Trans-sulcal versus trans-parenchymal approach in supratentorial cavernomas. A multicentric experience.

OBJECTIVES: Cavernous malformations (CM) are low-flow vascular lesions that can cause significant symptoms and neurological deficits. Different intraoperative surgical approaches have been developed. Aim of the present investigation is the comparison between the trans-sulcal approach (TS) and the trans-parenchymal neuronavigation-assisted approach (TPN) in a surgical series from two neurosurgical centers. The technique and clinical outcomes are discussed, with a specific focus on seizure outcome. PATIENTS AND METHODS: Clinical and radiological data from two neurosurgical centers ("A. Gemelli" Hospital in Rome and A.O.U. Città della Salute e della Scienza in Turin) were retrospectively reviewed in order to evaluate the different outcome of TS and TPN approach for cavernous malformation treatment. RESULTS: A total of 177 patients underwent surgical intervention for supratentorial CM, 130 patients with TPN approach and 47 with TS approach. TS approach was associated with higher rate of seizure in early post-operative period both in epileptic patients (p < 0,001) and in patients without history of seizures before surgery (p = 0,002). Moreover, length of incision (p < 0,001), area of craniotomy (p < 0,001) and corticectomy (p < 0,001) were bigger in TS than in TPN approach. Brain contusion (p < 0,001) and fluid collection (p < 0,001) were more likely to be discovered after TS approach. CONCLUSIONS: TPN is a valuable approach for resection of CM. Minor complications are significantly lower in TPN approach when compared with TS approach. In addition, it is associated with lower rate of early post-operative seizure and shorter length of stay.

Assessing Restoration Effects on River Hydromorphology Using the Process-based Morphological Quality Index in Eight European River Reaches.

The Morphological Quality Index (MQI) and the Morphological Quality Index for monitoring (MQIm) have been applied to eight case studies across Europe with the objective of analyzing the hydromorphological response to various restoration measures and of comparing the results of the MQI and MQIm as a morphological assessment applied at the reach scale, with a conventional site scale physical-habitat assessment method. For each restored reach, the two indices were applied to the pre-restoration and post-restoration conditions. The restored reach was also compared to an adjacent, degraded reach. Results show that in all cases the restoration measures improved the morphological quality of the reach, but that the degree of improvement depends on many factors, including the initial morphological conditions, the length of the restored portion in relation to the reach length, and on the type of intervention. The comparison with a conventional site scale physical-habitat assessment method shows that the MQI and MQIm are best suited for the evaluation of restoration effects on river hydromorphology at the geomorphologically-relevant scale of the river reach.

New tools for the hydromorphological assessment and monitoring of European streams.

Hydromorphological stream assessment has significantly expanded over the last years, but a need has emerged from recent reviews for more comprehensive, process-based methods that consider the character and dynamics of the river with greater accuracy. With this as a focus, a series of hydromorphological tools have been developed and/or further extended in Europe within the context of the REFORM (REstoring rivers FOR effective catchment Management) project. The aim of this paper is to present the set of REFORM hydromorphological assessment methods and, based on some examples of their application, to illustrate and discuss their synergic use, specific features, limitations and strengths. This assessment and monitoring includes three tools: the Morphological Quality Index (MQI), the Morphological Quality Index for monitoring (MQIm), and the Geomorphic Units survey and classification System (GUS). These tools constitute the assessment phase of an overall multi-scale, process-based hydromorphological framework developed in REFORM. The MQI is aimed at an assessment, classification and monitoring of the current morphological state; the MQIm aims at monitoring the tendency of morphological conditions (enhancement or deterioration); the GUS provides a characterization, classification and monitoring of geomorphic units. A series of examples are used to illustrate the potential range of application, including: (i) an assessment of morphological conditions; (ii) an assessment of the morphological effects of restoration projects; (iii) an evaluation of the geomorphic impacts of interventions for risk mitigation; and (iv) an integrated use of MQI and GUS to assess and characterise morphological conditions. Finally, some of the main features, strengths and peculiarities of the three hydromorphological tools are discussed with the support of examples of their application.

Diagnosis and management of dural arteriovenous fistulas: a 10 years single-center experience.

OBJECTIVES: Dural arteriovenous fistulas (DAVFs) are a challenging condition in vascular neurosurgery. Disease natural history and its management is still debated. In the present paper we report our center series on DAVFs over a period of 10 years. Our data were compared with relevant literature. PATIENT AND METHODS: Our series includes 45 cases: 14 cavernous sinus, 11 transverse-sigmoid, 8 patients tentorial, 6 anterior cranial fossa, 5 patients spinal, 1 patient foramen magnum. RESULTS AND CONCLUSIONS: DVAFs distribution, clinical presentation and hemorrhagic risk are discussed. Cavernous sinus DAVFs are the most common site in our series. Other locations in order of frequency are transverse-sigmoid sinus, tentorial, anterior cranial fossa, spinal and foramen magnum. The majority of patients presented with non-aggressive symptoms. 18% presented with intracranial hemorrhage: all the hemorrhages occurred in high-grade DAVFs. For most patients, endovascular treatment, transarterial or transvenous, was the first option. Surgery was performed for the anterior cranial fossa DAVFs and other complex lesions draining mostly transverse-sigmoid sinus and tentorium. In 7% of cases a combination of endovascular+surgical treatment was used. Our series has been carefully analyzed in comparison 'side by side' with most relevant literature on DVAFs, focusing particularly on management strategies, therapeutic options and risks related to treatment.

Indocyanine green video-angiography in neurosurgery: a glance beyond vascular applications.

OBJECTIVE: Indocyanine green video angiography (ICG-VA) is a non invasive, easy to use and a very useful tool for various neurosurgical procedures. Initially introduced in vascular neurosurgery since 2003, it's applications have broadened over time, both in vascular applications and in other neurosurgical fields. The objective of our study is to review all published literature about ICG-VA, cataloguing its different applications. METHODS: A systematic review of all pertinent literature articles published from January 2003 to May 2014 using Pubmed access was performed using pertinent keywords; cross check of references of selected articles was performed in order to complete bibliographical research. Results of research were grouped by pathology. RESULTS AND CONCLUSIONS: The paper systematically analyses ICG-VA different applications in neurosurgery, from vascular neurosurgery to tumor resection and endoscopic applications, focusing on reported advantages and disadvantages, and discussing future perspectives.

Protective effect of external ventricular drainage on cerebral vasospasm. A retrospective study on aneurysmal SAH treated endovascularly.

OBJECTIVE: Cerebral vasospasm (VS) is one of the factors that can most significantly worsen the prognosis after aneurysmal subarachnoid hemorrhage (SAH). A substantial body of evidence supports the idea that CSF diversion could prevent VS, even if this issue is still much debated. External ventricular drainage (EVD) is the recommended procedure for post-hemorrhagic hydrocephalus. In this study we analyzed whether EVD, placed for acute hydrocephalus, is effective in reducing the incidence of clinical and radiological cerebral vasospasm in patients who underwent endovascular treatment for aneurysmal SAH. PATIENTS AND METHODS: We retrospectively studied the incidence of radiologically confirmed VS in 141 patients treated endovascularly for aneurysmal SAH: 80 underwent EVD for hydrocephalus, 61 did not undergo EVD. RESULTS: VS occurred in 8.75% of cases (7 patients) in the first groups, while in 22.95% (14 patients) in the second group. In addition, patients not treated with EVD display a prevalence of VS in lower Fisher grades compared to the other group. CONCLUSION: Our data indicate that CSF drainage reduces the risk of vasospasms in patients with endovascular treatment for aneurysmal SAH.

Anatomical variants of the basal vein of Rosenthal: prevalence in idiopathic subarachnoid hemorrhage.

BACKGROUND: Spontaneous, non traumatic subarachnoid hemorrhage (SAH) is a significant clinical problem that occurs most commonly as a result of aneurysm rupture. In approximately 15 % of cases, nor aneurysm or other vascular malformation can be identified by cerebral angiography as origin of the hemorrhage, and these are commonly defined as idiopathic SAH (ISAH). Because of the negative angiography, limited extension of the bleeding with prevalent prepontine pattern and the benign prognosis, the venous causes has been preferred rather than the arterial ones. In the literature recent studies have suggested a possible contribution by primitive variants of Basal vein of Rosenthal (BVR) in its the pathogenesis of ISAH, commonly grouped according Watanabe classification (type A, B and C). In this paper we evaluated the prevalence of anatomical variants of BVR in ISAH. METHODS: Venous drainage at angiography was retrospectively analyzed in 40 patients with ISAH and in 40 with unruptured aneurysms as controls. RESULTS AND CONCLUSIONS: Previous studies displayed a significant prevalence of BVR type C variants in ISAH. Conversely in our study we recognized variant B as prevalent, in which the BVR bifurcates to drain anteriorly into the uncal vein and posteriorly into the Galenic system. Similarly to variant C (in which the BVR drains via perimesencephalic "bridging" veins into cavernous, sphenoparietal, petrosal sinus or directly into transverse sinus) also variant B might be subjected to those stress mechanisms and intrinsic system 'fragility' and for reasons yet to determine, sets off a consequent hemorrhage with clinical and radiological features typical of ISAH.

Transcriptional profile characterization for the identification of peripheral blood biomarkers in patients with cerebral aneurysms.

We tried to identify molecular markers in peripheral blood to predict high risk of aneurysm rupture. Extraction of the total population of peripheral blood mononuclear cell (PBMC) from total blood volume, total RNA extraction from PBMC and Agilent One Color Gene-expression Oligo-Microarray were performed on peripheral venous blood samples from 45 patients with ruptured, unruptured cerebral aneurysms and control group (15). Mean foreground/ background signal intensities and A (log2(R*G)/2) values were calculated for each spot. Genes with absolute fold change (FC) greater than or equal to plus or minus 1.5 and p-value less than 0.05 were considered differentially expressed in the 3 groups (Student T-test). Genes coding for MMPs were strongly underexpressed in ruptured aneurysms group, suggesting a possible role in aneurysms development more than their rupture. Genes coding for adhesine proteins of the extracellular matrix (ICAM1) and cytoskeleton (WIPF1,TUBA4A) were underexpressed in ruptured aneurysms. Genes coding proteins involved in the regulation of apoptotic processes may be important in aneurysm development and rupture, resulting into an increased rate of remodeling processes in the arterial wall. Fas coding gene, SUMO1, ZFAT, BCL2, CCR5 genes were all over-represented in unruptured aneurysms. The coexisting over-representation of pro-apoptotic genes and the underexpression of cytoskeleton and extracellular matrix genes confirms that aneurysms development and evolution are part of a degenerative process of the arterial wall not involved in aneurysms rupture. MMPs may be involved in repairing chronic damages to the arterial walls and preventing SAH. Unexpectedly, Heat Shock Proteins (HSP90AA1, HSPA1A, HSPB1), G and RAS proteins, generally activated by stress situations were under-represented in aneurysmal walls. Further PCR and Western Blotting studies are needed to confirm such findings and to identify diagnostic and prognostic markers in order to define screening protocols for intracranial aneurysms.

Angioarchitectural features of brain arteriovenous malformations associated with seizures: a single center retrospective series.

BACKGROUND AND PURPOSE: Epileptic seizures account for 24-40% of all clinical onsets in patients with brain arteriovenous malformations (AVMs). METHODS: We retrospectively reviewed the angioarchitectural features of AVMs associated with seizures in 168 patients admitted to our Department from 1997 to 2012. Patients were dichotomized according to demographic characteristics, type of treatment, bleeding occurrence, and morphological and topographic features. Clinical status at admission and discharge was also recorded. The association of each one of these variables with seizures occurrence was statistically tested. Continuous variables and outcome were compared with Student's t-test, whereas categorical ones were compared using Fisher's exact test. The independent contribution of some seizures predictors was assessed with a logistic regression model. Associations were considered significant for P < 0.05. RESULTS: About 29% patients showed seizures and 47% bleeding. No significant difference in age and sex was observed between patients with and without seizures. AVMs > 4 cm (P = 0.001) and those fed by dilated arterial feeders (P = 0.02) were associated with increased risk of seizures. A higher risk of seizures occurrence was also observed in cortical AVMs compared with deeper ones (75.5% vs. 55.4%; P = 0.01), and in AVMs fed by middle and posterior cerebral arteries branches compared with the other vessels (81.6% vs. 45.3%; P < 0.001 and 48.9% vs. 23.5%; P = 0.002, respectively). No lobar predisposition was observed. A nidus > 4 cm also appeared as an independent risk factor of seizures occurrence (OR 2.82; 95% CI, 1.26-6.31; P = 0.009) at logistic regression analysis. CONCLUSIONS: AVM morphology, especially nidus dimension, appeared to more significantly influence seizures occurrence than their topography.

Neuroprotective strategies in hippocampal neurodegeneration induced by the neurotoxicant trimethyltin.

The selective vulnerability of specific neuronal subpopulations to trimethyltin (TMT), an organotin compound with neurotoxicant effects selectively involving the limbic system and especially marked in the hippocampus, makes it useful to obtain in vivo models of neurodegeneration associated with behavioural alterations, such as hyperactivity and aggression, cognitive impairment as well as temporal lobe epilepsy. TMT has been widely used to study neuronal and glial factors involved in selective neuronal death, as well as the molecular mechanisms leading to hippocampal neurodegeneration (including neuroinflammation, excitotoxicity, intracellular calcium overload, mitochondrial dysfunction and oxidative stress). It also offers a valuable instrument to study the cell-cell interactions and signalling pathways that modulate injury-induced neurogenesis, including the involvement of newly generated neurons in the possible repair processes. Since TMT appears to be a useful tool to damage the brain and study the various responses to damage, this review summarises current data from in vivo and in vitro studies on neuroprotective strategies to counteract TMT-induced neuronal death, that may be useful to elucidate the role of putative candidates for translational medical research on neurodegenerative diseases.

Nanotechnology and vascular neurosurgery: an in vivo experimental study on microvessels repair using laser photoactivation of a nanostructured hyaluronan solder.

Sealing tissues by laser in neurosurgical procedures may overcome problems related to the use of conventional suturing methods which can be associated with various degrees of vascular wall damage. Despite the significant experimental and clinical achievements of the past, a standardized clinical application of laser-welding technology has not yet been implemented. The main problem is related to the use of common organic chromophores. A substantial breakthrough in the laser welding of biological tissues may come from the advent of nanotechnologies. In this paper we describe an experimental study, to confirm the feasibility of an innovative laser-assisted vascular repair (LAVR) technique based on diode laser irradiation and subsequent photoactivation of a hyaluronan solder embedded with near infrared (NIR) absorbing gold nanorods (GNRs), and to analyze the induced closuring effect in a follow-up study performed in animal model. Twenty New Zealand rabbits underwent closure of a 3-mm longitudinal incision performed on the common carotid artery (CCA) by means of 810 nm diode laser irradiation, in conjunction with the topical application of an optimized GNR composite. Effective closure of the arterial wound was accomplished by using very low laser intensity (30 W/cm2). The average CCA occlusion time was as low as 50 sec. Animals underwent different follow-up periods (2, 8, 30 days). After follow-up, they were re-anesthetized, the patency of the treated vessels was tested (Doppler analysis) and then the irradiated vessels were excised and subjected to histological evaluations. Morphological examinations of the samples documented the integrity of the vascular wall. No host reaction to nanoparticles occurred. Collagen and elastic fibers returned to their normal architecture 30 days after treatment. A Scanning Electron Microscopy (SEM) examination and immuno-histochemical analysis demonstrated a full re-endothelization of the vessel walls. We thus confirmed that a laser-based approach is technically easy to perform, and provides several advantages, such as a simplification of the surgical procedure, a reduction in the operative time, and the suppression of bleeding. The use of GNRs improves the selectivity of welding and minimizes the surgical trauma to vessels, resulting in an optimal healing process.

Distribution and time-course of 4-hydroxynonenal, heat shock protein 110/105 family members and cyclooxygenase-2 expression in the hippocampus of rat during trimethyltin-induced neurodegeneration.

Trimethyltin (TMT), an organotin compound considered a useful tool to obtain an experimental model of neurodegeneration, exhibits neurotoxicant effects selectively localised in the limbic system and especially in the hippocampus, which are different in the rat and in mice. In the rat hippocampus, we investigated the expression of aldehyde 4-hydroxynonenal, a major bioactive marker of membrane lipid peroxidation, heat shock protein (HSP) 110/105 family members, markers of oxidative stress, and the neuroinflammatory marker cyclooxygenase-2 after TMT-intoxication at various time points after treatment. Our data show that TMT-induced neurodegeneration in the rat hippocampus is associated specifically with oxidative stress and lipid peroxidation, but not with HSP expression, indicating species-specific differences in the neurotoxicity of TMT between rats and mice.

A computational model to compare different investment scenarios for mini-stereotactic frame approach to deep brain stimulation surgery.

UNLABELLED: Deep brain stimulation (DBS) alleviates symptoms of many neurological disorders by applying electrical impulses to the brain by means of implanted electrodes, generally put in place using a conventional stereotactic frame. A new image guided disposable mini-stereotactic system has been designed to help shorten and simplify DBS procedures when compared to standard stereotaxy. A small number of studies have been conducted which demonstrate localization accuracies of the system similar to those achievable by the conventional frame. However no data are available to date on the economic impact of this new frame. AIM: The aim of this paper was to develop a computational model to evaluate the investment required to introduce the image guided mini-stereotactic technology for stereotactic DBS neurosurgery. METHODS: A standard DBS patient care pathway was developed and related costs were analyzed. A differential analysis was conducted to capture the impact of introducing the image guided system on the procedure workflow. The analysis was carried out in five Italian neurosurgical centers. RESULTS: A computational model was developed to estimate upfront investments and surgery costs leading to a definition of the best financial option to introduce the new frame. Investments may vary from Euro 1.900 (purchasing of Image Guided [IG] mini-stereotactic frame only) to Euro 158.000.000. Moreover the model demonstrates how the introduction of the IG mini-stereotactic frame doesn't substantially affect the DBS procedure costs.

Middle cerebral artery dolichoectasia in a young woman with a previous stroke.

We observed a 32-year-old female who had suffered from a left hemisphere ischemic stroke with right hemiparesis at the age of seven. At that time, a CT scan demonstrated a left ischemic lesion in nucleo-capsular region and a cerebral angiogram documented a complete occlusion of the supraclinoid segment of the internal carotid artery. When we observed the patient neurological examination demonstrated a moderate right brachio-crural hemiparesis. A brain MRI showed an old ischemic lesion involving the left nucleo-capsular and 'flow voids' suggestive for a vascular malformation in the left sylvian region. A cerebral rotational angiogram with 3-D reconstructions demonstrated a dolichoectatic left middle cerebral artery with an unusual 'corkscrew' aspect. Middle cerebral artery dolichoectasia is a rare pathological condition that may manifest with a stroke. The patients with intracranial arterial dolichoectasia (IADE) are most often hypertensive elderly men, and, to the best of our knowledge, an ischemic stroke associated with IADE has never been reported in children.

[Plastic industry and exposure to carcinogenic chemical agents: an Italian Multicentric Study in Lombardy]. / Stampaggio della plastica ed agenti chimici cancerogeni: l'esperienza dello studio PPTP-Plastica.

The potential carcinogenic risk at the workplaces is a primary interest of occupational health, but some questions are also controversially discussed. Particularly, in the plastic forming industry a great attention was directed to the hot processing and their possible exposure to monomers, some of which were classified as carcinogen by the International Agency for Research on Cancer (IARC) and/or the European Union (EU). In Lombardy, a study on occupational exposure to chemical carcinogens in the plastic forming industry was planned during last years. The aim was to recognize and promote preventive technical and medical solutions, basing on efficacy. By an investigation at workplace supported with standardized questionnaires, the presence of chemical carcinogens was registered in 59% of a representative sample of firms; but an effective possibility of exposure was found only for 34% of cases. The evaluation of exposure to monomers by air monitoring (acrylonitrile, 1,3-butadiene, styrene, formaldehyde), involving a representative sample of factory with ABS and formaldehydic resins processing, showed low level exposure, because the common hygienic prevention measures were applied; some particular occupation shoved greater exposure to formaldehyde.

Chronic anaemia and adhesion molecules in patients with liver cirrhosis. A preliminary report.

AIM: The aim of our study was to investigate circulating levels of intercellular adhesion molecule-1 (sICAM-1) and vascular cellular adhesion molecule-1 (sVCAM-1) in cirrhotic patients, with and without chronic anaemia, to establish whether there was a relationship between inflammatory activity and anaemia. METHODS: We investigated 14 anaemic (mean hemoglobin value 10.65+/-1.06 g/dL) and 14 non anaemic (mean hemoglobin value 13.8+/-0.89 g/dL) subjects affected by virus C-related liver cirrhosis comparable for sex, age and degree of liver dysfunction such as expressed by Child-Pugh classification. Circulating sICAM-1 and sVCAM-1 were measured by EIA commercial kit (R&D System Co, Abington, UK) and mean+/- standard deviation values in two groups were compared by t-test and Kruskall-Wallis test. RESULTS: Mean+/-standard deviation sICAM-1 was 35.06+/-4.06 ng/mL in anaemic and 23.39+/- 6.1 ng/mL in non anaemic cirrhotic patients. Mean+/-standard deviation sVCAM-1 was 47.66+/-8.18 ng/mL in anaemic 31.77+/-6.08 ng/mL in non anaemic patients, respectively. Statistical analysis showed a significant difference between the two groups both in sICAM-1 (p=0.01) and sVCAM-1 (p=0.03) values. CONCLUSIONS: Our study show that chronic anaemia, in liver cirrhosis, is associated to a greater increase of circulating adhesion molecules and suggests that inflammation may contribute to persistence of anaemic state, worsening the outcome of cirrhotic patients.

ICP and CBF regulation: effect of the decompressive craniectomy.

The view of the intracranial system as a rigid and closed box has been criticised by many authors who take into account the possibility of a certain degree of elastic bulk accommodation, mainly in the spinal sac. In nine patients, who underwent decompressive craniectomy for treatment of life-threatening intracranial hypertension, when the clinical conditions improved, just before cranioplasty, the blood flow velocities at middle cerebral artery (MCA) and at superior sagittal sinus (SSS) level were simultaneously recorded. The measurements were repeated after cranioplasty. The blood flow velocity recorded from SSS in craniectomized patients appeared flat, without evident pulsation; after cranioplasty a clear-cut pulsatile wave became again evident. The disappearance of a pulsatile shape in the blood flow velocity recorded from the SSS when the intracranial system was "open" and the reappearance of a pulsatile blood flow waveform after the "closure" of the skull confirm that the venous bed acts as a bulk compensatory system in order to maintain the intracranial volume absolutely constant.

Pharmacogenomic analysis of rhIL-11 treatment in the HLA-B27 rat model of inflammatory bowel disease.

Recombinant human interleukin-11 (rhIL-11) reduces the clinical signs and histological lesions of inflammatory bowel disease (IBD) in transgenic rats expressing the human major histocompatability complex (MHC) class I allele, HLA-B27. To elucidate the pharmacogenomic effects of rhIL-11 in this model, we examined the global gene expression pattern in inflamed colonic tissue before and following rhIL-11 treatment using oligonucleotide microarrays. In total, 175 disease-related genes were identified. Increased expression of genes involved in antigen presentation, cell death and inflammation, and decreased expression of metabolic genes was associated with disease. A total of 27 disease-related genes returned to normal expression levels following rhIL-11 treatment including the MHC class II gene RT1-DMbeta. rhIL-11 induced the expression of four intestinal epithelial growth factors. These gene expression patterns indicate that treatment of inflammatory bowel disease with rhIL-11 affects class II antigen processing and colonic epithelial cell proliferation and metabolism.