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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Real-time three-dimensional ultrasound in obstetric application. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Conotruncal anomalies are the leading causes of cyanotic congenital heart disease. We attempted to use live xPlane imaging of ductal arch view and in-plane view of IVS to screen the fetal conotruncal anomalies in 200 fetuses. There were 152 normal cases, 25 conotruncal anomalies and 23 other types of fetal CHDs were involved in this study. The visualization rate of the normal ductal arch view and in-plane view of IVS with live xPlane imaging was 100% (152/152), 100% (152/152) in normal cases, 8% (2/25), 12% (3/25) in conotruncal anomalies and 69.7% (16/23), 73.9% (17/23) in non-conotruncal CHDs, respectively. The visualization rate of abnormal ductal arch and in-plane view in conotruncal anomalies was much higher than that in non-conotruncal anomalies (P<0.001). Therefore, it may be a useful tool for the assessment and diagnosis of fetal conotruncal anomalies. / In conclusion, real-time 3DE is a novel and promising technique to perform the prenatal examination, both the fetal heart and other system. It represents the future of 3D ultrasound and will become a useful tool for prenatal screening and diagnosis. / This thesis summarized real-time 3D ultrasound in obstetric application. With the introduction of matrix transducer, 3D scanning the fetus in real time became available. / We attempted to use real-time 3D ultrasound in obstetrics outside the fetal heart. We evaluated the feasibility of using real-time 3D ultrasound to assist in obtaining a true midsagittal view in first trimester. Eight sonographers, including FMF-certified and non FMF-certified operators, were asked to perform ultrasound examinations on five patients and forty patients were examined in total. It showed that the deviation from true midsagittal view was reduced greatly with the guidance of live xPlane imaging. Real-time 3D ultrasound can improve the accuracy of acquisition of a defined sonographic plane, and reduce the difference in performance between operators who are formally certified or not. / We demonstrated a novel method to visualize the aortic and ductal arch with live xPlane imaging. The visualization rate is 100%. Ductal arch view can be visualized by placing the reference line through pulmonary artery and descending aorta and aortic arch view can be acquired by putting the reference line along the transverse view of aortic arch and descending aorta on the 3VT view with live xPlane imaging. Therefore, live xPlane imaging is an easy and feasible method for real-time imaging of the ductal and aortic arch. / We explored the feasibility to perform the fetal heart screening using real-time 3DE with live xPlane imaging. We developed and reported the methodology of acquiring and examining the screening planes of the fetal heart with live xPlane imaging. The procedure was simple and straight. When performing the fetal heart screening with live xPlane imaging, we just need display the apical four-chamber view and mid-sagittal view of fetal upper thorax and other thing could be done by moving the reference line. The overall detection of four cardiac screen planes can reach 100%. / We explored to evaluate the entire fetal IVS with both live xPlane imaging and live 3D imaging. We can successfully assess the entire IVS in most fetuses (153/154). We also compared the images acquired by real-time 3DE and STIC in this thesis. It showed that less motion artifact encounters with real-time 3DE and the image quality of real-time 3DE is similar to STIC volume acquired from the sagittal view (P>0.05) and superior to STIC volume from the four-chamber view (P<0.05). Therefore, real-time 3DE can be used to display the lateral view of the fetal IVS, and potentially may be a useful tool for the assessment and diagnosis of fetal VSDs. / Xiong, Yi. / Adviser: Tzekin Lau. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 116-138). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
2

Rubéola na gestação: repercussões sobre o produto conceptual. / Rubella in pregnancy: effects on the fetus and developing child

Pedreira, Denise Araujo Lapa 02 December 1998 (has links)
OBJETIVOS: Avaliar os efeitos da rubéola durante a gestação, sobre o feto, o recém-nascido e a criança. CASUÍSTICA E MÉTODO: Analisamos 35 gestantes com suspeita de rubéola que foram divididas em dois grupos. Grupo 1: 15 pacientes que apresentaram quadro clínico com comprovação sorológica. Grupo2: 20 pacientes com IgM positiva na rotina pré-natal, na ausência de quadro clínico. O seguimento ultrasonográfico mensal foi realizado em todas as pacientes e as do grupo 1 foram encaminhadas também para propedêutica invasiva. Foram também realizadas a ecocardiografia fetal e a Dopplervelocimetria. As placentas foram submetidas a exame anátomo-patológico. Os recém-nascidos vivos foram avaliados através de exame clínico e sorológico, além do potencial evocado auditivo, ultra-sonografia de crânio, fundo de olho e ecocardiografia pós-natal. RESULTADOS: No grupo 1: a infecção fetal ocorreu em 9 casos, sendo que o risco de transmissão vertical entre 2 a 14 semanas foi de 64,9%. A malformação ocorreu em 37,5% dos infectados. A ultrasonografia revelou crescimento intra-uterino retardado simétrico em todos os fetos infectados que atingiram o terceiro trimestre, tendo se iniciado, em média com 25,1 semanas. A cordocentese foi realizada em 9 pacientes e, todos os casos infectados, apresentavam IgM positiva e eritroblastose no sangue de cordão. A PCR no líquido amniótico foi positiva em todos os 3 casos em que ela foi realizada. 50% das placentas dos fetos infectados apresentava sinais sugestivos de infecção viral. A idade gestacional média do parto entre os infectados foi de 33,8 semanas e o peso médio ao nascimento foi 1365,6g.Todos os 6 nascidos-vivos infectados foram classificados como pequenos para a idade gestacional e apresentaram disacusia. A sobrevida entre os infectados, num seguimento pós-natal médio de 35,2 meses, foi de 62,5%. No grupo 2: a infecção não foi comprovada em nenhum dos recém-nascidos vivos, porém em um caso pudemos demonstrar a infecção congênita pelo vírus de Epstein-Barr. CONCLUSÕES: A transmissão vertical da rubéola no primeiro trimestre parece poder variar entre as populações, bem como a presença dos defeitos associados à infecção. Tanto o diagnóstico invasivo, como o ultrasonográfico apresentaram boa sensibilidade e especificidade. Pudemos estabelecer o padrão de crescimento fetal associado à infecção. A presença isolada de IgM positiva para rubéola na gestação não teve boa correlação com a presença de infecção neonatal, porém pode se associar à presença de outras infecções congênitas. / OBJECTIVES: Our aim was to analyse rubella effects on the fetus, new-born and child. MATERIAL AND METHODS: We analysed 35 patients with suspicious rubella during pregnancy. According to presence or absence of symptoms they were divided in two groups. Group 1: 15 patients presenting rash in which serology was positive. Grupo2: 20 symptomless patients found to have positive IgM during routine prenatal care. Monthly ultrasonographic evaluation was accomplished in all patients and in group 1 they were also offered prenatal invasive testing. Fetal echocardiography and Dopplers were performed. After birth, the placentas were submitted to pathological examination. The liveborn babies had clinical and serological examination. Auditory tests, brain scan, fundoscopy and postnatal echocardiography were also performed. RESULTS: In group 1: fetal infection occurred in 9 cases and vertical transmission between 2 to 14 weeks was 64,9%. Malformation was present in 37,5% of infected cases. Ultrasound revealed symmetrical intra-uterine growth retardation in all infected fetuses that reached the third trimester, and started around 25,1 weeks. Cordocentesis was accomplished in 9 cases and all the infected ones, presented positive IgM and erythroblastosis in cord blood. PCR in the amniotic fluid was positive in all 3 cases it was performed. 50% of the infected fetuses placentas presented signs of viral infection. The average gestacional age of delivery among infected cases was 33,8 weeks and medium birth weight was 1365,6g. All 6 liveborn infected babies were small for gestacional age and presented deafness. Survival among infected cases was 62,5%, medium follow-up was 35,2 months. In group 2: the infection was not demonstrated in any of neonates, although we could demonstrate a congenital infection caused by the Epstein-Barr virus. CONCLUSIONS: Vertical transmission of the rubella in the first trimester seems to vary among different populations, as well as the presence of the associated defects in the new-born. Invasive diagnosis and ultrasonographic follow-up presented good sensitivity and specificity. We could establish the pattern of fetal grown associated to the infection. The isolated presence of a positive rubella IgM in pregnancy did not correlated with congenital rubella, but it can be related to other congenital infections.
3

Rubéola na gestação: repercussões sobre o produto conceptual. / Rubella in pregnancy: effects on the fetus and developing child

Denise Araujo Lapa Pedreira 02 December 1998 (has links)
OBJETIVOS: Avaliar os efeitos da rubéola durante a gestação, sobre o feto, o recém-nascido e a criança. CASUÍSTICA E MÉTODO: Analisamos 35 gestantes com suspeita de rubéola que foram divididas em dois grupos. Grupo 1: 15 pacientes que apresentaram quadro clínico com comprovação sorológica. Grupo2: 20 pacientes com IgM positiva na rotina pré-natal, na ausência de quadro clínico. O seguimento ultrasonográfico mensal foi realizado em todas as pacientes e as do grupo 1 foram encaminhadas também para propedêutica invasiva. Foram também realizadas a ecocardiografia fetal e a Dopplervelocimetria. As placentas foram submetidas a exame anátomo-patológico. Os recém-nascidos vivos foram avaliados através de exame clínico e sorológico, além do potencial evocado auditivo, ultra-sonografia de crânio, fundo de olho e ecocardiografia pós-natal. RESULTADOS: No grupo 1: a infecção fetal ocorreu em 9 casos, sendo que o risco de transmissão vertical entre 2 a 14 semanas foi de 64,9%. A malformação ocorreu em 37,5% dos infectados. A ultrasonografia revelou crescimento intra-uterino retardado simétrico em todos os fetos infectados que atingiram o terceiro trimestre, tendo se iniciado, em média com 25,1 semanas. A cordocentese foi realizada em 9 pacientes e, todos os casos infectados, apresentavam IgM positiva e eritroblastose no sangue de cordão. A PCR no líquido amniótico foi positiva em todos os 3 casos em que ela foi realizada. 50% das placentas dos fetos infectados apresentava sinais sugestivos de infecção viral. A idade gestacional média do parto entre os infectados foi de 33,8 semanas e o peso médio ao nascimento foi 1365,6g.Todos os 6 nascidos-vivos infectados foram classificados como pequenos para a idade gestacional e apresentaram disacusia. A sobrevida entre os infectados, num seguimento pós-natal médio de 35,2 meses, foi de 62,5%. No grupo 2: a infecção não foi comprovada em nenhum dos recém-nascidos vivos, porém em um caso pudemos demonstrar a infecção congênita pelo vírus de Epstein-Barr. CONCLUSÕES: A transmissão vertical da rubéola no primeiro trimestre parece poder variar entre as populações, bem como a presença dos defeitos associados à infecção. Tanto o diagnóstico invasivo, como o ultrasonográfico apresentaram boa sensibilidade e especificidade. Pudemos estabelecer o padrão de crescimento fetal associado à infecção. A presença isolada de IgM positiva para rubéola na gestação não teve boa correlação com a presença de infecção neonatal, porém pode se associar à presença de outras infecções congênitas. / OBJECTIVES: Our aim was to analyse rubella effects on the fetus, new-born and child. MATERIAL AND METHODS: We analysed 35 patients with suspicious rubella during pregnancy. According to presence or absence of symptoms they were divided in two groups. Group 1: 15 patients presenting rash in which serology was positive. Grupo2: 20 symptomless patients found to have positive IgM during routine prenatal care. Monthly ultrasonographic evaluation was accomplished in all patients and in group 1 they were also offered prenatal invasive testing. Fetal echocardiography and Dopplers were performed. After birth, the placentas were submitted to pathological examination. The liveborn babies had clinical and serological examination. Auditory tests, brain scan, fundoscopy and postnatal echocardiography were also performed. RESULTS: In group 1: fetal infection occurred in 9 cases and vertical transmission between 2 to 14 weeks was 64,9%. Malformation was present in 37,5% of infected cases. Ultrasound revealed symmetrical intra-uterine growth retardation in all infected fetuses that reached the third trimester, and started around 25,1 weeks. Cordocentesis was accomplished in 9 cases and all the infected ones, presented positive IgM and erythroblastosis in cord blood. PCR in the amniotic fluid was positive in all 3 cases it was performed. 50% of the infected fetuses placentas presented signs of viral infection. The average gestacional age of delivery among infected cases was 33,8 weeks and medium birth weight was 1365,6g. All 6 liveborn infected babies were small for gestacional age and presented deafness. Survival among infected cases was 62,5%, medium follow-up was 35,2 months. In group 2: the infection was not demonstrated in any of neonates, although we could demonstrate a congenital infection caused by the Epstein-Barr virus. CONCLUSIONS: Vertical transmission of the rubella in the first trimester seems to vary among different populations, as well as the presence of the associated defects in the new-born. Invasive diagnosis and ultrasonographic follow-up presented good sensitivity and specificity. We could establish the pattern of fetal grown associated to the infection. The isolated presence of a positive rubella IgM in pregnancy did not correlated with congenital rubella, but it can be related to other congenital infections.
4

"Estudo dopplervelocimétrico das artérias uterinas em três períodos de gestações normais" / Study of the uterine arteries Doppler ultrasound in three periods of normal pregnancies

Sakamoto, Kathia 02 October 2003 (has links)
Estudo longitudinal, prospectivo, comparativo de avaliação dopplervelocimétrica das artérias uterinas direita e esquerda em 37 gestantes normais em três períodos da gestação, acompanhadas na Clínica Obstétrica do HCFMUSP. Análise da relação S/D, índice de pulsatilidade e índice de resistência, relação com o número de incisuras e com posição da placenta. Foi observada redução nos valores dos índices durante a gestação. A relação S/D AUTE com placenta a direita apresentou média superior. A incidência de incisura foi maior no período entre a 16ª e a 24ª semana de gestação. A análise da relação entre os índices dopplervelocimétricos e a presença de incisura não teve resultados significativos / Prospective, longitudinal, comparative study of Doppler evaluation of the right and left uterine arteries of 37 healthy women with singleton pregnancies, performed in three periods of pregnancy, at the Pre-Natal Care Unit HCFMUSP. S/D ratio, pulsatility index and resistance index, number of notches and placental position were analysed. A decrease in the indices was observed with advancing gestation. When placenta was on the right side, the left uterine artery S/D ratio showed increased mean values. The incidence of uterine notch was higher between the 16th and 24th week of gestation in both arteries. No correlation was found between the presence of uterine notch and the placental position
5

"Estudo dopplervelocimétrico das artérias uterinas em três períodos de gestações normais" / Study of the uterine arteries Doppler ultrasound in three periods of normal pregnancies

Kathia Sakamoto 02 October 2003 (has links)
Estudo longitudinal, prospectivo, comparativo de avaliação dopplervelocimétrica das artérias uterinas direita e esquerda em 37 gestantes normais em três períodos da gestação, acompanhadas na Clínica Obstétrica do HCFMUSP. Análise da relação S/D, índice de pulsatilidade e índice de resistência, relação com o número de incisuras e com posição da placenta. Foi observada redução nos valores dos índices durante a gestação. A relação S/D AUTE com placenta a direita apresentou média superior. A incidência de incisura foi maior no período entre a 16ª e a 24ª semana de gestação. A análise da relação entre os índices dopplervelocimétricos e a presença de incisura não teve resultados significativos / Prospective, longitudinal, comparative study of Doppler evaluation of the right and left uterine arteries of 37 healthy women with singleton pregnancies, performed in three periods of pregnancy, at the Pre-Natal Care Unit HCFMUSP. S/D ratio, pulsatility index and resistance index, number of notches and placental position were analysed. A decrease in the indices was observed with advancing gestation. When placenta was on the right side, the left uterine artery S/D ratio showed increased mean values. The incidence of uterine notch was higher between the 16th and 24th week of gestation in both arteries. No correlation was found between the presence of uterine notch and the placental position

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