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With an aging population and increasing utilization of both cochlear implants (CI) to treat hearing loss and deep brain stimulation (DBS) to treat neurodegenerative movement disorders, more patients will be sequentially implanted with the two devices. As such, understanding both presurgical evaluations and surgical procedures will be of great importance to the treating cochlear implant surgeon and neurosurgeon in optimizing outcomes for both conditions. Two illustrative cases of sequential CI followed by DBS are reviewed. Relevant pre-, intra-, and postoperative issues are discussed for both DBS following CI surgery and CI following DBS surgery. Despite the potential for challenges, sequential CI and DBS (and vice versa) can provide substantial benefit to those individuals with severe hearing loss and movement disorders. A thorough understanding of both devices is critical to ensuring optimal outcomes. [ABSTRACT FROM AUTHOR]

Transcranial magnetic stimulation (TMS) is a non-invasive treatment protocol for treating several psychiatric conditions, including depression, migraine, smoking cessation, and obsessive-compulsive disorder. Past research suggests that TMS treatment outcomes vary based on neuroanatomy, functional connectivity, and tractography-based structural connectivity. In a previous study, 26 mild to moderate traumatic brain injury (mTBI) patients underwent repetitive transcranial magnetic stimulation (rTMS) and showed improvements in depression, post-concussive symptoms, and sleep dysfunction. The present study was a secondary analysis of that data. Anatomically accurate head models were derived from magnetic resonance imaging (MRI), and finite element analysis simulations were performed to mimic empirical data collection. This allowed for examination of the roles that age, brain scalp distance (BSD), gray matter volume (GMV), site-specific electrical field strength (EFS), and depolarized gray matter volume (DGMV) had on resting motor threshold (RMT) at the precentral gyrus (PreCG). We also investigated how EFS simulated at the dorsolateral prefrontal cortex (DLPFC) and RMT influenced rTMS treatment outcomes. Linear regression showed BSD was associated with EFS, RMT, and DGMV supporting efforts to derive accurate parameters from MRI-based modeling. Furthermore, linear mixed effects modeling showed RMT was associated with EFS and DGMV at the PreCG when age and individual neuroanatomy was accounted for suggesting MRI based anatomy and simulated EFS potentially determine TMS dosage. We did not observe any significant relationship between any of the measures from this study on empirically collected rTMS outcomes in mTBI suggesting further investigations into the mechanisms behind these outcomes are needed. [ABSTRACT FROM AUTHOR]

A randomized controlled trial was conducted to compare the effectiveness of bilateral deep brain stimulation with that of best medical therapy as a form of treatment for patients with advanced Parkinson disease. Results indicated that deep brain stimulation was more effective than best medical therapy, although associated with an increased risk of harmful events.

While repetitive transcranial magnetic stimulation (rTMS) has shown efficacy for cognitive difficulties accompanying depression, it is unknown if it can improve cognition in persons with traumatic brain injury. Using a sham-controlled crossover design, we tested the capacity of high frequency rTMS of the prefrontal cortex to improve neuropsychological performance in attention, learning and memory, and executive function. Twenty-six participants with cognitive complaints and a history of mild-to-moderate traumatic brain injury were randomly assigned to receive first either active or sham 10 Hz stimulation for 20 minutes (1200 pulses) per session for five consecutive days. After a one-week washout, the other condition (active or sham) was applied. Pre- and post-treatment measures included neuropsychological tests, cognitive and emotional symptoms, and EEG. Results indicated no effect of treatment on cognitive function. Subjective measures of depression, sleep dysfunction, post-concussive symptoms (PCS), and executive function showed significant improvement with stimulation, retaining improved levels at two-week follow-up. EEG delta power exhibited elevation one week after stimulation cessation. While there is no indication that rTMS is beneficial for neuropsychological performance, it may improve PCS and subjective cognitive dysfunction. Long-term alterations in cortical oscillations may underlie the therapeutic effects of rTMS. [ABSTRACT FROM AUTHOR]

Background: In this study, we describe a technique of optimizing the accuracy of frameless deep brain stimulation (DBS) lead placement through the use of a cannula poised at the entry to predict the location of the fully inserted device. This allows real-time correction of error prior to violation of the deep gray matter. Methods: We prospectively gathered data on radial error during the operative placements of 40 leads in 28 patients using frameless fiducial-less DBS surgery. Once the Nexframe had been aligned to target, a cannula was inserted through the center channel of the BenGun until it traversed the pial surface and a low-dose O-arm spin was obtained. Using 2 points along the length of the imaged cannula, a trajectory line was projected to target depth. If lead location could be improved, the cannula was inserted through an alternate track in the BenGun down to target depth. After intraoperative microelectrode recording and clinical assessment, another O-arm spin was obtained to compare the location of the inserted lead with the location predicted by the poised cannula. Results: The poised cannula projection and the actual implant had a mean radial discrepancy of 0.75 ± 0.64 mm. The poised cannula projection identified potentially clinically significant errors (avg 2.07 ± 0.73 mm) in 33% of cases, which were reduced to a radial error of 1.33 ± 0.66 mm (p = 0.02) after correction using an alternative BenGun track. The final target to implant error for all 40 leads was 1.20 ± 0.52 mm with only 2.5% of errors being >2.5 mm. Conclusion: The poised cannula technique results in a reduction of large errors (>2.5 mm), resulting in a decline in these errors to 2.5% of implants as compared to 17% in our previous publication using the fiducial-less method and 4% using fiducial-based methods of DBS lead placement. [ABSTRACT FROM AUTHOR]

Abstract: One in 3 patients with lumbar spinal stenosis undergoing decompressive laminectomy (DL) to alleviate neurogenic claudication do not experience substantial improvement. This prospective cohort study conducted in 193 Veterans aimed to identify key spinal and extraspinal factors that may contribute to a favorable DL outcome. Biopsychosocial factors evaluated pre-DL and 1 year post-DL were hip osteoarthritis, imaging-rated severity of spinal stenosis, scoliosis/kyphosis, leg length discrepancy, comorbidity, fibromyalgia, depression, anxiety, pain coping, social support, pain self-efficacy, sleep, opioid and nonopioid pain medications, smoking, and other substance use. The Brigham Spinal Stenosis (BSS) questionnaire was the main outcome. Brigham Spinal Stenosis scales (symptom severity, physical function [PF], and satisfaction [SAT]) were dichotomized as SAT < 2.42, symptom severity improvement ≥ 0.46, and PF improvement ≥ 0.42, and analyzed using logistic regression. Sixty-two percent improved in 2 of 3 BSS scales (ie, success). Baseline characteristics associated with an increased odds of success were-worse BSS PF (odds ratio [OR] 1.24 [1.08-1.42]), greater self-efficacy for PF (OR 1.30 [1.08-1.58]), lower self-efficacy for pain management (OR 0.80 [0.68-0.94]), less apparent leg length discrepancy (OR 0.71 [0.56-0.91]), greater self-reported alcohol problems (OR 1.53 [1.07-2.18]), greater treatment credibility (OR 1.31 [1.07-1.59]), and moderate or severe magnetic resonance imaging-identified central canal stenosis (OR 3.52 [1.06-11.6]) moderate, OR 5.76 [1.83-18.1] severe). Using opioids was associated with lower odds of significant functional improvement (OR 0.46 [0.23-0.93]). All P < 0.05. Key modifiable factors associated with DL success-self-efficacy, apparent leg length inequality, and opioids-require further investigation and evaluation of the impact of their treatment on DL outcomes. [ABSTRACT FROM AUTHOR]

Degenerative disease of the central nervous system is a growing public health concern. The primary role of neuroimaging in the workup of patients with probable or possible Alzheimer disease has typically been to exclude other significant intracranial abnormalities. In general, the imaging findings in structural studies, such as MRI, are nonspecific and have limited potential in differentiating different types of dementia. Advanced imaging methods are not routinely used in community or general practices for the diagnosis or differentiation of forms of dementia. Nonetheless, in patients who have been evaluated by a dementia expert, FDG-PET helps to distinguish Alzheimer disease from frontotemporal dementia. In patients with suspected dementia with Lewy bodies, functional imaging of the dopamine transporter (ioflupane) using SPECT may be helpful. In patients with suspected normal-pressure hydrocephalus, DTPA cisternography and HMPAO SPECT/CT brain may provide assessment. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment. [ABSTRACT FROM AUTHOR]

Patients with advanced Parkinson's disease (PD) often receive deep brain stimulation (DBS) treatment, in which conductive leads are surgically implanted in the brain. While DBS treats tremor and rigidity, patients often continue to suffer from speech and swallowing impairments. There is preliminary evidence that transcranial magnetic stimulation (TMS) of the cortex may be beneficial for these symptoms. However, the potential electromagnetic interactions of the strong magnetic fields from TMS on the conductive leads is unknown, and the combination therapy has not been approved for use. In this article, we report an experimental study of the safety of combining DBS and TMS. We fabricated an anatomically accurate head and brain phantom with electrical conductivities matching cerebrospinal fluid and averaged conductivity of gray and white matter. Induced current on an implanted DBS probe in the brain phantom was measured. Our results show that TMS will induce current values in the range or higher than typical DBS stimulation current. Thus, the combination of TMS/DBS treatment might cause over-stimulation in the brain when stimulated directly over the DBS lead with 100% TMS current intensity. [ABSTRACT FROM AUTHOR]

Introduction: Cortical cholinergic denervation resulting from degeneration of the nucleus basalis of Meynert (NBM) is a primary contributor to cognitive impairment and neuropsychiatric symptoms in the Lewy body diseases Parkinson's disease (PD), Parkinson's disease dementia (PDD), and dementia with Lewy bodies (DLB). Considering the morbidity associated with cognitive impairment and neuropsychiatric symptoms in these diseases, it is important to investigate all potential therapies to improve these symptoms. Areas covered: The authors review the current landscape of pharmacological and surgical therapies for mitigating the cortical cholinergic deficiency in PD, PDD, and DLB. Expert opinion: The cholinesterase inhibitors rivastigmine, donepezil, and galantamine are currently the primary pharmacological treatments available to improve cognition and associated neuropsychiatric symptoms in Lewy body diseases. Other possible pharmacological strategies include increasing acetylcholine release with 5-HT4 agonists or directly stimulating cholinergic receptors with muscarinic and nicotinic agonists. The side effect profile of muscarinic agonists is a deterrent to their future study, but 5-HT4 and nicotinic agonists deserve further investigation. Targeting the basal forebrain with either deep brain stimulation (DBS)- or cell-based therapies is another strategy to mitigate cortical cholinergic deficiency. Before NBM DBS studies continue, it will be important to resolve issues related to targeting, stimulation pattern, and duration. [ABSTRACT FROM AUTHOR]

Objective: Laser interstitial thermal therapy (LITT) for mesial temporal lobe epilepsy (mTLE) has reported seizure freedom rates between 36% and 78% with at least 1 year of follow‐up. Unfortunately, the lack of robust methods capable of incorporating the inherent variability of patient anatomy, the variability of the ablated volumes, and clinical outcomes have limited three‐dimensional quantitative analysis of surgical targeting and its impact on seizure outcomes. We therefore aimed to leverage a novel image‐based methodology for normalizing surgical therapies across a large multicenter cohort to quantify the effects of surgical targeting on seizure outcomes in LITT for mTLE. Methods: This multicenter, retrospective cohort study included 234 patients from 11 centers who underwent LITT for mTLE. To investigate therapy location, all ablation cavities were manually traced on postoperative magnetic resonance imaging (MRI), which were subsequently nonlinearly normalized to a common atlas space. The association of clinical variables and ablation location to seizure outcome was calculated using multivariate regression and Bayesian models, respectively. Results: Ablations including more anterior, medial, and inferior temporal lobe structures, which involved greater amygdalar volume, were more likely to be associated with Engel class I outcomes. At both 1 and 2 years after LITT, 58.0% achieved Engel I outcomes. A history of bilateral tonic‐clonic seizures decreased chances of Engel I outcome. Radiographic hippocampal sclerosis was not associated with seizure outcome. Significance: LITT is a viable treatment for mTLE in patients who have been properly evaluated at a comprehensive epilepsy center. Consideration of surgical factors is imperative to the complete assessment of LITT. Based on our model, ablations must prioritize the amygdala and also include the hippocampal head, parahippocampal gyrus, and rhinal cortices to maximize chances of seizure freedom. Extending the ablation posteriorly has diminishing returns. Further work is necessary to refine this analysis and define the minimal zone of ablation necessary for seizure control. [ABSTRACT FROM AUTHOR]

Background: Frameless stereotactic surgery utilizing fiducial-based (FB) registration is an established tool in the armamentarium of deep brain stimulation (DBS) surgeons. Fiducial-less (FL) registration via intraoperative CT, such as the O-arm, has been routinely used in spine surgery, but its accuracy for DBS surgery has not been studied in a clinical setting. Objective: We undertook a study to analyze the accuracy of the FL technique in DBS surgery and compare it to the FB method. Methods: In this prospective cohort study, 97 patients underwent DBS surgery using the NexFrame and the O-arm registration stereotactic system. Patients underwent FB (n = 50) registration from 2015 to 2016 and FL (n = 47) O-arm registration from 2016 to 2017. Results: The radial errors (RE) and vector/euclidean errors of FB and FL registration were not significantly different. There was no difference in additional passes between methods, but there was an increase in the number of RE ≥2.5 mm in the FL method. Conclusion: Although there was no statistically significant difference in RE or the need for additional passes, the increased number of errors ≥2.5 mm with the FL method (17 vs. 4% in FB) indicates the need for further study. We concluded that O-arm images of the implants should be utilized to assess and correct for this error. [ABSTRACT FROM AUTHOR]

Purpose: High-intensity training is recognised as a time-efficient way of improving aerobic fitness. However, there is a lack of consensus regarding the temporal nature of adaptation response and which peripheral and cardiac changes occur using the same exercise stimulus and protocol. Therefore, this study aimed to evaluate the progression of vascular and cardiac changes over a 6-week training period.Methods: Twelve healthy males (age 21 ± 2 years; 42.5 ± 8.3 ml min-1 kg-1) participated in a high-intensity training programme consisting of 1-min sprints, interspersed with 2 min active recovery, 3 days/week for 6 weeks on a cycle ergometer. Cardiac, vascular, blood lipids and VO2max measurements were taken at 0, 3 and 6 weeks and compared against a participant-matched control group (age 21 ± 2 years; 37.7 ± 8.3 ml min-1 kg-1).Results: There was a significant improvement in VO2max (42.5 ± 8.3-47.4 ± 8.5 ml min-1 kg-1; p = 0.009) in the training group and a significant decrease in systolic blood pressure (8%) from 0 to 6 weeks (p = 0.025). There was a small yet significant decrease in ejection fraction and increased end-systolic volume in both groups over time (p = 0.01) with no significant interaction effect (p > 0.05). A between-group difference in peak velocity of early diastolic mitral annular motion was also observed (p = 0.01). No improvements were seen in blood lipid profiles, central arterial stiffness and cardiometabolic risk score.Conclusions: Six weeks of high-intensity training increases aerobic fitness and is enough to stimulate initial reductions in peripheral pressure, but not sufficient to elicit structural and functional cardiac changes, reduce arterial stiffness or lower CV risk. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) of nucleus basalis of Meynert (NBM) is currently being evaluated as a potential therapy to improve memory and overall cognitive function in dementia. Although, the animal literature has demonstrated robust improvement in cognitive functions, phase 1 trial results in humans have not been as clear-cut. We hypothesize that this may reflect differences in electrode location within the NBM, type and timing of stimulation, and the lack of a biomarker for determining the stimulation’s effectiveness in real time. In this article, we propose a methodology to address these issues in an effort to effectively interface with this powerful cognitive nucleus for the treatment of dementia. Specifically, we propose the use of diffusion tensor imaging to identify the nucleus and its tracts, quantitative electroencephalography (QEEG) to identify the physiologic response to stimulation during programming, and investigation of stimulation parameters that incorporate the phase locking and cross frequency coupling of gamma and slower oscillations characteristic of the NBM’s innate physiology. We propose that modulating the baseline gamma burst stimulation frequency, specifically with a slower rhythm such as theta or delta will pose more effective coupling between NBM and different cortical regions involved in many learning processes. [ABSTRACT FROM AUTHOR]

Introduction: Bereavement is one of the most common and stressful life experiences one can endure. Typical grief reactions follow a course of recovery in which individuals come to terms with the loss and resume functioning within weeks to months. However, for some, grief remains indefinitely distressing. Complicated Grief (CG) refers to significant chronic impairment that stems from bereavement. Military service members experience myriad factors that likely increase their risk for developing CG. Such factors include unique bonds between service members, exposure to constant and extreme levels of stress, multiple losses, separation from family and loved ones, witnessing/learning about sudden violent and traumatic deaths, and handling human remains. The aim of this project was to explore the practicality and efficiency of screening for CG within a busy military mental health clinic, and also explore relationships between contextual variables related to a death that might be associated with screening positive for CG.Materials and Methods: As part of a clinical needs assessment, patients from a single mental health clinic at Naval Medical Center San Diego completed a brief grief survey that asked if they experienced a death of a person close to them, collected metrics related to losses they have experienced and included validated screeners for CG (The Brief Grief Questionnaire [BGQ] and the Inventory for Complicated Grief [ICG]). No data concerning gender, age, marital status, socioeconomic status, diagnosis, or purpose of visit (i.e., initial or follow-up visit) were collected. Institutional review board approval was obtained.Results: In our sample of service members presenting to an adult outpatient military mental health clinic, 43.5% reported having experienced a loss that still impacts them. Of that group, 61.7% screened positive on the BGQ, 59.2% screened positive on the ICG using a cutoff of 25, and 46.1% screened positive on the ICG using the cutoff of 30. These findings suggest that military service members seeking mental health treatment who endorsed experiencing a loss are at high risk for experiencing persisting, impairing grief. Additionally, patients who either lost a fellow service member and/or experienced loss while on deployment reported significantly higher scores on the BGQ or ICG than if they did not report those factors. Furthermore, correlations between total number of losses and ICG scores suggest that service members who experienced multiple losses may be more susceptible to CG symptoms.Conclusion: The findings from this preliminary investigation suggest that many service members receiving care in military mental health care are experiencing grief-related symptoms and distress, and a brief screen for grief can help capture many of those with grief related impairment. Research shows that CG needs to be directly targeted to treat its symptoms and associated impairment. We recommend that military mental health clinics consider adding some type of grief screener to their standard intake as well as making providers aware of the importance of monitoring potential grief reactions in their patients. [ABSTRACT FROM AUTHOR]

Leprosy is a chronic infectious, granulomatous disease caused by the intracellular bacillus Mycobacterium leprae that infects macrophages and Schwann cells. While relatively rare in the USA, there is about 200 new cases of leprosy every year with the majority occurring in the southern parts of the country. It is believed to be linked to the region of the nine-banned armadillo in patients with no significant travel history outside of the country. In this case report, we encountered a 58-year-old Central Florida man that had extensive exposure to armadillos and presented with the typical symptoms of large erythaematous patches, numbness and peripheral nerve hypertrophy. Once diagnosed properly, patients are then reported to the National Hansen’s Centre who provides the multidrug therapy for 12–24 months. Due to its rarity and its ability to mimic other more common ailments, leprosy should be included in the differential diagnosis in patients that have significant exposure to armadillos, live in the southern part of the country or have recently travelled to countries that have a high prevalence of leprosy. [ABSTRACT FROM AUTHOR]