ABSTRACT
OBJECTIVE: To evaluate the association between shear wave elastography parameters and arterial resistance in kidney transplant recipients. MATERIALS AND METHODS: This was a prospective cross-sectional study involving consecutive adult kidney transplant recipients. All patients underwent color Doppler to evaluate the resistive index (RI) and ultrasound shear wave elastography for the quantification of renal allograft stiffness. RESULTS: We evaluated 55 patients, of whom 9 (16.4%) had an RI defined as abnormal (≥ 0.79) and 46 (83.6%) had an RI defined as normal (< 0.79). The mean age was higher in the abnormal RI group than in the normal RI group (68.0 ± 8.6 years vs. 42.6 ± 14.1 years; p < 0.001), as was the mean shear wave velocity (2.6 ± 0.4 m/s vs. 2.2 ± 0.4 m/s; p = 0.013). Multivariate analysis identified two independent predictors of arterial resistance: age (OR = 1.169; 95% CI: 1.056 to 1.294; p = 0.003) and shear wave velocity (OR = 17.1; 95% CI: 1.137 to 257.83; p = 0.040). CONCLUSION: We observed an association between rigidity in the cortex of the transplanted kidney, as evaluated by shear wave elastography, and arterial resistance, as evaluated by color Doppler, in kidney transplant recipients.
OBJETIVO: Avaliar a associação entre parâmetros de elastografia por onda de cisalhamento e resistência arterial em pacientes transplantados renais. MATERIAIS E MÉTODOS: Estudo transversal prospectivo. O estudo incluiu de forma consecutiva indivíduos adultos transplantados renais. Foram coletados dados demográficos e clínicos. Todos os pacientes foram submetidos à técnica ultrassonográfica para avaliação do índice de resistência (IR) e à quantificação da elasticidade do tecido por ondas de cisalhamento para avaliar a rigidez do aloenxerto renal. RESULTADOS: Foram avaliados 55 pacientes. A média de idade e a velocidade da onda de cisalhamento foram maiores em pacientes com IR ≥ 0,79 (respectivamente, 68,0 ± 8,6 anos e 2,6 ± 0,4 m/s) quando comparados a pacientes com IR < 0,79 (respectivamente, 42,6 ± 14,1 anos, p < 0,001 e 2,2 ± 0,4 m/s, p = 0,013). A análise multivariada identificou a idade (OR = 1,169, IC 95%: 1,056 a 1,294; p = 0,003) e a velocidade da onda de cisalhamento (OR = 17,1, IC 95%: 1,137 a 257,83; p = 0,040) como fatores independentes associados a resistência arterial. CONCLUSÃO: Observou-se associação entre a rigidez do córtex do transplante renal avaliada por elastografia por onda de cisalhamento e a resistência arterial em pacientes pós-transplantados renais avaliados por Doppler.
ABSTRACT
OBJECTIVE: To quantify iron deposits in the basal ganglia and to evaluate its relation to age, sex, body mass index and brain laterality. METHODS: Prospective observational study. Data were collected from the patients' electronic medical records. The concentration of iron deposits in the brain was assessed using whole-brain MRI at 3.0 Tesla. RESULTS: 138 participants were selected, 69.6% were female and the mean age was 47 ± 19 years. The κ coefficient was very strong (k = 0.92, p < 0.001). Age showed a moderate correlation between iron deposits in the caudate and putamen nuclei, on both right and left sides. In overall and right-handed individuals, a significantly higher iron concentration was observed on the left side for the caudate nucleus, putamen, thalamus, globus pallidus, and centrum semiovale, and for left-handed individuals, it was also observed in the left side-for the putamen and centrum semiovale. A weak correlation was shown between body mass index and left and right substantia nigra, left caudate nuclei, left putamen and right globus pallidus. CONCLUSION: Our results showed a significantly higher iron deposit on the left side in most brain regions. In addition, the body mass index may also be related to iron overload, especially in the caudate nucleus. ADVANCES IN KNOWLEDGE: Brain iron deposits may be normal, owing to aging, or be pathological, such as neurodegeneration. Thus, it is important to know how much is expected of iron deposition in the brain of healthy populations.
Subject(s)
Iron , Magnetic Resonance Imaging , Adult , Aged , Brain/diagnostic imaging , Brain/pathology , Cross-Sectional Studies , Female , Humans , Magnetic Resonance Spectroscopy , Male , Middle Aged , Prospective StudiesABSTRACT
Abstract Objective: To evaluate the association between shear wave elastography parameters and arterial resistance in kidney transplant recipients. Materials and Methods: This was a prospective cross-sectional study involving consecutive adult kidney transplant recipients. All patients underwent color Doppler to evaluate the resistive index (RI) and ultrasound shear wave elastography for the quantification of renal allograft stiffness. Results: We evaluated 55 patients, of whom 9 (16.4%) had an RI defined as abnormal (≥ 0.79) and 46 (83.6%) had an RI defined as normal (< 0.79). The mean age was higher in the abnormal RI group than in the normal RI group (68.0 ± 8.6 years vs. 42.6 ± 14.1 years; p < 0.001), as was the mean shear wave velocity (2.6 ± 0.4 m/s vs. 2.2 ± 0.4 m/s; p = 0.013). Multivariate analysis identified two independent predictors of arterial resistance: age (OR = 1.169; 95% CI: 1.056 to 1.294; p = 0.003) and shear wave velocity (OR = 17.1; 95% CI: 1.137 to 257.83; p = 0.040). Conclusion: We observed an association between rigidity in the cortex of the transplanted kidney, as evaluated by shear wave elastography, and arterial resistance, as evaluated by color Doppler, in kidney transplant recipients.
RESUMO Objetivo: Avaliar a associação entre parâmetros de elastografia por onda de cisalhamento e resistência arterial em pacientes transplantados renais. Materiais e Métodos: Estudo transversal prospectivo. O estudo incluiu de forma consecutiva indivíduos adultos transplantados renais. Foram coletados dados demográficos e clínicos. Todos os pacientes foram submetidos à técnica ultrassonográfica para avaliação do índice de resistência (IR) e à quantificação da elasticidade do tecido por ondas de cisalhamento para avaliar a rigidez do aloenxerto renal. Resultados: Foram avaliados 55 pacientes. A média de idade e a velocidade da onda de cisalhamento foram maiores em pacientes com IR ≥ 0,79 (respectivamente, 68,0 ± 8,6 anos e 2,6 ± 0,4 m/s) quando comparados a pacientes com IR < 0,79 (respectivamente, 42,6 ± 14,1 anos, p < 0,001 e 2,2 ± 0,4 m/s, p = 0,013). A análise multivariada identificou a idade (OR = 1,169, IC 95%: 1,056 a 1,294; p = 0,003) e a velocidade da onda de cisalhamento (OR = 17,1, IC 95%: 1,137 a 257,83; p = 0,040) como fatores independentes associados a resistência arterial. Conclusão: Observou-se associação entre a rigidez do córtex do transplante renal avaliada por elastografia por onda de cisalhamento e a resistência arterial em pacientes pós-transplantados renais avaliados por Doppler.
