Extended Experience with High Submuscular Placement of Urological Prosthetic Balloons and Reservoirs: Refined Technique for Optimal Outcomes.

INTRODUCTION: Since 2012, we have routinely placed urological prosthetic balloons and reservoirs in a high submuscular location between the transversalis fascia and rectus abdominis muscle during inflatable penile prosthesis and artificial urinary sphincter surgery. We review our experience of more than 600 high submuscular cases, describe refinements in our technique through time and compare outcomes to prior consecutive space of Retzius prosthetic cases. METHODS: We retrospectively reviewed patients who underwent inflatable penile prosthesis and/or artificial urinary sphincter placement between January 2009 and April 2016. Complications and need for surgical revision were recorded and compared between the 2 placement locations. RESULTS: During the study period 872 prosthetic cases were performed, including 619 high submuscular cases from 2012 to 2016 (inflatable penile prosthesis in 344, artificial urinary sphincter in 275). Of 399 first-time high submuscular implants 54 (14%) required revision, of which 8 (2%) were attributable to the urological balloon or reservoir due to "pain/bother" (4) or herniation (4). Of the 161 space of Retzius urological balloons and reservoirs placed from 2009 to 2011 a similar rate of herniation (3 cases, 1.9%) was noted, although higher rates of deep pelvic complications (3, 1.9%) were noted compared to high submuscular cases (2, 0.5%; p=0.14). Since implementing our refined high submuscular technique, no deep pelvic complications have occurred. CONCLUSIONS: Experience with high submuscular placement of urological balloons and reservoirs confirms that it is safe and well tolerated. With refinements in technique the complication rates are similar in frequency to those with space of Retzius but appear to be minor in nature with negligible risk of visceral or vascular injury.

Simultaneous augmentation cystoplasty and cuff only artificial urinary sphincter in children and young adults with neurogenic urinary incontinence.

PURPOSE: We review our experience with artificial urinary sphincter and augmentation cystoplasty in patients with neurogenic bladder. This is the largest known series to specifically evaluate cuff only artificial urinary sphincter at augmentation cystoplasty. MATERIALS AND METHODS: A total of 18 males underwent simultaneous artificial urinary sphincter and augmentation cystoplasty at our institution between 1982 and 2012, of whom 13 (72%) underwent cuff only artificial urinary sphincter. Outcomes included urinary continence, emptying modality, artificial urinary sphincter status, complications and additional procedures. RESULTS: Of the patients undergoing augmentation cystoplasty and cuff only artificial urinary sphincter 10 (77%) were initially continent. Average time of continence was 52.9 months. Four patients (31%) required no additional procedures and remained continent. Urinary incontinence developed in 3 patients (23%) immediately postoperatively and in 6 (46%) subsequently. Ultimately 9 patients (69%) required conversion to complete artificial urinary sphincter at a mean of 36.9 months postoperatively. Overall 12 patients (92%) were continent at followup. There were no artificial sphincter specific complications in patients undergoing the cuff only procedure with conversion to complete artificial urinary sphincter. After conversion to complete artificial urinary sphincter 3 patients (23%) experienced artificial sphincter specific complications. Reoperation was performed in 10 patients (77%), for 13 total procedures (1.3 per patient). There were no complications with cuff only artificial urinary sphincter and 6 complications with complete artificial urinary sphincter (p = 0.025). Finally, patients undergoing cuff only artificial urinary sphincter requiring revision were younger than those not requiring revision (15.6 vs 30.8 years, p = 0.026). CONCLUSIONS: Simultaneous cuff only artificial urinary sphincter and augmentation cystoplasty appears safe and efficacious in patients with neurogenic bladder, with fewer complications than complete artificial urinary sphincter, and may provide definitive urinary continence in up to a third of patients. This procedure is technically easy, allows for outpatient revision, provides time for the child to mature and may be cost effective in avoiding placement of additional components in this select patient population.

Neutron scattering from equilibrium-swollen networks.

Small-angle neutron scattering measurements were performed on end-linked poly (dimethylsiloxane) (PDMS) networks swollen to equilibrium with d-benzene. Comparison was made with equivalent concentration PDMS solutions. Equilibrium-swollen networks consistently displayed a linear scattering regime at low q followed by a good-solvent-like scaling regime at high q in agreement with the predictions of the Gel Tensile Blob (GTB) model. Data are fit using the unified function modified for the GTB model (3-parameter fit). Equilibrium-swollen networks display a base structural size, the gel tensile-blob size, xi, that was found to be independent of the molecular weight between crosslinks for the series of molecular weights studied, consistent with the predictions of the model. The length of the extended tensile structure, L, can be larger than the length of the fully extended network strand. The predicted scaling relationship for L, L approximately Q(1/2)N(avg), where N(avg) = (1/fN(c)(2) + 1/4N(e)(2), Q is the equilibrium swelling ratio, N(c) is the molecular weight between crosslinks, N(e) is the entanglement molecular weight and f is the crosslink functionality is in agreement with experimental results for the networks studied.