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Introduction Non-neurogenic detrusor overactivity in children leads to varying degrees of functional impairments (urinary urgency, pollakiuria, urge incontinence, nocturia). Botulinum toxin has shown its effectiveness in the management of detrusor overactivity in neurological patients. Objectives To evaluate the relevance of intravesical Botulinum toxin injections for the treatment of non-neurogenic overactive bladders in children. These pediatric patients were resistant to all the usual therapeutics (e.g. bladder/bowel rehabilitation, anticholinergic drugs, management of diet/hygiene habits and constipation, percutaneous posterior tibial nerve stimulation). Materials and methods 8 children (mean age: 12.5years), 5 girls, 3 boys with daytime and/or nighttime incontinence and non-neurogenic detrusor overactivity validated by urodynamic testing. Urodynamic testing was conducted before the injections as well as 6weeks and 1year post injections. We used Dysport® 8 Speywood Units/kg injected via cystoscopy into 25 different sites. Results We noted improvements without any complaints during bladder voiding for all patients, in 6 patients the overactivity disappeared after 1 injection. Compliance was improved early-on in half the cases and at 1year for all cases (from 12% to 61%, p=0.01). Noninhibited contractions decreased constantly in both frequency and intensity. Clinical symptoms improved: mean of 7.75 daytime urinary incontinence episodes (IE) per week before the injection vs. 3 after the procedure (p=0.04). For nighttime IE the improvement was even more noticeable with 7.38 nighttime IE episodes per week before the injection vs. 2.06 after the procedure (p=0,02). Conclusion Intradetrusor Botulinum toxin injections are a potential therapeutic option for the management of non-neurogenic detrusor overactivity in children resistant to the usual treatments.

We present the results of a new technique using a pedicled cutaneous flap for continent cystostomy.A total of 15 boys and 8 girls (mean +/- SD age 13.4 +/- 6.4 years) underwent continent cystostomy for neurogenic bladder (20), bladder exstrophy (2) and sequelae of hypospadias (1) between 1999 and 2008. In this procedure a rectangular pedicled flap is surgically elevated from a hairless area on the abdomen. The flap is tubularized and passed through the anterior abdominal wall directly into the bladder. A submucosal detrusor incision is made to expose the bladder mucosa, and the distal part of the flap is anastomosed to the bladder mucosa in a circular manner. The tube is positioned along the incised detrusor, which is closed over. Viability of the flap, self-catheterization management and continence status are then evaluated.Mean +/- SD followup was 4.5 +/- 3.1 years. There was 1 case of distal necrosis of the flap, which required a secondary surgery using the Mitrofanoff technique. The 22 remaining flaps were initially viable, although 2 patients were eventually lost to followup and 3 subsequently presented with false-passage incidents requiring a few days of calibration using a balloon catheter. Dryness was achieved immediately in 73% of the cases. After adding a complementary bulking agent the dryness rate reached 77%.We present a novel approach to continent cystostomy that is safe and easy to perform. This technique is a less invasive and more efficient alternative to other commonly used approaches.

This paper is about an optimization method which has been developed to deal with trajectory optimization and mission analysis of an aeroassisted orbital transfer vehicle (OTV), in the context of preliminary design studies. Although this kind of trajectory can already be computed with existing trajectory optimization tools, we need a faster and robust tool which can be integrated as a “black box” in a multidisciplinary design process, in order to study rapidly many different OTV concepts and missions. In this context, our objective is not to get a very precise “optimal trajectory”, as existing “heavy” optimization tools do, but a solution precise enough to give a good insight of the performance (namely, the apogee altitude variation) and the mechanical and thermal loads. Incidentally, the solution obtained may also be used as an initial guess for a more precise trajectory optimization tool. To achieve this goal, we have studied parametric formulations of the control law, with optimization of the switching times. This development has been done considering a low lift-to-drag ratio vehicle (controlled only with the bank angle), like the aerocapture-designed version of the Mars Sample Return Orbiter. The cost function to be minimized is the heat flux, which is a key parameter for the multidisciplinary design of this kind of vehicle. The parametric formulation eventually chosen yields a good level of precision and robustness. Also, the study has been pushed further with the optimization of some mission parameters in the same process, in order to get directly preliminary answers to some trade-off issues in the mission analysis, like the choice of the initial perigee altitude.

Summary Objective To assess the objective efficacy of transcutaneous posterior tibial nerve stimulation in children presenting with overactive bladder resistant to well conducted treatment. Download : Download high-res image (63KB) Download : Download full-size image Material and method This was a randomized, double-blind, controlled study on 20 children with OAB. All patients were previously treated with anticholinergic drugs associated with detrusor rehabilitation, diet advice, bladder-voiding hygiene and constipation treatment, with poor clinical results. Patients were randomized into two groups: -Group A: treatment with PTNS (n = 11). -Group B: sham treatment (n = 9). The program lasted 12 consecutive weeks with two 30-minutes sessions a week. Each patient underwent pre-stimulation urodynamic testing to validate bladder overactivity followed by a post-stimulation testing. Pre- and post-stimulation urodynamic parameters were compared in order to objectively evaluate the treatment’s efficacy. The patients noted their incontinence episodes for 7 consecutive days in a diary before the beginning of the program, in the middle and at the end of it: this led to computing an incontinence score (score ranged from 0 to 13, from good to poor). The difference between the pre-stimulation and post-stimulation score enabled to express clinical results in terms of poor (less than a 3-point decrease), medium (a 3 to 5-point decrease), good (6 to 8-point decrease), very good (final score ranged between 0 and 3). Children were questioned regarding their impression of being stimulated or not. Results In Group A, there were five very good clinical results (45%), one medium (10%) and five poor results (45%). In group B, nine very good results (66%) and three poor results (33%) were noted. Regarding urodynamic testing, volume voided during urgency (184 mL to 265 mL), maximal cystomanometry volume (215 mL to 274 mL) and volume at the onset of the first overactive detrusor contraction (ODC) (48 mL to 174 mL) were significantly increased in Group A (p = 0.002, p = 0.024 and p = 0.001) and maximal bladder pressure during ODC had decreased (61 to 46) (p = 0.042). 85% children in group A thought they were being stimulated vs. 70% in group B. Volume voided during urgency (mL) Maximum pressure during overactive detrusor contraction Volume at the first overactive detrusor contraction (mL) Group A: Initial mean 184 61 48 Treated with PTNS Final mean 265 46 174 Group B: Initial mean 184 56 61 Placebo Final mean 181 67 80 Conclusion Even though we noticed urodynamics improvements in group A, which objectively supports the efficacy of TCTPNS, clinical results remained the same between the two groups. In spite of the small size of our sample, this underlines the placebo effect of any type management in this pediatric population. Studying precisely the maximal useful voltage and duration of stimulation should then be relevant in order to yield maximal benefits from this easy-to-use procedure.

A method to assess vulnerability of a space mission due to the threat of space debris is presented in this paper. It handles different effects of the threat on the space system used to fulfill the mission: effects from which the system can protect itself from, by reacting, and effects the system must endure. The method is presented through the example of vulnerability assessment of an Earth observation mission, performed by a single satellite. Different effects of space debris are considered on the satellite, depending whether they are large enough to be tracked or not. Numerical results are presented and analyzed to illustrate the proposed approach.