The Sensitivity of Limited-Sequence MRI in Identifying Pediatric Cervical Spine Injury: A Western Pediatric Surgery Research Consortium Multicenter Retrospective Cohort Study.

INTRODUCTION: Clinical clearance of a child's cervical spine after trauma is often challenging due to impaired mental status or an unreliable neurologic examination. Magnetic resonance imaging (MRI) is the gold standard for excluding ligamentous injury in children but is constrained by long image acquisition times and frequent need for anesthesia. Limited-sequence MRI (LSMRI) is used in evaluating the evolution of traumatic brain injury and may also be useful for cervical spine clearance while potentially avoiding the need for anesthesia. The purpose of this study was to assess the sensitivity and negative predictive value of LSMRI as compared to gold standard full-sequence MRI as a screening tool to rule out clinically significant ligamentous cervical spine injury. METHODS: We conducted a ten-center, five-year retrospective cohort study (2017-2021) of all children (0-18y) with a cervical spine MRI after blunt trauma. MRI images were re-reviewed by a study pediatric radiologist at each site to determine if the presence of an injury could be identified on limited sequences alone. Unstable cervical spine injury was determined by study neurosurgeon review at each site. RESULTS: We identified 2,663 children less than 18 years of age who underwent an MRI of the cervical spine with 1,008 injuries detected on full-sequence studies. The sensitivity and negative predictive value of LSMRI were both >99% for detecting any injury and 100% for detecting any unstable injury. Young children (age < 5 years) were more likely to be electively intubated or sedated for cervical spine MRI. CONCLUSION: LSMRI is reliably detects clinically significant ligamentous injury in children after blunt trauma. To decrease anesthesia use and minimize MRI time, trauma centers should develop LSMRI screening protocols for children without a reliable neurologic exam. LEVEL OF EVIDENCE: 2 (Diagnostic Tests or Criteria).

Long-term outcomes of mesial temporal laser interstitial thermal therapy for drug-resistant epilepsy and subsequent surgery for seizure recurrence: a multi-centre cohort study.

BACKGROUND: Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive alternative to surgical resection for drug-resistant mesial temporal lobe epilepsy (mTLE). Reported rates of seizure freedom are variable and long-term durability is largely unproven. Anterior temporal lobectomy (ATL) remains an option for patients with MRgLITT treatment failure. However, the safety and efficacy of this staged strategy is unknown. METHODS: This multicentre, retrospective cohort study included 268 patients consecutively treated with mesial temporal MRgLITT at 11 centres between 2012 and 2018. Seizure outcomes and complications of MRgLITT and any subsequent surgery are reported. Predictive value of preoperative variables for seizure outcome was assessed. RESULTS: Engel I seizure freedom was achieved in 55.8% (149/267) at 1 year, 52.5% (126/240) at 2 years and 49.3% (132/268) at the last follow-up ≥1 year (median 47 months). Engel I or II outcomes were achieved in 74.2% (198/267) at 1 year, 75.0% (180/240) at 2 years and 66.0% (177/268) at the last follow-up. Preoperative focal to bilateral tonic-clonic seizures were independently associated with seizure recurrence. Among patients with seizure recurrence, 14/21 (66.7%) became seizure-free after subsequent ATL and 5/10 (50%) after repeat MRgLITT at last follow-up≥1 year. CONCLUSIONS: MRgLITT is a viable treatment with durable outcomes for patients with drug-resistant mTLE evaluated at a comprehensive epilepsy centre. Although seizure freedom rates were lower than reported with ATL, this series represents the early experience of each centre and a heterogeneous cohort. ATL remains a safe and effective treatment for well-selected patients who fail MRgLITT.

Bacterial Brain Abscess and Life-Threatening Intracranial Hypertension Requiring Emergent Decompressive Craniectomy After SARS-CoV-2 Infection in a Healthy Adolescent.

Acute coronavirus 2 (SARS-CoV-2) infection usually results in mild symptoms, but secondary infections after SARS-CoV-2 infection can occur, particularly with comorbid conditions. We present the clinical course of a healthy adolescent with a brain abscess and life-threatening intracranial hypertension requiring emergent decompressive craniectomy after a SARS-CoV-2 infection. A 13-year-old healthy immunized male presented with invasive frontal, ethmoid, and maxillary sinusitis and symptoms of lethargy, nausea, headache, and photophobia due to a frontal brain abscess diagnosed three weeks after symptoms and 11 days of oral amoxicillin treatment. Coronavirus disease 2019 (COVID-19) reverse transcription-polymerase chain reaction (RT-PCR) was negative twice but then positive on amoxicillin day 11 (symptom day 21), when magnetic resonance imaging revealed a 2.5-cm right frontal brain abscess with a 10-mm midline shift. The patient underwent emergent craniotomy for right frontal epidural abscess washout and functional endoscopic sinus surgery with ethmoidectomy. On a postoperative day one, his neurological condition showed new right-sided pupillary dilation and decreased responsiveness. His vital signs showed bradycardia and systolic hypertension. He underwent an emergent decompressive craniectomy for signs of brain herniation. Bacterial PCR was positive for Streptococcus intermedius, for which he received intravenous vancomycin and metronidazole. He was discharged home on hospital day 14 without neurological sequelae and future bone flap replacement. Our case highlights the importance of timely recognition and treatment of brain abscess and brain herniation in patients with neurological symptoms after SARS-CoV-2 infection, even in otherwise healthy patients.

Ultra-low-level measurements of airborne fission products from the Fukushima Daiichi reactor accident using high volume collection systems at Savannah River National Laboratory.

Ultra-low-level measurements of radionuclides in air have been conducted at the Savannah River National Laboratory (SRNL) to determine the atmospheric concentration of fission products released following the Fukushima Daiichi reactor accident on March 11, 2011. Air filter samples were acquired from two high-volume collection systems (a traditional filter-based system and an electrostatic precipitator-based system) to monitor airborne radionuclide concentrations in the period covering from 2 weeks to 3 years after the disaster. The world-wide spread of low-level concentrations of airborne fission products from the Fukushima event provided a unique opportunity to demonstrate SRNL's electrostatic particle collection technology and other improvements in environmental monitoring developed at the Savannah River Site (SRS). Detecting and analyzing the release allowed a comprehensive test of SRS systems for monitoring environmental radioactivity. Gamma-ray-emitting fission products (131,132I, 134,136,137Cs, and 129,132Te) and cosmogenic isotopes (7Be and 22Na) in air were detected and quantified by high-resolution gamma-ray spectroscopy at concentrations as low as 0.07 µBq per standard cubic meter (SCM) (50 mBq total 137Cs), while plutonium content was quantified by thermal ionization mass spectrometry (TIMS) at concentrations as low as 6.5 × 10-21 g/SCM (3.0 fg 239+240Pu). Isotope concentrations measured at SRNL from gamma-ray spectroscopy were compared to independent measurements from Chapel Hill, NC, located approximately 370 km (230 mi) NE of SRNL. Meteorological modeling was also used to predict radionuclide transport from the location of release to both measurement locations.

A clinically applicable functional MRI memory paradigm for use with pediatric patients.

OBJECTIVE: Clinically employable functional MRI (fMRI) memory paradigms are not yet established for pediatric patient epilepsy surgery workups. Seeking to establish such a paradigm, we evaluated the effectiveness of memory fMRI tasks we developed by quantifying individual activation in a clinical pediatric setting, analyzing patterns of activation relative to the side of temporal lobe (TL) pathology, and comparing fMRI and Wada test results. METHODS: We retrospectively identified 72 patients aged 6.7-20.9 years with pathology (seizure focus and/or tumor) limited to the TL who had attempted memory and language fMRI tasks over a 9-year period as part of presurgical workups. Memory fMRI tasks required visualization of autobiographical memories in a block design alternating with covert counting. Language fMRI protocols involved verb and sentence generation. Scans were both qualitatively interpreted and quantitatively assessed for blood oxygenation level dependent (BOLD) signal change using region of interest (ROI) masks. We calculated the percentage of successfully scanned individual cases, compared 2 memory task activation masks in cases with left versus right TL pathology, and compared fMRI with Wada tests when available. Patients who had viable fMRI and Wada tests had generally concordant results. RESULTS: Of the 72 cases, 60 (83%), aged 7.6-20.9 years, successfully performed the memory fMRI tasks and 12 (17%) failed. Eleven of 12 unsuccessful scans were due to motion and/or inability to perform the tasks, and the success of a twelfth was indeterminate due to orthodontic metal artifact. Seven of the successful 60 cases had distorted anatomy that precluded employing predetermined masks for quantitative analysis. Successful fMRI memory studies showed bilateral mesial temporal activation and quantitatively demonstrated: (1) left activation (L-ACT) less than right activation (R-ACT) in cases with left temporal lobe (L-TL) pathology, (2) nonsignificant R-ACT less than L-ACT in cases with right temporal lobe (R-TL) pathology, and (3) lower L-ACT plus R-ACT activation for cases with L-TL versus R-TL pathology. Patients who had viable fMRI and Wada tests had generally concordant results. SIGNIFICANCE: This study demonstrates evidence of an fMRI memory task paradigm that elicits reliable activation at the individual level and can generally be accomplished in clinically involved pediatric patients. This autobiographical memory paradigm showed activation in mesial TL structures, and cases with left compared to right TL pathology showed differences in activation consistent with extant literature in TL epilepsy. Further studies will be required to assess outcome prediction.

Pediatric hemispherectomy outcome: Adaptive functioning, intelligence, and memory.

OBJECTIVE: Our purpose was to characterize neuropsychological evaluation (NP) outcome following functional hemispherectomy in a large, representative cohort of pediatric patients. METHODS: We evaluated seizure and NP outcomes and medical variables for all post-hemispherectomy patients from Seattle Children's Hospital epilepsy surgery program between 1996 and 2020. Neuropsychological evaluation outcome tests used were not available on all patients due to the diversity of patient ages and competency that is typical of a representative pediatric cohort; all patients had at least an adaptive functioning or intelligence measure, and a subgroup had memory testing. RESULTS: A total of 71 hemispherectomy patients (37 right; 34 females) yielded 66 with both preoperative (PREOP) plus postoperative (POSTOP) NPs and 5 with POSTOP only. Median surgery age was 5.7 (IQR 2-9.9) years. Engel classification indicated excellent seizure outcomes: 59 (84%) Class I, 6 (8%) Class II, 5 (7%) Class III, and 1 (1%) Class IV. Medical variables - including seizure etiology, surgery age, side, presurgical seizure duration, unilateral or bilateral structural abnormalities, secondarily generalized motor seizures - were not associated with either Engel class or POSTOP NP scores, though considerable heterogeneity was evident. Median PREOP and POSTOP adaptive functioning (PREOP n = 45, POSTOP n = 48) and intelligence (PREOP n = 29, POSTOP n = 36) summary scores were exceptionally low and did not reveal group decline from PREOP to POSTOP. Fifty-five of 66 (85%) cases showed stability or improvement. Specifically, 5 (8%) improved; 50 (76%) showed stability; and 11 (16%) declined. Improve and decline groups showed clinically interesting, but not statistical, differences in seizure control and age. Median memory summary scores were low and also showed considerable heterogeneity. Overall median PREOP to POSTOP memory scores (PREOP n = 16, POSTOP n = 24) did not reveal declines, and verbal memory scores improved. Twenty six percent of intelligence and 33% of memory tests had verbal versus visual-spatial discrepancies; all but one favored verbal, regardless of hemispherectomy side. SIGNIFICANCE: This large, single institution study revealed excellent seizure outcome in 91% of all 71 patients plus stability and/or improvement of intelligence and adaptive functioning in 85% of 66 patients who had PREOP plus POSTOP NPs. Memory was similarly stable overall, and verbal memory improved. Medical variables did not predict group NP outcomes though heterogeneity argues for further research. This study is unique for cohort size, intelligence plus memory testing, and evidence of primacy of verbal over visual-spatial development, despite hemispherectomy side. This study reinforces the role of hemispherectomy in achieving good seizure outcome while preserving functioning.

Targeting the World's Slums as Fat Tails in the Distribution of COVID-19 Cases.

A recent article by Corburn et al. lays out the policies that would help slum communities in the global south deal with COVID-19. That article notes the vulnerabilities of people in these informal settlements and argues that any assistance program must recognize these realities so that the policies do not further jeopardize the survival of large segments of the population of these communities. This note extends the arguments in that paper, focusing on some of the logistic issues involved in providing assistance to informal settlements. It argues that such assistance is essential not only for the help it would provide to people in these settlements but also because the residents of these communities should be key targets of assistance. Because of the location and occupation of most of the residents of these communities, targeting them simultaneously addresses health and economy-wide concerns generated by COVID-19. Their characteristics make them much more likely to be afflicted by the virus and spread it to others. The main conclusions of this note with respect to policy are that the scale of such assistance is likely to be larger than has so far been proposed, that in countries with limited testing ability slums provide one of the most effective places to target assistance, that the role of community groups in providing the assistance is difficult to exaggerate, and that philanthropy has a role to play in supporting innovation.

Laser interstitial thermal therapy for pediatric atypical teratoid/rhabdoid tumor: case report.

Herein, the authors describe the successful use of laser interstitial thermal therapy (LITT) for management of metastatic craniospinal disease for biopsy-proven atypical teratoid/rhabdoid tumor in a 16-month-old boy presenting to their care. Specifically, LITT was administered to lesions of the right insula and left caudate. The patient tolerated 2 stages of LITT to the aforementioned lesions without complication and with evidence of radiographic improvement of lesions at the 2- and 6-month follow-up appointments. To the authors' knowledge, this represents the first such published report of LITT for management of atypical teratoid/rhabdoid tumor.

Uniformed Medical Students and Residents in Emergency Medicine.

"Uniformed medical students and residents" refers to medical school enrollees and physicians in training who are obligated to serve in the military after graduation or training completion. This is in exchange for 2 forms of financial support that are provided by the military for individuals interested in pursuing a career in medicine. These programs are offered namely through the Uniformed Services University of Health Sciences (USUHS) and the Health Professions Scholarship Program (HPSP). Uniformed medical school graduates can choose to serve with the military upon graduation or to pursue residency training. Residency can be completed at in-service programs at military treatment facilities, at out-service programs, at civilian residency training programs, or via deferment programs for residency training at civilian programs. Once their residency training is completed, military physicians should then complete their service obligation. As such, both USUHS and HPSP students should attend a basic officer training to ensure their preparedness for military service. In this article, we elaborate more on the mission, requirements, application, and benefits of both USUHS and HPSP. Moreover, we expand on the officer preparedness training, postgraduate education in the military, unique opportunities of military medicine, and life after completion of military obligation.

Standard Free Versus Osteoplastic Craniotomy: Assessment of Complication Rates During Intracranial Electroencephalogram Electrode Placement for Seizure Localization.

OBJECTIVE: Patients with medically intractable epilepsy often undergo sequential surgeries and are therefore exposed to an elevated risk for infection, resulting in unanticipated returns to the operating room. The goal of our study was to determine whether use of an osteoplastic bone flap technique would reduce the infection rate in these patients. METHODS: A single-institution, retrospective chart review of patients with medically intractable epilepsy for grid placement was performed. Univariate analyses and linear regression were used to assess primary outcomes, including infection and hematomas requiring surgical evacuation. Secondary outcomes included duration of treatment and other, unanticipated surgeries. RESULTS: A total of 199 patients were identified, 56 (28%) with osteoplastic flaps. Standard free flaps were associated with an increased rate of infection at the craniotomy site (n = 24, 17%, vs. 0, 0%, P = 0.003), whereas osteoplastic flaps were associated with more returns to operating room for hematoma evacuation (n = 5, 9% vs. 3.2%, P = 0.024). Overall, the rate of return to operating room for unanticipated surgeries was similar, but infectious complications prolonged the duration of treatment (median: 17 days vs. 2 days, χ2 = 13.97, P < 0.001). CONCLUSIONS: Osteoplastic bone flaps markedly decreased the risk of craniotomy infections compared with free flaps in patients undergoing sequential surgeries. This decrease is offset, however, by an increase in intracranial hematoma requiring return to the operating room. Infection appeared to be a more significant complication as it was associated with increased duration of treatment. The osteoplastic technique is especially appealing in those patients likely to undergo multiple surgeries in short succession.

Reversible, Position-Dependent Midbrain Compression in a Patient with Spontaneous Intracranial Hypotension.

BACKGROUND: Intracranial hypotension is an underrecognized cause of spontaneous subdural hematoma. Failure to identify this entity and treat the underlying etiology can result in profoundly dangerous clinical consequences, prolonged and costly hospitalization, and caregiver fatigue, as seen in the case presented here. CASE DESCRIPTION: We present a case of intracranial hypotension associated with a spontaneous cerebrospinal fluid (CSF) leak in the cervical spine leading to consistently reproducible herniation syndrome with head of bed elevation, and bilateral subdural hematomas as a result of a pressure gradient favoring downward migration of intracranial contents resulting in traction on bridging veins. This gradient promoted transtentorial herniation with resultant brainstem compression, leading to a prolonged intensive care unit stay, recurrent respiratory failure, and severe deconditioning. An exhaustive diagnostic workup uncovered a cervical root CSF leak with a nuclear medicine CSF flow study, which was successfully treated with nerve root ligation and dural closure. The patient recovered well postprocedurally and was able to return to baseline level of function. CONCLUSIONS: This case demonstrates the importance of considering intracranial hypotension in cases of positional herniation syndrome and the necessity for early and aggressive attempts at identifying and treating the underlying cause to prevent unnecessary neurologic dysfunction and protracted medical care.

Primary External Ventricular Drainage Catheter Versus Intraparenchymal ICP Monitoring: Outcome Analysis.

BACKGROUND: Intracranial pressure (ICP) monitoring is central to the care of severe traumatic brain injury (TBI). External ventricular drains (EVD) allow ICP control via cerebrospinal fluid drainage, whereas intraparenchymal monitors (IPM) for ICP do not, but it is unclear whether EVD placement improves outcomes. To evaluate whether there exists a difference in patient outcomes with the use of EVD versus IPM in severe TBI patients, we conducted a retrospective cohort study using data from the Citicoline Brain Injury Treatment trial. METHODS: Adults with Glasgow Coma Score < 9 who had either an EVD or IPM placed within 6 h of study center arrival were included. We compared patients with EVD placement to those without on Glasgow Outcome Scale-Extended (GOS-E) and neuropsychological performance at 180 days, mortality, and intensive care unit length of stay. We used regression models with propensity score weighting for probability of EVD placement to test for association between EVD use and outcomes. Of 224 patients included, 45% received an EVD. RESULTS: EVD patients had lower GOS-E at 180 days [3.8 ± 2.2 vs 4.9 ± 2.2, p = 0.002; weighted difference - 0.97, 95% CI (- 1.58, - 0.37)], higher in-hospital mortality [23% vs 10%, p = 0.014; weighted OR 2.46, 95% CI (1.20, 5.05)], and did significantly worse on all 8 neuropsychological measures. Additional sensitivity analysis was performed to minimize confounding effects supported our initial results. CONCLUSIONS: Our retrospective data analysis suggests that early placement of EVDs in severe TBI is associated with worse functional and neuropsychological outcomes and higher mortality than IPMs and future prospective trials are needed to determine whether these results represent an important consideration for clinicians.

Effects of surgical targeting in laser interstitial thermal therapy for mesial temporal lobe epilepsy: A multicenter study of 234 patients.

OBJECTIVE: Laser interstitial thermal therapy (LITT) for mesial temporal lobe epilepsy (mTLE) has reported seizure freedom rates between 36% and 78% with at least 1 year of follow-up. Unfortunately, the lack of robust methods capable of incorporating the inherent variability of patient anatomy, the variability of the ablated volumes, and clinical outcomes have limited three-dimensional quantitative analysis of surgical targeting and its impact on seizure outcomes. We therefore aimed to leverage a novel image-based methodology for normalizing surgical therapies across a large multicenter cohort to quantify the effects of surgical targeting on seizure outcomes in LITT for mTLE. METHODS: This multicenter, retrospective cohort study included 234 patients from 11 centers who underwent LITT for mTLE. To investigate therapy location, all ablation cavities were manually traced on postoperative magnetic resonance imaging (MRI), which were subsequently nonlinearly normalized to a common atlas space. The association of clinical variables and ablation location to seizure outcome was calculated using multivariate regression and Bayesian models, respectively. RESULTS: Ablations including more anterior, medial, and inferior temporal lobe structures, which involved greater amygdalar volume, were more likely to be associated with Engel class I outcomes. At both 1 and 2 years after LITT, 58.0% achieved Engel I outcomes. A history of bilateral tonic-clonic seizures decreased chances of Engel I outcome. Radiographic hippocampal sclerosis was not associated with seizure outcome. SIGNIFICANCE: LITT is a viable treatment for mTLE in patients who have been properly evaluated at a comprehensive epilepsy center. Consideration of surgical factors is imperative to the complete assessment of LITT. Based on our model, ablations must prioritize the amygdala and also include the hippocampal head, parahippocampal gyrus, and rhinal cortices to maximize chances of seizure freedom. Extending the ablation posteriorly has diminishing returns. Further work is necessary to refine this analysis and define the minimal zone of ablation necessary for seizure control.

The Sustainable Development Goal for Urban Sanitation: Africa's Statistical Tragedy Continues?

Sanitation delivery in the urban areas of sub-Saharan African countries has been a chronic issue, particularly difficult to tackle. Under the Millennium Development Goals, the sanitation target in urban sub-Saharan Africa was missed by a wide margin and witnessed almost no improvement. After 2 years of review, the WHO/UNICEF Joint Monitoring Programme published a new measure of access to sanitation as a baseline for the Sustainable Development Goals. There are a number of improvements in the new measure. However, despite the improvements, the new measure continues to be characterized by an important flaw: it continues to disregard how shared toilet facilities contribute towards the SDG sanitation target. As a result, the new measure does not indicate whether progress is being made in low-income urban areas where a large number of households rely on shared sanitation; nor does it provide a goal that can be achieved in cities of the poorest countries over the measurement period. But, its most egregious failing is that it directs resources towards investments which will often fail cost/benefit tests. In sum, it is not a surprise that a Working Group recommended that the measure should be changed to include some shared facilities. Following the Working Group's recommendation would have avoided the adverse consequences of continued reliance on a key component of the methodology used for monitoring sanitation improvements under the Millennium Development Goals. The paper discusses the limitations of this methodology in the context of urban sub-Saharan Africa, where current sanitation conditions are seriously lacking, and the significant future urban population growth will add more pressure for the delivery of vital sanitation services.

Corticospinal tract atrophy and motor fMRI predict motor preservation after functional cerebral hemispherectomy.

OBJECTIVE The potential loss of motor function after cerebral hemispherectomy is a common cause of anguish for patients, their families, and their physicians. The deficits these patients face are individually unique, but as a whole they provide a framework to understand the mechanisms underlying cortical reorganization of motor function. This study investigated whether preoperative functional MRI (fMRI) and diffusion tensor imaging (DTI) could predict the postoperative preservation of hand motor function. METHODS Thirteen independent reviewers analyzed sensorimotor fMRI and colored fractional anisotropy (CoFA)-DTI maps in 25 patients undergoing functional hemispherectomy for treatment of intractable seizures. Pre- and postoperative gross hand motor function were categorized and correlated with fMRI and DTI findings, specifically, abnormally located motor activation on fMRI and corticospinal tract atrophy on DTI. RESULTS Normal sensorimotor cortical activation on preoperative fMRI was significantly associated with severe decline in postoperative motor function, demonstrating 92.9% sensitivity (95% CI 0.661-0.998) and 100% specificity (95% CI 0.715-1.00). Bilaterally robust, symmetric corticospinal tracts on CoFA-DTI maps were significantly associated with severe postoperative motor decline, demonstrating 85.7% sensitivity (95% CI 0.572-0.982) and 100% specificity (95% CI 0.715-1.00). Interpreting the fMR images, the reviewers achieved a Fleiss' kappa coefficient (κ) for interrater agreement of κ = 0.69, indicating good agreement (p < 0.01). When interpreting the CoFA-DTI maps, the reviewers achieved κ = 0.64, again indicating good agreement (p < 0.01). CONCLUSIONS Functional hemispherectomy offers a high potential for seizure freedom without debilitating functional deficits in certain instances. Patients likely to retain preoperative motor function can be identified prior to hemispherectomy, where fMRI or DTI suggests that cortical reorganization of motor function has occurred prior to the operation.

Characterizing the detectability of emission signals from a North Korean nuclear detonation.

The detectability of emission sources, defined by a low-level of mixing with other sources, was estimated for various locations surrounding the Sea of Japan, including a site within North Korea. A high-resolution meteorological model coupled to a dispersion model was used to simulate plume dynamics for four periods, and two metrics of airborne plume mixing were calculated for each source. While emissions from several known sources in this area tended to blend with others while dispersing downwind, the North Korean plume often remained relatively distinct, thereby making it potentially easier to unambiguously 'backtrack' it to its source.

Stereotactic laser ablation for hypothalamic and deep intraventricular lesions.

OBJECTIVE Laser ablation is a novel, minimally invasive procedure that utilizes MRI-guided thermal energy to treat epileptogenic and other brain lesions. In addition to treatment of mesial temporal lobe epilepsy, laser ablation is increasingly being used to target deep or inoperable lesions, including hypothalamic hamartoma (HH), subependymal giant cell astrocytoma (SEGA), and exophytic intrinsic hypothalamic/third ventricular tumors. The authors reviewed their early institutional experience with these patients to characterize clinical outcomes in patients undergoing this procedure. METHODS A retrospective cohort (n = 12) of patients undergoing laser ablation at a single institution was identified, and clinical and radiographic records were reviewed. RESULTS Laser ablation was successfully performed in all patients. No permanent neurological or endocrine complications occurred; 2 (17%) patients developed acute obstructive hydrocephalus or shunt malfunction following treatment. Laser ablation of HH resulted in seizure freedom (Engel Class I) in 67%, with the remaining patients having a clinically significant reduction in seizure frequency of greater than 90% compared with preoperative baseline (Engel Class IIB). Treatment of SEGAs resulted in durable clinical and radiographic tumor control in 2 of 3 cases, with one patient receiving adjuvant everolimus and the other receiving no additional therapy. Palliative ablation of hypothalamic/third ventricular tumors resulted in partial tumor control in 1 of 3 patients. CONCLUSIONS Early experience suggests that laser ablation is a generally safe, durable, and effective treatment for patients harboring HHs. It also appears effective for local control of SEGAs, especially in combination therapy with everolimus. Its use as a palliative treatment for intrinsic hypothalamic/deep intraventricular tumors was less successful and associated with a higher risk of serious complications. Additional experience and long-term follow-up will be beneficial in further characterizing the effectiveness and risk profile of laser ablation in treating these lesions in comparison with conventional resective surgery or stereotactic radiosurgery.

Laser Ablation in Pediatric Epilepsy.

Laser ablation is an emerging, minimally invasive treatment for selected children with intractable focal epilepsy with improved procedural morbidity. Data for children lag similar studies in adults, but the hope is for near-equivalent seizure-control rates and improved neuropsychological outcome when compared with standard open surgical resection. The approach seems particularly beneficial when dealing with deep, focal lesions, such as hypothalamic hamartomas or hippocampal sclerosis.

The safety of vasopressor-induced hypertension in subarachnoid hemorrhage patients with coexisting unruptured, unprotected intracranial aneurysms.

OBJECT: Vasopressor-induced hypertension (VIH) is an established treatment for patients with aneurysmal subarachnoid hemorrhage (SAH) who develop vasospasm and delayed cerebral ischemia (DCI). However, the safety of VIH in patients with coincident, unruptured, unprotected intracranial aneurysms is uncertain. METHODS: This retrospective multiinstitutional study identified 1) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who required VIH therapy (VIH group), and 2) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who did not require VIH therapy (non-VIH group). All patients had previously undergone surgical or endovascular treatment for the presumed ruptured aneurysm. Comparisons between the VIH and non-VIH patients were made in terms of the patient characteristics, clinical and radiographic severity of SAH, total number of aneurysms, number of ruptured/unruptured aneurysms, aneurysm location/size, number of unruptured and unprotected aneurysms during VIH, severity of vasospasm, degree of hypervolemia, and degree and duration of VIH therapy. RESULTS: For the VIH group (n = 176), 484 aneurysms were diagnosed, 231 aneurysms were treated, and 253 unruptured aneurysms were left unprotected during 1293 total days of VIH therapy (5.12 total years of VIH therapy for unruptured, unprotected aneurysms). For the non-VIH group (n = 73), 207 aneurysms were diagnosed, 93 aneurysms were treated, and 114 unruptured aneurysms were left unprotected. For the VIH and non-VIH groups, the mean sizes of the ruptured (7.2 ± 0.3 vs 7.8 ± 0.6 mm, respectively; p = 0.27) and unruptured (3.4 ± 0.2 vs 3.2 ± 0.2 mm, respectively; p = 0.40) aneurysms did not differ. The authors observed 1 new SAH from a previously unruptured, unprotected aneurysm in each group (1 of 176 vs 1 of 73 patients; p = 0.50). Baseline patient characteristics and comorbidities were similar between groups. While the degree of hypervolemia was similar between the VIH and non-VIH patients (fluid balance over the first 10 days of therapy: 3146.2 ± 296.4 vs 2910.5 ± 450.7 ml, respectively; p = 0.67), VIH resulted in a significant increase in mean arterial pressure (mean increase over the first 10 days of therapy relative to baseline: 125.1% ± 1.0% vs 98.2% ± 1.2%, respectively; p < 0.01) and systolic blood pressure (125.6% ± 1.1% vs. 104.1% ± 5.2%, respectively; p < 0.01). CONCLUSIONS: For small, unruptured, unprotected intracranial aneurysms in SAH patients, the frequency of aneurysm rupture during VIH therapy is rare. The authors do not recommend withholding VIH therapy from these patients.

Recurrent Supplementary Motor Area Syndrome Following Repeat Brain Tumor Resection Involving Supplementary Motor Cortex.

BACKGROUND: Supplementary motor area (SMA) syndrome occurs after surgery involving the SMA and is characterized by contralateral hemiparesis with or without speech impairment (dependent on involvement of the dominant SMA), which is transient and characteristically resolves over the course of weeks to months. Recurrent SMA syndrome after repeat craniotomy has not been previously described. OBJECTIVE: To describe the presentation and clinical course of patients who developed recurrent SMA syndrome after redo resection of tumors involving the SMA. METHODS: We performed a retrospective review of 15 patients who underwent repeated resection of low-grade glioma from the superior and middle frontal gyrus. Of these patients, we identified 6 cases of recurrent SMA syndrome. RESULTS: Six patients had a documented SMA syndrome occurring after initial and subsequent resection of tumor in proximity to the SMA. Intraoperative localization of eloquent motor and language cortex was achieved in each patient by using a combination of somatosensory evoked potentials and electrocortical stimulation mapping. Location of tumor and extent of resection was examined with magnetic resonance imaging. CONCLUSION: This series demonstrates that recurrent SMA syndrome occurs in patients undergoing repeat resection of tumors involving the SMA. The presence of recurrent SMA syndrome provides support for reorganization of SMA function to adjacent ipsilateral cortex after resection. Patients with recurrent neoplasms of the SMA should be counseled on the possibility of recurrent SMA syndrome.