Neuro-oncology application of next-generation, optically tracked robotic stereotaxis with intraoperative computed tomography: a pilot experience.

Objective: Innovations in robotics continue to reshape the landscape of neurosurgery. Here, the authors evaluated the safety and efficacy of the ExcelsiusGPS robot in the treatment of neuro-oncological, intracranial lesions.

Methods: The authors conducted a retrospective analysis of 19 consecutive adult patients with a neuro-oncological diagnosis who underwent intracranial biopsy and/or laser interstitial thermal therapy (LITT) with the assistance of the ExcelsiusGPS robot and intraoperative CT.

Robot-assisted, CT-guided placement of responsive neurostimulator system with bilateral centromedian thalamus depth electrodes for multifocal intractable epilepsy.

The responsive neurostimulator system has become increasingly popular in the surgical management of refractory epilepsy, with targeting of various thalamic nuclei showing promising results in select patients. A 42-year-old female presented for evaluation of refractory epilepsy consisting of generalized tonic-clonic and focal seizures with preserved awareness. Phase I and II monitoring suggested multifocal bilateral epilepsy with bilateral frontal onset, and the patient underwent robot-guided bilateral centromedian thalamic placement of the RNS System.

Exploring the Role of the Pulvinar Nucleus of the Thalamus in Occipital Lobe Epilepsy: A Case Report.

Understanding the role of the pulvinar nucleus may be critical for guiding circuit-targeted neurosurgical intervention in some patients. In this report, a 33-year-old female presented with focal onset occipital epilepsy with secondary generalization and with a previously radiated arteriovenous malformation within the right primary visual cortex. Phase II monitoring demonstrated the pulvinar nucleus was not involved in subclinical seizures restricted to the primary visual cortex, but it did become involved in clinical events with more extensive seizure spread into higher visual cortical regions.

Al-Zahrawi (936-1013 AD): On the Surgical Treatment of Neurological Disorders by the Father of Operative Surgery.

Background: Medical knowledge during the medieval ages flourished under the influence of great scholars of the Islamic Golden age such as Ibn Sina (Latinized as Avicenna), Abu Bakr al-Razi (Rhazes), and Abu al-Qasim Khalaf ibn al-Abbas al-Zahrawi, known as Albucasis. Much has been written on al-Zahrawi's innovation in various disciplines of medicine and surgery. In this article, we focus for on the contributions of al-Zahrawi toward the treatment of neurological disorders in the surgical chapters of his medical encyclopedia, Kitab al-Tasrif (The Method of Medicine).

Multi-timescale reinforcement learning in the brain.

To thrive in complex environments, animals and artificial agents must learn to act adaptively to maximize fitness and rewards. Such adaptive behavior can be learned through reinforcement learning, a class of algorithms that has been successful at training artificial agents and at characterizing the firing of dopamine neurons in the midbrain. In classical reinforcement learning, agents discount future rewards exponentially according to a single time scale, controlled by the discount factor.

Physician Practice Pattern Variations in Common Clinical Scenarios Within 5 US Metropolitan Areas.

Importance: While variations in quality of care have been described between US regions, physician-level practice pattern variations within regions remain poorly understood, notably among specialists.

Objective: To examine within-area physician-level variations in decision-making in common clinical scenarios where guidelines specifying appropriateness or quality of care exist.

Design Setting And Participants: This cross-sectional study used 2016 through 2019 data from a large nationwide network of commercial insurers, provided by Health Intelligence Company, LLC, within 5 metropolitan statistical areas (MSAs).

Intraoperative thalamocortical tract monitoring via direct cortical recordings during craniotomy.

Objective: Neuromonitoring of primary motor regions allows preservation of motor strength and is frequently employed during cranial procedures. Less is known about protection of sensory function and ability to modulate movements, both of which rely on integrity of thalamocortical afferents (TCA) to fronto-parietal regions. We describe our experience with TCA monitoring and their cortical relays during brain tumor surgery.

A Unified Framework for Dopamine Signals across Timescales.

Rapid phasic activity of midbrain dopamine neurons is thought to signal reward prediction errors (RPEs), resembling temporal difference errors used in machine learning. However, recent studies describing slowly increasing dopamine signals have instead proposed that they represent state values and arise independent from somatic spiking activity. Here we developed experimental paradigms using virtual reality that disambiguate RPEs from values.

Tremor Mimicking Ventricular Tachycardia on Telemetry.

A 79-year-old man with coronary artery disease and tremor-predominant Parkinson's disease underwent a gross total resection of a high-grade glioma and exhibited what appeared to be polymorphic ventricular tachycardia lasting 15-20 seconds on postoperative day 1. Further evaluation revealed that the patient did not have ventricular tachycardia, and that his abnormal telemetry signals were instead an artifact of his Parkinson's tremor. This case underscores the importance of considering tremor artifact when evaluating abnormal telemetry and electrocardiogram signals in patients with tremor, and highlights some features that can distinguish tremor artifact from a true arrhythmia.

Evolution of Osteocrin as an activity-regulated factor in the primate brain.

Sensory stimuli drive the maturation and function of the mammalian nervous system in part through the activation of gene expression networks that regulate synapse development and plasticity. These networks have primarily been studied in mice, and it is not known whether there are species- or clade-specific activity-regulated genes that control features of brain development and function. Here we use transcriptional profiling of human fetal brain cultures to identify an activity-dependent secreted factor, Osteocrin (OSTN), that is induced by membrane depolarization of human but not mouse neurons.

MEF2D drives photoreceptor development through a genome-wide competition for tissue-specific enhancers.

Organismal development requires the precise coordination of genetic programs to regulate cell fate and function. MEF2 transcription factors (TFs) play essential roles in this process but how these broadly expressed factors contribute to the generation of specific cell types during development is poorly understood. Here we show that despite being expressed in virtually all mammalian tissues, in the retina MEF2D binds to retina-specific enhancers and controls photoreceptor cell development.

Neurogenic Stress Cardiomyopathy After Aneurysmal Subarachnoid Hemorrhage.

Background: Neurogenic stress cardiomyopathy (NSC) is a known complication of aneurysmal subarachnoid hemorrhage (SAH). Detailed analyses of risk factors for its occurrence across large cohorts are relatively sparse.

Methods: A consecutive group of 300 patients with aneurysmal SAH was reviewed for the presence of markers of myocardial injury, including electrocardiogram changes (long QT, T-wave inversion), elevated plasma troponin levels (≥0.

Genome-wide identification and characterization of functional neuronal activity-dependent enhancers.

Experience-dependent gene transcription is required for nervous system development and function. However, the DNA regulatory elements that control this program of gene expression are not well defined. Here we characterize the enhancers that function across the genome to mediate activity-dependent transcription in mouse cortical neurons.

Isolated cerebral mucormycosis of the basal ganglia.

Isolated cerebral mucormycosis is a rare fungal infection for which morbidity and mortality remain high despite prompt tissue diagnosis and antifungal treatment. Intravenous drug use is strongly associated with this condition. However, other risk factors classically associated with systemic mucormycosis, such as poorly controlled diabetes and an immunocompromised state, are seldom seen in cases of isolated cerebral involvement.

Using whole-exome sequencing to identify inherited causes of autism.

Despite significant heritability of autism spectrum disorders (ASDs), their extreme genetic heterogeneity has proven challenging for gene discovery. Studies of primarily simplex families have implicated de novo copy number changes and point mutations, but are not optimally designed to identify inherited risk alleles. We apply whole-exome sequencing (WES) to ASD families enriched for inherited causes due to consanguinity and find familial ASD associated with biallelic mutations in disease genes (AMT, PEX7, SYNE1, VPS13B, PAH, and POMGNT1).

A chemical genetic approach reveals distinct EphB signaling mechanisms during brain development.

EphB receptor tyrosine kinases control multiple steps in nervous system development. However, it remains unclear whether EphBs regulate these different developmental processes directly or indirectly. In addition, given that EphBs signal through multiple mechanisms, it has been challenging to define which signaling functions of EphBs regulate particular developmental events.

CHMP1A encodes an essential regulator of BMI1-INK4A in cerebellar development.

Charged multivesicular body protein 1A (CHMP1A; also known as chromatin-modifying protein 1A) is a member of the ESCRT-III (endosomal sorting complex required for transport-III) complex but is also suggested to localize to the nuclear matrix and regulate chromatin structure. Here, we show that loss-of-function mutations in human CHMP1A cause reduced cerebellar size (pontocerebellar hypoplasia) and reduced cerebral cortical size (microcephaly). CHMP1A-mutant cells show impaired proliferation, with increased expression of INK4A, a negative regulator of stem cell proliferation.

Activity-dependent regulation of inhibitory synapse development by Npas4.

Neuronal activity regulates the development and maturation of excitatory and inhibitory synapses in the mammalian brain. Several recent studies have identified signalling networks within neurons that control excitatory synapse development. However, less is known about the molecular mechanisms that regulate the activity-dependent development of GABA (gamma-aminobutyric acid)-releasing inhibitory synapses.

Variable cytocompatibility of six cell lines with photoinitiators used for polymerizing hydrogels and cell encapsulation.

The development of biocompatible photopolymerizing polymers for biomedical and tissue engineering applications has the potential to reduce the invasiveness and cost of biomaterial implants designed to repair or augment tissues. However, more information is needed about the cellular toxicity of the compounds and initiators used in these systems. The current study evaluates the cellular toxicity of three ultraviolet sensitive photoinitiators on six different cell populations that are used for engineering numerous tissues.