Efficacy of Occipital Nerve Stimulation in Trigeminal Autonomic Cephalalgias: A Systematic Review.

BACKGROUND: Trigeminal autonomic cephalalgias (TACs) are a group of highly disabling primary headache disorders. Although pharmacological treatments exist, they are not always effective or well tolerated. Occipital nerve stimulation (ONS) is a potentially effective surgical treatment. OBJECTIVE: To perform a systematic review of the efficacy of ONS in treating TACs. METHODS: A systematic review was performed using Medline, Embase, and Cochrane databases. Primary outcomes were reduction in headache intensity, duration, and frequency. Secondary outcomes included adverse event rate and reduction in medication use. Because of large differences in outcome measures, data for patients suffering from short-lasting, unilateral, and neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and cranial autonomic symptoms (SUNA) were reported separately. Risk of bias was assessed using the NIH Quality Assessment Tools. RESULTS: A total of 417 patients from 14 published papers were included in the analysis, of which 15 patients were in the SUNCT/SUNA cohort. The mean reduction in headache intensity and duration was 26.2% and 31.4%, respectively. There was a mean reduction in headache frequency of 50%, as well as a 61.2% reduction in the use of abortive medications and a 31.1% reduction in the use of prophylactic medications. In the SUNCT/SUNA cohort, the mean decrease in headache intensity and duration was 56.8% and 42.8%. The overall responder rate, defined as a >50% reduction in attack frequency, was 60.8% for the non-SUNCT/non-SUNA cohort and 66.7% for the SUNCT/SUNA cohort. Adverse events requiring repeat surgery were reported in 33% of cases. Risk of bias assessment suggests that articles included in this review had reasonable internal validity. CONCLUSION: ONS may be an effective surgical treatment for approximately two thirds of patients with medically refractory TACs.

A rapid theta network mechanism for flexible information encoding.

Flexible behavior requires gating mechanisms that encode only task-relevant information in working memory. Extant literature supports a theoretical division of labor whereby lateral frontoparietal interactions underlie information maintenance and the striatum enacts the gate. Here, we reveal neocortical gating mechanisms in intracranial EEG patients by identifying rapid, within-trial changes in regional and inter-regional activities that predict subsequent behavioral outputs. Results first demonstrate information accumulation mechanisms that extend prior fMRI (i.e., regional high-frequency activity) and EEG evidence (inter-regional theta synchrony) of distributed neocortical networks in working memory. Second, results demonstrate that rapid changes in theta synchrony, reflected in changing patterns of default mode network connectivity, support filtering. Graph theoretical analyses further linked filtering in task-relevant information and filtering out irrelevant information to dorsal and ventral attention networks, respectively. Results establish a rapid neocortical theta network mechanism for flexible information encoding, a role previously attributed to the striatum.

Complications of Deep Brain Stimulation for Parkinson Disease and Relationship between Micro-electrode tracks and hemorrhage: Systematic Review and Meta-Analysis.

BACKGROUND: Deep brain stimulation is a common treatment for Parkinson's disease (PD). Despite strong efficacy in well-selected patients, complications can occur. Intraoperative micro-electrode recording (MER) can enhance efficacy by improving lead accuracy. However, there is controversy as to whether MER increases risk of hemorrhage. OBJECTIVES: To provide a comprehensive systematic review and meta-analysis reporting complication rates from deep brain stimulation in PD. We also interrogate the association between hemorrhage and MER. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were implemented while querying the Pubmed, Embase, and Cochrane databases. All included studies were randomized controlled trials and prospective case series with 5 or more patients. Primary outcomes included rates of overall revision, infection, lead malposition, surgical site and wound complications, hardware-related complications, and seizure. The secondary outcome was the relationship between number of MER tracks and hemorrhage rate. RESULTS: 262 articles with 21,261 patients were included in the analysis. Mean follow-up was 25.8 months (range 0-133). Complication rates were: revision 4.9%, infection 4.2%, lead malposition 3.3%, surgical site complications 2.8%, hemorrhage 2.4%, hardware-related complications 2.4%, and seizure 1.9%. While hemorrhage rate did not increase with single-track MER (odds ratio, 3.49; P = 0.29), there was a significant non-linear increase with each additional track. CONCLUSION: Infection and lead malposition were the most common complications. Hemorrhage risk increases with more than one MER track. These results highlight the challenge of balancing surgical accuracy and perioperative risk.

Intracranial recordings reveal high-frequency activity in the human temporal-parietal cortex supporting non-literal language processing.

Objective: Non-literal expressions such as sarcasm, metaphor and simile refer to words and sentences that convey meanings or intentions that are different and more abstract than literal expressions. Neuroimaging studies have shown activations in a variety of frontal, parietal and temporal brain regions implicated in non-literal language processing. However, neurophysiological correlates of these brain areas underlying non-literal processing remain underexplored. Methods: To address this, we investigated patterns of intracranial EEG activity during non-literal processing by leveraging a unique patient population. Seven neurosurgical patients with invasive electrophysiological monitoring of superficial brain activity were recruited. Intracranial neural responses were recorded over the temporal-parietal junction (TPJ) and its surrounding areas while patients performed a language task. Participants listened to vignettes that ended with non-literal or literal statements and were then asked related questions to which they responded verbally. Results: We found differential neurophysiological activity during the processing of non-literal statements as compared to literal statements, especially in low-Gamma (30-70 Hz) and delta (1-4 Hz) bands. In addition, we found that neural responses related to non-literal processing in the high-gamma band (>70 Hz) were significantly more prominent at TPJ electrodes as compared to non-TPJ (i.e., control) electrodes in most subjects. Moreover, in half of patients, high-gamma activity related to non-literal processing was accompanied by delta-band modulation. Conclusion: These results suggest that both low- and high-frequency electrophysiological activities in the temporal-parietal junction play a crucial role during non-literal language processing in the human brain. The current investigation, utilizing better spatial and temporal resolution of human intracranial electrocorticography, provides a unique opportunity to gain insights into the localized brain dynamics of the TPJ during the processing of non-literal language expressions.

Subthalamic nucleus deep brain stimulation programming settings do not correlate with Parkinson's disease severity.

BACKGROUND: Deep brain stimulation (DBS) is a well-established treatment for Parkinson's disease (PD). While the success of DBS is dependent on careful patient selection and accurate lead placement, programming parameters play a pivotal role in tailoring therapy on the individual level. Various algorithms have been developed to streamline the initial programming process, but the relationship between pre-operative patient characteristics and post-operative device settings is unclear. In this study, we investigated how PD severity correlates with DBS settings. METHODS: We conducted a retrospective review of PD patients who underwent DBS of the subthalamic nucleus at one US tertiary care center between 2014 and 2018. Pre-operative patient characteristics and post-operative programming data at various intervals were collected. Disease severity was measured using the Unified Parkinson's Disease Rating Scale score (UPDRS) as well as levodopa equivalent dose (LED). Correlation analyses were conducted looking for associations between pre-operative disease severity and post-operative programming parameters. RESULTS: Fifty-six patients were analyzed. There was no correlation between disease severity and any of the corresponding programming parameters. Pre-operative UPDRS scores on medication were similar to post-operative scores with DBS. Settings of amplitude, frequency, and pulse width increased significantly from 1 to 6 months post-operatively. Stimulation volume, inferred by the distance between contacts used, also increased significantly over time. CONCLUSIONS: Interestingly, we found that patients with more advanced disease responded to electrical stimulation similarly to patients with less advanced disease. These data provide foundational knowledge of DBS programming parameters used in a single cohort of PD patients over time.

The impact of sub specialization within functional neurosurgery on patient outcomes in a comprehensive epilepsy center.

BACKGROUND: One in three patients with epilepsy are medication-refractory and may benefit from investigations and operative treatment at a comprehensive epilepsy center. However, while these centers have capabilities for advanced seizure monitoring and surgical intervention, they are not required to have a functional neurosurgeon who is primarily focused in epilepsy surgery. Therefore, the objective of this study is to determine the impact of having a sub-specialized, epilepsy-focused functional neurosurgeon on patient outcomes. METHODS: We conducted a retrospective chart review for all patients who underwent surgical intervention for medically refractory epilepsy at a Level 4 comprehensive Epilepsy Center from 2008 through 2019. Data was divided into two groups: group 1 comprised patients who had surgery before the hiring of a dedicated epilepsy-focused functional neurosurgeon in 2016, and group 2 was afterwards. We compared surgical procedures, significant complications, and seizure outcomes. RESULTS: A total of 101 patients underwent 105 operations (52 in group 1 and 53 in group 2), not including intracranial EEG insertion. Compared to group 1, group 2 had more surgeries performed per year (15.1 vs. 6.5), and a significantly lower Engel score at last follow-up (1.78 vs. 2.57; p < 0.001). There was no difference in percentage of cases undergoing iEEG, and no difference in complication rates. CONCLUSIONS: In this series, the hiring of a sub-specialized functional neurosurgeon dedicated to epilepsy surgery in a comprehensive epilepsy center was associated with an increase in surgical volume and improved seizure outcomes.

Seizure-related apneas have an inconsistent linkage to amygdala seizure spread.

OBJECTIVE: Sudden unexpected death in epilepsy (SUDEP) is a frequent cause of death in epilepsy. Respiratory dysfunction is implicated as a critical factor in SUDEP pathophysiology. Human studies have shown that electrical stimulation of the amygdala resulted in apnea, indicating that the amygdala has a role in respiration control. Unilateral amygdala stimulation resulted in immediate onset of respiratory dysfunction occurring only during nose breathing. In small numbers of patients, some but not all spontaneous seizures resulted in apnea occurring shortly after seizure spread to the amygdala. With this study we aimed to determine whether seizure onset or spread to the amygdala was necessary and sufficient to cause apnea. METHODS: We investigated the temporal relationship between apnea/hypopnea (AH) onset and initial seizure involvement within the amygdala in patients with implanted depth electrodes. RESULTS: Data from 17 patients (11 female) with 47 seizures were analyzed. With seven seizures (three patients), AH preceded amygdala seizure involvement by 2 to 55 seconds. There was no AH with four seizures (three patients) that involved the amygdala. With eight seizures (four patients) AH occurred within 2 seconds following amygdala seizure onset. With 28 seizures, AH started >2 seconds after amygdala seizure onset (range 3-158 seconds). Following seizure onset, there was a significant difference between AH onset time and amygdala seizure onset (P < .001). The mean ± standard deviation (SD) AH onset was 27.8 ± 41.06 seconds, and the mean time to amygdala involvement was 8.83 ± 20.19 seconds. SIGNIFICANCE: There is a wide range of AH onset times relative to amygdala seizure involvement. With some seizures, amygdala seizure involvement occurs without AH. With other seizures, AH precedes amygdala seizures, suggesting that, with spontaneous seizures, involvement of the amygdala may not be crucial to induction of AH with all seizures. Other pathophysiology impacting brainstem respiratory networks may be of greater relevance to seizure-triggered apneas.

Superior accuracy and precision of SEEG electrode insertion with frame-based vs. frameless stereotaxy methods.

BACKGROUND: Stereotactic electroencephalography (SEEG) has largely become the preferred method for intracranial seizure localization in epileptic patients due to its low morbidity and minimally invasive approach. While robotic placement is gaining popularity, many centers continue to use manual frame-based and frameless methods for electrode insertion. However, it is unclear how these methods compare in regard to accuracy, precision, and safety. Here, we aim to compare frame-based insertion using a CRW frame (Integra®) and frameless insertion using the StealthStation™ S7 (Medtronic®) navigation system for common temporal SEEG targets. METHODS: We retrospectively examined electrode targets in SEEG patients that were implanted with either frame-based or frameless methods at a level 4 epilepsy center. We focused on two commonly used targets: amygdala and hippocampal head. Stealth station software was used to merge pre-operative MR with post-operative CT images for each patient, and coordinates for each electrode tip were calculated in relation to the midcommissural point. These were compared to predetermined ideal coordinates in regard to error and directional bias. RESULTS: A total of 81 SEEG electrodes were identified in 23 patients (40 amygdala and 41 hippocampal head). Eight of 45 electrodes (18%) placed with the frameless technique and 0 of 36 electrodes (0%) placed with the frame-based technique missed their target and were not clinically useful. The average Euclidean distance comparing actual to ideal electrode tip coordinates for frameless vs. frame-based techniques was 11.0 mm vs. 7.1 mm (p < 0.001) for the amygdala and 12.4 mm vs. 8.5 mm (p < 0.001) for the hippocampal head, respectively. There were no hemorrhages or clinical complications in either group. CONCLUSIONS: Based on this series, frame-based SEEG insertion is significantly more accurate and precise and results in more clinically useful electrode contacts, compared to frameless insertion using a navigation guidance system. This has important implications for centers not currently using robotic insertion.

Comparison of Intraoperative Computed Tomography Scan with Postoperative Magnetic Resonance Imaging for Determining Deep Brain Stimulation Electrode Coordinates.

BACKGROUND: Deep brain stimulation (DBS) is an effective therapy for a variety of refractory movement disorders. Accurate lead placement in the target nucleus is critical to ensure therapeutic effects and to minimize side effects, and intraoperative computed tomography (iCT) scan has been used to target and confirm lead position. The objective of this study is to compare the accuracy of determining the x, y, and z coordinates of final lead placement using iCT scan relative to postoperative magnetic resonance imaging (MRI). METHODS: We conducted a retrospective study on 83 patients who underwent insertion of 145 DBS leads from 2015 to 2017 at a single institution. iCT scan was merged with the preoperative MRI to determine lead coordinates on both magnetic resonance and computed tomography images independently, and the absolute differences between the x, y, and z coordinates between the 2 scans along with the Euclidean vectors were calculated. RESULTS: The mean absolute differences ± standard error of the mean between iCT scan and postoperative MRI coordinates were as follows: x = 0.01 ± 0.09 mm (P = 0.89), y = 1.67 ± 0.14 mm (P < 0.001), and z = 2.75 ± 0.15 mm (P < 0.001). The average Euclidean vector difference was 3.21 ± 0.15 mm (P < 0.001). CONCLUSIONS: Significant differences exist between iCT scan and postoperative MRI DBS y and z lead coordinates, but not with x coordinates. Based on this series, iCT scan is more accurate when confirming x coordinates, and less accurate for confirming y and z coordinates during DBS operations.

Salary Trends Across American Subspecialties in Academic Neurosurgery.

Enthusiasm for research and teaching are often the main reasons neurosurgical residents choose academic careers, and subspecialty choice usually stems from an interest in that particular field. However, recent salary data bring to light a work relative value unit-related trend in American academic neurosurgeon salaries, one that is similar to private practice, where compensation is strongly correlated with clinical productivity. In addition, there are significant disparities in how various subspecialties are remunerated in academic settings. For example, functional and pediatric specialists earn significantly lower salaries on average compared with their spine and endovascular colleagues. These trends have important implications both for neurosurgical trainees and for institutions in the United States.

Real-time augmented reality for delineation of surgical margins during neurosurgery using autofluorescence lifetime contrast.

Current clinical brain imaging techniques used for surgical planning of tumor resection lack intraoperative and real-time feedback; hence surgeons ultimately rely on subjective evaluation to identify tumor areas and margins. We report a fluorescence lifetime imaging (FLIm) instrument (excitation: 355 nm; emission spectral bands: 390/40 nm, 470/28 nm, 542/50 nm and 629/53 nm) that integrates with surgical microscopes to provide real-time intraoperative augmentation of the surgical field of view with fluorescent derived parameters encoding diagnostic information. We show the functionality and safety features of this instrument during neurosurgical procedures in patients undergoing craniotomy for the resection of brain tumors and/or tissue with radiation damage. We demonstrate in three case studies the ability of this instrument to resolve distinct tissue types and pathology including cortex, white matter, tumor and radiation-induced necrosis. In particular, two patients with effects of radiation-induced necrosis exhibited longer fluorescence lifetimes and increased optical redox ratio on the necrotic tissue with respect to non-affected cortex, and an oligodendroglioma resected from a third patient reported shorter fluorescence lifetime and a decrease in optical redox ratio than the surrounding white matter. These results encourage the use of FLIm as a label-free and non-invasive intraoperative tool for neurosurgical guidance.

Trigeminal Neuralgia: Medical Management and Surgical Options.

Questions from patients about pain conditions and analgesic pharmacotherapy and responses from authors are presented to help educate patients and make them more effective self-advocates. In response to a question about trigeminal neuralgia, its diagnosis, medical therapies, surgical procedures, and treatment outcomes will be discussed.

From adagio to allegretto: The changing tempo of theta frequencies in epilepsy and its relation to interneuron function.

Despite decades of research, our understanding of epilepsy, including how seizures are generated and propagate, is incomplete. However, there is growing recognition that epilepsy is more than just the occurrence of seizures, with patients often experiencing comorbid deficits in cognition that are poorly understood. In addition, the available therapies for treatment of epilepsy, from pharmaceutical treatment to surgical resection and seizure prevention devices, often exacerbate deficits in cognitive function. In this review, we discuss the hypothesis that seizure generation and cognitive deficits have a similar pathological source characterized by, but not limited to, deficits in theta oscillations and their influence on interneurons. We present a new framework that describes oscillatory states in epilepsy as alternating between hyper- and hypo-synchrony rather than solely the spontaneous transition to hyper-excitability characterized by the seizures. This framework suggests that as neural oscillations, specifically in the theta range, vary their tempo from a slowed almost adagio tempo during interictal periods to faster, more rhythmic allegretto tempo preictally, they impact the function of interneurons, modulating their ability to control seizures and their role in cognitive processing. This slow wave oscillatory framework may help explain why current therapies that work to reduce hyper-excitability do not completely eliminate seizures and often lead to exacerbated cognitive deficits.

Patient satisfaction with epilepsy surgery: what is important to patients?

Patient satisfaction with therapeutic interventions is an important outcome of care. Although generic measures of patient satisfaction exist, there is no validated scale for measuring patient satisfaction with epilepsy surgery. We aimed to systematically obtain patient-identified factors related to satisfaction with epilepsy surgery as a means of informing clinicians about the ways that patients evaluate outcomes of their treatment and as a conceptual basis for the future development of epilepsy surgery patient satisfaction scales. Focus group discussions with epilepsy surgery patients (n=9) were conducted to identify themes relevant to patient satisfaction with epilepsy surgery and to draft initial items of importance. Consensus methodology (Delphi technique) was used to obtain expert opinion (n=13) to refine the items. Member-checking with focus group participants was performed to ensure the identified items were relevant, clear, and inclusive. A list of 31 items embodied 12 themes related to patient-reported satisfaction with epilepsy surgery. These included adverse effects, medical care or rehabilitation, seizure control, post-operative recovery, anti-seizure medication, independence, seizure worry, ability to drive, social relationships, self-confidence, improved cognitive function, and improved physical health. This study used a systematic approach to identify factors that are important to patients when assessing satisfaction with epilepsy surgery. This knowledge can assist clinicians caring for these patients and is also a critical step towards the validation of a formal scale to assess satisfaction with epilepsy surgery.

Review of the Neural Oscillations Underlying Meditation.

Objective: Meditation is one type of mental training that has been shown to produce many cognitive benefits. Meditation practice is associated with improvement in concentration and reduction of stress, depression, and anxiety symptoms. Furthermore, different forms of meditation training are now being used as interventions for a variety of psychological and somatic illnesses. These benefits are thought to occur as a result of neurophysiologic changes. The most commonly studied specific meditation practices are focused attention (FA), open-monitoring (OM), as well as transcendental meditation (TM), and loving-kindness (LK) meditation. In this review, we compare the neural oscillatory patterns during these forms of meditation. Method: We performed a systematic review of neural oscillations during FA, OM, TM, and LK meditation practices, comparing meditators to meditation-naïve adults. Results: FA, OM, TM, and LK meditation are associated with global increases in oscillatory activity in meditators compared to meditation-naïve adults, with larger changes occurring as the length of meditation training increases. While FA and OM are related to increases in anterior theta activity, only FA is associated with changes in posterior theta oscillations. Alpha activity increases in posterior brain regions during both FA and OM. In anterior regions, FA shows a bilateral increase in alpha power, while OM shows a decrease only in left-sided power. Gamma activity in these meditation practices is similar in frontal regions, but increases are variable in parietal and occipital regions. Conclusions: The current literature suggests distinct differences in neural oscillatory activity among FA, OM, TM, and LK meditation practices. Further characterizing these oscillatory changes may better elucidate the cognitive and therapeutic effects of specific meditation practices, and potentially lead to the development of novel neuromodulation targets to take advantage of their benefits.

Toward a Neuroscience of Adult Cognitive Developmental Theory.

Piaget's genetic epistemology has provided the constructivist approach upon which child developmental theories were founded, in that infants are thought to progress through distinct cognitive stages until they reach maturity in their early 20's. However, it is now well established that cognition continues to develop after early adulthood, and several "neo-Piagetian" theories have emerged in an attempt to better characterize adult cognitive development. For example, Kegan's Constructive Developmental Theory (CDT) argues that the thought processes used by adults to construct their reality change over time, and reaching higher stages of cognitive development entails becoming objectively aware of emotions and beliefs that were previously in the realm of the subconscious. In recent years, neuroscience has shown a growing interest in the biological substrates and neural mechanisms encompassing adult cognitive development, because psychological and psychiatric disorders can arise from deficiencies therein. In this article, we will use Kegan's CDT as a framework to discuss adult cognitive development in relation to closely correlated existing constructs underlying social processing, such as the perception of self and others. We will review the functional imaging and electrophysiologic evidence behind two key concepts relating to these posited developmental changes. These include self-related processing, a field that distinguishes between having conscious experiences ("being a self") and being aware of oneself having conscious experiences ("being aware of being a self"); and theory of mind, which is the objective awareness of possessing mental states such as beliefs and desires (i.e., having a "mind") and the understanding that others possess mental states that can be different from one's own. We shall see that cortical midline structures, including the medial prefrontal cortex and cingulate gyrus, as well as the temporal lobe, are associated with psychological tasks that test these models. In addition, we will review computational modeling approaches to cognitive development, and show how mathematical modeling can provide insights into how sometimes continuous changes in the neural processing substrate can give rise to relatively discrete developmental stages. Because deficiencies in adult cognitive development can result in disorders such as autism and depression, bridging the gaps between developmental psychology, neuroscience, and modeling has potential implications for clinical practice. As neuromodulation techniques such as deep brain and transcranial stimulation continue to advance, interfacing with these systems may lead to the emergence of novel investigational methods and therapeutic strategies in adults suffering from developmental disorders.

Implementation of a "Flipped Classroom" for Neurosurgery Resident Education.

INTRODUCTION: Engaging residents across a multiyear training spectrum is challenging given the heterogeneity of experience and limited time available for educational activities. A "flipped classroom" model, in which residents prepare ahead of time for mentored topic discussions, has potential advantages. METHODS: We implemented a curriculum consisting of topics distributed across the specialty. Weekly, each resident was randomly assigned to research a specific aspect of an assigned topic appropriate to his or her level of experience: junior residents about what characterizes each clinical entity, midlevel residents about when to intervene, and chief residents about how to administer treatment. Residents completed an anonymous survey 6 months after implementation. Board examination performance was assessed before and after implementation. RESULTS: A total of 12 residents participated in the program. Weekly, 1.75±0.40 hours were spent in preparation, with senior residents reporting less time than junior residents. All residents indicated that the accumulation of experience across 7 years of residency was a major advantage of this program, and all preferred it to lectures. Performance on the board examination significantly increased after implementation (from 316±36 to 468±45, p<0.05). CONCLUSIONS: The flipped classroom is a viable approach to resident education and is associated with increased engagement and improved performance using validated knowledge-assessment tools.

Resection of Temporal Neocortex During Multiple Hippocampal Transections for Mesial Temporal Lobe Epilepsy Does not Affect Seizure or Memory Outcome.

BACKGROUND: Multiple hippocampal transection (MHT) is a surgical treatment for mesial temporal lobe epilepsy associated with improved postoperative neuropsychological outcomes compared with lobectomy. OBJECTIVE: To determine whether resection of the amygdala and anterior temporal neocortex during MHT affects postoperative seizure/memory outcome. METHODS: Seventeen patients with normal magnetic resonance imaging and stereo-electroencephalogram-proven drug-resistant dominant mesial temporal lobe epilepsy were treated with MHT. Nine patients underwent MHT alone (MHT-) and 8 patients underwent MHT plus removal of the amygdala and anterior 4.5 cm of temporal neocortex lateral to the fusiform gyrus (MHT+). Verbal and visual-spatial memory were assessed in all patients preoperatively and in 14 patients postoperatively using the Wechsler Memory Scale. Postoperative seizure control was assessed at 12 months for all patients. RESULTS: Overall, 11 of 17 patients (64.7%) were Engel class 1 at 1 year (6/9 MHT-, 5/8 MHT+, P = .38), and 10 of 14 patients (71.4%) had no significant postoperative decline in either verbal or visual memory (6/8 MHT-, 4/6 MHT+, P = .42). Verbal memory declined in 2 of 8 MHT- and 1 of 6 MHT+ patients, and visual memory declined in 1 of 8 MHT- and 2 of 6 MHT+ patients. Two patients had improved visual memory postoperatively, both in the MHT+ group. CONCLUSION: MHT on the dominant side is associated with high rates of seizure freedom and favorable memory preservation outcomes regardless of the extent of neocortical resection. Preservation of the temporal neocortex and amygdala during MHT does not appear to decrease the risk of postoperative memory decline, nor does it alter seizure outcome.

Treatment options for posttraumatic epilepsy.

PURPOSE OF REVIEW: Posttraumatic seizures (PTS) and posttraumatic epilepsy (PTE) are common and debilitating consequences of traumatic brain injury (TBI). Early PTS result in secondary brain injury by raising intracranial pressure and worsening cerebral edema and metabolic crisis. PTE is a localization-related epilepsy strongly associated with TBI severity, but risk factors for PTE and epileptogenesis are incompletely understood and are active areas of research. Medical management of PTS in adults and children is reviewed. Surgical options for posttraumatic drug-resistant epilepsy are also discussed. RECENT FINDINGS: Continuous electroencephalography is indicated for children and adults with TBI and coma because of the high incidence of nonconvulsive seizures, periodic discharges, and associated secondary brain injury in this population. Neuroinflammation is a central component of secondary brain injury and appears to play a key role in epileptogenesis. Levetiracetam is increasingly used for seizure prophylaxis in adults and children, but variability remains. SUMMARY: PTS occur commonly after TBI and are associated with secondary brain injury and worse outcomes in adults and children. Current medical and surgical management options for PTS and PTE are reviewed.

Effect of Stereoscopic Anaglyphic 3-Dimensional Video Didactics on Learning Neuroanatomy.

BACKGROUND: The teaching of neuroanatomy in medical education has historically been based on didactic instruction, cadaveric dissections, and intraoperative experience for students. Multiple novel 3-dimensional (3D) modalities have recently emerged. Among these, stereoscopic anaglyphic video is easily accessible and affordable, however, its effects have not yet formally been investigated. OBJECTIVE: This study aimed to investigate if 3D stereoscopic anaglyphic video instruction in neuroanatomy could improve learning for content-naive students, as compared with 2-dimensional (2D) video instruction. METHODS: A single-site controlled prospective case control study was conducted at the School of Education. Content knowledge was assessed at baseline, followed by the presentation of an instructional neuroanatomy video. Participants viewed the video in either 2D or 3D format and then completed a written test of skull base neuroanatomy. Pretest and post-test performances were analyzed with independent Student's t-tests and analysis of covariance. RESULTS: Our study was completed by 249 subjects. At baseline, the 2D (n = 124, F = 97) and 3D groups (n = 125, F = 96) were similar, although the 3D group was older by 1.7 years (P = 0.0355) and the curricula of participating classes differed (P < 0.0001). Average scores for the 3D group were higher for both pretest (2D, M = 19.9%, standard deviation [SD] = 12.5% vs. 3D, M = 23.9%, SD = 14.9%, P = 0.0234) and post-test performances (2D, M = 68.5%, SD = 18.6% vs. 3D, M = 77.3%, SD = 18.8%, P = 0.003), but the magnitude of improvement across groups did not reach statistical significance (2D, M = 48.7%, SD = 21.3%, vs. 3D, M = 53.5%, SD = 22.7%, P = 0.0855). CONCLUSION: Incorporation of 3D video instruction into curricula without careful integration is insufficient to promote learning over 2D video.