal and sagittal inclination of the ACL showed a significant progressive increase (p<0.001) with age in both sexes, progressively verticalizing. The intercondylar roof inclination angle showed significant progressive reduction (p<0.001) with age in both sexes. Intercondylar notch width increased up to 10 years of age in females and 11 years of age in males, with relative stabilization up to 13 years in girls and 14 years in boys and a slight reduction in values at subsequent ages. Bicondylar distance showed significant progressive growth with age in both sexes. NWI showed a discrete and homogenous reduction with age in both sexes. Conclusion: The ACL area and the intercondylar notch width show a similar development pattern, interrupting its growth around 10—11 years of age in female and 11—12 years of age in males, with relative stabilization up to 13—14 years and a slight reduction in dimensions in subsequent ages. The ACL area does not accompany skeletal maturation or its longitudinal growth, interrupting its growth around 11—12 years. We also observed progressive verticalization of the ACL as well as of the intercondylar notch roof in the evaluated ages.
- ItemAcesso aberto (Open Access)Doença cerebrovascular em pacientes com síndrome do anticorpo antifosfolípide: avaliação pelo Doppler transcraniano e ressonância magnética(Universidade Federal de São Paulo (UNIFESP), 2019-06-27) Ricarte, Irapua Ferreira [UNIFESP]; Silva, Gisele Sampaio [UNIFESP]; Dutra, Lívia Almeida [UNIFESP]; http://lattes.cnpq.br/2916631594056232; http://lattes.cnpq.br/6812788681744190; http://lattes.cnpq.br/6623012368578821; Universidade Federal de São Paulo (UNIFESP)Introduction: The potential mechanisms by which a patient with antiphospholipid antibody syndrome (APS) can present with cerebrovascular disease are numerous, including in situ thrombosis and embolism from distant sites. Transcranial Doppler (TCD) may be a useful tool in the evaluation of patients with APS, helping to stratify the risk of cerebrovascular ischemic events in this population. The characteristics of the TCD examination and its correlations with neuroimaging tests in patients with APS had not been previously systematically evaluated. Objectives: To describe the following characteristics of TCD examination: frequency of microembolic signal (MES), frequency of right-left shunt (RLS), presence of intracranial stenosis and cerebral vasomotor reactivity in a group of patients with primary APS (PAPS) and secondary APS (SAPS) in comparison with patients with systemic lupus erythematosus (SLE) and healthy volunteers; to determine the frequency of abnormalities on brain magnetic resonance imaging (MRI) of the studied patients and to correlate these abnormalities with TCD findings; to evaluate the association between history of cerebrovascular disease and TCD findings. Methods: This was a cross-sectional study that evaluated consecutive adult patients with the diagnosis of APS (primary and secondary) comparing with a group of patients with SLE and healthy controls matched by age and sex. All patients with adequate acoustic window were evaluated with a standardized TCD protocol performed by the same neurologist, including: basic exam with evaluation of mean velocities and pulsatility indexes of the intracranial arteries; assessment of cerebral vasoreactivity through the apnea test and microbubble test for RLS detection. After TCD examination, the patients underwent brain MRI. Results: A total of 94 subjects were included in the study (27 patients with SLE, 24 patients with PAPS, 22 patients with SAPS and 21 controls). MES were more frequently found in patients with SLE when compared to controls and patients with APS (PAPS: 4.3%, SAPS: 0%, SLE: 17.4%, controles: 0%, p=0.03). Patients with APS had a higher frequency of RLS when compared to volunteers (63.6% versus 38.1%, p=0.05). Breath holding index (BHI) values tended to be lower in patients with SAPS than in control subjects and patients with PAPS and SLE (p=0.06). Brain MRI findings were similar between the groups, except for the frequency of lacunar infarction, which was higher in patients with SAPS (p = 0.022). Patients with intracranial stenosis detected by TCD had a higher frequency of territorial infarction (40% versus 7.5%, p = 0.02), lacunar infarction (40% versus 11.3%, p=0.075) and borderzone infarction (20% versus 1.9%, p=0.034). Conclusions: Patients with SLE had a higher frequency of MES than patients with APS and healthy controls, which may suggest an effect of anticoagulant therapy used in patients with APS. Patients with APS had a higher frequency of RLS when compared to the control group, which alerts for the need of cardiological investigation in patients with APS and cerebrovascular disease. The frequency of abnormalities in brain MRI was similar between groups, except for the frequency of lacunar infarction. Patients with intracranial stenosis detected by TCD presented a higher frequency of territorial, lacunar and borderzone infarcts, suggesting that the evaluation of the intracranial vasculature should not be neglected in patients with APS and stroke. Key words: antiphospholipid syndrome, transcranial Doppler, microembolic signal, stroke, magnetic resonance, intracranial stenosis, right-left shunt. Methods: This was a cross – sectional study that evaluated consecutive adult patients with the diagnosis of APS (primary and secondary) comparing with a group of patients with SLE and healthy controls matched by age and sex. All patients with adequate acoustic window were evaluated with a standardized TCD protocol performed by the same neurologist, including: basic exam with evaluation of mean velocities and pulsatility indexes of the intracranial arteries; assessment of cerebral vasoreactivity through the apnea test and microbubble test for RLS detection. After TCD examination, the patients underwent brain MRI.
- ItemSomente MetadadadosEstudo das alterações radiográficas e de ressonância magnética relacionadas à lesão da placa plantar metatarsofalângica do segundo pododáctilo(Universidade Federal de São Paulo (UNIFESP), 2020-07-02) Mann, Tania Szejnfeld [UNIFESP]; Fernandes, Eloy De Avila [UNIFESP]; Universidade Federal de São PauloObjective: To investigate whether the protrusion measurements of the second metatarsal, performed using Coughlin’s method, on radiographs and MRI images are related and reproducible. Check if the greater relative length of the second metatarsal is associated with metatarsophalangeal plantar plate lesion. Evaluate, through forefoot MRI, the prevalence of degenerative lesions of the plantar plate of the 2nd metatarsophalangeal joint in individuals with metatarsalgia and describe its main characteristics in MRI. Methods: Radiographic images of the feet with load and forefoot MRI of 166 consecutive patients (211 feet) were retrospectively evaluated. Two independent observers measured the protrusion of the second metatarsus using Coughlin’s method. Using MRI images, the plantar plate of the second toe was independently assessed by the observers, and classified as normal, complete rupture or degenerative lesion. Results: The measurements of the second metatarsal protrusion performed by the two observers showed almost perfect correlation (r = 0.882), however, it was found that the measurements obtained on the radiograph are approximately 35% greater than those obtained on MRI. There was a statistical difference in the measure of protrusion of the second metatarsal between the normal and ruptured groups. Using a ROC curve, it was possible to determine that the protrusion of 5.47 mm, measured on radiography, or 3.14 mm, on MRI, is associated with plantar plate lesion. Degenerative lesion of the plantar plate, identified on MRI as a heterogeneous thickening or thinning of the plantar plate, was best observed in coronal intermediate-weighted sequences, and recorded in 24% of our sample. The presence of pericapsular fibrosis below the transverse intermetatarsal ligament is an indirect finding related to this lesion. Conclusion: We found that the protrusion measurements of the second metatarsal, performed using Coughlin’s method on radiographs and MRI, are related and reproducible, considering that this measure is 35% lower in MRI than radiography. It was also verified that the protrusion of the second metatarsal is a factor that favors the lesion of the metatarsophalangeal plantar plate of the second toe. Degenerative lesions of the plantar plate were identified in a quarter of our sample, being best seen in coronal intermediate-weighted images, and pericapsular fibrosis below the transverse intermetatarsal ligament, best visualized in T1-weighted coronal-short axis, was the indirect finding that most related to this injury.
- ItemSomente MetadadadosA performance da ressonância magnética como teste diagnóstico adicional na avaliação de calcificações mamográficas suspeitas(Universidade Federal de São Paulo (UNIFESP), 2019-09-05) Ninno, Andrea Alves Maciel Di [UNIFESP]; Lederman, Henrique Manoel [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objectives: To evaluate magnetic resonance (MRI) performance indicators as an additional method in the study of suspicious mammographic calcifications, identifying the enhancement patterns most related to malignancy and aggressiveness of carcinoma in situ. Methods: A prospective longitudinal study including 162 patients, whose mammographic screening exams showed suspicious calcifications clusters, categories 4 and 5 according to the system of BI-RADS® categorization. All patients underwent anatomopathological correlation and magnetic resonance of the breast, performed between January 2011 and July 2015 and the histological results were related to the presence and patterns of enhancement. Results: All 162 were female patients, mean age of 53 years old (34 to 82 years old) with 163 mammographic lesions. The anatomopathological biopsy results included 77/163 (47.2%) benign lesions, 64/163 (39.3%) malignant lesions and 22/163 (13.5%) precursor lesions. Benign lesions manifested enhancement in 17/77 (22.1%), malignant lesions in 56/64 (87.5%) and precursor lesions in 5/22 (22.7%). Malignant lesions were more associated with the presence of enhancement and benign lesions with the absence of it, with statistically significant results. The sensitivity, specificity and resonance accuracy values, PPV and NPV in evaluation of calcifications by MRI were 87.5%, 77.8%, 81.5%, respectively. Twenty two of 163 (13.5%) cases were PF and eight of 163 (5%) cases of NF were observed. Malignant lesions showed only suspicious enhancement 56/56 (100%), with predominance of non-nodular pattern in 38/56 (67.9%) and clumped segmental in 28/56 (50%) of the cases. In relation to in situ carcinomas we observed enhancement in 30/38 (78.9%) of the cases. High-grade DCIS exhibited enhancement in the majority 24/26 (92.3%) with a predominance of non-nodular enhancement in 17/23 (73.9%). Conclusions: MRI can be considered as an additional method for evaluating suspected mammographic calcifications, increasing specificity and PPV in comparison with mammography, especially when it presents clumped segmental enhancement. The presence of enhancement in DCIS showed a high association with high-grade lesions.
- ItemSomente MetadadadosRessonância Magnética Com Contraste Dinâmico Como Ferramenta Complementar Para A Avaliação De Calcificações Bi-Rads 4(Universidade Federal de São Paulo (UNIFESP), 2017-11-30) Zacarias, Marina Silva [UNIFESP]; Lederman, Henrique Manoel [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Breast cancer is the second most common neoplasm in the world among women, with an average estimate of 22% of new cases each year. According to the National Institute of Cancer José Alencar Gomes da Silva (INCA), the estimate for 2014 is 57120 new cases with 13345 deaths, 13225 women and 120 men (1). Due to the limitations in the primary prevention of breast cancer applicable to the population in general, the technological advances have been directed to its early diagnosis, once that in the early stages or in the noninvasive form, this disease has a good chance of cure, with a 5-year survival rate of 98% (2). As a result, tracking programs have emerged, the main role of which is to reduction of breast cancer mortality through the detection of early-stage cancer in asymptomatic women, ie without clinical signs that can be detected in self-examination or clinical examination. As a secondary result, there is an increase in survival due to the disease and reduction of surgical treatment extension, allowing less mutilating surgeries, as well as as reducing the need for chemotherapy (3). Despite the significant increase in the number of new cases both in developed countries, mortality rates are in decline in populations under regular programs of screening (4,5). These programs chose to adopt mammography as the method of which is considered the most sensitive method to detect breast cancer in the pre-clinical phase (6). The most important mammographic finding for screening is calcification. She may represent the only sign of malignancy, the first finding being in about 70% of ductal carcinomas in situ (DCIS) detected in screening tests (7). Histologically, these represent intraductal calcifications in areas of necrotic tumor or calcifications mucin secreting tumors, such as the cribriform or micropapillary subtype of intraductal cancer (8-10). The radiological appearance of suspected calcifications includes amorphous, coarse and heterogenous and fine pleomorphic with or without a linear branching pattern (2,7,8). Branched linear calcifications have a higher predictive value for malignancy than nonlinear calcifications, especially for high grade DCIS. Unfortunately, cancer of the breast, including CDIS, most often presents as granular, overlapping 6 with benign findings, which reduces the specificity of mammography (10% to 60%) and results in in the detection of a large number of calcifications that require a complementary examination (7,10). The mammographic aspect just can not differentiate between breast cancers invasive ductal carcinomas, because there is no invasion of the basement membrane. In addition, the method may be limited in the assessment of the extension of the disease, due to areas of the tumor without calcification in the interior (11,12). Due to the fact that some areas of these tumors are not calcified, several studies report changes in therapeutic planning in 11% to 15% of cases when mammography to another imaging method, evidencing additional foci of malignancy not detectable mammographically in about 27% to 34% of the cases (4,11,13). In this scenario, magnetic resonance imaging (MRI) complement the mammographic evaluation (11,13,14). Recent studies have shown that the magnetic resonance imaging of the breast with intravenous contrast injection has sensitivity exceptional for the diagnosis of invasive carcinoma (88% - 100%) (13,15,16). For another To date, there has been no agreement on the sensitivity and specificity of magnetic resonance imaging for the detection of CDIS; although cases of DCIS detected only in MRI have been reported, the role of magnetic resonance imaging in the characterization of suspect calcifications remains a controversial subject (13,17).
- ItemAcesso aberto (Open Access)Ressonância magnética de corpo total com sequência de difusão e FDG-PET/TC: estudo de correlação na avaliação do Linfoma de Hodgkin em crianças, adolescentes e adultos jovens(Universidade Federal de São Paulo (UNIFESP), 2019-07-04) Schiavon, Jose Luiz De Oliveira [UNIFESP]; Lederman, Henrique Manoel [UNIFESP]; Ragazzini, Rodrigo [UNIFESP]; http://lattes.cnpq.br/1192557620651923; http://lattes.cnpq.br/6102707812313296; http://lattes.cnpq.br/2987887118534856; Universidade Federal de São Paulo (UNIFESP)Objective: Correlate the use of WB-MRI/DWI and FDG-PET/CT on children, adolescents and young adults Hodgkin Lymphoma patients, evaluating if it can be used as an alternative to ionizing radiation exams, on Hodgkin Lymphoma (HL) protocols, during staging and follow-up. Materials and methods: 33 studies from 20 HL patients from our institute, aged from 6 to 20 years old, that had both WB-MRI/DWI and FDG-PET/CT images, during a maximum of 21 day-period between acquiring those methods, were read in consensus by 2 pediatric radiologists, and classified by the presence and major extension of HL on 19 different regions. Results: The mean patients’ ages were 15.6 years old. 24.2% were staging examinations and 75.8% follow-up. The mean time between acquisitions from both methods was 7.6 days. Pearson´s (-1 to 1) correlation found r=0,831 (p<0,001) for the number of positive sites and r=0,863 (p <0,001) for their major measurements, demonstrating a statistically significant and strong positive correlation. Kappa correlation found considering FDG-PET/TC as standard was 0.08004. Conclusion: WBMRI-DWI is a safe and reliable method, with very strong Pearson correlation and almost perfect Kappa, that can be used as an alternative to FDG-PET/CT on childhood, adolescent, and young adults Hodgkin lymphoma care, helping reduce later radiation toxicity.
- ItemAcesso aberto (Open Access)Utilização da técnica de realce por manganês em ressonância magnética no estudo da epilepsia induzida por pilocarpina(Universidade Federal de São Paulo (UNIFESP), 2010-04-28) Malheiros, Jackeline Moraes [UNIFESP]; Covolan, Luciene [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Recently, there is renewed interest in combining MRI relaxation effects of Mn2+ in temporal lobe epilepsy (TLE) models. Manganese-enhanced magnetic resonance imaging (MEMRI) could act as surrogate marker of calcium influx into cells and trace neuronal connections, suggesting that it can act as imaging marker of epileptic focus. The aim of this study was to investigate changes in the manganese enhanced contrast evaluated by image acquisitions in the acute and chronic phases of the pilocarpine model of TLE. At the acute phase, the MEMRI signal intensity was analyzed at three different time points after the beginning of SE (Status epilepticus): 5, 15 or 30 minutes. The SE 30 minutes group diminished MEMRI signal intensity in CA1 and dentate gyrus (DG). There were no differences between control and the other groups. The c-fos expression accessed in the same animals indicated that 5 minutes of SE is sufficient to cause maximal cellular activity. At the chronic phase of pilocarpine model, the aim was to compare the mossy fiber sprouting (MFS) and the MEMRI hiperintensity in dentate gyrus (DG) in animals co-treated with cycloheximide (CHX). The co-administration of the protein synthesis inhibitor CHX blocked the MFS in some animals and did not prevent subsequent epileptogenesis. The results indicate a strong correlation between MFS and MEMRI hiperintensity for CHX+pilocarpine group (r=0,864) as well as for pilocarpine and control groups (r=0,78). The results are in agreement with the proposal that MEMRI hiperintensity are correlated to MFS in chronic model of TLE, even in CHX+pilocapine-treated animals.