5,375 research outputs found
Totally intra-axial giant spinal schwannoma with late clinical onset
No full textA 44-year-old woman was hospitalized for a 2-month history of progressive spastic paraparesis and low back pain. A magnetic resonance imaging study showed a T7–L1 giant intradural extramedullary mass with total intra-axial development, causing vertebral bone scalloping with left dislocation of the spinal cord (FigureA–B). At surgery, after exposure of the T6–L3 segments, laminar bone erosion was evident. A T7–L2 laminectomy and dura mater opening were then performed, identifying the upper and lower poles of the tumor. The mass was gently dissected from spinal cord and cauda equina roots and then removed en bloc (Figure C). Histopathological examination documented a schwannoma. The postoperative course was uneventful. By 6-months postsurgery, the patient was able to walk without support and returned to her previous occupation. A postoperative magnetic resonance imaging scan documented complete removal of the lesion (Figure D). Only one other case of a giant spinal schwannoma (defined as a schwannoma extending greater than two vertebral levels [1]) with minimal neurological deficit has been reported [2]
Internal cerebral veins varix due to midline arteriovenous malformation: how much is the risk of bleeding?
No full textSpringer-Verlag 2011
Sir,
We report a case of 40-year-old sportsman admitted to our
department for a generalized seizure associated with
bladder and bowel incontinence occurred during exercise.
The patient quickly regained consciousness without postcritical
deficits. Neurological examination appeared completely
normal. A head computer tomography (CT) scan
showed a midline arteriovenous malformation (AVM)
without the evidence of bleeding (Fig. 1a, b). A digital
subtraction angiography revealed a dysplastic nidus fed by
branches of bilateral internal–external carotid and vertebrobasilar
arteries, and draining both in the superficial and
deep venous system, which showed varicose dilatation with
Galen’s vein stenosis (Fig. 1c–g).
Cerebral varix is defined as an ectasia which doubles
vein diameter. It can be due to an arteriovenous shunt and
appears more common in patients with direct fistulas, than
in cerebral AVM with dysplastic nidi [1]. Differently from
those associated with Galen’s vein fistulae, huge intracranial
varix associated with cerebral AVMs were seldom
reported. Headache, bruit, focal mass effect and hydrocephalus
are common presentation symptoms [2]. Intracranial
haemorrhage has been instead less often reported at
clinical onset [3]. In the most of the cases of giant varix,
direct arteriovenous communications in the context of
nidus were observed, especially between feeding arteries
and the varicose veins [4]. This discrete angiographic
finding separate these vascular malformations from the
classical and more common AVMs in which an abnormal
vascular network is identified between the arterial feeders
and draining veins [4]. Venous hypertension with retrograde
drainage often results in focal neurological deficits
and seizures [1]. Although it is commonly assumed that
venous ectasia increases the bleeding risk, varix haemorrhagic
presentation has been rarely reported [4]. It is may
be due to the progressive thickening of the arterialized
veins wall, with intimal proliferation of synthetic smoothmuscle
cells and disappearance of the internal elastic
lamina, that make arterialized veins not greatly prone to
rupture [1, 4].
On the other hand, instead, the presence of venous varix
on the draining veins has been recognized as a factor
increasing the risk of haemorrhage in dural arteriovenous
fistulae [5].
In the case reported here, the presence of multiple
feeders causing high flow shunt rate, direct drainage in a
cisternal venous system, and an impaired venous outlet due
to the Galen’s vein stenosis, may have contributed to the
varix formation. Prolonged sporting activity, instead, has
not been a factor influencing AVM rupture
Flow diversion for indirect carotid-cavernous fistula: Still an off-label indication?
No full textBackground: Flow diversion (FD) is an established treatment for large or giant wide-necked unruptured intracranial aneurysms. In the past few years, the use of flow diverter devices was extended to several other “off-label” indications, including solitary or adjunctive treatment to coil embolization for direct (Barrow A type) carotid cavernous fistulas (CCFs). The use of liquid embolic agents still represents the first-line treatment for indirect CCFs. Typically, the ipsilateral inferior petrosal sinus or superior ophthalmic vein (SOV) is the preferred transvenous routes to access CCFs. In some cases, vessel tortuosity or different features make the endovascular access challenging, thus requiring different approaches and strategies. The aim of the study is to discuss rational and technical aspect in treating indirect CCFs referring to the most up-to-date literature. An alternative experience-based endovascular strategy with FD is described. Methods: We report the case of a 54-year-old woman diagnosed with indirect CCF and treated with flow diverter stent. Results: After multiple unsuccessful attempts at transarterial right SOV catheterization, a right indirect CCF fed by a single trunk at the ophthalmic origin from the internal carotid artery (ICA) was treated by ICA standalone FD. Blood flow was redirect and successfully reduced through the fistula, with immediately postprocedure improvement of the patient’s clinical status (ipsilateral proptosis and chemosis). Ten-months radiological followup showed the complete obliteration of the fistula. No adjunctive endovascular treatment was performed. Conclusion: FD appears a reasonable alternative stand-alone endovascular strategy also for selected difficult-to-access indirect CCFs, when all conventional routes are judged unfeasible. Further investigations will be necessary to better define and support this potential lesson-learned application
Stem Cell Strategies in Promoting Neuronal Regeneration after Spinal Cord Injury: A Systematic Review
Get PDFSpinal cord injury (SCI) is a devastating condition with a significant medical and socioeconomic impact. To date, no effective treatment is available that can enable neuronal regeneration and recovery of function at the damaged level. This is thought to be due to scar formation, axonal degeneration and a strong inflammatory response inducing a loss of neurons followed by a cascade of events that leads to further spinal cord damage. Many experimental studies demonstrate the therapeutic effect of stem cells in SCI due to their ability to differentiate into neuronal cells and release neurotrophic factors. Therefore, it appears to be a valid strategy to use in the field of regenerative medicine. This review aims to provide an up-to-date summary of the current research status, challenges, and future directions for stem cell therapy in SCI models, providing an overview of this constantly evolving and promising field
Retrospective application of risk scores to ruptured intracranial aneurysms: would they have predicted the risk of bleeding?
No full textAs the incidental diagnosis of unruptured intracranial aneurysms has been increasing, several scores were developed to predict risk of rupture and growth to guide the management choice. We retrospectively applied these scores to a multicenter series of patients with subarachnoid hemorrhage to test whether they would have predicted the risk of bleeding in the event of aneurysm discovery previous to its rupture. Demographical, clinical, and radiological information of 245 adults were retrieved from two neurovascular centers' database. Data were pooled and PHASES, UCAS, and ELAPSS scores were retrospectively calculated for the whole population and their performances in identifying aneurysms at risk of rupture were compared. Mean PHASES, UCAS, and ELAPSS scores were 5.12 +/- 3.08, 5.09 +/- 2.62, and 15.88 +/- 8.07, respectively. Around half (46%) of patients would have been assigned to the low- or very low-risk class (5-year rupture risk < 1%) in PHASES. Around 28% of patients would have been in a low-risk class, with a probability of 3-year rupture risk < 1% according to UCAS. Finally, ELAPSS score application showed a wider distribution among the risk classes, but a significant proportion of patients (45.5%) lie in the low- or intermediate-risk class for aneurysm growth. A high percentage of patients with ruptured aneurysms in this multicenter cohort would have been assigned to the lower risk categories for aneurysm growth and rupture with all the tested scores if they had been discovered before the rupture. Based on these observations, physicians should be careful about drawing therapeutic conclusions solely based on application of these scores
Single nucleotide polymorphisms associated with sporadic brain arteriovenous malformations: where do we stand?
No full textBrain arteriovenous malformations are characterized by a tangle of abnormal vessels directly shunting blood from the arterial to venous circulation. They are known to occur either sporadically or in the context of well-defined genetic disorders. Haemorrhage represents the most severe clinical manifestation, whereas other common symptoms include headache, seizures and neurological deficits. Although sporadic forms do not recognize a specific genetic cause, in recent years, it has been hypothesized that genes involved in angiogenesis and inflammation or coding for proteins, such as fibronectins, laminins and integrins, may play a role in the pathophysiology of brain arteriovenous malformations. More recently, a new trend of genetic studies has investigated the association between sporadic arteriovenous malformations and single nucleotide polymorphisms, single base variations between genomes within members of a biological species or between paired chromosomes in an individual, which may determine the
susceptibility to develop complex diseases and influence their natural history. Several polymorphisms in two different families of genes have been associated with disease susceptibly and increased haemorrhagic risk. These genes are mainly involved in the
inflammatory cascade and in the regulation of angiogenesis. However, most of the investigated polymorphisms have been selected on the basis of candidate genes because of their potential functional role in the pathogenesis of brain arteriovenous
malformations or in other cerebrovascular diseases. Only one hypothesis-free genome-wide association study in a small number of patients has been performed so far, but it was unable to identify significant associations between brain arteriovenous
malformations and specific genetic loci. In this article, we review and analyse the polymorphisms investigated to date in association with sporadic brain arteriovenous malformations in the medical literature. We discuss the biological, pathophysiological and clinical implications of these studies, with particular attention to the prediction of haemorrhagic risk and the
possibility of building genetic profiles capable of defining the architectural features of the malformations and predict their
evolution and natural history. We also present a joint analysis of the risk estimates found by the studies in literature that have evaluated the association between single nucleotide polymorphisms and brain arteriovenous malformation susceptibility and risk
of bleeding. This analysis shows a statistically significant association between the interleukin 6 174G4C (odds ratio = 1.97; 95% confidence interval: 1.15–3.38) and the tumour necrosis factor a 238G4A (odds ratio = 2.19; 95% confidence interval: 1.25–3.83) gene polymorphisms and risk of intracranial haemorrhage and between the activin-like kinase 1 (also known as ACVRL1) intervening sequence 3 -35A4G (odds ratio = 2.42; 95% confidence interval: 1.54–3.8) gene polymorphism and disease susceptibility
Association between the rs1333040 polymorphism on the chromosomal 9p21 locus and sporadic brain arteriovenous malformations
No full textBackground. Single nucleotide polymorphisms (SNPs) on chromosome 9p21 have been recently associated with intracranial aneurysms and stroke. In this study, we tested the association between the rs1333040C>T polymorphism on the 9p21 locus and sporadic brain
arteriovenous malformations (BAVMs).
Methods We studied 78 patients with sporadic BAVMs and 103 unaffected controls. Genomic DNA was isolated
from peripheral blood and the rs1333040C>T polymorphism was assessed by PCR–restriction fragment length polymorphism using the BsmI restriction
endonuclease. Results. We found that the distribution of the three genotypes (TT/TC/CC) of the rs1333040 polymorphism
was significantly different between cases and controls (p=0.02). Using dominant, recessive and additive genetic models, we found that the TT genotype and the T allele were significantly more common in the BAVM
group than in controls. We also evaluated whether the rs1333040 polymorphism was associated with prototypical angio-architectural features of BAVMs (such as nidus size, venous drainage pattern and Spetzler–
Martin grading) and with the occurrence of seizures and bleeding. We detected a significant association between the homozygous T allele in the recessive model and BAVMs with a nidus >4 cm in diameter. Deep venous drainage was significantly more frequent among subjects carrying at least one T allele in the dominant model. Patients with seizures showed a significant association
with the TT genotype and the T allele in all genetic models examined whereas those who experienced intracranial bleeding showed a significant association
with the T allele in the trend model.
Conclusions. This is the first study demonstrating an association between an SNP of the 9p21 region and sporadic BAVMs. Our results emphasise the relevance of this chromosomal locus as a common risk factor for various forms of cerebrovascular diseases
Open access self-archiving: An author study
No full textThis, our second author international, cross-disciplinary study on open access had 1296 respondents. Its focus was on self-archiving. Almost half (49%) of the respondent population have self-archived at least one article during the last three years. Use of institutional repositories for this purpose has doubled and usage has increased by almost 60% for subject-based repositories. Self-archiving activity is greatest amongst those who publish the largest number of papers. There is still a substantial proportion of authors unaware of the possibility of providing open access to their work by self-archiving. Of the authors who have not yet self-archived any articles, 71% remain unaware of the option. With 49% of the author population having self-archived in some way, this means that 36% of the total author population (71% of the remaining 51%), has not yet been appraised of this way of providing open access. Authors have frequently expressed reluctance to self-archive because of the perceived time required and possible technical difficulties in carrying out this activity, yet findings here show that only 20% of authors found some degree of difficulty with the first act of depositing an article in a repository, and that this dropped to 9% for subsequent deposits. Another author worry is about infringing agreed copyright agreements with publishers, yet only 10% of authors currently know of the SHERPA/RoMEO list of publisher permissions policies with respect to self-archiving, where clear guidance as to what a publisher permits is provided. Where it is not known if permission is required, however, authors are not seeking it and are self-archiving without it. Communicating their results to peers remains the primary reason for scholars publishing their work; in other words,
researchers publish to have an impact on their field. The vast majority of authors (81%) would willingly comply with a mandate from their employer or research funder to deposit copies of their articles in an institutional or subject-based repository. A further 13% would comply reluctantly; 5% would not comply with such a mandate
- …
