Cervical Diastematomyelia: A Case Presentation and Systematic Review.

Diastematomyelia is a rare congenital disorder characterized by the separation of the spinal cord by an osseocartilaginous or fibrous septum. While diastematomyelia has been reported to be more common in the thoracic and lumbar regions, the true incidence of cervical diastematomyelia is currently unknown. In this study, we conducted the most comprehensive systematic review to date of all other case reports of diastematomyelia to better characterize the incidence of cervical diastematomyelia and provide comprehensive statistics on the clinical characteristics of diastematomyelia generally. Ninety-one articles were included in our study, which comprised 252 males (27.9%) and 651 females (72.0%) (and one patient with unspecified gender). In 507 cases, the vertebral level of the diastematomyelia was described, and we recorded those levels as either cervical ( n = 8, 1.6%), thoracic ( n = 220, 43.4%), lumbar ( n = 277, 54.6%), or sacral ( n = 2, 0.4%). In 719 cases, the type of diastematomyelia was specified as either Type I ( n = 482, 67.0%) or Type II ( n = 237, 33.0%). Our study found that diastematomyelia has been reported in the cervical region in only 1.6% of cases, and we provide comprehensive data that this disorder occurs in female-to-male ratio of approximately 2.6:1 and Type I versus Type II diastematomyelia in an estimated ratio of 2:1.

Gross Total Resection of a Ruptured Micro-arteriovenous Malformation within the Cerebellar Peduncle: A Case Report and Qualitative Review of the Literature.

Deep-seated micro-arteriovenous malformations (micro-AVMs) may pose a challenge for complete yet safe resection. We propose the strategic placement of two to three microaneurysm clips throughout the hemorrhage cavity to successfully localize the micro-AVM nidus via digital subtraction angiography (DSA). We successfully demonstrate this novel method in a 15-year-old adolescent boy with cerebellar intraparenchymal hemorrhage who underwent hematoma evacuation and expansile duraplasty. He was found to have a 1-cm nidus of a micro-AVM with early venous drainage located in the right middle cerebellar peduncle. Five days later, we proceeded to resect the micro-AVM; however, a clear nidus or bleeding source was unable to be localized intraoperatively despite the use of stereotactic neuronavigation. In turn, we placed two mini-aneurysm clips superiorly and inferiorly within the hematoma cavity, which led to successful localization via DSA and complete resection. No surgical complications occurred. The patient completely recovered from right-sided weakness and dysarthria 6 to 12 months postoperatively. Our technique allows for the rapid localization and complete resection of micro-AVM nidi when stereotactic neuronavigation is inadequate.

Predictors of outcomes after surgery for medically intractable insular epilepsy: A systematic review and individual participant data meta-analysis.

Insular epilepsy (IE) is an increasingly recognized cause of drug-resistant epilepsy amenable to surgery. However, concerns of suboptimal seizure control and permanent neurological morbidity hamper widespread adoption of surgery for IE. We performed a systematic review and individual participant data meta-analysis to determine the efficacy and safety profile of surgery for IE and identify predictors of outcomes. Of 2483 unique citations, 24 retrospective studies reporting on 312 participants were eligible for inclusion. The median follow-up duration was 2.58 years (range, 0-17 years), and 206 (66.7%) patients were seizure-free at last follow-up. Younger age at surgery (≤18 years; HR = 1.70, 95% CI = 1.09-2.66, P = .022) and invasive EEG monitoring (HR = 1.97, 95% CI = 1.04-3.74, P = .039) were significantly associated with shorter time to seizure recurrence. Performing MR-guided laser ablation or radiofrequency ablation instead of open resection (OR = 2.05, 95% CI = 1.08-3.89, P = .028) was independently associated with suboptimal or poor seizure outcome (Engel II-IV) at last follow-up. Postoperative neurological complications occurred in 42.5% of patients, most commonly motor deficits (29.9%). Permanent neurological complications occurred in 7.8% of surgeries, including 5% and 1.4% rate of permanent motor deficits and dysphasia, respectively. Resection of the frontal operculum was independently associated with greater odds of motor deficits (OR = 2.75, 95% CI = 1.46-5.15, P = .002). Dominant-hemisphere resections were independently associated with dysphasia (OR = 13.09, 95% CI = 2.22-77.14, P = .005) albeit none of the observed language deficits were permanent. Surgery for IE is associated with a good efficacy/safety profile. Most patients experience seizure freedom, and neurological deficits are predominantly transient. Pediatric patients and those requiring invasive monitoring or undergoing stereotactic ablation procedures experience lower rates of seizure freedom. Transgression of the frontal operculum should be avoided if it is not deemed part of the epileptogenic zone. Well-selected candidates undergoing dominant-hemisphere resection are more likely to exhibit transient language deficits; however, the risk of permanent deficit is very low.

Corpus Callosotomy in the Modern Era: Origins, Efficacy, Technical Variations, Complications, and Indications.

Corpus callosotomy is among the oldest surgeries performed for drug-resistant epilepsy. Since it was first performed in 1940, numerous studies have assessed its outcomes in various patient populations in addition to describing different extents of sectioning and emerging technologies (i.e., endoscopic, laser interstitial thermal therapy, and radiosurgery). To capture the current state and offer a reappraisal, we comprehensively review the origins of corpus callosotomy, efficacy for various seizure types, technical variations, complications, and indications and compare the procedure with vagus nerve stimulation therapy, which has similar indications. We consider corpus callosotomy to be a safe and efficacious procedure, which should be considered by clinicians when appropriate. Furthermore, it can play an important role in treating patients with drug-resistant epilepsy when appropriate in low-to-middle-income countries where resources are limited.

Underutilization of advanced presurgical studies and high rates of vagus nerve stimulation for drug-resistant epilepsy: a single-center experience and recommendations.

INTRODUCTION: Epilepsy surgery continues to be profoundly underutilized despite its safety and effectiveness. We sought to investigate factors that may contribute to this phenomenon, with a particular focus on the antecedent underutilization of appropriate preoperative studies. METHODS: We reviewed patient data from a pediatric epilepsy clinic over an 18-month period. Patients with drug-resistant epilepsy (DRE) were categorized according to brain magnetic resonance imaging (MRI) findings (lesional, MRI-negative, or multifocal abnormalities) and type of epilepsy diagnosis based on semiology and electroencephalography (EEG) (focal or generalized). We then analyzed the rates of diagnostic test utilization, surgical referral, and subsequent epilepsy surgery as well as vagus nerve stimulation (VNS). RESULTS: Of the 249 patients with a diagnosis of epilepsy, 138 (55.4%) were found to have DRE. Excluding the 10 patients with DRE who did not undergo MRI, 76 patients (59.4%) were found to be MRI-negative (non-lesional epilepsy), 37 patients (28.9%) were found to have multifocal abnormalities, and 15 patients (11.7%) were found to have a single epileptogenic lesion on MRI (lesional epilepsy). Positron emission tomography (PET) and single-photon emission computed tomography (SPECT) were each completed in nine patients (7.0%) and magnetoencephalography (MEG) in four patients (3.1%). Despite the low utilization rate of adjunctive studies, over half (56.3%) ultimately underwent VNS alone, and 8.6% ultimately underwent definitive intracranial resection or disconnection surgery. CONCLUSIONS: The underutilization of appropriate non-invasive, presurgical testing in patients with focal DRE may in part explain the continued underutilization of definitive, resective/disconnective surgery. For patients without access to a high-volume, multidisciplinary surgical epilepsy center, adjunctive presurgical studies [e.g., PET, SPECT, MEG, electrical source imaging (ESI), EEG-functional magnetic resonance imaging (fMRI)], even when available, are rarely ordered, and this may contribute to excessive rates of VNS in lieu of definitive intracranial surgery.

A journey into the unknown: An ethnographic examination of drug-resistant epilepsy treatment and management in the United States.

Patients often recognize unmet needs that can improve patient-provider experiences in disease treatment management. These needs are rarely captured and may be hard to quantify in difficult-to-treat disease states such as drug-resistant epilepsy (DRE). To further understand challenges living with and managing DRE, a team of medical anthropologists conducted ethnographic field assessments with patients to qualitatively understand their experience with DRE across the United States. In addition, healthcare provider assessments were conducted in community clinics and Comprehensive Epilepsy Centers to further uncover patient-provider treatment gaps. We identified four distinct stages of the treatment and management journey defined by patients' perceived control over their epilepsy: Gripped in the Panic Zone, Diligently Tracking to Plan, Riding a Rollercoaster in the Dark, and Reframing Priorities to Redefine Treatment Success. We found that patients sought resources to streamline communication with their care team, enhanced education on treatment options beyond medications, and long-term resources to protect against a decline in control over managing their epilepsy once drug-resistant. Likewise, treatment management optimization strategies are provided to improve current DRE standard of care with respect to identified patient-provider gaps. These include the use of digital disease management tools, standardizing neuropsychiatrists into patients' initial care team, and introducing surgical and non-pharmacological treatment options upon epilepsy and DRE diagnoses, respectively. This ethnographic study uncovers numerous patient-provider gaps, thereby presenting a conceptual framework to advance DRE treatment. Further Incentivization from professional societies and healthcare systems to support standardization of the treatment optimization strategies provided herein into clinical practice is needed.

Completion Posterior Quadrant Disconnection After Failed Temporal Lobectomy: 2-Dimensional Operative Video.

Epilepsy is a chronic seizure disorder that affects about 1% of the global population.1 When seizure freedom cannot be obtained solely through antiseizure medicines (ASMs), the condition is termed medically refractory epilepsy (MRE).2,3 Though posterior quadrant disconnection (PQD) is underutilized in our experience, it is a highly effective surgical procedure for MRE restricted to the temporal, parietal, and/or occipital lobes.4-12 In this operative video, we demonstrate a right-sided completion PQD following failed temporal lobectomy in an 8-yr-old female with focal MRE. We review technical nuances, including (1) extension/revision of prior scalp incision, (2) placement of subdural strip for the identification of phase reversal and central sulcus, (3) disconnection of parietal and occipital lobes, (4) extension of the corticectomy to the pia overlying the falcotentorial junction and into the prior temporal lobectomy defect, and (5) posterior disconnection of the corpus callosum. Postoperatively, the patient experienced subtle left-arm weakness and central fever, both of which resolved. An external ventricular drain (EVD) was placed in the ventricle/operative cavity and left for 3 to 4 d until the draining cerebrospinal fluid (CSF) cleared. As of 3-mo follow-up, she has been seizure-free without complications. In summary, PQD is a safe and effective treatment option for MRE that can be utilized not only as an initial operation but also after failed surgery. Appropriate patient consent was obtained to perform this procedure and present this clinical case and surgical video for academic purposes. Image at 4:00 licensed under CC BY-2.5, 2006, modified from http://upload.wikimedia.org/wikipedia/commons/7/70/Lateral_head_skull.jpg (flipped and rotated). Image at 4:42, Public Domain: Gray H. Anatomy of the Human Body. 1918. Bartleby.com, https://commons.wikimedia.org/wiki/File:Lobes_of_the_brain_NL.svg; flipped, modified. Image at 6:42, Public Domain: House EL, Pansky B. A Functional Approach to Neuroanatomy. 1960. McGraw-Hill Book Company; https://upload.wikimedia.wikipedia.commons/5/52/Lawrence_1960_2.3.png; modified.

Surgical Clip Ligation of Anterior Communicating Artery Aneurysm in a Resource-Limited Setting.

Anterior communicating artery (ACOM) aneurysm clipping with intraoperative measures to ensure total occlusion and avoid ischemic complications is standard in countries such as the United States. However, alternatives need to be considered in resource-limited settings. The clipping of an unruptured, superiorly projecting ACOM aneurysm in a resource-limited setting is presented and special nuances that optimize safety are described. Careful surgical technique, meticulous identification of relevant anatomy, post-ligation inspection of the aneurysm and adjacent vessels, and possibly needle puncture of the aneurysm dome are critical to achieve favorable results.

Total and partial posterior quadrant disconnection for medically refractory epilepsy: A systematic review.

PURPOSE: Posterior quadrant disconnection (PQD) is a surgical procedure for medically refractory epilepsy (MRE) involving diffuse regions of the temporo-parieto-occipital lobes. We sought to compare factors and efficacy according to PQD extent. METHODS: We performed a systematic review of the literature reporting the use of PQD since 2004. We analyzed various characteristics of pooled cases, including the role of preoperative studies in patient selection, intraoperative techniques, and outcomes. RESULTS: Our review of 137 patients from nine studies revealed 66% undergoing total PQD and 34% undergoing partial PQD. Interictal electroencephalography (EEG) findings were predominantly characterized as lateralized for total PQD (56%) and localized within the ipsilateral posterior quadrant in patients undergoing partial PQD (53%). Metabolic functional studies [positron emission tomography (PET) or ictal single-photon emission computed tomography (SPECT)] played a role in surgical decision-making in 42% of patients who underwent total PQD. Wada and/or functional magnetic resonance imaging (fMRI) was more often utilized for partial PQD (22%) than total PQD (3%) as was intracranial electroencephalography (icEEG) (30% versus 13%, respectively). Overall, 75% of total PQD patients achieved seizure freedom [defined as Engel I or International League Against Epilepsy (ILAE) Class 1 outcome] in comparison to 63% of partial PQD patients (p = .078). New visual field deficits were seen in 12% and new or worsened hemiparesis in 6%. For patients in either cohort, concordance of interictal and ictal EEG findings was found to be predictive of seizure freedom (p = .048). CONCLUSION: Both total and partial PQD represent effective alternatives for managing patients with MRE whose seizure onset zone (SOZ) involves a diffuse region within the posterior quadrant. While PET and/or SPECT frequently aided in the decision to proceed with total PQD, patients who underwent a tailored, partial multilobar resection were more likely to undergo Wada and/or fMRI testing as well as stage I icEEG studies.

The Co-Pilot Project: An International Neurosurgical Collaboration in Ukraine.

OBJECTIVE: We aim to provide a thorough description of the efforts and outcomes of the Co-Pilot Project in Ukraine, which facilitates neurosurgical collaboration between American and Ukrainian physicians. METHODS: The Co-Pilot Project, which operates under its parent nonprofit organization, Razom, organized multiple trips for American physicians to Ukraine. Activities included consulting in clinic, assisting with neurosurgical operations, and providing didactic lectures. Further efforts have included coordinating training opportunities for Ukrainian surgeons. We retrospectively reviewed all operations performed by Ukrainian partner physicians alongside American co-pilot physicians across Ukraine since August 2016. RESULTS: Teams of Ukrainian and American physicians operated on 78 patients (24 children and 54 adults) for a total of 84 procedures in 5 different cities (Kyiv, Lutsk, Lviv, Odessa, and Stryi) of Ukraine. Operations were classified into the following categories: adult brain tumors (n = 39), adult spine tumors (n = 1), epilepsy (n = 9), pain (n = 2), pediatric brain tumors (n = 11), vascular/endovascular (n = 10), and miscellaneous (n = 12). Four illustrative cases are described in detail. Of the patients with brain tumors, 43.5% (20/46) had giant tumors, and gross total resection or near-total resection was achieved in 78.3% (36/46). CONCLUSIONS: Profound disparities in neurosurgical care exist globally, which has led to the formation of collaborative relationships between physicians from various countries. We hope that the work of the Co-Pilot Project in Ukraine can serve as a template for effective international neurosurgical collaboration in other low-to-middle-income countries.

Sodium Fluorescein-Guided Gross Total Resection of Pediatric Exophytic Brainstem Glioma: 2-Dimensional Operative Video.

Brainstem gliomas comprise 10% to 20% of pediatric intracranial tumors.1 Gross total resection is associated with the greatest long-term survival.1 However, due to the eloquence of surrounding brain tissue, an aggressive resection is not always achievable and can be associated with significant risk.2 Sodium fluorescein can be used to help differentiate between tumor and normal tissue.3,4 In this operative video, we demonstrate the step-by-step technique to utilize fluorescence in surgically resecting an exophytic glioma arising from the midbrain in a 16-yr-old male. Technical nuances are highlighted in this operative video, including the use of the YELLOW 560 (Zeiss) filter to differentiate fluorescent tumor from normal tissue as well as strategic splitting of the tentorium to expose the supratentorial component of the tumor. A decrease in motor potentials of the right leg during the case did not translate into neurological worsening postoperatively; at 3-mo follow-up, the patient attests to better strength and coordination on his affected side. In summary, sodium fluorescein can be used as a critical adjunctive tool for successful surgery in the case of a brainstem tumor. Alternatives to this procedure included gross total resection with 5-aminolevulinic acid, subtotal resection with chemotherapy, and active monitoring, but were not chosen due to their limitations in this clinical case.5-7 Appropriate patient consent was obtained to perform this procedure and present this clinical case and surgical video for academic purposes.

Microsurgical Clip Ligation of an Unruptured Azygos Bifurcation Aneurysm Indented by the Falx Cerebri: 3-Dimensional Operative Video.

Dissecting pericallosal aneurysms from the falx cerebri is technically challenging, as one must release the adherent dome but minimize shearing injury, which could result in intraoperative rupture. We discuss a 51-yr-old woman with a history of hypertension and smoking who presented with severe headaches and was found to have a 6-mm unruptured, multilobulated pericallosal aneurysm abutting the falx, with anterior and superior projecting domes on either side. She also had an azygos anterior cerebral artery (ACA), a rare anatomic variant associated with pericallosal aneurysms, where both A1 segments form a single A2. After considering endovascular and open surgical techniques, we proceeded with clip ligation given her younger age, smoking history, daughter aneurysms seen on angiography, and azygos ACA. We positioned her supine with her head turned lateral, left side down to maximize gravitational retraction, mapped a bicoronal incision, and performed a small craniotomy, followed by an interhemispheric approach. Rather than cutting the falx around the dome, a described technique that risks blind vessel injury, we temporarily clipped inflow vessels to reduce the dome's turgor and sharply and bluntly dissected apart its attachments, which freed the aneurysm from beneath the falx and allowed visualization of associated vessels. Using suction to manipulate the dome, we then placed stacked, angled clips, and used a micro-Doppler to confirm brisk inflow and outflow. Postoperatively, she was neurologically intact, and her angiogram showed no residual aneurysm. Our 3-dimensional video demonstrates a safer, alternative approach to treating this rare aneurysm with its associated anatomical variant. Patient consented to her clinical presentation and microscope media being used for academic purposes.

Open Resection versus Laser Interstitial Thermal Therapy for the Treatment of Pediatric Insular Epilepsy.

BACKGROUND: Various studies suggest that the insular cortex may play an underappreciated role in pediatric frontotemporal/parietal epilepsy. Here, we report on the postsurgical outcomes in 26 pediatric patients with confirmed insular involvement by depth electrode monitoring. OBJECTIVE: To describe one of the largest series of pediatric patients with medically refractory epilepsy undergoing laser interstitial thermal therapy (LITT) or surgical resection of at least some portion of the insular cortex. METHODS: Pediatric patients in whom invasive insular sampling confirmed insular involvement and who subsequently underwent a second stage surgery (LITT or open resection) were included. Complications and Engel Class outcomes at least 1 yr postsurgery were compiled as well as pathology results in the open surgical cases. RESULTS: The average age in our cohort was 10.3 yr, 58% were male, and the average length of follow-up was 2.43 ± 0.20 (SEM) yr. A total of 14 patients underwent LITT, whereas 12 patients underwent open resection. Complications in patients undergoing either LITT or open resection were mostly minimal and generally transient. Forty-three percent of patients who underwent LITT were Engel Class I, compared to 50% of patients who underwent open insular resection. CONCLUSION: Both surgical resection and LITT are valid management options in the treatment of medically refractory insular/opercular epilepsy in children. Although LITT may be a less invasive alternative to craniotomy, further studies are needed to determine its noninferiority in terms of complication rates and seizure freedom, especially in cases of cortical dysplasia that may involve extensive regions of the brain.

Traumatic Occipitocervical Distraction Injuries in Children: A Systematic Review.

BACKGROUND: Occipitocervical distraction injuries (OCDI) in children occur on a wide spectrum of severity, and decisions about treatment suffer from a lack of rigorous guidelines and significant inter-institutional variability. While clear cases of frank atlanto-occipital dislocation (AOD) are treated with surgical stabilization, the approach for less severe cases of OCDI is not standardized. These patients require a careful assessment of both radiographic and clinical criteria, as part of a complex risk-benefit analysis, to establish whether occipitocervical fusion (OCF) is indicated. Here, we performed a systematic review of the literature that describes traumatic OCDI in children < 18 years of age. SUMMARY: We performed a systematic review, according to PRISMA guidelines, of children < 18 years of age presenting with traumatic etiologies of OCDI. We searched PubMed to identify papers congruent with these criteria. Exclusion criteria included (1) reports on atraumatic causes of OCDI and (2) studies with insufficient clinical and radiographic details on individual patients. We identified 16 reports describing a total of 144 patients treated for pediatric traumatic OCDI. Based on the synthesis of these findings and the collective experience of the authors, we present the demographic, clinical, and radiographic factors that underlie OC instability, which we hope will serve as components of a grading system in the future. We considered various clinical and radiographic findings including: (1) the mechanism of injury, (2) the patient's age, (3) CT/CT angiography of head and neck findings and parameters, (4) MRI findings, and (5) neurological exam, for the purpose of determining the severity of the OCDI and offering treatment guidelines based on the summative risk of underlying OC instability. Key Messages: OCDI is a potentially devastating injury, especially in children. Although missing the diagnosis can have potentially catastrophic consequences, reverting to surgical fixation in less severe cases can subject children to unnecessary operative risk and permanently reduce their range of motion. After reviewing all the available reports of pediatric traumatic OCDI in the neurosurgical literature, we propose an outline of clinical and radiographic factors influencing underlying OC instability that could be incorporated into a grading scale to guide treatment. We hope this study stimulates discussion on the standardization of treatment for pediatric OCDI.

Invasive Insular Sampling in Pediatric Epilepsy: A Single-Institution Experience.

BACKGROUND: It has been increasingly recognized that the insular cortex plays an important role in frontotemporal-parietal epilepsy in children. The insula, however, cannot be properly interrogated with conventional subdural grids, and its anatomy makes it difficult to implicate the insula with semiology or noninvasive modalities. Frame-based, stereotactic placement of insular depth electrodes for direct extraoperative monitoring is a relatively low-risk maneuver that allows for conclusive interrogation of this region, and, in select cases, can easily be replaced with a laser applicator for minimally invasive treatment via thermoablation. OBJECTIVE: To describe the largest reported series of pediatric patients with refractory epilepsy undergoing insular depth electrode placement. METHODS: We used current procedural terminology billing records to identify cases of depth electrode insertion performed at our institution. Clinical information from patients undergoing invasive insular sampling was then retrospectively collected. RESULTS: Seventy-four insular depth electrodes were placed in 49 patients for extraoperative, inpatient monitoring. The decision to place insular depth electrodes was determined by a multidisciplinary epilepsy team. In 65.3% of cases, direct invasive sampling implicated the insula in seizure onset and prompted either thermoablation or surgical resection of some portion of the insula. There were no serious adverse effects or complications associated with the placement of insular depth electrodes. CONCLUSION: Given the low morbidity of insular depth electrode insertion and the high proportion of patients who exhibited insular involvement, it is worth considering whether insular depth electrodes should be part of the standard presurgical evaluation in children with treatment-refractory frontotemporal-parietal epilepsy.

Instrumented fusion in a 12-month-old with atlanto-occipital dislocation: case report and literature review of infant occipitocervical fusion.

BACKGROUND: The treatment of atlantoaxial dislocation in very young children is challenging and lacks a consensus management strategy. DISCUSSION: We review the literature on infantile occipitocervical (OC) fusion is appraised and technical considerations are organized for ease of reference. Surgical decisions such as graft type and instrumentation details are summarized, along with the use of bone morphogenic protein and post-operative orthoses. ILLUSTRATIVE CASE: We present the case of a 12-month-old who underwent instrumented occipitocervical (OC) fusion in the setting of traumatic atlanto-occipital dislocation (AOD). CONCLUSION: Occipitocervical (OC) arthrodesis is obtainable in very young infants and children. Surgical approaches are variable and use a combination of autologous grafting and creative screw and/or wire constructs. The heterogeneity of pathologic etiology leading to OC fusion makes it difficult to make definitive recommendations for surgical management.