Preserved Cochlear CISS Signal is a Predictor for Hearing Preservation in Patients Treated for Vestibular Schwannoma With Stereotactic Radiosurgery.

BACKGROUND: Hearing preservation is a goal for many patients with vestibular schwannoma. We examined pretreatment magnetic resonance imaging (MRI) and posttreatment hearing outcome after stereotactic radiosurgery. METHODS: From 2004 to 2014, a cohort of 125 consecutive patients with vestibular schwannoma (VS) treated via stereotactic radiosurgery (SRS) were retrospectively reviewed. MRIs containing three-dimensional constructive interference in steady state or equivalent within 1 year before treatment were classified by two radiologists for pretreatment characteristics. "Good" hearing was defined as American Academy of Otolaryngology-Head and Neck Surgery class A. Poor hearing outcome was defined as loss of good pretreatment hearing after stereotactic radiosurgery. RESULTS: Sixty-one patients met criteria for inclusion. Most had tumors in the distal internal auditory canal (55%), separated from the brainstem (63%), oval shape (64%) without cysts (86%), and median volume of 0.85 ±â€Š0.55 cm. Pretreatment audiograms were performed a median of 108 ±â€Š173 days before stereotactic radiosurgery; 38% had good pretreatment hearing. Smaller tumor volume (p < 0.005) was the only variable associated with good pretreatment hearing. 49 (80%) patients had posttreatment audiometry, with median follow-up of 197 ±â€Š247 days. Asymmetrically decreased pretreatment cochlear CISS signal on the side of the VS was the only variable associated with poor hearing outcome (p = 0.001). Inter-rater agreement on cochlear three-dimensional constructive interference in steady state preservation was 91%. CONCLUSIONS: Decreased cochlear CISS signal may indicate a tumor's association with the cochlear neurovascular bundle, influencing endolymph protein concentration and creating an inability to preserve hearing. This important MRI characteristic can influence planning, counseling, and patient selection for vestibular schwannoma treatment.

Early Venous Thromboembolism Chemoprophylaxis After Traumatic Intracranial Hemorrhage.

BACKGROUND: Venous thromboembolism is a common complication of traumatic brain injury with an estimated incidence of 25% when chemoprophylaxis is delayed. The timing of initiating prophylaxis is controversial given the concern for hemorrhage expansion. OBJECTIVE: To determine the safety of initiating venous thromboembolic event (VTE) chemoprophylaxis within 24 h of presentation. METHODS: We performed a retrospective analysis of patients with traumatic intracranial hemorrhage presenting to a level I trauma center. Patients receiving early chemoprophylaxis (<24 h) were compared to the matched cohort of patients who received heparin in a delayed fashion (>48 h). The primary outcome of the study was radiographic expansion of the intracranial hemorrhage. Secondary outcomes included VTE, use of intracranial pressure (ICP) monitoring, delayed decompressive surgery, and all-cause mortality. RESULTS: Of 282 patients, 94 (33%) received chemoprophylaxis within 24 h of admission. The cohorts were evenly matched across all variables. The primary outcome occurred in 18% of patients in the early cohort compared to 17% in the delayed cohort (P = .83). Fifteen patients (16%) in the early cohort underwent an invasive procedure in a delayed fashion; this compares to 35 patients (19%) in the delayed cohort (P = .38). Five patients (1.7%) in our study had a VTE during their hospitalization; 2 of these patients received early chemoprophylaxis (P = .75). The rate of mortality from all causes was similar in both groups. CONCLUSION: Early (<24 h) initiation of VTE chemoprophylaxis in patients with traumatic intracranial hemorrhage appears to be safe. Further prospective studies are needed to validate this finding.

The magnitude of angular and translational displacement of dens fractures is dependent on the sagittal alignment of the cervical spine rather than the force of injury.

BACKGROUND CONTEXT: Although it is generally believed that the magnitude of dens fracture displacement is proportional to the amount of force applied to the cervical spine during injury, the factors responsible for displacement have not been studied. PURPOSE: Our aim was to determine factors that contribute to horizontal and angular displacement of dens fractures. STUDY DESIGN/SETTING: We conducted a retrospective review of adult patients who were admitted to our level 1 trauma center between January 1, 2008 and December 31, 2013. PATIENT SAMPLE: Angular and horizontal displacements of the fractured dens in 57 patients were measured. Subjects were grouped based on mechanism of fracture: motor vehicle accident, ground level fall, and higher falls. OUTCOME MEASURES: Cervical lordosis was measured between C2 and T1. C3-C4, C4-C5, C5-C6, and C6-C7 disc inclination angles were measured. Anteroposterior sagittal balance was assessed by comparing the sagittal position of the C2 body with the C7 body. METHODS: Data were analyzed using Pearson correlations, independent t tests, and support vector regression to construct predictive models that determine factors contributing to the angular and horizontal displacements. RESULTS: The mean horizontal displacement of the fractured dens was not significantly different among groups. However, the dens in those with ground level falls had a significantly greater mean fracture angle compared with the higher energy trauma groups (p=.01). There were positive correlations between angular displacement and C5-C6 disc space inclination angle (r=0.67, p<.01) and C6-C7 disc space inclination angle (r=0.61, p<.01). There were positive correlations between horizontal displacement and C6-C7 inclination angle (r=0.40, p<.01) and sagittal alignment (r=0.32, p<.01). The predictive model using all variables demonstrated that angular fracture displacement was only dependent on C5-C6 disc space inclination angle. Horizontal displacement was only dependent on C6-C7 inclination angle and anteroposterior sagittal balance. CONCLUSIONS: Disc space inclination angles of the lower cervical spine and the cervical sagittal balance most contribute to the magnitude of angular and horizontal displacement of the dens after fracture.

Alcohol use by urban bicyclists is associated with more severe injury, greater hospital resource use, and higher mortality.

Alcohol use is a risk factor for severe injury in pedestrians struck by motor vehicles. Our objective was to investigate alcohol use by bicyclists and its effects on riding behaviors, medical management, injury severity, and mortality within a congested urban setting. A hospital-based, observational study of injured bicyclists presenting to a Level I regional trauma center in New York City was conducted. Data were collected prospectively from 2012 to 2014 by interviewing all bicyclists presenting within 24 h of injury and supplemented with medical record review. Variables included demographic characteristics, scene-related data, Glasgow Coma Scale (GCS), computed tomography (CT) scans, and clinical outcomes. Alcohol use at the time of injury was determined by history or blood alcohol level (BAL) >0.01 g/dL. Of 689 bicyclists, 585 (84.9%) were male with a mean age of 35.2. One hundred four (15.1%) bicyclists had consumed alcohol prior to injury. Alcohol use was inversely associated with helmet use (16.5% [9.9-25.1] vs. 43.2% [39.1-47.3]). Alcohol-consuming bicyclists were more likely to fall from their bicycles (42.0% [32.2-52.3] vs. 24.2% [20.8-27.9]) and less likely to be injured by collision with a motor vehicle (52.0% [41.7-62.1] vs. 67.5% [63.5-71.3]). 80% of alcohol-consuming bicyclists underwent CT imaging at presentation compared with 51.5% of non-users. Mortality was higher among injured bicyclists who had used alcohol (2.9% [0.6-8.2] vs. 0.0% [0.0-0.6]). Adjusted multivariable analysis revealed that alcohol use was independently associated with more severe injury (Adjusted Odds Ratio 2.27, p = 0.001, 95% Confidence Interval 1.40-3.68). Within a dense urban environment, alcohol use by bicyclists was associated with more severe injury, greater hospital resource use, and higher mortality. As bicycling continues to increase in popularity internationally, it is important to heighten awareness about the risks and consequences of bicycling while under the influence of alcohol.

Traumatic injury in the United States: In-patient epidemiology 2000-2011.

BACKGROUND: Trauma is a leading cause of death and disability in the United States (US). This analysis describes trends and annual changes in in-hospital trauma morbidity and mortality; evaluates changes in age and gender specific outcomes, diagnoses, causes of injury, injury severity and surgical procedures performed; and examines the role of teaching hospitals and Level 1 trauma centres in the care of severely injured patients. METHODS: We conducted a retrospective descriptive and analytic epidemiologic study of an inpatient database representing 20,659,684 traumatic injury discharges from US hospitals between 2000 and 2011. The main outcomes and measures were survey-adjusted counts, proportions, means, standard errors, and 95% confidence intervals. We plotted time series of yearly data with overlying loess smoothing, created tables of proportions of common injuries and surgical procedures, and conducted survey-adjusted logistic regression analysis for the effect of year on the odds of in-hospital death with control variables for age, gender, weekday vs. weekend admission, trauma-centre status, teaching-hospital status, injury severity and Charlson index score. RESULTS: The mean age of a person discharged from a US hospital with a trauma diagnosis increased from 54.08 (s.e.=0.71) in 2000 to 59.58 (s.e.=0.79) in 2011. Persons age 45-64 were the only age group to experience increasing rates of hospital discharges for trauma. The proportion of trauma discharges with a Charlson Comorbidity Index score greater than or equal to 3 nearly tripled from 0.048 (s.e.=0.0015) of all traumatic injury discharges in 2000 to 0.139 (s.e.=0.005) in 2011. The proportion of patients with traumatic injury classified as severe increased from 22% of all trauma discharges in 2000 (95% CI 21, 24) to 28% in 2011 (95% CI 26, 30). Level 1 trauma centres accounted for approximately 3.3% of hospitals. The proportion of severely injured trauma discharges from Level 1 trauma centres was 39.4% (95% CI 36.8, 42.1). Falls, followed by motor-vehicle crashes, were the most common causes of all injuries. The total cost of trauma-related inpatient care between 2001 and 2011 in the US was $240.7 billion (95% CI 231.0, 250.5). Annual total US inpatient trauma-related hospital costs increased each year between 2001 and 2011, more than doubling from $12.0 billion (95% CI 10.5, 13.4) in 2001 to 29.1 billion (95% CI 25.2, 32.9) in 2011. CONCLUSIONS: Trauma, which has traditionally been viewed as a predicament of the young, is increasingly a disease of the old. The strain of managing the progressively complex and costly care associated with this shift rests with a small number of trauma centres. Optimal care of injured patients requires a reappraisal of the resources required to effectively provide it given a mounting burden.

A matched cohort comparison of clinical outcomes following microsurgical resection or stereotactic radiosurgery for patients with small- and medium-sized vestibular schwannomas.

OBJECTIVE A randomized trial that compares clinical outcomes following microsurgery (MS) or stereotactic radiosurgery (SRS) for patients with small- and medium-sized vestibular schwannomas (VSs) is impractical, but would have important implications for clinical decision making. A matched cohort analysis was conducted to evaluate clinical outcomes in patients treated with MS or SRS. METHODS The records of 399 VS patients who were cared for by 2 neurosurgeons and 1 neurotologist between 2001 and 2014 were evaluated. From this data set, 3 retrospective matched cohorts were created to compare hearing preservation (21 matched pairs), facial nerve preservation (83 matched pairs), intervention-free survival, and complication rates (85 matched pairs) between cases managed with SRS and patients managed with MS. Cases were matched for age at surgery (± 10 years) and lesion size (± 0.1 cm). To compare hearing outcomes, cases were additionally matched for preoperative Class A hearing according to the American Academy of Otolaryngology-Head and Neck Surgery guidelines. To compare facial nerve (i.e., cranial nerve [CN] VII) outcomes, cases were additionally matched for preoperative House-Brackmann (HB) score. Investigators who were not involved with patient care reviewed the clinical and imaging records. The reported outcomes were as assessed at the time of the last follow-up, unless otherwise stated. RESULTS The preservation of preoperative Class A hearing status was achieved in 14.3% of MS cases compared with 42.9% of SRS cases (OR 4.5; p < 0.05) after an average follow-up interval of 43.7 months and 30.3 months, respectively. Serviceable hearing was preserved in 42.8% of MS cases compared with 85.7% of SRS cases (OR 8.0; p < 0.01). The rates of postoperative CN VII dysfunction were low for both groups, although significantly higher in the MS group (HB III-IV 11% vs 0% for SRS; OR 21.3; p < 0.01) at a median follow-up interval of 35.7 and 19.0 months for MS and SRS, respectively. There was no difference in the need for subsequent intervention (2 MS patients and 2 SRS patients). CONCLUSIONS At this high-volume center, VS resection or radiosurgery for tumors ≤ 2.8 cm in diameter was associated with low overall morbidity. The need for subsequent intervention was the same in both groups. SRS was associated with improved hearing and facial preservation rates and reduced morbidity, but with a shorter average follow-up period. Facial function was excellent in both groups. Since patients were not randomly selected for surgery, different clinical outcomes may be of different value to individual patients. Both anticipated medical outcomes and patient goals remain the drivers of treatment decisions.

Prevalence of degenerative changes of the atlanto-axial joints.

BACKGROUND CONTEXT: Degeneration of the atlantodens and atlanto-axial joints is associated with cervical spine pain and may also be associated with an increased risk of dens fracture. However, there is paucity of literature describing the prevalence of specific degenerative changes in the atlantodens and atlanto-axial facet joints. PURPOSE: To document age-related degenerative changes of the cervical spine in a large cohort of patients. STUDY DESIGN/SETTING: This is a retrospective cohort study. PATIENT SAMPLE: Adult trauma patients were admitted to our Level 1 trauma center. OUTCOME MEASURES: Osteoarthritis of the atlantodens and atlanto-axial facet joints of the cervical spine and the presence of intraosseous cyst and calcific synovitis, as determined by computed tomography (CT) scans. METHODS: We conducted a retrospective study of 1,543 adult trauma patients who received a cervical spine CT scan. The anterior atlantodens joint interval was measured. The presence or absence of intraosseous cysts and calcific synovitis was recorded. Degeneration of the atlantodens and atlanto-axial facet joints at age intervals was quantified. RESULTS: The atlantodens interval narrowed linearly with age (R(2)=0.992, p<.001). The prevalence of intraosseous cysts increased exponentially with age from 4.2% to 37.4%, and calcific synovitis increased from 0% to 11.1%. Intraosseous cyst formation generally began in the second and third decades of life and synovitis in the fifth and sixth decades of life. Facet joints also demonstrated age-related changes; however, the rate of degenerative changes was lower than in the atlantodens joint. CONCLUSIONS: To our knowledge, this is the first study that documents specific changes of both atlantodens and atlanto-axial facet joints as a function of age in a large cohort of 1,543 patients. These changes increased exponentially with age and may contribute to pain and limitation in motion. In light of our findings and recent studies demonstrating the association between degeneration and dens fracture in elderly, cervical spine radiographs of elderly patients should be carefully assessed for these changes.

Association between advanced degenerative changes of the atlanto-dens joint and presence of dens fracture.

BACKGROUND: Dens fractures in elderly patients are often related to issues associated with aging. We examined the association between degenerative changes of the atlanto-dens joint and the risk of dens fracture. METHODS: We conducted a retrospective study of trauma patients, fifty-five years of age or older, who had undergone a computed tomography scan of the cervical spine as part of their admission to a single level-I trauma center. There were 1794 patients who met the inclusion criteria; scans were evaluated for all fifty-six who presented with a dens fracture and for a random sample of 736 without a dens fracture. Intraosseous cyst formation, synovitis, and joint space narrowing were recorded from the scans. The prevalence of degenerative changes was compared between patients with and patients without a dens fracture. RESULTS: An intraosseous cyst in the dens was found in 16.4% of the patients without a dens fracture and in 64.3% of those with a fracture (p < 0.001). The dens fracture extended through the existing cyst in twenty-four (66.7%) of thirty-six patients with a cyst and a dens fracture. Retro-dens synovitis was present in 4.2% of the patients without a dens fracture and 25.0% of those with a fracture (p < 0.001). After adjustment for age and sex, both cysts (odds ratio [OR] = 7.7, 95% confidence interval [CI] = 4.2 to 14.1) and synovitis (OR = 4.6, 95% CI = 2.1 to 10.0) were significantly associated with dens fracture. CONCLUSIONS: Intraosseous dens cysts and retro-dens synovitis were associated with dens fracture; those with a dens fracture were nearly eightfold more likely to have an intraosseous cyst and nearly fivefold more likely to have synovitis compared with those without a dens fracture. Because the atlanto-dens joint is a synovial joint, its degeneration can lead to subchondral cyst formation and synovitis and predispose affected individuals to fracture.

Cognitive deficits and delayed neuronal loss in a mouse model of multiple microinfarcts.

Microinfarcts are a common clinical feature of the aging brain, particularly in patients with cognitive decline or vascular or Alzheimer's dementia. However, the natural history of these lesions remains largely unexplored. Here we describe a mouse (C57BL/6J) model of multiple diffuse microinfarcts induced by unilateral internal carotid artery injection of cholesterol crystals (40-70 µm). Microinfarcts were spread throughout the deep cortex, subcortical tissue, and hippocampus and were comprised of a core positive for CD68 (a marker for reactive microglia and macrophages), surrounded by large regions of glial fibrillary acidic protein-positive reactive astrogliosis. Widespread reactive gliosis, including mislocalization of the astrocytic water channel aquaporin 4 persisted long after injury, recovering only after 1 month after stroke. Within the cortex, neuronal cell death progressed gradually over the first month, from ∼35% at 3 d to 60% at 28 d after stroke. Delayed demyelination was also observed in lesions, beginning 28 d after stroke. These findings demonstrate that microinfarct development follows a distinct course compared to larger regional infarcts such as those induced by middle cerebral artery occlusion. The long-lasting gliosis, delayed neuronal loss, and demyelination suggest that the therapeutic window for microinfarcts may be much wider (perhaps days to weeks) than for larger strokes.