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1.
Eur Radiol ; 29(3): 1435-1443, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30120494

RESUMO

OBJECTIVES: To prospectively determine the feasibility of preoperative supine breast MRI in breast cancer patients scheduled for oncoplastic breast-conserving surgery. METHODS: In addition to a diagnostic prone breast MRI, a supplementary supine MRI was performed with the patient in the surgical position including skin markers. Tumours' locations were ink-marked on the skin according to findings obtained from supine MRI. Changes in tumours' largest diameter and locations between prone and supine MRI were measured and compared to histology. Nipple-to-tumour and tumour-to-chest wall distances were also measured. Tumours and suspicious areas were surgically removed according to skin ink-markings. The differences between MRI measurements with reference to histopathology were evaluated with the paired-sample t test. RESULTS: Fourteen consecutive patients, 15 breasts and 27 lesions were analysed. Compared to histology, prone MRI overestimated tumour size by 47.1% (p = 0.01) and supine MRI by 14.5% (p = 0.259). In supine MRI, lesions' mean diameters and areas were smaller compared to prone MRI (- 20.9%, p = 0.009 and - 38.3%, p = 0.016, respectively). This difference in diameter was more pronounced in non-mass lesions (- 31.2%, p = 0.031) compared to mass lesions (- 9.2%, p = 0.009). Tumours' mean distance from chest wall diminished by 69.4% (p < 0.001) and from nipple by 18.2% (p < 0.001). Free microscopic margins were achieved in first operation in all patients. CONCLUSIONS: Supine MRI in the surgical position is feasible and useful in the precise localisation of prone MRI-detected lesions and provides a helpful tool to implement in surgery. Supine MRI more accurately determines tumours' size and location and might have an important role to diminish overestimations. KEY POINTS: • Breath-hold supine breast MRI is feasible using commercially available coils and sequences. • Size and area of lesions on MRI were consistently smaller when measured from the supine position as compared to the prone position. • Supine breast MRI is useful in the precise preoperative localisation of prone MRI-detected lesions. •.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Mastectomia Segmentar/métodos , Decúbito Dorsal , Adulto , Idoso , Neoplasias da Mama/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
2.
Physiol Meas ; 35(4): 533-47, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24577344

RESUMO

Quantification of regional myocardial blood flow (rMBF) with first-pass magnetic resonance imaging (FP-MRI) requires two contrast agent injections (dual bolus technique), inducing error in the determined rMBF if the injections differ. We hypothesize that using input and residue curves of the same injection would be more reliable. We aim to introduce and evaluate a novel method to correct the high concentration arterial input function (AIF) for determination of rMBF. Sixteen patients with non-Hodgkin's lymphoma were examined before and after chemotherapy. The input function was solved by correcting initial high concentration AIF using the ratio of low and high contrast AIF areas, normalized by corresponding heart rates (modified dual bolus method). For comparison, the scaled low contrast AIF was used as an input function (dual bolus method). Unidirectional transfer coefficient K(trans) was calculated using both methods. K(trans)-values determined with the dual bolus (0.81 ± 0.32 ml g(-1) min(-1)) and modified dual bolus (0.77 ± 0.42 ml g(-1) min(-1)) methods were in agreement (p = 0.21). Mean K(trans)-values increased from 0.76 ± 0.43 to 0.89 ± 0.55 ml g(-1) min(-1) after chemotherapy (p = 0.17). The modified dual bolus technique agrees with the dual bolus technique (R2 = 0.899) when the low and high contrast injections are similar. However, when this is not the case, the modified dual bolus technique may be more reliable.


Assuntos
Imageamento por Ressonância Magnética/métodos , Imagem de Perfusão do Miocárdio/métodos , Artérias/fisiologia , Relação Dose-Resposta a Droga , Tratamento Farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador , Fatores de Tempo
3.
J Hum Hypertens ; 25(12): 746-51, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21248782

RESUMO

Early detection of left ventricular hypertrophy (LVH) is beneficial, since treatment-induced regression of LVH has been unequivocally associated with a better prognosis. Our aim was to study the relation of cardiac remodelling and natriuretic peptides (NPs) in stage 1 hypertension. We studied 175 (46±7 years, 87 women and 88 men) apparently healthy middle-aged that had never been treated for hypertension. Left ventricular and atrial parameters were determined by magnetic resonance imaging. Systolic blood pressure (BP) correlated with left ventricular mass index (LVMI) (r=0.23, P<0.01) and ventricular septum thickness index (IVSI) (r=0.29, P<0.001). N-terminal pro-B-type NP (NT-proBNP) or N-terminal pro-atrial NP (NT-proANP) did not correlate with BP, LVMI or IVSI. NT-proANP correlated with left atrial area index (LAAI) (r=0.38, P<0.001), and subjects with LVH had higher LAAI than subjects with normal left ventricular geometry and no LVH (11.2±0.3 vs 10.0±0.2 cm(2) m(-2), P<0.001). In conclusion, measurement of NT-proBNP or NT-proANP does not appear to discriminate LVH in middle-aged, never treated and apparently healthy hypertensives. NT-proANP, but not NT-proBNP, reflects early cardiac remodelling in hypertensive heart disease.


Assuntos
Fator Natriurético Atrial/sangue , Hipertensão/complicações , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/patologia , Fragmentos de Peptídeos/sangue , Remodelação Ventricular/fisiologia , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Hipertensão/sangue , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/sangue , Incidência , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Índice de Gravidade de Doença
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