J Groen

Erasmus MC, Rotterdam, South Holland, Netherlands

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Publications (144)756.58 Total impact

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    ABSTRACT: Most patients with neuro-urological disorders require life-long medical care. The European Association of Urology (EAU) regularly updates guidelines for the diagnosis and treatment of these patients. To provide a summary of the 2015 updated EAU Guidelines on Neuro-Urology. Structured literature searches in several databases were carried out to update the 2014 guidelines. Levels of evidence and grades of recommendation were assigned where possible. Neurological disorders often cause urinary tract, sexual, and bowel dysfunction. Most neuro-urological patients need life-long care for optimal life expectancy and quality of life. Timely diagnosis and treatment are essential to prevent upper and lower urinary tract deterioration. Clinical assessment should be comprehensive and usually includes a urodynamic investigation. The neuro-urological management must be tailored to the needs of the individual patient and may require a multidisciplinary approach. Sexuality and fertility issues should not be ignored. Numerous conservative and noninvasive possibilities of management are available and should be considered before a surgical approach is chosen. Neuro-urological patients require life-long follow-up and particular attention has to be paid to this aspect of management. The current EAU Guidelines on Neuro-Urology provide an up-to-date overview of the available evidence for adequate diagnosis, treatment, and follow-up of neuro-urological patients. Patients with a neurological disorder often suffer from urinary tract, sexual, and bowel dysfunction and life-long care is usually necessary. The update of the EAU Guidelines on Neuro-Urology, summarized in this paper, enables caregivers to provide optimal support to neuro-urological patients. Conservative, noninvasive, or minimally invasive approaches are often possible. Copyright © 2015 European Association of Urology. Published by Elsevier B.V. All rights reserved.
    European Urology 08/2015; DOI:10.1016/j.eururo.2015.07.071 · 13.94 Impact Factor
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    ABSTRACT: To validate a noninvasively estimated measure of urinary bladder contractility by correlating it with 3 existing invasive contractility parameters and to compare and correlate those invasive parameters. A group of 74 patients, recruited in 3 different hospitals, and eligible for transurethral resection of the prostate on clinical grounds, were noninvasively studied preoperatively using the condom catheter method. The maximum condom pressure pcond.max measured during a mechanical interruption of flow rate was considered an estimate of urinary bladder contractility and compared to conventional contractility parameters calculated from preoperative (invasive) pressure-flow studies. The highest correlations were found between the invasive parameters. The correlation between the noninvasive parameter on the one hand and the invasive parameters on the other hand was lower, but mostly significant. In a number of patients, pcond.max underestimated the isovolumetric bladder pressure. The underestimated patients were more obstructed than those who were not underestimated and had a higher (invasively measured) contractility. When the underestimated patients were deselected, the correlation between the noninvasive pcond.max and the invasive parameters in the remaining 52 patients was higher. The 4 tested contractility parameters represent different aspects of urinary bladder contractility. Nevertheless, there was a significant correlation among them supporting the concept of a common basis, that is, detrusor contractility. The invasive contractility parameter bladder contractility index overestimated contractility in patients with lower urinary tract symptoms and/or benign prostatic enlargement. A modified parameter is suggested. Copyright © 2015 Elsevier Inc. All rights reserved.
    Urology 07/2015; 86(1). DOI:10.1016/j.urology.2015.03.031 · 2.19 Impact Factor
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    ABSTRACT: Tibial nerve stimulation (TNS) is a promising therapy for non-neurogenic lower urinary tract dysfunction and might also be a valuable option for patients with an underlying neurological disorder. We systematically reviewed all available evidence on the efficacy and safety of TNS for treating neurogenic lower urinary tract dysfunction (NLUTD). The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement. After screening 1943 articles, 16 studies (4 randomized controlled trials [RCTs], 9 prospective cohort studies, 2 retrospective case series, and 1 case report) enrolling 469 patients (283 women and 186 men) were included. Five studies reported on acute TNS and 11 on chronic TNS. In acute and chronic TNS, the mean increase of maximum cystometric capacity ranged from 56 to 132mL and from 49 to 150mL, and the mean increase of bladder volume at first detrusor overactivity ranged from 44 to 92mL and from 93 to 121mL, respectively. In acute and chronic TNS, the mean decrease of maximum detrusor pressure during the storage phase ranged from 5 to 15cm H2O and from 4 to 21cm H2O, respectively. In chronic TNS, the mean decrease in number of voids per 24h, in number of leakages per 24h, and in postvoid residual ranged from 3 to 7, from 1 to 4, and from 15 to 55mL, respectively. No TNS-related adverse events have been reported. Risk of bias and confounding was high in most studies. Although preliminary data of RCTs and non-RCTs suggest TNS might be effective and safe for treating NLUTD, the evidence base is poor, derived from small, mostly noncomparative studies with a high risk of bias and confounding. More reliable data from well-designed RCTs are needed to reach definitive conclusions. Early data suggest tibial nerve stimulation might be effective and safe for treating neurogenic lower urinary tract dysfunction, but more reliable evidence is required. Copyright © 2015 European Association of Urology. Published by Elsevier B.V. All rights reserved.
    European Urology 07/2015; 68(5). DOI:10.1016/j.eururo.2015.07.001 · 13.94 Impact Factor
  • J. Groen · B.F.M. Blok ·
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    ABSTRACT: Sacral neuromodulation may treat some urinary bladder filling and emptying problems effectively. After a brief summary of the physiology of the micturition cycle, this chapter describes the problems to which neuromodulation may be applied, how the system is composed and how it might work. An overview of reported outcomes in patients is given. Finally, expectations are expressed about future developments.
  • Elaine Utomo · Jan Groen · Bertil Fm Blok ·
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    ABSTRACT: The most common type of functional bladder outlet obstruction in patients with neurogenic bladder is detrusor-sphincter dyssynergia (DSD). The lack of co-ordination between the bladder and the external urethral sphincter muscle (EUS) in DSD can result in poor bladder emptying and high bladder pressures, which may eventually lead to progressive renal damage.
    Cochrane database of systematic reviews (Online) 05/2014; 5(5):CD004927. DOI:10.1002/14651858.CD004927.pub4 · 6.03 Impact Factor
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    ABSTRACT: Aims: The aim of this study was to determine the accuracy of the non-invasive condom catheter method for diagnosing B(ladder) O(utlet) O(bstruction) in patients eligible for T(rans)U(rethral) R(esection) of the P(rostate). Methods: A group of 71 patients eligible for TURP on clinical grounds were invasively and non-invasively studied. On the basis of invasive pressure-flow studies they were stratified into obstructed, equivocal or unobstructed, according to the International Continence Society standard. Subsequently they were diagnosed non-invasively on the basis of a free flowrate measurement, or on the basis of the free flowrate measurement plus the isovolumetric bladder pressure measured with the condom catheter method. R(eceiver) O(perating) C(haracteristic)s were calculated. Results: The A(rea) U(nder) the (RO)C for discriminating unobstructed/equivocal patients from obstructed patients was 0.68 in our population. This improved to 0.84 for the 50 patients in whom the isovolumetric bladder pressure was not underestimated by the non-invasive method. Conclusions: In our population of TURP patients, the low flowrates affected the accuracy of the condom method to a degree that it did not perform better than a free flowrate measurement, which performed remarkably well. By excluding measurements in which the condom pressure underestimated the isovolumetric bladder pressure this method may contribute to a more accurate, patient friendly diagnosis of BOO in these patients. In the present study this exclusion was done by comparison with an invasive pressure measurement. A practical non-invasive test would necessitate a non-invasive exclusion criterion, which might be based on the risetime of the condom pressure.
    Neurourology and Urodynamics 04/2014; 33(4). DOI:10.1002/nau.22427 · 2.87 Impact Factor
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  • K. Zaccai · J. Groen · M. Wildhagen · G.R. Dohle ·
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    ABSTRACT: IntroductieSuspensieoperaties voor stressincontinentie (SUI) zijn niet altijd succesvol: ongeveer 20% van de patienten heeft na TVT/TVTO persisterend urineverlies. De preoperatief gemeten valsalva leak point pressure (VLPP) lijkt in meerdere studies geassocieerd te zijn met postoperatief urineverlies. Een recente systematische review laat echter geen significant verband zien. Wij onderzochten de associatie tussen een lage VLPP en de kans op persisterend urineverlies.Materiaal en methodenIn deze retrospectieve studie werden 123 vrouwen met stressincontinentie die in de periode 2000 t/m 2012 een TVT/TVTO-operatie ondergingen geëvalueerd. De ernst van de incontinentie werd gegradeerd volgens Stamey. Een lage VLPP werd gedefinieerd als lekkage bij ≤ 60 cmH2O blaasdrukstijging bij een volume van 200 ml. Succes van de operatie werd omschreven als postoperatief geen urineverlies of verminderd urineverlies doch patiënttevredenheid. Baselinekarakteristieken en complicaties werden geregistreerd.
    11/2013; 3(7):184-185. DOI:10.1007/s13629-013-0107-8
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    ABSTRACT: Objective: To evaluate the urodynamic changes in patients treated with Adjustable Continence Therapy for men (ProACT) for postprostatectomy incontinence and to explore the clinical and urodynamic preimplantation parameters as predictors of clinical outcome. Materials and methods: Patients underwent urodynamic studies before and after ProACT implantation. ProACT was considered successful if patients used none or 1 dry precautionary pad and nonsuccessful if the patient reported ≥1 wet pad/d. The pre- and postimplantation assessments were retrospectively compared within and between the success and nonsuccess groups. Multivariate logistic regression analysis was performed to investigate the association between the preimplantation variables and the clinical outcomes of ProACT implantation. Results: A total of 49 patients were included, 37 with successful and 12 with nonsuccessful clinical outcome. Postimplantation urodynamic studies were performed a median of 9 months after ProACT implantation. In the successfully treated patients, maximum free flow rate, bladder contractility index, maximum of bladder contractility parameter W, and bladder voiding efficiency were significantly lower after implantation. The detrusor pressure at maximum flow rate, postvoid residual urine volume, and bladder outlet obstruction index were significantly higher. A longer duration of urinary incontinence, the use of >5 pads daily, and a smaller cystometric bladder capacity were all independently associated with nonsuccessful clinical outcome after ProACT implantation. Conclusion: ProACT implantation with successful clinical outcome resulted in greater urethral resistance during voiding and reduced bladder contraction strength. A longer duration of incontinence, the use of >5 pads daily, and a smaller cystometric bladder capacity were independent predictors of unsuccessful clinical outcomes, suggesting ProACT implantation should be considered sooner, rather than later, after conservative treatment of postprostatectomy incontinence has failed.
    Urology 02/2013; 81(6). DOI:10.1016/j.urology.2013.01.020 · 2.19 Impact Factor
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    ABSTRACT: We analyzed the impact of radical retropubic prostatectomy (RRP) on the urethral sphincter function as assessed by urethral pressure profilometry (UPP) and its relation to post-radical prostatectomy continence status. Furthermore, we analyzed the effect of intensive pelvic floor muscle exercises (PFME) on the urethral sphincter function. Sixty-six patients were included in the study. UPP was performed before RRP and 26 weeks after catheter removal. All patients were instructed in PFME, however, the intensity of PFME varied between instructions based on an information folder only (F-PFME) and intensive guidance by a physiotherapist, in addition to the folder (PG-PFME). In 66 patients, pre- as well as postoperative UPP was evaluable. After surgery, the functional profile length and the maximum urethral closure pressure (MUCP) showed a median decrease of 64% and 41%, respectively. For men who had regained continence after 6 months the median MUCP was significantly higher both before and after operation as compared to men who were still incontinent. In multivariate analysis, non-nerve sparing approach was a prognostic factors for a higher relative decrease of the MUCP after RRP. Comparing the PG-PFME group with the F-PFME group there were no significant differences in changes in UPP parameters. A poor preoperative MUCP seems to be an important prognostic factor for persistent incontinence after RRP. Non-nerve sparing approach seems to be an important prognostic factor for impairment of the urethral sphincter function as measured by UPP. More intensive physiotherapy seems to have no additional effect on the postoperative urethral sphincter function as measured by UPP.
    Neurourology and Urodynamics 06/2012; 31(5):646-51. DOI:10.1002/nau.21243 · 2.87 Impact Factor
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    ABSTRACT: We aim to quantify changes in detrusor function and pressure-flow parameters after radical retropubic prostatectomy (RRP) and to determine the impact of the level of intensity of pelvic floor muscle exercises (PFME) on these changes. We also tried to identify preoperative urodynamic factors, predictive of postoperative continence status. Sixty-six patients were included in the study. An urodynamic examination was performed before surgery and 26 weeks after catheter removal. All patients were instructed in PFME. However the intensity of PFME varied between instructions based on an information folder only (F-PFME) and intensive guidance by a physiotherapist, in addition to the folder (PG-PFME). In 66 men pre- as well as postoperative urodynamic studies were available for analysis. Overall, Q(max) increased, p(det.Qmax) and the urethral resistance factor URA decreased significantly after surgery. At baseline, detrusor overactivity (DOA) was found in 34% and 5.3% of the men who were still incontinent 6 months postoperatively and those who regained continence, respectively (P = 0.015). Postoperatively, Q(max) was significantly higher (P = 0.04) and URA significantly lower (P = 0.047) in the physiotherapist-guided group. No prognostic standard urodynamic factors for post-RP incontinence (PRPI) were identified. In univariate analysis, preoperative DOA is associated with a higher risk of remaining incontinent after surgery. However, in multivariate analysis, urodynamic parameters predictive of PRPI could not be identified. Therefore, standard preoperative filling cystometry and pressure-flow studies seem to have no role as preoperative predictors of PRPI in patients with localized prostate cancer. More intensive PFME might have a lowering effect on bladder outflow resistance after RRP.
    Neurourology and Urodynamics 06/2012; 31(5):637-41. DOI:10.1002/nau.21199 · 2.87 Impact Factor

  • European Urology Supplements 02/2012; 11(1):e290-e290a. DOI:10.1016/S1569-9056(12)60287-5 · 3.37 Impact Factor
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    01/2012; 26(1):10. DOI:10.4081/uij.2012.e10
  • Jan Groen · Bertil F.M. Blok · J.L.H. Ruud Bosch ·
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    ABSTRACT: We evaluated the results of sacral neuromodulation after 5-year followup in women with refractory idiopathic urge urinary incontinence. A neuromodulation system with an original (nontined) lead was implanted by open surgery after a positive percutaneous nerve evaluation in 60 women from 1990 to 2004. Voiding incontinence diary parameters were used to evaluate efficacy. Success was defined as at least a 50% decrease in the number of incontinence episodes or pads used daily. Safety was also evaluated. The success rate gradually decreased from 52 patients (87%) at 1 month to 37 (62%) at 5 years. Complete continence persisted in 15% of patients. The system was still used by 80% of patients at 5 years. In 32 patients a total of 57 adverse events occurred, which were not severe (Clavien grade I and IIIb in 61% and 39%, respectively). Sacral neuromodulation appears to be a safe technique for refractory idiopathic urge urinary incontinence in women. The success rate gradually decreased to 62% after 5 years with 15% of patients completely continent.
    The Journal of urology 09/2011; 186(3):954-9. DOI:10.1016/j.juro.2011.04.059 · 4.47 Impact Factor

  • 05/2011; 1(3). DOI:10.1007/s13629-011-0044-3
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    ABSTRACT: To investigate the proportion of viral respiratory tract infections among acute undifferentiated fevers (AUFs) at primary health facilities in southern Vietnam during 2001-2005, patients with AUF not caused by malaria were enrolled at twelve primary health facilities and a clinic for malaria control program. Serum was collected on first presentation (t0) and after 3 weeks (t3) for serology. After exclusion of acute dengue infection, acute and convalescent serum samples from 606 patients were using enzyme-linked immunoassays to detect IgA, as well as IgM and IgG antibodies against common respiratory viruses. Paired sera showed the following infections: human parainfluenza virus (HPIV, 4.7%), influenza B virus (FLUBV, 2.2%), influenza A virus (FLUAV, 1.9%) and human respiratory syncytial virus (HRSV, 0.6%). There was no association between type of infection and age, sex or seasonality; some inter-annual differences were observed for influenza. Antibody prevalence, indicative of previous infections, was relatively low: HPV, 56.8%, FLUBV, 12.1%; FLUAV, 5.9% and HRSV, 6.8%.
    The Southeast Asian journal of tropical medicine and public health 09/2010; 41(5):1116-26. · 0.72 Impact Factor
  • B. F. M. Blok · J. Groen ·

    European Urology Supplements 04/2010; 9(2):105-105. DOI:10.1016/S1569-9056(10)60243-6 · 3.37 Impact Factor
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    ABSTRACT: To compare the effect on the recovery of incontinence after retropubic radical prostatectomy (RRP) of intensive physiotherapist-guided pelvic floor muscle exercises (PG-PFME) in addition to an information folder, with PFME explained to patients by an information folder only (F-PFME), and to determine independent predictors of failure to regain continence after RRP. We postulated that a 10% increase in the proportion of men who regained continence at 6 months with PG-PFME compared with men treated with F-PFME only would constitute a clinically relevant effect. To show statistical significance of this difference with a power of 80%, 96 men should be randomized to each of the two arms. One day before operation, all patients received verbal instruction and an information folder on PFME. Patients randomized to the F-PFME arm received no further physiotherapist guidance, whereas those in the PG-PFME arm received a maximum of nine sessions with the physiotherapist. The men underwent a 1-h pad-test at 1, 12 and 26 weeks, and a 24-h pad-test at 1, 4, 8, 12 and 26 weeks after catheter removal. We defined 'continence' as urine loss of <1 g at the 1-h and <4 g at the 24-h pad-test. During the 2-year recruitment period, the number of patients randomized fell short of the target determined by the sample size calculation, because of limitations of resources and unexpected changes in treatment preferences. Despite this, we analysed the data. Of the 82 randomized patients, 70 completed the study. Of these, 34 and 36 men had been assigned to the PG-PFME and the F-PFME group, respectively. At 6 months after RRP, 10 (30%) and nine (27%) men were completely dry on both the 1-h and 24-h pad-test in the PG-PFME and the F-PFME group, respectively (difference not significant). In a multivariate analysis the amount of urine loss at 1 week after catheter removal seemed to be an independent prognostic factor for failure to regain continence. PG-PFME seems to have no beneficial effect on the recovery of continence within the first 6 months after RRP, over an instruction folder-guided approach. However, due to under-powering there is a high risk of type II error. Nevertheless, these findings add to the knowledge base for availability in meta-analyses and can serve as a starting point for the design of new randomized studies.
    BJU International 03/2010; 106(4):515-22. DOI:10.1111/j.1464-410X.2010.09159.x · 3.53 Impact Factor
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    ABSTRACT: To investigate which recent infection could have caused the present dengue-like symptoms, in adult patients clinically fulfilling the WHO criteria for dengue, in which serologically were not confirmed for dengue virus infections. Prospective study. During an outbreak of dengue (between May 1995 and May 1996) 118 consecutive adults (>13 years) suspected by the WHO 1997 case definition of DF or DHF were investigated. Patients were examined for history of illness, physical and laboratory findings consisting of full blood counts, prothrombin time (PT), activated partial thromboplastin time (aPTT), liver function (bilirubin, ASAT, ALAT), renal function (creatinine), and serological assays included dengue, hantavirus, chikungunya, R. typhi, R. tsutsugamuchi, rubella virus, influenza A virus, and leptospira. In 58 of the total 118 patients, recent dengue virus infection was serologically confirmed. In 20 of the remaining 60 patients, we found serological evidence of another recent infection: hantavirus (5), chikungunya virus (2), R. typhi (5), R. tsutsugamuchi (2), rubella virus (3), influenza A virus (1), and leptospira (2). No evidence for recent infection with any of the mentioned agents was detected in the remaining 40 specimens. We conclude that based on clinical characteristics alone, it is not easy to diagnose dengue. Specific laboratory tests to differentiate dengue from other febrile illnesses are needed. Among these, in Indonesia hantavirus infection should be considered as well.
    Acta medica Indonesiana 05/2009; 41(2):75-80.
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    ABSTRACT: Diagnosing dengue in febrile patients is challenging. Of a total of 459 patients with acute undifferentiated fever, randomly selected from 12 primary health facilities and 1 clinic of the provincial malaria station in southern Vietnam, dengue-specific antibody (Ab) and NS1Ag enzyme-linked immunosorbent assay (ELISA) (Platelia, Bio-Rad Laboratories, Hercules, CA 94547, US) were performed on acute (t0) and convalescent (t3 weeks) sera. Polymerase chain reaction (PCR) was used for confirmation. Based on a composite of the NS1Ag-ELISA, Ab-ELISA, and PCR results, 54 (12%) patients had acute dengue. Positive and negative predictive values were 65% and 98% for the Ab-based diagnosis and 91% and 92% for NS1Ag, respectively. The agreement between Ab- and NS1Ag-based diagnosis was poor (kappa value, 0.2). Two patients without dengue had detectable NS1Ag on t0 and t3, 1 just above the cutoff value and 1 with very high values. For 5 dengue patients, NS1Ag was still detectable at very high levels at t3. Dengue NS1Ag can be used for early diagnosis of dengue; infrequent false-positive results need further clarification.
    Diagnostic microbiology and infectious disease 03/2009; 63(4):372-8. DOI:10.1016/j.diagmicrobio.2008.12.009 · 2.46 Impact Factor

Publication Stats

5k Citations
756.58 Total Impact Points


  • 1999-2015
    • Erasmus MC
      • • Department of Urology
      • • Department of Virology
      Rotterdam, South Holland, Netherlands
  • 2011
    • University Medical Center Utrecht
      • Urology
      Utrecht, Utrecht, Netherlands
  • 2007
    • McGill University
      • Division of Urology
      Montréal, Quebec, Canada
  • 1994-2002
    • Erasmus Universiteit Rotterdam
      • • Department of Urology
      • • Department of Virology
      Rotterdam, South Holland, Netherlands
  • 1995
    • Queen Astrid Military Hospital
      Bruxelles, Brussels Capital Region, Belgium
  • 1991
    • Medisch Spectrum Twente
      • Hospital Medical Spectrum Twente
      Enschede, Overijssel, Netherlands
  • 1990
    • National Veterinary Institute, Sweden
      Uppsala, Uppsala, Sweden
  • 1989
    • National Institute for Public Health and the Environment (RIVM)
      Utrecht, Utrecht, Netherlands