Dorsal genital nerve stimulation in patients with detrusor overactivity: a systematic review.

This study evaluates the outcome of trials to stimulate the dorsal genital nerve (DGN) in patients with lower urinary tract dysfunction. The aim of most studies was to suppress detrusor overactivity in patients with overactive bladder (OAB) syndrome by DGN stimulation. A literature search was performed using Pub Med, Web of Science, and Scopus databases (1980 to April 2012) for clinical trials of DGN stimulation in patients with detrusor overactivity. Seventeen studies were found in the literature. In the studies, different patterns of DGN stimulation were applied. The patterns were either continuous, conditional, or semi-conditional; on an acute or on a chronic basis. DGN stimulation lead to improvement of bladder capacity and reduction in urgency and/or incontinence episodes in many patients. The outcomes of conditional stimulation were comparable to continuous stimulation with respect to improvement of bladder capacity. The publications give evidence that DGN stimulation increases bladder capacity and suppresses involuntary detrusor contractions. Implantable DGN stimulation electrodes can open the way for more prolonged studies in larger patient groups to assess the effectiveness of chronic DGN stimulation in patients with OAB syndrome. Chronic DGN stimulation seems to be of value in the management of OAB syndrome.

Non-invasive techniques in the diagnosis of bladder storage disorders.

AIMS: To review clinical studies thus have been conducted to develop non-invasive diagnostic tools in the storage phase of the micturition cycle. METHODS: Pub Med and Web of Science searches were carried out. The search covered the published data of non-invasive diagnostic techniques for detrusor overactivity (DO) and/or low compliance bladder in patients with urinary storage symptoms. The patho-physiological and clinical relevance of these methods were addressed. Diagnostic accuracy of these techniques was scrutinized. RESULTS: Eighteen studies were included in the review. Ultrasonography and biomarkers were the most investigated techniques in the diagnosis of storage disorders. Assessment of diagnostic accuracy was possible in four studies. The heterogeneity in data reporting was too high to conduct a meta-analysis. Ultrasonographic parameters and cut-off values have been developed to define DO; such as bladder wall thickness (BWT), detrusor wall thickness and bladder weight. The likelihood ratio of vaginal ultrasonography in measurement of BWT was good. Guidelines are currently developing to standardize the methodologies applied in these techniques. Laboratory biomarkers of DO are gaining more attention recently, but their specificity for DO should be carefully defined. Near infrared spectroscopy (NIRS) is potential non-invasive diagnostic method that is able to detect the DO episodes in real time. However, a solution needs to be found for motion artifacts in this technique. CONCLUSION: Non-invasive diagnostic techniques for storage disorders show limited progress with some limitations. Yet these techniques still cannot replace the standard filling cystometry in standard clinical practice.

Feasibility of noninvasive near-infrared spectroscopy to diagnose detrusor overactivity.

INTRODUCTION: Near-infrared spectroscopy (NIRS) is an optical technology able to detect the hemodynamic changes in biological tissues. Our objective was to determine the feasibility of applying NIRS in the noninvasive diagnosis of detrusor overactivity (DO). PATIENTS AND METHODS: Comparative analysis was performed on 39 involuntary detrusor contractions (IDC) from 23 filling cystometries with simultaneous noninvasive NIRS of the bladder in 14 patients with DO. Motion artifacts were checked for via surface EMG of the abdominal muscles. RESULTS: Thirty-nine IDC were obtained. The median amplitude of rise in detrusor pressure at DO was 48 cm H(2)O (range: 5-219). The median filling volume at DO was 148 ml (range: 9-531). NIRS curves demonstrated apparently significant deviations from baseline in 35 of 39 (90%) DO episodes. All onsets of NIRS deviations occurred within the time period of the IDC with a mean delay of 3 s (range: 0-9). CONCLUSION: NIRS can be a potential tool for the noninvasive diagnosis of DO.

Scrotal ultrasonographic findings in obese infertile patients and their correlations to semen and hormonal profile.

OBJECTIVE: The aim of this prospective study was to compare scrotal ultrasonographic findings in obese and normal weight infertile men and correlate these findings with semen parameters and hormonal profile. MATERIAL AND METHODS: A total of 188 men presented for infertility evaluation were included in this study. They were divided according to body mass indices into obese (n=96) and normal weight infertile patients (n=92). Basic infertility evaluation, semen analysis and scrotal duplex ultrasound examination in addition to measurement of serum levels of follicular stimulating hormone, testosterone and estradiol were done for all cases. The ratio between testicular size measured by scrotal ultrasound and body mass index were calculated. RESULTS: Any significant differences were not observed in semen parameters, serum levels of follicular stimulating hormone and testosterone between obese and normal weight infertile men (p>0.05). Serum estradiol level was significantly higher in obese than normal weight infertile men (p<0.001). There is significant increase in subclinical varicocele, hydrocele and testicular microlithiasis detected by scrotal ultrasound in obese infertile men than nonobese patients (p<0.05). Despite having comparable testicular size detected on scrotal ultrasound, infertile obese men had significantly lower total testicular volume to body mass index ratio and this ratio correlated positively with semen volume, sperm concentration, total sperm count and serum testosterone but negatively with serum follicular stimulating hormone and estradiol levels. CONCLUSION: We therefore conclude that the incidence of subclinical varicocele, hydrocele and testicular microlithiasis was higher in obese infertile patients and the ratio between testicular volume assessed by scrotal ultrasound and body mass index may be a new parameter that correlates with subfertility status in these men.

Subject-Controlled, On-demand, Dorsal Genital Nerve Stimulation to Treat Urgency Urinary Incontinence; a Pilot.

OBJECTIVES: To evaluate the effect of subject-controlled, on-demand, dorsal genital nerve (DGN) stimulation on non-neurogenic urgency urinary incontinence (UUI) in a domestic setting. MATERIALS AND METHODS: Non-neurogenic patients >18 years with overactive bladder symptoms and UUI were included. Exclusion criteria were mainly stress urinary incontinence. Patients underwent 1 week of subject-controlled, on-demand, DGN stimulation, delivered by a percutaneously placed electrode near the DGN connected to an external stimulator (pulse-rate 20 Hz, pulse-width 300 µs). Patients activated the stimulator when feeling the urge to void and stimulated for 30 s. The amplitude was set at the highest tolerable level. A bladder diary including a severity score of the UUI episodes/void (scores: 0 = none, 1 = drops, 2 = dashes, 3 = soaks) and a padtest was kept 3 days prior to, during, and 3 days after the test period. The subjective improvement was also scored. RESULTS: Seven patients (4 males/3 females) were enrolled, the mean age was 55 years (range 23-73). Six completed the test week. In the remaining patient the electrode migrated and was removed. 5/6 finalized the complete bladder diary, 1/6 recorded only the heavy incontinence episodes (score = 3). 4/6 completed the padtest. In all patients who finalized the bladder diary the number of UUI episodes decreased, in 3/5 with ≥60%. The heavy incontinence episodes (score = 3) were resolved in 2/6 patients, and improved ≥80% in the other 4. The severity score of the UUI episodes/void was improved with ≥ 60% in 3/5 patients. The mean subjective improvement was 73%. CONCLUSION: This feasibility study indicates that subject-controlled, on-demand DGN stimulation using a percutaneously placed electrode is possible over a longer time period, in a home setting, with a positive effect on non-neurogenic overactive bladder symptoms with UUI. Although the placement is an easy procedure, it is difficult to fixate the electrode to keep it in the correct position. Improvements in hardware, like a better fixated electrode and an easy to control stimulator, are necessary to make SODGNS a treatment possibility in the future.

Imaging assessments of lower urinary tract dysfunctions: Future steps.

Urodynamic tests are the standard diagnostic method for lower urinary tract dysfunctions (LUTD). However, these tests are invasive. The current review describes the noninvasive imaging techniques that have been used to monitor LUTD. The main imaging technologies that have been applied in diagnosing LUTD were 2D ultrasonography, Doppler ultrasonography, and near-infrared spectroscopy (NIRS). Ultrasonographic parameters, such as bladder wall thickness (BWT), detrusor wall thickness (DWT), and ultrasound-estimated bladder weight (UEBW), have been proposed as surrogates for bladder outlet obstruction (BOO) or detrusor overactivity (DO). Few studies have reported diagnostic cut-offs in diagnosing BOO or DO; thus, there is still a need to standardize the measurement method. NIRS can detect the hemodynamic changes related to DO and BOO in real-time, which could be advantageous in clinical practice, but the liability of NIRS to motion artefacts is a limitation. Bladder strain imaging in real-time using 2D ultrasound enables noninvasive estimation of the dynamic changes in the bladder wall during voiding. Many imaging techniques have been used to monitor the urinary bladder during the storage and voiding phases of the micturition cycle. These techniques were either static [i.e., measuring fixed parameters, such as BWT, DWT, UEBW, and intravesical prostatic protrusion (IVPP)] or dynamic (monitoring the structural and hemodynamic changes in the bladder wall in real-time). These techniques are currently being developed and standardized for potential use in diagnosing LUTD in clinical practice.

Near-infrared spectroscopy of the urinary bladder during voiding in men with lower urinary tract symptoms: a preliminary study.

OBJECTIVES: To determine the difference in response of NIRS of the bladder during voiding between men with and without BOO.LUTS. METHODS: A prospective, case series, study included 36 men with LUTS. Patients completed the IPSS questionnaire; prostate volumes were measured sonographically. Patients underwent pressure flow study (PFS) with simultaneous NIRS of the bladder. Amplitudes of HHb, O2Hb, and Hbsum were calculated at Qmax, relative to baseline. Patients were urodynamically classified as obstructed and unobstructed. Recursive partition analysis (RPA) was performed to reclassify patients using NIRS amplitudes, followed by combined data of NIRS amplitudes, prostate volume, IPSS, and Qmax to determine the best predictor(s) of BOO. RESULTS: PFS classified 28 patients as obstructed and 8 as unobstructed. The median HHb amplitude was significantly higher in obstructed group. RPA of NIRS amplitudes correctly reclassified 89% of patients [AUC: 0.91]. RPA of the combined IPSS, prostate volume, PVR, and Qmax correctly reclassified 72% of patients [AUC: 0.84]. When NIRS amplitudes were added to this combination, RPA revealed a significantly (P < 0.01) higher rate of correct reclassification in 89% of patients with 89.3% sensitivity and 88% specificity for obstruction [AUC: 0.96]. CONCLUSION: NIRS data can be of diagnostic value for BOO in men with LUTS.

Near-infrared spectroscopy: a novel, noninvasive, diagnostic method for detrusor overactivity in patients with overactive bladder symptoms--a preliminary and experimental study.

BACKGROUND: Near-infrared spectroscopy (NIRS) is an optical technology. It detects the hemodynamic changes in tissues via noninvasive measurement of changes in the concentration of tissue chromophores such as oxyhemoglobin (O(2)Hb) and deoxyhemoglobin (HHb). Involuntary bladder contractions may cause changes detectable by NIRS. OBJECTIVE: To address the accuracy and reproducibility of NIRS to detect the hemodynamic effects of detrusor overactivity (DO). DESIGN, SETTING, AND PARTICIPANTS: A prospective cohort study was carried out on 41 patients with overactive bladder symptoms. MEASUREMENTS: Forty-one patients underwent one or more filling cystometries with simultaneous NIRS of the bladder. The separated graphs representing both tests were presented to three urodynamicists on two occasions, 3 wk apart. The graphs showed curves with and without DO episodes with the bladder sensations marked. Thirteen of 47 graphs (28%) with DO and 16 of 58 graphs (28%) without DO were excluded due to motion artifacts. The urodynamicists marked pressure changes suggestive of DO on the cystometry curves. For NIRS curves they marked definite deviations from baseline. The sensitivity and specificity of NIRS for DO were determined. The inter- and intraobserver agreements were determined. RESULTS AND LIMITATIONS: Valid data from 33 of 41 patients (80%) were included in the analysis. The interobserver agreement to trace the effect of DO on NIRS curves was "substantial" (κ(f)>0.6). The sensitivity of the Hb(sum) (O(2)Hb+HHb) curves for DO was 62-97% with a specificity of 62-79% (area under the curve [AUC]: 0.80-0.82; p<0.001). O(2)Hb curves had 79-85% sensitivity and 82-91% specificity for DO (AUC: 0.80-0.85; p<0.001). The sensitivity and specificity of the HHb curves for DO were 71-82% and 77-82%, respectively (AUC: 0.73-0.84; p<0.001). These values represent the performance of NIRS in the data sample that is not contaminated with motion artifacts; they are not representative of a general clinical setting. CONCLUSION: NIRS is a potential noninvasive, reproducible, diagnostic method to detect DO.