Leonardo A. Frizon

Patients with advanced Parkinson’s disease often suffer from severe gait and balance problems, impacting quality of live and persisting despite optimization of standard therapies. The aim of this review was to systematically review the efficacy of STN-DBS programming techniques in alleviating gait disturbances in patients with advanced PD. Searches were conducted in PubMed, Embase, and Lilacs databases, covering studies published until May 2024. The review identified 36 articles that explored five distinct STN-DBS techniques aimed at addressing gait and postural instability in Parkinson’s patients: low-frequency stimulation, ventral STN stimulation for simultaneous substantia nigra activation, interleaving, asymmetric stimulation and a short pulse width study. Among these, 21 articles were included in the meta-analysis, which revealed significant heterogeneity among studies. Notably, low-frequency STN-DBS demonstrated positive outcomes in total UPDRS-III score and FOG-Q, especially when combined with dopaminergic therapy. The most favorable results were found for low-frequency STN stimulation. The descriptive analysis suggests that unconventional stimulation approaches may be viable for gait problems in patients who do not respond to standard therapies.

Drug-resistant epilepsy secondary to central nervous system tumors is generally caused by low grade gliomas^4,5,6,7,8,9. This group of tumors is usually found in brain eloquent areas, such as the insular lobe, rolandic cortex and supplementary motor area⁶. Performing surgery on patients with this condition has potential not only to treat drug-resistant epilepsy^7,10 but also to improve overall survival^{7,11,12,13,14}. However, operating on tumors in the so-called eloquent areas carries a significant risk of postoperative deficits. Refined surgical techniques, based on microneurosurgical anatomy^15,16,17 and brain mapping, have permitted safe resection with minimal risk^{18,19,20,21,22}.

Introduction: Translating basic science research into a safe and effective therapy for spinal cord injury (SCI) requires suitable large animal models for testing both implantable devices and biologic approaches to better approximate human anatomy and function. Hemisection lesions, routinely used for investigational purposes in small animals, are less frequently described in large animals that might be appropriate for translational studies. Size constraints of small animals (mice and rats) limits the predictability of the findings when scaled up. Our goal is to review the status of hemisection SCI in large animals across species and time to prepare for the testing of a novel intradural spinal cord stimulation device for control of spasticity in an ovine model. Methods and Results: We surveyed the literature on hemisection in quadrupeds and nonhuman primates, and catalogued the species, protocols and outcomes of the experimental work in this field. Feline, lapine, canine, simian, porcine, ovine and bovine models were the primary focal points. There is a consistent body of literature reporting use of the hemisection approach in large animals, but with differences in surgical technique depending on the goals and nature of the individual studies. While the injuries are not always consistent, the experimental variability is generally lower than that of the contusion-based approach. In general, as the body size of the animal increases, animal care requirements and the associated costs follow. In most cases, this is inversely correlated with the number of animals used in hemisection models. Conclusions: The hemisection approach to modeling SCI is straightforward compared with other methods such as the contusive impact and enables the transection of isolated ascending and descending tracts and segment specific cell bodies. This has certain advantages in models investigating post-injury axonal regrowth. However, this approach is not generally in line with the patho-physiologies encountered in SCI patients. Even so, the ability to achieve more control over the level of injury makes it a useful adjunct to contusive and ischemic approaches, and suggests a useful role in future translational studies.

BACKGROUND: There is a growing attention to determine the factors that predict quality of life (QoL) improvement after deep brain stimulation (DBS) for Parkinson's disease. Prior literature has largely focused on examining predictors one at a time, sometimes controlling for covariates. OBJECTIVE: To develop a model that could be used as a nomogram to predict improvement in QoL following DBS surgery in patients with Parkinson's disease. METHODS: All patients with complete pre- and postoperative movement disorder and neuropsychological testing who underwent DBS at a single institution between 2007-2012 were analyzed. The Parkinson's Disease Questionnaire-39 (PDQ-39) was used to measure QoL. Potential predictive factors, including patient demographics, clinical presentation characteristics, radiographic imaging, and motor and psychological testing were analyzed for impact on QoL. RESULTS: Sixty-seven patients were identified, 36 (53.73%) of whom had meaningfully improved QoL following surgery. Five baseline variables showed significant relationships with the outcome: years since symptom onset, percent change in on/off motor evaluation, levodopa equivalent daily dose, bilateral vs unilateral DBS implantation, and PDQ-39 score. The final model includes PDQ-39, percent change in UPRS-III, and years since symptom onset and is able to predict improvement in QoL with 81% accuracy. CONCLUSION: Our model accurately predicted whether QoL would improve in patients undergoing subthalamic nucleus DBS 81% of the time. Our data may serve as the foundation to further refine a clinically relevant prognostic tool that would assist the decision-making process for clinicians and DBS multidisciplinary teams assessing patient candidacy for surgery.

Background: Intrathecal baclofen (ITB) therapy is an effective way to manage spasticity in numerous conditions, including multiple sclerosis, stroke, and cerebral palsy. While pump failure is a common complication of ITB, improvements in device design have led to reduction of complications. In particular, the Ascenda catheter from Medtronic, Inc. was designed to resist kinking and associated complications; indeed, no incidences of catheter twisting or occlusion have been reported in literature prior to this case. Case Report: We report a case of a 32-year old gentleman who presented to the clinic with symptoms of baclofen withdrawal 19 months after he had a programmable pump implanted for spasticity. During the diagnostic evaluation it was discovered that the patients pump had flipped in his abdominal pocket. He was taken to surgery to reorient the pump, during which time it was noted the catheter was tightly coiled on itself occluding flow. The twisted catheter was excised and replaced with a new segment.His symptoms subsequently resolved. Conclusions: Although catheter occlusions have subsided since the approval of the Ascenda catheter, pump twiddler’s syndrome remains a risk factor for this complication. This is the first report describing this syndrome in a patient with the Ascenda catheter. Keywords: Ascenda Catheter; Intrathecal Baclofen Therapy (ITB); Baclofen, Twiddler’s Syndrome