Donald Whiting

Peripheral nerve stimulation for the treatment of occipital neuralgia and transformed migraine using a c1-2-3 subcutaneous paddle style electrode: a technical report.

In this article we will discuss the treatment of Occipital Neuralgia (ON) and Transformed Migraine (TM) using a paddle style surgical stimulator lead. A paddle style electrode may have advantages to the cylindrical style in reducing migrations from cervical tension or anchor dislodgement. It should be considered in refractory “neuropathic” cervicocranial syndromes such as ON and TM before moving on to more aggressive surgical interventions.

Hardware-Related Complications after Placement of Thalamic Deep Brain Stimulator Systems

Deep brain stimulation (DBS) has become a common therapeutic approach to patients with movement disorders. We evaluated results from two centers in a large metropolitan area where DBS systems are implanted into the thalamus for patients with tremor. Although all implanted systems led to an improvement in tremor, morbidity related to the hardware system occurred. A total of 23 hardware problems were noted in 66 patients undergoing implantation of 66 DBS systems (27% of patients). The most common problem included breakage of the electrode lead in its extracranial location, system infection, battery or connector problems, lead migration, and hemorrhage. Management was tailored to the specific hardware-related problem. Modifications in both surgical technique and hardware design should reduce the incidence of complications. Surgeons who place DBS systems should be aware of the spectrum of problems that can be associated with the device and its placement.

A survey of ventriculostomy and intracranial pressure monitor placement practices.

BACKGROUND Over the past 3 decades, the incidence of ICP monitoring has consistently increased and the indications for placement have expanded. Although ventriculostomy and ICP monitor placement are among the most commonly performed neurosurgical procedures, few studies have examined the current practice patterns of these procedures. METHODS A 10-question survey was sent to 3100 practicing neurosurgeons and a similar 11-question survey to 720 neurosurgery residents. Basic demographic information and estimated rates of proper ventriculostomy placement were sought. RESULTS Nine hundred thirty-four practicing neurosurgeons and 100 neurosurgery residents responded to our survey. Respondents estimated a mean of 1.4 passes per ventriculostomy procedure for practicing neurosurgeons, 1.4 for senior residents, and 2.4 for junior residents. Estimated rate of successful cannulation of the ipsilateral ventricle ranged from 72% to 84% for these groups. CONCLUSIONS This survey gives a sketch of the current state of practice and the attitudes of practitioners toward the placement procedure. Both residents and practicing neurosurgeons admit to frequently using multiple passes and frequent catheter placement outside the ipsilateral frontal horn. Despite these imperfections, survey respondents were reluctant to embrace technology that could improve placement accuracy if it increased procedure time. Intracranial pressure monitor placement is an ideal topic for prospective study. The prevalence of the procedure would allow the morbidity associated with various monitors and emerging technologies to be quickly and accurately established. Results of such study could be applied to the tens of thousands of patients undergoing these procedures annually.

Infections and Hardware Salvage after Deep Brain Stimulation Surgery: A Single-Center Study and Review of the Literature

Aims: Infection of hardware is a serious complication after deep brain stimulation (DBS), as this may result in additional surgery, cost and loss of treatment benefit for the patient. We report the incidence and management of infections after DBS in a single institution over the past 11 years. Methods: A database of 270 patients with 484 implants was used in the study. Incidence, clinical characteristics and management of infections were analyzed. Results: The overall infection rate was 9.3% (25/270) by patients and 6.8% (33/484) by episode/implants. The median time of infection after implantation was 64 days. Only 7/33 episodes (21.2%) occurred within 30 days after surgery, 22/33 episodes (66.7%) within 6 months and 28/33 episodes (84.8%) within 12 months. There was no age difference between infected and noninfected patients, while comorbidities were more frequent in the former. Infection rates before and after January 2003 were 14.3 and 4.9%, respectively. The rate of complete and partial hardware salvage was 30.3 and 21.2% while that of complete hardware removal was 48.5%. Patients with deep purulent infections and patients with Staphylococcus aureus as the causative organism were more likely to have their hardware removed. Conclusions: The incidence of hardware infections declined significantly over time. Improvements in hardware and implantation techniques may be responsible. Hardware can often be completely or partly saved in infected patients.

The history of external ventricular drainage

External ventricular drainage (EVD) is one of the most commonly performed neurosurgical procedures. It was first performed as early as 1744 by Claude-Nicholas Le Cat. Since then, there have been numerous changes in technique, materials used, indications for the procedure, and safety. The history of EVD is best appreciated in 4 eras of progress: development of the technique (1850-1908), technological advancements (1927-1950), expansion of indications (1960-1995), and accuracy, training, and infection control (1995-present). While EVD was first attempted in the 18th century, it was not until 1890 that the first thorough report of EVD technique and outcomes was published by William Williams Keen. He was followed by H. Tillmanns, who described the technique that would be used for many years. Following this, many improvements were made to the EVD apparatus itself, including the addition of manometry by Adson and Lillie in 1927, and continued experimentation in cannulation/drainage materials. Technological advancements allowed a great expansion of indications for EVD, sparked by Nils Lundberg, who published a thorough analysis of the use of intracranial pressure (ICP) monitoring in patients with brain tumors in 1960. This led to the application of EVD and ICP monitoring in subarachnoid hemorrhage, Reye syndrome, and traumatic brain injury. Recent research in EVD has focused on improving the overall safety of the procedure, which has included the development of guidance-based systems, virtual reality simulators for trainees, and antibiotic-impregnated catheters.

An International Survey of Deep Brain Stimulation Procedural Steps

Background: Deep brain stimulation (DBS) surgery is standard of care for the treatment of certain movement disorders. Objective: We sought to characterize the spectrum of steps performed in DBS surgery, at centers around the world where this surgery is performed. Methods: We identified the main steps in DBS surgery workflow and grouped these 19 steps into 3 phases (preoperative, operative, and postoperative). A survey tool, informed by a pilot survey, was administered internationally by trained study personnel at high- and low-volume DBS centers. Procedural components, duration, and surgeon motivational factors were assessed. Cluster analysis was used to identify procedural and behavioral clusters. Results: One hundred eighty-five procedure workflow surveys (143 DBS centers) and 65 online surveys of surgeon motivational drivers were completed (45% response rate). Significant heterogeneity in technique, operative time, and surgeon motivational drivers was reported across centers. Conclusions: We provide a description of the procedural steps involved in DBS surgery and the duration of these steps, based on an international survey. These data will enable individual surgeons and centers to examine their own experience relative to colleagues at other centers and in other countries. Such information could also be useful in comparing efficiencies and identifying workflow obstacles between different hospital environments.

Expanding applications of deep brain stimulation: a potential therapeutic role in obesity and addiction management

BackgroundThe indications for deep brain stimulation (DBS) are expanding, and the feasibility and efficacy of this surgical procedure in various neurologic and neuropsychiatric disorders continue to be tested. This review attempts to provide background and rationale for applying this therapeutic option to obesity and addiction. We review neural targets currently under clinical investigation for DBS—the hypothalamus and nucleus accumbens—in conditions such as cluster headache and obsessive-compulsive disorder. These brain regions have also been strongly implicated in obesity and addiction. These disorders are frequently refractory, with very high rates of weight regain or relapse, respectively, despite the best available treatments.MethodsWe performed a structured literature review of the animal studies of DBS, which revealed attenuation of food intake, increased metabolism, or decreased drug seeking. We also review the available radiologic evidence in humans, implicating the hypothalamus and nucleus in obesity and addiction.ResultsThe available evidence of the promise of DBS in these conditions combined with significant medical need, support pursuing pilot studies and clinical trials of DBS in order to decrease the risk of dietary and drug relapse.ConclusionsWell-designed pilot studies and clinical trials enrolling carefully selected patients with obesity or addiction should be initiated.

Surgical Complications of Deep Brain Stimulation

Background/Aims: Deep brain stimulation is a commonly performed procedure for intractable movement disorders. In this report we analyze the complications of a single surgeon at one institution over a 10-year period. Methods: A total of 191 patients received 330 electrode implants. Data was collected prospectively and analyzed retrospectively for the type and rate of complications. Results: The mean follow-up was 58.5 months. The overall surgical complication rate was 17.8% (59 complications in 330 implantations). These 59 complications involved 53 of 191 patients. The overall incidence of minor wound problems (hardware not removed), major wound problems (hardware removed) and hardware-related problems was 4.2% each, based on the total number of systems implanted. In addition 2.1% of the patients suffered minor bleeds while 1.6% had bleeds large enough to cause neurological deficits. The same percentage of patients (1.6%) either failed to benefit from the procedure or suffered complications unrelated to the procedure. A further 4/191 (2.1%) patients had neurological deficits without obvious hemorrhage on postoperative nonenhanced computerized tomography. Analysis of our complications from year to year shows a declining complication rate related to accumulated experience and better hardware design. Conclusion: Surgeon experience and hardware improvements have significantly reduced complications over time.

Deep brain stimulation for obesity—from theoretical foundations to designing the first human pilot study

Obesity is perhaps an evolutionary consequence of a species reared with intermittent caloric reward. Humans are hardwired to enjoy food, and our bodies voraciously extract and store energy from food as if each meal was the last. As an amalgam of behavioral and metabolic disturbance, obesity is an attractive target for deep brain stimulation (DBS) since neuromodulation may be able to influence both eating behavior and metabolism. The current pandemic proportions of obesity combined with the failures and morbidity of modern treatments remain the impetus behind the application of DBS to this complex disease. We review the rationale and scientific foundations for obesity DBS and explain how this preclinical evidence has helped sculpt the design of the first human pilot study.

Mapping of microstimulation evoked responses and unit activity patterns in the lateral hypothalamic area recorded in awake humans. Technical note.

Major contributions to the understanding of human brain function have come from detailed clinical reports of responses evoked by electrical stimulation and specific brain regions during neurosurgical procedures in awake humans. In this study, microstimulation evoked responses and extracellular unit recordings were obtained intraoperatively in 3 awake patients undergoing bilateral implantation of deep brain stimulation electrodes in the lateral hypothalamus. The microstimulation evoked responses exhibited a clear anatomical distribution. Anxiety was most reliably evoked by stimulation directed ventromedially within or adjacent to the ventromedial nucleus of the hypothalamus, nausea was most reliably evoked by stimulation directed at the center of the lateral hypothalamus, and paresthesias were most reliably evoked by stimulation at the border of the lateral hypothalamus and basal nuclei. Regarding the unit recordings, the firing rates of individual neurons did not have an anatomical distribution, but a small subpopulation of neurons located at the border of the lateral hypothalamus and basal nuclei exhibited a fast rhythmically bursting behavior with an intraburst frequency of 200-400 Hz and an interburst frequency of 10-20 Hz. Based on animal studies, the lateral hypothalamic area and surrounding hypothalamic nuclei are putatively involved with a variety of physiological, behavioral, and sensory functions. The lateral hypothalamus is situated to play a dynamic and complex role in human behavior and this report further shows that to be true. In addition, this report should serve as a valuable resource for future intracranial work in which accurate targeting within this region is required.