1,721,011 research outputs found
Venous preservation–guided resection: a changing paradigm in parasagittal meningioma surgery
No full textObject. Surgical treatment of parasagittal meningiomas is challenging. Preserving the venous outflow is the key point, but this may preclude radical resection. Different surgical strategies have been proposed. To contribute to the debate on the optimal strategy for treating these tumors, a single-institutional, single-surgeon series of patients with parasagittal meningiomas was analyzed and the available literature reviewed.
Methods. Clinical charts of patients with parasagittal meningioma, managed at the University of Messina be- tween 1988 and 2008, were retrospectively reviewed. A microsurgical resection, the goal of which was to preserve the venous outflow, was performed. Only if the superior sagittal sinus (SSS) was angiographically occluded, but if alternative venous outflow was clearly recognized, was the tumor resected, together with the sinus without further flow restoration. A MEDLINE review of the literature published between 1955 and 2011 was performed.
Results. Long-term follow-up (mean 80 months) data obtained in 67 patients with meningiomas involving the SSS were analyzed. The recurrence rate was 10.4%; the morbidity and mortality rates were 10.4% and 4.5%, re- spectively. The authors identified in the literature 19 relevant studies on this issue, and based on their review of the literature, there is no evidence that aggressive management offers an advantage in terms of recurrence rate.
Conclusions. Analysis of the data obtained in the 67 patients confirmed good outcome and long-term tumor control following a surgical strategy aimed to preserve venous outflow. These findings and the results of the authors’ analysis of the literature emphasize that the goal of radical tumor resection should be balanced by an awareness of the increased surgical risk attendant on aggressive management of the SSS and bridging veins
Telemedicine-assisted treatment of patients with intracerebral hemorrhage
No full textObject. Telemedicine provides a new approach to improve stroke care in community settings, delivering acute
stroke expertise to hospitals in rural areas. Given the controversies in many aspects of the treatment of intracerebral
hemorrhage (ICH) and the lack of guidelines, a prompt neurosurgical second opinion may facilitate the treatment of
patients with ICH. Here, the authors’ 8-year experience with the use of telemedicine in the management of ICH is
reported.
Methods. The medical records of patients with ICH treated through a telemedicine system in the district of
Messina, Italy, between June 2003 and June 2011 were retrospectively reviewed. Neuroradiological and clinical
data for patients were transmitted through a high-technology “hub-and-spoke” telemedicine network. Neurosurgical
teleconsulting (at the hub) was available for 7 peripheral hospitals (spokes) serving about 700,000 people. The authors analyzed 1) the time between peripheral hospital admission and the specialized second opinion consultation, 2)
primary and secondary transfers to the authors’ neurosurgery department, and 3) the treatments (surgical or medical)
of patients transferred to the hub.
Results. The telemedicine network was used to treat more than 2800 patients, 733 with ICH. A neurosurgical
consultation was provided in 38 minutes versus 160 minutes for a consultation without telemedicine. One hundred
seventy-six (24%) of 733 patients were primarily transferred to the hub. Ninety-five patients (13%) underwent surgical treatment. The remaining 81 patients (11%) underwent neurointensive care. Eight (1.4%) of 557 patients treated
at the spokes needed a secondary transfer for surgical treatment because of a worsening clinical condition and/or CT
findings. Considering secondary and inappropriate transfers, the interpretation of data was correct in 96.5% of cases.
Conclusions. Telemedicine allowed rapid visualization of neuroradiological and clinical data, providing neurosurgical expertise to community hospitals on demand and within minutes. It allowed the treatment of patients at
peripheral hospitals and optimized resources. A small percentage of patients treated at the peripheral hospitals had
secondary deterioration. Telemedicine allowed fast patient transfer when necessary and provided improved accuracy
in patient car
Nitric oxide in the injured spinal cord: Synthases cross-talk, oxidative stress and inflammation
No full textNitric oxide (NO) is a unique informational molecule involved in a variety of physiological
processes in the central nervous system (CNS). It has been demonstrated that it can exert
both protective and detrimental effects in several disease states of the CNS, including spinal
cord injury (SCI).
The effects of NO on the spinal cord depend on several factors such as: concentration of
produced NO, activity of different synthase isoforms, cellular source of production and time
of release. Basically, it has been shown that low NO concentrations may play a role in
physiologic processes, whereas large amounts of NO may be detrimental by increasing
oxidative stress. However, this does not explain all the discrepancies evidenced studying the
effects of NO in SCI models. The analysis of the different synthase isoforms, of their
temporal profile of activation and cellular source has shed light on this topic. Two postinjury
time intervals can be defined with reference to the NO production: immediately after
injury and several hours-to-days later. The initial immediate peak of NO production after
injury is due to the up-regulation of the neuronal NO synthase (nNOS) in resident spinal cord
cells. The late peak is due primarily to the activity of inducible NOS (iNOS) produced by
inflammatory infiltrating cells. High NO levels produced by up-regulated nNOS and iNOS are
neurotoxic; the down-regulation of nNOS corresponds temporally to the expression of iNOS.
On the bases of those evidence, therapeutic approaches should be aimed: (1) to reduce the
NO-elicited damage by inhibition of specific synthases according to the temporal profile of
activation; (2) by maintaining physiologic amount of NO to keep the induction of iNO
Intraoperative microvascular Doppler monitoring of blood flow within a spinal dural arteriovenous fistula: a precious surgical tool. Case report.
Full text linkThe authors describe a case of spinal arteriovenous fistula (AVF) treated by a microvascular Doppler-assisted surgical interruption of the arterialized vein. Microvascular Doppler monitoring represents a valid, widely available, noninvasive tool that enables identification, through flow spectrum analysis, of components of this type of vascular malformation. In this case because the location of the fistula was identified prior to opening the dura only minimally invasive surgery was required. Direct recordings of the arterialized draining vein and the nidus of the fistula demonstrated a pathological spectrum caused by the arterial supply and the disturbed venous outflow in which a high-resistance flow pattern and low diastolic flow resembling an arterial-like flow velocity were observed. The fistula was obliterated by interruption of the draining vein, and Doppler measurements provided information on flow velocity changes in the medullary veins from an arterial to a venous pattern. The absence of any residual flow in the AVF confirmed successful hemodynamic treatment. Intraoperative microvascular Doppler recording during surgical closure of spinal AVF is a widely available and reliable monitoring modality that helps to produce excellent clinical results
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
Role of inflammation in the secondary injury following experimental spinal cord trauma
No full textThe primary traumatic mechanical injury to the spinal cord causes the death of a number of neurons that cannot be recovered, neither regenerated. However, neurons continue to die for hours after spinal cord injury (SCI), and this represents a potentially avoidable event. One of mechanisms that have been touted to contribute importantly to the evolution of such secondary cell death is the local inflammatory response in the injured spinal cord. In this report we have used an in vivo model to induce acute SCI and reproduce the acute pathological events associated with inflammation after traumatic SCI in rats
Endoscopic transoral-transclival approach to the brainstem and surrounding cisternal space: Anatomic study
No full textOBJECTIVE: The purpose of this study was to review the endoscopic anatomic features of the anterior brainstem and surrounding cisternal spaces via a transoral-transclival approach.
METHODS: Fifteen adult human cadaveric heads, obtained from 10 fresh cadavers and 5 formalin-fixed cadavers, were used to demonstrate both the feasibility of an endoscopic transoral-transclival intradural approach and its exposure potential. To analyze the exact extension of a safe entry zone through the clivus, 20 skull bases were used to obtain anatomic measurements.
RESULTS: The transoral approach was performed without maxillotomy or mandibu- lotomy and with a clival opening of 20 by 15 mm. Such a limited clival and dural opening allowed the insertion of the endoscope and instruments, full visualization of the anterolateral brainstem and cisternal spaces around it, and reconstruction of all anatomic layers by means of a paraendoscopic technique.
CONCLUSION: The endoscopic transoral-transclival approach enables full access to the anterolateral brainstem and to the cisternal space around it. The use of the endoscope has the potential to reduce the need for a wider cranial base opening and the danger of postoperative complications
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
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