Sacral Nerve Root Stimulation for the Treatment of Urge Incontinence and Detrusor Dysfunction Utilizing a Cephalocaudal Intraspinal Method of Lead Insertion: A Case Report

Sacral nerve root stimulation (SNRS) is known to be effective in the treatment of pelvic motor dysfunction( 1 - 4 ). Bladder and urethral motor disorders commonly treated include urinary urge incontinence, voiding/detrusor dysfunction, and urgency/frequency syndromes. To date, neurostimulation specific to bladder and urethral dysfunction has applied a unilateral, trans‐sacral approach. (Interstim, Medtronic, Minneapolis, MN) Despite some success, this method has been associated with technical failures in maintaining electrode position( 5 , 6 ). As an alternative, this case report describes the selective epidural application of a cephalocaudal (“retrograde”) lead insertion method in a patient with severe detrusor dysfunction and urinary urge incontinence( 7 ).     

Optogenetic Neuromodulation of the Urinary Bladder

ObjectivesNerve stimulation and neuromodulation have become acceptable interventions for bladder dysfunction. However, electrical stimulation indiscriminately affects all types of cells and can lead to treatment failure and off-target effects. In recent years, advancement of knowledge of optogenetics provides a powerful tool to enable precise, minimally invasive neuromodulation.Materials and MethodsIn this review, we introduce basic knowledge about optogenetics; discuss the progression of engineered opsins, gene-targeting methods, and light-delivery approaches; we also summarize the application of optogenetics in neuromodulation of the bladder and discuss the possible clinical translation in the future.Results and ConclusionOptogenetics offers a powerful tool to investigate the neural circuit of bladder storage and voiding and provides a promising approach for manipulating neurons and muscles. It is possible to achieve coordinated modulation of the bladder and its sphincter through a “closed-loop” system. Optogenetics neuromodulation could also be applied in urinary bladder control in the clinic in the future.     

Selective Nerve Root Stimulation (SNRS) for the Treatment of Intractable Pelvic Pain and Motor Dysfunction: A Case Report

Interstitial cystitis is the most disabling nonmalignant disorder seen by urologists. Chronic debilitating urinary bladder symptoms (severe pain and pelvic floor muscular dysfunction) often progress despite maximal medical attempts at management. Although the exact cause remains unknown, a neuropathic etiology has recently been suggested( 1 , 2 ). This case report describes the use of Selective Nerve Root Stimulation (SNRS) for the treatment of intractable pelvic pain and motor dysfunction in a patient with Interstitial cystitis (IC).     

A Study of Electrode Placement at the Cervical and Upper Thoracic Nerve Roots Using an Anatomic Trans-Spinal Approach

Objective. Since 1996 we have placed temporary catheters at the cervical nerve roots in chronic pain patients for the treatment of radiculopathy and complex regional pain syndrome. We investigated the possibility of placing electrodes both at the cervical spinal nerve and dorsal root ganglion for the purpose of neuromodulation. Methods. Anatomic and technical feasibility studies were performed on 4 human cadavers to examine the placement of electrodes at the cervical nerve roots. We proposed a novel trans-spinal approach to the cervical and upper thoracic nerve roots. We tested various approaches and insertion techniques. We collected radiographic images of the essential steps involved in this technique. Results. Successful placement was accomplished in 3 of the 4 cadavers at the C3, C4, C5, C6, C7, C8, T1, and T2 nerve roots. For placement at C5 to T2, we used a trans-spinal approach entering at the corresponding contralateral interlaminar space. However, due to the anatomy of the cervical nerve roots, vertebral artery, cervical plexus, and occiput, it was necessary to use a different technique for the upper cervical nerve roots. For placement at the C3 and C4 nerve roots, we made the initial insertion between the C1 and C2 lamina using curved needles which were advanced in a caudal direction transversing the median plane of the spine to arrive at the contralateral inter vertebral foramen of either C3 or C4. We were unable to cannulate either C1 or C2 in any of the cadavers. The required equipment included fluoroscopy, contrast dye, directable guide wires, electrodes, and curved needles. Conclusions. In human cadavers, a percutaneous technique was successful in the placement of neurostimulator electrodes at the cervical and upper thoracic nerve roots using a novel trans-spinal approach. New smaller electrode systems that can be placed in a transforaminal position safely may be needed.     

Percutaneous Neuromodulation of the Brachial Plexus and Sciatic Nerve for the Treatment of Acute Pain Following Surgery: Secondary Outcomes From a Multicenter,Randomized, Controlled Pilot Study

ObjectivesWe recently reported that percutaneous peripheral nerve stimulation (PNS or “neuromodulation”) decreased pain and opioid consumption within the first two weeks following ambulatory surgery. However, the anatomic lead locations were combined for the analysis, and benefits for each location remain unknown. We therefore now report the effects of percutaneous PNS for brachial plexus and sciatic nerve leads separately.Materials and MethodsBefore surgery, leads were implanted percutaneously to target the brachial plexus (N = 21) for rotator cuff repair or sciatic nerve (N = 40) for foot/ankle surgery, followed by a single injection of local anesthetic. Postoperatively, subjects were randomized in a double masked fashion to 14 days of electrical stimulation (N = 30) or sham/placebo (N = 31) using an external pulse generator. The primary outcome of interest was opioid consumption and pain scores evaluated jointly. Thus, stimulation was deemed effective if superior on either outcome and at least noninferior on the other.ResultsFor brachial plexus leads, during the first seven postoperative days pain measured with the numeric rating scale in participants given active stimulation was a median [interquartile range] of 0.8 [0.5, 1.6] versus 3.2 [2.7, 3.5] in patients given sham (p < 0.001). For this same group, opioid consumption in participants given active stimulation was 10 mg [5, 20] versus 71 mg [35, 125] in patients given sham (p = 0.043). For sciatic nerve leads, pain scores for the active treatment group were 0.7 [0, 1.4] versus 2.8 [1.6, 4.6] in patients given sham (p < 0.001). During this same period, participants given active stimulation consumed 5 mg [0, 30] of opioids versus 40 mg [20, 105] in patients given sham (p = 0.004). Treatment effects did not differ statistically between the two locations.ConclusionsAmbulatory percutaneous PNS of both the brachial plexus and sciatic nerve is an effective treatment for acute pain free of systemic side effects following painful orthopedic surgery.