bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlation of personality assessments with standard selection criteria for neurosurgical residency applicants
Authors: Lubelski Daniel , Healy Andrew T. , Friedman Alan , Ferraris Dyan , Benzel Edward C. , Schlenk Richard 
Published: February 2016

OBJECTIVE
Neurosurgery is among the most competitive residencies, as evidenced by the high number of applicants for relatively few positions. Although it is important to recruit candidates who have the intellectual capacity and drive to succeed, traditional objective selection criteria, such as US Medical Licensing Examination (USMLE) (also known as Step 1) score, number of publications, and class ranking, have not been shown to consistently predict clinical and academic success. Furthermore, these traditional objective parameters have not been associated with specific personality traits.

METHODS
The authors sought to determine the efficacy of a personality assessment in the selection of neurosurgery residents. Specifically, the aim was to determine the correlation between traditional measures used to evaluate an applicant (e.g., USMLE score, number of publications, MD/PhD status) and corresponding validated personality traits.

RESULTS
Fifty-four neurosurgery residency applicants were interviewed at the Cleveland Clinic during the 2014–2015 application cycle. No differences in validated personality scores were identified between the 46 MD applicants and 8 MD/PhD applicants. The mean USMLE score (± SD) was 252.3 ± 11.9, and those in the high-USMLE-score category (USMLE score ≥ 260) had a significantly lower “imaginative” score (a stress measure of eccentric thinking and impatience with those who think more slowly). The average number of publications per applicant was 8.6 ± 7.9, and there was a significant positive correlation (r = 0.339, p = 0.016) between greater number of publications and a higher “adjustment” score (a measure of being even-tempered, having composure under pressure). Significant negative correlations existed between the total number of publications and the “excitable” score (a measure of being emotionally volatile) (r = −0.299, p = 0.035) as well as the “skeptical” score (measure of being sensitive to criticism) (r = −0.325, p = 0.021). The average medical school rank was 25.8, and medical school rankings were positively correlated with the “imaginative” score (r = 0.287, p = 0.044).

CONCLUSIONS
This is the first study to investigate the use of personality scores in the selection of neurosurgical residents. The use of personality assessments has the potential to provide insight into an applicant's future behavior as a resident and beyond. This information may be useful in the selection of neurosurgical residents and can be further used to customize the teaching of residents and for enabling them to recognize their own strengths and weaknesses for self-improvement.
Comparative analysis of the anterior transpetrosal approach with the endoscopic endonasal approach to the petroclival region
Authors: Muto Jun , Prevedello Daniel M. , Ditzel Filho Leo F. S. , Tang Ing Ping , Oyama Kenichi , Kerr Edward E. , Otto Bradley A. , Kawase Takeshi , Yoshida Kazunari , Carrau Ricardo L. 
Published: February 2016

OBJECTIVE
The endoscopic endonasal approach (EEA) offers direct access to midline skull base lesions, and the anterior transpetrosal approach (ATPA) stands out as a method for granting entry into the upper and middle clival areas. This study evaluated the feasibility of performing EEA for tumors located in the petroclival region in comparison with ATPA.

METHODS
On 8 embalmed cadaver heads, EEA to the petroclival region was performed utilizing a 4-mm endoscope with either 0° or 30° lenses, and an ATPA was performed under microscopic visualization. A comparison was executed based on measurements of 5 heads (10 sides). Case illustrations were utilized to demonstrate the advantages and disadvantages of EEA and ATPA when dealing with petroclival conditions.

RESULTS
Extradurally, EEA allows direct access to the medial petrous apex, which is limited by the petrous and paraclival internal carotid artery (ICA) segments laterally. The ATPA offers direct access to the petrous apex, which is blocked by the petrous ICA and abducens nerve inferiorly. Intradurally, the EEA allows a direct view of the areas medial to the cisternal segment of cranial nerve VI with limited lateral exposure. ATPA offers excellent access to the cistern between cranial nerves III and VIII. The quantitative analysis demonstrated that the EEA corridor could be expanded laterally with an angled drill up to 1.8 times wider than the bone window between both paraclival ICA segments.

CONCLUSIONS
The midline, horizontal line of the petrous ICA segment, paraclival ICA segment, and the abducens nerve are the main landmarks used to decide which approach to the petroclival region to select. The EEA is superior to the ATPA for accessing lesions medial or caudal to the abducens nerve, such as chordomas, chondrosarcomas, and midclival meningiomas. The ATPA is superior to lesions located posterior and/or lateral to the paraclival ICA segment and lesions with extension to the middle fossa and/or infratemporal fossa. The EEA and ATPA are complementary and can be used independently or in combination with each other in order to approach complex petroclival lesions.
Radical treatment for bilateral vertebral artery dissecting aneurysms by reconstruction of the vertebral artery
Authors: Ota Nakao , Tanikawa Rokuya , Eda Hirotake , Matsumoto Takashi , Miyazaki Takanori , Matsukawa Hidetoshi , Yanagisawa Takeshi , Suzuki Go , Miyata Shiro , Oda Jumpei , Noda Kosumo , Tsuboi Toshiyuki , Takeda Rihei , Kamiyama Hiroyasu , Tokuda Sadahisa 
Published: February 2016

OBJECTIVE
Bilateral vertebral artery dissecting aneurysms (VADAs) have a poor prognosis because progressive enlargement of the aneurysms compresses the brainstem or causes subarachnoid hemorrhage. The trapping of 1 vertebral artery (VA) places increased hemodynamic stress on the contralateral VA and may lead to enlargement and rupture. Therefore, management strategies are controversial. This study describes a radical treatment for bilateral VADAs using bypass surgery.

METHODS
Seven patients with bilateral VADAs were included. Three patients were treated by trapping of 1 VA via coiling or clipping at another hospital; the previously treated VA in 1 patient and the contralateral untreated VA in 2 patients subsequently enlarged. The other 4 patients presented without previous intervention and progressive enlargement of the aneurysms.

RESULTS
The post–coil embolization patients underwent V3–posterior cerebral artery (PCA) bypass and trapping. The other 4 patients underwent VA reconstruction via V3–V4 or V4–V4 bypass, with contralateral trapping on a separate day in 3 patients and observation in 1 patient. Perioperative complications included 1 case of cerebrospinal fluid leakage for which the patient required an additional operation, 1 case of dysphagia and facial palsy due to sigmoid sinus thrombosis, and 1 case of dysphagia. The long-term outcomes of these patients were favorable.

CONCLUSIONS
Patients with bilateral VADAs require treatment on both sides. If VA trapping is performed first, the treatment options for the other side are limited to V3-PCA bypass and trapping. This procedure is effective; however, it is also invasive and technically difficult. In cases of bilateral VADAs in which it is feasible to reconstruct 1 side, the best approach is to begin by reconstructing the VA that appears technically easiest, followed by trapping of the contralateral VADA. This strategy allows enough time to suture vessels because contralateral reverse flow is maintained.
Diffusion tensor imaging assessment of microstructural brainstem integrity in Chiari malformation Type I
Authors: Krishna Vibhor , Sammartino Francesco , Yee Philip , Mikulis David , Walker Matthew , Elias Gavin , Hodaie Mojgan 
Published: February 2016

OBJECTIVE
The diagnosis of Chiari malformation Type I (CM-I) is primarily based on the degree of cerebellar tonsillar herniation even though it does not always correlate with symptoms. Neurological dysfunction in CM-I presumably results from brainstem compression. With the premise that conventional MRI does not reveal brain microstructural changes, this study examined both structural and microstructural neuroimaging metrics to distinguish patients with CM-I from age- and sex-matched healthy control subjects.

METHODS
Eight patients with CM-I and 16 controls were analyzed. Image postprocessing involved coregistration of anatomical T1-weighted with diffusion tensor images using 3D Slicer software. The structural parameters included volumes of the posterior fossa, fourth ventricle, and tentorial angle. Fractional anisotropy (FA) was calculated separately in the anterior and posterior compartments of the lower brainstem.

RESULTS
The mean age of patients in the CM-I cohort was 42.6 ± 10.4 years with mean tonsillar herniation of 12 mm (SD 0.7 mm). There were no significant differences in the posterior fossa volume (p = 0.06) or fourth ventricular volume between the 2 groups (p = 0.11). However, the FA in the anterior brainstem compartment was significantly higher in patients with CM-I preoperatively (p = 0.001). The FA values normalized after Chiari decompression except for persistently elevated FA in the posterior brainstem compartment in patients with CM-I and syrinx.

CONCLUSIONS
In this case-control study, microstructural alterations appear to be reliably associated with the diagnosis of CM-I, with a significantly elevated FA in the lower brainstem in patients with CM-I compared with controls. More importantly, the FA values normalized after decompressive surgery. These findings should be validated in future studies to determine the significance of diffusion tensor imaging–based assessment of brainstem microstructural integrity as an adjunct to the clinical assessment in patients with CM-I.
Myelopathic signs and functional outcome following cervical decompression surgery: a proposed myelopathy scale
Authors: El-Zuway Salem , Farrokhyar Forough , Kachur Edward 
Published: February 2016

OBJECTIVE
Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction in adults. In spite of this, the impact of the changes in myelopathic signs following cervical decompression surgery and their relationship to functional outcome measures remains unclear. The main goals of our study were to prospectively assess changes in myelopathic signs with a functional outcome scale (the modified Japanese Orthopaedic Association [mJOA] scale) following cervical decompression surgery and to objectively test a proposed new myelopathy scale (MS).

METHODS
Between 2008 and 2011, 36 patients with CSM were observed following cervical decompression surgery. Patient data including mJOA and MS scores were prospectively collected and analyzed preoperatively and at 1 year after surgery.

RESULTS
In this cohort, reflex, Babinski, and proprioception signs showed statistically significant improvement following surgery at 1 year (p = < 0.001, p = 0.008, and p = 0.015, respectively). A lesser degree of improvement was observed with the Hoffman sign (p = 0.091). No statistically significant improvement in clonus occurred (p = 0.368). There was a significant improvement in mJOA (p ≤ 0.001) and MS (p ≤ 0.001) scores at 1 year compared with the preoperative scores. The results showed an inverse correlation between MS and mJOA scores both pre- and postoperatively (Spearman's correlation coefficient = −0.202 preoperatively and −0.361 postoperatively).

CONCLUSIONS
Improvement in myelopathic signs was noted following cervical decompression surgery in patients with CSM. The newly devised MS scale demonstrated these findings, and the new MS scale correlates with improvement in mJOA scores in this patient cohort.
A review of the cellular and molecular effects of extracorporeal shockwave therapy
Authors: Chamberlain Georgina , Colborne Robert 
Published: February 2016

SummaryExtracorporeal shockwave therapy (ESWT) is a novel therapeutic modality and its use in promoting connective tissue repair and analgesic effect has been advocated in the literature. It is convenient, cost-effective, and has negligible complications; it therefore bypasses many of the problems associated with surgical interventions. This paper reviews the proposed mechanisms of action in promoting tissue repair and regeneration as well as analysing its efficacy providing an analgesic effect in clinical applications. Further research will be required to not only identify the underlying mechanisms more precisely, but will also be critical for ensuring consistency across the literature so that the most beneficial treatment protocol can be developed. Extracorporeal shockwave therapy stands as a promising alternative modality in promoting tissue repair.
Short and long-term outcome following surgical stabilization of tarsocrural instability in dogs
Authors: Beever Lee , Kulendra Elvin , Meeson Richard 
Published: February 2016

SummaryObjectives: To evaluate the outcome and complications following surgical stabilization of canine tarsocrural luxations.Methods: Medical records of dogs which were surgically treated for tarsocrural joint instability between February 2007 and June 2014 were reviewed. Surgical technique, complications and long-term outcome (via questionnaire and Canine Brief Pain Inventory) were assessed.Results: Twenty-four dogs (26 joints) were included. All injuries were traumatic. All joints had associated fractures; malleolar in 21/26 limbs (13/26 medial). Eight joints had internal fracture fixation and transarticular external skeletal fixator, six had external fixator alone, four had prosthetic ligaments with external fixator, and four had prosthetic ligaments with external coaptation. Two joints had pantarsal arthrodesis and two primary ligament repair. Complications occurred in 24/26 limbs giving 45 distinct complications; 16 were minor, 29 major, and 31 complications were external fixator associated. Prosthetic ligaments were significantly associated with major complications (p = 0.017); five out of eight required subsequent removal between 105–1006 days. Cost was significantly associated with major complications (p = 0.017) and soft tissue wounds (p = 0.03). Long-term lameness was seen in nine of 14 dogs. There was no association between pain severity (p = 0.3) and pain interference scores (p = 0.198) when comparing stabilization methods.Clinical significance: Complications are common; however many are external fixator related. Prosthetic ligaments are significantly associated with major complications. Regardless of technique, a degree of ongoing lameness is likely.
Assessment of a computed tomography guided injection technique of the lumbo-sacral disc in sheep
Authors: Neveu Fabienne , Vandeweerd Jean-Michel , Kirschvink Nathalie , Nozry Kadhija , Gustin Pascal , Dugdale Alex , Bihin Benoît , Nisolle Jean-François 
Published: February 2016

Summary
Objectives: Recent data indicate that degeneration of intervertebral discs occurs naturally in sheep, with a higher prevalence at the level of the lumbo-sacral disc. The objective of this ex vivo study was to evaluate a computed tomography (CT) guided method of injection into the ovine lumbo-sacral disc.
Methods: Six euthanatized sheep were used for identification of the approach plane, the optimal direction of the needle and the mean distance from skin to disc. Dissection after injection of coloured ink was used to determine the anatomical structures that were penetrated. In seven other animals, all spines were assessed beforehand by CT and magnetic resonance imaging to determine whether disc pathology was present. The final position of the needle was assessed by CT to determine the accuracy of the technique. Contrast agent was injected to identify any problems associated with administration of liquid into the disc.
Results: The CT guided injection technique was easy to perform and enabled adequate positioning of the needle into all (n = 7) lumbo-sacral discs. Distance between the skin and the disc ranged between 12 and 17 cm. No organ, vascular or nervous structure was penetrated and the needle path remained intramuscular without penetration of the peritoneal cavity. Contrast medium leaked out through three degenerate discs.
Clinical significance: The current study described a consistently safe and accurate CT guided injection technique to the lumbo sacral disc for future in vivo experimental studies that will use sheep as animal model for human intervertebral disc disease disease.
Is Adapted APD Theoretically More Efficient than Conventional APD?
Authors: Öberg Carl M. , Rippe Bengt 
Published: February 2016

Background A modified version of automated peritoneal dialysis (APD) using not only variable dwell times but also variable fill volumes has been tested against conventional APD (cAPD) with fixed dwell volumes in a randomized controlled clinical study. The results have indicated that the modified schedule for APD, denoted adapted APD (aAPD), can lead to improved small solute clearances, and, above all, a markedly increased sodium removal (NaR). To theoretically test these results, we have modeled aAPD vs cAPD in computer simulations using the 3-pore model (TPM). Methods The TPM, modified by including a transient, initial inflation of small solute mass transfer area coefficients (PS values), was employed. For simulations of osmotic ultrafiltration (UF), the TPM uses a constantly inflated value for PS for glucose and also a reduced value for PS for Na+, setting the peritoneal lymphatic reabsorption term at 0.3 mL/min. The simulations were performed by assuming that increases in intraperitoneal hydrostatic pressure (IPP) are transmitted to the capillary level ( via vein compression) and therefore do not significantly affect the Starling balance. Furthermore, the effective peritoneal surface area (A) was set to be variable as a function of intraperitoneal volume (IPV). Results The simulations demonstrated a minor improvement of small solute clearances (∼0.7 – 1.6%) and a very small improvement of UF and NaR in aAPD compared to cAPD. Conclusions Due mainly to the increased fill volumes in 3 out of 5 dwells in aAPD, this modality caused minor increases in small solute clearances and marginal effects on UF and NaR. The computer simulations point to a need for accurate sodium determinations in aAPD, considering all the methodological problems and pitfalls relevant to determining dialysate Na+ concentrations and peritoneal sodium mass balance.
Older Age, Higher Body Mass Index and Inflammation Increase the Risk for New-Onset Diabetes and Impaired Glucose Tolerance in Patients on Peritoneal Dialysis?
Authors: Dong Jie , Yang Zhi-kai , Chen Yuan 
Published: February 2016

Objectives To identify predictors of new-onset diabetes and impaired glucose tolerance (IGT) events in patients undergoing peritoneal dialysis (PD) based on baseline and time-dependent covariates, respectively. Methods In this prospective, single center-based cohort, all non-diabetic incident PD patients between August 2003 and August 2011 were included. All demographic and laboratory data were recorded at baseline. Repeated measurements for laboratory, dialysis prescription, and nutrition parameters were recorded at regular intervals. Multivariable Cox regression models built from baseline and time-dependent variables respectively were used to calculate the hazard ratio (HR) of potential predictors for new-onset diabetes and IGT (NODI). Results Of the 612 PD patients, 25 (4.1%) and 7 (1.1%) patients were identified with NODI, respectively, during a mean follow-up period of 32.4 (12.9 – 60.8) months. Using multivariable Cox regression analysis, age and body mass index (BMI) at baseline were significantly associated with NODI after adjustment for potential confounders. During follow-up, time-dependent BMI and serum high-sensitive C-reactive protein (HS-CRP) independently predicted the risk for NODI. Patients with NODI had significantly elevated plasma glucose concentrations and BMI from the start of PD therapy, with serum HS-CRP maintained at high levels. Dietary/dialysate energy intake and other laboratory parameters were not correlated with NODI risk either as baseline or time-dependent variables. Conclusions Traditional and uremic-related risk factors, such as older age, higher BMI, and inflammation, contribute to new-onset diabetes and impaired glucose tolerance in PD patients.
EVIDENCE THAT HYDRA I IS A TIDALLY DISRUPTING MILKY WAY DWARF GALAXY
Authors: Hargis Jonathan R. , Kimmig Brian , Willman Beth , Caldwell Nelson , Walker Matthew G. , Strader Jay , Sand David J. , Grillmair Carl J. , Yoon Joo Heon 
Published: February 2016

ABSTRACT
The Eastern Banded Structure (EBS) and Hydra I halo overdensities are very nearby (d ∼ 10 kpc) objects discovered in Sloan Digital Sky Survey (SDSS) data. Previous studies of the region have shown that EBS and Hydra I are spatially coincident, cold structures at the same distance, suggesting that Hydra I may be the EBS's progenitor. We combine new wide-field Dark Energy Camera (DECam) imaging and MMT/Hectochelle spectroscopic observations of Hydra I with SDSS archival spectroscopic observations to quantify Hydra I's present-day chemodynamical properties, and to infer whether it originated as a star cluster or dwarf galaxy. While previous work using shallow SDSS imaging assumed a standard old, metal-poor stellar population, our deeper DECam imaging reveals that Hydra I has a thin, well-defined main sequence turnoff of intermediate age (∼5–6 Gyr) and metallicity ([Fe/H] = −0.9 dex). We measure statistically significant spreads in both the iron and alpha-element abundances of

dex and

dex, respectively, and place upper limits on both the rotation and its proper motion. Hydra I's intermediate age and [Fe/H]—as well as its low [α/Fe], apparent [Fe/H] spread, and present-day low luminosity—suggest that its progenitor was a dwarf galaxy, which has subsequently lost more than 99.99% of its stellar mass.
A GRANULATION “FLICKER”-BASED MEASURE OF STELLAR SURFACE GRAVITY
Authors: Bastien Fabienne A. , Stassun Keivan G. , Basri Gibor , Pepper Joshua 
Published: February 2016

ABSTRACT
In our previous work we found that high-quality light curves, such as those obtained by Kepler, may be used to measure stellar surface gravity via granulation-driven light curve “flicker” (F
8). Here, we update and extend the relation originally presented by Bastien et al. in 2013 after calibrating F
8 against a more robust set of asteroseismically derived surface gravities. We describe in detail how we extract the F
8 signal from the light curves, including how we treat phenomena, such as exoplanet transits and shot noise, that adversely affect the measurement of F
8. We examine the limitations of the technique, and, as a result, we now provide an updated treatment of the F
8-based

error. We briefly highlight further applications of the technique, such as astrodensity profiling or its use in other types of stars with convective outer layers. We discuss potential uses in current and upcoming space-based photometric missions. Finally, we supply F
8-based

values, and their uncertainties, for 27,628 Kepler stars not identified as hosts of transiting planets, with 4500 K < T
eff < 7150 K, 2.5 <

< 4.6, K

p
≤ 13.5, and overall photometric amplitudes <10 parts per thousand.