An Implantable Device to Regulate Urination through Deep Brain Stimulation (original) (raw)
Related papers
Journal of Medical and Biological Engineering, 2017
Traumatic brain injury (TBI) typically causes permanent brain tissue damage, which leads to permanent severe voiding dysfunction. Urinary retention is often refractory to standard therapies, and most patients require self-catheterization, which results in frequent urinary tract infections and reduces quality of life. Deep brain stimulation (DBS) might be a feasible alternative approach for treating bladder disorders in patients with TBI. In this study, we developed a DBS system with a closed-loop control strategy and determined the feasibility of this DBS system for improving bladder voiding function in a TBI animal model. A prototype of the DBS system was designed, fabricated and integrated with a closed-loop control algorithm based on the real-time external urethral sphincter-electromyogram feedback. A series of animal experiments was conducted to determine whether the feedback algorithm accurately detects the bladder status during cystometric measurements. Subsequent animal experiments were conducted to implement this DBS system and determine the performance of the closed-loop strategy for improving bladder functions in the TBI animal model. We successfully implemented a closed-loop algorithm for DBS control, and the accuracy of the bladder voiding phase detection was [ 90%. Our system significantly improved the voiding efficiency in TBI rats from 22 to 74%. Although the prototype of the DBS feedback system was fabricated with surface-mounted device components and mounted on a 3D printed circuit board, the design principles and animal experience gathered from this research can serve as a basis for developing a new implantable bladder controller in the future.
Neuroprosthetics for SCI Bladder Management: The Argument for Direct Bladder Stimulation
International Journal of Physical Medicine & Rehabilitation, 2014
Implantable neuroprosthetic systems are an important area of practice and research in urinary care for individuals with spinal cord injury (SCI). These devices need to manage three lower urinary tract conditions: urethral sphincter contractions during bladder contractions, an underactive bladder producing poor voiding responses, and neurogenic detrusor overactivity causing urinary incontinence. Two neuroprosthetic approaches have addressed these conditions: sacral anterior root stimulation (SARS) and direct bladder wall stimulation (DBWS). The SARS approach is commercialized for SCI bladder management as the Brindley-Finetech Bladder Control System and is available in Europe. Limitations of this device include invasive surgery and the need for rhizotomy of sacral dorsal (sensory) nerve roots. The DBWS implants produced daily voiding in many SCI individuals, however, clinical use was discontinued primarily because of technical concerns with stimulators and electrodes as well as some cases of poor voiding responses and side effects. These limitations are reviewed as well as efforts to return DBWS to clinical investigations using Permaloc ® Systems (Synapse Biomedical Inc., Oberlin OH). This new neuroprosthetic platform includes mapping and intramuscular electrodes as well as multilead cables and new stimulator devices.
Neuronal Activation in the Periaqueductal Gray Matter Upon Electrical Stimulation of the Bladder
Frontiers in cellular neuroscience, 2018
Reflexes, that involve the spinobulbospinal pathway control both storage and voiding of urine. The periaqueductal gray matter (PAG), a pontine structure is part of the micturition pathway. Alteration in this pathway could lead to micturition disorders and urinary incontinence, such as the overactive bladder symptom complex (OABS). Although different therapeutic options exist for the management of OABS, these are either not effective in all patients. Part of the pathology of OABS is faulty sensory signaling about the filling status of the urinary bladder, which results in aberrant efferent signaling leading to overt detrusor contractions and the sensation of urgency and frequent voiding. In order to identify novel targets for therapy (i.e., structures in the central nervous system) and explore novel treatment modalities such as neuromodulation, we aimed at investigating which areas in the central nervous system are functionally activated upon sensory afferent stimulation of the bladd...
2014
Although sacral anterior root neuromodulation (SARN) has proven to be effective in patients with neurogenic bladder, it is not widely accepted due to the need to conduct a dorsal rhizotomy, and commercially available SARN devices are not usually equipped with a closed-loop controller for the automatic regulation of bladder functions. Therefore, there is still a need for a more effective electrical neuromodulation scheme to restore bladder function. Intravesical pressure (IVP) is the major biosignal that reflects the state of bladder conditions. The present study develops a closed-loop control strategy for improving bladder emptying and verifies its performance using animal experiments. Two channel outputs of electrical currents triggered by IVP-feedback signals were set to automatically regulate a rat's pudendal nerve for selective nerve stimulation and blocking. Under this experimental design, a series of in vivo animal experiments were conducted on anesthetized rats, including the computational characterization of biosignals, the development of an intermittent high-frequency blocking current waveform for blocking the nerve, and verification of the control strategy. Results show that the IVP-feedback control strategy for dual-channel pudendal neuromodulation performed well in animal experiments and could be utilized to selectively stimulate and block the pudendal nerve to augment bladder contraction and restore external urethral sphincter bursting activity to improve bladder emptying. This study demonstrates the feasibility of the IVP-based feedback-control strategy with animal experiments. The results could provide a basis for developing a sophisticated neural prosthesis for restoring bladder function in clinical use or for neurophysiological study.
Neurourology and Urodynamics, 2011
To develop a non-invasive neuromodulation method to regulate bladder activity. Methods: Neuromodulation of bladder activity was investigated in felines with an intact spinal cord under ␣-chloralose anesthesia using a transcutaneous stimulation method with surface electrodes attached to the skin area between the base of the tail and the sciatic notch. Results: The bladder could be either inhibited or excited depending on stimulation frequency and bladder volume. With the bladder distended to induce large amplitude rhythmic isovolumetric bladder contractions, stimulation at a frequency between 5 and 7 Hz significantly suppressed the contractions. Stimulation applied during a cystometrogram (CMG) also increased bladder capacity by 44.3 ± 10.8%. At a frequency between 20 and 40 Hz the inhibitory effect on rhythmic bladder contractions was weak and did not increase bladder capacity during CMG. At low bladder volumes ranging between 60% and 100% of the bladder capacity 20 Hz stimulation-induced small amplitude (21.2 ± 14.6 cmH 2 O) bladder contractions. However, stimulation at 20 Hz induced large amplitude (111.7 ± 22.2 cmH 2 O) bladder contractions at a bladder volume about 100--110% of the bladder capacity after the rhythmic bladder contractions were completely inhibited by the inhibitory 5 Hz stimulation. Conclusions: Both inhibitory and excitatory effects on bladder activity can be obtained in cats using the non-invasive neural stimulation approach. This pre-clinical study warrants a further clinical trial to investigate the possibility of using this non-invasive stimulation method to treat incontinence or urinary retention.
Neurostimulation Strategy for Stress Urinary Incontinence
IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2017
We have developed a percutaneously implantable and wireless microstimulator (NuStim®) to exercise the pelvic floor muscles for treatment of stress urinary incontinence. It produces a wide range of charge-regulated electrical stimulation pulses and trains of pulses using a simple electronic circuit that receives power and timing information from an externally generated RF magnetic field. The complete system was validated in vitro and in vivo in preclinical studies demonstrating that the NuStim can be successfully implanted into an effective, low threshold location and the implant can be operated chronically to produce effective and well-tolerated contractions of skeletal muscle.
Effect of subthalamic deep brain stimulation on the function of the urinary bladder
Annals of Neurology, 2004
Detrusor hyperreflexia is a relevant clinical symptom for patients suffering from Parkinson's disease. In a series of 16 patients, we demonstrated that subthalamic deep brain stimulation has a significant and urodynamically recordable effect leading to a normalization of pathologically increased bladder sensibility.
2010
Lower urinary tract disorders and colorectal diseases like faecal incontinence often are caused by neurological disorders. One solution is functional restoration via the pathways of the nervous system by electrical stimulation of the involved nervous tracts. New basic and clinical research suggest that peripheral and more superficial techniques can successfully applied to correct functional urogenital and anorectal disorders. These new techniques allow more general applicability. This workshop provide the basic science that creates the foundation for electrical stimulation. Latest non-invasive and minimal invasive techniques and results are presented. The aim is to provide insight in basic and clinical electrophysiological mechanisms of electrical stimulation. The objectives are: to understand the basics of electrical stimulation with emphasis on neuroplasticity and therapeutic stimulation; to realise that electrical stimulation can be applied in various forms; to have knowledge abo...
New stimulation strategy to improve the bladder function in paraplegics: chronic experiments in dogs
New neural electrical stimulation strategy, intended to recover the bladder functions, is proposed. Restoring urinary functions allows voluntary bladder voiding, and reduces or even suppresses hyperreflexia. The preliminary stimulation system is composed of subcutaneous implantable stimulators (an implant) and an external device. The implant includes the selective stimulation for bladder voiding, in addition to a new permanent stimulation technique to reduce (or cancel) the bladder hyperreflexia and so cures other related diseases. Permanent stimulation is a low frequency, low amplitude and all day long stimulation that needs to be battery powered. On the other hand, selective stimulation is a bi-frequency, punctual, precise and at a higher amplitude stimulation that is well controlled and powered from the outside. Eight prototypes of the stimulator have been used in an experimental evaluation in dogs to characterize the reliability and functionality of the new implant in a real application environment. Preliminary results of the study show that the proposed stimulation system and the stimulation strategy provide significant improvement for bladder hyperreflexia curing while it confirmed the efficiency of the selective stimulation by means of high frequency blockage.