Low-Intensity MR-Guided Focused Ultrasound Mediated Disruption of the Blood-Brain Barrier for Intracranial Metastatic Diseases

Low-intensity MR-guided focused ultrasound in combination with intravenously injected microbubbles is a promising platform for drug delivery to the central nervous system past the blood-brain barrier. The blood-brain barrier is a key bottleneck for cancer therapeutics via limited inter- and intracellular transport. Further, drugs that cross the blood-brain barrier when delivered in a spatially nonspecific way, result in adverse effects on normal brain tissue, or at high concentrations, result in increasing risks to peripheral organs. As such, various anti-cancer drugs that have been developed or to be developed in the future would benefit from a noninvasive, temporary, and repeatable method of targeted opening of the blood-brain barrier to treat metastatic brain diseases. MR-guided focused ultrasound is a potential solution to these design requirements. The safety, feasibility and preliminary efficacy of MRgFUS aided delivery have been demonstrated in various animal models. In this review, we discuss this preclinical evidence, mechanisms of focused ultrasound mediated blood-brain barrier opening, and translational efforts to neuro-oncology patients

ADC, D, f dataset calculated through the simplified IVIM model, with MGMT promoter methylation, age, and ECOG, in 38 patients with wildtype IDH glioblastoma

Patients undergoing standard chemoradiation post-resection had MRIs at radiation planning and fractions 10 and 20 of chemoradiation. MRIs were 1.5T and 3D T2-FLAIR, pre- and post-contrast 3D T1-weighted (T1) and echo planar DWI with three b-values (0, 500, and 1000s/mm2) were acquired. T2-FLAIR was coregistered to T1C images. Non-overlapping T1 contrast-enhancing (T1C) and nonenhancing T2-FLAIR hyperintense regions were segmented, with necrotic/cystic regions, the surgical cavity, and large vessels excluded. The simplified IVIM model was used to calculate voxelwise diffusion coefficient (D) and perfusion fraction (f) maps; ADC was calculated using the natural logarithm of b = 1000 over b = 0 images. T1C and T2-FLAIR segmentations were brought into this space, and medians calculated. MGMT promoter methylation status (MGMTPMS), age at diagnosis, and Eastern Cooperative Oncology Group (ECOG) performance status were extracted from electronic medical records. The data were presented, analyzed, and described in the article, "Intravoxel incoherent motion (IVIM) modeling of diffusion MRI during chemoradiation predicts therapeutic response in IDH wildtype Glioblastoma", published in Radiotherapy and Oncology [1]

The attitudes of brain cancer patients and their caregivers towards death and dying: a qualitative study

<p>Abstract</p> <p>Background</p> <p>Much money and energy has been spent on the study of the molecular biology of malignant brain tumours. However, little attention has been paid to the wishes of patients afflicted with these incurable tumours, and how this might influence treatment considerations.</p> <p>Methods</p> <p>We interviewed 29 individuals – 7 patients dying of a malignant brain tumor and 22 loved ones. One-on-one interviews were conducted according to a pre-designed interview guide. A combination of open-ended questions, as well as clinical scenarios was presented to participants in order to understand what is meaningful and valuable to them when determining treatment options and management approaches. The results were analyzed, coded, and interpreted using qualitative analytic techniques in order to arrive at several common overarching themes.</p> <p>Results</p> <p>Seven major themes were identified. In general, respondents were united in viewing brain cancer as unique amongst malignancies, due in large part to the premium placed on mental competence and cognitive functioning. Importantly, participants found their experiences, however difficult, led to the discovery of inner strength and resilience. Responses were usually framed within an interpersonal context, and participants were generally grateful for the opportunity to speak about their experiences. Attitudes towards religion, spirituality, and euthanasia were also probed.</p> <p>Conclusion</p> <p>Several important themes underlie the experiences of brain cancer patients and their caregivers. It is important to consider these when managing these patients and to respect not only their autonomy but also the complex interpersonal toll that a malignant diagnosis can have.</p

Short and long term outcome of bilateral pallidal stimulation in chorea-acanthocytosis

BACKGROUND: Chorea-acanthocytosis (ChAc) is a neuroacanthocytosis syndrome presenting with severe movement disorders poorly responsive to drug therapy. Case reports suggest that bilateral deep brain stimulation (DBS) of the ventro-postero-lateral internal globus pallidus (GPi) may benefit these patients. To explore this issue, the present multicentre (n=12) retrospective study collected the short and long term outcome of 15 patients who underwent DBS. METHODS: Data were collected in a standardized way 2-6 months preoperatively, 1-5 months (early) and 6 months or more (late) after surgery at the last follow-up visit (mean follow-up: 29.5 months). RESULTS: Motor severity, assessed by the Unified Huntington's Disease Rating Scale-Motor Score, UHDRS-MS), was significantly reduced at both early and late post-surgery time points (mean improvement 54.3% and 44.1%, respectively). Functional capacity (UHDRS-Functional Capacity Score) was also significantly improved at both post-surgery time points (mean 75.5% and 73.3%, respectively), whereas incapacity (UHDRS-Independence Score) improvement reached significance at early post-surgery only (mean 37.3%). Long term significant improvement of motor symptom severity (≥ 20 % from baseline) was observed in 61.5 % of the patients. Chorea and dystonia improved, whereas effects on dysarthria and swallowing were variable. Parkinsonism did not improve. Linear regression analysis showed that preoperative motor severity predicted motor improvement at both post-surgery time points. The most serious adverse event was device infection and cerebral abscess, and one patient died suddenly of unclear cause, 4 years after surgery. CONCLUSION: This study shows that bilateral DBS of the GPi effectively reduces the severity of drug-resistant hyperkinetic movement disorders such as present in ChAc

Subcallosal Cingulate Deep Brain Stimulation for Treatment-refractory Anorexia Nervosa: Safety, Clinical Outcomes and Neuroimaging Correlates

Anorexia Nervosa (AN) has the highest mortality rate of any psychiatric condition, and despite its recognition for centuries, remains a significant treatment challenge. Marked by firmly entrenched maladaptive beliefs about body, weight and food, as well as high rates of psychiatric comorbidity, AN is a chronic illness in a large proportion of patients. The neural substrates of AN are now beginning to emerge, and appear to be related to dysfunctional, primarily limbic, circuits driving pathological thoughts and behaviours. Deep Brain Stimulation (DBS) is a neurosurgical procedure where implanted electrodes are used to regulate activity in critical nodes comprising such aberrant circuits. The promise of DBS in motor-circuit conditions, such as Parkinson’s Disease, has driven it’s investigation in other circuit-based disorders, including some psychiatric conditions. Converging evidence from clinical and imaging literatures suggests that AN is in large part a disorder of emotional processing, wherein disordered mood, anxiety, and affective dysregulation contribute to disease maintenance and are obstacles to effective treatment. The subcallosal cingulate (SCC), a key medial frontal structure involved in affective processing, has further been directly implicated in AN relevant pathways. As such, this work had three broad objectives: i) to establish the safety and initial efficacy of SCC DBS in a group of chronic and highly-refractory AN patients; ii) to show that SCC DBS can have network wide cerebral metabolic influence, on AN-relevant circuits and structures; and, iii) to investigate whether structural brain features, including hippocampal volume changes, are correlated with clinical outcomes of DBS. Our results showed that DBS is safe in AN, and associated in some patients with significant improvements in mood, anxiety and, over time, weight and treatment-response. Imaging results further showed DBS to be associated with substantial changes in glucose utilization in disease-relevant circuits, with preliminary evidence supporting a relationship between hippocampal volume changes and clinical improvements. In the context of highly refractory disease, these promising results suggest that DBS can inform AN circuit models, and be explored as a novel therapeutic option for treatment-resistant patients.Ph

Focused ultrasound opening of the blood-brain barrier for treatment of Parkinson\u27s disease

The expanding landscape of options for Parkinson\u27s disease (PD) therapeutics calls for novel ways to improve delivery of treatments to counteract neurodegeneration or enhance symptomatic control. This unmet need is particularly relevant for opportunities in gene therapy, which, in recent PD clinical trials, has required invasive neurosurgical approaches into the CNS. One of the promising techniques to bring new therapies into the brain for PD therapeutics involves an evolving technology, focused ultrasound. Focused ultrasound has been used to alleviate tremor by thermal ablation with high-energy sonication. Using similar equipment but much lower sonication energy, focused ultrasound assisted with micro-bubbles can temporarily open the blood-brain barrier at specific brain targets to facilitate real-time magnetic resonance-guided delivery of therapeutic agents. To explore the current status and future of focused ultrasound in transvascular therapeutics for PD, a November 2018 workshop reviewed its accomplishments and challenges. This report summarizes key points of discussion and provides further background to the promising roles focused ultrasound offers. © 2019 International Parkinson and Movement Disorder Society