Jan Deprest

Universitair Ziekenhuis Leuven, Louvain, Flemish, Belgium

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Publications (705)2162.98 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the effect of a newly developed training curriculum on performance of fetoscopic laser surgery for twin-twin transfusion syndrome (TTTS) using an advanced high-fidelity simulator model. Ten novices were randomized to receive verbal instructions and skills training using the simulator (study group, n = 5) or no training (control group, n = 5). Both groups were evaluated with a pre-training test and post-training test. Assessment was performed by two independent observers and compromised a 52-item checklist for surgical performance (SP score), measurement of procedure time and number of anastomoses missed. Face validity and educational value of the simulator were assessed using a questionnaire. Eleven experts set the benchmark level of performance. Both groups showed an improvement in SP score compared to the pre-training test. The simulator-trained group significantly outperformed the control group with a median SP score of 28 (54%) in the pre-test and 46 (88%) in the post-test versus 25 (48%) and 36 (69%) (p = 0.008). Procedure time decreased 11 min in the study group versus 1 min in the control group; to 32 min versus 38 min, respectively (p = 0.69). The number of missed anastomoses was not different between groups (1 versus none). Feedback provided by the participants indicated that training on the simulator was perceived as a useful educational activity. Proficiency-based simulator training improves performance on surgical performance score for fetoscopic laser therapy. Despite the small sample size of this study practice on a simulator is recommended before trainees carry out laser therapy for TTTS in pregnant women. This article is protected by copyright. All rights reserved.
    Ultrasound in Obstetrics and Gynecology 06/2015; DOI:10.1002/uog.14916 · 3.14 Impact Factor
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    ABSTRACT: The aim of this study is to evaluate the prevalence of veno-venous (VV) anastomoses in a large cohort of monochorionic (MC) twin placentas with twin-twin transfusion syndrome (TTTS) compared to a control group of MC placentas without TTTS. All TTTS placentas not treated with fetoscopic laser surgery (TTTS group) and examined at five international fetal therapy centers were included in this study and compared with a control group of MC placentas without TTTS (non-TTTS group). MC placentas were routinely injected with colored dye. We recorded the presence of VV and arterio-arterial (AA) anastomoses. A total of 414 MC placentas were included in this study (TTTS group, n = 106; non-TTTS group, n = 308). The prevalence of VV anastomoses was significantly higher in the TTTS group than in the non-TTTS group, 36% (38/106) and 25% (78/308), respectively (p = .04; odds ratio (OR) 1.65; 95% confidence interval (CI): 1.03-2.64). In the subgroup of MC placentas without AA anastomoses, the prevalence of VV anastomoses in the TTTS group and non-TTTS group was 32% (18/57) and 8% (2/25), respectively (p = .03; OR: 5.31; 95% CI: 1.13-24.98). VV anastomoses are detected more frequently in TTTS placentas than in MC placentas without TTTS and may thus play a role in the development of TTTS. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Placenta 05/2015; DOI:10.1016/j.placenta.2015.05.014 · 3.29 Impact Factor
  • Materials 05/2015; 8(5):2794-2808. DOI:10.3390/ma8052794 · 1.88 Impact Factor
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    ABSTRACT: The properties of meshes used in reconstructive surgery affect the host response and biomechanical characteristics of the grafted tissue. Whereas durable synthetics induce a chronic inflammation, biological grafts are usually considered as more biocompatible. The location of implantation is another determinant of the host response: the vagina is a different environment with specific function and anatomy. Herein, we evaluated a cross-linked acellular collagen matrix (ACM), pretreated by the anti-calcification procedure ADAPT® in a sheep model for vaginal surgery. Ten sheep were implanted with a cross-linked ACM, and six controls were implanted with a polypropylene (PP; 56 g/m2) control. One implant was inserted in the lower rectovaginal septum, and one was used for abdominal wall defect reconstruction. Grafts were removed after 180 days; all graft-related complications were recorded, and explants underwent bi-axial tensiometry and contractility testing. Half of ACM-implanted animals had palpable induration in the vaginal implantation area, two of these also on the abdominal implant. One animal had a vaginal exposure. Vaginal ACMs were 63 % less stiff compared to abdominal ACM explants (p = 0.01) but comparable to vaginal PP explants. Seven anterior vaginal ACM explants showed areas of graft degradation on histology. There was no overall difference in vaginal contractility. Considering histologic degradation in the anterior vaginal implant as representative for the host, posterior ACM explants of animals with degradation had a 60 % reduced contractility as compared to PP (p = 0.048). Three abdominal implants showed histologic degradation; those were more compliant than non-degraded implants. Vaginal implantation with ACM was associated with graft-related complications (GRCs) and biomechanical properties comparable to PP. Partially degraded ACM had a decreased vaginal contractility.
    Gynecological Surgery 05/2015; 12(2). DOI:10.1007/s10397-015-0883-7
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    ABSTRACT: Objective We aimed to systematically review all published pre-clinical research on prenatal medical treatment of pulmonary hypoplasia in congenital diaphragmatic hernia (CDH). Background The neonatal mortality due to isolated CDH remains high. Whether fetal endoscopic tracheal occlusion (FETO) reduces mortality is still to be demonstrated. Therefore more potent preferentially medical therapy would be welcomed. Methods We searched MEDLINE (Pubmed), Embase and the Web of Science including all studies from the earliest date (1951) to December 2013. Article quality was assessed using the modified CAMRADES checklist. Inclusion criteria were those animal studies addressing prenatal medical interventions and principal variables were confirmation of a diaphragmatic defect, lung to body weight ratio (LBWR), formal airway morphometry or DNA/protein content. Results In total 983 articles were identified. Following abstract review, 96 articles were assessed by two authors in agreement with a third for eligibility. Of these, 43 were included in the final analysis. The median number of study quality checklist items (maximum 10) scored was 4 (IQ range: 2–5). Thirty (69.8%) of studies were in the nitrofen rat. The majority were treated with vitamins or glucocorticoids. Single studies reported some improvement in lung morphology with alternative therapies. It was impossible to identify a pattern in animal model selection or creation, mode, time point or duration of treatment and readouts. Only one study reported a sample size calculation. Conclusion Comparison in pre-clinical studies in CDH is challenging due to methodological variation. Agreed standardized methods need to be applied in future investigation of new medical therapies. Pediatr Pulmonol. © 2015 Wiley Periodicals, Inc.
    Pediatric Pulmonology 05/2015; DOI:10.1002/ppul.23206 · 2.30 Impact Factor
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    ABSTRACT: To evaluate the feasibility of tracheo-amniotic shunting in a sheep model for congenital high airway obstruction syndrome. High airway obstruction was induced around day 95 (term = 145 days) in 10 lamb fetuses by tracheal clipping. Five days later, ultrasound-guided tracheoamniotic shunting was done using either the Harrison double-pigtail bladder stent (HS) or a double-basket device (BS). Caesarean section (CS) was done around day 110. At each time point, the cardiothoracic index (CTI) was measured. Lung-to-body weight ratio (LBWR) was calculated at fetal necropsy. The primary endpoint was successful shunting defined as anatomically correct placement and functional airway decompression; the secondary endpoint was survival until CS. Two sheep aborted 3 fetuses after tracheal occlusion. Overall, the median CTI at CS was significantly smaller compared to baseline [0.52 (interquartile range, IQR: 0.52-0.54) vs. 0.58 (IQR: 0.54-0.63); p = 0.01]. In the HS group (n = 4), none of the shunts were correctly positioned. In the BS group (n = 3), there was 1 correct shunt placement; however, this fetus was stillborn. Median LBWR suggested pulmonary overgrowth [0.10 (IQR: 0.08-0.11)]. In our hands, using this model with a long and mobile neck and relative oligohydramnios, tracheoamniotic shunting for airway obstruction has a high failure rate. If further pursued, alternative techniques or different models should be considered. © 2015 S. Karger AG, Basel.
    Fetal Diagnosis and Therapy 04/2015; DOI:10.1159/000381145 · 2.30 Impact Factor
  • European Urology Supplements 04/2015; 14(2):e74. DOI:10.1016/S1569-9056(15)60076-8 · 3.37 Impact Factor
  • European Urology Supplements 04/2015; 14(2):e1005. DOI:10.1016/S1569-9056(15)60993-9 · 3.37 Impact Factor
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    ABSTRACT: Our primary objective was to develop relevant algorithms for quantification of mesh position and 3D shape in magnetic resonance (MR) images. In this proof-of-principle study, one patient with severe anterior vaginal wall prolapse was implanted with an MR-visible mesh. High-resolution MR images of the pelvis were acquired 6 weeks and 8 months postsurgery. 3D models were created using semiautomatic segmentation techniques. Conformational changes were recorded quantitatively using part-comparison analysis. An ellipticity measure is proposed to record longitudinal conformational changes in the mesh arms. The surface that is the effective reinforcement provided by the mesh is calculated using a novel methodology. The area of this surface is the effective support area (ESA). MR-visible mesh was clearly outlined in the images, which allowed us to longitudinally quantify mesh configuration between 6 weeks and 8 months after implantation. No significant changes were found in mesh position, effective support area, conformation of the mesh's main body, and arm length during the period of observation. Ellipticity profiles show longitudinal conformational changes in posterior arms. This paper proposes novel methodologies for a systematic 3D assessment of the position and morphology of MR-visible meshes. A novel semiautomatic tool was developed to calculate the effective area of support provided by the mesh, a potentially clinically important parameter.
    International Urogynecology Journal 03/2015; DOI:10.1007/s00192-015-2681-1 · 2.16 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S103. DOI:10.1016/j.ajog.2014.10.223 · 3.97 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S44-S45. DOI:10.1016/j.ajog.2014.10.109 · 3.97 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S273. DOI:10.1016/j.ajog.2014.10.593 · 3.97 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S171. DOI:10.1016/j.ajog.2014.10.363 · 3.97 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S178-S179. DOI:10.1016/j.ajog.2014.10.383 · 3.97 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S179. DOI:10.1016/j.ajog.2014.10.384 · 3.97 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S324-S325. DOI:10.1016/j.ajog.2014.10.865 · 3.97 Impact Factor
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    ABSTRACT: Objective: To report the results of fetal cystoscopic laser ablation of posterior urethral valves (PUV) in a consecutive series in two referral centers. Methods: Twenty pregnant women with a presumptive isolated PUV were treated with fetal cystoscopy under local anesthesia. Identification and fulguration of the PUV by one or several firing-contacts with diode laser were attempted. Perinatal and long-term outcomes were prospectively recorded. Results: The median gestational age at procedure was 18.1 weeks (range 15.0-25.6), and median operation time was 24 min (range 15-40). Access to the urethra was achieved in 19/20 (95%) cases, and postoperative, normalization of bladder size and amniotic fluid was observed in 16/20 (80%). Overall, there were 9 (45%) terminations of pregnancy and 11 women (55%) delivered a liveborn baby at a mean gestational age of 37.3 (29.1-40.2) weeks. No infants developed pulmonary hypoplasia and all were alive at 15-110 months. Eight (40% of all fetuses, 72.7% of newborns) had normal renal function and 3 (27.3%) had renal failure awaiting renal transplantation. Conclusion: Fetoscopic laser ablation for PUV can achieve bladder decompression and amniotic fluid normalization with a single procedure in selected cases with anyhydramnios. There is still a significant risk of progression to renal failure pre or postnatally. © 2015 S. Karger AG, Basel.
    Fetal Diagnosis and Therapy 01/2015; DOI:10.1159/000367805 · 2.30 Impact Factor
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    ABSTRACT: Objectives Stem cells (SC) can be isolated from amniotic fluid (AF) for a variety of perinatal applications. In view of this we compared different cryopreservation protocols for these AFSCs.Methods We screened seven freezing & thawing protocols using two well-established human AFSC lines: Freezing protocol 1 (FP1): 10% DMSO, FP2: 2.5% DMSO, caspase-inhibitor and catalase, FP3: 5% glycerol, caspase-inhibitor and catalase, FP4: sperm freezing medium, FP5: slow freezing solution, FP6: ethylene glycol, sucrose and ficoll 70 and FP7: vitrification solution. Outcome measures were post-thawing cell viability, recovery, doubling time and mesenchymal stem cell markers. The three best performing protocols were subsequently tested on cells isolated from clinical consecutive freshly harvested amniotic fluid samples from two fetal medicine units.ResultsProtocols 1, 5 and 6 performed significantly better on well characterized cell lines. They performed equally well on cell pellets from freshly harvested amniotic fluid (n=28).Conclusions We identified 3 suitable cryopreservation protocols because of high cell recovery and unchanged stem cell characteristics. Given one of these, the slow freezing solution, is compatible with current Good Manufacturing Practice (GMP)-legislation, it may be ultimately clinically used. This article is protected by copyright. All rights reserved.
    Prenatal Diagnosis 01/2015; 35(5). DOI:10.1002/pd.4556 · 2.51 Impact Factor
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    ABSTRACT: Our objective was to determine the fetal in vivo microRNA signature in hypoplastic lungs of human fetuses with severe isolated congenital diaphragmatic hernia (CDH) and changes in tracheal and amniotic fluid of fetuses undergoing fetoscopic endoluminal tracheal occlusion (FETO) to reverse severe lung hypoplasia due to CDH. We profiled microRNA expression in prenatal human lungs by microarray analysis. We then validated this signature with real-time quantitative polymerase chain reaction in tracheal and amniotic fluid of CDH patients undergoing FETO. We further explored the role of miR-200b using semiquantitative in situ hybridization and immunohistochemistry for TGF-β2 in postnatal lung sections. We investigated miR-200b effects on TGF-β signaling using a SMAD-luciferase reporter assay and Western blotting for phospho-SMAD2/3 and ZEB-2 in cultures of human bronchial epithelial cells. CDH lungs display an increased expression of 2 microRNAs: miR-200b and miR-10a as compared to control lungs. Fetuses undergoing FETO display increased miR-200 expression in their tracheal fluid at the time of balloon removal. Future survivors of FETO display significantly higher miR-200 expression than those with a limited response. miR-200b was expressed in bronchial epithelial cells and vascular endothelial cells. TGF-β2 expression was lower in CDH lungs. miR-200b inhibited TGF-β-induced SMAD signaling in cultures of human bronchial epithelial cells. Human fetal hypoplastic CDH lungs have a specific miR-200/miR-10a signature. Survival after FETO is associated with increased miR-200 family expression. miR-200b overexpression in CDH lungs results in decreased TGF-β/SMAD signaling.
    Annals of Surgery 01/2015; DOI:10.1097/SLA.0000000000001054 · 7.19 Impact Factor
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    ABSTRACT: Objective To determine the bias induced by matching fetuses by gestational age (GA) or by fetal body volume (FBV) when calculating the observed/expected total fetal lung volume (o/e TFLV) in isolated congenital diaphragmatic hernia (CDH). Methods Single-center, retrospective study on archived magnetic resonance (MR) images of isolated CDH fetuses over a 10-year's period. We retrieved the TFLV, GA and o/e TFLVGA, delineated FBV to obtain TFLVFBV. We correlated o/e TFLVFBV and o/e TFLVGA by Bland Altman analysis. All outliers were manually identified to retrieve specific clinical features. Results377 MR examinations from 225 fetuses were identified. The average time spent on FBV measurement was 16.12 ± 4.95 min. Reproducibility of FBV measurement was 0.998 and the interobserver intraclass correlation coefficient was 0.999. FBV was highly correlated with GA (R = 0.94, p < 0.0001). There was a good agreement between o/e TFLVGA or o/e TFLVFBV, with a mean difference = −1.10% and 95%-limits-of-agreement of −8.58 to 6.39. There were no outliers in fetuses that had an o/e TFLV<25%. Discrepancies induced by different methods were more likely in woman with BMI≥25 kg/m2 (+16.49%), fetuses with an estimated fetal weight (EFW)≤10th percentile (+21.33%) or EFW>90th percentile (+14.82%). Conclusions Discrepancies are more likely in fetuses with an abnormal EFW or in overweighted mothers. The clinical relevance of using FBV rather than GA for calculation of the o/e TFLV might be limited, as there was no discrepancy between both methods in fetuses with small lungs (<25%), the group of interest for lung volume assessment.
    Ultrasound in Obstetrics and Gynecology 12/2014; 44(6). DOI:10.1002/uog.13356 · 3.14 Impact Factor

Publication Stats

9k Citations
2,162.98 Total Impact Points


  • 1970–2015
    • Universitair Ziekenhuis Leuven
      • • Department of Gynaecology and obstetrics
      • • Department of Radiology
      Louvain, Flemish, Belgium
  • 1995–2014
    • University of Leuven
      • • Department of Development and Regeneration
      • • Faculty of Medicine
      • • Department of Human Genetics
      Louvain, Flemish, Belgium
    • Universitair Psychiatrisch Centrum KU Leuven
      Cortenberg, Flanders, Belgium
  • 2012
    • University of Sarajevo
      Bosna-Sarai, Federation of Bosnia and Herzegovina, Bosnia and Herzegovina
  • 2008–2012
    • Universitair Ziekenhuis Ghent
      Gand, Flemish, Belgium
    • St. Michael's Hospital
      Toronto, Ontario, Canada
    • Leiden University
      Leyden, South Holland, Netherlands
    • University of Maryland, Baltimore
      Baltimore, Maryland, United States
  • 1995–2012
    • Catholic University of Louvain
      Лувен-ла-Нев, Walloon, Belgium
  • 2010
    • Cliniques Universitaires Saint-Luc
      • Division of Obstetrics
      Bruxelles, Brussels Capital Region, Belgium
  • 2009
    • Leiden University Medical Centre
      • Department of Neonatology
      Leiden, South Holland, Netherlands
  • 2007–2009
    • Hospital Clínic de Barcelona
      • Servicio de Medicina Materno Fetal
      Barcino, Catalonia, Spain
    • King's College Hospital NHS Foundation Trust
      Londinium, England, United Kingdom
    • University of Amsterdam
      Amsterdamo, North Holland, Netherlands
  • 2006–2007
    • King's College London
      • Division of Asthma, Allergy and Lung Biology
      Londinium, England, United Kingdom
    • University of Glasgow
      Glasgow, Scotland, United Kingdom
    • University of Cincinnati
      Cincinnati, Ohio, United States
    • University of Texas Health Science Center at San Antonio
      • Department of Obstetrics and Gynecology
      San Antonio, Texas, United States
  • 2005
    • Maastricht University
      Maestricht, Limburg, Netherlands
    • Technische Universität München
      München, Bavaria, Germany
    • Brown University
      Providence, Rhode Island, United States
    • University of Zurich
      Zürich, Zurich, Switzerland
    • University Hospital Vall d'Hebron
      Barcino, Catalonia, Spain
  • 2001–2005
      Ayrivan, Yerevan, Armenia
  • 2004
    • Hannover Medical School
      Hanover, Lower Saxony, Germany
    • University Medical Center Hamburg - Eppendorf
      Hamburg, Hamburg, Germany
    • University of Geneva
      • Department of Obstetrics and Gynaecology
      Genève, Geneva, Switzerland
    • Wayne State University
      • Department of Obstetrics and Gynecology
      Detroit, Michigan, United States
    • University of Massachusetts Boston
      Boston, Massachusetts, United States
  • 2003
    • Fukushima Medical University
      Hukusima, Fukushima, Japan
    • Boston University
      Boston, Massachusetts, United States
    • Harbor-UCLA Medical Center
      Torrance, California, United States
  • 2002
    • University of Milan
      Milano, Lombardy, Italy
  • 2000
    • University of Hamburg
      Hamburg, Hamburg, Germany
    • The Catholic University of America
      Washington, Washington, D.C., United States
  • 1998
    • McGill University
      • Department of Surgery
      Montréal, Quebec, Canada
  • 1996–1997
    • Alpert Medical School - Brown University
      • Department of Surgery
      Providence, RI, United States