Clinical trials in neuromodulatory treatment of drug-resistant hypertension and the need for spinal cord stimulation trials: a PRISMA systematic review.

Background: Drug-resistant hypertension affects approximately 9-18% of the United States hypertensive population. Recognized as hypertension that is resistant to three or more medications, drug-resistant hypertension can lead to fatal sequelae, such as heart failure, aortic dissection, and other vast systemic disease. The disruption of the homeostatic mechanisms that stabilize blood pressure can be treated procedurally when medication fails.

Hematoma-induced Twiddler-like phenomenon as a presentation of DBS hardware failure: Case report.

Deep brain stimulators (DBS) may fail for a multitude of reasons. We present a 79-year-old Parkinson's disease patient who suffered a DBS failure following impulse generator (IPG) replacement surgery due to the IPG flipping within an expanded capsular pocket. This creation of the pocket was unintentional, and the pocket formed around an undiagnosed postoperative hemorrhage.

Identifying the therapeutic zone in globus pallidus deep brain stimulation for Parkinson's disease.

Objective: The globus pallidus internus (GPI) has been demonstrated to be an effective surgical target for deep brain stimulation (DBS) treatment in patients with medication-refractory Parkinson's disease (PD). The ability of neurosurgeons to define the area of greatest therapeutic benefit within the globus pallidus (GP) may improve clinical outcomes in these patients. The objective of this study was to determine the best DBS therapeutic implantation site within the GP for effective treatment in PD patients.

Management of Cerebral Herniation Secondary to Lead Encephalopathy: A Case Report.

Background: Adult lead encephalopathy is a rare but critical condition to recognize in modern healthcare settings. Few reports have described the medical and neurosurgical management of severe adult lead encephalopathy.

Case Presentation: A 22 year old woman presented with severe headache, anemia, vomiting, 40-lb weight loss, and constipation.

A novel local field potential-based functional approach for targeting the centromedian-parafascicular complex for deep brain stimulation.

Background: The centromedian-parafascicular (Cm-Pf) complex of the thalamus is a common deep brain stimulation (DBS) target for treatment of Tourette syndrome (TS). Currently, there are no standardized functional intraoperative neurosurgical targeting approaches. Collectively, these issues have led to variability in DBS lead placement.

Hidden Error in Optical Stereotactic Navigation Systems and Strategy to Maximize Accuracy.

Background: Optical neuronavigation has been established as a reliable and effective adjunct to many neurosurgical procedures. Operations such as asleep deep brain stimulation (aDBS) benefit from the potential increase in accuracy that these systems offer. Built into these technologies is a degree of tolerated error that may exceed the presumed accuracy resulting in suboptimal outcomes.

Globus Pallidus Internus (GPi) Deep Brain Stimulation for Parkinson's Disease: Expert Review and Commentary.

Introduction: The globus pallidus internus (GPi) region has evolved as a potential target for deep brain stimulation (DBS) in Parkinson's disease (PD). DBS of the GPi (GPi DBS) is an established, safe and effective method for addressing many of the motor symptoms associated with advanced PD. It is important that clinicians fully understand this target when considering GPi DBS for individual patients.

Lead Repositioning Guided by Both Physiology and Atlas Based Targeting in Tourette Deep Brain Stimulation.

Background: The centromedian (CM) region of the thalamus is a common target for deep brain stimulation (DBS) treatment for Tourette Syndrome (TS). However, there are currently no standard microelectrode recording or macrostimulation methods to differentiate CM thalamus from other nearby structures and nuclei.

Case Report: Here we present a case of failed conventional stereotactic targeting in TS DBS.

Spinal Cord Stimulation for Visceral Pain: Present Approaches and Future Strategies.

Introduction: The introduction of successful neuromodulation strategies for managing chronic visceral pain lag behind what is now treatment of choice in refractory chronic back and extremity pain for many providers in the United States and Europe. Changes in public policy and monetary support to identify nonopioid treatments for chronic pain have sparked interest in alternative options. In this review, we discuss the scope of spinal cord stimulation (SCS) for visceral pain, its limitations, and the potential role for new intradural devices of the type that we are developing in our laboratories, which may be able to overcome existing challenges.

Dissociation between reduced pain and arterial blood pressure following epidural spinal cord stimulation in patients with chronic pain: A retrospective study.

Purpose: Acute pain and resting arterial blood pressure (BP) are positively correlated in patients with chronic pain. However, it remains unclear whether treatment for chronic pain reduces BP. Therefore, in a retrospective study design, we tested the hypothesis that implantation of an epidural spinal cord stimulator (SCS) device to treat chronic pain would significantly reduce clinic pain ratings and BP and that these reductions would be significantly correlated.

Intervertebral Displacement of the Thoracic Spine with and without Loading: Radiographic and in Vitro Measurements.

Background: We are developing an intradural approach to spinal cord stimulation, where the thin electrode array is affixed stably to the underside of the thoracic spinal dura mater without leakage of cerebrospinal fluid. As part of the design and testing process, we sought to evaluate the potential risk of inadvertent contact of the array with the pial surface of the spinal cord during variations in spinal loading.

Methods: As part of the risk assessment process, a 2-part study was undertaken.

In Vivo Testing of a Prototype Intradural Spinal Cord Stimulator in a Porcine Model.

Background: Chronic midline low back pain is the number one reason for disability in the United States despite the prolific use of medical and surgical interventions. Notwithstanding the widespread use of epidural spinal cord stimulators (SCSs), there remains a large portion of the population with inadequate pain control thought to be because of the limited volume of stimulated neural tissue. Intradural SCSs represent an underexplored alternative strategy with the potential to improve selectivity, power efficiency, and efficacy.

A new device to improve target localization for transcranial magnetic stimulation therapy.

Background: Accurate identification of cranial midline structures is essential for many targeting techniques that use repetitive transcranial magnetic stimulation (rTMS), including the Beam F3 method used for depression treatment.

Objective: Evaluate whether a novel, laser-sighted device will assist with more accurate identification of the cranial midline relative to standard scalp-based measurement procedures.

Methods: Three trained TMS technicians performed repeated scalp-based measurements to identify the inion and vertex on five subjects (n = 54 measurements).

Predictability of vascular conflict by MRI in trigeminal neuralgia.

Objective: Magnetic resonance imaging (MRI) has been investigated extensively in its success or failure to identify preoperative vascular compression in patients with trigeminal neuralgia (TN). To this end, we reviewed our case load to evaluate the concordance or discordance between preoperative MRI and intraoperative findings.

Patients And Methods: Sixty-nine patients with Type 1 TN and retrievable MRI images, operative reports, and intraoperative photographs were retrospectively reviewed.

The Wishbone: A Cranial Midline Localizing Device.

Objective: The Wishbone device is designed to enable surgeons to quickly and accurately localize the cranial midline. It is intended to be of particular use when localizing the burr hole site during posterior ventriculoperitoneal shunt (VPS) surgery.

Methods: The Wishbone is a simple mechanical device with 2 adjustable caliper arms that reversibly attach to a patient's left and right external auditory canals.

Intradural Spinal Cord Stimulation: Performance Modeling of a New Modality.

Intradural spinal cord stimulation (SCS) may offer significant therapeutic benefits for those with intractable axial and extremity pain, visceral pain, spasticity, autonomic dysfunction and related disorders. A novel intradural electrical stimulation device, limited by the boundaries of the thecal sac, CSF and spinal cord was developed to test this hypothesis. In order to optimize device function, we have explored finite element modeling (FEM).

Durotomy Surrogate and Seals for Intradural Spinal Cord Stimulators: Apparatus and Review of Clinical Methods and Materials.

Introduction: We are developing a novel intradural spinal cord stimulator for treatment of neuropathic pain and spasticity. A key feature is the means by which it seals the dura mater to prevent leakage of cerebrospinal fluid (CSF). We have built and employed a test rig that enables evaluation of candidate seal materials.

Many caregivers of persons with memory loss or Alzheimer's disease are unaware of the abilities of their persons with AD to recall their drugs and medical histories.

Background: Caregiver awareness of the abilities of those they care for has much practical importance, especially from the safety standpoint.

Objectives: To determine whether the caregivers of persons with memory impairment or Alzheimer's disease know if their persons are able to recall their own drugs and medical histories.

Method: Persons with prodromal or probable AD (persons with AD) and their caregivers who were visiting our medical school's neurology and internal medicine clinics for routine follow-up care were recruited on the days of their appointments.

Femoral vascular conductance and peroneal muscle sympathetic nerve activity responses to acute epidural spinal cord stimulation in humans.

New Findings: What is the central question of this research? Does acute spinal cord stimulation increase vascular conductance and decrease muscle sympathetic nerve activity in the lower limbs of humans? What is the main finding and its importance? Acute spinal cord stimulation led to a rapid rise in femoral vascular conductance, and peroneal muscle sympathetic nerve activity demonstrated a delayed reduction that was not associated with the initial increase in femoral vascular conductance. These findings suggest that neural mechanisms in addition to attenuated muscle sympathetic nerve activity might be involved in the initial increase in femoral vascular conductance during acute spinal cord stimulation.

Abstract: Clinical cases have indicated an increase in peripheral blood flow after continuous epidural spinal cord stimulation (SCS) and that reduced muscle sympathetic nerve activity (MSNA) might be a potential mechanism.

John C. Vangilder (1935-2007): Neurosurgical Leader and Founder of the Department of Neurosurgery at the University of Iowa.

John C. VanGilder, the former professor and chairman of neurosurgery at The University of Iowa died on August 27, 2007 after making a lasting impact to the field of neurosurgery both in the United States and abroad. In this manuscript, we review VanGilder's life and achievements.

Spinal dura mater: biophysical characteristics relevant to medical device development.

Understanding the relevant biophysical properties of the spinal dura mater is essential to the design of medical devices that will directly interact with this membrane or influence the contents of the intradural space. We searched the literature and reviewed the pertinent characteristics for the design, construction, testing, and imaging of novel devices intended to perforate, integrate, adhere or reside within or outside of the spinal dura mater. The spinal dura mater is a thin tubular membrane composed of collagen and elastin fibres that varies in circumference along its length.