Blaise Meyrat
University Hospital of Lausanne
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Featured researches published by Blaise Meyrat.
Journal of Pediatric Urology | 2007
Christophe Gapany; Nicolas Grasset; Stéphane Tercier; Pascal Ramseyer; Peter Frey; Blaise Meyrat
OBJECTIVE To determine whether specific steps taken after a critical quality control of our results in hypospadias surgery lead to a decrease in fistula rate. PATIENTS AND METHODS Retrospective review of prospectively collected data. Between 1994 and 2001, our series of 85 tubularized plate urethroplasties (modified Duplay or Duplay-Snodgrass procedure) had a fistula rate of 25.9%. In 2001, we modified our approach by systematically padding the urethral suture with a layer of vascularized subcutaneous preputial tissue, as described by Snodgrass. Scrotal hypospadias were excluded. Surgical outcome was assessed at 1 and 12 months. In both groups, all repairs were performed by or under direct supervision of the senior author (BJM). RESULTS After 2001, 57 hypospadias repairs were performed in 57 patients aged 8 months to 14 years (median 1.4 years). Fistula occurred in two cases, one of which closed spontaneously within 6 months. Our fistula rate had dropped to 3.5%, with a minimum follow up of 12 months. CONCLUSION Covering the urethral suture with a padding flap of vascularized preputial tissue helps avoid fistula formation. Technique modification after critical appraisal of our own series led to a much better outcome in this demanding surgery.
Nephrology Dialysis Transplantation | 2013
Francois Cachat; Christophe Combescure; Hassib Chehade; Dolores Mosig; Blaise Meyrat; Peter Frey; Eric Girardin
BACKGROUND Microalbuminuria (MA) has been shown to be an early biomarker of renal damage. It is postulated that MA is the early result of hyperfiltration, which could evolve into glomerular sclerosis and renal failure if hyperfiltration is left untreated. We hypothesized that MA is a good indicator of hyperfiltration in children with kidney disorders, obviating the need to calculate the filtration fraction (FF). METHODS A total of 155 children or young adults were prospectively included [42 single kidney (SK), 61 vesico-ureteral reflux, 23 obstructive uropathies, 29 other kidney diseases]. We measured inulin, para-aminohippuric acid clearances, FF and MA. Prediction of hyperfiltration was explored by studying the association between the FF and other variables such as urinary albumin (Alb), urinary albumin-creatinine ratio (ACR) and creatinine clearance. RESULTS A significant but weak association between urinary Alb or ACR and FF was found in subjects with an SK (Spearman correlation coefficients 0.32 and 0.19, respectively). Multivariate analysis also showed that urinary Alb and ACR significantly predict FF only in subjects with an SK (r(2) = 0.17, P = 0.01 and r(2) = 0.13, P = 0.02, respectively). This holds true only in subjects with an SK and inulin clearance >90 mL/min/1.73 m(2) (r(2) = 0.41, P < 0.001). There was no association between creatinine clearance and FF. CONCLUSIONS MA is not associated with FF in our subjects with nephro-urological disorders, except in those with an SK, where the association is weak, indicating that MA is due to other mechanisms than high FF and cannot predict hyperfiltration in such groups.
The Journal of Urology | 2011
Gezim Dushi; Peter Frey; Pascal Ramseyer; Olivier Vernet; Blaise Meyrat
PURPOSE We assessed the correlation between urodynamic score and presence of symptoms in children with lipomyelomeningocele, and the usefulness of this measure in monitoring these children. MATERIALS AND METHODS We prospectively evaluated 29 patients 1 month to 13 years old (mean 1.9 years) with lipomyelomeningocele from 1995 to 2010. A 4-parameter urodynamic score ranging from 0 to 17 was assigned to each patient at diagnosis and followup. Indications for surgery were presence of symptoms and signs or abnormal urodynamic score. Children were divided into 2 groups, symptomatic and asymptomatic. The latter group was further divided into operated and conservatively managed cases. Average followup was 6.7 years (range 2 to 16). RESULTS The symptomatic group contained 11 children (38%) operated on at a mean age of 2.9 years. Mean followup was 6.7 years (range 2 to 12). All patients presented with an abnormal urodynamic score. Postoperative urodynamic score improved in 6 patients (55%), remained abnormal in 4 (36%) and deteriorated in 1 (9%). The asymptomatic group contained 18 patients, of whom 7 (39%) were operated on at a mean age of 1.4 years. Mean followup was 10 years (range 3 to 16). Postoperative score improved in 6 patients (86%) and remained unchanged in 1 (14%). A total of 11 cases (61%) were managed conservatively, with a mean followup 4.3 years (range 2 to 7). Of these patients 3 (27%) presented with late urodynamic score deterioration at 3, 5 and 6 years of followup while remaining asymptomatic. CONCLUSIONS Urodynamic score is a useful tool in monitoring children with lipomyelomeningocele because it has a good correlation with the presence of symptoms.
Urology | 2003
Ariane Boubaker; Blaise Meyrat; Peter Frey; Angelika Bischof Delaloye
OBJECTIVES To evaluate the renal function outcome in children with unilateral hydronephrosis and urinary flow impairment at the pelviureteral junction with respect to the therapeutic strategy. METHODS We retrospectively selected 45 children with iodine-123-hippuran renography performed at diagnosis and after 3 or more years of follow-up. All children had bilateral nonobstructive pattern findings on diuretic renography at follow-up. Eleven children were treated conservatively, and 34 underwent unilateral pyeloplasty. Split and individual renal function, measured by an accumulation index, was computed from background-corrected renograms for the affected and contralateral kidneys at diagnosis and the follow-up examination. RESULTS Of 11 children treated conservatively, 9 had normal bilateral function at diagnosis, all had reached normal function at follow-up. Of the 34 operated kidneys, 12 (38%) had initially normal function that remained normal at the follow-up examination, and 22 had impaired function that had normalized at the follow-up examination in 15 (68%). The function of the contralateral kidneys was increased in 5 of 8 children with persistently abnormal affected kidneys. Pyeloplasty was performed in 23 children (68%) and 11 children (32%) younger and older than 1 year, respectively. The function of the affected kidneys increased in both groups, but normalization occurred only in the younger children. CONCLUSIONS Of the children selected for conservative treatment, 82% had normal bilateral renal function at diagnosis that was normal in all at the follow-up examination. Of the children treated surgically, 65% had initially impaired function of the affected kidney that improved in 87% after pyeloplasty. Normalization of function was observed only in children who were younger than 1 year old at surgery. Persistently low function of the affected kidney was compensated for by the contralateral one regardless of the age at surgery.
The Journal of Urology | 2012
E. Stathopoulos; V. Muehlethaler; M. Rais; L. Alamo; G. Dushi; P. Frey; P. Ramseyer; Blaise Meyrat
PURPOSE We preoperatively assessed neurovesical function and spinal cord function in children with anorectal malformations. In cases of neurovesical dysfunction we looked for an association with vertebral malformation or myelodysplasia. MATERIALS AND METHODS We prospectively evaluated 80 children with anorectal malformations via preoperative urodynamics and magnetic resonance imaging of the spine. Bladder compliance and volume, detrusor activity and vesicosphincteric synergy during voiding allowed urodynamic evaluation. Results were reported according to Wingspread and Krickenbeck classifications of anorectal malformations. RESULTS Urodynamic findings were pathological in 14 children (18%). Pathological evaluations did not seem related to type of fistula or level of anorectal malformation. Vertebral anomalies were seen in 34 patients (43%) and myelodysplasia in 16 (20%). Neither vertebral anomaly nor myelodysplasia seemed associated with type of fistula or severity of anorectal malformation. Of 14 children with pathological urodynamics no vertebral anomaly or myelodysplasia was found in 7. Of 66 children with normal urodynamics 40 presented with vertebral or spinal malformation. CONCLUSIONS Lower urinary tract dysfunction is common in patients with anorectal malformations. Normal spine or spinal cord does not exclude neurovesical dysfunction. Myelodysplasia or vertebral anomaly does not determine lower urinary tract dysfunction. Thus, we recommend preoperative urodynamic assessment of the bladder and magnetic resonance imaging of the spine in children with anorectal malformations.
Journal of Pediatric Urology | 2017
Romaine de Sépibus; F Cachat; Blaise Meyrat; Gezim Dushi; Ariane Boubaker; Mohamed Faouzi; Eric Girardin; H Chehade
BACKGROUND Albuminuria is a potential biomarker of chronic kidney disease (CKD) in various glomerular diseases. Vesicoureteral reflux (VUR) often progresses to CKD, and study is required of use of albuminuria as a biomarker for this condition. The aim of this study was to evaluate the association between albuminuria and glomerular filtration rate (GFR) or filtration fraction (FF) in children with VUR. STUDY DESIGN In this retrospective study, renal parameters of 141 children with VUR were investigated, using inulin clearance, FF, and albuminuria. The association between urinary albumin to creatinine ratio (ACR), GFR, and FF was analyzed in a continuous manner by calculating the β coefficient, and also in a binary manner by calculating the OR. RESULTS Using both continuous and binary analyses, ACR values were negatively and significantly associated to GFR values in patients with low, normal, or high FF values (Table). It was also positively and significantly associated with FF values in patients with low, normal or high GFR values (Table). No association was found between ACR and gender, VUR stages or laterality, number of urinary tract infection, presence of a single functional kidney, history of reflux surgery, or renal scars or hypertension. DISCUSSION ACR is associated with CKD in patients with VUR. In addition, increased urinary albumin excretion cannot be completely and solely explained by decreased GFR and/or increased FF values. The two main limitations of this study are the crude assessment of renal scarring, which prevented finer analysis between albuminuria and renal scarring surface area, and that the study cohort may not be representative of the true VUR population. CONCLUSION This study shows that albuminuria is associated with decreased renal function in patients with VUR and that it could be used to monitor renal function in this condition.
The Journal of Nuclear Medicine | 2001
Ariane Boubaker; John O. Prior; Cristian Antonescu; Blaise Meyrat; Peter Frey; Angelika Bischof Delaloye
The Journal of Urology | 2003
Ariane Boubaker; John O. Prior; Blaise Meyrat; Angelika Bischof Delaloye
Swiss Medical Weekly | 2007
Christophe Oberson; Ariane Boubaker; Pascal Ramseyer; Blaise Meyrat; Peter Frey
Journal of pediatric surgery case reports | 2016
Alexis Litchinko; Blaise Meyrat; Antoine Nobile; Lara Raffoul; Gezim Dushi; Vanina Estremadoyro