PEDIATRIC UROLOGY

Small intestinal submucosa bladder neck slings for incontinence associated with neuropathic bladder
Misseri R, Cain MP, Casale AJ, Kaefer M, Meldrum KK, Rink RC
Department of Pediatric Urology, James Whitcomb Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana, USA
J Urol. 2005; 174 (4 Pt 2): 1680-2; discussion 1682

• Purpose: We assess the results using small intestinal submucosa (SIS) for neuropathic urinary incontinence in a large single institutional experience. Ambulatory status was considered as a possible predictor of success.
• Materials and Methods: We retrospectively reviewed the charts of patients treated with SIS bladder neck sling procedures for neuropathic urinary incontinence with a leak point pressure less than 25 cm H2O and a minimum of 6 months followup. Continence was defined as wet (requiring pads or diapers) or dry (requiring no pads and dry underwear). Patients were classified as ambulatory (able to ambulate without assistance or using braces, crawling at home) or nonambulatory (confined to a wheelchair). Results were analyzed with regard to patient sex, ambulatory status and simultaneous bladder neck repair.
• Results: A total of 21 females and 15 males 3 to 10 years old (mean age 9 years) were treated with SIS bladder neck slings (sling alone 27, bladder neck repair with SIS sling 9). Slings were performed along with reconstructive surgery in all cases (all had creation of urinary catheterizable channels and simultaneous or prior bladder augmentations). Minimum followup was 6 months (mean 15, range 6 to 42). Overall, 27 of the 36 patients (75%) are dry following bladder neck sling. In patients treated with the sling procedure alone 6 of 8 (75%) nonambulatory females and 8 of 10 (80%) ambulatory females were continent, and 3 of 4 (75%) nonambulatory males and 2 of 5 (40%) ambulatory males were dry.
• Conclusions: SIS has equivalent rates of continence compared to series using rectus fascia in patients with neuropathic urinary incontinence. The ambulatory status of males should be considered when determining which treatment option is best for the patient with myelodysplasia and neuropathic sphincteric incontinence, as in our series ambulatory males undergoing sling placement alone had a poor outcome.
  
  
• Editorial Comment
  The authors report a series of 36 children with neurogenic bladder who underwent a bladder neck sling using small intestinal submucosal (SIS) as manufactured by Cook Urological. SIS has the advantage of being “off-the-shelf.” In addition, in this neurogenic population, rectus muscle and fascia may not be normal and may be further weakened and scarred by harvesting it, making autologous rectus fascia a less favorable alternative. Overall, 75% of the authors’ patients were dry afterwards.
  In general, these results are good, but several important points need to be considered. For the reader, it is important to determine whether this success rate is due to the operative technique or the material being used. In reviewing the data, we do not know whether this is a consecutive series or whether these patients were selected for the SIS sling (and how they may have been selected). We do not know how many other types of slings were performed in the same or similar time period and we have no idea what the authors’ success rates were with other materials or other techniques. Moreover, the 36 patients had widely varying characteristics, including gender, ambulatory status, history of/need for augmentation, and even the type of sling (with or without bladder neck surgery). The authors attempt some sub-group analyses and conclude that the operation works less well in ambulatory males. Though this may be true, it is difficult for the reader to determine this with any certainty in the large, varied group. Also, as in all studies of continence, how the continence is determined is of critical importance. In this case, it was reported by patients or their parents. However, it is not known how this was reported. For example, obtaining these data face-to-face with a provider has been shown to result in falsely elevated rates of continence, as the patient does not wish to disappoint the provider.
  Moreover, perhaps the biggest concern is with durability. Mean follow-up was only 15 months. Presumably, SIS acts as a template for the in-growth of other tissues. What other tissues grow in? How strong are they? How durable are they? Many stress incontinence procedures have been shown to not stand the test of time. The patients in this series are young and, because of their neurogenic status, they will probably have their continence tested more due to straining than non-neurogenic patients. Although these results are encouraging, they should be considered preliminary. Much longer follow-up is needed.

Dr. Barry A. Kogan
Chief and Professor of Urology and Pediatrics
Albany Medical College
Albany, New York, USA