Abstract
Overactive bladder (OAB) is a medical condition characterized by urgency, with or without urge urinary incontinence, frequency, and nocturia in the absence of genitourinary pathologies or metabolic factors that can explain these symptoms. The current management of OAB is complex, and a wide range of options for conservative treatment have been offered, including bladder training, biofeedback, behavioral changes, oral or intravesical anticholinergic agents, S3 sacral neuromodulation, and peripheral electrical stimulation. The clinical efficacies of these treatments remains an open issue, and several experimental and clinical studies have been carried out during the last years. However, a minor group of OAB patients prove to be refractory to these conservative managements and need further evaluation involving sophisticated urodynamic testing and cystoscopy to carefully define the nature of the lower urinary tract dysfunction and to rule out other causes underlying the symptoms. Thus, the management of refractory OAB, which accounts for 10% of the whole spectrum of OAB, is extremely difficult. The aforementioned therapeutic tools have not always been completely satisfactory in these refractory OAB. Here, the author reviews the mechanism of micturition reflex and the current therapies, particularly highlighting the potential benefit of neuromodulation for refractory OAB.
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