Browsing by Author "Franco, Pamela"

Now showing 1 - 12 of 12
  • No Thumbnail Available
    Item
    A comparison of phase unwrapping methods in velocity-encoded MRI for aortic flows
    (2023) Locke, Miriam; Labra, Jeremias Esteban Garay; Franco, Pamela; Uribe, Sergio; Bertoglio, Cristobal
    PurposeThe phase of a MRI signal is used to encode the velocity of blood flow. Phase unwrapping artifacts may appear when aiming to improve the velocity-to-noise ratio (VNR) of the measured velocity field. This study aims to compare various unwrapping algorithms on ground-truth synthetic data generated using computational fluid dynamics (CFD) simulations. MethodsWe compare four different phase unwrapping algorithms on two different synthetic datasets of four-dimensional flow MRI and 26 datasets of 2D PC-MRI acquisitions including the ascending and descending aorta. The synthetic datasets are constructed using CFD simulations of an aorta with a coarctation, with different levels of spatiotemporal resolutions and noise. The error of the unwrapped images was assessed by comparison against the ground truth velocity field in the synthetic data and dual-VENC reconstructions in the in vivo data. ResultsUsing the unwrapping algorithms, we were able to remove aliased voxels in the data almost entirely, reducing the L2-error compared to the ground truth by 50%-80%. Results indicated that the best choice of algorithm depend on the spatiotemporal resolution and noise level of the dataset. Temporal unwrapping is most successful with a high temporal and low spatial resolution (& delta;t=30$$ \delta t=30 $$ ms, h=2.5$$ h=2.5 $$ mm), reducing the L2-error by 70%-85%, while Laplacian unwrapping performs better with a lower temporal or better spatial resolution (& delta;t=60$$ \delta t=60 $$ ms, h=1.5$$ h=1.5 $$ mm), especially for signal-to-noise ratio (SNR) 12 as opposed to SNR 15, with an error reduction of 55%-85% compared to the 50%-75% achieved by the Temporal method. The differences in performance between the methods are statistically significant. ConclusionsThe temporal method and spatiotemporal Laplacian method provide the best results, with the spatiotemporal Laplacian being more robust. However, single-Venc$$ {V}_{\mathrm{enc}} $$ methods only situationally and not generally reach the performance of dual-Venc$$ {V}_{\mathrm{enc}} $$ unwrapping methods.
  • No Thumbnail Available
    Item
    Comparison of Improved Unidirectional Dual Velocity-Encoding MRI Methods
    (2023) Franco, Pamela; Ma, Liliana; Schnell, Susanne; Carrillo, Hugo; Montalba, Cristian; Markl, Michael; Bertoglio, Cristobal; Uribe, Sergio
    Background In phase-contrast (PC) MRI, several dual velocity encoding methods have been proposed to robustly increase velocity-to-noise ratio (VNR), including a standard dual-VENC (SDV), an optimal dual-VENC (ODV), and bi- and triconditional methods. Purpose To develop a correction method for the ODV approach and to perform a comparison between methods. Study Type Case-control study. Population Twenty-six volunteers. Field Strength/Sequence 1.5 T phase-contrast MRI with VENCs of 50, 75, and 150 cm/second. Assessment Since we acquired single-VENC protocols, we used the background phase from high-VENC (VENCH) to reconstruct the low-VENC (VENCL) phase. We implemented and compared the unwrapping methods for different noise levels and also developed a correction of the ODV method. Statistical Tests Shapiro-Wilk's normality test, two-way analysis of variance with homogeneity of variances was performed using Levene's test, and the significance level was adjusted by Tukey's multiple post hoc analysis with Bonferroni (P < 0.05). Results Statistical analysis revealed no extreme outliers, normally distributed residuals, and homogeneous variances. We found statistically significant interaction between noise levels and the unwrapping methods. This implies that the number of non-unwrapped pixels increased with the noise level. We found that for beta = VENCL/VENCH = 1/2, unwrapping methods were more robust to noise. The post hoc test showed a significant difference between the ODV corrected and the other methods, offering the best results regarding the number of unwrapped pixels. Data Conclusions All methods performed similarly without noise, but the ODV corrected method was more robust to noise at the price of a higher computational time. Level of Evidence 4 Technical Efficacy Stage 1
  • No Thumbnail Available
    Item
    Comprehensive Assessment of Left Intraventricular Hemodynamics Using a Finite Element Method: An Application to Dilated Cardiomyopathy Patients
    (2021) Franco, Pamela; Sotelo, Julio; Montalba, Cristian; Ruijsink, Bram; Kerfoot, Eric; Nordsletten, David; Mura, Joaquin; Hurtado, Daniel; Uribe, Sergio
    In this paper, we applied a method for quantifying several left intraventricular hemodynamic parameters from 4D Flow data and its application in a proof-of-concept study in dilated cardiomyopathy (DCM) patients. In total, 12 healthy volunteers and 13 DCM patients under treatment underwent short-axis cine b-SSFP and 4D Flow MRI. Following 3D segmentation of the left ventricular (LV) cavity and registration of both sequences, several hemodynamic parameters were calculated at peak systole, e-wave, and end-diastole using a finite element approach. Sensitivity, inter- and intra-observer reproducibility of hemodynamic parameters were evaluated by analyzing LV segmentation. A local analysis was performed by dividing the LV cavity into 16 regions. We found significant differences between volunteers and patients in velocity, vorticity, viscous dissipation, energy loss, and kinetic energy at peak systole and e-wave. Furthermore, although five patients showed a recovered ejection fraction after treatment, their hemodynamic parameters remained low. We obtained several hemodynamic parameters with high inter- and intra-observer reproducibility. The sensitivity study revealed that hemodynamic parameters showed a higher accuracy when the segmentation underestimates the LV volumes. Our approach was able to identify abnormal flow patterns in DCM patients compared to volunteers and can be applied to any other cardiovascular diseases.
  • Thumbnail Image
    Item
    Depression and Antidepressants During Pregnancy: Craniofacial Defects Due to Stem/Progenitor Cell Deregulation Mediated by Serotonin
    (FRONTIERS MEDIA SA, 2021) Sanchez, Natalia; Juarez Balarezo, Jesus; Olhaberry, Marcia; González Oneto, Humberto; Muzard, Antonia; Mardonez, Maria Jesus; Franco, Pamela; Barrera, Felipe; Gaete, Marcia
    Depression is a common and debilitating mood disorder that increases in prevalence during pregnancy. Worldwide, 7 to 12% of pregnant women experience depression, in which the associated risk factors include socio-demographic, psychological, and socioecono
  • No Thumbnail Available
    Item
    Fully Three-Dimensional Hemodynamic Characterization of Altered Blood Flow in Bicuspid Aortic Valve Patients With Respect to Aortic Dilatation: A Finite Element Approach
    (2022) Sotelo, Julio; Franco, Pamela; Guala, Andrea; Dux-Santoy, Lydia; Ruiz-Munoz, Aroa; Evangelista, Arturo; Mella, Hernan; Mura, Joaquin; Hurtado, Daniel E.; Rodriguez-Palomares, Jose F.; Uribe, Sergio
    Background and PurposePrognostic models based on cardiovascular hemodynamic parameters may bring new information for an early assessment of patients with bicuspid aortic valve (BAV), playing a key role in reducing the long-term risk of cardiovascular events. This work quantifies several three-dimensional hemodynamic parameters in different patients with BAV and ranks their relationships with aortic diameter. Materials and MethodsUsing 4D-flow CMR data of 74 patients with BAV (49 right-left and 25 right-non-coronary) and 48 healthy volunteers, aortic 3D maps of seventeen 17 different hemodynamic parameters were quantified along the thoracic aorta. Patients with BAV were divided into two morphotype categories, BAV-Non-AAoD (where we include 18 non-dilated patients and 7 root-dilated patients) and BAV-AAoD (where we include the 49 patients with dilatation of the ascending aorta). Differences between volunteers and patients were evaluated using MANOVA with Pillai's trace statistic, Mann-Whitney U test, ROC curves, and minimum redundancy maximum relevance algorithm. Spearman's correlation was used to correlate the dilation with each hemodynamic parameter. ResultsThe flow eccentricity, backward velocity, velocity angle, regurgitation fraction, circumferential wall shear stress, axial vorticity, and axial circulation allowed to discriminate between volunteers and patients with BAV, even in the absence of dilation. In patients with BAV, the diameter presented a strong correlation (> |+/-0.7|) with the forward velocity and velocity angle, and a good correlation (> |+/-0.5|) with regurgitation fraction, wall shear stress, wall shear stress axial, and vorticity, also for morphotypes and phenotypes, some of them are correlated with the diameter. The velocity angle proved to be an excellent biomarker in the differentiation between volunteers and patients with BAV, BAV morphotypes, and BAV phenotypes, with an area under the curve bigger than 0.90, and higher predictor important scores. ConclusionsThrough the application of a novel 3D quantification method, hemodynamic parameters related to flow direction, such as flow eccentricity, velocity angle, and regurgitation fraction, presented the best relationships with a local diameter and effectively differentiated patients with BAV from healthy volunteers.
  • Thumbnail Image
    Item
    Guided web app intervention for reducing symptoms of depression in postpartum women: Results of a feasibility randomized controlled trial
    (2024) Franco, Pamela; Olhaberry, Marcia; Kelders, Saskia; Muzard, Antonia; Cuijpers, Pim
    Background: Chile faces a significant postpartum depression prevalence and treatment gap, necessitating accessible interventions. While cognitive-behavioral internet-based interventions have proven effective in highincome countries, this field is underdeveloped in Chile. Based on the country 's widespread use of digital technology, a guided 8-week cognitive-behavioral web app intervention named " Mam a, te entiendo " was developed. Objective: This study aimed to assess the acceptability and feasibility of " Mam a, te entiendo ", for reducing depressive symptomatology in postpartum women. Methods: Sixty-five postpartum women with minor or major depression were randomly assigned to either intervention or waitlist. Primary outcomes centered on study feasibility, intervention feasibility, and acceptability. Semi-structured interviews with a sub-sample enriched the understanding of participants ' experiences. Secondary outcomes included mental health variables assessed at baseline, post-intervention, and 1-month follow-up. Results: Chilean women displayed great interest in the intervention. 44.8 % of participants completed the intervention. Participants reported high satisfaction and engagement levels, with interviewees highlighting the value of the intervention 's content, exercises, and therapist 's feedback. However, preliminary efficacy analysis didn 't reveal a significant interaction between group and time for outcome measures. Discussion: This research represents a pioneering effort in Chile to evaluate an internet-based intervention for postpartum depression symptoms. The demonstrated feasibility and acceptability highlight the potential of integrating technology -driven approaches into mental health interventions. However, the intervention did not demonstrate superiority, as both groups exhibited similar positive progress in several outcomes. Therefore, the following research phase should involve a larger and more diverse sample to assess the intervention 's effectiveness, identify influencing factors, and determine the individuals who benefit the most.
  • No Thumbnail Available
    Item
    "How it is said": Analyses of WhatsApp communications in a postpartum depression preventive intervention
    (2024) Fernandez, Olga; Perez, J. Carola; Alamo, Nicolle; Fernandez, Sofia; Franco, Pamela; Coo, Soledad; Garcia, M. Ignacia; Aravena, Marcela
    Introduction: "m-What Were We Thinking" (m-WWWT) is an m-health, intervention oriented to prevent symptoms of postpartum depression and anxiety in first-time mothers. Mothers receive psychoeducation and socioemotional support through written communication via text-messaging (i.e., WhatsApp) with the program counsellor. Although the use of m-health interventions targeting mental health has increased, the form/style of communication through text messages between participants and program counsellors has been understudied. Objective: The aim was to describe the formal structure of the communication (Basic Forms) and the communicational intentions (Communicative Intentions) used in the messages sent by the counsellor and to determine if these are related to the post-intervention outcomes. Methods: 438 text messages sent by the counsellor to 53 first-time mothers (M = 25.32 years, SD = 4.23) who participated in the m-WWWT intervention were analyzed. The Therapeutic Activity Coding System was used to capture the communication as a "Communicative Action". Results: The study highlighted the counsellor's frequent use of the "assertion" communicative form (82%) and attuned communicative intentions (52%) and explored (39%) in her messages. The attractors of communication were "assert to attune" and "assert to explore", indicating an empathetic and informative communication style. With respect to their relationship with the intervention outcome, only "assert to explore" messages were positively related to maternal self-efficacy increases. The number of messages was not associated with participants' characteristics at baseline, except for educational level. Discussion: Our results show the relevance of combining the delivery of information with a communication style that allows the counsellor to connect with the specific needs and emotional tone of the participants.
  • Thumbnail Image
    Item
    Identification of hemodynamic biomarkers for bicuspid aortic valve induced aortic dilation using machine learning
    (2022) Franco, Pamela; Sotelo, Julio; Guala, Andrea; Dux-Santoy, Lydia; Evangelista, Arturo; Rodriguez-Palomares, Jose; Mery Quiroz, Domingo Arturo; Salas, Rodrigo; Uribe, Sergio
  • Thumbnail Image
    Item
    Parental personality traits and emotion regulation: Its relationship with infants\' socioemotional development during the perinatal period
    (2023) Muzard, Antonia; Olhaberry Huber, Marcia; Nuñez, Catalina; Vaccarezza Schurmann, Stephanie; Franco, Pamela; Morán, Javier; Sieverson Raddatz, Catalina; León, María José; Apter, Gisele
    Socioemotional development is central throughout life, and it unfolds in an interpersonal context in which each significant caregiver has an impact, particularly during infancy. However, only a relatively small number of studies have investigated associations between mothers and fathers' personality and emotional characteristics with their infant's socioemotional development during the perinatal period. Therefore, the present article examines the relationship between maternal and paternal personality traits and emotion regulation difficulties during the prenatal period with offspring's socioemotional development. This was a non-experimental and longitudinal study that included a community sample of 55 mother-father-baby triads. Parental assessments were carried out between the second and third trimester of pregnancy, and baby's socio-emotional development was assessed during their 2nd month after birth. Results evidenced differences between maternal and paternal personality traits and emotion regulation difficulties during the perinatal period as well as distinct contributions on infant's socioemotional development.
  • No Thumbnail Available
    Item
    Psychological treatment of perinatal depression: a meta-analysis
    (2023) Cuijpers, Pim; Franco, Pamela; Ciharova, Marketa; Miguel, Clara; Segre, Lisa; Quero, Soledad; Karyotaki, Eirini
    Background. Depression during pregnancy and after the birth of a child is highly prevalent and an important public health problem. Psychological interventions are the first-line treatment and, although a considerable number of randomized trials have been conducted, no recent comprehensive meta-analysis has evaluated treatment effects.
  • Thumbnail Image
    Item
    The impact of COVID-19 on experiences of pregnancy and/or early parenting in Chile
    (WILEY, 2021) Olhaberry, Marcia; Sieverson, Catalina; Franco, Pamela; Romero, Macarena; Tagle, Trinidad; Iribarren, Daniela; Honorato, Carolina; Muzard, Antonia
    The unprecedented COVID-19 pandemic has impacted families' mental health around the globe. In June 2020, 1163 parents of high (43%), middle (47%), and low socioeconomic status (SES) (10%) participated in an online survey developed to explore how daily life changes and restrictions that came with COVID-19 affected the experiences of pregnancy and/or parenting children under the age of 5 in Chile. The survey's design had an exploratory and descriptive scope, with a mix of qualitative and quantitative questions. With the aim of exploring differences before and after COVID-19, two time periods were established, and the 47-item questionnaire covered participants' sociodemographic information, support networks, health concerns, mood changes, self-regulation, adult and children's perceived well-being, parental competencies and parents' perceptions of the unborn baby and/or their children's needs. The results relative to retrospective reporting of pre-pandemic levels, showed an increase in children's crying and tantrums as well as in parental irritability and sadness. Additionally, decreases in the ability to calm down and sleep quality in both parents and children were identified. Finally, at a qualitative level, COVID-19 stands out both as an opportunity to get to know their children better and as a stressor related to parental burn-out and discomfort.
  • Thumbnail Image
    Item
    Web-based interventions for depression in individuals with diabetes : review and discussion
    (2018) Franco, Pamela; Gallardo Zanetta, Ana María; Urtubey, Xavier