Initial bladder filling sensation, first and strong desire to void are subjective perceptions that occur periodically during the urine storage mode of bladder function, representing sensory input from the lower urinary tract. To our knowledge methods for evaluating sensory bladder function are not available. We studied a simple electrophysiological procedure for the objective assessment of bladder sensations using sympathetic skin responses and surface pelvic floor electromyography.
Informed consent was provided by 8 healthy male subjects, who were administered 20 mg. furosemide and 1 l. fluid to drink. Palmar and plantar sympathetic skin responses, and surface pelvic floor electromyogram were continuously recorded during bladder filling, voluntary pelvic floor contraction and voiding.
First desire to void evoked simultaneous sympathetic skin responses and pelvic floor contractions. This pattern appeared periodically with the desire to void sensation as well as with strong desire to void at maximum bladder capacity and it correlated well with the subjective sensation of the subjects. Voluntary pelvic floor contraction decreased the subjective intensity of the desire to void sensation as well as sympathetic skin response activity for the same short period. During voiding sympathetic skin responses almost complete absence of sympathetic skin responses was observed.
Sensations arising from the bladder induce combined activation of sympathetic skin responses and pelvic floor activity. This coherence indicates synchronized activation and inactivation of the autonomic and somatic pathways necessary for appropriate urine storage and coordinated voiding. Our observations may introduce a new approach for objectively assessing subjective sensations arising from the urinary tract.
"Making use of the fMRI technique, the aim of this study was to investigate the brain structures involved in voluntary control of bladder function: in colloquial terms, to answer the question: bWhich areas in the brain are involved in the voluntary control of the micturition?Q Derived from earlier urology study (Reitz et al., 2003), it is hypothesized that these areas' activity triggered by pelvic floor muscle contraction will increase when bladder is full, since the filled bladder has almost no room for urine holding; therefore any pelvic floor muscle action would dramatically arouse desire to void and suppression of such desire, since it is not allowed to urinate in the scanner, thereby we have established a nonvoiding model (i.e., active pelvic floor muscle contraction with full bladder to induce stronger desire to void and micturition reflex inhibition, since the subject is not allowed to urinate) of inhibitory bladder control. The model involves the performance of repetitive pelvic floor muscle contraction in alternation with periods of rest under full (FBC)-and empty (EBC)-bladder conditions. "
[Show abstract][Hide abstract] ABSTRACT: We have learned that micturition is comprised of two basic phases: storage and emptying; during bladder emptying, the pontine and periaqueductal gray (PAG) micturition center ensures coordinated inhibition of striated sphincter and pelvic floor muscles and relaxation of the internal urethral sphincter while the detrusor muscle contracts. Due to several disorders of the brain and spinal cord, the achieved voluntary control of bladder function can be impaired, and involuntary mechanisms of bladder activation again become evident. However, little has been discovered so far how higher brain centers strictly regulate the intricate process of micturition. The present functional magnetic resonance imaging (fMRI) study attempted to identify brain areas involved in such voluntary control of the micturition reflex by performing functional magnetic resonance imaging during a block design experiment in 12 healthy subjects. The protocol consisted of alternating periods of rest and pelvic muscle contraction during empty-bladder condition (EBC) and full-bladder condition (FBC). Repeated pelvic floor muscle contractions were performed during full bladder to induce a stronger contrast of bladder sensation, desire to void and inhibition of the micturition reflex triggering, since the subjects were asked not to urinate. Empty-bladder conditions were applied as control groups. Activation maps calculated by contrast of subtracting the two different conditions were purposed to disclose these brain areas that are involved during the inhibition of the micturition reflex, in which contrast, the SMA, bilateral putamen, right parietal cortex, right limbic system, and right cerebellum were found activated. The combined activation of basal ganglia, parietal cortex, limbic system, and cerebellum might support the assumption that a complex visceral sensory-motor program is involved during the inhibitory control of the micturition reflex.
[Show abstract][Hide abstract] ABSTRACT: For the diagnosis of neurogenic bladder, in addition to clinical assessment, neurophysiologic testing may be useful. Neurophysiologic
tests are more useful in patients with sacral compared with suprasacral disorders. Anal sphincter electromyography (EMG) is
the most useful diagnostic test, particularly for focal sacral lesions and atypical parkinsonism. Another clinically useful
method that tests the sacral segments and complements EMG is the sacral (penilo/clitoro-cavernosus) reflex. Kinesiologic EMG
is useful to demonstrate detrusor sphincter dyssynergia. Somatosensory-evoked potential and motor-evoked potential studies
may be useful to diagnose clinically silent central lesions. The utility of cortical somatosensory-evoked potential in bladder/urethra
stimulation is limited by technical difficulties that can be partially overcome by the concomitant recording of a palmar sympathetic
skin response. Sympathetic skin response recorded from the saddle region is also useful for testing the lumbosacral sympathetic
system. A clinically useful neurophysiologic test for evaluating the sacral parasympathetic system is still lacking.
KeywordsElectromyography-Lower urinary tract-Motor-evoked potentials-Neurogenic bladder-Somatosensory-evoked potentials-Sympathetic skin response-Voiding
Current Bladder Dysfunction Reports 06/2010; 5(2):79-86. DOI:10.1007/s11884-010-0048-5
[Show abstract][Hide abstract] ABSTRACT: In most spinal cord injured (SCI) patients the objective assessment of afferent neuronal pathways from the lower urinary tract and the recording of a disturbed urethral sensation and/or desire to void are still difficult. Viscerosensory evoked potentials (VSEPs) might be helpful, but they remain technically difficult to obtain and interpretation is delicate. As a new approach, sympathetic skin response (SSR) of the hand and foot were recorded after electrical stimulation of the posterior urethral mucosa. This technique should allow assessment of the integrity or deterioration of the autonomic afferent pathway.
A total of 20 males and 8 females with SCI somatosensory incomplete 15, somatosensory complete 13 and 6 healthy male volunteers were prospectively examined. During urodynamic examination electrical stimulation (single square pulses of 0.2 ms, 2 to 3-fold sensory threshold, 60 mA in complete SCI patients) of the posterior urethra/bladder neck was performed using a bipolar electrode inserted into a microtip pressure catheter. SSR recordings of the right palm and sole were simultaneously taken using surface electrodes and were analyzed by an electromyography unit. Patient reports on evoked urethral sensations at individual sensory thresholds were simultaneously noted. Additionally, well-known electrophysiological measurements such as pudendal sensory evoked potential and urethral VSEP were recorded to check clinical assessed somatosensory and viscerosensory status, and to compare SSR results with these conventional methods.
Electrical stimulation of the posterior urethra evoked clear urethral sensation and SSRs in normal subjects. In 14 of 15 sensory incomplete SCI patients with disturbed urethral sensation SSRs could be recorded as well. Electrically evoked urethral sensations resembled the subjective desire to void at full bladder reported by controls and patients. In 13 sensory complete SCI patients with loss of any urethral sensation SSRs could not be recorded even at maximal electrical stimulation strength. All subjects with electrically induced urethral sensation had positive evoked (supralesional) SSRs of the hand. However, none of the patients with absent urethral sensation presented SSRs. Simultaneously recorded VSEPs could not be recorded clearly in 5 patients and 2 control subjects, whereas SSRs delivered clear results in all controls and patients, matching their reports.
SSR recordings above a spinal lesion level after urethral electrostimulation might provide a useful and technically simple objective diagnostic tool to assess integrity of autonomic (visceral) afferent nerves from the lower urinary tract. Somatosensory deficits are not always paralleled by viscerosensory loss and vice versa. In this study SSRs were superior to VSEPs, the latter being more difficult to record. The subjective sensations reported by subjects during stimulation could be confirmed in an objective way in 100% of cases by positive/negative SSR findings.
The Journal of Urology 04/2004; 171(3):1156-60. DOI:10.1097/01.ju.0000111809.81966.8b · 4.47 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.