Michael Lyerly

The pediatric Chiari I malformation: a review

BackgroundBoth the diagnosis and treatment regimens for the Chiari I malformation (CIM) are varied and controversial. The present paper analyzes the literature regarding this form of hindbrain herniation in regard to definition, anatomy, pathobiology, symptoms, findings, treatment, and outcomes.DiscussionsAppropriate literature germane to the CIM is reviewed and discussed. There is variation in the reported anatomy, outcome, and treatment for children with CIM. Based on the literature, most patients have preoperative symptoms or findings (e.g., syringomyelia) improve no matter what surgical technique is utilized. However, standardized treatment paradigms based on randomized controlled studies are still necessary to elucidate the optimal selection and treatment criteria.

Racial and Gender Differences in Stroke Severity, Outcomes and Treatment in Patients with Acute Ischemic Stroke

BACKGROUND Previous research has indicated that women and blacks have worse outcomes after acute ischemic stroke (AIS). Little research has been done to investigate the combined influence of race and gender in the presentation, treatment, and outcome of patients with AIS. We sought to determine the association of race and gender on initial stroke severity, thrombolysis, and functional outcome after AIS. METHODS AIS patients who presented to 2 academic medical centers in the United States (2004-2011) were identified through prospective registries. In-hospital strokes were excluded. Stroke severity, measured by admission National Institutes of Health Stroke Scale (NIHSS) scores, treatment with tissue plasminogen activator (tPA), neurologic deterioration (defined by a ≥2-point increase in NIHSS score), and functional outcome at discharge, measured by the modified Rankin Scale, were investigated. These outcomes were compared across race/gender groups. A subanalysis was conducted to assess race/gender differences in exclusion criteria for tPA. RESULTS Of the 4925 patients included in this study, 2346 (47.6%) were women and 2310 (46.9%) were black. White women had the highest median NIHSS score on admission (8), whereas white men had the lowest median NIHSS score on admission (6). There were no differences in outcomes between black men and white men. A smaller percentage of black women than white women were treated with tPA (27.6% versus 36.6%, P < .0001), partially because of a greater proportion of white women presenting within 3 hours (51% versus 45.5%, P = .0005). Black women had decreased odds of poor functional outcome relative to white women (odds ratio [OR] = .85, 95% confidence interval [CI] .72-1.00), but after adjustment for baseline differences in age, NIHSS, and tPA use, this association was no longer significant (OR = 1.2, 95% CI .92-1.46, P = .22). Black women with an NIHSS score less than 7 on admission were at lower odds of receiving tPA than the other race/gender groups, even after adjusting for arriving within 3 hours and admission glucose (OR = .66, 95% CI .44-.99, P = .0433). CONCLUSION Race and gender were not significantly associated with short-term outcome, although black women were significantly less likely to be treated with tPA. Black women had more tPA exclusions than any other group. The primary reason for tPA exclusion in this study was not arriving within 3 hours of stroke symptom onset. Given the growth in incident strokes projected in minority groups in the next 4 decades, identifying factors that contribute to black women not arriving to the emergency department in time are of great importance.

Weight changes associated with unilateral STN DBS and advanced PD

Weight gain following bilateral subthalamic nucleus deep brain stimulation (STN DBS) in Parkinson disease (PD) has been characterized previously, but little is known about changes in weight following unilateral STN DBS. Weight gain of approximately 10 kg at one year after bilateral STN DBS for PD has been noted in previous studies, and PD in the absence of DBS has been associated with weight loss. A case-control comparison evaluated the change in weight following unilateral STN DBS in PD. In 39 patients who underwent unilateral STN DBS for PD, we measured the weight change over 1 year versus both preoperative weight change and the weight change in 40 age- and disease severity-matched PD controls without DBS. Regression analyses incorporating age, gender, baseline weight in case or control were conducted to assess weight changes. At 12 months following surgery, the mean weight of unilateral STN DBS patients increased by 4.3+/-7.2 kg versus the preoperative baseline weight (p<0.001) and this increase was 4.8 kg compared with the controls (p=0.015). Over a 1 year time interval, weight gain occurred in 41% of the preoperative unilateral STN DBS patients and 45% of the PD controls, while 85% of the unilateral STN DBS patients had gained weight at 12 months after surgery (p<0.0001, respectively, chi square test). We conclude that unilateral STN DBS in PD is associated with weight gain, which offsets weight loss associated with advanced PD.

Infections Present on Admission Compared with Hospital-Acquired Infections in Acute Ischemic Stroke Patients

BACKGROUND To date, few studies have assessed the influence of infections present on admission (POA) compared with hospital-acquired infections (HAIs) on neurologic deterioration (ND) and other outcome measures in acute ischemic stroke (AIS). METHODS Patients admitted with AIS to our stroke center (July 2010 to December 2010) were retrospectively assessed. The following infections were assessed: urinary tract infection, pneumonia, and bacteremia. Additional chart review was performed to determine whether the infection was POA or HAI. We assessed the relationship between infections in ischemic stroke patients and several outcome measures including ND and poor functional outcome. A mediation analysis was performed to assess the indirect effects of HAI, ND, and poor functional outcome. RESULTS Of the 334 patients included in this study, 77 had any type of infection (23 POA). After adjusting for age, National Institutes of Health Stroke Scale at baseline, glucose on admission, and intravenous tissue plasminogen activator, HAI remained a significant predictor of ND (odds ratio [OR]=8.8, 95% confidence interval [CI]: 4.2-18.7, P<.0001) and poor functional outcome (OR=41.7, 95% CI: 5.2-337.9, P=.005), whereas infections POA were no longer associated with ND or poor functional outcome. In an adjusted analysis, we found that 57% of the effect from HAI infections on poor functional outcome is because of mediation through ND (P<.0001). CONCLUSIONS Our data suggests that HAI in AIS patients increases the odds of experiencing ND and subsequently increases the odds of being discharged with significant disability. This mediated effect suggests a preventable cause of ND that can thereby decrease the odds of poor functional outcomes after an AIS.

Systemic Inflammatory Response Syndrome in Tissue-Type Plasminogen Activator–Treated Patients is Associated With Worse Short-term Functional Outcome

Background and Purpose— Systemic inflammatory response syndrome (SIRS) is a generalized inflammatory state. The primary goal of the study was to determine whether differences exist in outcomes in SIRS and non-SIRS intravenous tissue-type plasminogen activator–treated patients. Methods— Consecutive patients were retrospectively reviewed for the evidence of SIRS during their admission. SIRS was defined as the presence of ≥2 of the following: body temperature <36°C or >38°C, heart rate >90, respiratory rate >20, and white blood cells <4000/mm or >12 000 mm, or >10% bands. Patients diagnosed with infection (via positive culture) were excluded. Results— Of the 241 patients, 44 had evidence of SIRS (18%). Adjusting for pre–tissue-type plasminogen activator National Institutes of Health Stroke Scale, age, and race, SIRS remained a predictor of poor functional outcome at discharge (odds ratio [OR], 2.58; 95% confidence interval [CI], 1.16–5.73; P=0.0197). Conclusions— In our sample of tissue-type plasminogen activator–treated (tPA) patients, ~1 in 5 patients developed SIRS. Furthermore, we found the presence of SIRS to be associated with poor short-term functional outcomes and prolonged length of stay.

The effects of telemedicine on racial and ethnic disparities in access to acute stroke care

Racial and ethnic disparities have been previously reported in acute stroke care. We sought to determine the effect of telemedicine (TM) on access to acute stroke care for racial and ethnic minorities in the state of Texas. Data were collected from the US Census Bureau, The Joint Commission and the American Hospital Association. Access for racial and ethnic minorities was determined by summing the population that could reach a primary stroke centre (PSC) or telemedicine spoke within specified time intervals using validated models. TM extended access to stroke expertise by 1.5 million residents. The odds of providing 60-minute access via TM were similar in Blacks and Whites (prevalence odds ratios (POR) 1.000, 95% CI 1.000–1.000), even after adjustment for urbanization (POR 1.000, 95% CI 1.000–1.001). The odds of providing access via TM were also similar for Hispanics and non-Hispanics (POR 1.000, 95% CI 1.000–1.000), even after adjustment for urbanization (POR 1.000, 95% CI 1.000–1.000). We found that telemedicine increased access to acute stroke care for 1.5 million Texans. While racial and ethnic disparities exist in other components of stroke care, we did not find evidence of disparities in access to the acute stroke expertise afforded by telemedicine.

Predictors of Systemic Inflammatory Response Syndrome in Ischemic Stroke Undergoing Systemic Thrombolysis with Intravenous Tissue Plasminogen Activator

BACKGROUND Systemic inflammatory response syndrome (SIRS) is an inflammatory process associated with poor outcomes in acute ischemic stroke (AIS) patients. However, no study to date has investigated predictors of SIRS in AIS patients treated with intravenous (IV) tissue plasminogen activator (tPA). METHODS Consecutive patients were retrospectively reviewed for evidence of SIRS during their acute hospitalization. SIRS was defined as the presence of 2 or more of the following: (1) body temperature less than 36°C or greater than 38°C, (2) heart rate greater than 90, (3) respiratory rate greater than 20, or (4) white blood cell count less than 4000/mm or greater than 12,000/mm or more than 10% bands for more than 24 hours. Those diagnosed with an infection were excluded. A scoring system was created to predict SIRS based on patient characteristics available at the time of admission. Logistic regression was used to evaluate potential predictors of SIRS using a sensitivity cutoff of ≥65% or area under the curve of .6 or more. RESULTS Of 212 patients, 44 had evidence of SIRS (21%). Patients with SIRS were more likely to be black (61% versus 54%; P = .011), have lower median total cholesterol at baseline (143 versus 167 mg/dL; P = .0207), and have history of previous stroke (51% versus 35%; P = .0810). Ranging from 0 to 6, the SIRS prediction score consists of African American (2 points), history of hypertension (1 point), history of previous stroke (1 point), and admission total cholesterol less than 200 (2 points). Patients with an SIRS score of 4 or more were 3 times as likely to develop SIRS when compared with patients with a score of ≤3 (odds ratio = 2.815, 95% confidence interval 1.43-5.56, P = .0029). CONCLUSIONS In our sample of IV tPA-treated AIS patients, clinical and laboratory characteristics available on presentation were able to identify patients likely to develop SIRS during their acute hospitalization. Validation is required in other populations. If validated, this score could assist providers in predicting who will develop SIRS after treatment with IV tPA.

Isolated CNS Whipple disease with normal brain MRI and false-positive CSF 14-3-3 protein: a case report and review of the literature

Whipple disease (WD) is usually a systemic infectious disease that can have central nervous system (CNS) involvement. WD confined to the CNS is extremely rare and difficult to diagnose, but can be fatal if not treated in a timely fashion. We present the case of a 42‐year‐old man with a subacute dementia accompanied by a movement disorder consisting of progressive supranuclear gaze palsy, myoclonus, and ataxia. Our patient lacked the typical magnetic resonance imaging (MRI) findings reported with isolated CNS WD and had a false‐positive cerebrospinal fluid (CSF) 14‐3‐3 protein. The patient expired, and definitive diagnosis of isolated CNS WD was made by autopsy with characteristic macrophage accumulations found in the brain but not in the gastrointestinal tract. We examine the literature on isolated CNS WD and discuss how these previously unreported findings make a rare diagnosis even more challenging. The reported patient is the first in the literature with tissue diagnosis of isolated CNS WD in the setting of normal brain MRI and positive CSF 14‐3‐3 protein. Isolated CNS WD should be added to the list of considerations for a false‐positive CSF 14‐3‐3 protein. Even in the absence of typical MRI lesions, a patient with subacute progressive dementia, supranuclear gaze palsy, and other various neurologic abnormalities should have the diagnosis of isolated CNS WD considered.

Impact of telemedicine on access to acute stroke care in the state of Texas

To examine the impact of telemedicine (TM) on access to acute stroke care and expertise in the state of Texas.

Hemorrhagic Transformation (HT) and Symptomatic Intracerebral Hemorrhage (sICH) Risk Prediction Models for Postthrombolytic Hemorrhage in the Stroke Belt

Background Symptomatic intracerebral hemorrhage (sICH) remains the most feared complication of intravenous tissue plasminogen activator (IV tPA) treatment. We aimed to investigate how previously validated scoring methodologies would perform in treated patients in two US Stroke Belt states. Methods and Results We retrospectively reviewed consecutive patients from two centers in two Stroke Belt states who received IV tPA (2008–2011). We assessed the ability of three models to predict sICH. sICH was defined as a type 2 parenchymal hemorrhage with deterioration in National Institutes of Health Stroke Scale (NIHSS) score of ≥4 points or death. Among 457 IV tPA-treated patients, 19 (4.2%) had sICH (mean age 68, 26.3% Black, 63.2% female). The Cucchiara model was most predictive of sICH in the entire cohort (AUC: 0.6528) and most predictive of sICH among Blacks (OR = 6.03, 95% CI 1.07–34.1, P = 0.0422) when patients were dichotomized by score. Conclusions In our small sample from the racially heterogeneous US Stroke Belt, the Cucchiara model outperformed the other models at predicting sICH. While predictive models should not be used to justify nontreatment with thrombolytics, those interested in understanding contributors to sICH may choose to use the Cucchiara model until a Stroke Belt model is developed for this region.