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Primary central nervous system (CNS) diffuse large B-cell lymphoma with MYC and BCL2 rearrangements is a very rare lymphoma subtype. Deep brain stimulation is an effective minimally invasive therapeutic option for the treatment of refractory movement disorders, as well as some psychiatric disorders and chronic pain syndromes. Herein, we report a case of CNS lymphoma, which developed around an electrode of a deep brain stimulation (DBS) device. A 70-year-old woman with drug-resistant essential tremor was treated with bilateral thalamic DBS with significant symptomatic improvement over the following year. She presented to the emergency department with recurrent tremor, blurred vision, and confusion. Imaging showed a 4 cm heterogeneously enhancing centered around the DBS electrode. Pathologic evaluation and systemic workup confirmed a diagnosis of primary CNS diffuse large B-cell lymphoma. MYC and BCL2 rearrangements were identified. To our knowledge, this is the first reported case of a CNS lymphoma associated with a DBS electrode., Competing Interests: Declarations. Ethical approval and consent to participate: The authors have fulfilled all ethical standards relevant to this manuscript. Written informed consent to publication was obtained from the patient’s next of kin. Conflict of interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The authors present a historical analysis of the first neurosurgical service in Texas. Initially established as a subdivision within the Department of Surgery in the early 1900s, this service eventually evolved into the Department of Neurosurgery at the University of Texas Medical Branch (UTMB). The pivotal contributions of individual chiefs of neurosurgery throughout the years are highlighted, emphasizing their roles in shaping the growth of the neurosurgery division. The challenges faced by the neurosurgical division are documented, with particular attention given to the impact of hurricanes on Galveston Island, Texas, which significantly disrupted hospital operations. Additionally, a detailed account of recent clinical and research expansions is presented, along with the future directions envisioned for the Department of Neurosurgery. This work offers a comprehensive historical narrative of the neurosurgical service at UTMB, chronicling its journey of growth and innovation, and underscoring its profound contributions to Galveston's healthcare services, extending its impact beyond the local community.

The patient presented with left-sided chemosis, exophthalmos, and progressive visual loss. Cerebral angiography ed a left orbital arteriovenous malformation and an associated hematoma, with the point of fistulation between the left ophthalmic artery and the anterior section of the inferior ophthalmic vein, with retrograde flow through the superior ophthalmic vein. Transvenous embolization through the anterior facial and angular veins was unsuccessful, with residual shunting. Stereotactic-guided direct venous puncture and Onyx embolization was subsequently performed in the hybrid operating room (OR) to cure the fistula. A subciliary incision allowed for retraction of the orbital contents, creating an optimal trajectory. An endonasal endoscopic approach was performed after the embolization to decompress the orbit. This procedure is shown in video 11-11 neurintsurg;16/4/429/V1F1V1Video 1 ., Competing Interests: Competing interests: PK discloses leadership or fiduciary role in other board, society, committee or advocacy group, paid or unpaid PK Journal of Neurointerventional Surgery (JNIS) member of the Editorial Board., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

A middle-aged patient presented with right-sided chemosis, exophthalmos, and progressive visual loss. Digital subtraction angiography revealed a type D carotid-cavernous fistula (CCF). Transarterial embolization through the internal maxillary artery was unsuccessful, and there was no venous access to the CCF. A robotic-guided direct transtemporal embolization of the CCF with Onyx was performed, resulting in successful fistula obliteration and symptom resolution. This is the first reported case of a robotic-guided direct transcranial CCF embolization. We include a technical video that demonstrates this procedure (Supplemental File 1)., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Astroblastoma is a rare neoplasm characterized as a circumscribed glial neoplasm most often arising in the frontoparietal cerebral hemispheres in older children., Observations: We report an intriguing case of an astroblastoma recurrence 21 years after gross-total resection and radiation. A 32-year-old right-handed female presented to the emergency department for a generalized tonic-clonic seizure. She had a history of bipolar disorder, intractable migraines, and prior seizures linked to an astroblastoma previously resected three times. Magnetic resonance imaging on the current visit showed growth of the recurrent lesion to a 3.8-cm maximal diameter. Left-sided awake craniotomy was performed to remove the tumor while using speech mapping and 5-aminolevulinic acid (5-ALA). Targeted next-generation sequencing of the tumor revealed in-frame MN1::BEND2 fusion transcripts., Lessons: We found that 5-ALA can be used in astroblastoma patients to assist in gross-total resection, which is important for long-term survival. Our astroblastoma case demonstrated classic astroblastoma morphology, with typical perivascular astroblastic rosettes, and was brightly fluorescent after 5-ALA administration.

Paracavernous dural arteriovenous fistulas (pdAVFs) are extremely rare and can mimic carotid cavernous fistulas (CCFs) in both clinical presentation and imaging characteristics. Access to the venous pouch often presents the greatest challenge in the treatment of pdAVFs. Here we present a novel access technique utilizing an endoscopic endonasal transsphenoidal approach, where we directly puncture the venous pouch under both stereotactic guidance and endoscopic visualization, thereby completely embolizing a pdAVF with no alternate access (video 1). neurintsurg;15/10/1055/V1F1V1Video 1Technical video demonstrates the complete embolization of a pdAVF using an endoscopic endonasal transsphenoidal approach., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Surgery has become integral in treating children with tuberous sclerosis complex (TSC)-related drug-resistant epilepsy (DRE)., Objective: To describe outcomes of a multimodal diagnostic and therapeutic approach comprising invasive intracranial monitoring and surgical treatment and compare the complementary techniques of open resection and magnetic resonance-guided laser interstitial thermal therapy., Methods: Clinical and radiographic data were prospectively collected for pediatric patients undergoing surgical evaluation for TSC-related DRE at our tertiary academic hospital. Seizure freedom, developmental improvement, and Engel class were compared., Results: Thirty-eight patients (20 females) underwent treatment in January 2016 to April 2019. Thirty-five underwent phase II invasive monitoring with intracranial electrodes: 24 stereoencephalography, 9 craniotomy for grid/electrode placement, and 2 grids + stereoencephalography. With the multimodal approach, 33/38 patients (87%) achieved >50% seizure freedom of the targeted seizure type after initial treatment; 6/9 requiring secondary treatment and 2/2 requiring a third treatment achieved >50% freedom. The median Engel class was II at last follow-up (1.65 years), and 55% of patients were Engel class I/II. The mean age was lower for children undergoing open resection (2.4 vs 4.9 years, P = .04). Rates of >50% reduction in seizures (86% open resection vs 88% laser interstitial thermal therapy) and developmental improvement (86% open resection vs 83% magnetic resonance-guided laser interstitial thermal therapy) were similar., Conclusion: This hybrid approach of using both open surgical and minimally invasive techniques is safe and effective in treating DRE secondary to TSC. Clinical trials focused on treatment method with longer follow-up are needed to determine the optimal candidates for each approach and compare the treatment modalities more effectively., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)

Background: Primary central nervous system lymphoma (PCNSL) is an aggressive and extranodal non-Hodgkin lymphoma limited to the neuroaxis. In immunocompetent individuals, PCNSL is more common in older adults and lacks the association with the Epstein-Barr virus found in individuals with AIDS-associated PCNSL. Because the clinical presentation and radiographic findings of PCNSL are highly variable, stereotactic brain biopsy is typically required for definitive diagnosis. High-dose methotrexate, in combination with other chemotherapeutic agents with or without whole brain radiation, is the mainstay of treatment., Case Description: A 70-year-old HIV-negative woman presented with confusion, acute flaccid left arm weakness, and left hand numbness. Head computed tomography without contrast demonstrated a 1 cm hyperdense round lesion in the suprasellar cistern that prompted further evaluation. Gadolinium-enhanced brain magnetic resonance imaging demonstrated enhancing lesions with heterogeneous signal intensity in the suprasellar, pineal, and right periatrial regions that did not explain the limb weakness and numbness. Serum and cerebrospinal fluid (CSF) studies were unrevealing, and a diagnosis of PCNSL was made following stereotactic biopsy. The patient's liver cirrhosis precluded chemotherapy, but treatment with whole-brain radiation was pursued., Conclusion: The myriad clinical presentations and insidious course of PCNSL contribute to diagnostic difficulties, delays in treatment, and poor outcomes. Stereotactic brain biopsy is the primary method of PCNSL diagnosis since malignant cells are typically not detected in CSF. PCNSL should be considered in the differential diagnosis when immunocompetent elderly patients present with multiple intracranial lesions, even in the presence of lower motor neuron findings., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Surgical Neurology International.)

Objective: Since the Accreditation Council for Graduate Medical Education (ACGME) implemented duty-hour restrictions in 2003, many residency programs have adopted a night float system to comply with time constraints. However, some surgical subspecialities have been concerned that use of a night float system deprives residents of operative experience. In this study, the authors describe their training program's transition to a night float system and its impact on resident operative experience., Methods: The authors conducted a single-program study of resident surgical case volume before and after implementing the night float system at 3 of their 5 hospitals from 2014 to 2020. The authors obtained surgical case numbers from the ACGME case log database., Results: Junior residents received a concentrated educational experience, whereas senior residents saw a significant decrease from 112 calls/year to 17. Logged cases significantly increased after implementation of the night float system (8846 vs 10,547, p = 0.04), whereas cases at non-night float hospitals remained the same. This increase was concurrent with an increase in hospital cases. This difference was mainly driven by senior resident cases (p = 0.010), as junior and chief residents did not show significant differences in logged cases (p > 0.40). Lead resident cases increased significantly after implementation of the night float system (6852 vs 8860, p = 0.04). When normalized for increased hospital cases, resident case increases were not statistically significant., Conclusions: Transitioning to a night float call system at the authors' institution increased overall resident operative cases, particularly for lead resident surgeons. Based on the results of this study, the authors recommend the use of a night float call system to consolidate night calls, which increases junior resident-level educational opportunities and senior resident cases.

Background: A number of stereotactic platforms are available for performing deep brain stimulation (DBS) lead implantation. Robot-assisted stereotaxy has emerged more recently demonstrating comparable accuracy and shorter operating room times compared with conventional frame-based systems., Objective: To compare the accuracy of our streamlined robotic DBS workflow with data in the literature from frame-based and frameless systems., Methods: We retrospectively reviewed 126 consecutive DBS lead placement procedures using a robotic stereotactic platform. Indications included Parkinson disease (n = 94), essential tremor (n = 21), obsessive compulsive disorder (n = 7), and dystonia (n = 4). Procedures were performed using a stereotactic frame for fixation and the frame pins as skull fiducials for robot registration. We used intraoperative fluoroscopic computed tomography for registration and postplacement verification., Results: The mean radial error for the target point was 1.06 mm (SD: 0.55 mm, range 0.04-2.80 mm) on intraoperative fluoroscopic computed tomography. The mean operative time for an asleep, bilateral implant without implantable pulse generator placement was 238 minutes (SD: 52 minutes), and skin-to-skin procedure time was 116 minutes (SD: 42 minutes)., Conclusion: We describe a streamlined workflow for DBS lead placement using robot-assisted stereotaxy with a comparable accuracy profile. Obviating the need for checking and switching coordinates, as is standard for frame-based DBS, also reduces the chance for human error and facilitates training., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)

We present a parietal interhemispheric approach to resect a pineal region falcotentorial meningioma. Three-dimensional (3D) modeling was used to visualize and plan the surgical approach in virtual reality (Video 1). A 78-year-old woman was incidentally found to have a slow-growing falcotentorial meningioma. The tumor was first treated with stereotactic radiosurgery, but the patient had progressive confusion, memory issues, and bilateral temporal field cuts with interval expansion of the tumor and significantly increased peritumoral vasogenic edema on magnetic resonance imaging. After recommending tumor resection, the patient consented to surgery and underwent resection via a posterior interhemispheric subsplenial approach. Using a 3D model in virtual reality, we discuss the advantages and disadvantages of various classical approaches to the pineal region for resection of this tumor. 1-3 Falcotentorial meningiomas often displace the deep veins inferiorly, making an interhemispheric approach more favorable. 4-6 Preoperative visualization of critical deep venous structures with the 3D model was a valuable adjunct to magnetic resonance imaging for achieving safe resection. We depict key steps of the surgical planning process using virtual reality and demonstrate how simulation can be used to evaluate risks and benefits of different surgical corridors. A small rim of residual tumor adherent to the deep cerebral veins was intentionally left behind in order to minimize risk of morbidity to the patient. 7 At 1-month follow-up, the patient's cognition had returned to baseline and her vision had significantly improved. Ultimately, surgical planning using virtual reality promotes both neurosurgical education and patient safety through clear visualization and understanding of different surgical approaches., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Intracranial solitary fibrous tumors (ISFTs) are rare neoplasms of mesenchymal origin that originate from the meninges. ISFTs of the skull base can be challenging to treat, as resection can be complicated by skull base anatomy. We present 2 cases of ISFT, the first manifesting with compressive cranial neuropathy from Meckel cave involvement and the second a posterior fossa lesion causing symptomatic hydrocephalus., Methods: A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed database was queried with title/abstract keywords "intracranial," "solitary fibrous tumor," "hemangiopericytoma," "SFT," and "HPC." Search results were reviewed to exclude cases not involving the skull base. References from all selected articles were reviewed for potential additional cases. Patient demographic and clinical data from 58 identified skull base cases were collected for qualitative synthesis., Results: Visual disturbances were the most common presenting symptom (30 cases, 52%) followed by headache (22 cases, 38%). The most common site of involvement was the sellar/parasellar region (18 cases, 31%) followed by middle fossa/temporal bone (14 cases, 24%). Resection was performed in 55 cases; gross total resection was reported in 26 cases (45%) and subtotal resection was reported in 21 cases (36%). Tumor recurrence was documented in 15 cases (26%) with median and mean follow-up periods of 16 and 29.9 months, respectively., Conclusions: We discuss presentation, imaging, histopathology, and management considerations for ISFTs while highlighting the potentially complex nature of skull base lesions and need for multidisciplinary approach to treatment., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Spastic cerebral palsy is caused by an insult to the developing brain. Various medical and surgical procedures are used to reduce tone., Objective: To describe a novel method of magnetic resonance-guided laser interstitial thermal ablation for palliative rhizotomy., Methods: Patients treated at a single institution with percutaneous rhizotomy using magnetic resonance-guided laser interstitial thermal therapy were identified. Preoperative and postoperative Modified Ashworth Scale scores were collected as well as procedural information., Results: Two male children (7.8 and 19 yr, respectively) with spastic quadriparesis were treated using this technique. Neither patient experienced surgical or perioperative complications, and both were discharged from the hospital within 48 h. Each of them demonstrated improvement in his Modified Ashworth Scale score with no need for retreatment for spasticity at last follow-up., Conclusion: These 2 cases illustrate a novel technique for treating spasticity in the setting of cerebral palsy. Further study of this technique in additional patients, and comparison with traditional methods of surgical tone reduction, are warranted., (© Congress of Neurological Surgeons 2020.)

Emergent thrombectomy for large vessel occlusion is now a standard procedure within neurosurgery. In general, thrombectomy is attempted via a femoral artery puncture. However, due to anatomic variability and arterial tortuosity, target vessels cannot be catheterized in roughly 5% of patients.1 Radial artery access is an alternative to femoral artery access; however, target arteries for thrombectomy cannot be catheterized via the femoral or radial arteries in a small subset of patients. Direct carotid puncture is an alternative route of access for emergent thrombectomy in acute stroke.2,3 In this video, we present a patient with an acute right middle cerebral artery occlusion who was taken for emergent thrombectomy after consenting for the procedure. Because of unfavorable arterial anatomy, the right internal carotid artery could not be successfully catheterized via femoral or radial arterial punctures. We ultimately catheterized the right internal carotid artery and middle cerebral artery via a direct carotid puncture. We review the technique for direct carotid puncture, and discuss the outcomes associated with this method of access in the setting of acute large vessel occlusion. We also discuss complications associated with direct carotid puncture. Direct carotid puncture is an acceptable bail-out technique in the setting of emergent thrombectomy when femoral and/or radial access is not possible. Figure at 2:18 republished from Sekhar LN, Iwai Y, Wright DC, Bloom M. Vein graft replacement of the middle cerebral artery after unsuccessful embolectomy: case report. Neurosurgery. 1993;33(4):723-727, by permission of the Congress of Neurological Surgeons. Table at 6:05 modified from Roche A, Griffin E, Looby S, et al. Direct carotid puncture for endovascular thrombectomy in acute ischemic stroke. J NeuroIntervent Surg. 2019;11(7):647-652, ©The Authors, 2019, with permission from Dr Sarah Power. Table at 6:22 reproduced from Jadkhav AP, Ribo M, Grandhi R, et al. Transcervical access in acute ischemic stroke. J NeuroIntervent Surg. 2014:6(9):652-657, ©2013, with permission from the BMJ Publishing Group Ltd., (Copyright © 2021 by the Congress of Neurological Surgeons.)

Medically refractory pain in those with advanced cancer significantly reduces one's quality of life. Therefore, palliative interventions to mitigate cancer pain and reduce opioid requirements are necessary to reduce patient suffering and opioid-induced side effects. Hypophysectomy, a largely forgotten pain procedure with several technical variations, has been repeatedly studied in small series with encouraging results, though historically has been fraught with complications. As a result, the minimally invasive and more tolerable stereotactic radiosurgery (SRS) hypophysectomy has resurfaced as a possible treatment for cancer-related pain. While the mechanism of pain relief is not entirely understood, the hypothalamohypophyseal axis appears to play an essential role in pain perception and transmission and involves C fiber signal processing and downstream modulation of the brainstem and spinal cord via the hypothalamus. This review highlights the role of hypophysectomy in alleviating advanced cancer pain, both in hormonal and nonhormonal malignancy and the current mechanistic understanding of pain relief for the three primary hypophysectomy modalities used historically: surgical and chemical adenolysis, as well as the more recent, SRS hypophysectomy. Given the lack of high-quality evidence for stereotactic radiosurgery hypophysectomy, there is a need for further rigorous and prospective clinical studies despite its ideal and noninvasive approach., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Larkin, Karas, McGinnis, McCutcheon and Viswanathan.)

Background: Robotic stereotaxy is increasingly common in epilepsy surgery for the implantation of stereo-electroencephalography (sEEG) electrodes for intracranial seizure monitoring. The use of robots is also gaining popularity for permanent stereotactic lead implantation applications such as in deep brain stimulation and responsive neurostimulation (RNS) procedures. Objective: We describe the evolution of our robotic stereotactic implantation technique for placement of occipital-approach hippocampal RNS depth leads. Methods: We performed a retrospective review of 10 consecutive patients who underwent robotic RNS hippocampal depth electrode implantation. Accuracy of depth lead implantation was measured by registering intraoperative post-implantation fluoroscopic CT images and post-operative CT scans with the stereotactic plan to measure implantation accuracy. Seizure data were also collected from the RNS devices and analyzed to obtain initial seizure control outcome estimates. Results: Ten patients underwent occipital-approach hippocampal RNS depth electrode placement for medically refractory epilepsy. A total of 18 depth electrodes were included in the analysis. Six patients (10 electrodes) were implanted in the supine position, with mean target radial error of 1.9 ± 0.9 mm (mean ± SD). Four patients (8 electrodes) were implanted in the prone position, with mean radial error of 0.8 ± 0.3 mm. The radial error was significantly smaller when electrodes were implanted in the prone position compared to the supine position ( p = 0.002). Early results (median follow-up time 7.4 months) demonstrate mean seizure frequency reduction of 26% ( n = 8), with 37.5% achieving ≥50% reduction in seizure frequency as measured by RNS long episode counts. Conclusion: Prone positioning for robotic implantation of occipital-approach hippocampal RNS depth electrodes led to lower radial target error compared to supine positioning. The robotic platform offers a number of workflow advantages over traditional frame-based approaches, including parallel rather than serial operation in a bilateral case, decreased concern regarding human error in setting frame coordinates, and surgeon comfort., Competing Interests: SS is a consultant for Boston Scientific, Abbott, and Zimmer Biomet. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Karas, Giridharan, Treiber, Prablek, Khan, Shofty, Krishnan, Chu, Van Ness, Maheshwari, Haneef, Gavvala and Sheth.)

The classic presentation of a carotid-cavernous fistula (CCF) is unilateral painful proptosis, chemosis, and vision loss. Just as the goal of treatment for a dural arteriovenous fistula (dAVF) is obliteration of the entire fistulous connection and the proximal draining vein, the modern treatment of CCF is endovascular occlusion of the cavernous sinus via a transvenous or transarterial route. Here, the authors present the case of a woman with a paracavernous dAVF mimicking the clinical and radiographic presentation of a CCF. Without any endovascular route available to access the fistulous connection and venous drainage, the authors devised a novel direct hybrid approach by performing an endoscopic endonasal transsphenoidal direct puncture and Onyx embolization of the fistula.

Experimentalists studying multisensory integration compare neural responses to multisensory stimuli with responses to the component modalities presented in isolation. This procedure is problematic for multisensory speech perception since audiovisual speech and auditory-only speech are easily intelligible but visual-only speech is not. To overcome this confound, we developed intracranial encephalography (iEEG) deconvolution. Individual stimuli always contained both auditory and visual speech, but jittering the onset asynchrony between modalities allowed for the time course of the unisensory responses and the interaction between them to be independently estimated. We applied this procedure to electrodes implanted in human epilepsy patients (both male and female) over the posterior superior temporal gyrus (pSTG), a brain area known to be important for speech perception. iEEG deconvolution revealed sustained positive responses to visual-only speech and larger, phasic responses to auditory-only speech. Confirming results from scalp EEG, responses to audiovisual speech were weaker than responses to auditory-only speech, demonstrating a subadditive multisensory neural computation. Leveraging the spatial resolution of iEEG, we extended these results to show that subadditivity is most pronounced in more posterior aspects of the pSTG. Across electrodes, subadditivity correlated with visual responsiveness, supporting a model in which visual speech enhances the efficiency of auditory speech processing in pSTG. The ability to separate neural processes may make iEEG deconvolution useful for studying a variety of complex cognitive and perceptual tasks. SIGNIFICANCE STATEMENT Understanding speech is one of the most important human abilities. Speech perception uses information from both the auditory and visual modalities. It has been difficult to study neural responses to visual speech because visual-only speech is difficult or impossible to comprehend, unlike auditory-only and audiovisual speech. We used intracranial encephalography deconvolution to overcome this obstacle. We found that visual speech evokes a positive response in the human posterior superior temporal gyrus, enhancing the efficiency of auditory speech processing., (Copyright © 2020 Metzger et al.)

The superior frontal gyrus (SFG) is an important region implicated in a variety of tasks including motor movement, working memory, resting-state, and cognitive control. A detailed understanding of the subcortical white matter of the SFG could improve postoperative morbidity related to surgery around this gyrus. Through DSI-based fiber tractography validated by gross anatomical dissection, we characterized the fiber tracts of the SFG based on their relationships to other well-known neuroanatomic structures. Diffusion imaging from the Human Connectome Project from 10 healthy adult subjects was used for fiber tractography. We evaluated the SFG as a whole based on its connectivity with other regions. All tracts were mapped in both hemispheres, and a lateralization index was calculated based on resultant tract volumes. Ten cadaveric dissections were then performed using a modified Klingler technique to delineate the location of major tracts integrated within the SFG. We identified four major SFG connections: the frontal aslant tract connecting to the inferior frontal gyrus; the inferior fronto-occipital fasciculus connecting to the cuneus, lingual gyrus, and superior parietal lobule; the cingulum connecting to the precuneus and parahippocampal gyrus/uncus; and a callosal fiber bundle connecting the SFG bilaterally. The functional networks of the SFG involve a complex series of white matter tracts integrated within the gyrus, including the FAT, IFOF, cingulum, and callosal fibers. Postsurgical outcomes related to this region may be better understood in the context of the fiber-bundle anatomy highlighted in this study. Clin. Anat. 33:823-832, 2020. © 2019 Wiley Periodicals, Inc., (© 2019 Wiley Periodicals, Inc.)

Epilepsy affects many children worldwide, with drug-resistant epilepsy affecting 20-40% of all children with epilepsy. This carries a significant burden for patients and their families and is strongly correlated with poor cognitive outcomes, depression, anxiety, developmental delay, and impaired activities of daily living. For this reason, we sought to explore the role of pediatric epilepsy surgery and provide an overview of the factors contributing to epilepsy surgery planning and execution. We review the necessary preoperative evaluations, surgical indications, planning considerations, and surgical options to provide a clear pathway in the evaluation and planning of pediatric epilepsy surgery., Competing Interests: There are no conflicts of interest., (Copyright: © 2019 Surgical Neurology International.)

Mutations in the neurofibromin 2 ( NF2 ) gene were among the first genetic alterations implicated in meningioma tumorigenesis, based on analysis of neurofibromatosis type 2 (NF2) patients who not only develop vestibular schwannomas but later have a high incidence of meningiomas. The NF2 gene product, merlin, is a tumor suppressor that is thought to link the actin cytoskeleton with plasma membrane proteins and mediate contact-dependent inhibition of proliferation. However, the early recognition of the crucial role of NF2 mutations in the pathogenesis of the majority of meningiomas has not yet translated into useful clinical insights, due to the complexity of merlin's many interacting partners and signaling pathways. Next-generation sequencing studies and increasingly sophisticated NF2 -deletion-based in vitro and in vivo models have helped elucidate the consequences of merlin loss in meningioma pathogenesis. In this review, we seek to summarize recent findings and provide future directions toward potential therapeutics for this tumor.

Visual information about speech content from the talker's mouth is often available before auditory information from the talker's voice. Here we examined perceptual and neural responses to words with and without this visual head start. For both types of words, perception was enhanced by viewing the talker's face, but the enhancement was significantly greater for words with a head start. Neural responses were measured from electrodes implanted over auditory association cortex in the posterior superior temporal gyrus (pSTG) of epileptic patients. The presence of visual speech suppressed responses to auditory speech, more so for words with a visual head start. We suggest that the head start inhibits representations of incompatible auditory phonemes, increasing perceptual accuracy and decreasing total neural responses. Together with previous work showing visual cortex modulation (Ozker et al., 2018b) these results from pSTG demonstrate that multisensory interactions are a powerful modulator of activity throughout the speech perception network., Competing Interests: PK, JM, BM, LZ, KS, DY, MB No competing interests declared, (© 2019, Karas et al.)

Obsessive compulsive disorder (OCD) is a common, disabling psychiatric disease characterized by persistent, intrusive thoughts and ritualistic, repetitive behaviors. Deep brain stimulation (DBS) is thought to alleviate OCD symptoms by modulating underlying disturbances in normal cortico-striato-thalamo-cortical (CSTC) circuitry. Stimulation of the ventral portion of the anterior limb of the internal capsule (ALIC) and underlying ventral striatum ("ventral capsule/ventral striatum" or "VC/VS" target) received U.S. FDA approval in 2009 for patients with severe, treatment-refractory OCD. Over the decades, DBS surgical outcome studies have led to an evolution in the electrical stimulation target. In parallel, advancements in neuroimaging techniques have allowed investigators to better visualize and define CSTC circuits underlying the pathophysiology of OCD. A critical analysis of these new data suggests that the therapeutic mechanism of DBS for OCD likely involves neuromodulation of a widespread cortical/subcortical network, accessible by targeting fiber bundles in the ventral ALIC that connect broad network regions. Future studies will include advances in structural and functional imaging, analysis of physiological recordings, and utilization of next-generation DBS devices. These tools will enable patient-specific optimization of DBS therapy, which will hopefully further improve outcomes.

Tuberous sclerosis complex (TSC) is a neurocutaneous autosomal-dominant genetic syndrome marked by development of hamartomatous lesions arising from dysfunction of the mammalian target of rapamycin (mTOR) pathway. Although TSC remains a heterogeneous clinical entity, the recent inclusion of genetic diagnostic criteria reflects advancement in our understanding of its underlying etiopathogenesis. Abnormal cellular growth, differentiation, and migration result in multisystem sequelae, with neurologic manifestations of TSC representing the primary cause of morbidity and mortality for the majority of individuals. Modern imaging techniques aid in the diagnosis of TSC and guide treatment strategies by revealing central nervous system findings. Cortical tubers are the namesake lesion of the disorder and occur in up to 90% of cases, often exerting significant epileptogenic potential. Subependymal nodules are found in 80% of patients as calcified tumors lining the ependyma of the lateral ventricles. In some cases, these nodules are thought to progress to subependymal giant cell astrocytomas and may present with obstructive hydrocephalus. Retinal astrocytic hamartomas are also common, present in 50% of patients. Surgery remains the treatment of choice for large or symptomatic lesions, though clinical trials have highlighted a potential role for mTOR pathway antagonism. A multidisciplinary approach is necessary for achieving optimal patient outcomes., (© 2018 Wiley Periodicals, Inc.)

The authors present the first report of laser interstitial thermal therapy (LITT) ablation of a recurrent chordoma metastasis to the cervical spine. This patient was a 75-year-old woman who was diagnosed and treated for a sacral chordoma, and then developed metastases to the lung and upper thoracic spine. Unfortunately she experienced symptomatic recurrence at the C-7 spinous process. She underwent an uncomplicated LITT to the lesion. The patient convalesced without incident and was discharged on postoperative Day 1. She received stereotactic spinal radiosurgery to the lesion at a dose of 24 Gy in 1 fraction. At the 3-month follow-up evaluation she had radiographic response and improvement in her symptoms.

Background: Pseudoaneurysms of scalp arteries have been reported in rare cases after iatrogenic injury; however, they are far more commonly seen after traumatic injuries. They are usually associated with the superficial temporal artery; however, there have been a few reports of psuedoaneurysms of the occipital artery (OA)., Case Description: We present a unique case of an OA pseudoaneurysm presenting with delayed postoperative hemorrhage after a retrosigmoid craniotomy. The pseudoaneurysm was treated by coil embolization., Conclusions: The patient recovered fully after endovascular embolization. Other treatment options for pseudoaneurysms of facial, temporal, and scalp arteries include surgical clipping/trapping with excision, Hunterian ligation, or direct compression. Pseudoaneurysms of extracranial scalp arteries are rare and most often caused by traumatic compression of the artery against a bony ridge. Despite their rarity, pseudoaneurysms secondary to iatrogenic injury to extracranial arteries should be considered in the differential diagnosis in patients presenting with delayed incisional pain, redness, and swelling., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Primary intraosseous calvarial hemangiomas (PICHs) are generally rare and predominate (3:1) in women. Occurrence in the frontal and parietal bones is most common, but involvement of the occipital bone is exceedingly rare, representing 3 of 125 cases in a series of PICHs studied by Heckl et al. in 2000. Histopathology establishes the diagnosis of cavernous hemangioma, which represents the most common subtype of intraosseous hemangiomas. Others include sclerosing, cellular, and capillary. When they do occur in the calvarium, they are most often asymptomatic and discovered incidentally or due to a palpable defect in the skull., Case Description: In this case, a calvarial hemangioma was found to be the cause of elevated intracranial pressure in a 35-year-old woman. Resection of the hemangioma and reconstruction of the calvarium provided a complete cure for her symptoms., Conclusions: Primary intraosseous hemangiomas are rarely symptomatic but must be considered in the differential for calvarial lesions as part of safe surgical planning. Formulating an accurate differential diagnosis by acquiring proper imaging studies and specifically recognizing the classical "starburst" appearance, as well as considering the highly vascular pathology to avoid excess blood loss, is important. This unique case of a hemangioma-induced venous sinus compression and subsequent elevated intracranial pressure illustrates that hemangiomas can arise from any part of the calvarium and cause a wide variety of clinical symptoms., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background and Purpose: Level of consciousness is frequently assessed by command-following ability in the clinical setting. However, it is unclear what brain circuits are needed to follow commands. We sought to determine what networks differentiate command following from noncommand following patients after hemorrhagic stroke., Methods: Structural MRI, resting-state functional MRI, and electroencephalography were performed on 25 awake and unresponsive patients with acute intracerebral and subarachnoid hemorrhage. Structural injury was assessed via volumetric T1-weighted MRI analysis. Functional connectivity differences were analyzed against a template of standard resting-state networks. The default mode network (DMN) and the task-positive network were investigated using seed-based functional connectivity. Networks were interrogated by pairwise coherence of electroencephalograph leads in regions of interest defined by functional MRI., Results: Functional imaging of unresponsive patients identified significant differences in 6 of 16 standard resting-state networks. Significant voxels were found in premotor cortex, dorsal anterior cingulate gyrus, and supplementary motor area. Direct interrogation of the DMN and task-positive network revealed loss of connectivity between the DMN and the orbitofrontal cortex and new connections between the task-positive network and DMN. Coherence between electrodes corresponding to right executive network and visual networks was also decreased in unresponsive patients., Conclusions: Resting-state functional MRI and electroencephalography coherence data support a model in which multiple, chiefly frontal networks are required for command following. Loss of DMN anticorrelation with task-positive network may reflect a loss of inhibitory control of the DMN by motor-executive regions. Frontal networks should thus be a target for future investigations into the mechanism of responsiveness in the intensive care unit environment., (© 2014 American Heart Association, Inc.)

Deep brain stimulation (DBS), the practice of placing electrodes deep into the brain to stimulate subcortical structures with electrical current, has been increasing as a neurosurgical procedure over the past 15 years. Originally a treatment for essential tremor, DBS is now used and under investigation across a wide spectrum of neurological and psychiatric disorders. In addition to applying electrical stimulation for clinical symptomatic relief, the electrodes implanted can also be used to record local electrical activity in the brain, making DBS a useful research tool. Human single-neuron recordings and local field potentials are now often recorded intraoperatively as electrodes are implanted. Thus, the increasing scope of DBS clinical applications is being matched by an increase in investigational use, leading to a rapidly evolving understanding of cortical and subcortical neurocircuitry. In this review, the authors discuss recent innovations in the clinical use of DBS, both in approved indications as well as in indications under investigation. Deep brain stimulation as an investigational tool is also reviewed, paying special attention to evolving models of basal ganglia and cortical function in health and disease. Finally, the authors look to the future across several indications, highlighting gaps in knowledge and possible future directions of DBS treatment.