bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical and methodological precision of spinal navigation assisted by 3D intraoperative O-arm radiographic imaging
Authors: Oertel Matthias F. , Hobart Juliane , Stein Marco , Schreiber Vanessa , Scharbrodt Wolfram 
Published: January 2011

Object
In recent years, the importance of intraoperative navigation in neurosurgery has been increasing. Multiple studies have proven the advantages and safety of computer-assisted spinal neurosurgery. The use of intraoperative 3D radiographic imaging to acquire image information for navigational purposes has several advantages and should increase the accuracy and safety of screw guidance with navigation. The aim of this study was to evaluate the clinical and methodological precision of navigated spine surgery in combination with the O-arm multidimensional imaging system.

Methods
Thoracic, lumbar, and sacral pedicle screws that were placed with the help of the combination of the O-arm and StealthStation TREON plus navigation systems were analyzed. To evaluate clinical precision, 278 polyaxial pedicle screws in 139 vertebrae were reviewed for medial or caudal perforations on coronal projection. For the evaluation of the methodological accuracy, virtual and intraoperative images were compared, and the angulation of the pedicle screw to the midsagittal line was measured.

Results
Pedicle perforations were recorded in 3.2% of pedicle screws. None of the perforated pedicle screws damaged a nerve root. The difference in angulation between the actual and virtual pedicle screws was 2.8° ± 1.9°.

Conclusions
The use of the StealthStation TREON plus navigation system in combination with the O-arm system showed the highest accuracy for spinal navigation compared with other studies that used traditional image acquisition and registration for navigation.
Magnetic resonance imaging findings in treated spinal dural arteriovenous fistulas: lack of correlation with clinical outcomes
Authors: Kaufmann Timothy J. , Morris Jonathan M. , Saladino Andrea , Mandrekar Jay N. , Lanzino Giuseppe 
Published: January 2011

Object
Little information is available on follow-up MR imaging after treatment of spinal dural arteriovenous fistulas (DAVFs). The authors studied MR imaging findings in treated spinal DAVFs in relation to clinical outcomes.

Methods
A retrospective review of patients with spinal DAVFs who had undergone both pre- and postoperative spinal MR imaging was conducted. Postoperative MR images were obtained as routine follow-up studies or because of subjective or objective clinical deterioration. Several pre- and posttreatment MR imaging characteristics were evaluated by 2 neuroradiologists blinded to the clinical outcome. Clinical outcomes of motor, sensory, and urinary function (in relation to the patient's preoperative status) at the time of the postoperative MR imaging were obtained from the clinical record. The chi-square, Fisher exact, and rank-sum tests were performed to correlate imaging findings and changes with clinical outcomes.

Results
Thirty-four patients met inclusion criteria. Treatment was surgical in 33 patients and endovascular in 1 patient. Follow-up MR imaging was performed at a mean 168 ± 107 days after treatment. Twenty-seven patients (79.4%) were either clinically stable or improved, and 7 (20.6%) experienced worsening in one or more clinical outcomes. Most patients were found to have improvement of MR imaging changes. However, some degree of persistent spinal cord signal abnormality, enhancement, and swelling was observed in 31 (91.2%), 29 (85.3%), and 18 (52.3%) patients, respectively. Changes in these MR imaging characteristics compared with preoperative MR imaging did not correlate with clinical outcomes (p > 0.05), with the one exception of a significant correlation between change in urinary function and extent of spinal cord contrast enhancement (p = 0.026), a correlation of uncertain importance. Ten of the 34 patients underwent posttreatment digital subtraction angiography, and 3 of these patients had recurrent/residual DAVFs. Worsening of motor function significantly correlated with recurrent/residual DAVF (p = 0.053).

Conclusions
Spinal cord abnormalities persist on postoperative MR imaging studies in patients with treated spinal DAVFs, and although they tend to mildly improve with time, these changes may not correlate with clinical outcomes. However, regardless of imaging findings, worsening motor function may correlate with a recurrent or residual DAVF.
Does alendronate disturb the healing process of posterior lumbar interbody fusion? A prospective randomized trial
Authors: Nagahama Ken , Kanayama Masahiro , Togawa Daisuke , Hashimoto Tomoyuki , Minami Akio 
Published: January 2011

Object
Bisphosphonate medications are widely used for the treatment of osteoporosis, but they might disturb the healing process of spinal fusion. The object of this prospective randomized controlled study was to evaluate the effect of bisphosphonate medication on spinal fusion through radiographic, clinical, and biological assessments.

Methods
A total of 40 patients with osteoporosis who were candidates for single-level posterior lumbar interbody fusion were randomly assigned to the alendronate group (alendronate sodium 35 mg/week) or the control group (vitamin D, alfacalcidol 1 μg/day). Pedicle screw fixation and carbon polyetheretherketone cages were used for all the patients. Bone graft material was prepared as a mixture of local bone and β-tricalcium phosphate in a ratio of 2:1. Functional radiography and CT scans were used to evaluate fusion status and cage subsidence. The incidence of vertebral compression fractures (VCFs) occurring after surgery (subsequent VCFs) was assessed by means of MR imaging. Bridging bone formation was graded into 3 categories: Grade A (bridging bone through bilateral cages), Grade B (bridging bone through a unilateral cage), or Grade C (incomplete bony bridging). A solid fusion was defined as less than 5° of angular motion in flexion-extension radiographs and the presence of bridging bone through the cage (Grade A or B). Clinical outcome was evaluated by means of the Oswestry Disability Index. Bone metabolic markers (serum bone alkaline phosphatase, serum and urine Type I collagen cross-linked N-telopeptides) were measured to investigate the biological effects of alendronate on spinal fusion.

Results
Bridging bone formation (Grade A or B) was more frequently observed in the alendronate group at all postoperative assessment periods. At 1-year postoperative follow-up, a solid fusion was achieved in 95% of the patients in the alendronate group and 65% of those in the control group. Cage subsidence (> 2 mm) was observed in 5% of the alendronate group and 29% of the control group. No vertebral fractures were observed in the alendronate group, whereas 24% of patients in the control group showed subsequent VCFs. There was no statistically significant between-groups difference in clinical outcomes, but poor clinical results in the control group were associated with pseudarthrosis and subsequent VCFs. Biochemical analysis of bone turnover demonstrated that alendronate inhibited bone resorption from the early phase of the fusion process and also suppressed bone formation after 6 months postoperatively.

Conclusions
Favorable mechanical circumstances provided by alendronate overcame its detrimental biological effect on the healing process of spinal fusion. The authors recommend that osteoporosis patients undergoing spinal fusion take bisphosphonates throughout the postoperative period.
Delayed postoperative hemorrhage in 21 patients with intracranial epidermoid cysts
Authors: Ren Xiao-hui , Chu Chun , Zeng Chun , Tian Yong-ji , Ma Zhen-yu , Tang Kai , Yu Lan-bing , Cui Xiang-li , Wang Zhong-cheng , Lin Song 
Published: January 2011

Object
Intracranial epidermoid cysts are rare, potentially curable, benign lesions that are sometimes associated with severe postoperative complications, including hemorrhage. Delayed hemorrhage, defined as one that occurred after an initial unremarkable postoperative CT scan, contributed to most cases of postoperative hemorrhage in patients with epidermoid cyst. In this study, the authors focus on delayed hemorrhage as one of the severe postoperative complications in epidermoid cyst, report its incidence and its clinical features, and analyze related clinical parameters.

Methods
There were 428 cases of intracranial epidermoid cysts that were surgically treated between 2002 and 2008 in Beijing Tiantan Hospital, and these were retrospectively reviewed. Among them, the cases with delayed postoperative hemorrhage were chosen for analysis. Clinical parameters were recorded, including the patient's age and sex, the chief surgeon's experience in neurosurgery, the year in which the operation was performed, tumor size, adhesion to neurovascular structures, and degree of resection. These parameters were compared in patients with and without delayed postoperative hemorrhage to identify risk factors associated with this entity.

Results
The incidences of postoperative hemorrhage and delayed postoperative hemorrhage in patients with epidermoid cyst were 5.61% (24 of 428) and 4.91% (21 of 428), respectively, both of which were significantly higher than that of postoperative hemorrhage in all concurrently treated intracranial tumors, which was 0.91% (122 of 13,479). The onset of delayed postoperative hemorrhage ranged from the 5th to 23rd day after the operation; the median time of onset was the 8th day. The onset manifestation included signs of intracranial hypertension and/or meningeal irritation (71.4%), brain herniation (14.3%), seizures (9.5%), and syncope (4.8%). Neuroimages revealed hematoma in 11 cases and subarachnoid hemorrhage in 10 cases. The rehemorrhage rate was 38.1% (8 of 21). The mortality rate for delayed postoperative hemorrhage was 28.6% (6 of 21). None of the clinical parameters was correlated with delayed postoperative hemorrhage (p > 0.05), despite a relatively lower p value for adhesion to neurovascular structures (p = 0.096).

Conclusions
Delayed postoperative hemorrhage contributed to most of the postoperative hemorrhages in patients with intracranial epidermoid cysts and was a unique postoperative complication with unfavorable outcomes. Adhesion to neurovascular structures was possibly related to delayed postoperative hemorrhage (p = 0.096).
Vertebral artery pexy for microvascular decompression of the facial nerve in the treatment of hemifacial spasm
Authors: Ferreira Manuel , Walcott Brian P. , Nahed Brian V. , Sekhar Laligam N. 
Published: January 2011

Object
Hemifacial spasm (HFS) is caused by arterial or venous compression of cranial nerve VII at its root exit zone. Traditionally, microvascular decompression of the facial nerve has been an effective treatment for posterior inferior and anterior inferior cerebellar artery as well as venous compression. The traditional technique involves Teflon felt or another construct to cushion the offending vessel from the facial nerve, or cautery and division of the offending vein. However, using this technique for severe vertebral artery (VA) compression can be ineffective and fraught with complications. The authors report the use of a new technique of VA pexy to the petrous or clival dura mater in patients with HFS attributed to a severely ectatic and tortuous VA, and detail the results in a series of patients.

Methods
Six patients with HFS due to VA compression underwent a retrosigmoid craniotomy, combined with a far-lateral approach in some patients. On identification of the site of VA compression, the vessel was mobilized adequately for the decompression. Great care was taken to avoid kinking the perforating vessels arising from the VA. Two 8-0 nylon sutures were passed through to the wall of the VA and then through the clival or petrous dura, and then tied to alleviate compression on cranial nerve VII.

Results
Patients were followed for at least 1 year postoperatively (mean 2.7 years, range 1–4 years). All 6 patients had complete resolution of their HFS. Facial function was tested postoperatively, and was stable when compared with the preoperative baseline. Two of the 3 patients with preoperative tinnitus had resolution of this symptom after the procedure. Postoperative imaging demonstrated VA decompression of the facial nerve and no evidence of stroke in all patients. One patient suffered from hearing loss, another developed a postoperative transient unilateral vocal cord paralysis, and a third patient developed a pseudomeningocele that resolved with the placement of a lumbar drain.

Conclusions
Hemifacial spasm and other neurovascular syndromes are effectively treated by repositioning the compressing artery. Careful study of the preoperative MR images may identify a select group of patients with HFS due to an ectatic VA. Rather than traditional decompression with only pledget placement, these patients may benefit from a VA pexy to provide an effective, safe, and durable resolution of their symptoms while minimizing surgical complications.
Ventricle wall movements and cerebrospinal fluid flow in hydrocephalus
Authors: Penn Richard D. , Basati Sukhraaj , Sweetman Brian , Guo Xiaodong , Linninger Andreas 
Published: January 2011

Object
The dynamics of fluid flow in normal pressure hydrocephalus (NPH) are poorly understood. Normally, CSF flows out of the brain through the ventricles. However, ventricular enlargement during NPH may be caused by CSF backflow into the brain through the ventricles. A previous study showed this reversal of flow; in the present study, the authors provide additional clinical data obtained in patients with NPH and supplement these data with computer simulations to better understand the CSF flow and ventricular wall displacement and emphasize its clinical implications.

Methods
Three NPH patients and 1 patient with aqueductal stenosis underwent cine phase-contrast MR imaging (cine MR imaging) for measurement of CSF flow and ventricle wall movement during the cardiac cycle. These data were compared to data previously obtained in 8 healthy volunteers.
The CSF flow measurements were obtained at the outlet of the aqueduct of Sylvius. Calculation of the ventricular wall movement was determined from the complete set of cine MR images obtained axially at the middle of the lateral ventricle. The data were obtained before and after CSF removal with a ventriculoperitoneal shunt with an adjustable valve. To supplement the clinical data, a computational model was used to predict the transmural pressure and flow.

Results
In healthy volunteers, net CSF aqueductal flow was 1.2 ml/minute in the craniocaudal direction. In patients with NPH, the net CSF flow was in the opposite direction—the caudocranial direction—before shunt placement. After shunting, the magnitude of the abnormal fluid flow decreased or reversed, with the flow resembling the normal flow patterns observed in healthy volunteers.

Conclusions
The authors' MR imaging–based measurements of the CSF flow direction and lateral ventricle volume size change and the results of computer modeling of fluid dynamics lead them to conclude that the directional pattern and magnitude of CSF flow in patients with NPH may be an indication of the disease state. This has practical implications for shunt design and understanding the mechanisms that produce hydrocephalus.
El estoicismo-senequista de Don Enrique de Villena
Authors: Torres-Alcalá A. 
Published: January 2011

Le Stoïcisme sénéquiste de Don Enrique de Villena.
En 1423 Don Enrique de Villena écrivit une lettre consolatoire {carta consolatoria) à un ami, Juan Fernández de Valera, qui avait vu périr presque toute sa famille. Ce qu'il y a de curieux dans cette lettre, appelée aussi Traité de la Consolation {Tratado de la consolación), c'est qu'elle rompt avec la tradition médiévale qui considère la mort comme quelque chose d'horrible et de macabre. Dans le traité de Villena, il n'y a aucune référence à la preparatio mortis ni au contemptus mundi ni d'ailleurs aux considérations sur la décomposition physique qui faisaient les délices de l'homme médiéval. Le Moyen Age avait perdu sa sérénité devant la mort.
L'innovation de Villena est de ressusciter les consolatoires (las consolatorias) stoïciennes qui considèrent la mort avec la dignité et la sérénité humaines, et en une éthique naturaliste se fondent sur une eschatologie et une métaphysique panenthéiste de I'Être, de la Vertu et de la Nature. Villena est tout simplement notre premier homme de la Renaissance. En lisant son Traité de la Consolation nous avons une impression de « déjà vu », c'est-à-dire un écho de Sénèque, de son style et de sa doctrine, de sa sereine dignité, de son éthique et de sa métaphysique naturaliste.
El problema historio-gráfico de los Moriscos
Authors: Márquez Villanueva Francisco 
Published: January 2011

Le problème historio graphique des Morisques.
L'existence du peuple morisque et son expulsion de la Péninsule n'ont jamais cessé de poser un grave problème à la conscience nationale espagnole. La littérature apologétique officielle dans les années qui suivirent l'expulsion a présenté un cadre de références conceptuelles clairement reconnaissable chez les historiens et critiques du XIXe siècle. Une perspective antisémite et purement officielle a contribué à perpétuer (au-delà de considérations objectives pourtant évidentes) un système d'a-priori qui sacrifiait aux mythes de l'unanimité quant à la légitimité de l'expulsion, quant au morisque inassimilable et au mortel danger de conspiration. Les études les plus modernes ne parviennent pas à se libérer de cet héritage négatif, et cela, pour une grande part, à cause d'un problème heuristique créé par l'utilisation de sources documentaires où ne s'expriment que les points de vue les plus radicaux et les plus opposés : procès d'inquisition, polémiques sur l'exil. Il est ainsi impossible d'apprécier les choses avec modération et, surtout, de prendre en compte l'assimilation de certains secteurs du groupe morisque. La littérature (les chroniques de don Diego Hurtado de Mendoza et de Ginés Pérez de Hita, les supercheries de Miguel de Luna et particulièrement le phénomène complexe du récit littéraire de thème mauresque) nous permet de rectifier et de nuancer bien des choses. On y trouve des réalités, des jugements et des alternatives politiques très variés, parfois un désaccord avec les thèses officielles qui jusqu'ici étaient les seules utilisées. Ce n'est qu'en tenant compte de ces données que l'on peut échapper à l'emprise d'une mythification et ouvrir la voie à de nouvelles interprétations.
Ay cinquenta enxiemplos
Authors: Alvar Carlos 
Published: January 2011

Contrairement à ce que donnent à penser les témoignages qui se trouvent dans le texte et dans d'autres manuscrits, la présence du conte LI du Conde Lucanor dans un seul des manuscrits a suscité des discussions entre les critiques, sans qu'ils soient parvenus à un accord unanime.
L'auteur centre son étude sur la tradition didactique et moralisante : les œuvres les plus caractéristiques de ce genre ont, d'habitude, 50 ou 100 chapitres et, en général, cette structure ne varie pas. Tout laisse penser que Don Juan Manuel a suivi la tradition et que, par conséquent, le conte LI serait étranger au projet initial du Conde Lucanor.
La « Doncella a Dios » de Martín de Córdoba
Authors: Demerson P. 
Published: January 2011

« La Doncella a Dios » de Fray Martín de Córdoba.
Fray Martín de Córdoba, écrivain de l'école ascético-didactique, fut un des conseillers spirituels choisis par la reine veuve Isabelle de Portugal pour l'éducation de sa fille Isabelle, la future reine Catholique. Il composa son Jardin de Nobles Doncellas, manuel de perfection, où la jeune infante put apprendre à régler sa conduite et puiser d'édifiantes leçons.
Norma y creatividad en la rima idéntica (a propósito de Herrera)
Authors: Micó José María 
Published: January 2011

Tout élément formel en poésie, si minime qu'en soit l'importance, doit être étudié historiquement, en fonction des préceptes littéraires de son temps, de l'évolution des usages rhétoriques, des styles, de la langue poétique...
Ainsi en va-t-il pour la rime « du même au même ». Si la poétique traditionnelle condamne ce procédé, on peut voir qu'elle fait le plus grand cas de certains usages qui lui sont pourtant étroitement apparentés. Quelques grands créateurs ont eu de bonnes raisons de contrevenir aux règles. Dante, par exemple, entendit consacrer par les consonances de sa Commedia une idée biblique. En Espagne, quand les usages poétiques feront place au pétrarquisme, on observera chez nos poètes maint exemple de recherche formelle délibérée. De l'attrait exercé par ce procédé et de l'interdiction qui le frappe naît une tension qui apparaît dans les traductions en castillan de Pétrarque, de l'Arioste et d'autres poètes, traductions où la forme est moins marquée par la fidélité au discours original (même dans les versions « a lo divino ») que par les nouvelles tendances artistiques. Dans l'œuvre de Fernando de Herrera, lorsque celles-ci sont arrivées à maturité et qu'elles peuvent s'unir à une remarquable conscience créatrice, l'utilisation de la rime « du même au même » atteint à une perfection sans égale, mais seules des sources manuscrites nous offrent d'abondants témoignages de l'expressivité du procédé, de la variété et de la maîtrise avec lesquelles il est employé. Celui-ci, en revanche, est absent dans Algunas obras (1582) en raison notamment de la transgression qu'il représente encore, et ne se trouve guère dans le recueil posthume de Versos de 1619.
La difusión de libros e ideas en el Perú colonial. Análisis de bibliotecas particulares (siglo XVI)
Authors: Hampe Martinez T. 
Published: January 2011

Este artículo, basado en registros de embarque e inventarios de bibliotecas particulares, contribuye a la historia de las mentalidades del Perú colonial, señalando los libros, autores et ideas que más circularon en el virreinato durante el siglo XVI. Analiza una serie de catorce colecciones bibliográficas privadas, pertenecientes a diversos individuos : soldados de la hueste conquistadora, miembros del clero, funcionarios hacendísticos, magistrados de audiencias, un virrey, un inquisidor, un letrado hereje, un escribano rebelde. Los datos que suministran dichas fuentes sirven para diseñar un esquema de las obras más difundidas en el Perú, las cuales pueden ordenarse en las tres áreas temáticas de jurisprudencia, religión y humanidades ; sorprende constatar la supremacía que disfrutaron los textos jurídicos, orientados según la doctrina del Derecho común, que era considerada entonces un saber básico para todos quienes desempeñaban funciones políticas.
Una de las principales conclusiones del artículo es que los colonos indianos empleaban los libros fundamentalmente como un instrumento para mantenerse en contacto con los ambientes cultos de Europa. En efecto, la cultura libresca desarrollada en el Perú del siglo xvi muestra una directa sintonía con las corrientes ideológicas que por el mismo tiempo se divulgaban en el continente europeo. Cabe afirmar, por lo tanto, que pese a las ideas, hubo una profunda curiosidad intelectual y una notable apertura ideológica en el virreinato.