Usefulness of dynamic contrast-enhanced magnetic resonance imaging in characterizing ovarian tumors classified as indeterminate at ultrasonography.

OBJECTIVES: To determine whether there is a significant relationship between the shape of the time-intensity curve on dynamic gadolinium-enhanced magnetic resonance imaging (MRI) of ovarian tumours classified as indeterminate at ultrasonography and the type of lesion (benign, borderline, or malignant) to enable an accurate presurgical diagnosis. MATERIAL AND METHODS: We used dynamic contrast-enhanced MRI to study 68 ovarian tumours that were classified as indeterminate at ultrasonography. We included only cases for which a definitive diagnosis (histologic diagnosis or ≥1 year stability on imaging tests) was available. Each case was classified as benign, borderline, or malignant. To analyse the MRI studies, we marked regions of interest in the lesion and in the myometrium (as a reference). We obtained a curve defined by the relation between the intensity of enhancement and time and classified each tumour according to four predefined curve types. We also analysed semiquantitative parameters. Finally, we compared the results for each of the three groups of tumours. RESULTS: We found significant associations (P<.001) between the curves without early enhancement and benign and borderline lesions as well as between the curves with early enhancement and malignant lesions. Malignant lesions were significantly associated with the semiquantitative enhancement parameters: maximum (P=.002), maximum relative (P=.006), and relative (P=.018). CONCLUSIONS: In ovarian tumours classified as indeterminate at ultrasonography, dynamic contrast-enhanced MRI can be useful for classification as benign, borderline, or malignant because the malignant lesions are significantly associated with early enhancement curves.

Utilidad de la resonancia magnética dinámica con contraste para caracterizar tumores ováricos ecográficamente indeterminados / Usefulness of dynamic contrast-enhanced magnetic resonance imaging in characterizing ovarian tumors classified as indeterminate at ultrasonography

Objetivos: Determinar si existe una relación significativa entre la morfología de la curva intensidad-tiempo del estudio de resonancia magnética (RM) dinámica con gadolinio de los tumores ováricos ecográficamente indeterminados y el tipo de lesión (benigna, borderline o maligna), para poder realizar un diagnóstico prequirúrgico correcto. Material y métodos: Se analizaron 68 tumoraciones ováricas ecográficamente indeterminadas, valoradas mediante RM con secuencia dinámica. Únicamente se incluyeron los casos con diagnóstico histológico o con estabilidad en pruebas de imagen tras al menos un año de seguimiento. Cada caso se clasificó en benigno, borderline o maligno.Para su análisis, se marcaron regiones de interés en la lesión y en el miometrio (como referencia). Se obtuvo una curva definida por la relación entre la intensidad del realce y el tiempo, cuya morfología permitió clasificar cada tumor dentro de uno de los cuatro tipos de curva predefinidos. También se analizaron parámetros semicuantitativos. Finalmente, se compararon los resultados de cada uno de los tres grupos de tumores. Resultados: Se demostró una relación significativa (p <0,001) entre las curvas sin realce precoz con las lesiones benignas y borderline, y entre las malignas con curvas con realce precoz. Las lesiones malignas se asociaron de forma significativa con los parámetros semicuantitativos de realce: máximo (p=0,002), relativo máximo (p=0,006) y relativo (p=0,018). Conclusiones: En tumores ováricos ecográficamente indeterminados, la RM dinámica con contraste puede ser útil a la hora de clasificarlos como benignos, borderline o malignos, al mostrar las neoplasias malignas una asociación estadísticamente significativa con curvas con realce precoz.(AU)

Objectives:To determine whether there is a significant relationship between the shape of the time-intensity curve on dynamic gadolinium-enhanced magnetic resonance imaging (MRI) of ovarian tumors classified as indeterminate at ultrasonography and the type of lesion (benign, borderline, or malignant) to enable an accurate presurgical diagnosis. Material and methods: We used dynamic contrast-enhanced MRI to study 68 ovarian tumors that were classified as indeterminate at ultrasonography. We included only cases for which a definitive diagnosis (histologic diagnosis or ≥1 year stability on imaging tests) was available. Each case was classified as benign, borderline, or malignant. To analyze the MRI studies, we marked regions of interest in the lesion and in the myometrium (as a reference). We obtained a curve defined by the relation between the intensity of enhancement and time and classified each tumor according to four predefined curve types. We also analyzed semiquantitative parameters. Finally, we compared the results for each of the three groups of tumors. Results: We found significant associations (p <0.001) between the curves without early enhancement and benign and borderline lesions as well as between the curves with early enhancement and malignant lesions. Malignant lesions were significantly associated with the semiquantitative enhancement parameters: maximum (p=0.002), maximum relative (p=0.006), and relative (p=0.018). Conclusions: In ovarian tumors classified as indeterminate at ultrasonography, dynamic contrast-enhanced MRI can be useful for classification as benign, borderline, or malignant because the malignant lesions are significantly associated with early enhancement curves.(AU)

Incidence of contrast-induced nephropathy after a computed tomography scan.

BACKGROUND AND AIMS: The term contrast-induced nephropathy is used to describe acute deterioration of renal function after the intravenous administration of iodinated contrast material. We aimed to estimate the incidence of contrast-induced nephropathy and to analyze the evolution of different biomarkers of renal function in patients who underwent computed tomography with intravenous contrast administration after premedication with oral hydration and N-acetylcysteine. MATERIAL AND METHODS: This prospective observational study included 112 patients with chronic renal failure (glomerular filtration rate (GFR) 30ml-60ml/min/1.73m2) scheduled for computed tomography with intravenous iodinated contrast material. We recorded demographic variables, dose of contrast material, diabetes mellitus, hypertension, and serum hemoglobin. We measured serum creatinine and GFR after premedication and after the CT examination. We summarized variables as means, standard deviations, and percentages. We used the Wilcoxon and Mann-Whitney tests to compare pre- and post-CT values and Pearson's r to analyze correlations. RESULTS: Incidence acute kidney injury: 0.9%; 95%CI: 0.36-1.4. Mean difference between pre- and post-CT creatinine: 0.04; 95%CI: 0.002-0.09, p<0.004. Mean difference between pre- and post-CT GFR: -3.06; 95%CI: -4.66 to -1.47), p<0.001. CONCLUSIONS: The incidence of contrast-induced nephropathy in patients with chronic renal failure and GFR 30ml-60ml/min/1.73m2 is low. The biomarkers of renal function analyzed improve in patients who receive premedication and the minimum dose of contrast material.

Usefulness of dynamic contrast-enhanced magnetic resonance imaging in characterizing ovarian tumors classified as indeterminate at ultrasonography. / Utilidad de la resonancia magnética dinámica con contraste para caracterizar tumores ováricos ecográficamente indeterminados.

OBJECTIVES: To determine whether there is a significant relationship between the shape of the time-intensity curve on dynamic gadolinium-enhanced magnetic resonance imaging (MRI) of ovarian tumors classified as indeterminate at ultrasonography and the type of lesion (benign, borderline, or malignant) to enable an accurate presurgical diagnosis. MATERIAL AND METHODS: We used dynamic contrast-enhanced MRI to study 68 ovarian tumors that were classified as indeterminate at ultrasonography. We included only cases for which a definitive diagnosis (histologic diagnosis or ≥1 year stability on imaging tests) was available. Each case was classified as benign, borderline, or malignant. To analyze the MRI studies, we marked regions of interest in the lesion and in the myometrium (as a reference). We obtained a curve defined by the relation between the intensity of enhancement and time and classified each tumor according to four predefined curve types. We also analyzed semiquantitative parameters. Finally, we compared the results for each of the three groups of tumors. RESULTS: We found significant associations (p <0.001) between the curves without early enhancement and benign and borderline lesions as well as between the curves with early enhancement and malignant lesions. Malignant lesions were significantly associated with the semiquantitative enhancement parameters: maximum (p=0.002), maximum relative (p=0.006), and relative (p=0.018). CONCLUSIONS: In ovarian tumors classified as indeterminate at ultrasonography, dynamic contrast-enhanced MRI can be useful for classification as benign, borderline, or malignant because the malignant lesions are significantly associated with early enhancement curves.