RESUMEN
OBJECTIVES: A panel of 14 physicians practicing medicine in the United States with expertise in radiology, obstetrics and gynecology, gynecologic oncology, hysteroscopy, epidemiology, and pathology was convened by the Society of Radiologists in Ultrasound to discuss the role of sonography in women with postmenopausal bleeding. Broad objectives of this conference were (1) to advance understanding of the utility of different diagnostic techniques for evaluating the endometrium in women with postmenopausal bleeding; (2) to formulate useful and practical guidelines for evaluation of women with postmenopausal bleeding, specifically as it relates to the use of sonography; and (3) to offer suggestions for future research projects. SETTING: October 24 and 25, 2000, Washington, DC, preceding the annual Society of Radiologists in Ultrasound Advances in Sonography conference. PROCEDURE: Specific questions to the panel included the following: (1) What are the relative effectiveness and cost-effectiveness of using transvaginal sonography versus office (nondirected) endometrial biopsy as the initial examination for a woman with postmenopausal bleeding? (2) What are the sonographic standards for evaluating a woman with postmenopausal bleeding? (3) What are the abnormal sonographic findings in a woman with postmenopausal bleeding? (4) When should saline infusion sonohysterography or hysteroscopy be used in the evaluation of postmenopausal bleeding? (5) Should the diagnostic approach be modified for patients taking hormone replacement medications, tamoxifen, or other selective estrogen receptor modulators? CONCLUSIONS: Consensus recommendations were used to create an algorithm for evaluating women with postmenopausal bleeding. All panelists agreed that because postmenopausal bleeding is the most common presenting symptom of endometrial cancer, when postmenopausal bleeding occurs, clinical evaluation is indicated. The panelists also agreed that either transvaginal sonography or endometrial biopsy could be used safely and effectively as the first diagnostic step. Whether sonography or endometrial biopsy is used initially depends on the physician's assessment of patient risk, the nature of the physician's practice, the availability of high-quality sonography, and patient preference. Similar sensitivities for detecting endometrial carcinoma are reported for transvaginal sonography when an endometrial thickness of greater than 5 mm is considered abnormal and for endometrial biopsy when "sufficient" tissue is obtained. Currently, with respect to mortality, morbidity, and quality-of-life end points, there are insufficient data to comment as to which approach is more effective. The conference concluded by identifying several important unanswered questions and suggestions that could be addressed by future research projects.
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Neoplasias Endometriales/diagnóstico por imagen , Endometrio/diagnóstico por imagen , Posmenopausia/fisiología , Hemorragia Uterina/etiología , Algoritmos , Biopsia , Neoplasias Endometriales/complicaciones , Endometrio/patología , Endometrio/fisiología , Terapia de Reemplazo de Estrógeno , Femenino , Humanos , Histeroscopía , Radiología , Sociedades Médicas , UltrasonografíaRESUMEN
The objective of this study was to assess the value of combining transvaginal sonohysterography with three-dimensional multiplanar ultrasonography to optimize assessment of the uterus. To make this assessment, we compared findings on three-dimensional sonohysterography with those on two-dimensional sonohysterography and X-ray hysterosalpingography. Of 20 women who underwent three-dimensional sonohysterography for various indications, 13 also underwent two-dimensional sonohysterography, and 12 had X-ray hysterosalpingography. We reviewed the 3 types of examinations separately and compared the standard techniques with three-dimensional sonohysterography to determine whether three-dimensional sonohysterography provided additional information. In 9 (69%) of 13 comparisons between three-dimensional sonohysterography and two-dimensional sonohysterography and in 11 (92%) of 12 comparisons between three-dimensional sonohysterography and X-ray hysterosalpingography, three-dimensional sonohysterography was advantageous. The coronal plane was most useful for displaying the relationship between lesions and the uterine cavity. Three-dimensional sonohysterography provided additional information compared with standard accepted techniques in the vast majority of women.
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Histerosalpingografía , Imagenología Tridimensional , Útero/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Adherencias Tisulares , Ultrasonografía/métodos , Enfermedades Uterinas/diagnóstico por imagen , Neoplasias Uterinas/diagnóstico por imagenRESUMEN
PURPOSE: To analyze ultrasonographic (US), computed tomographic (CT), and magnetic resonance (MR) imaging features of primary and secondary ovarian malignant neoplasms to determine if there is any significant difference in their appearance. MATERIALS AND METHODS: Analysis of the multi-institutional Radiology Diagnostic Oncology Group data revealed 86 patients with primary ovarian carcinoma and 24 patients with a secondary ovarian neoplasm. Numerous imaging features that had been recorded for the adnexal masses with each imaging modality were reviewed and compared between primary and secondary malignant ovarian neoplasms. RESULTS: Of the imaging features assessed with all three modalities, multilocularity as determined at US (P =.02) or MR imaging (P: =.01) was the only significant feature. At US, 30 (37%) of 81 primary ovarian cancers were multilocular, whereas only three (12%) of 24 metastatic neoplasms were multilocular. At MR imaging, 40 (74%) of 54 primary ovarian cancers were multilocular, whereas only five (36%) of 14 metastatic neoplasms were multilocular. Neither a predominately solid appearance nor bilaterality was significantly different between primary and secondary neoplasms. CONCLUSION: For malignant ovarian masses, multilocularity at MR imaging or US favors the diagnosis of primary ovarian malignancy rather than secondary neoplasm, but it is difficult to accurately distinguish between primary and secondary ovarian malignancies.
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Diagnóstico por Imagen , Neoplasias Primarias Secundarias/diagnóstico , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/secundario , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Neoplasias Primarias Secundarias/patología , Neoplasias Ováricas/patología , Ovario/patología , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
PURPOSE: To compare ultrasonography (US), magnetic resonance (MR) imaging, and computed tomography (CT) for diagnosing and staging advanced ovarian cancer. MATERIALS AND METHODS: US, CT, and MR imaging were performed in 280 patients. Images were read by three radiologists from each of the five hospitals. Image analysis included determination of malignancy within the peritoneum (11 sites), lymph nodes (10 sites), and hepatic parenchyma. The standard of reference was based on surgical and histopathologic findings. Statistical methods used were receiver operating characteristic (ROC) curve analysis, pairwise comparison of areas under the ROC curves (A(z)), analysis of sensitivity and specificity pairs, and assessment of agreement between the degree of suspicion and standard of reference. RESULTS: There were 118 patients with malignant tumors; 73 (62%) had stage III or IV disease. Metastases were found in the peritoneum in 70 (59%), nodes in 20 (17%), and liver in seven (6%) cases. In the peritoneum, MR imaging and CT (A(z) = 0.96 for both) were more accurate than US (A(z) = 0.86), especially in the subdiaphragmatic spaces and hepatic surfaces. MR imaging and CT were more sensitive than US (95%, 92%, and 69%, respectively) for peritoneal metastases. MR imaging was more accurate than CT for detection of lymph node metastases (A(z) = 0.76 vs 0.57, P =.04). In the liver, the A(z) values for the three modalities were 0.77-0.94. CONCLUSION: CT and MR imaging are equally accurate, and either modality can be used to stage advanced ovarian cancer.
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Neoplasias Ováricas/patología , Adulto , Anciano , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Metástasis Linfática , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/estadística & datos numéricos , Persona de Mediana Edad , Estadificación de Neoplasias , Variaciones Dependientes del Observador , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/cirugía , Ovario/diagnóstico por imagen , Ovario/patología , Estudios Prospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Ultrasonografía Doppler/métodos , Ultrasonografía Doppler/estadística & datos numéricos , Estados UnidosRESUMEN
OBJECTIVE: To evaluate the feasibility and accuracy of fetal gender assignment from three-dimensional ultrasound (3D US) data at 10-24 weeks' gestation. METHODS: Three-dimensional ultrasound volume data on 47 fetuses were reviewed and divided into groups: 10-14, 15-18, and 19-24 weeks. Fetal genitalia were studied in axial and sagittal planes for gender assignment, using published criteria. The most valuable plane for assignment was noted. Gender assignment was compared with gender at birth. RESULTS: Gender assignment was possible in 44 of 47 fetuses; 25 assigned male and 19 female. Between 10 and 14 weeks the mid-sagittal plane alone was diagnostic for all fetuses. Accuracy of assignment between 11 and 14 weeks was 100%. Between 15 and 18 and 19 to 24 weeks, male assignment was 100% accurate. Female assignment was 100% accurate between 15 and 18 weeks. Accuracy decreased to 60% in the 19 to 24 week group, however, in two of the five cases in which gender was wrongly assigned to be male, the assignment was prospectively considered doubtful due to poor resolution of volume data. Excluding these two cases, accuracy for female assignment in the 19-24 week group was 100%. CONCLUSION: Using 3D US, gender assignment was possible in 44 of 47 of fetuses, as early as 11 weeks' gestation. In early gestation, 11-14 weeks, accuracy of male and female gender assignment was 100%.
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Genitales Femeninos/anatomía & histología , Genitales Masculinos/anatomía & histología , Análisis para Determinación del Sexo/métodos , Ultrasonografía Prenatal/métodos , Estudios de Factibilidad , Femenino , Edad Gestacional , Humanos , MasculinoRESUMEN
PURPOSE: To determine the optimal imaging modality for diagnosis and staging of ovarian cancer. MATERIALS AND METHODS: Two hundred eighty women suspected to have ovarian cancer were enrolled in a prospective study before surgery. Doppler ultrasonography (US), computed tomography (CT), and magnetic resonance (MR) imaging were used to evaluate the mass; conventional US, CT, and MR imaging were used to stage spread. RESULTS: All three modalities had high accuracy (0.91) for the overall diagnosis of malignancy. In the ovaries, the accuracy of MR imaging (0.91) was higher than that of CT and significantly higher than that of Doppler US (0.78). In the extraovarian pelvis and in the abdomen, conventional US, CT, and MR imaging had similar accuracies (0.87-0.95). In differentiation of disease confined to the pelvis from abdominal spread, the specificity of conventional US (96%) was higher than that of CT and significantly higher than that of MR imaging (88%), whereas the sensitivities of MR imaging (98%) and CT (92%) were significantly higher than that of conventional US (75%). CONCLUSION: MR imaging is superior to Doppler US and CT in diagnosis of malignant ovarian masses. There is little variation among conventional US, CT, and MR imaging as regards staging.
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Diagnóstico por Imagen , Neoplasias Ováricas/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Ováricas/patología , Neoplasias Ováricas/cirugía , Ovario/patología , Estudios Prospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , Ultrasonografía , Ultrasonografía DopplerRESUMEN
Color Doppler sonographic detection of tumor flow within superficial melanoma metastases was investigated to determine if tumor size, vessel size, or vessel number influences signal detection. Color Doppler imaging of 32 pathologically proved melanoma metastases was performed at 6 MHz with color Doppler imaging parameters optimized for each lesion scanned. All lesions were measured in three dimensions and the presence or absence of internal flow was documented. Seven surgically excised metastases underwent immunohistochemical staining for endothelial markers. Internal flow was detected in 21 of 32 masses and was completely absent in 11. In comparison to all masses without flow, the masses with flow had significantly greater anteroposterior dimensions (P < 0.00036) and volumes (P < 0.01). Histologically, mean vessel diameter in masses with flow was significantly greater (P < 0.05) than in those without flow, but mean vessel number was not significantly different. In conclusion, detectability of tumor blood flow in superficial melanoma metastasis may be related more to tumor size and vessel size than vessel number. Failure to detect color signal within a superficial melanoma mass does not indicate a lack of internal vascularity.
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Melanoma/irrigación sanguínea , Neoplasias Cutáneas/irrigación sanguínea , Ultrasonografía Doppler en Color , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD34 , Vasos Sanguíneos/diagnóstico por imagen , Vasos Sanguíneos/patología , Colorantes , Endotelio Vascular/patología , Humanos , Inmunohistoquímica , Melanoma/diagnóstico por imagen , Melanoma/patología , Melanoma/secundario , Persona de Mediana Edad , Flujo Sanguíneo Regional , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/secundarioRESUMEN
OBJECTIVE: The purpose of this study was to describe the sonographic appearances of melanoma metastases of the skin, subcutaneous tissues, and superficial lymph nodes. MATERIALS AND METHODS: Gray-scale sonography was performed on 31 superficial melanoma metastases in 18 patients. Discreteness of borders, contours, echogenicity, echotexture, and degree of acoustic through-transmission were evaluated for each lesion. Color Doppler sonography was also performed on 25 of the 31 lesions, by which the amount of internal color flow was qualitatively assessed. RESULTS: Twenty-eight (90%) of the 31 metastases had well-defined borders. Contours were smooth in 17 (55%), lobulated in 12 (39%), and spiculated in two (6%). Nineteen metastases (61%) were hypoechoic to muscle, 10 (32%) were isoechoic, and two (6%) were hyperechoic. Echotexture was homogeneous in six lesions (19%), mildly heterogeneous in 13 (42%), moderately heterogeneous in 11 (35%), and markedly heterogeneous in one (3%). Twenty-two lesions (71%) showed enhanced acoustic through-transmission. Of the 25 melanoma metastases for which we performed color Doppler sonography, 18 (72%) had internal arterial color flow and seven (28%) did not. The flow was characterized as mild in 13 (72%) of 18, moderate in four (22%), and marked in one (6%). CONCLUSION: On sonography, superficial melanoma metastases typically are well-defined hypoechoic lesions with smooth or lobulated contours, mild to moderate heterogeneity, and enhanced acoustic through-transmission. Internal flow revealed by color Doppler sonography is present in many, but not all, superficial melanoma metastases.
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Melanoma/diagnóstico por imagen , Melanoma/secundario , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/secundario , Ultrasonografía Doppler en Color , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias Cutáneas/patologíaRESUMEN
PURPOSE: To evaluate incidental pulmonary emboli detected at helical computed tomography (CT) and the effect on patient care. MATERIALS AND METHODS: A computer search of reports from 1,879 consecutive contrast material-enhanced helical CT scans identified 28 cases in which pulmonary emboli were suggested. These 28 scans were rereviewed by three radiologists to confirm intraluminal defects. Six cases were excluded (three because of tumor invasion, two arterial stump thrombi after pneumonectomy, one artifact). In four cases, pulmonary emboli were clinically suspected or diagnosed prior to CT. Pulmonary embolus was not suspected at CT in the remaining 18 patients who constituted the study group. The medical records were reviewed for predisposing factors, suspicion of pulmonary embolism, adjuvant studies, and resultant therapy. RESULTS: All 18 patients in the study group had predisposition for thromboembolic disease. Seven of these patients underwent confirmatory or correlative studies (angiography, radionuclide studies, or autopsy), and four patients had supportive studies documenting deep venous thrombosis. Eleven patients received anticoagulants or caval filter placement as a result of CT findings. CONCLUSION: Incidental pulmonary emboli were detected in approximately 1% of patients who underwent contrast-enhanced CT of the chest. All of these patients were at high risk for emboli. Therapeutic intervention was undertaken in 61% of these patients. While ultimate patient outcome is uncertain, the incidental CT diagnosis of pulmonary emboli appears accurate and affects patient care.
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Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/uso terapéutico , Causalidad , Medios de Contraste , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Prevalencia , Embolia Pulmonar/epidemiología , Embolia Pulmonar/terapia , Factores de Riesgo , Filtros de Vena CavaRESUMEN
PURPOSE: To determine the effects of level of training and other factors on the rate of discrepant interpretation of emergency body computed tomographic (CT) scans by trainees and staff radiologists. MATERIALS AND METHODS: Five hundred ninety-eight consecutive emergency CT studies were prospectively interpreted by radiology residents or board-certified body imaging fellows over a 12-month period. Each interpretation was reviewed within 12 hours by an attending body CT radiologist. Major discrepancies between staff radiologists' and trainees' interpretations were defined and those with the potential to affect immediate patient therapy; minor discrepancies were defined ad those without such potential. The effects on discrepancy rates were examined for abnormal versus normal CT findings and trauma versus nontrauma cases. RESULTS: Major and minor discrepancy rates were 1.2% and 6.5%, respectively, between interpretations made by the trainee and the staff radiologist. Overall, fellows demonstrated statistically significantly lower discrepancy rates than did senior of junior residents (5.9%, 13.7%, and 13.3%, respectively). The discrepancy rate was higher when CT findings were abnormal than when they were normal (13.5% vs 2.6%). There were no differences between discrepancy rates for trauma and nontrauma cases. CONCLUSION: Experience appeared to decrease discrepancy rates. Trainees were more likely to miss findings than to read normal scans as abnormal.
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Radiología/educación , Tomografía Computarizada por Rayos X , Certificación , Errores Diagnósticos , Urgencias Médicas , Humanos , Internado y Residencia , Estudios Prospectivos , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Heridas y Lesiones/diagnóstico por imagenRESUMEN
PURPOSE: To evaluate the impact of superficial ultrasonography (US) on clinical management of melanoma. MATERIALS AND METHODS: Superficial US in areas at high risk for local recurrence or nodal metastases was performed in 33 patients with cutaneous melanoma. Impact categories were assigned to each US study (n = 55): category 3, US added information that altered clinical management; category 2, US added information that did not change management; category 1, no added information and management unchanged; category 0, not helpful or was misleading. RESULTS: Twenty-two US studies (40%) were category 3: detection of nonpalpable metastases altered surgical therapy (n = 2), demonstration of pharmacodynamic response to chemotherapy (n = 5), and determination of benignancy or malignancy (n = 15). Nine (16%) were category 2: identification of nonpalpable metastases did not alter management. Twenty-two (40%) were category 1: supported clinical impression of no metastases (n = 18) or helped confirm cutaneous, subcutaneous, or nodal metastases (n = 4). Two (4%) were category 0: missed proved metastases. CONCLUSION: Superficial US affected management of melanoma by allowing detection and characterization of masses, guidance of biopsy, and assessment of pharmacodynamic response.
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Melanoma/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Melanoma/secundario , Melanoma/terapia , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias Cutáneas/terapia , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/secundario , Neoplasias de los Tejidos Blandos/terapia , Resultado del Tratamiento , UltrasonografíaRESUMEN
Analyzing fetal interval growth may improve detection of growth abnormalities. This study establishes normal limits for growth rates of fetal biparietal diameter, abdominal diameter, abdominal circumference, and femur length. Fetal measurements were obtained during 1450 obstetrical sonographic examinations in 510 patients with normal-weight term deliveries. Using a random-effects model for longitudinal data, cubic curves of size versus mean gestational age were fitted using a restricted maximum likelihood technique. Quadratic growth rate curves were then calculated as derivatives of the fitted curves. The growth rate equations are as follows: Biparietal diameter growth rate = 2.59 + 0.127 (MGA) - 0.000447 (MGA)2; abdominal diameter growth rate = 3.61 + 0.0325 (MGA) - 0.0017 (MGA)2; abdominal circumference growth rate = 11.3 + 0.102 (MGA) - 0.00534 (MGA)2; and femur length growth rate = 5.49 - 0.17 (MGA) + 0.00181 (MGA)2. Rates are expressed in mm/wk and mean gestational age in wk. Because standard deviations depend on the time interval between examinations, separate growth rate tables are provided for intervals of 4, 6, 8, and > or = 10 weeks.
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Desarrollo Embrionario y Fetal , Ultrasonografía Prenatal , Largo Cráneo-Cadera , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Edad Gestacional , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Embarazo , Valores de ReferenciaRESUMEN
OBJECTIVE: Evaluation of the cerebral ventricular system is a routine part of all fetal sonographic examinations. Ventriculomegaly and decreased choroid volume are indicators of poor fetal outcome, so it is important to know the normal variation of these parameters. The present study describes the normal size of the fetal lateral ventricular atrium and the normal amount of choroid plexus within the atrium during the second and third trimesters. SUBJECTS AND METHODS: Six hundred eight consecutive, healthy, singleton fetuses from 13 to 42 weeks' menstrual age were examined prospectively. The atrium of the lateral ventricle was measured in the axial and coronal planes. For each axial measurement, the width of the choroid plexus was determined. RESULTS: An axial atrial measurement was obtained in 88% of the fetuses, and a coronal atrial measurement was obtained in 84%. The mean measurement and one standard deviation are 6.5 +/- 1.5 mm in the axial plane and 6.6 +/- 1.5 mm in the coronal plane. Ninety-eight percent of all measured atria were at least 60% filled by choroid plexus, and in all cases the atria were at least 50% filled. Complete filling by choroid plexus occurred in 58% of cases. CONCLUSION: This large prospective study confirms previous observations of mean atrial size. However, four standard deviations above the mean is 12 mm, suggesting currently used cutoffs for normal atrial size are too low. Other parameters, such as choroid plexus filling, may be helpful markers of normalcy in fetuses with atrial measurements between 8 and 12 mm.
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Ventrículos Cerebrales/diagnóstico por imagen , Plexo Coroideo/diagnóstico por imagen , Ultrasonografía Prenatal , Ventrículos Cerebrales/embriología , Plexo Coroideo/embriología , Femenino , Edad Gestacional , Humanos , Embarazo , Estudios Prospectivos , Valores de ReferenciaRESUMEN
This case describes the first report of a patient developing Cushing's syndrome whilst being treated with the synthetic progestogen, megestrol acetate (Megace). Drugs are the commonest cause of Cushing's syndrome. Some synthetic progestogens are known to have glucocorticoid activity at high doses. On structural grounds neither megestrol nor its major metabolites would be expected to interact with the glucocorticoid receptor, through the manufacturers report that it may have 'weak glucocorticoid activity'.
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Síndrome de Cushing/inducido químicamente , Megestrol/efectos adversos , Adenocarcinoma/tratamiento farmacológico , Adulto , Diabetes Mellitus Tipo 1/complicaciones , Femenino , Humanos , Neoplasias Uterinas/tratamiento farmacológicoRESUMEN
OBJECTIVE: Fetal growth rates determined on the basis of findings at two separate sonographic examinations can be used to detect growth abnormalities. This article determines the relationship between the length of the interval between examinations and the associated variability in measured fetal growth rates. MATERIALS AND METHODS: We analyzed 1479 fetal measurements of the biparietal diameter, average abdominal diameter, and femur length from 539 normal pregnancies. Mean growth rates were computed as functions of gestational age. The standard deviation of the growth rate was computed as a function of the interval between examinations. RESULTS: The standard deviation of fetal growth rates is relatively constant when the interval between examinations is 8-10 weeks or more, but increases substantially when the interval is fewer than 6 weeks. CONCLUSION: From a purely statistical point of view, the optimal interval for assessment of fetal growth rates is 8-10 weeks or more. Shorter intervals, however, usually are mandated by the clinical situation. Correction factors can be used to determine the standard deviations and associated confidence intervals for fetal growth measured over a period of fewer than 10 weeks.
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Desarrollo Embrionario y Fetal , Ultrasonografía Prenatal , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Edad Gestacional , Humanos , Embarazo , Factores de TiempoRESUMEN
We evaluated normal uterine involution prospectively with real-time ultrasonography in 100 women after uncomplicated term vaginal delivery. Transducers easily distorted the spongy uterus during early postpartum scanning, an effect minimized with sector transducers that are superior to linear or convex probes for accurate early postpartum uterine measurement. Long-axis measurements correcting for uterine angulation were the most reproducible and accurate, irrespective of bladder distention. Uterine contractions caused instability of particularly the transverse dimension. Increasing maternal parity was associated with slightly but significantly larger uterine dimensions up to 4 weeks post partum. The uterus reassumed nongravid dimensions by 6 to 8 postpartum weeks. Uterine involution was unrelated to infant birth weight or breast feeding.