Using a novel source-localized phase regressor technique for evaluation of the vascular contribution to semantic category area localization in BOLD fMRI.

Numerous studies have shown that gradient-echo blood oxygen level dependent (BOLD) fMRI is biased toward large draining veins. However, the impact of this large vein bias on the localization and characterization of semantic category areas has not been examined. Here we address this issue by comparing standard magnitude measures of BOLD activity in the Fusiform Face Area (FFA) and Parahippocampal Place Area (PPA) to those obtained using a novel method that suppresses the contribution of large draining veins: source-localized phase regressor (sPR). Unlike previous suppression methods that utilize the phase component of the BOLD signal, sPR yields robust and unbiased suppression of large draining veins even in voxels with no task-related phase changes. This is confirmed in ideal simulated data as well as in FFA/PPA localization data from four subjects. It was found that approximately 38% of right PPA, 14% of left PPA, 16% of right FFA, and 6% of left FFA voxels predominantly reflect signal from large draining veins. Surprisingly, with the contributions from large veins suppressed, semantic category representation in PPA actually tends to be lateralized to the left rather than the right hemisphere. Furthermore, semantic category areas larger in volume and higher in fSNR were found to have more contributions from large veins. These results suggest that previous studies using gradient-echo BOLD fMRI were biased toward semantic category areas that receive relatively greater contributions from large veins

Monro-Kellie 2.0: The dynamic vascular and venous pathophysiological components of intracranial pressure

For 200 years, the ‘closed box’ analogy of intracranial pressure (ICP) has underpinned neurosurgery and neuro-critical care. Cushing conceptualised the Monro-Kellie doctrine stating that a change in blood, brain or CSF volume resulted in reciprocal changes in one or both of the other two. When not possible, attempts to increase a volume further increase ICP. On this doctrine’s “truth or relative untruth” depends many of the critical procedures in the surgery of the central nervous system. However, each volume component may not deserve the equal weighting this static concept implies. The slow production of CSF (0.35 ml/min) is dwarfed by the dynamic blood in and outflow (∼700 ml/min). Neuro-critical care practice focusing on arterial and ICP regulation has been questioned. Failure of venous efferent flow to precisely match arterial afferent flow will yield immediate and dramatic changes in intracranial blood volume and pressure. Interpreting ICP without interrogating its core drivers may be misleading. Multiple clinical conditions and the cerebral effects of altitude and microgravity relate to imbalances in this dynamic rather than ICP per se. This article reviews the Monro-Kellie doctrine, categorises venous outflow limitation conditions, relates physiological mechanisms to clinical conditions and suggests specific management options

Bibliometric Analysis of Turkey’s Research Activity in the Anatomy and Morphology Category from the Web of Science Database

Objective: The measurement of international publication activities is one of the essential indicators used to evaluate the scientific development level of countries. Although many studies are using the bibliometric method in the literature, it is seen that there are very few bibliometric studies in the field of anatomy. This study aimed to analyze the articles bibliometrically which conducted by researchers at institutions from Turkey and indexed in Science Citation Index Expanded (SCI-E) of the Web of Science database in the category of Anatomy and Morphology. Materials and Methods: According to 2019 data, journals in the Anatomy and Morphology category and indexed in the SCI-E were determined. Publications from Turkey that were published in these journals was determined. The full-texts of these articles were examined, and study types were defined. Also, VOSviewer software was used to create a collaboration and word co-occurrence network. Results: It was determined that there were 48,002 publications in 21 journals. It was found that 1,461 publications (3.04%) have at least one author from Turkey. The total number of citations was 11,728 for these publications. The average number of citations was 8.02±11.95. The radiological studies have increased statistically more than both experimental animal and cadaveric studies by years. In addition, it has been determined that the total number of articles, especially the radiological studies, has increased significantly over the years. Conclusion: The increase in the number of scientific studies in the field of anatomy is important in terms of the contribution of Turkey to literature in this area

Padrões de Dominância de Drenagem do Seio Transverso

Objetivo: Investigar o padrão de dominância de drenagem sinusal dural por meio da prevalência de variações anatômicas do ST em exames de angiografias digitais cerebrais. Métodos: Trata-se de um estudo do tipo transversal, observacional e retrospectivo, com amostragem do tipo não probabilístico por conveniência, realizado por meio da análise de 83 exames de angiografia digitais cerebrais em 2D. Resultados: No sexo masculino foi observado um padrão de dominância direito de 32,43%, um padrão de dominância do ST esquerdo de 8,11% e um padrão simétrico de 59,46%. No sexo feminino os percentuais foram de 32,61%, 6,52 e 60,87 para os padrões de dominância direito, esquerdo e simétrico do ST, respectivamente. Para todos os sujeitos o maior percentual foi o de dominância simétrico do ST, cerca de 60,24%. Conclusões: O padrão de drenagem do seio transverso mais prevalente identificado foi o simétrico, independente do sexo do indivíduo. Quando uma dominância foi identificada, o padrão direito foi o mais prevalente. A variação mais prevalente foi a hipoplasia do seio transverso esquerdo. Variações raras como a agenesia do ST foram encontradas. Não foram identificadas diferenças entre o sexo

Acoustics Provide Insight in the Neonatal Brain and Cerebral Perfusion

__Abstract__ \n \nThe incidence of preterm birth is increasing. Preterm infants are all infants born before 37 weeks \nof gestation. The incidence of preterm birth in the Netherlands is 7.8% of all deliveries, with \n1.4% very preterm infants (below 32 weeks of gestation). Advances in prenatal and neonatal \ncare have led to increased survival of infants born preterm, however neonatal morbidity is still \nof concern. \nPreterm brain injury leads to problems of cognition, attention and behavior in 25-50% and to \nmajor motor problems (e.g. cerebral palsy) in 5-10% 7. Various lesions are the neuropathological \nsubstrate of this encephalopathy, including periventricular leucomalacia (PVL), germinal matrix \nhemorrhage/intraventricular hemorrhage and neuronal/axonal deficits of cerebral white matter, \ncerebellum and basal ganglia. The prevalence in the literature of PVL or neuronal/axonal \ndeficits in preterm infants is 50% . \nDuring our study period 336 preterm infants below 29 weeks of gestation were admitted \nto Sophia\xe2\x80\x99s Children\xe2\x80\x99s hospital neonatal intensive care unit. Of these infants, 61 preterm infants \ndied during the neonatal period and 157 infants developed apparent brain injury (documented \nwith cranial ultrasound (CUS) or conventional Magnetic Resonance Imaging (MRI)). Data on \nlong term neurodevelopmental outcome will follow in subsequent years