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- ItemSomente MetadadadosAssessing repeatability of 3D Doppler indices obtained by static 3D and STIC power Doppler: a combined in-vivo/in-vitro flow phantom study(Wiley-Blackwell, 2013-11-01) Miyague, A. H.; Raine-Fenning, N. J.; Polanski, L.; Martinez, Luís Henrique [UNIFESP]; Araujo Junior, Edward [UNIFESP]; Pavan, T. Z.; Martins, W. P.; Universidade de São Paulo (USP); Ultrasonog & Retraining Med Sch Ribeirao Preto EU; Univ Nottingham; Universidade Federal de São Paulo (UNIFESP)ObjectivesTo compare the variability in vascularization flow index (VFI) seen in serial acquisitions obtained using spatiotemporal image correlation (STIC) and using conventional static three-dimensional (3D) power Doppler (PD), for both in-vitro and in-vivo models, and to evaluate whether the curves formed by VFI values obtained from successive frames' in a STIC dataset are consistent and resemble the waveforms obtained by spectral Doppler analysis.MethodsThe study was divided into two parts: in the first part (the in-vitro model) we scanned a flow phantom, while in the second part (the in-vivo model) we scanned a common carotid artery. Conventional static 3D and STIC-PD datasets were alternately acquired from these two models. VFI values were assessed from 0.38-cm(3) spherical samples of the main flow region in the static 3D datasets and in every frame of the STIC datasets. the variance of the minimum, mean and maximum VFI values from each STIC dataset was compared with the variance of VFI values from the static 3D datasets.ResultsTen static 3D and 10 STIC datasets were acquired from each model. Analysis of the in-vitro and in-vivo models showed a significant reduction in the variance of VFI values obtained using STIC as compared to static datasets. Additionally, we observed that the curves formed by VFI values obtained from successive frames in each STIC dataset were consistent across different datasets and that they resembled the waveforms obtained by spectral Doppler in both models.Conclusions3D-PD indices derived from STIC are more stable than those obtained from conventional static 3D-PD datasets. the curves of VFI throughout a reconstructed cardiac cycle using STIC are repeatable and resemble those obtained by spectral Doppler analysis of the vessel. Copyright (c) 2013 ISUOG. Published by John Wiley & Sons Ltd.
- ItemAcesso aberto (Open Access)Avaliação do comprimento e área do corpo caloso fetal por meio da ultrassonografia tridimensional(Federação Brasileira das Sociedades de Ginecologia e Obstetrícia, 2010-12-01) Visentainer, Milena [UNIFESP]; Araujo Júnior, Edward [UNIFESP]; Rolo, Liliam Cristine [UNIFESP]; Nardozza, Luciano Marcondes Machado [UNIFESP]; Moron, Antonio Fernandes [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)PURPOSE: to establish reference values for the length and area of the fetal corpus callosum between the 20th and 33rd weeks of gestation using three-dimensional ultrasound (3DUS). METHODS: this cross-sectional study involved 70 normal pregnancies with gestational age between 20 and 33 weeks. An Accuvix XQ instrument with a convex volumetric transducer (3 to 5 MHz) was used. To assess the corpus callosum, a transfrontal plane was obtained using the metopic suture as an acoustic window. Length was obtained by measuring the distance between the proximal and distal extremities of the corpus callosum. Area was obtained by manual tracing of the external corpus callosum surface. The means, medians, standard deviations, and maximum and minimum values were calculated for the corpus callosum length and area. Scatter graphs were created to analyze the correlation between corpus callosum length and area and gestational age and biparietal diameter, the quality adjustments was verified according to the determination coefficient (R²). The intraclass correlation coefficient (ICC) was used to assess the intraobserver variability. RESULTS: mean corpus callosum length increased from 21.7 (18.6 - 25.2 mm) to 38.7 mm (32.6 - 43.3 mm) between 20 and 33 weeks of pregnancy, respectively. Mean corpus callosum area increased from 55.2 (41.0 - 80.0 mm²) to 142.2 mm² (114.0 - 160.0 mm²), between 20 to 33 weeks of pregnancy, respectively. There was a strong correlation between corpus callosum length and area and gestational age (R² = 0.7 and 0.7, respectively) and biparietal diameter (R² = 0.7 and 0.6, respectively). Intraobserver variability was appropriate, with an ICC of 0.9 and 0.9 for length and area, respectively. CONCLUSIONS: reference values for corpus callosum length and area were established for fetuses between 20 and 33 weeks gestation. Intraobserver variability was appropriate.
- ItemAcesso aberto (Open Access)Volume do embrião estimado pela ultra-sonografia tridimensional entre a sétima e a décima semana de gestação(Federação Brasileira das Sociedades de Ginecologia e Obstetrícia, 2008-10-01) Bortoletti Filho, João [UNIFESP]; Nardozza, Luciano Marcondes Machado [UNIFESP]; Araujo Júnior, Edward [UNIFESP]; Rôlo, Líliam Cristine; Nowak, Paulo Martin [UNIFESP]; Moron, Antonio Fernandes [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)PURPOSE: to evaluate the embryo's volume (EV) between the seventh and the tenth gestational week, through tridimensional ultrasonography. METHODS: a transversal study with 63 normal pregnant women between the seventh and the tenth gestational week. The ultrasonographical exams have been performed with a volumetric abdominal transducer. Virtual Organ Computer-aided Analysis (VOCAL) has been used to calculate EV, with a rotation angle of 12º and a delimitation of 15 sequential slides. The average, median, standard deviation and maximum and minimum values have been calculated for the EV in all the gestational ages. A dispersion graphic has been drawn to assess the correlation between EV and the craniogluteal length (CGL), the adjustment being done by the determination coefficient (R²). To determine EV's reference intervals as a function of the CGL, the following formula was used: percentile=EV+K versus SD, with K=1.96. RESULTS: CGL has varied from 9.0 to 39.7 mm, with an average of 23.9 mm (±7.9 mm), while EV has varied from 0.1 to 7.6 cm³, with an average of 2.7 cm³ (±3.2 cm³). EV was highly correlated to CGL, the best adjustment being obtained with quadratic regression (EV=0.2-0.055 versus CGL+0.005 versus CGL²; R²=0.8). The average EV has varied from 0.1 (-0.3 to 0.5 cm³) to 6.7 cm³ (3.8 to 9.7 cm³) within the interval of 9 to 40 mm of CGL. EV has increased 67 times in this interval, while CGL, only 4.4 times. CONCLUSIONS: EV is a more sensitive parameter than CGL to evaluate embryo growth between the seventh and the tenth week of gestation.