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The article presents a case study on a refined neuronavigation technique that diminishes bonework needed for exposure and marsupialization, minimizing risks of accidental harm to the internal carotid artery (ICA). The technique uses real-time intraoperative instrument of a drill. The technique allows safe creation of a direct canal toward the cyst just medial to the paraclival ICA.

Remodeling of neuronal structures and networks is believed to significantly contribute to (partial) restoration of functions after stroke. However, it has been unclear to what extent the brain reorganizes and how this correlates with functional recovery in relation to stroke severity. We applied serial resting-state functional MRI and diffusion tensor imaging together with behavioral testing to relate longitudinal modifications in functional and structural connectivity of the sensorimotor neuronal network to changes in sensorimotor function after unilateral stroke in rats.Wefound that gradual improvement of functions is associated with wide-ranging changes in functional and structural connectivity within bilateral neuronal networks, particularly after large stroke. Both after medium and large stroke, brain reorganization eventually leads to (partial) normalization of neuronal signal synchronization within the affected sensorimotor cortical network (intraregional signal coherence), as well as between the affected and unaffected sensorimotor cortices (interhemispheric functional connectivity). Furthermore, the bilateral network configuration shifts from subacutely increased "small-worldness," possibly reflective of initial excessive neuronal clustering and wiring, toward a baseline small-world topology, optimal for global information transfer and local processing, at chronic stages. Cortical network remodeling was accompanied by recovery of initially disrupted structural integrity in corticospinal tract regions, which correlated positively with retrieval of sensorimotor functions. Our study demonstrates that the degree of functional recovery after stroke is associated with the extent of preservation or restoration of ipsilesional corticospinal tracts in combination with reinstatement of interhemispheric neuronal signal synchronization and normalization of smallworld cortical network organization. [ABSTRACT FROM AUTHOR]

The article investigates rates of case fatality, long-term risk of hemorrhage, complications, and successful obliteration of brain arteriovenous malformations (AVMs) after interventional treatment. Results reveal that case fatality was 0.68 per 100 person-years overall, 1.1 following microsurgery, 0.50 following stereotactic radiosurgery (SRS), and 0.96 after embolization. Intracranial hemorrhage rates were 1.4 per 100 person-years overall, 0.18 after microsurgery, 1.7 after SRS, and 1.7 after embolization. The findings suggest that treatment of brain AVM remains related to considerable risks and incomplete efficacy.

Objective: Monitoring of healthcare-associated infection rates is important for infection control and hospital benchmarking. However, manual surveillance is time-consuming and susceptible to error. The aim was, therefore, to develop a prediction model to retrospectively detect drain-related meningitis (DRM), a frequently occurring nosocomial infection, using routinely collected data from a clinical data warehouse. Methods: As part of the hospital infection control program, all patients receiving an external ventricular (EVD) or lumbar drain (ELD) (2004 to 2009; n = 742) had been evaluated for the development of DRM through chart review and standardized diagnostic criteria by infection control staff; this was the reference standard. Children, patients dying <24 hours after drain insertion or with <1 day follow-up and patients with infection at the time of insertion or multiple simultaneous drains were excluded. Logistic regression was used to develop a model predicting the occurrence of DRM. Missing data were imputed using multiple imputation. Bootstrapping was applied to increase generalizability. Results: 537 patients remained after application of exclusion criteria, of which 82 developed DRM (13.5/1000 days at risk). The automated model to detect DRM included the number of drains placed, drain type, blood leukocyte count, C-reactive protein, cerebrospinal fluid leukocyte count and culture result, number of antibiotics started during admission, and empiric antibiotic therapy. Discriminatory power of this model was excellent (area under the ROC curve 0.97). The model achieved 98.8% sensitivity (95% CI 88.0% to 99.9%) and specificity of 87.9% (84.6% to 90.8%). Positive and negative predictive values were 56.9% (50.8% to 67.9%) and 99.9% (98.6% to 99.9%), respectively. Predicted yearly infection rates concurred with observed infection rates. Conclusion: A prediction model based on multi-source data stored in a clinical data warehouse could accurately quantify rates of DRM. Automated detection using this statistical approach is feasible and could be applied to other nosocomial infections. [ABSTRACT FROM AUTHOR]

This study shows a significant correlation between functional connectivity, as measured with resting-state functional magnetic resonance imaging (MRI), and neuroanatomical connectivity, as measured with manganese-enhanced MRI, in rats at 10 weeks after unilateral stroke and in age-matched controls. Reduced interhemispheric functional connectivity between the contralesional primary motor cortex (M1) and ipsilesional sensorimotor cortical regions was accompanied by a decrease in transcallosal manganese transfer from contralesional M1 to the ipsilesional sensorimotor cortex after a large unilateral stroke. Increased intrahemispheric functional connectivity in the contralesional sensorimotor cortex was associated with locally enhanced neuroanatomical tracer uptake, which underlines the strong link between functional and structural reorganization of neuronal networks after stroke. [ABSTRACT FROM AUTHOR]

Despite the success of functional imaging to map changes in brain activation patterns after stroke, spatiotemporal dynamics of cerebral reorganization in correlation with behavioral recovery remain incompletely characterized. Here, we applied resting-state functional magnetic resonance imaging (rs-fMRI) together with behavioral testing to longitudinally assess functional connectivity within neuronal networks, in relation to changes in associated function after unilateral stroke in rats. Our specific goals were (1) to identify temporal alterations in functional connectivity within the bilateral cortical sensorimotor system and (2) to elucidate the relationship between those alterations and changes in sensorimotor function. Our study revealed considerable loss of functional connectivity between ipsilesional and contralesional primary sensorimotor cortex regions, alongside significant sensorimotor function deficits in the first days after stroke. The interhemispheric functional connectivity restored in the following weeks, but remained significantly reduced up to 10 weeks after stroke in animals with lesions that comprised subcortical and cortical tissue, whereas transcallosal neuroanatomical connections were preserved. Intrahemispheric functional connectivity between primary somatosensory and motor cortex areas was preserved in the lesion border zone and moderately enhanced contralesionally. The temporal pattern of changes in functional connectivity between bilateral primary motor and somatosensory cortices correlated significantly with the evolution of sensorimotor function scores. Our study (1) demonstrates that poststroke loss and recovery of sensorimotor function is associated with acute deterioration and subsequent retrieval of interhemispheric functional connectivity within the sensorimotor system and (2) underscores the potential of rs-fMRI to assess spatiotemporal characteristics of functional brain reorganization that may underlie behavioral recovery after brain injury. [ABSTRACT FROM AUTHOR]

Context: Outcomes following treatment of brain arteriovenous malformations (AVMs) with microsurgery, embolization, stereotactic radiosurgery (SRS), or combinations vary greatly between studies. Objectives: To assess rates of case fatality, long-term risk of hemorrhage, complications, and successful obliteration of brain AVMs after interventional treatment and to assess determinants of these outcomes. Data Sources: We searched PubMed and EMBASE to March 1, 2011, and hand-searched 6 journals from January 2000 until March 2011. Study Selection and Data Extraction: We identified studies fulfilling predefined inclusion criteria. We used Poisson regression analyses to explore associations of patient and study characteristics with case fatality, complications, long-term risk of hemorrhage, and successful brain AVM obliteration. Data Synthesis: We identified 137 observational studies including 142 cohorts, totaling 13 698 patients and 46 314 patient years of follow-up. Case fatality was 0.68 (95% CI, 0.61-0.76) per 100 person-years overall, 1.1 (95% CI, 0.87-1.3; n = 2549) after microsurgery, 0.50 (95% CI, 0.43-0.58; n = 9436) after SRS, and 0.96 (95% CI, 0.67-1.4; n = 1019) after embolization. Intracranial hemorrhage rates were 1.4 (95% CI, 1.3-1.5) per 100 person-years overall, 0.18 (95% CI, 0.10-0.30) after microsurgery, 1.7 (95% CI, 1.5-1.8) after SRS, and 1.7 (95% CI, 1.3-2.3) after embolization. More recent studies were associated with lower case-fatality rates (rate ratio [RR], 0.972; 95% CI, 0.955-0.989) but increased rates of hemorrhage (RR, 1.02; 95% CI, 1.00-1.03). Male sex (RR, 0.964; 95% CI, 0.945-0.984), small brain AVMs (RR, 0.988; 95% CI, 0.981-0.995), and those with strictly deep venous drainage (RR, 0.975; 95% CI, 0.960-0.990) were associated with lower case fatality. Lower hemorrhage rates were associated with male sex (RR, 0.976, 95% CI, 0.964-0.988), small brain AVMs (RR, 0.988, 95% CI, 0.980-0.996), and brain AVMs with deep venous drainage (0.982, 95% CI, 0.969-0.996). Complications leading to permanent neurological deficits or death occurred in a median 7.4% (range, 0%-40%) of patients after microsurgery, 5.1% (range, 0%-21%) after SRS, and 6.6% (range, 0%-28%) after embolization. Successful brain AVM obliteration was achieved in 96% (range, 0%-100%) of patients after microsurgery, 38% (range, 0%-75%) after SRS, and 13% (range, 0%-94%) after embolization. Conclusions: Although case fatality after treatment has decreased over time, treatment of brain AVM remains associated with considerable risks and incomplete efficacy. Randomized controlled trials comparing different treatment modalities appear justified. [ABSTRACT FROM AUTHOR]