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1.
Radiology ; 268(2): 356-65, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23657893

RESUMEN

PURPOSE: To develop and apply a semiautomatic method of segmenting fibroglandular tissue to quantify magnetic resonance (MR) imaging contrast material-enhancement kinetics of breast background parenchyma (BP) and lesions throughout the phases of the menstrual cycle in women with benign and malignant lesions. MATERIALS AND METHODS: The institutional review board approved this retrospective HIPAA-compliant study, and informed consent was waived. From December 2008 to August 2011, 58 premenopausal women who had undergone contrast material-enhanced MR imaging and MR imaging-guided biopsy were identified. The longest time from the start of the last known period was 34 days. One lesion per patient (37 benign and 21 malignant) was analyzed. The patient groups were stratified according to the week of the menstrual cycle when MR imaging was performed. A method based on principal component analysis (PCA) was applied for quantitative analysis of signal enhancement in the BP and lesions by using the percentage of slope and percentage of enhancement. Linear regression and the Mann-Whitney U test were used to assess the association between the kinetic parameters and the week of the menstrual cycle. RESULTS: In the women with benign lesions, percentages of slope and enhancement for both BP and lesions during week 2 were significantly (P < .05) lower than those in week 4. Percentage of enhancement in the lesion in week 2 was lower than that in week 3 (P < .05). The MR images of women with malignant lesions showed no significant difference between the weeks for any of the parameters. There was a strong positive correlation between lesion and BP percentage of slope (r = 0.72) and between lesion and BP percentage of enhancement (r = 0.67) in the benign group. There was also a significant (P = .03) difference in lesion percentage of slope between the benign and malignant groups at week 2. CONCLUSION: The PCA-based method can quantify contrast enhancement kinetics of BP semiautomatically, and kinetics of BP and lesions vary according to the week of the menstrual cycle in benign but not in malignant lesions.


Asunto(s)
Neoplasias de la Mama/patología , Mama/fisiología , Medios de Contraste/farmacocinética , Gadolinio DTPA/farmacocinética , Imagen por Resonancia Magnética/métodos , Ciclo Menstrual/fisiología , Adulto , Biopsia , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Modelos Lineales , Imagen por Resonancia Magnética Intervencional , Persona de Mediana Edad , Análisis de Componente Principal , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Estadísticas no Paramétricas
2.
J Magn Reson Imaging ; 38(4): 802-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23389833

RESUMEN

PURPOSE: To assess dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) tracer pharmacokinetic parameters obtained with Generalized Kinetic Model (GKM) and extended Shutter Speed Model (SSM2) in renal tumors stratified by histologic subtypes. MATERIALS AND METHODS: In all, 24 patients with renal tumors were imaged at 1.5 T utilizing DCE-MRI with high temporal resolution (1.2 sec/temporal frame) prior to surgery. Tracer kinetic analysis was performed for the entire tumor using individualized aortic input function. GKM and SSM2 were employed to generate transfer constant (K(trans)), plasma volume, and interstitial volume. These parameters, and ΔK(trans) (K(trans)SSM2 - K(trans)GKM) were compared between tumors stratified by histologic subtype. RESULTS: There were 25 renal tumors: 15 clear cell, 4 papillary, 3 chromophobe, and 3 oncocytoma/oncocytic subtype. K(trans)GKM was significantly higher in chromophobe compared to other subtypes (P < 0.01). Using K(trans)GKM > 1.0 min(-1), chromophobe were diagnosed with 100% sensitivity and 90.9% specificity. K(trans)SSM2 was higher than K(trans)GKM for all renal tumors except for all chromophobe and two clear cell subtype. Using K(trans)GKM > 1.0 min(-1) and Δ K(trans) < 0, chromophobe could be discriminated from other lesions with 100% accuracy. CONCLUSION: K(trans) obtained with GKM and SSM2 analysis can potentially discriminate chromophobe from other renal lesions with high accuracy.


Asunto(s)
Adenoma Oxifílico/patología , Carcinoma de Células Renales/patología , Medios de Contraste/farmacocinética , Gadolinio/farmacocinética , Neoplasias Renales/patología , Imagen por Resonancia Magnética , Adenoma Oxifílico/diagnóstico , Adulto , Anciano , Algoritmos , Carcinoma de Células Renales/diagnóstico , Estudios de Cohortes , Diagnóstico por Computador , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Neoplasias Renales/diagnóstico , Cinética , Masculino , Persona de Mediana Edad , Pronóstico
3.
Fertil Steril ; 95(3): 1178-81, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21047632

RESUMEN

In this case-control study of euthyroid first-cycle IVF patients ≥ 38 years old with singleton baby, miscarriage, biochemical pregnancy, and no pregnancy outcomes from 2005-2008, we assayed frozen serum for autoimmune thyroid disease (AITD) and thyroid function at cycle start, trigger, and 4 and 5 weeks' gestation. AITD prevalence in older infertile women was similar across clinical outcomes, and although AITD was associated with a higher baseline TSH, TSH remained within acceptable ranges, suggesting that T(4) supplementation may not affect maternal outcomes in older euthyroid AITD patients through 5 weeks gestation.


Asunto(s)
Fertilización In Vitro/estadística & datos numéricos , Infertilidad Femenina/epidemiología , Resultado del Embarazo/epidemiología , Glándula Tiroides/fisiología , Tiroiditis Autoinmune/epidemiología , Aborto Espontáneo/epidemiología , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Hipotiroidismo/epidemiología , Infertilidad Femenina/terapia , Edad Materna , Embarazo , Prevalencia
4.
Hum Reprod ; 25(9): 2298-304, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20659910

RESUMEN

BACKGROUND: To minimize the potential for harmful inheritable conditions, donors are rigorously screened according to standard guidelines, yet such guidelines may not be sufficient to exclude egg donors with certain known inheritable conditions. We compared universal screening of oocyte donors with Tay-Sachs, Fragile X, karyotype and Minnesota Multiphasic Personality Inventory-2 (MMPI-2) versus standard American Society of Reproductive Medicine (ASRM) guidelines that do not include such testing. METHODS: In this 12 year retrospective cohort study, results of enhanced universal screening of all anonymous oocyte donor candidates from 1997 to 2008 at a university hospital oocyte donation program were reviewed. Primary outcomes were the frequency of oocyte donor candidates excluded as a result of enhanced universal screening (Tay-Sachs, Fragile X, karyotypic analysis and MMPI-2) versus basic screening according to ASRM guidelines. RESULTS: Of 1303 candidates who underwent on-site evaluation, 47% passed the screening process, 23% were lost to follow-up and 31% were excluded. Genetic and psychological factors accounted for the most common reasons for candidate exclusion. Enhanced genetic screening excluded an additional 25 candidates (19% of all genetic exclusions) and enhanced psychological screening excluded an additional 15 candidates (12% of all psychological exclusions). Altogether enhanced screening accounted for 40 candidates (10%) of the total pool of excluded candidates. CONCLUSIONS: Although our study is limited by its retrospective nature and center-specific conclusions, we show that enhanced comprehensive screening can exclude a significant number of candidates from an oocyte donor program and should be encouraged to assure optimal short-term and long-term outcomes for pregnancies achieved through oocyte donation.


Asunto(s)
Selección de Donante/métodos , Pruebas Genéticas , Evaluación de Necesidades , Donación de Oocito , Pruebas Psicológicas , Adolescente , Adulto , Aberraciones Cromosómicas , Estudios de Cohortes , Selección de Donante/estadística & datos numéricos , Femenino , Síndrome del Cromosoma X Frágil/genética , Pruebas Genéticas/tendencias , Heterocigoto , Hospitales Universitarios/estadística & datos numéricos , Humanos , MMPI , Donación de Oocito/psicología , Guías de Práctica Clínica como Asunto , Control de Calidad , Estudios Retrospectivos , Enfermedad de Tay-Sachs/genética , Adulto Joven
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