Non-staged bilateral Globus Pallidus Internus deep brain stimulation lead revision using intraoperative MRI: a case report and literature review.

BACKGROUND: Deep brain stimulation (DBS) lead revision due to suboptimal therapy is common but there is no standardised protocol. We describe a novel technique using iMRI to perform concurrent new Globus Pallidus Internus (GPi) DBS lead implantation and old lead removal in a dystonia patient.Case-description: A 60-year-old woman with medication and neurotoxin-refractory isolated cervical dystonia underwent awake bilateral GPi DBS surgery with MER-guided lead implantation. She initially had a favourable response but later reported suboptimal benefit despite reprogramming. MRI demonstrated suboptimal lead placement and MRI-guided revision surgery under general anesthesia was planned. The goal was to place new leads superior and medial to the existing leads. Using a 1.5 T iMRI and the ClearPoint® NeuroNavigation system, new leads were placed through the existing burr holes, into the new targets with radial errors < 0.08mm bilaterally without crossing the old leads. The old leads were then removed and the new leads connected to the existing pulse generator. The patient tolerated the procedure well and had improved side-effect profile at all contacts at 1-month follow-up. CONCLUSIONS: Non-staged iMRI-guided DBS revision surgery under general anesthesia is technically feasible and is an alternative strategy to a staged iMRI-guided revision surgery or an awake MER-guided revision surgery in select patients.

Odor identification predicts postoperative seizure control following magnetic resonance-guided laser interstitial thermal therapy.

OBJECTIVE: Olfactory dysfunction has been well documented in individuals with temporal lobe epilepsy, but its use in presurgical planning has yet to be examined. We assessed the role of preoperative odor identification in mesial onset seizure localization utilizing stereoelectroencephalography (S-EEG) and magnetic resonance-guided laser interstitial thermal therapy (MRgLiTT) outcome. METHODS: We identified 30 patients who had typical seizures captured during S-EEG monitoring or MRgLiTT of mesial temporal structures (n = 17 S-EEG, n = 13 MRgLiTT); seizure onset zone was classified as unilateral mesial seizure onset, or multifocal with unilateral mesial onset and nonmesial onset. Odor identification ability was assessed using the Sniffin' Sticks Odor Identification Test (SSOIT). Patients also completed measures of confrontation naming and auditory-verbal learning/memory using the Boston Naming Test and Hopkins Verbal Learning Test-Revised, respectively. RESULTS: Overall, patients with intractable focal epilepsy exhibited poor olfactory performance (median [M] = 10.4, interquartile range [IQR] = 9.4-11.8). Of 19 patients who underwent MRgLiTT, 10 patients (52.6%) were seizure-free at last follow-up (M = 13 months, IQR =10-18). Patients who were seizure-free after MRgLiTT (n = 10) had poorer odor identification scores (M = 9, IQR = 7-13) compared to patients with seizure reoccurrence (M = 13, IQR = 12.5-15). Odor identification score was inversely associated with seizure freedom, with odds ratio = 0.60 (95% confidence interval [CI] = 0.38-0.95, P = .03). Receiver operating characteristic analysis revealed that an SSOIT score of 12 was the ideal cutoff for predicting favorable seizure outcome (area under the curve = 0.84, 95% CI = 0.64-1.0). Sensitivity was 88.9% and specificity was 78.9%, with a likelihood ratio of 2.9 of seizure failure in patients who had an odor identification score ≥ 12. SIGNIFICANCE: Interictal olfactory dysfunction is commonly seen in patients with intractable focal epilepsy. Odor identification is a novel, noninvasive presurgical biomarker to distinguish who may or may not benefit from MRgLiTT of mesial temporal structures.

Olfactory Testing in Temporal Lobe Epilepsy: a Systematic Review.

PURPOSE OF REVIEW: Olfactory testing is a potentially safe, cost-effective, bedside evaluation tool for diagnosis, monitoring, and risk assessment for surgery in temporal lobe epilepsy (TLE) patients, but testing methods and relevant olfactory domains are not standardized. We conducted a systematic review to evaluate olfactory tests in TLE and summarize the results of the literature. RECENT FINDINGS: Olfactory tests varied significantly in odorant administration tools and devices, target odorants, evaluation timing, and grading scales. The Smell Threshold Test and University of Pennsylvania Smell Identification Test were the most validated single-domain tests for odor detection and odor identification, respectively. For multi-domain tests, Odor Memory/Discrimination Test and the Sniffin' Sticks test were the most validated. Results of olfactory tests in TLE are presented by domain. Rigorous validation, standardization, and comparative analysis of existing olfactory tests by domain is urgently needed to establish the utility and efficacy of olfactory testing in TLE.

Glioblastoma biomarkers from bench to bedside: advances and challenges.

Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumour, with few available therapies providing significant improvements in mortality. Biomarkers, which are defined by the National Institutes of Health as 'characteristics that are objectively measured and evaluated as indicators of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention', have the potential to play valuable roles in the diagnosis and treatment of GBM. Although GBM biomarker research is still in its early stages because of the tumour's complex pathophysiology, a number of potential markers have been identified which can be measured in either brain tissue or blood serum. In conjunction with other clinical data, particularly neuroimaging modalities such as MRI, these proteins could contribute to the clinical management of GBM by helping to classify tumours, predict prognosis and assess treatment response. In this article, we review the current understanding of GBM pathophysiology and recent advances in GBM biomarker research, and discuss the potential clinical implications of promising biomarkers. A better understanding of GBM pathophysiology will allow researchers and clinicians to identify optimal biomarkers and methods of interpretation, leading to advances in tumour classification, prognosis prediction and treatment assessment.

Phase- targeted stimulation modulates phase-amplitude coupling in the motor cortex of the human brain.

BACKGROUND: Phase-amplitude coupling (PAC) in which the amplitude of a faster field potential oscillation is coupled to the phase of a slower rhythm, is one of the most well-studied interactions between oscillations at different frequency bands. In a healthy brain, PAC accompanies cognitive functions such as learning and memory, and changes in PAC have been associated with neurological diseases including Parkinson's disease (PD), schizophrenia, obsessive-compulsive disorder, Alzheimer's disease, and epilepsy. OBJECTIVE: /Hypothesis: In PD, normalization of PAC in the motor cortex has been reported in the context of effective treatments such as dopamine replacement therapy and deep brain stimulation (DBS), but the possibility of normalizing PAC through intervention at the cortex has not been shown in humans. Phase-targeted stimulation (PDS) has a strong potential to modulate PAC levels and potentially normalize it. METHODS: We applied stimulation pulses triggered by specific phases of the beta oscillations, the low frequency oscillations that define phase of gamma amplitude in beta-gamma PAC, to the motor cortex of seven PD patients at rest during DBS lead placement surgery We measured the effect on PAC modulation in the motor cortex relative to stimulation-free periods. RESULTS: We describe a system for phase-targeted stimulation locked to specific phases of a continuously updated slow local field potential oscillation (in this case, beta band oscillations) prediction. Stimulation locked to the phase of the peak of beta oscillations increased beta-gamma coupling both during and after stimulation in the motor cortex, and the opposite phase (trough) stimulation reduced the magnitude of coupling after stimulation. CONCLUSION: These results demonstrate the capacity of cortical phase-targeted stimulation to modulate PAC without evoking motor activation, which could allow applications in the treatment of neurological disorders associated with abnormal PAC, such as PD.

Prehospital Traumatic Brain Injury Management Clinical Pearls and Pathophysiology.

Traumatic brain injury (TBI) management is complex. The brain is a sensitive, high-maintenance organ that loses its ability to take care of itself upon injury, and our primary mission is to achieve and maintain optimal levels of cerebral blood flow (CBF) from the moment of injury until recovery. The authors provide a case and discuss prehospital patient management, including adequate oxygen saturation and blood pressure, early recognition of TBI, frequent exams, detailed charting and hand-off, and fast transport to the next echelon of care.

Apparent diffusion coefficient of piriform cortex and seizure outcome in mesial temporal lobe epilepsy after MR-guided laser interstitial thermal therapy: a single-institution experience.

OBJECTIVE: Piriform cortex (PC) is one of the critical structures in the epileptogenesis of mesial temporal lobe epilepsy (mTLE), but its role is poorly understood. The authors examined the utility of apparent diffusion coefficient (ADC; an MR-based marker of tissue pathology) of the PC as a predictor of seizure outcome in patients with mTLE undergoing MR-guided laser interstitial thermal therapy (MRgLITT). METHODS: A total of 33 patients diagnosed with mTLE who underwent MRgLITT at the authors' institution were included in the study. The 6-month postoperative seizure outcomes were classified using the International League Against Epilepsy (ILAE) system as good (complete seizure freedom, ILAE class I) and poor (seizure present, ILAE classes II-VI). The PC and ablation volumes were manually segmented from both the preoperative and intraoperative MRI sequences, respectively. The mean ADC intensities of 1) preablation PC; 2) total ablation volume; 3) ablated portion of PC; and 4) postablation residual PC were calculated and compared between good and poor outcome groups. Additionally, the preoperative PC volumes and proportion of PC volume ablated were examined and compared between the subjects in the two outcome groups. RESULTS: The mean age at surgery was 36.5 ± 3.0 years, and the mean follow-up duration was 1.9 ± 0.2 years. Thirteen patients (39.4%) had a good outcome. The proportion of PC ablated was significantly associated with seizure outcome (10.16 vs 3.30, p < 0.05). After accounting for the variability in diffusion tensor imaging acquisition parameters, patients with good outcome had a significantly higher mean ADC of the preablation PC (0.3770 vs -0.0108, p < 0.05) and the postoperative residual PC (0.4197 vs 0.0309, p < 0.05) regions compared to those with poor outcomes. No significant differences in ADC of the ablated portion of PC were observed (0.2758 vs -0.4628, p = 0.12) after performing multivariate analysis. CONCLUSIONS: A higher proportion of PC ablated was associated with complete seizure freedom. Preoperative and postoperative residual ADC measures of PC were significantly higher in the good seizure outcome group in patients with mTLE who underwent MRgLITT, suggesting that ADC analysis can assist with postablation outcome prediction and patient stratification.

Piriform Cortex Ablation Volume Is Associated With Seizure Outcome in Mesial Temporal Lobe Epilepsy.

BACKGROUND: Growing evidence suggests that piriform cortex resection during anterior temporal lobectomy is important for achieving good seizure outcome in mesial temporal lobe epilepsy (mTLE). However, the relationship between seizure outcome and piriform cortex ablation during MR-guided laser interstitial thermal therapy (MRgLITT) remains unclear. OBJECTIVE: To determine whether ablation of piriform cortex was associated with seizure outcome in patients with mTLE undergoing MRgLITT. METHODS: We performed preablation and postablation volumetric analyses of hippocampus, amygdala, piriform cortex, and ablation volumes in patients with mTLE who underwent MRgLITT at our institution from 2014 to 2019. RESULTS: Thirty nine patients with mTLE were analyzed. In univariate logistic regression, percent piriform cortex ablation was associated with International League Against Epilepsy (ILAE) class 1 at 6 months (odds ratio [OR] 1.051, 95% CI [1.001-1.117], P = .045), whereas ablation volume, percent amygdala ablation, and percent hippocampus ablation were not ( P > .05). At 1 year, ablation volume was associated with ILAE class 1 (OR 1.608, 95% CI [1.071-2.571], P = .021) while percent piriform cortex ablation became a trend (OR 1.050, 95% CI [0.994-1.109], P = .054), and both percent hippocampus ablation and percent amygdala ablation were not significantly associated with ILAE class 1 ( P > .05). In multivariable logistic regression, only percent piriform cortex ablation was a significant predictor of seizure freedom at 6 months (OR 1.085, 95% CI [1.012-1.193], P = .019) and at 1 year (OR 1.074, 95% CI [1.003-1.178], P = .041). CONCLUSION: Piriform cortex ablation volume is associated with seizure outcome in patients with mTLE undergoing MRgLITT. The piriform cortex should be considered a high yield ablation target to achieve good seizure outcome.

Spinal cord untethering and midline myelotomy for delayed, symptomatic post-traumatic syringomyelia due to retained ballistic fragments: case report.

INTRODUCTION: Post-traumatic syringomyelia is an uncommon complication after traumatic spinal cord injury. This case study details our decision-making and surgical approach for a patient with symptomatic post-traumatic syringomyelia after sustaining a gunshot wound. CASE PRESENTATION: A 24-year-old man with past medical history of distant American Spinal Injury Association Impairment Grade B spinal cord injury due to ballistic injury developed delayed post-traumatic syringomyelia, resulting in unilateral sensory loss and left upper extremity weakness. CT and MR imaging revealed a syrinx spanning his cervical and thoracic spine causing significant spinal cord compression. To relieve achieve decompression and restore CSF flow dynamics, we performed a bony extradural decompression, bullet fragment extraction, spinal cord untethering, and midline myelotomy. Postoperatively, the patient demonstrated clinical and radiographical improvement. DISCUSSION: Post-traumatic syringomyelia is potentially morbid sequalae of spinal cord injuries. Suspicion for post-traumatic syringomyelia should be maintained in patients with delayed, progressive neurologic deficits. In this setting, surgical intervention may require extradural and intradural procedures to mitigate neural compression along the dilated central canal by the syrinx.

Severity of intraventricular extension correlates with level of admission glucose after intracerebral hemorrhage.

BACKGROUND AND PURPOSE: Hyperglycemia after spontaneous intracerebral hemorrhage (ICH) is associated with poor outcome, but the pathophysiology of ICH-induced glucose dysregulation remains unclear. We sought to identify clinical and radiographic parameters of ICH that are associated with admission hyperglycemia. METHODS: Patients admitted to the Columbia University Medical Center Neurological Intensive Care Unit with spontaneous ICH between January 2009 and September 2010 were prospectively enrolled in the ICH Outcomes Project. Clinical, radiographic, and laboratory data were collected prospectively. Receiver operating characteristic analysis was used to identify the glucose level with optimal sensitivity and specificity for in-hospital mortality. Logistic and linear regression analyses were used to identify independent predictors of outcome measures where appropriate. RESULTS: One hundred four patients admitted during the study period were included in the analysis. Mean admission glucose level was 8.23 ± 3.15 mmol/L (3.83 to 18.89 mmol/L) and 23.2% had a history of diabetes mellitus. Admission glucose was significantly associated with discharge (P=0.003) and 3-month mortality (P=0.002). Critical hyperglycemia defined at 10 mmol/L independently predicted discharge mortality (P=0.027; OR, 4.381; 95% CI, 1.186 to 16.174) and 3-month mortality (P=0.011; OR, 10.95; 95% CI, 1.886 to 62.41). Admission intraventricular extension score (P=0.038; OR, 1.117; 95% CI, 1.043 to 1.197) and diabetes mellitus (P=0.002; OR, 5.530; 95% CI, 1.833 to 16.689) were independent predictors of critical hyperglycemia. The intraventricular extension score (B=0.115, P=0.001) linearly correlated with admission glucose level (R=0.612, P=0.001) after adjusting for other clinical variables. CONCLUSIONS: Admission hyperglycemia after spontaneous ICH is associated with poor outcome and potentially related to the presence and severity of intraventricular extension.

Polymorphisms in complement component 3 (C3F) and complement factor H (Y402H) increase the risk of postoperative neurocognitive dysfunction following carotid endarterectomy.

BACKGROUND: Up to 28% of patients undergoing carotid endarterectomy (CEA) are estimated to experience neurocognitive dysfunction following surgery. The complement cascade plays a central role in ischaemia-reperfusion injury. The authors investigated the effect of common polymorphisms in the complement component 3 (C3F) and complement factor H (CFH Y402H) genes on incidence of neurocognitive dysfunction post-CEA. METHODS: This study examined a nested cohort of prospectively recruited patients receiving elective CEA, who were genotyped for the C3F or Y402H polymorphisms. Each patient underwent a standard battery of eight neuropsychometric tests before, and 1 day and 30 days after, surgery. RESULTS: 57 of 142 (40%) CEA patients had at least one copy of the C3F allele (C3F+), and 17 of 137 (12%) patients had two copies of the CFH Y402H allele (Y402H++). At postoperative day 1, patients were three times (OR 3.05, p=0.045) or six times (OR 6.41, p=0.006) more likely to experience moderate-to-severe neurocognitive dysfunction if they carried the C3F+ or Y402H++ genotype, respectively. Patients with both risk genotypes had an almost eightfold risk of dysfunction (OR 7.67, p=0.046). Right-hand-dominant C3F+ subjects undergoing right-side CEA performed significantly worse on tests of visuospatial function than C3F- subjects. At day 30, C3F+ and Y402H++ genotypes trended towards significance as predictors of dysfunction (p=0.07 and p=0.22, respectively). CONCLUSION: The C3F and Y402H polymorphisms are strong independent predictors of moderate-to-severe neurocognitive dysfunction at 1 day following CEA. Furthermore, patients undergoing right-sided CEA are predisposed to deficits associated with cortex ipsilateral to the operative carotid artery.

Advances in neuroprotective strategies: potential therapies for intracerebral hemorrhage.

Intracerebral hemorrhage (ICH) is associated with higher mortality and morbidity than any other form of stroke. However, there currently are no treatments proven to improve outcomes after ICH, and therefore, new effective therapies are urgently needed. Growing insight into ICH pathophysiology has led to the development of neuroprotective strategies that aim to improve the outcome through reduction of secondary pathologic processes. Many neuroprotectants target molecules or pathways involved in hematoma degradation, inflammation or apoptosis, and have demonstrated potential clinical benefits in experimental settings. We extensively reviewed the current understanding of ICH pathophysiology as well as promising experimental neuroprotective agents with particular focus on their mechanisms of action. Continued advances in ICH knowledge, increased understanding of neuroprotective mechanisms, and improvement in the ability to modulate molecular and pathologic events with multitargeting agents will lead to successful clinical trials and bench-to-bedside translation of neuroprotective strategies.

Isoflurane preconditioning affords functional neuroprotection in a murine model of intracerebral hemorrhage.

INTRODUCTION: Exposure to isoflurane gas prior to neurological injury, known as anesthetic preconditioning, has been shown to provide neuroprotective benefits in animal models of ischemic stroke. Given the common mediators of cellular injury in ischemic and hemorrhagic stroke, we hypothesize that isoflurane preconditioning will provide neurological protection in intracerebral hemorrhage (ICH). METHODS: 24 h prior to intracerebral hemorrhage, C57BL/6J mice were preconditioned with a 4-h exposure to 1% isoflurane gas or room air. Intracerebral hemorrhage was performed using a double infusion of 30-µL autologous whole blood. Neurological function was evaluated at 24, 48 and 72 h using the 28-point test. Mice were sacrificed at 72 h, and brain edema was measured. RESULTS: Mice preconditioned with isoflurane performed better than control mice on 28-point testing at 24 h, but not at 48 or 72 h. There was no significant difference in ipsilateral hemispheric edema between mice preconditioned with isoflurane and control mice. CONCLUSION: These results demonstrate the early functional neuroprotective effects of anesthetic preconditioning in ICH and suggest that methods of preconditioning that afford protection in ischemia may also provide protection in ICH.

Improving patient selection for endovascular treatment of acute cerebral ischemia: a review of the literature and an external validation of the Houston IAT and THRIVE predictive scoring systems.

Outcome after intraarterial therapy (IAT) for acute ischemic stroke remains variable, suggesting that improved patient selection is needed to better identify patients likely to benefit from treatment. The authors evaluate the predictive accuracies of the Houston IAT (HIAT) and the Totaled Health Risks in Vascular Events (THRIVE) scores in an independent cohort and review the existing literature detailing additional predictive factors to be used in patient selection for IAT. They reviewed their center's endovascular records from January 2004 to July 2010 and identified patients who had acute ischemic stroke and underwent IAT. They calculated individual HIAT and THRIVE scores using patient age, admission National Institutes of Health Stroke Scale (NIHSS) score, admission glucose level, and medical history. The scores' predictive accuracies for good outcome (discharge modified Rankin Scale score ≤ 3) were analyzed using receiver operating characteristics analysis. The THRIVE score predicts poor outcome after IAT with reasonable accuracy and may perform better than the HIAT score. Nevertheless, both measures may have significant clinical utility; further validation in larger cohorts that accounts for differences in patient demographic characteristics, variation in time-to-treatment, and center preferences with respect to IAT modalities is needed. Additional patient predictive factors have been reported but not yet incorporated into predictive scales; the authors suggest the need for additional data analysis to determine the independent predictive value of patient admission NIHSS score, age, admission hyperglycemia, patient comorbidities, thrombus burden, collateral flow, time to treatment, and baseline neuroimaging findings.

A comparative evaluation of existing grading scales in intracerebral hemorrhage.

BACKGROUND: In recent years, a multitude of clinical grading scales have been created to help identify patients at greater risk of poor outcome following ICH. We sought to validate and compare eight of the most frequently used ICH grading scales in a prospective cohort. METHODS: Eight grading scales were calculated for 67 patients with non-traumatic ICH enrolled in the prospective intracerebral hemorrhage outcomes project (ICHOP) database. Receiver operating characteristic (ROC) analysis, including area under the curve (AUC) and maximum Youden Index were used to assess the ability of each score to predict in-hospital mortality, long-term (3 months) mortality, and functional outcome at 3 months (mRS ≥ 3). RESULTS: All scales demonstrated excellent to outstanding discrimination for in-hospital and long-term mortality, with no significant differences between them after controlling for the false discovery rate. All scales demonstrated acceptable to outstanding discrimination for functional outcome at 3 months, with the new ICH score demonstrating significantly lower AUC than 6 of the 8 scores. Essen ICH score was the only score to demonstrate outstanding discrimination for each outcome measure. CONCLUSION: Though significant differences were minimal in our cohort, we showed the existing selection of ICH grading scales to be useful in stratifying patients according to risk of mortality and poor functional outcome. Continued validation and comparison in large prospective cohorts will bring the goal of a singular prognostic model for ICH closer to fruition.

Opioid use and spinal cord stimulation therapy: The long game.

Spinal cord stimulation (SCS) has been considered as an alternative therapy to reduce opioid requirements in certain chronic pain disorders. However, information on long-term opioid consumption patterns and their impact on SCS device explantation is lacking. We conducted a retrospective study of 45 patients to characterize long-term patterns of opioid usage after SCS implantation. Daily morphine equivalent dosage (MED) increased, decreased, and remained the same in 40%, 40%, and 20% of patients at 1-year follow-up, respectively. Twelve (27%) underwent explantation due to treatment failure at a median of 18 months after implantation. Pre-operative opioid status (naïve vs. active use) was not associated with explantation (18% vs. 29%, p = 0.699) and neither was the daily MED change status (i.e. increased, decreased, unchanged) at 1-year (p = 0.499, 1.000, 0.735, respectively). Following explantation, reduction in the daily MED was seen in 92% of patients with dosages falling below pre-operative baseline in nine. Among the opioid naïve patients, 55% were on opioids at last follow-up (average 32.4 ± 14.6 months). Our results indicate that daily opioid consumption does not decrease in most patients 1-year after SCS implantation. Furthermore, post-operative evaluation beyond 1-year is necessary to assess the efficacy and durability of SCS therapy as well as its impact on opioid requirement. Lastly, rigorous patient selection and pre-operative risk assessment for misuse and dependence are paramount to improving outcome after SCS implantation.

Total Fasting and Dehydration in the Operating Room: How Can Surgeons Survive and Thrive?

OBJECTIVES: Hydration and nutrition are critical to achieving optimal performance. This study aimed to assess the impact of limited oral intake in the operating room environment on surgical resident health, well-being, and performance. DESIGN: Electronic survey was sent to 94 surgical trainees at our institution in 2020. Chi-square analyses were performed to assess for differences in survey responses by sex. SETTING: A single tertiary-care institution. PARTICIPANTS: Surveys were sent to surgical residents and fellows in general surgery, neurosurgery, and orthopedic surgery. Seventy-nine (80%) of the 94 residents and fellows responded. RESULTS: Of the 79 responses, most trainees (79%) experienced dehydration within 6 hours of operating. Forty-four (56%) reported no fluid intake for greater than 6 hours on average, and 39 (49%) reported that they frequently had difficulty rehydrating in between cases. Most of the respondents (70%) frequently experienced symptoms of dehydration, including orthostasis, headache, and constipation. Fifty-six (71%) believed that dehydration frequently affected their performance. Compared to men, women were more likely to feel dehydrated within 4 hours of operating (58% vs. 25%, p = 0.005). Women were also more likely to have difficulty rehydrating in between cases (75% vs. 38%, p = 0.0026), experience symptoms of dehydration (92% vs. 60%, p = 0.0049), and report that dehydration affects surgical performance (88% vs. 64%, p = 0.0318). CONCLUSIONS: Prolonged fasting and dehydration are common issues that may negatively impact performance and wellbeing of surgical trainees. Also, dehydration may affect men and women differently.

Ultrasound in Traumatic Spinal Cord Injury: A Wide-Open Field.

Traumatic spinal cord injury (SCI) is a common and devastating condition. In the absence of effective validated therapies, there is an urgent need for novel methods to achieve injury stabilization, regeneration, and functional restoration in SCI patients. Ultrasound is a versatile platform technology that can provide a foundation for viable diagnostic and therapeutic interventions in SCI. In particular, real-time perfusion and inflammatory biomarker monitoring, focal pharmaceutical delivery, and neuromodulation are capabilities that can be harnessed to advance our knowledge of SCI pathophysiology and to develop novel management and treatment options. Our review suggests that studies that evaluate the benefits and risks of ultrasound in SCI are severely lacking and our understanding of the technology's potential impact remains poorly understood. Although the complex anatomy and physiology of the spine and the spinal cord remain significant challenges, continued technological advances will help the field overcome the current barriers and bring ultrasound to the forefront of SCI research and development.

Traumatic sacral dermoid cyst rupture with intracranial subarachnoid seeding of lipid particles: illustrative case.

BACKGROUND: Intracranial deposits of fat droplets are an unusual presentation of a spinal dermoid cyst after spontaneous rupture and are even more uncommon after trauma. Here, the authors present a case with this rare clinical presentation, along with a systematic review of the literature to guide decision making in these patients. OBSERVATIONS: A 54-year-old woman with Lynch syndrome presented with severe headache and sacrococcygeal pain after a traumatic fall. Computed tomography of the head revealed multifocal intraventricular and intracisternal fat deposits, which were confirmed by magnetic resonance imaging (MRI) of the neuroaxis; in addition, a ruptured multiloculated cyst was identified within the sacral canal with proteinaceous/hemorrhagic debris, most consistent with a sacral dermoid cyst with rupture into the cerebrospinal fluid (CSF) space. An unruptured sacral cyst was later noted on numerous previous MRI scans. In our systematic review, we identified 20 similar cases, most of which favored surgical treatment. LESSONS: Rupture of an intraspinal dermoid cyst must be considered when intracranial fat deposits are found in the context of cauda equina syndrome, meningism, or hydrocephalus. Complete tumor removal with close postoperative follow-up is recommended to decrease the risk of complications. CSF diversion must be prioritized if life-threatening hydrocephalus is present.