A parcellation-based connectomic model of hemispatial neglect.

Background And Purpose: Hemispatial neglect is characterized by a reduced awareness to stimuli on the contralateral side. Current literature suggesting that damage to the right parietal lobe and attention networks may cause hemispatial neglect is conflicting and can be improved by investigating a connectomic model of the "neglect system" and the anatomical specificity of regions involved in it.

Methods: A meta-analysis of voxel-based morphometry magnetic resonance imaging (MRI) studies of hemispatial neglect was used to identify regions associated with neglect.

Primary Dural Repair Using Titanium Microclips Following Lateral Skull Base Surgery.

 Standard techniques for primary dural repair following lateral skull base surgery are both technically challenging and time consuming without the potential for primary dural repair. Inadequate closure may result in postoperative cerebrospinal fluid (CSF) leak infectious sequalae. Traditional methods of dural repair rely on secondary obliteration of the CSF fistula.

Parcellation-based tractographic modeling of the salience network through meta-analysis.

Background: The salience network (SN) is a transitory mediator between active and passive states of mind. Multiple cortical areas, including the opercular, insular, and cingulate cortices have been linked in this processing, though knowledge of network connectivity has been devoid of structural specificity.

Objective: The current study sought to create an anatomically specific connectivity model of the neural substrates involved in the salience network.

Practice Patterns of Ventriculoperitoneal Shunt Placement in Academic and Community Settings: A National Survey of Practicing Neurosurgeons.

Objective: We sought to assess the practice patterns of ventriculoperitoneal shunt (VPS) placement by neurosurgeons at academic, community, and government-based institutions.

Methods: Using the American Association of Neurological Surgeons directory, a total of 3673 practicing neurosurgeons were contacted. The survey received 495 responses (57% academic, 41% community, 3% other/government based).

A systematic review of amino acid PET in assessing treatment response to temozolomide in glioma.

The response assessment in neuro-oncology (RANO) criteria have been the gold standard for monitoring treatment response in glioblastoma (GBM) and differentiating tumor progression from pseudoprogression. While the RANO criteria have played a key role in detecting early tumor progression, their ability to identify pseudoprogression is limited by post-treatment damage to the blood-brain barrier (BBB), which often leads to contrast enhancement on MRI and correlates poorly to tumor status. Amino acid positron emission tomography (AA PET) is a rapidly growing imaging modality in neuro-oncology.

Resection and radiotherapy for intracranial ependymoma: a multiinstitutional 50-year experience.

Objective: Maximal safe resection is the standard-of-care treatment for adults with intracranial ependymoma. The value of adjuvant radiotherapy remains unclear as these tumors are rare and current data are limited to a few retrospective cohort studies. In this study, the authors assembled a cohort of patients across multiple international institutions to assess the utility of adjuvant radiotherapy in this patient population.

Congress of Neurological Surgeons systematic review and evidence-based guidelines update on the role of imaging in the management of progressive glioblastoma in adults.

Target Population: These recommendations apply to adults with glioblastoma who have been previously treated with first-line radiation or chemoradiotherapy and who are suspected of experiencing tumor progression.

Question: In patients with previously treated glioblastoma, is standard contrast-enhanced magnetic resonance imaging including diffusion weighted imaging useful for diagnosing tumor progression and differentiating progression from treatment-related changes?

Level Ii: Magnetic resonance imaging with and without gadolinium enhancement including diffusion weighted imaging is recommended as the imaging surveillance method to detect the progression of previously diagnosed glioblastoma.

Question: In patients with previously treated glioblastoma, does magnetic resonance spectroscopy add useful information for diagnosing tumor progression and differentiating progression from treatment-related changes beyond that derived from standard magnetic resonance imaging with and without gadolinium enhancement?

Level Ii: Magnetic resonance spectroscopy is recommended as a diagnostic method to differentiate true tumor progression from treatment-related imaging changes or pseudo-progression in patients with suspected progressive glioblastoma.

Patient Outcomes in Disorders of Consciousness Following Transcranial Magnetic Stimulation: A Systematic Review and Meta-Analysis of Individual Patient Data.

There are few treatments with limited efficacy for patients with disorders of consciousness (DoC), such as minimally conscious and persistent vegetative state (MCS and PVS). In this meta-analysis of individual patient data (IPD), we examine studies utilizing transcranial magnetic stimulation (TMS) as a treatment in DoC to determine patient and protocol-specific factors associated with improved outcomes. We conducted a systematic review of PubMed, Ovid Medline, and Clinicaltrials.

A systematic review of the utility of amino acid PET in assessing treatment response to bevacizumab in recurrent high-grade glioma.

Background: Currently, bevacizumab (BEV), an antiangiogenic agent, is used as an adjunctive therapy to re-irradiation and surgery in patients with recurrent high-grade gliomas (rHGG). BEV has shown to decrease enhancement on MRI, but it is often unclear if these changes are due to tumor response to BEV or treatment-induced changes in the blood brain barrier. Preliminary studies show that amino acid PET can aid in distinguishing these changes on MRI.

Dynamic Occlusion of Distal Ventriculoperitoneal Shunt Catheter after Infusion Port Placement: A New Shunt Malfunction.

Shunt failure requiring reintervention remains a common complication of hydrocephalus treatment. Here, we report a novel cause of mechanical shunt obstruction in an adult patient: position-dependent intermittent occlusion via an infusion port catheter. A 51-year-old woman with a grade II oligodendroglioma presented in a delayed fashion following surgery with a pseudomeningocele.

Cerebral venous thrombosis of the sphenoparietal sinus: A case report.

Background: Cerebral venous thrombosis (CVT) is a rare cause of stroke that preferentially affects reproductive aged females and patients with hereditary or acquired thrombotic risk factors. The superior sagittal sinus and transverse sinus are the two most common sites for thrombus formation.

Case Description: We report a case of CVT arising in a very rare location, the sphenoparietal sinus.

Prolactinoma extension as a contributing factor in dopamine agonist-induced CSF rhinorrhea: a systematic review of the literature.

Background: Dopamine agonist-induced cerebrospinal fluid (CSF) rhinorrhea is an uncommon treatment-related complication arising in 6.1% of prolactinoma patients treated with dopamine agonists. Locally invasive prolactinomas may create CSF fistulae through formation of dural and osseous skull base defects.

Parcellation-based anatomic model of the semantic network.

Introduction: The semantic network is an important mediator of language, enabling both speech production and the comprehension of multimodal stimuli. A major challenge in the field of neurosurgery is preventing semantic deficits. Multiple cortical areas have been linked to semantic processing, though knowledge of network connectivity has lacked anatomic specificity.

Parcellation-based modeling of the supplementary motor area.

Introduction: The supplementary motor area (SMA) plays an important role in the initiation and coordination of internally and externally cued movements. Such movements include reaching, grasping, speaking, and bilateral hand coordination. While many studies discuss the SMA and its relationship to other parts of the motor network, there is minimal literature examining the connectivity of the SMA outside of the motor network.

Parcellation-based anatomic modeling of the default mode network.

Background: The default mode network (DMN) is an important mediator of passive states of mind. Multiple cortical areas, such as the anterior cingulate cortex, posterior cingulate cortex, and lateral parietal lobe, have been linked in this processing, though knowledge of network connectivity had limited tractographic specificity.

Methods: Using resting-state fMRI studies related to the DMN, we generated an activation likelihood estimation (ALE).

Primary Repair of Posteriorly Located Anterior Skull Base Dural Defects Using Nonpenetrating Titanium Clips in Cranial Trauma.

 Primary repair of posteriorly located anterior skull base (ASB) dural defects following cranial trauma is made difficult by narrow operative corridors and adherent dura mater. Inadequate closure may result in continued cerebrospinal fluid (CSF) leak and infectious sequelae. Here, we report surgical outcomes following the use of nonpenetrating titanium microclips as an adjunctive repair technique in traumatic anterior skull base dural defects extending from the olfactory groove to the tuberculum sellae.

Rosette-forming glioneuronal tumor: an illustrative case and a systematic review.

Background: Rosette-forming glioneuronal tumors (RGNTs) are rare, low-grade, primary CNS tumors first described in 2002 by Komori et al. RGNTs were initially characterized as a World Health Organization (WHO) grade I tumors typically localized to the fourth ventricle. Although commonly associated with an indolent course, RGNTs have the potential for aggressive behavior.

Laser Interstitial Thermal Therapy Case Series: Choosing the Correct Number of Fibers Depending on Lesion Size.

Background: Laser interstitial thermal therapy (LITT) is being used for the treatment of recurrent glioblastoma multiforme (GBM). Lesions can be treated using 1 or multiple LITT fibers depending on the preference of surgeons. Usually, more fibers are needed for coverage of larger tumors.

Anatomy and White Matter Connections of the Inferior Temporal Gyrus.

Background: The inferior temporal gyrus (ITG) is known to be involved in high-cognitive functions, including visual and language comprehensions and emotion regulation. A detailed understanding of the nature of association fibers could significantly improve postoperative morbidity related to declining capacity. Through diffusion spectrum imaging-based fiber tracking, we have characterized these connections on the basis of their relationships to other cortical areas.

Anatomy and white matter connections of the fusiform gyrus.

The fusiform gyrus is understood to be involved in the processing of high-order visual information, particularly related to faces, bodies, and stimuli characterized by high spatial frequencies. A detailed understanding of the exact location and nature of associated white-tracts could significantly improve post-operative morbidity related to declining capacity. Through generalized q-sampling imaging (GQI) validated by gross dissection as a direct anatomical method of identifying white matter tracts, we have characterized these connections based on relationships to other well-known structures.

Natural history of intracranial meningiomas.

We know that the extent of resection is the greatest predictor of long-term survival. However, the potential tradeoff for gross total resection in difficult locations is diminished quality of life. Benign subtotally resected or small incidentally discovered meningiomas may be followed clinically especially in the elderly.

Parcellation-based modeling of the dorsal premotor area.

Background: The dorsal premotor area (DPM) plays an important role in hand coordination and muscle recruitment for lifting activities. Lesions in the area have demonstrated that the DPM is critical in the integration of movements that require combinations of reaching, grasping, and lifting. While many have looked at its functional connectivity, few studies have shown the full anatomical connectivity of DPM including its connections beyond the motor network.

Laser Interstitial Thermal Therapy for Metastatic Melanoma After Failed Radiation Therapy: A Case Series.

Background: Laser interstitial thermal therapy (LITT) is a growing technology to treat a variety of brain lesions. It offers an alternative to treatment options, such as open craniotomy and stereotactic radiosurgery.

Objective: To analyze our experience using LITT for metastatic melanoma.

Anatomy and white matter connections of the lateral occipital cortex.

Purpose: White matter tracts link different regions of the brain, and the known functions of those interconnected regions may offer clues about the roles that white matter tracts play in information relay. The authors of this report discuss the structure and function of the lateral occipital lobe and how the lateral occipital lobe communicates with other regions via white matter tracts.

Methods: The authors used generalized q-sampling imaging and cadaveric brain dissections to uncover the subcortical white matter connections of the lateral occipital lobe.