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1.
Morphologie ; 107(356): 116-126, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35739008

RESUMO

OBJECTIVE: To describe and model the normal growth of fetal facial bones and angles. MATERIAL AND METHODS: A total of 118 fetal CT scans obtained at 19 to 41 weeks gestation after in utero fetal death or late miscarriage were analyzed. CT scan was followed by autopsy and pathological examination and only fetuses free from brain disease or abnormal craniofacial development were included. The measurements were taken using software for frontal, sagittal and 3D reconstruction from native axial sections. The optimal plane for bone analysis was chosen and the measurements made by multiplanar reconstruction. RESULTS: There was a statistically significant increase (P<0.001) in all measurements regardless of gestational age (GA) except those of the mandibulo-fronto-maxillary angle (P=0.412), the naso-mandibulo-maxillary angle (P=0.828) and mandibular width (P=0.86). There was no significant difference according to fetal sex. Based on these results, the corresponding growth curves were created. The anteroposterior mandibular diameter (APD) was very strongly correlated with GA (R=0.926, P<0.001). The following equation: GA=(8.187×APD)+4.257 can be used to estimate GA with a confidence interval (CI) of±2.42. The same applies to maxillary width (MW) (R=0.922; P<0.001). The equation GA=(11.059×MW)+7.571 can be used to estimate GA with a CI of 2.17. CONCLUSION: The growth of the mandible, maxilla, zygomatic bone and orbits was measured and the corresponding growth curves were established. Several measurements were strongly correlated with gestational age.


Assuntos
Face , Ultrassonografia Pré-Natal , Gravidez , Feminino , Humanos , Autopsia , Ultrassonografia Pré-Natal/métodos , Face/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Idade Gestacional
2.
Entropy (Basel) ; 24(12)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36554113

RESUMO

To completely comprehend neurodevelopment in healthy and congenitally abnormal fetuses, quantitative analysis of the human fetal brain is essential. This analysis requires the use of automatic multi-tissue fetal brain segmentation techniques. This paper proposes an end-to-end automatic yet effective method for a multi-tissue fetal brain segmentation model called IRMMNET. It includes a inception residual encoder block (EB) and a dense spatial attention (DSAM) block, which facilitate the extraction of multi-scale fetal-brain-tissue-relevant information from multi-view MRI images, enhance the feature reuse, and substantially reduce the number of parameters of the segmentation model. Additionally, we propose three methods for predicting gestational age (GA)-GA prediction by using a 3D autoencoder, GA prediction using radiomics features, and GA prediction using the IRMMNET segmentation model's encoder. Our experiments were performed on a dataset of 80 pathological and non-pathological magnetic resonance fetal brain volume reconstructions across a range of gestational ages (20 to 33 weeks) that were manually segmented into seven different tissue categories. The results showed that the proposed fetal brain segmentation model achieved a Dice score of 0.791±0.18, outperforming the state-of-the-art methods. The radiomics-based GA prediction methods achieved the best results (RMSE: 1.42). We also demonstrated the generalization capabilities of the proposed methods for tasks such as head and neck tumor segmentation and the prediction of patients' survival days.

3.
J Ultrasound Med ; 32(12): 2135-43, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24277896

RESUMO

OBJECTIVES: To create reference charts for fetal age assessment based on fetal sonographic biometry in a population of pregnant women living in the third largest city in Colombia and compare them with charts included in ultrasound machines. METHODS: The study data were obtained from women with a single pregnancy and confirmed gestational age between 12 and 40 completed weeks. All women were recruited specifically for the study, and every fetus was measured only once for biparietal diameter, head circumference, abdominal circumference, and femur length. Polynomial regression models for gestational age as a function of each fetal measurement were fitted to estimate the mean and standard deviation. Percentile curves of gestational age were constructed for each fetal measurement using these regression models. RESULTS: Biparietal diameter, head circumference, abdominal circumference, and femur length were measured in 792 fetuses. Tables and charts of gestational age were derived for each fetal parameter. A cubic polynomial model was the best-fitted regression model to describe the relationships between gestational age and each fetal measurement. The standard deviation was estimated by simple linear regression as a function of each fetal measurement. Comparison of our gestational age mean z scores with those calculated by reference equations showed statistically significant differences (P < .01). CONCLUSIONS: We present a set of reference charts, tables, and formulas for fetal age assessment based on fetal sonographic biometry. The results support the recommendation that these charts and tables could be more appropriate for assessing fetal age in Colombian populations than those currently included in the software of ultrasound machines.


Assuntos
Determinação da Idade pelo Esqueleto/estatística & dados numéricos , Biometria/métodos , Tamanho Corporal , Fêmur/diagnóstico por imagem , Fêmur/embriologia , Idade Gestacional , Ultrassonografia Pré-Natal/estatística & dados numéricos , Determinação da Idade pelo Esqueleto/métodos , Algoritmos , Colômbia/epidemiologia , Feminino , Humanos , Masculino , Gravidez , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia Pré-Natal/métodos
4.
Vet Res Forum ; 13(2): 257-263, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35919850

RESUMO

The aim of this study was to evaluate the correlation between some fetal parameters measured by ultrasonography and fetal age for developing a formula which could be used for estimation of fetal age in Baluchi sheep. Placentome diameter (PD), gestation Sac diameter (GSD), biparietal diameter (BPD), straight crown-rump length (CRL), femural length (FL), occipito-snout diameter (OSD), thoracic diameter (TD) and fetal heart rate (FHR) were measured by transrectal and/or transabdominal ultrasonography. All ewes were synchronized using progesterone sponge for 6 days. On the first day, they received PGF2 and on the last day received 400 IU of equine serum gonadotrophin (eCG). All of the parameters revealed significant correlation by increasing fetal age. Except for PD, for other values linear regression curve was illustrated. BPD (between 36 - 96 days) (R2 = 0.961), CRL (R2 = 0.935), FL (R2 = 0.950), OSD (R2 = 0.981), TD (R2 = 0.975) showed high correlation with fetal age (p < 0.001). Moderate correlation was calculated for FHR (p < 0.001, R2 = 0.883). Low correlations were assessed by measurement of GSD (p = 0.018, R2 = 0.318), BPD (between 96-138 days; p = 0.038, R2 = 0.29) and PD represented the significant non-linear correlation with age (p < 0.001), maximum correlation was assessed by measurement of mean placentome wall diameter. In conclusion, OSD was recommended as the best parameter for estimating of gestational age between days 36 - 109 in Baluchi sheep because of the lowest residuals, the highest correlation coefficient and wide period of availability for imaging in gestation.

5.
Forensic Sci Int ; 266: 587.e1-587.e10, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27289563

RESUMO

Metric standards are presented for the estimation of fetal age at the time of death in the Mexican population. To obtain these standards, both metric and radiological studies were conducted on 97 fetuses and complete stillborn infants of both sexes, phenotypically normal between 10 and 38 weeks of morphological age. All the fetuses used were the product of spontaneous abortions in Mexico City between 1990 and 2000. Equations were obtained by calibrating quadratic linear regression models adjusted for the diaphyseal length of the humerus, radius, ulna, femur, tibia and fibula, characterized as the most adequate indicators to represent the growth of long bones in this age group, and verified by the evaluation of the model assumptions and the coefficient of determination (R(2)). To conclude, these models facilitate a more precise prediction in fetuses of the Mexican population, constituting the first metric standards of their type at a national level.


Assuntos
Osso e Ossos/anatomia & histologia , Diáfises/anatomia & histologia , Feto/anatomia & histologia , Idade Gestacional , Aborto Espontâneo , Osso e Ossos/diagnóstico por imagem , Diáfises/diagnóstico por imagem , Feminino , Morte Fetal , Feto/diagnóstico por imagem , Humanos , Modelos Lineares , Masculino , México , Gravidez , Grupos Raciais , Reprodutibilidade dos Testes
6.
Forensic Sci Int ; 248: 188.e1-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25661492

RESUMO

Little is understood about the age-related changes in the petrous part of the temporal bone in fetal life. The purposes of this study were to examine documented skeletal remains of Japanese fetuses, to measure the length of the petrous part, and to develop diagnostic standards for fetal age-at-death estimation that could be applied to poorly preserved skeletons. The results indicated that it is possible to use a regression equation to estimate age at death directly from the length of the petrous part of the temporal bone. The application of the present method to a different population led to a fetal age-at-death estimation with an error of less than 1 month. We also used the Bayesian estimation, which yielded posterior probabilities of age, conditional on being of a particular length of the petrous part. The reference table of estimated gestational age may provide an easy-to-use indicator of the fetal age at death. In conclusion, measurement of the petrous part of the temporal bone may offer a new methodological basis for forensic and bioarchaeological diagnoses of fetuses.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Morte Fetal , Idade Gestacional , Osso Petroso/anatomia & histologia , Povo Asiático , Feminino , Antropologia Forense , Humanos , Recém-Nascido , Japão , Funções Verossimilhança , Masculino , Gravidez , Análise de Regressão , Reprodutibilidade dos Testes
7.
Theriogenology ; 81(7): 896-900, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24560548

RESUMO

Measurements on the growth process and placental development of the embryo and fetuses of Cavia porcellus were carried out using ultrasonography. Embryo, fetus, and placenta were monitored from Day 15 after mating day to the end of gestation. Based on linear and quadratic regressions, the following morphometric analysis showed a good indicator of the gestational age: placental diameter, biparietal diameter, renal length, and crown rump. The embryonic cardiac beat was first detected at an average of 22.5 days. The placental diameter showed constant increase from beginning of gestation then remained to term and presented a quadratic correlation with gestational age (r(2) = 0.89). Mean placental diameter at the end of pregnancy was 3.5 ± 0.23 cm. By Day 30, it was possible to measure biparietal diameter, which followed a linear pattern of increase up to the end of gestation (r(2) = 0.95). Mean biparietal diameter in the end of pregnancy was 1.94 ± 0.03 cm. Kidneys were firstly observed on Day 35 as hyperechoic structures without the distinction of medullar and cortical layers, thus the regression model equation between kidney length and gestational age presents a quadratic relationship (r(2) = 0.7). The crown rump presented a simple linear growth, starting from 15 days of gestation, displaying a high correlation with the gestational age (r(2) = 0.9). The offspring were born after an average gestation of 61.3 days. In this study, we conclude that biparietal diameter, placental diameter, and crown rump are adequate predictive parameters of gestational age in guinea pigs because they present high correlation index.


Assuntos
Desenvolvimento Fetal , Cobaias/embriologia , Prenhez , Animais , Feminino , Idade Gestacional , Projetos Piloto , Gravidez , Ultrassonografia Pré-Natal/veterinária
8.
Vet Clin North Am Food Anim Pract ; 29(3): 667-78, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24182442

RESUMO

Veterinarians play an important role in reproductive management of dairy herds across the United States; however, in many cases, their involvement in reproductive management of beef herds has been limited. The reasons for this vary; however, there are ways for veterinarians to become more actively involved in reproductive management of US beef herds. Veterinarians can have an impact on producers' profits by implementing their skills and knowledge to beef heifer development programs. This article provides an overview of the services veterinarians can provide to beef cattle producers that pertain to reproductive management of replacement beef heifers.


Assuntos
Criação de Animais Domésticos/métodos , Bovinos/fisiologia , Reprodução/fisiologia , Medicina Veterinária/métodos , Criação de Animais Domésticos/organização & administração , Animais , Feminino , Carne/provisão & distribuição , Medicina Veterinária/organização & administração
9.
Theriogenology ; 80(6): 609-18, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23830233

RESUMO

The aims of this study were to determine the developmental patterns of some fetal parts to achieve a high accuracy level in the assessment of gestational age and to assess the feasibility and accuracy of ultrasonic prenatal fetal sex assessment in camels. Serial ultrasonographic examinations were carried out on seven pregnant dromedary camels. A total of 329 ultrasonographic examinations were conducted between the second and the 54th weeks of pregnancy. Intrauterine fluid accumulation was detected between the second and third weeks of pregnancy. The embryo proper was noticed between the third and fourth weeks. Organization of the embryo was first observed between the sixth and seventh weeks. Ossification was first detected between the seventh and ninth weeks. The accessibility during the total gestational period was 35/329 (10.6%) for crown-rump length, 35/329 (10.6%) for biparietal diameter, 42/329 (12.8%) for abdominal diameter, 42/329 (12.8%) for ruminal length, and 126/329 (38.3%) for eyeball diameter. A high correlation was found between gestational age and each of the studied parameters (P < 0.0001). The highest correlation was found with the crown-rump length and the biparietal diameter during the first trimester and with the eyeball diameter during the third trimester of pregnancy. The overall accuracy of the ultrasonic prenatal fetal sex assessment was 91.7%. The best window was found during the 11th week of pregnancy. It was concluded that sonographic fetometry can be useful for the evaluation of fetal development, the estimation of gestational age, and the prediction of prenatal fetal sex in camels.


Assuntos
Camelus , Análise para Determinação do Sexo/veterinária , Ultrassonografia Pré-Natal/veterinária , Animais , Camelus/embriologia , Estatura Cabeça-Cóccix , Estudos de Viabilidade , Feminino , Desenvolvimento Fetal , Feto/anatomia & histologia , Masculino , Gravidez , Análise para Determinação do Sexo/métodos
10.
Sultan Qaboos Univ Med J ; 6(2): 47-58, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21748135

RESUMO

OBJECTIVE: Little published research exists in the area of fetal thigh biometry, specifically in the use of the anteriorposterior fetal thigh diameter (APTD). A continuing review of existing practices needs to be coupled with evaluation of alternate or additional methodology. This study evaluated the usefulness and direct correlation of a simple, new method of predicting fetal age by measurement of the anterior-posterior thigh diameter (APTD) in a normal 18-to 28 week pregnancies using two-dimensional sonography. METHODS: This was a quantitative prospective study of 55 patients in the High Level General Hospital, Alberta, Canada. Anterior-posterior thigh diameters (APTD) were sonographically measured and the normal range for each week of pregnancy was determined five times for reliability. RESULTS: Significant correlation was found between (APTD) and fetal age from simple line regression analysis, with >99.9% confidence intervals at each week from 18 to 28 weeks gestation. There was a correlation of 1 mm APTD per 1 week of fetal age. The standard error of estimation was very low at (0.08664) in edition (r>0.9993) and (p < than 0.0001). The residual scatter plots confirmed the APTD validity. CONCLUSION: APTD is a reliable and valid method for assessing fetal age in a normal pregnancy and may be particularly useful when other parameters are unable accurately to predict fetal age. An accurate linear measurement of multiple fetal parameters allows a more complete profile of fetal growth and estimated date of delivery (EDD). APTD may also be useful in identifying fetal growth problems. All of the values of fetal age lie directly on the "best-fit" regression line. Since the coefficient of determination (Rsq) is very high, this model is very effective.

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