1,720,976 research outputs found
Extraforaminale lumbale discushernia
No full textDe anatomische opbouw van de wervelzuil maakt dat de spinale zenuwwortel die doorheen de paramediane ruimte loopt, verschilt van deze die door de extraforaminale ruimte loopt. Een extraforaminale discushernia geeft aldus compressie van een andere zenuwwortel dan een klassieke hernia op hetzelfde niveau. De prevalentie bedraagt ongeveer 1,78-6,1% van alle lumbale discushernia’s. Het voornaamste symptoom is radiculaire pijn. Daarnaast zijn lage rugpijn en sensomotorische uitvalsverschijnselen eveneens veelvoorkomend. Klinisch onderzoek omvat de „straight leg raising-test” (SLR), de omgekeerde SLR-test, de evaluatie van de reflexen, sensorimotorische uitval en radiculaire uitstralende pijn. In vergelijking met de klassieke discushernia blijkt de pijnbeleving meer uitgesproken te zijn. De MRI is de gouden standaard binnen de medische beeldvorming. De eerstelijnsbehandeling is conservatief (niet-steroïdale anti-inflammatoire geneesmiddelen (NSAID’s), steroïden, bedrust, …). Bij falen van deze therapie of bij duidelijke sensorimotorische uitval kan men opteren voor heelkunde. Epidurale corticoïdinjectie kan de pijn significant verlichten. De literatuurstudie en het patiëntendossieronderzoek tonen een gelijke leeftijdsverdeling. In beide studies bedroeg de prevalentie van radiculaire pijn 100%. Er werd minder vaak rugpijn opgetekend in het dossieronderzoek. De succesratio van het operatief ingrijpen (68% tot 79%) in de studie benadert de cijfers uit de literatuur. De chirurgische uitkomst is niet gerelateerd aan het niveau van de hernia.Dit werk is tot stand gekomen dankzij prof. dr.
Frank Weyns, dr. Thomas Daenekindt en dr. Eveleen Buelens. We danken prof. dr. Weyns hierbij
voor het aanbieden van dit boeiende onderwerp,
het toereiken van informatie en het kritisch evalueren van de tekst. Eveneens willen we de afdeling
neurochirurgie van het ZOL campus St. Jan danken
voor hun hulp bij het uitwerken van het patiëntenonderzoek
5-Aminolevulinic acid for recurrent malignant gliomas: A systematic review
No full textOBJECTIVES: Nowadays, several techniques have been developed in order to guide neurosurgeons during intended maximal safe resection of high-grade gliomas (HGG). Fluorescence-guided microsurgery using 5-aminolevulinic acid (5-ALA) is one of these. A large amount of studies have been performed evaluating benefits in newly diagnosed HGG. However, little is known about the safety, accuracy and efficacy in recurrent HGG. The primary objective of this thesis is to examine the value of 5-ALA in patients with recurrent HGG concerning diagnostic accuracy, extent of resection (EOR), safety and survival compared to white-light resection. As a secondary objective, we compared these results with current literature concerning 5-ALA in newly diagnosed HGG. PATIENTS AND METHODS: We performed a systematic review and included eighteen articles obtained from MEDLINE, EMBASE, Web of Science and TRIP database. Search terms include "glioma" and "aminolevulinic acid". Additional studies were identified through checking the reference lists. This study is in conformity with the PRISMA and BMJ guidelines. RESULTS: 5-ALA shows similar results regarding diagnostic accuracy in recurrent HGG compared to newly diagnosed HGG, although specificity and negative predictive value seem lower. It shows complementary value in identifying tumor boundaries compared to MRI-neuronavigation. Diagnostic accuracy is not influenced by previous chemo- or radiotherapy. New neurological deficits proved to be similar and were in general mainly temporary. However, adverse events overall were more common. Therefore, indications for repeat surgery should be followed strictly. 5-ALA might increase overall survival in recurrent gliomas, but has no clear impact on progression-free survival. CONCLUSION: 5-ALA should be regarded as a useful and safe intraoperative tool in recurrent glioma surgery.status: Publishe
Neuritis ossificans mimicking a malignancy in a child: case report and literature review
No full textWe present the case of a child with neuritis ossificans after acute trauma, treated conservatively. The aim of the review is to compare several parameters in this disease. Emphasis is placed on the clinical-radiological features distinguishing neuritis ossificans from malignancy to avoid unnecessary biopsy and surgery.A literature review was performed. Only 18 cases were described. Except for one, all describe adults, and none had acute trauma. Nearly all were treated surgically.Our 13-year-old patient presented with posterior knee pain after trauma. MRI demonstrated a mass within the tibial nerve with oedema, some lymph nodes and increased avidity on 18fluoro-2-deoxyglucose-positron emission tomography. These findings can be reactive but also associated with malignancy. However, eggshell-like calcifications in the periphery of the mass were seen on CT. Biopsy and resection were proposed. Follow-up visits over the next weeks showed remarkable clinical improvement. Wait-and-scan was advised after international discussion. Follow-up imaging after 2 months showed resolution of the oedema and volume reduction of the mass, suggesting a benign pathology. Diagnosis of neuritis ossificans was proposed based on the clinical and radiological features. There was a favorable course with no complaints after two months. Imaging after seven months showed an almost complete regression.Neuritis ossificans should be considered within a painfull (mono)neuropathy. The initial inflammatory phase may mimic malignancy, misleading clinicians toward biopsy or surgery with the risk of nerve damage. As seen in our case, neuritis ossificans can be a self-limiting process. Therefore, conservative therapy should be considered with a wait-and-scan approach
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
FUNCTIONAL MAGNETIC RESONANCE IMAGING FOR PREOPERATIVE LOCALISATION OF ELOQUENT BRAIN AREAS RELATIVE TO BRAIN TUMOURS: CLINICAL IMPLEMENTATION IN A REGIONAL HOSPITAL
No full textThe purpose of this study was to evaluate the implementation of functional magnetic resonance imaging (fMRI) for clinical use in patients with a brain tumour in the setting of a regional hospital. Twenty-three patients underwent a fMRI examination as preoperative evaluation for a tumour adjacent to a eloquent brain area. The location and distance of the tumour relative to the fMRI activation area for this eloquent brain area was determined. Presence of postoperative neurological deficits was compared to the result of the fMRI examination. The fMRI examination was not interpretable in four of the twenty-three patients. In nine patients the eloquent brain area was located more than two centimetres from the tumour: seven showed no neurological deficit postoperatively, one patient experienced a temporary deficit, and one patient has not been operated yet. In the remaining ten patients the eloquent brain area was located less than two centimetres from the tumour: after (partial) resection of the tumour often using intra-operative cortical stimulation, six patients showed no neurological deficits, and three patients had temporary or permanent deficits. One patient was not operated. The clinical implementation of fMRI was successful in the preoperative evaluation of patients with a brain tumour and useful to plan the surgical intervention and to minimize postoperative neurological deficits
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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