Clinical Reasoning: A 24-Year-Old Woman With Penetrating Neck Injury From a Needlefish.

Evaluating patients with a traumatic spinal cord injury can be complicated by other injuries. In this case, a 24-year-old woman injured by a needlefish presented with combined motor and sensory defects, cranial nerve deficits, and a blunt vascular injury. This case highlights the importance of neurologic and vascular localizations and an understanding of spinal cord injuries involving various ascending and descending tracts. Appreciation of these anatomical considerations through this case illustrates the diagnostic approach to neurologic evaluation. While we present a traumatic etiology for multiple neurologic syndromes, this case gives readers an opportunity to develop a comprehensive differential diagnosis and tailor investigations for other relevant etiologies. Readers walking through this stepwise process will ultimately arrive at several distinct but related diagnoses.

Factors influencing withdrawal of life-supporting treatment in cervical spinal cord injury: a large multicenter observational cohort study.

BACKGROUND: Traumatic spinal cord injury (SCI) leads to profound neurologic sequelae, and the provision of life-supporting treatment serves great importance among this patient population. The decision for withdrawal of life-supporting treatment (WLST) in complete traumatic SCI is complex with the lack of guidelines and limited understanding of practice patterns. We aimed to evaluate the individual and contextual factors associated with the decision for WLST and assess between-center differences in practice patterns across North American trauma centers for patients with complete cervical SCI. METHODS: This retrospective multicenter observational cohort study utilized data derived from the American College of Surgeons Trauma Quality Improvement Program database between 2017 and 2020. The study included adult patients (> 16 years) with complete cervical SCI. We constructed a multilevel mixed effect logistic regression model to adjust for patient, injury and hospital factors influencing WLST. Factors associated with WLST were estimated through odds ratios with 95% confidence intervals. Hospital variability was characterized using the median odds ratio. Unexplained residual variability was assessed through the proportional change in variation between models. RESULTS: We identified 5070 patients with complete cervical SCI treated across 477 hospitals, of which 960 (18.9%) had WLST. Patient-level factors associated with significantly increased likelihood of WLST were advanced age, male sex, white race, prior dementia, low presenting Glasgow Coma Scale score, having a pre-hospital cardiac arrest, SCI level of C3 or above, and concurrent severe injury to the head or thorax. Patient-level factors associated with significantly decreased likelihood of WLST included being racially Black or Asian. There was significant variability across hospitals in the likelihood for WLST while accounting for case-mix, hospital size, and teaching status (MOR 1.51 95% CI 1.22-1.75). CONCLUSIONS: A notable proportion of patients with complete cervical SCI undergo WLST during their in-hospital admission. We have highlighted several factors associated with this decision and identified considerable variability between hospitals. Further work to standardize WLST guidelines may improve equity of care provided to this patient population.

"Instant 3D" Angiography: Novel Technique for Rapid Conversion of 2D Angiograms into 3D Stereoscopic Videos.

BACKGROUND: Rotational angiography, often referred to as a "spin", is typically presented in 2D. Since rotational angiograms are composed of images acquired from multiple angles, we took advantage of this property to develop a method for converting any rotational angiogram into a 3 dimensional (3D) video. METHODS: Our aim was to develop a low cost and easily distributable solution without requiring additional hardware or altering acquisition techniques. Six previously acquired rotational angiograms from our institution were imported using custom-written code and exported as anaglyph (red-cyan) videos. RESULTS: The resulting 3D videos convey anatomical depth that is not apparent from viewing the 2D images alone. Processing time was 1.3 ± 0.6 s (mean ± SD) per angiogram. The only associated cost was $10 for red-cyan 3D glasses. Using our software, any rotational angiogram with at least 0.3 frames per degree of rotation can be converted into 3D. CONCLUSIONS: Our solution is an inexpensive and rapid method for generating stereoscopic videos from existing angiograms. It does not require any additional hardware and is readily deployable in low-resource settings. Because the videos are in anaglyph format, they are viewable on any 2 dimensional (2D) display in the interventional suite or operating room, on a mobile device, or at home.

A cellular taxonomy of the adult human spinal cord.

The mammalian spinal cord functions as a community of cell types for sensory processing, autonomic control, and movement. While animal models have advanced our understanding of spinal cellular diversity, characterizing human biology directly is important to uncover specialized features of basic function and human pathology. Here, we present a cellular taxonomy of the adult human spinal cord using single-nucleus RNA sequencing with spatial transcriptomics and antibody validation. We identified 29 glial clusters and 35 neuronal clusters, organized principally by anatomical location. To demonstrate the relevance of this resource to human disease, we analyzed spinal motoneurons, which degenerate in amyotrophic lateral sclerosis (ALS) and other diseases. We found that compared with other spinal neurons, human motoneurons are defined by genes related to cell size, cytoskeletal structure, and ALS, suggesting a specialized molecular repertoire underlying their selective vulnerability. We include a web resource to facilitate further investigations into human spinal cord biology.

Direct Puncture of the Superficial Temporal Artery in Embolization of a Scalp Arteriovenous Fistula: A Case Report.

We describe a minimally invasive endovascular approach to treat an arteriovenous fistula of the scalp. We performed a direct puncture of the lesion through the patient's scalp for liquid embolic agent injection along with external compression of the superficial temporal artery to perform a "manual pressure-cooker technique." The combination of these minimally invasive techniques resulted in an excellent clinical and radiographic outcome.

A Canadian National Survey of the Neurosurgical Management of Intracranial Abscesses.

OBJECTIVE: Intracerebral abscess is a life-threatening condition for which there are no current, widely accepted neurosurgical management guidelines. The purpose of this study was to investigate Canadian practice patterns for the medical and surgical management of primary, recurrent, and multiple intracerebral abscesses. METHODS: A self-administered, cross-sectional, electronic survey was distributed to active staff and resident members of the Canadian Neurosurgical Society and Canadian Neurosurgery Research Collaborative. Responses between subgroups were analyzed using the Chi-square test. RESULTS: In total, 101 respondents (57.7%) completed the survey. The majority (60.0%) were staff neurosurgeons working in an academic, adult care setting (80%). We identified a consensus that abscesses >2.5 cm in diameter should be considered for surgical intervention. The majority of respondents were in favor of excising an intracerebral abscess over performing aspiration if located superficially in non-eloquent cortex (60.4%), located in the posterior fossa (65.4%), or causing mass effect leading to herniation (75.3%). The majority of respondents were in favor of reoperation for recurrent abscesses if measuring greater than 2.5 cm, associated with progressive neurological deterioration, the index operation was an aspiration and did not include resection of the abscess capsule, and if the recurrence occurred despite prior surgery combined with maximal antibiotic therapy. There was no consensus on the use of topical intraoperative antibiotics. CONCLUSION: This survey demonstrated heterogeneity in the medical and surgical management of primary, recurrent, and multiple brain abscesses among Canadian neurosurgery attending staff and residents.

The Scanning Fiber Endoscope: A Novel Surgical and High-Resolution Imaging Device for Intracranial Neurosurgery.

BACKGROUND: The scanning fiber endoscope (SFE) is a novel medical imaging device that has been used in various vascular beds as a form of angioscopy, as well as in tracts and duct systems for endoluminal imaging. Owing to its miniaturized form, high resolution, and flexibility, it has demonstrated success in imaging across a wide range of diagnostic applications. OBJECTIVE: To demonstrate, by performing a third ventriculostomy and visualizing the cranial nerves and brainstem anatomy, that, without modification, the SFE can be used through a transcranial approach in a therapeutic intraventricular neurosurgical application. METHODS: A 3.7 French SFE system was used without modification on a live porcine model to perform a third ventriculostomy and acquire high-resolution images of the animal's ventricular system, cranial nerves, and brainstem. A side-by-side comparison was made with one of the current standard-of-care rigid endoscopes as a context for size and image quality. RESULTS: High-resolution video-rate imaging was used to assist the successful, uncomplicated performance of a third ventriculostomy. High-resolution endoscopic images of the brainstem and cranial nerves were acquired. CONCLUSION: Although the SFE has been shown to be a superior device for imaging, here we demonstrate its first use as a potential therapeutic device in intracranial neurosurgery.

Distracted Driving on YouTube: Categorical and Quantitative Analyses of Messages Portrayed.

BACKGROUND: Distracted driving is a global epidemic, injuring and killing thousands of people every year. To better understand why people still engage in this dangerous behavior, we need to assess how the public gets informed about this issue. Knowing that many people use the internet as their primary source of initial research on topics of interest, we conducted an assessment of popular distracted driving videos found on YouTube. OBJECTIVE: This study aimed to gauge the popularity of distracted driving videos and to assess the messages portrayed by classifying the content, context, and quality of the information available on YouTube. METHODS: We conducted a search on YouTube using 5 different phrases related to distracted driving. Videos with more than 3000 views that mentioned or portrayed any aspect of distracted driving were identified, collected, and analyzed. We measured popularity by the number of videos uploaded annually and the number of views and reactions. Two independent researchers reviewed all the videos for categorical variables. Content variables included distractions; consequences; orthopedic injuries; and whether the videos were real accounts, reenactments, fictitious, funny, serious, and graphic. Context variables assessed the setting of the events in the video, and quality of information was measured by the presence of peer-reviewed studies and inclusion and referencing of statistics. Discrepancies in data collection were resolved by consensus via the coding authors. A comparative subanalysis of the 10 most viewed videos and the overall results was also done. RESULTS: The study included a total of 788 videos for review, uploaded to YouTube from 2006 to 2018. An average of 61 videos with greater than 3000 views were uploaded each year (SD 34.6, range 3-113). All videos accumulated 223 million views, 104 million (46.50%) of them being among the 10 most viewed videos. The top 3 distractions depicted included texting, talking on the phone, and eating and/or drinking. Motor vehicle crashes (MVCs) and death were depicted in 742 (94.2%) videos, whereas 166 (21.1%) of the videos depicted injuries. Orthopedic injuries were described in 90 (11.4%) videos. Furthermore, 220 (27.9%) of the videos contained statistics, but only 27 (3.7%) videos referenced a peer-reviewed study. CONCLUSIONS: This study demonstrates that there is a high interest in viewing distracted driving videos, and the popularity of these videos appears to be relatively stable over time on a forum that fluxes based on the current opinions of its users. The videos mostly focused on phone-related distractions, overlooking many other equally or more common forms of distracted driving. Death, which in reality is a far less common distracted driving consequence than injuries, was portrayed 1.7 times as much. Surprisingly, orthopedic injuries, which lead to a massive source of long-term disability and often result from MVCs, are vastly underrepresented.

Hypertrophic Interstitial Neuropathy of the Trigeminal Nerve: Case Report and Literature Review.

BACKGROUND AND IMPORTANCE: Hypertrophic interstitial neuropathy (HIN) is an uncommon, non-neoplastic lesion typically affecting peripheral nerves. Cranial nerve (CN) involvement is exceedingly rare. We present a case of isolated trigeminal nerve HIN manifesting with V3 distribution neuralgia. CLINICAL PRESENTATION: A 50-yr-old male presented with left sided trigeminal neuralgia refractory to medical management. The patient underwent retromastoid craniectomy for possible microvascular decompression. Intra-operatively, the trigeminal nerve appeared to be focally enlarged with a sausage-like configuration. We selectively resected 1 fascicle which was predominantly involved. Histopathological examination revealed onion bulb formations composed of Schwann cells around centrally placed axons. A diagnosis of HIN was made. Postoperatively, the patient experienced complete resolution of symptoms. CONCLUSION: This is the third case of isolated trigeminal nerve HIN in the literature. We performed a selective resection in a patient presenting with trigeminal neuralgia, resulting in complete resolution of symptoms. It is reported here with intraoperative microscope images, along with a review and analysis of this topic as it related to CN.

Salvage Therapy for Childhood Medulloblastoma: A Single Center Experience.

INTRODUCTION: Children diagnosed with medulloblastoma (MB) who are refractory to upfront therapy or experience recurrence have very poor prognoses. Although phase I and phase II trials exist, these treatments bear significant treatment-related morbidity and mortality. METHODS: A retrospective review of children diagnosed with a recurrence of MB from 2002 to 2015 at McMaster University was undertaken. RESULTS: Recurrent disease in 10 patients involved leptomeningeal dissemination, with 3 experiencing local recurrence. In three recurrent patients the disease significantly progressed, and the children were palliated. The remaining 10 children underwent some form of salvage therapy, including surgical re-resection, radiation, and chemotherapy, either in isolation or in varying combinations. Of the 13 children experiencing treatment-refractory or recurrent disease, 4 are currently alive with a median follow-up of 38.5 months (75.5 months). Of the eight patients with molecular subgrouping data, none of the Wnt MB experienced recurrence. CONCLUSION: Recurrent MB carried a poor prognosis with a 5-year overall survival (OS) of 18.2% despite the administration of salvage therapy. The upfront therapy received, available treatment, and tolerability of the proposed salvage therapy resulted in significant heterogeneity in the treatment of our recurrent cohort.

Traitement de sauvetage dans le cas du médulloblastome chez l'enfant : une expérience menée au sein d'un établissement hospitalier. Introduction: Les enfants chez qui l'on a diagnostiqué un médulloblastome réfractaire à un traitement initial ou qui sont victimes d'une récidive présentent d'habitude des pronostics de guérison vraiment défavorables. Bien qu'il existe des traitements basés sur des essais cliniques de phases I et II, ces traitements ont tendance à produire des taux notables de morbidité et de mortalité. Méthodes: Nous avons ainsi mené à l'Université McMaster une analyse rétrospective des dossiers d'enfants chez qui l'on avait diagnostiqué entre 2002 et 2015 une récidive de médulloblastome. Résultats: La réapparition de cette maladie chez 10 patients a provoqué un phénomène de diffusion leptoméningée, trois d'entre eux étant victimes d'une récidive locale. Sur ces 10 jeunes patients, la maladie a progressé de façon importante : ces enfants ont alors été transférés aux soins palliatifs. Quant aux autres 10 enfants, ils ont subi un certain type de traitement de sauvetage (des résections chirurgicales, de la radiothérapie, de la chimiothérapie), que ce soit de façon exclusive ou en variant les combinaisons possibles. Sur les 13 enfants réfractaires à un traitement initial ou victimes d'une récidive, 4 sont toujours en vie, leur suivi médian ayant été de 38,5 mois (75,5 mois). Sur les 8 patients pour qui on a pu obtenir des données moléculaires, aucun de ceux qui étaient atteints d'un médulloblastome du sous-type Wnt n'a connu de récidive. Conclusion: Les médulloblastomes qui réapparaissent après une période de guérison complète présentent un pronostic de guérison défavorable. Leur taux de survie globale est en effet de 18,2 % au cours d'une période de 5 ans, et ce, même après avoir bénéficié d'un traitement de sauvetage. Ajoutons aussi que le type de traitement initial reçu, la disponibilité des traitements ainsi que la tolérance à l'égard des traitements de sauvetage proposés a entraîné une grande hétérogénéité dans le traitement de ces jeunes patients victimes d'une récidive.

Trigeminocardiac Reflex: Case Report and Literature Review of Intraoperative Asystole in Response to Manipulation of the Temporalis Muscle.

BACKGROUND: The trigeminocardiac reflex is a sudden onset of bradycardia, hypotension, apnea, or gastric hypermotility in response to stimulation of the trigeminal nerve. CASE DESCRIPTION: A 60-year-old female underwent a left orbitozygomatic craniotomy to debulk a large skull base epidermoid cyst compressing the brainstem and cranial nerves. Intraoperatively, retraction of the temporalis muscle consistently produced asystole. Cessation of retraction resulted in prompt return of sinus rhythm. CONCLUSIONS: Our report describes an unusual and extreme example of the trigeminocardiac reflex and explores possible etiologies. This is the third reported surgical case in which manipulation of the temporalis muscle alone was sufficient to elicit bradycardia and asystole, and the first such case within the context of neurosurgery. We emphasize the importance of surgical teams to be cognizant of such extreme examples of this reflex.

Cdk1 phosphorylation of Esp1/Separase functions with PP2A and Slk19 to regulate pericentric Cohesin and anaphase onset.

Anaphase onset is an irreversible cell cycle transition that is triggered by the activation of the protease Separase. Separase cleaves the Mcd1 (also known as Scc1) subunit of Cohesin, a complex of proteins that physically links sister chromatids, triggering sister chromatid separation. Separase is regulated by the degradation of the anaphase inhibitor Securin which liberates Separase from inhibitory Securin/Separase complexes. In many organisms, Securin is not essential suggesting that Separase is regulated by additional mechanisms. In this work, we show that in budding yeast Cdk1 activates Separase (Esp1 in yeast) through phosphorylation to trigger anaphase onset. Esp1 activation is opposed by protein phosphatase 2A associated with its regulatory subunit Cdc55 (PP2ACdc55) and the spindle protein Slk19. Premature anaphase spindle elongation occurs when Securin (Pds1 in yeast) is inducibly degraded in cells that also contain phospho-mimetic mutations in ESP1, or deletion of CDC55 or SLK19. This striking phenotype is accompanied by advanced degradation of Mcd1, disruption of pericentric Cohesin organization and chromosome mis-segregation. Our findings suggest that PP2ACdc55 and Slk19 function redundantly with Pds1 to inhibit Esp1 within pericentric chromatin, and both Pds1 degradation and Cdk1-dependent phosphorylation of Esp1 act together to trigger anaphase onset.