Bastian Amend

Early sacral neuromodulation prevents urinary incontinence after complete spinal cord injury

The study aim was to investigate potential influences on human nerves and pelvic organs through early implantation of bilateral sacral nerve modulators (SNMs) in complete spinal cord injury (SCI) patients during the acute bladder‐areflexia phase.

Effective Treatment of Neurogenic Detrusor Dysfunction by Combined High-Dosed Antimuscarinics without Increased Side-Effects

OBJECTIVES Patients with neurogenic bladder dysfunction demonstrate an insufficient treatment outcome under dosage-escalated monotherapy. With the objectives of continence and normalised bladder pressure, safe and tolerable non-invasive treatment alternatives were evaluated by using combined antimuscarinics. METHODS Twenty-seven patients who were previously registered in a doubled antimuscarinics study were enrolled in this study. The patients demonstrated urodynamic-proven neurogenic bladder dysfunction with incontinence, reduced bladder capacity, and increased intravesical pressure, resulting from spinal cord injury (n=21); spinal cord dysplasia (myelomeningocele; n=3); multiple sclerosis (n=2), and viral encephalomyelitis (n=1). On the basis of the initial study treatment, they were allocated into three groups and treated with two antimuscarinics. Before enrollment, at 4 wk, and at 6 mo, patients underwent urodynamics and recorded bladder diaries, including side-effects. RESULTS In all three groups, significant changes were noted at the 4-wk follow-up. Incontinence events decreased from an average of 7 to 1 event per day. The average median bladder capacity (180-393 ml) and reflex volume (125-335 ml) increased; detrusor compliance also improved (average, 15-33 ml/cm H2O). Seven patients reported side-effects; two discontinued the successful treatment. Two other patients did not reach satisfactory amelioration of the detrusor dysfunction. CONCLUSION With combined high-dosage antimuscarinic medications, 85% of the patients who previously demonstrated unsatisfactory outcome with dosage-escalated monotherapy were treated successfully. The appearance of side-effects was comparable to that of normal-dosed antimuscarinics. Further studies are required to investigate the long-term pharmacological and physiological background of our findings.

The periprostatic autonomic nerves--bundle or layer?

BACKGROUND The functional outcome of a nerve-sparing radical prostatectomy (RP) depends on the knowledge of autonomic nerve distribution in correlation to the prostate. OBJECTIVE Recent literature has focused predominantly on the anterior prostate; this study evaluates the nerve distribution on the entire prostate, using a two-dimensional approach. DESIGN, SETTING, AND PARTICIPANTS From 17 non-nerve-sparing (NS) RP specimens, 77 whole mounted serial sections were immunostained with PGP9.5 and analyzed. INTERVENTION Each prostate half was divided into 12 sectors (three levels: apex, mid-part, base; four courses: anterior, anterolateral, posterolateral, posterior). MEASUREMENTS The extracapsular nerves were counted and classified by size (>200microm or <or=200microm). RESULTS AND LIMITATIONS Approximately two-thirds of the nerves were located in the posterolateral while 26.3/27.0% were located in the anterior and anterolateral. In the anterolateral, along the base-apex direction, the nerves decreased whereas they increased in the posterior. In the anterior, the highest counts were found in the mid-prostate. PGP 9.5 stain helps to determine the extracapsular nerve distribution, however, it does not allow a functional allocation. CONCLUSIONS The nerve course expands from the base in the mid-part to the anterior sector, before it narrows towards the apex in the posterior lateral and posterior sectors. Therefore, it is recommended that the surgeon focus on nerve preservation in particular at the apex, starting in the anterior at the mid section as well as the common posterolateral course.

How does neuromodulation work

Although sacral neuromodulation (SNM) is approved and successfully used for different urological and proctologic functional diseases for the long‐term treatment, less is known about the working mechanisms underlying SNM. This review highlights SNM clinical application, the current data of LUT neuroanatomy and neurophysiology, SNM techniques and its prospective working mechanisms. Functional imaging techniques have facilitated a more detailed insight into the neural network between the central nervous system (CNS) and the lower urinary tract (LUT). In addition to the well‐known factors of the spinal micturition pathway, several pontine (e.g. pontine micturition centre) and suprapontine (e.g. cingulate cortex) regions and their interactions have been identified. An attribution of CNS activity levels to different LUT conditions is possible for the first time. Based on this information, different SNM actions could also have been allocated to different ascending/descending pathways and supraspinal regions, whereas acute SNM especially affects regions of learning activity, chronic SNM might result in CNS plasticity even though clinical effectiveness fades after SNM deactivation. Studies to treat fecal incontinence or to prevent detrusor overactivity in complete spinal cord injured patients support the importance of sympathetic pathways for the action of SNM. Despite increasing knowledge about SNM influence on the CNS, the complexity of its underlying working mechanisms is not understood at all. Further investigations with improved functional imaging techniques will enhance our SNM background. Neurourol. Urodynam. Neurourol. Urodynam. 30:762–765, 2011.

How Does Sacral Modulation Work Best? Placement and Programming Techniques to Maximize Efficacy

Since receiving approval from the US Food and Drug Administration in 1997, sacral neuromodulation (SNM) has become the recommended treatment of urinary urge incontinence, urgency–frequency, nonobstructive urinary retention, and fecal incontinence. The manufacturer has introduced different technical modifications while surgeons and researchers have adapted and published various innovations and alterations of the technique. This review summarizes the current knowledge and recommendations of SNM preoperative decision making, the implantation technique, and available programming parameters and algorithms based on MEDLINE research, manufacturer instructions, and the approach of an experienced neurourological team. The primary steps and technical aspects to optimize SNM efficacy were the introduction of the tined-lead electrode and the development of the InterStim II impulse generator (both developed by Medtronic, Inc., Minneapolis, MN). The initiation of the staged implantation technique for sequential evaluation and implantation with the definitive quadripolar electrode completes the treatment algorithm so that an increased responder rate of SNM for all indications can be achieved.

Surgical Reconstruction for Male-to-Female Sex Reassignment

BACKGROUND The primary challenge of male-to-female reassignment surgery is to create natural-appearing female genitalia with neovaginal dimensions adequate for intercourse, neoclitoris sensitivity, and minimal risk of complications. Surgical positioning is an important component of the procedure that successfully minimizes the risk of morbidity. OBJECTIVE We modified various vaginoplasty techniques to better position the urethral neomeatus in the proper anatomic location to minimize the chance for complications and enhance aesthetic satisfaction. DESIGN, SETTING, AND PARTICIPANTS We retrospectively reviewed data stored in a prospective database for 24 consecutive patients who underwent male-to-female gender reassignment at a German university clinic between January 2007 and March 2011. SURGICAL PROCEDURE First, orchiectomy and penile disassembly are performed with the patient in the supine position. Both corpora cavernosa are resected with the patient in the lithotomy position, and neovaginal construction is accomplished with the incorporation of the penile urethra into the penile shaft skin. The glans is preserved and resized to form the neoclitoris. The assembled neovagina is inverted, inserted into the expanded rectoprostatic space, and secured to the sacrospinous ligament. Scrotal skin is tailored to create the labia. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Complications and patient satisfaction with neovaginal depth, appearance, neoclitoral sensation, and capacity for sexual intercourse were evaluated. RESULTS AND LIMITATIONS The mean neovaginal depth was 11cm (range: 10-14cm); median follow-up was 39.7 mo (range: 19-69 mo). All patients reported satisfactory vaginal functionality. One patient noted stenosis after 4 yr that was histologically confirmed as lichen sclerosus. Neoclitoral sensation was good or excellent in 97% of patients; 33% reported regular intercourse. No major complications were observed. Because this is a retrospective review to describe a complex reconstructive surgery and illustrate these techniques in the accompanying intraoperative surgery-in-motion video, no control group was undertaken. CONCLUSIONS Gender reassignment can be performed with minimal complications using penile skin with incorporated penile urethra and intraoperative repositioning of the patient to achieve adequate neovaginal dimensions for intercourse and neoclitoral sensation.

Introducing a Large Animal Model to Create Urethral Stricture Similar to Human Stricture Disease: A Comparative Experimental Microscopic Study

PURPOSE In this tissue engineering study we investigated urethral stricture formation to evaluate different treatment modalities in the large animal model and validate the most current, comparable effect of human stricture development for successful human clinical application. MATERIALS AND METHODS In 12 male minipigs stricture formation was evaluated by urethrography 1, 8 and 12 weeks after stricture induction by ligation, urethrotomy or thermocoagulation. Normal human urethral and scar tissue of 6 patients was harvested and compared to animal specimens. The effect of urethral damage was investigated for microvessel density and collagen I:III ratio. RESULTS A week after urethrotomy urothelium covered the spongiosum tissue, showing minimal infiltration of lymphocytes and macrophages, and sporadic eosinophil granulocytes. However, increased connective tissue was observed with time as well as urethral luminal narrowing, vascular network loss (decreased microvessel density) and significantly increased collagen with a favorably revised collagen type I:III ratio. The 3 methods of stricture induction resulted in different stricture severity in the animal model (thermocoagulation >ligation >urethrotomy). Porcine urethral samples after thermocoagulation showed a significantly increased collagen I:III ratio (p <0.001), almost equal to that of human urethral stricture specimens. CONCLUSIONS We successfully developed a large animal model in which to study urethral stricture formation by defined iatrogenic intervention. The established animal model advances investigation to evaluate new therapy modalities in a preclinical setting to treat urethral stricture and predict clinical outcome.

Can we prevent incontinence?: ICI‐RS 2011

A review of the current state of research with regard to prevention of incontinence.

Minimally invasive percutaneous nephrolitholapaxy (PCNL) as an effective and safe procedure for large renal stones

Study Type – Therapy (case series)

Minimally Invasive Percutaneous Nephrolithotomy: A Comparative Study of the Management of Small and Large Renal Stones

OBJECTIVE To compare the safety and efficacy of minimally invasive percutaneous nephrolitholapaxy (MIP) between small (<2 cm) and large (>2 cm) renal calculi, because although MIP has proved its efficacy in small lower caliceal stones, the efficacy in large renal calculi has been questioned. MATERIALS AND METHODS The data from 191 consecutive minimally invasive percutaneous nephrolithotomy (MIP) procedures at a single institution from January 2007 to March 2011 were reviewed retrospectively. All stone sizes and complexity were included (98 were <2 cm and 93 were ≥ 2 cm). We performed a comparative analysis of procedures for calculi <2 cm and ≥ 2 cm regarding the stone-free rate, the need for auxiliary procedures, and complications. The Student t test for parametric continuous variables and the chi-square test or Fischers exact test for nominal variables were applied. RESULTS The primary stone-free rate was significantly lower for the large than for the small stones (76.3% vs 90.8%, P = .007), and the secondary stone-free rate after one auxiliary procedure (second-look percutaneous nephrolithotomy, ureterorenoscopy, or shock wave lithotripsy) was not significantly different between the 2 groups (94.6% vs 98.9%, P = .1). The total complication rate was not significantly different (26.9% vs 19.4%, P = .2) between the 2 groups either. Grade III complications occurred in 5.2% of all patients, and no grade IV or V complications were observed. CONCLUSION Using MIP, the total stone-free rate was greater for the small than for the large calculi; however, most patients could be rendered stone-free with the use of one auxiliary procedure. The high success rate and low rate of higher grade complications justify the application of MIP for large stones.