Urodynamic investigations in patients with spinal cord injury: should the ice water test follow or precede the standard filling cystometry?

OBJECTIVES: To evaluate whether the ice water test (IWT) should be performed before or after the standard urodynamic investigation (UDI). PATIENTS AND METHODS: Two cohorts of patients suffering from neurogenic lower urinary tract dysfunction (NLUTD) due to spinal cord injury (SCI) were matched by lesion level and age. The patients of cohort A (n=55, retrospective cohort) underwent the IWT before and the patients of cohort B (n=110, prospective cohort) after standard UDI. The IWT effect on urodynamic parameters has been compared between the two groups using the Mann-Whitney U-test for independent samples. UDI was performed according to good urodynamic practices recommended by the International Continence Society. RESULTS: The mean age of both cohorts was 49 years. Performing the IWT before versus after standard UDI resulted in a significantly lower maximum cystometric bladder capacity (P=0.01), lower incidence of detrusor overactivity (P=0.017) and lower maximum detrusor pressure during IWT (P=0.04). All other urodynamic parameters assessed demonstrated no significant difference (P>0.05). CONCLUSIONS: Our results are in line with findings from animal studies demonstrating a bladder cooling-induced gating effect on the micturition reflex volume threshold on the level of sacral interneurons. Since the IWT is an unphysiological investigation that might significantly bias subsequent urodynamics, we suggest that the IWT should not precede more physiological standard UDI.

[Neuro-urological dysfunction of the lower urinary tract in CNS diseases: pathophysiology, epidemiology, and treatment options]. / Neurourologische Funktionsstörungen des unteren Harntraktes bei Erkrankungen des ZNS : Pathophysiologie, Epidemiologie und Therapieoptionen.

The lower urinary tract (LUT) is regulated by a complex neural network that is subject to supraspinal control. Neurological disorders, especially of the central nervous system (CNS), can rapidly lead to disruption of this control. Multiple sclerosis, Parkinson's disease, multiple system atrophy, and stroke are neurological disorders which quite frequently cause dysfunction of the LUT. With respect to the pathophysiology of bladder dysfunction in CNS diseases there are various hypotheses regarding the individual disorders: disturbances of neural communication between the frontal cortex and pontine micturition center, between the pontine micturition center and the lumbosacral parts of the spinal cord, and between the basal ganglia, thalamus, and anterior cingulate gyrus appear to play a pivotal role in the development of bladder dysfunction. The symptoms and urodynamic presentation of LUT dysfunction can vary considerably depending on the disease and disease progression and can change in the course of the disease. The incidence and prevalence of LUT dysfunctions rise with increasing progression of the underlying neurological disease.Various conservative, minimally invasive, and open surgical procedures are available to prevent harmful sequelae and to improve the quality of life of these patients. As yet, however, few data exist on most of the treatment options in cases of the above-mentioned CNS diseases. Intermittent self-catheterization and antimuscarinic medications are among the most important conservative treatment options. Injection of botulinum neurotoxin type A into the detrusor muscle and increasingly sacral or pudendal neuromodulation are among the most important minimally invasive treatment options. Surgical methods include reconstructive continent or incontinent urinary diversion.When planning therapy the patient's current needs and neurological limitations as well as possible disease progression must be taken into consideration. It is often advisable to consult with and enlist the cooperation of the attending neurologist when planning treatment.

[Sacral neuromodulation for neurogenic bladder dysfunction]. / Sakrale Neuromodulation bei neurogenen Blasenfunktionsstörungen.

Sacral neuromodulation (SNM) represents a promising option for managing treatment-refractory neurogenic bladder dysfunction. It remains to be seen, however, which types of neurogenic bladder dysfunction and which underlying neurological disorders best respond to SNM. Constant improvements in SNM have been achieved and it is now a minimally invasive approach performed under local anesthesia which should be considered before undertaking larger reconstructive procedures. An electrode is implanted in the S3 or S4 sacral foramen and during a test phase lasting for days to weeks the patient keeps a bladder diary to determine whether SNM has provided a relevant benefit. If the results of the test phase are positive, a neuromodulator is implanted in the gluteal area (or more rarely in the abdominal wall).The mechanism of action of SNM has not been completely clarified, but the afferent nerves most likely play a key role. It appears that SNM produces a modulation of medullary reflexes and brain centers by peripheral afferents. The implanted neuromodulation system does not lead to limitation of the patient's activities. However, it should be noted that high-frequency diathermy and unipolar electrocauterization are contraindicated in patients with neuromodulators, that during extracorporeal shock wave lithotripsy the focal point should not be in the direct vicinity of the neuromodulator or the electrode, that ultrasound and radiotherapy in the region of the implanted components should be avoided, that the neuromodulation should be discontinued in pregnancy, and that MRI examinations should only be conducted when urgently indicated and the neuromodulator is turned off.

[Botulinum toxin in nonneurogenic bladder dysfunction]. / Botulinumtoxin bei nichtneurogenen Blasenfunktionsstörungen.

Nonneurogenic overactive bladder with or without detrusor overactivity and/or incontinence is a bothersome symptom for many people. Until a few years ago, it could be treated only with anticholinergic drugs or invasive surgery. Intradetrusor injection with botulinum toxin type A is a minimally invasive alternative therapy option for patients who do not respond to or tolerate anticholinergic treatment. This literature overview summarises the relevant articles on this topic over the last 6 years and provides information on the efficacy, adverse events, currently used dosages, and injection techniques. Overall, a favourable initial efficacy has been observed starting around day 4 after injection and can last up to approximately 31 weeks. Depending on the dose, however, elevated postvoid residual volumes should be anticipated and might require clean intermittent self-catheterisation. The use of botulinum toxin in the urinary bladder is still considered off-label.