Faculty Bibliography

Laryngeal adductor reflex-continuous intraoperative neuromonitoring (LAR-CIONM) is a novel method of continuous intraoperative neuromonitoring. In contrast to other vagal nerve monitoring techniques, which elicit a laryngeal compound muscle action potential, LAR-CIONM elicits a laryngeal reflex response (LAR). In 300 nerves at risk monitored with LAR-CIONM, two patients have had postoperative permanent vocal fold immobility (VFI). Both patients exhibited a significant LAR amplitude increase prior to complete loss of signal. No other patients have exhibited LAR hyperexcitability. If confirmed in a larger sample, this represents the first time that a vagal intraoperative neuromonitoring technique can distinguish transient from permanent VFI, which could improve patient outcomes. Laryngoscope, 2019.

Internal and external segments of globus pallidus (GP) exert different functions in basal ganglia circuitry, despite their main connectional systems share the same topographical organization, delineating limbic, associative, and sensorimotor territories. The identification of internal GP sensorimotor territory has therapeutic implications in functional neurosurgery settings. This study is aimed at assessing the spatial coherence of striatopallidal, subthalamopallidal, and pallidothalamic pathways by using tractography-derived connectivity-based parcellation (CBP) on high quality diffusion MRI data of 100 unrelated healthy subjects from the Human Connectome Project. A two-stage hypothesis-driven CBP approach has been carried out on the internal and external GP. Dice coefficient between functionally homologous pairs of pallidal maps has been computed. In addition, reproducibility of parcellation according to different pathways of interest has been investigated, as well as spatial relations between connectivity maps and existing optimal stimulation points for dystonic patients. The spatial organization of connectivity clusters revealed anterior limbic, intermediate associative and posterior sensorimotor maps within both internal and external GP. Dice coefficients showed high degree of coherence between functionally similar maps derived from the different bundles of interest. Sensorimotor maps derived from the subthalamopallidal pathway resulted to be the nearest to known optimal pallidal stimulation sites for dystonic patients. Our findings suggest that functionally homologous afferent and efferent connections may share similar spatial territory within the GP and that subcortical pallidal connectional systems may have distinct implications in the treatment of movement disorders.

OBJECTIVES/OBJECTIVE:To analyze and compare differences between epidemiological and clinical aspects, as well as radiologic findings and treatment, in a series of adult patients with traumatic intracranial hypotension (TIH) and spontaneous intracranial hypotension (SIH) treated at our institution in order to identify predictors of recurrence. BACKGROUND:Cerebrospinal fluid hypotension headache (CSF-HH) is often caused by orthostasis and relieved by recumbency. Etiology can be either traumatic or spontaneous. Indirect signs of CSF hypotension are often observed on brain MRI. The most common therapeutic approach is conservative management and, when necessary, the use of an epidural blood patch. METHODS:Medical history and brain MRI of adult patients consulting our institution with a diagnosis of CSF-HH between January 2010 and March 2019, were retrospectively reviewed. Clinical criteria as per the International Classification of Headache Disorders, 3rd edition, were applied. Presence of typical MRI findings were assessed by two experienced neuroradiologists, previously informed of patients' clinical characteristics. Patients were divided into two different groups, namely: Group A: Spontaneous Intracranial Hypotension (SIH) and Group B: Traumatic Intracranial Hypotension (TIH). Recurrence was defined as return of symptoms after one month of remission. In order to find predictors of recurrent intracranial hypotension the patients were divided into three groups: Recurrent Orthostatic headache (ROH); (33 cases; 25%); Non-Recurrent Orthostatic headache (NROH) (84; 61%) and Patients missing follow-up (20; 15%). The latter were excluded from the regression analysis. RESULTS:137 patients with CSF-HH were identified: 80 traumatic (54 women, age 33.8 ± 10.4 years) and 57 spontaneous (31 women, age 43.9 ± 15.2 years). Median follow-up was 35 months (range: 8 months-9 years). Compared with TIH, patients with SIH showed lower frequency of orthostatic headache and higher frequency of aural fullness. Also, in patients with SIH, brain MRI showed a higher frequency of pachymeningeal enhancement, ventricular collapse, cisternal obliteration, posterior fossa crowding, brainstem distortion, and a more likely presence of subdural collections. Patients with SIH required an epidural blood patch treatment more often, showed higher recurrence rates, and were more prone to develop subdural hematomas. RECURRENCE/UNASSIGNED:As more days elapsed between headache onset and clinical consultation, the presence of spontaneous intracranial hypotension, tinnitus, and thoraco-lumbo-sacral pain were all more common in patients with recurrence. Findings on brain MRI suggesting higher recurrence rates in patients included: ventricular collapse, brainstem distortion, and posterior fossa crowding. Patients treated with invasive therapy (epidural blood patch) presented a higher recurrence rate. In the multivariate regression analysis, the only independent predictor of recurrence after adjusting for age, sex and traumatic vs spontaneous cause of IH, was brainstem distortion diagnosed on MRI (OR 5.13, 95% CI: 1.2-21.7; p = 0.026). CONCLUSIONS:SIH and TIH can no longer be likened, since there is considerable variability in clinical presentation, imaging findings, response to treatment and recurrence rates. Anatomical abnormalities underlying SIH leaks are often complex and not simply a disruption of normal structures as encountered in TIH, which could explain why treatment success is poor and recurrence rates remain high.

Severe acute respiratory syndrome coronavirus 2 is a novel cause of organ dysfunction in children, presenting as either coronavirus disease 2019 with sepsis and/or respiratory failure or a hyperinflammatory shock syndrome. Clinicians must now consider these diagnoses when evaluating children for septic shock and sepsis-associated organ dysfunction. The Surviving Sepsis Campaign International Guidelines for the Management of Septic Shock and Sepsis-associated Organ Dysfunction in Children provide an appropriate framework for the early recognition and initial resuscitation of children with sepsis or septic shock caused by all pathogens, including severe acute respiratory syndrome coronavirus 2. However, the potential benefits of select adjunctive therapies may differ from non-coronavirus disease 2019 sepsis.

This study examined the effect of increasing material-specific verbal and visual memory impairment severity on Rey 15-Item Test (RFIT) and RFIT/Recognition Trial performance. Data from 146 clinically referred patients (109 valid/37 invalid) who completed the RFIT, Brief Visuospatial Memory Test-Revised, and Rey Auditory Verbal Learning Test were analyzed. Rey Auditory Verbal Learning Test/BVMT memory impairment was operationalized as ≥40T (no memory impairment), 30T-39T (mild memory impairment), or ≤29T (severe memory impairment). Medium-to-large correlations emerged between the RFIT and memory measures. Significantly more patients with impaired visual memory, and to a lesser extent verbal memory, failed the RFIT and RFIT/Recognition. RFIT and RFIT/Recognition produced areas under the curve = .80-.90 for detecting invalidity and strong associated psychometric properties among patients without memory impairment, but both yielded low and largely unacceptable accuracy (areas under the curve = .57-.71) when verbal or visual memory impairment of any severity was present. In sum, RFIT performance was significantly affected by increasing material-specific memory deficits, such that it produced acceptable accuracy among unimpaired patients, but accuracy greatly diminished with memory impairment, which is antithetical to a sound performance validity test. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

BACKGROUND:Despite innovations in left ventricular assist devices (LVAD) technology, stroke remains a leading cause of morbidity and mortality in this population. Major clinical trials of LVAD have used various definitions and approaches to measuring stroke outcomes which may limit comparison of stroke risk between different devices. METHODS:Data from the five major LVAD randomized, controlled, trials was abstracted to compare definitions of stroke (composite, ischemic, hemorrhagic and disabling) and stroke event rates across trials. Methodological limitations and suggestions to improve research and clinical practices for stroke and LVAD were identified. RESULTS:Comparison of stroke events across LVAD clinical trials is confounded by methodological variability including heterogeneity in stroke definitions, non-standardized evaluation of stroke etiology, oversimplification of stroke severity classification, and inconsistent event rate reporting due to data censoring at the time of death or transplant. Variability in the study of stroke in LVAD patients limits the ability to compare devices and design prevention strategies to mitigate stroke risk. CONCLUSIONS:Based on this review, we propose that future clinical trials: 1) utilize standardized stroke definitions and define stroke subtypes, 2) ensure that neurologists are integrated in study design and event adjudication, 3) include more thorough evaluations of stroke etiology using multimodality techniques, and 4) adopt the National Institutes of Health Stroke Scale to define stroke severity.