Insight into the phylogeny and responses of species from the genus Sergia (Campanulaceae) to the climate changes predicted for the Mountains of Central Asia (a world biodiversity hotspot).

BACKGROUND: Together with other elevated areas, the Mountains of Central Asia are significantly threatened by ongoing climate change. The presence of refuges during the glaciations makes the region extremely rich in species, especially endemic ones. However, the limited potential for colonisation of other habitats makes rocky-related species with 'island-like' distribution, particularly vulnerable to climate change. To understand the processes underlying species response to climate warming, we assessed differences in ecological niches and phylogenetic relationship of two geographically disjunctive alpine species belonging to the genus Sergia. The taxa are considered Tertiary relicts, endemic to the Tian Shan and Pamir-Alai Mountains. To illustrate range dynamics and differences in occupied niches of Sergia species, we used Ecological Niche Modelling of current and future distribution. Whereas, to reconstruct the phylogenetic relationship within and between Sergia and other related Campanulaceae species from the region we used molecular data (ITS, cpDNA, DArTseq-derived SNPs). RESULTS: The results reveal that the genus Sergia is a polyphyletic group, and its representatives differ geographically, ecologically and genetically. Both S. regelii and S. sewerzowii constitute a common clade with Asyneuma group, however, S. sewerzowii is more closely related to Campanula alberti (a species that has never previously been considered closely related to the genus Asyneuma or Sergia) than to S. regelii. Sergia sewerzowii is adapted to lower elevations with higher temperatures, while S. regelii prefers higher elevations with lower temperatures. The future distribution models demonstrate a dramatic loss of S. regelii range with a shift to suitable habitats in higher elevations, while the potential range of S. sewerzowii increases and shifts to the north. CONCLUSIONS: This study shows that S. regelii and S. sewerzowii have a long and independent evolution history. Sergia regelii and S. sewerzowii significantly differ in realised niches. These differences are mirrored in the response of the studied endemics to future climate warming. As suitable habitats shrink, rapid changes in distribution can lead to species' range loss, which is also directly related to declines in genetic variability. The outcomes of this paper will help to more precisely assess the impact of climate changes on rocky-related plant species found in this world's biodiversity hotspot.

Alpine Extremophytes in Evolutionary Turmoil: Complex Diversification Patterns and Demographic Responses of a Halophilic Grass in a Central Asian Biodiversity Hotspot.

Diversification and demographic responses are key processes shaping species evolutionary history. Yet we still lack a full understanding of ecological mechanisms that shape genetic diversity at different spatial scales upon rapid environmental changes. In this study, we examined genetic differentiation in an extremophilic grass Puccinellia pamirica and factors affecting its population dynamics among the occupied hypersaline alpine wetlands on the arid Pamir Plateau in Central Asia. Using genomic data, we found evidence of fine-scale population structure and gene flow among the localities established across the high-elevation plateau as well as fingerprints of historical demographic expansion. We showed that an increase in the effective population size could coincide with the Last Glacial Period, which was followed by the species demographic decline during the Holocene. Geographic distance plays a vital role in shaping spatial genetic structure of P. pamirica alongside with isolation-by-environment and habitat fragmentation. Our results highlight a complex history of divergence and gene flow in this species-poor alpine region during the Late Quaternary. We demonstrate that regional climate specificity and a shortage of non-climate data largely impede predictions of future range changes of the alpine extremophile using ecological niche modelling. This study emphasises the importance of fine-scale environmental heterogeneity for population dynamics and species distribution shifts.

Significance of moss pretreatments in active biomonitoring surveys.

The present study examines the impact of pretreatment procedures on the metal concentrations in bags that are to be exposed. We examine Mn, Fe, Cu, Zn, Cd, and Pb amounts in Sphagnum fallax and Dicranum polysetum mosses using atomic absorption spectrometry. The concentration of Hg was also determined using a mercury analyzer. Two sample preparation ways were tested (with and without rinsing) and their influence was evaluated by determining the coefficient of variation (CV). Chlorophyll content was also determined in mosses collected from three habitats (deep woodland, forest road, and wood lot). The results indicate, that the concentration of elements deposited in mosses depends on the species and the habitat where they were collected (ANOVA, p < 0.001). Rinsing of mosses reduces the CV for Mn, Fe, Cu, and Zn and uniform the material prior to exposure (CV for the majority of metals <10%). Selected correlations were found for element concentrations with chlorophyll content. Photosynthetic activity of mosses decreased by about 80% during their one-month storage in the laboratory. Due to the varying concentration of metals in the collected samples, proper, and standardized preparation of mosses before exposure, they can be effectively used in active biomonitoring.

Compared to other biomonitoring work the novel approach is the simultaneous study of two moss species, the analysis of three different habitats and the tie-in of accumulated trace elements by mosses and their vitality by measuring chlorophyll content and photosynthetic activity.

Global models and predictions of plant diversity based on advanced machine learning techniques.

Despite the paramount role of plant diversity for ecosystem functioning, biogeochemical cycles, and human welfare, knowledge of its global distribution is still incomplete, hampering basic research and biodiversity conservation. Here, we used machine learning (random forests, extreme gradient boosting, and neural networks) and conventional statistical methods (generalized linear models and generalized additive models) to test environment-related hypotheses of broad-scale vascular plant diversity gradients and to model and predict species richness and phylogenetic richness worldwide. To this end, we used 830 regional plant inventories including c. 300 000 species and predictors of past and present environmental conditions. Machine learning showed a superior performance, explaining up to 80.9% of species richness and 83.3% of phylogenetic richness, illustrating the great potential of such techniques for disentangling complex and interacting associations between the environment and plant diversity. Current climate and environmental heterogeneity emerged as the primary drivers, while past environmental conditions left only small but detectable imprints on plant diversity. Finally, we combined predictions from multiple modeling techniques (ensemble predictions) to reveal global patterns and centers of plant diversity at multiple resolutions down to 7774 km2 . Our predictive maps provide accurate estimates of global plant diversity available at grain sizes relevant for conservation and macroecology.

Rooting depth and xylem vulnerability are independent woody plant traits jointly selected by aridity, seasonality, and water table depth.

Evolutionary radiations of woody taxa within arid environments were made possible by multiple trait innovations including deep roots and embolism-resistant xylem, but little is known about how these traits have coevolved across the phylogeny of woody plants or how they jointly influence the distribution of species. We synthesized global trait and vegetation plot datasets to examine how rooting depth and xylem vulnerability across 188 woody plant species interact with aridity, precipitation seasonality, and water table depth to influence species occurrence probabilities across all biomes. Xylem resistance to embolism and rooting depth are independent woody plant traits that do not exhibit an interspecific trade-off. Resistant xylem and deep roots increase occurrence probabilities in arid, seasonal climates over deep water tables. Resistant xylem and shallow roots increase occurrence probabilities in arid, nonseasonal climates over deep water tables. Vulnerable xylem and deep roots increase occurrence probabilities in arid, nonseasonal climates over shallow water tables. Lastly, vulnerable xylem and shallow roots increase occurrence probabilities in humid climates. Each combination of trait values optimizes occurrence probabilities in unique environmental conditions. Responses of deeply rooted vegetation may be buffered if evaporative demand changes faster than water table depth under climate change.

The Global Naturalized Alien Flora (GloNAF) database.

This dataset provides the Global Naturalized Alien Flora (GloNAF) database, version 1.2. GloNAF represents a data compendium on the occurrence and identity of naturalized alien vascular plant taxa across geographic regions (e.g. countries, states, provinces, districts, islands) around the globe. The dataset includes 13,939 taxa and covers 1,029 regions (including 381 islands). The dataset is based on 210 data sources. For each taxon-by-region combination, we provide information on whether the taxon is considered to be naturalized in the specific region (i.e. has established self-sustaining populations in the wild). Non-native taxa are marked as "alien", when it is not clear whether they are naturalized. To facilitate alignment with other plant databases, we provide for each taxon the name as given in the original data source and the standardized taxon and family names used by The Plant List Version 1.1 (http://www.theplantlist.org/). We provide an ESRI shapefile including polygons for each region and information on whether it is an island or a mainland region, the country and the Taxonomic Databases Working Group (TDWG) regions it is part of (TDWG levels 1-4). We also provide several variables that can be used to filter the data according to quality and completeness of alien taxon lists, which vary among the combinations of regions and data sources. A previous version of the GloNAF dataset (version 1.1) has already been used in several studies on, for example, historical spatial flows of taxa between continents and geographical patterns and determinants of naturalization across different taxonomic groups. We intend the updated and expanded GloNAF version presented here to be a global resource useful for studying plant invasions and changes in biodiversity from regional to global scales. We release these data into the public domain under a Creative Commons Zero license waiver (https://creativecommons.org/share-your-work/public-domain/cc0/). When you use the data in your publication, we request that you cite this data paper. If GloNAF is a major part of the data analyzed in your study, you should consider inviting the GloNAF core team (see Metadata S1: Originators in the Overall project description) as collaborators. If you plan to use the GloNAF dataset, we encourage you to contact the GloNAF core team to check whether there have been recent updates of the dataset, and whether similar analyses are already ongoing.

Predictors of Class I epilepsy surgery outcome in tumour-related chronic temporal lobe epilepsy in adults.

OBJECTIVE: Temporal lobe tumours, especially low-grade gliomas and glioneuronal tumours, are common causes of seizures in patients referred for epilepsy surgery. We here present our experience of surgical treatment of patients with intractable chronic epilepsy associated with temporal lobe tumours, focusing on the long-term surgical outcomes and the features associated with better seizure control. METHODS: In this study, we retrospectively analysed 44 consecutive patients from a total of 182 with refractory temporal lobe epilepsy presenting with long-term intractable epilepsy due to a temporal lobe tumour who were surgically treated at our institution between 2005 and 2015 with post-surgical follow-up of at least two years. All patients underwent a standard pre-surgical evaluation that included: history and physical examination with a description of the seizure semiology, serial scalp EEG recording, brain MR imaging, and a detailed neuropsychological evaluation. Our surgical strategy comprised tumour resection, and combined mesial temporal and neocortical resection in most cases. RESULTS: No patient died during surgery or the postoperative course. Seven patients had postoperative complications, of whom two had permanent hemiparesis due to ischaemic stroke. At the final follow-up, a favourable seizure outcome (Engel Class I) was found in 37 patients (84%), including 31 (70.5%) in Engel Class IA (excellent result). Two (4.5%) patients presented with an Engel Class II outcome (unfavourable outcome). Five patients (11.5%) were in Engel Classes III or IV (surgical failure). We found that complete resection of the hippocampus along with tumour and temporal pole removal was strongly associated with seizure freedom (p = 0.015). Pathological diagnosis was also a significant prognostic indicator of tumour-related seizure freedom. Patients with a diagnosis of a glioneuronal tumour benefited from more seizure freedom after resection compared to those who had a low-grade glioma (p = 0.024). CONCLUSION: The most appropriate management of tumour-related chronic temporal lobe epilepsy in adults appears to be tai-lored temporal lobe resection including tumour and hippocampal complex removal. Surgical treatment of tumoural temporal lobe epilepsy demonstrates excellent results in terms of seizure improvement, especially in patients with glioneuronal tumours.

Diffusion tensor tractography of pyramidal tracts in patients with brainstem and intramedullary spinal cord tumors: Relationship with motor deficits and intraoperative MEP changes.

PURPOSE: To evaluate whether pyramidal tracts course alterations observed in diffusion tensor tractography (DTT) in cases of brainstem and intramedullary spinal cord tumors reflect patient clinical status and prognosis. MATERIALS AND METHODS: For this purpose, we assessed in 17 patients relationships between pyramidal tracts course alterations observed in DTT (classified into four categories: unaffected; displaced or interspaced; partially disintegrated and completely disintegrated) performed on a 1.5 Tesla scanner and the presence of preoperative motor deficits, changes observed in motor evoked potentials (MEPs) records at the beginning of the operation, deterioration of the MEPs records during the operation, and perioperative deterioration of muscle strength. RESULTS: We found that, if the picture of pyramidal tracts in DTT was worse, motor deficit was more common (P = 0.062). This observation was even more evident (P = 0.027), when cases with at least partially destroyed pyramidal tracts were compared with cases with normal or at most displaced or interspaced by tumor but still preserved pyramidal tracts. Significant relationships were also found between changes in DTT and abnormal MEP records at the beginning of the operation (P = 0.032) and perioperative deterioration of muscle strength (P = 0.0058). CONCLUSION: A close relationship was found between pyramidal tracts course alterations in DTT imaging and preoperative motor status and especially with changes in the MEP records at the beginning of the operation. DTT may be a method that allows the better planning of brainstem and intramedullary spinal cord tumors operations and may help in the risk assessment of postoperative motor deficits. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 4 J. MAGN. RESON. IMAGING 2017;46:715-723.

Surgical treatment for spinal dural arteriovenous fistulas: Outcome, complications and prognostic factors.

BACKGROUND AND PURPOSE: Spinal dural arteriovenous fistulas (SDAVFs) are rare, acquired pathology and they inevitably lead to severe disability if untreated. The aim of this study is to present the outcome and complications, and to find factors that may affect the outcome after surgical treatment. METHODS: Seventeen consecutive patients (men - 14, women - 3, age: 41-79) were retrospectively analyzed. The patients presented with paraparesis (88%), bladder symptoms (71%) and/or sensory disturbances (65%). The fistula was found in the upper thoracic spine in 2 cases, in the lower thoracic (T7-Th12) in 11 cases, and in the lumbar spine in 4 cases. Microsurgical shunt interruption was performed in all, followed by epidural arteries coagulation in 12 cases. RESULTS: In the long term, improvement or achievement of a good stable condition was observed in 13 patients (76%), and no patient deteriorated. All 5 paraplegic patients improved by at least 1 grade in MCS. Satisfactory results (modified McCormick Scale grades I-II) were found in 10 patients (59%), and 15(88%) were independent. Postoperative complications occurred in 4 patients (24%), two of them (12%) required revision surgery for epidural hematoma. The success rate was 94%; one patient required revision surgery for recurrent SDAVF. Better neurological condition on admission (p=0.0098) and age >60 years (p=0.0498) were the factors associated with satisfactory outcome. CONCLUSIONS: Microsurgical closing of a SDAVF brings good and stable results over time. Aggressive treatment should be attempted even in cases of total loss of spinal cord function. Neurological condition before surgery and age may influence the outcome.

Epidermoid cysts of the cerebellopontine angle: Clinical features and treatment outcomes.

OBJECTIVE: To report clinical characteristics, treatment outcomes and risk of recurrence in patients with surgically treated cerebellopontine angle epidermoids. METHODS: In 1994-2013, we operated 17 patients, including 7 with tumor limited to the cerebellopontine angle, 7 with cerebellopontine angle tumor penetrating supratentorially, and 3 with cerebellopontine angle tumor extending along skull base to contralateral cerebellopontine angle. All patients were followed-up for the mean duration of 126 months. RESULTS: On admission cranial nerve symptoms predominated. Total tumor removal was achieved in 5 patients, and incomplete removal (with small tumor remnants left on vessels, nerves, or brainstem) in 12 patients. Postoperatively, preoperative deficits worsened in 2 and new postoperative deficits occurred in 10 patients. The extent of tumor expansion had no effect on postoperative morbidity and risk of recurrence. During long-term follow-up, improvement or resolution of preoperative deficits was seen in 11 of 17 patients, and new postoperative deficits in 8 of 10 patients. Symptomatic recurrences after an average of more than 9 years were noted in 5 patients, 3 of whom were reoperated. Recurrences occurred in some younger patients and always in area of primary tumor. No effect of extent of tumor removal on risk of recurrence was found. CONCLUSIONS: The extent of tumor removal had no effect on the risk of recurrence, and thus it may be acceptable to leave tumor capsule fragments adhering closely to nerves, vessels, or brainstem. During long-term follow-up, resolution or improvement of present preoperatively and new postoperative neurological deficits may be expected in most patients.

Surgery for sporadic vestibular schwannoma. Part II. Complications (not related to facial and auditory nerves).

INTRODUCTION: The aim of this study was to analyze the frequency and consequences of postoperative complications (PC) after surgery for sporadic vestibular schwannoma and to find factors that increase the risk of PC occurrence. MATERIALS AND METHODS: The study included 220 consecutive patients (134 women, 86 men; age ranged from 18 to 74) operated on with the retrosigmoid (217) or translabyrinthine (3) approach. Complicated postoperative period was defined as an occurrence of at least one of: cerebrospinal fluid (CSF) leakage, hematoma in the tumor bed, intracerebellar hematoma, cerebellar swelling, brainstem stroke, hydrocephalus (HCP), healing problems, meningitis and cranial nerves (excluding VII-VIII) palsies or cerebellar symptoms. Correlation studies and multivariate regression analysis were performed. RESULTS: PC occurred in 55 patients (25%). PC included lower cranial nerve (LCN) palsy (8.2%), cerebellar symptoms (7.3%), CSF leakage (5.9%), HCP (5%), CNVI palsy (3.1%), meningitis (1.8%), cerebellar swelling (1.4%), CNV dysfunction (0.9%), intracerebellar hematoma (0.5%) and lethal brainstem stroke (0.5%). In long term follow-up, LCN deficit was present in 2 patients (0.9%), cerebellar syndrome in 4(1.8%) and facial hypoesthesia in 2(0.9%). One patient (0.5%) developed bilateral blindness, secondary to preoperative optic nerve atrophy. As a result of PC, 10 patients (4.5%) required 11 additional surgical procedures. In statistical analysis, PC were independently related to preoperative cerebellar syndrome (p=0.002) and tumor size (>30 mm vs.<30 mm, p<0.05). The risk of PC diminished significantly with the increased number of performed procedures from 40% at the beginning to 16.4% in the last 55 cases. CONCLUSIONS: Tumor size, cerebellar syndrome at presentation and experience of the team were the three most important risk factors for PC occurrence. Permanent deficit secondary to PC remained in only 4% of the patients.

Surgery for sporadic vestibular schwannoma. Part I: General outcome and risk of tumor recurrence.

BACKGROUND: Vestibular schwannomas are slow growing, benign tumors. There are three possible management options: surgery, radiation treatment or active surveillance. The aim of this study was to assess the general outcome and risk of tumor recurrence. MATERIALS AND METHODS: The study included 220 consecutive patients (134 women, 86 men; the age ranged from 18 to 74) operated with the retrosigmoid transmeatal approach. The largest extrameatal diameter of the tumor ranged from 8 to 72mm (mean 30mm). According to the Samii grading scale, the tumors were classified as follows: T2-12 (6%), T3-51 (23%) and T4-157 (71%). Gross total resection was performed in 217 patients and neartotal in 3. RESULTS: Two hundred and eighteen (99.1%) patients were discharged home in a satisfactory neurological condition (GR or MD in GOS). One (0.5%) patient died due to brainstem infarction. One (0.5%) patient had unchanged severe cerebellar syndrome in comparison to the preoperative period (SD in GOS). In long-term follow-up, one patient went blind within a few months after surgery. Including the results of further neurosurgical procedures for CSF leak, shunt implantation, tumor regrowth and facial nerve reanimation, 98.6% of the patients were fully independent but with different neurological deficits. Tumor recurrence was observed in 5 (2.3%) patients during the follow-up period (mean term: 6.4 years). The average time to recurrence diagnosis was 8.8 years. All those patients were operated on again without any adjuvant therapy and there was no further re-growth at mean follow-up of 5.2 years. CONCLUSIONS: Complete removal of VS is usually curative and poses very low risks of severe disability (if audio-facial sequels are not included), mortality and long-term recurrence. For recurrent tumors, carefully tailored revision surgery without irradiation offers a high efficacy with low risk of complications.

Management of spinal tumors in neurofibromatosis type 2 patients.

OBJECTIVE: We sought to determine clinical characteristics of NF2 patients with spinal lesions and to define when and like the spinal tumors are a major problem in the treatment of patients with NF2. METHODS: The authors retrospectively reviewed the clinical records, neuroimaging studies, and follow-up data of the 34 patients with neurofibromatosis type 2, who were treated at our institution between 1998 and 2014. 23 patients harbored one or multiple spinal tumors. RESULTS: Patients with spinal tumors had a lower age at first symptoms of the disease, a higher number of intracranial meningiomas and non-vestibular schwannomas. 11 patients had one or more intramedullary tumors with MRI characteristics of spinal ependymomas. 22 patients had intradural extramedullary tumors. 7 patients presented with symptomatic spinal tumors on admission or developed symptoms during the follow-up. Only two intramedullary and four extramedullary tumors demonstrated growth in the mean radiological follow-up period of over 6 years. It was found that symptomatic both intra- and extramedullary tumors were associated with younger age at the onset of NF2-related symptoms. 2 patients with intramedullary tumors and 12 patients with extramedullary tumors underwent their tumors resection. In case of symptomatic tumors partial recovery was observed in two patients. CONCLUSION: It seems that close surveillance with MR imaging is a reasonable option for asymptomatic spinal tumors. Nevertheless, intramedullary tumor removal in non-growing and asymptomatic cases may be an option when ABI implantation is considered. Symptomatic tumors and those of documented growth should be eligible for surgical intervention.

Sensorimotor C5 and C6 radiculopathy caused by thrombosed vertebral artery dissection and successfully treated with limited oblique corpectomy - Case report.

The authors report the case of an exceptional presentation of vertebral artery dissection. A 44-year-old man who presented with left shoulder weakness, radicular pain and numbness of the left forearm and thumb was admitted to our hospital with an initial diagnosis of cervical disc herniation. Due to the inconsistency between the levels of radiculopathy (C5 and C6) and discopathy (C6-C7), neuroimaging examinations were extended. Based on MRI, MRA, CTA and DSA, left vertebral artery dissection with intramural hematoma was diagnosed. The patient underwent surgical decompression of the affected nerve roots using the anterolateral approach described by Bernard George. The radicular pain resolved immediately and sensorimotor deficit completely disappeared within 4 months. MRI/MRA performed 6 months after surgery showed the normal image of the vertebral artery. There were no ischemic events within 2.5 years of follow-up.

Oblique corpectomy for treatment of cervical spine epidural abscesses: Report on four cases.

BACKGROUND: Spinal epidural abscesses (SEAs) in cervical locations are particularly life-threatening. Currently, SEAs are widely treated with bony decompression, followed by internal stabilization in purulent osteomyelitis. However, recently, a growing number of studies have reported minimally invasive approaches without internal fixation. PURPOSE: We describe four patients with cervical SEAs that were evacuated by oblique corpectomy (OC) without fusion. METHODS: This study included two women and two men (aged 44-90) that received operations for removing ventral cervical SEAs. All patients presented with progressively increasing myelopathy, and 3 had severe comorbid conditions. In all cases, a multilevel OC without fusion was performed. The amount of bone resection was tailored to fit the needs of granulation removal, with an effort to retain as much of the vertebral bodies as possible. Then, pus was evacuated and debridement of granulation was performed, followed by rinsing and drainage. RESULTS: The neurological status of 3 patients improved significantly after surgery. At the last follow-up examination, one showed full recovery, and in two a minor residual deficit persisted. During mean follow-up of 5.5 years, no internal stabilization was necessary. The oldest patient was tetraplegic, and had several concomitant diseases. That patient died from sudden cardiac arrest on the third postoperative day. Oblique corpectomy did not affect the anterior or posterior column. Additionally, it provided a broad view of the ventral aspect of the spinal canal. CONCLUSIONS: Oblique corpectomy allows appropriate spinal cord decompression and granulation removal in the case of cervical spine epidural abscess, without sacrificing spinal stability.

Surgery for sporadic vestibular schwannoma. Part IV. Predictive factors influencing facial nerve function after surgery.

OBJECTIVE: To analyze the impact of various clinical, radiological and perioperative factors that could influence the facial nerve intraoperative disruption risk (CNVII-IDR) and its long-term function (CNVII-LTF) after vestibular schwannoma (VS) surgery. MATERIAL AND METHODS: The study included 212 patients operated on for sporadic VS with no history of previous treatment for VS or CNVII palsy. The mean size of the tumor was 30 mm. Gross (210) or near-total (2) resections were carried out using the retrosigmoid (210) or translabyrinthine (2) approach. Correlation studies and multivariate regression analysis (RA) were performed. RESULTS: In correlation studies, the CNVII-IDR was increased by: headaches and cerebellar ataxia if one of them was the first symptom of the tumor (33% and 29%, respectively, p=0.008); preoperative hydrocephalus (40% vs. 9%, p=0.01), tumor size >3 cm (18% vs. 5%, p<0.01), tumor volume >10 cm(3) (19% vs. 4%, p<0.01), right-sided location 15% vs. 6%, p=0.047), lateral "park-bench" position (19% vs. 5% for supine position, p<0.01) and the procedure order (16% for the first 106 procedures vs. 6% for the last 106 procedures, p<0.05). In RA the tumor volume (p=0.012), side of the tumor (p=0.028) and patient's position during surgery (p=0.016) independently affected the CNVII-IDR. The following factors correlated significantly with satisfactory CNVII-LTF (HB grades I-III): tumor stage

Hypertrophic pachymeningitis.

BACKGROUND: Hypertrophic pachymeningitis (HP) is a rare clinical entity characterized by diffuse or localized fibrous thickening of the dura mater. It is well known but rare especially in pediatric population disease of differing origins. The primary (idiopathic) form is diagnosed after excluding other possible etiologies. Similar results from magnetic resonance imaging (MRI) for patients with hypertrophic pachymeningitis and meningiomas may make the diagnosis confusing. Additionally, making a proper diagnosis without histological sampling can be difficult in some cases. CASE DESCRIPTION: We present a case of an 18-year-old boy diagnosed with hypertrophic pachymeningitis in the area of the hypoglossal canal. The diagnosis was made after a 2-month history of hypoglossal nerve palsy and dysphagia preceded by a middle ear infection. The patient was treated surgically with suspicion of meningioma, but no evidence of a tumor was found during the operation. The postoperative period was uneventful. At the latest check-up, MRI revealed regression of all previously observed pathological changes.

Clinical course and management of intracranial meningiomas in neurofibromatosis type 2 patients.

OBJECTIVE: The aim of this study is to evaluate our surgical experience with intracranial meningiomas in NF2 patients and provide knowledge of the natural history of these lesions. METHODS: We included in the natural growth study patients with the diagnosis of NF2 who harbored intracranial meningiomas and were observed for at least 1 year. Tumors that were resected before achieving long-term follow-up were excluded from this analysis. RESULTS: We found 118 intracranial meningiomas in 34 patients in our series. 8 meningiomas in 7 patients were symptomatic. It was found that with an increase in tumor volume, brain edema and with the tumor location at the skull base, meningiomas are more likely to be symptomatic. Univariate analysis revealed that tumor growth was associated with a younger age at the onset of NF2-related symptoms, greater initial tumor volume, brain edema and with the presence of intracranial non-vestibular schwannoma. Multivariate analysis showed that the probability of tumor growth is associated with prolonged follow-up time. De novo meningiomas exhibited a significantly higher growth rate than other meningiomas. These tumors were more frequent in patients with intracranial non-vestibular schwannoma and with increasing length of meningioma observation. CONCLUSION: Meningiomas occur in about half NF2 patients. Many of them exhibit slow growth and long remain asymptomatic, however, those associated with early onset of NF2 symptoms and other features of the disease severity should be monitored in case of clinical and radiological progression that may require surgical treatment.

Results of surgical treatment of anterior clinoidal meningiomas - our experiences.

OBJECTIVE: Presentation of our experience in the treatment of anterior clinoidal meningiomas, including evaluation of factors that may affect early and long-term treatment outcomes. METHODS: Thirty patients were operated with strategy of complete tumor resection using fronto-orbito-zygomatic approach. Outcomes were assessed by Glasgow Outcome Scale at discharge and by Karnofsky Performance Scale at follow-up. RESULTS: There were 6 tumors in group I, 20 in group II, and 4 in group III according to Al-Mefty classification. Complete tumor resection (Simpson I or II) was achieved in 19 patients, incomplete resection (Simpson IV) in 11: due to strict tumor adhesion to cerebral arteries in 5 and tumor extension to cavernous sinus in 6 cases. Operative mortality was 6.7%. Visual acuity improved in six among nine patients with impaired vision but in no one among nine patients with blindness. Normal life activity (80-100 KPS) could be carried out by 88% patients at follow-up. Recurrence was observed in two (11.8%) patients after radical removal and progression of residual tumor in two (25%) after subtotal resection. CONCLUSIONS: Complete tumor removal is possible with an acceptable risk of death and severe neurological deficits, except for cases with tumor extension to the cavernous sinus or strict tumor adhesion to cerebral arteries. Visual acuity improvement may be expected in two thirds of patients with impaired vision, but not in cases of blindness. In cases of incomplete tumor removal, use of stereotactic radiosurgery immediately after surgery seems justified.

Surgery for sporadic vestibular schwannoma. Part III: Facial and auditory nerve function.

OBJECTIVE: The aim of this analysis was to assess short-term and long-term outcomes with respect to the preservation of facial and auditory nerve function following surgery for sporadic vestibular schwannomas. MATERIAL AND METHODS: The study included 220 consecutive patients operated on with the retrosigmoid (217) or translabyrinthine (3) approach. The mean extrameatal diameter of the tumor was 30mm. In 217 patients, gross total resection was performed and near-total in 3. Before surgery, the facial nerve (CNVII) weakness was found in 18% of patients and only 20% had serviceable hearing. Intraoperative neurophysiological CNVII monitoring was routinely used (the last 211 procedures). Intraoperative monitoring of the cochlear nerve function was used when the preservation of hearing was attempted (45 procedures). RESULTS: The rate of CNVII continuity loss during surgery was 11%, however, this decreased to 6% in the second half of the series. Facial nerve function deteriorated, in 88% of the patients shortly after surgery. However, it improved in 87% in follow-up. Delayed CNVII palsy was found in 5% of the patients and had a good prognosis in 88%. Final satisfactory CNVII function (CNVII-SF, HB grades I-III) was achieved in 76% of the patients when excluding the anastomosis results, and 87% when including them. In recent years, the rate of CNVII-SF has risen to 94%. Non-serviceable hearing was preserved in 49% of the patients, on whom it was attempted. CONCLUSION: Considering the size of the tumors and extent of the resections, the preservation of CNVII function is currently very high. A close surveillance of CNVII function evolution following surgery is mandatory, as 2/3 of the patients discharged with deep paresis will need different face reanimation procedures. The preservation of useful hearing is still problematic, especially in patients with large tumors.