Publications by authors named "Jason A Chen"

Neuronal-glioma interactions are increasingly recognized as critical in the development and progression of central nervous system tumors. Recent research highlights that gliomas can integrate into neural circuits through various mechanisms, including the synaptogenic factor thrombospondin-1 (TSP-1). This new mechanistic understanding of cancer neuroscience allows for novel insights into target discovery.

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Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy has emerged as an effective treatment for tremor, particularly in those patients who are excluded from deep brain stimulation. The authors illustrate an example of MRgFUS thalamotomy, targeting the ventralis intermedius nucleus, in a 78-year-old patient with tremor who had features of essential tremor and tremor-predominant Parkinson's disease. Significant tremor improvement was seen during the procedure.

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The centromedian (CM) nucleus of the thalamus is a promising target for a range of brain diseases including drug-resistant generalized and multifocal epilepsy. CM is highly connected to cortical and subcortical regions including frontoparietal/sensorimotor cortex, striatum, brainstem, and cerebellum, which are involved in some generalized epilepsy syndromes like Lennox-Gastaut syndrome (LGS). In this video, the authors describe their methodology for targeting CM for deep brain stimulation (DBS).

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The emerging field of cancer neuroscience reshapes our understanding of the intricate relationship between the nervous system and cancer biology; this new paradigm is likely to fundamentally change and advance neuro-oncological care. The profound interplay between cancers and the nervous system is reciprocal: Cancer growth can be induced and regulated by the nervous system; conversely, tumors can themselves alter the nervous system. Such crosstalk between cancer cells and the nervous system is evident in both the peripheral and central nervous systems.

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Intrinsic, expansile pontine tumors typically occur in the pediatric population. These tumors characteristically present as diffuse intrinsic pontine glioma (DIPG), which is now considered as diffuse midline glioma (DMG), H3K27-mutated of the pons. DIPG has limited treatment options and a poor prognosis, and the value of tissue diagnosis from an invasive biopsy remains controversial.

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We treated a 20-year-old woman in Paraguay with a ruptured intraventricular Spetzler-Martin Grade 3 AVM, and illustrate microsurgical resection without embolization in this video.

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A 48-year-old male with progressive congestive myelopathy had a craniocvervical DAVF treated with surgical clipping using ICG to confirm solitary inflow.

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Cavernous venous malformations (CavVMs) account for a spectrum of lesions with a shared pathogenesis. Their anatomical location dictates their clinical features and surgical treatment. Extradural and dura-based CavVMs were discussed in Part 1 of this review.

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Cavernous-type malformations are venous lesions that occur in multiple locations throughout the body, and when present in the CNS, they have canonically been referred to as cavernomas, cavernous angiomas, and cerebral cavernous malformations. Herein all these lesions are referred to as "cavernous venous malformations" (CavVMs), which is congruent with the current International Society for the Study of Vascular Anomalies classification system. Even though histologically similar, depending on their location relative to the dura mater, these malformations can have different features.

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Purpose: Abnormalities in notochordal development can cause a range of developmental malformations, including the split notochord syndrome and split cord malformations. We describe two cases that appear related to unusual notochordal malformations, in a female and a male infant diagnosed in the early postnatal and prenatal periods, which were treated at our institution. These cases were unusual from prior cases given a shared constellation of an anterior cervicothoracic meningocele with a prominent "neural stalk," which coursed ventrally from the spinal cord into the thorax in proximity to a foregut duplication cyst.

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Lumbar facet fractures are rarely reported and have been linked to sports and spine surgery. We describe the case of a 77-year-old patient who sustained an injury from multiple landmine blasts during the Vietnam War. He had low back pain since that time, which was initially managed conservatively.

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Background: Herpes simplex virus (HSV) is a common cause of viral encephalitis and can result in refractory seizures. Although HSV encephalitis (HSVE) is treated primarily with acyclovir, surgery can play a role in medically intractable cases.

Objective: To systematically review cases describing surgery for the treatment of severe HSVE.

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World Health Organization (WHO) grade 4 gliomas of the cerebellum are rare entities whose understanding trails that of their supratentorial counterparts. Like supratentorial high-grade gliomas (sHGG), cerebellar high-grade gliomas (cHGG) preferentially affect males and prognosis is bleak; however, they are more common in a younger population. While current therapy for cerebellar and supratentorial HGG is the same, recent molecular analyses have identified features and subclasses of cerebellar tumors that may merit individualized targeting.

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Article Synopsis
  • - The case study presents a 74-year-old man with severe essential tremor and diffuse skull thickening (hyperostosis), who did not improve after undergoing magnetic resonance-guided focused ultrasound (MRgFUS) treatment.
  • - Pre-treatment imaging indicated a low skull density ratio (SDR) and the presence of tricortical hyperostosis, yet post-treatment MRI showed no changes or lesions.
  • - A literature review revealed that out of three similar cases of patients with hyperostosis, all also failed MRgFUS treatment, suggesting that tricortical hyperostosis may be a contraindication for this therapeutic approach.
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Background: Hypercoagulability with thrombosis and associated inflammation has been well-documented in COVID-19, and catastrophic cerebral venous sinus thromboses (CVSTs) have been described. Another COVID-19-related complication is bacterial superinfection, including sinusitis. Here, the authors reported three cases of COVID-19-associated sinusitis, meningitis, and CVST and summarized the literature about septic intracranial thrombotic events as a cause of headache and fever in COVID-19.

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Background: The Woven EndoBridge (WEB) device is designed for intrasaccular flow disruption for embolization of intracranial aneurysms. In limited experience so far, the rate of rupture after adequate occlusion by embolization has been low.

Methods: A 58-year-old man initially had an incidental, unruptured 10.

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Objectives: Moyamoya disease is an idiopathic cerebrovascular disorder in which patients experience recurrent transient ischemic attacks, ischemic or hemorrhagic strokes, headaches, and seizures from progressive stenosis of the vessels of the anterior circulation. The mainstay of treatment in symptomatic patients is surgical revascularization. Here, we present the case of a moyamoya patient in which a failed encephaloduroarteriosynangiosis, after new strokes, is recycled and converted into a combined "double barrel" direct superficial temporal artery to middle cerebral artery bypass with included video.

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Background: Intramedullary abscesses are rare infections of the spinal cord. Intramedullary abscesses often have a complex presentation, making a high index of suspicion essential for prompt diagnosis and management.

Case Presentation: We present two cases of intramedullary abscesses referred to and ultimately managed at our institution.

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Despite advances in surgical resection and chemoradiation, high-grade brain tumors continue to be associated with significant morbidity/mortality. Novel therapeutic strategies and approaches are, therefore, desperately needed for patients and their families. Given the success experienced in treating multiple other forms of cancer, immunotherapy and, in particular, immunovirotherapy are at the forefront amongst novel therapeutic strategies that are currently under investigation for incurable brain tumors.

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Background: Hyperplasia of the choroid plexus represents a rare cause of communicating hydrocephalus in children. Recent work has associated such disease with genetic abnormalities (such as perturbations in chromosome 9). Given such extensive cerebrospinal fluid (CSF) overproduction, patients with choroid plexus hyperplasia often fail CSF diversion and therefore require adjuvant interventions.

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Spinal extradural arachnoid cysts (SEACs) are uncommon spinal lesions that may cause myelopathy, most frequently in the 2nd decade of life. There are multiple theories of their pathogenesis, and associated entities include spinal trauma, spina bifida, and the lymphedema-distichiasis syndrome. The authors report the case of an otherwise healthy, developmentally normal 13-year-old boy who presented with multiple SEACs.

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Background: Lumbar puncture is a common procedure that can be safely performed in most patients. Certain populations may have increased risk for complications following lumbar puncture, but the significance of basilar invagination is often underappreciated.

Case Description: A 45-year-old woman with basilar invagination received multiple lumbar punctures in the workup of acute meningitis.

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The IPDGC (The International Parkinson Disease Genomics Consortium) and EADB (Alzheimer Disease European DNA biobank) are listed correctly as an author to the article, however, they were incorrectly listed more than once.

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Immunotherapy with oncolytic herpes simplex virus-1 therapy offers an innovative, targeted, less-toxic approach for treating brain tumors. However, a major obstacle in maximizing oncolytic virotherapy is a lack of comprehensive understanding of the underlying mechanisms that unfold in CNS tumors/associated microenvironments after infusion of virus. We demonstrate that our multiplex biomarker screening platform comprehensively informs changes in both topographical location and functional states of resident/infiltrating immune cells that play a role in neuropathology after treatment with HSV G207 in a pediatric Phase 1 patient.

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