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Παρασκευή 24 Φεβρουαρίου 2017

Patient-Centered Care in Obstructive Sleep Apnea: A Vision for the Future

Obstructive sleep apnea is a common condition, with multiple potential neurocognitive, cardiovascular, and metabolic consequences. Efficacious treatment is available, but patient engagement is typically required for treatment to be effective. Patients with sleep apnea are phenotypically diverse and have individual needs, preferences, and values that impact treatment decisions. There has been a shift in obstructive sleep apnea management from diagnosis to chronic care management. Making treatment decisions that incorporate an individual patient's values and preferences and are personalized for that patient's biology has the potential to improve patient outcomes.

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Contralateral sensitive cross flap for reconstruction of a burned breast

Abstract

Several different approaches for reconstruction have been already described taking into account size and shape of the native breast, location and type of cancer, whether adjuvant radiation and/or chemotherapy is needed, patient's demographic information, and surgeon's preferences and experience. We report a case of reconstruction in burn patient using a breast sensitive perforator flap from the contralateral side. Thanks to the volume excess, the left side was large enough to reconstruct the affected side. A supero-medial pedicled reduction mammaplasty was performed on the left breast, and the excess inferior-part was elevated laterally and caudally off the pectoralis major. The flap was supplied by two perforators from the internal mammary vessels, and it was transposed to the right side after resection of the burned breast tissue. The right nipple-areola complex was left buried under the flap. After 2 months, the flap pedicle was deepithelialized, debulked, and passed through inframammary fold. The nipple-areola complex was released as a pedicled flap and sutured to the flap tissue approximately at the same level of the contralateral from the sternal notch. Preoperative sensitivity assessment demonstrated worst sensation of the right breast compared to the uninjured side. At 6 months, postoperatively, the patient could localize pressure and sensibility tested by the use of cotton wool and a pinprick test was quite normal. A clear improvement was observed in cutaneous pressure sensation thresholds over the time. At 12 months, she could recognize cotton wool and a pinprick. No changes were observed in the nipple-areola complex sensibility.

Level of Evidence: Level V, therapeutic study.



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CHCHD10 mutations in patients with amyotrophic lateral sclerosis in mainland China

Publication date: Available online 24 February 2017
Source:Neurobiology of Aging
Author(s): Shen Shen, Ji He, Lu Tang, Nan Zhang, Dongsheng Fan
Many genes have been found to be pathogenic for amyotrophic lateral sclerosis (ALS). Among them, the coiled-coil-helix-coiled-coil-helix domain containing 10 (CHCHD10) has been reported to play a controversial role in ALS. We examined the coding region of this gene in 424 unrelated Chinese sporadic ALS (SALS) subjects, 73 familial ALS (FALS) subjects, and 204 healthy controls using a PCR-direct sequencing strategy. Two types of variants were identified, and of these, one variant (g.877C>T, p. P23L) was identified to be damaging, and the other one was (g.648G>A) in intron. The mutation (g.877C>T, p. P23L) has been previously reported in a Chinese frontotemporal dementia (FTD) patient. Our study is the first to report the clinical heterogeneity of specific mutations in CHCHD10 in ALS in an Asian population and to report the possible new mutation hotspot. Our findings support the major role of CHCHD10 in the FTD-ALS disease spectrum and stress the importance of mitochondrial abnormalities in the pathogenesis of diseases in Asian cohorts.



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Convergent and divergent effects of apolipoprotein E ε4 and ε2 alleles on amygdala functional networks in non-demented older adults

Publication date: Available online 24 February 2017
Source:Neurobiology of Aging
Author(s): Liang Gong, Hao Shu, Cancan He, Qing Ye, Feng Bai, Chunming Xie, Zhijun Zhang
Traditionally, in the context of Alzheimer's disease (AD), the APOEε2 allele is a protective factor and the APOEε4 allele is a destructive factor. However, this inverse relationship has recently been challenged, and the neural mechanisms underlying the effects of APOE genotype on AD remain unclear. A resting-state functional magnetic resonance imaging study was conducted to investigate the effects of APOE genotype and age on amygdala functional connectivity (AFC) networks in 84 patients with amnestic mild cognitive impairment (aMCI) and 124 cognitively normal order adults. The results indicated that the APOEε2 and APOEε4 alleles produced convergent effects in the right AFC network but divergent effects in the left AFC network. As age increased, APOEε2 carriers showed stable AFC, whereas APOEε4 carriers exhibited decreased AFC in all participants. Furthermore, mediation analysis revealed that connectivity strength regulates the effects of APOE genotype and age on cognitive function in aMCI patients. Our findings suggest that the APOEε2 and APOEε4 alleles produce both convergent and divergent topological effects on brain function.



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Metronomic and metronomic-like therapies in neuroendocrine tumors – rationale and clinical perspectives

Publication date: Available online 24 February 2017
Source:Cancer Treatment Reviews
Author(s): Ioana Lambrescu, Simona Fica, Diana Martins, Francesca Spada, Chiara Cella, Emilio Bertani, Manila Rubino, Bianca Gibelli, Chiara Grana, Guido Bonomo, Luigi Funicelli, Davide Ravizza, Eleonora Pisa, Dario Zerini, Antonio Ungaro, Nicola Fazio
Metronomic therapy is characterized by the administration of regular low doses of certain drugs with very low toxicity. There have been numerous debates over the empirical approach of this regime, but fewest side effects are always something to consider in order to improve patients′ quality of life. Neuroendocrine tumors (NETs) are rare malignancies relatively slow-growing; therefore their treatment is often chronic, involving several different therapies for tumor growth control. Knowing that these tumors are highly vascularized, the anti-angiogenic aspect is highly regarded as something to be targeted in all patients harboring NETs. Additionally the metronomic schedule has proved to be effective on an immunological level, rendering this approach as a multi- targeted therapy. Rationalizing that advanced NETs are in many cases a chronic disease, with which patients can live for as long as possible, a systemic therapy with regular low doses and a very low toxicity is in many cases a judicious manner of pursuing stabilization. Metronomic schedule is usually correlated with chemotherapy in oncology, but other therapies, such as radiotherapy and biotherapy can be delivered in a metronomic like manner. This review describes clinical trials and case series involving metronomic therapies alone or in combination in patients with advanced NETs. Nowadays level of evidence about metronomic therapy in NETs is quite low, therefore future prospective clinical studies are needed to validate the metronomic approach in specific clinical settings.

Graphical abstract

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Extreme Pareto: The One Thing

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Publication date: March–April 2017
Source:Current Problems in Diagnostic Radiology, Volume 46, Issue 2
Author(s): P. Bhargava




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Upcoming Articles

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Publication date: March–April 2017
Source:Current Problems in Diagnostic Radiology, Volume 46, Issue 2





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In Recent Issues

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Publication date: March–April 2017
Source:Current Problems in Diagnostic Radiology, Volume 46, Issue 2





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Acute myeloid leukemia in a patient with thrombocytopenia with absent radii: A case report and review of the literature

Publication date: Available online 24 February 2017
Source:Hematology/Oncology and Stem Cell Therapy
Author(s): Maximilian Jameson-Lee, Katherine Chen, Ellen Ritchie, Tsiporah Shore, Omar Al-Khattab, Usama Gergis
Thrombocytopenia with absent radii (TAR) syndrome is a rare congenital disorder characterized by low platelet counts of various severity, bilateral absent radii but thumbs are usually present. TAR syndrome is not generally associated with bone marrow failure or malignancy. Janus kinase-2, myeloproliferative leukemia protein, and calreticulin are not mutated in TAR patients. Only four cases of leukemia were reported in TAR patients in the literature: three acute myeloid leukemia (AML) and one acute lymphoblastic leukemia. Of the three cases of AML found in TAR patient, only one was reported in an adult. We report a case of myelodysplastic syndrome progressing to AML with calreticulin driver mutation in an adult male with TAR syndrome who was successfully treated with hematopoietic allogeneic stem cell transplantation.



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Prefabrication of Vascularized Allogenic Bone Graft in a Rat by Implanting a Flow-Through Vascular Pedicle and Basic Fibroblast Growth Factor Containing Hydroxyapatite/Collagen Composite

J reconstr Microsurg
DOI: 10.1055/s-0037-1599077

Background Basic fibroblast growth factor (bFGF) is known to stimulate bone formation and angiogenesis. Hydroxyapatite/collagen composite (HAp/Col) is also known to have very strong bone conductive activity. In this study, prefabrication of vascularized allogenic bone (allo-bone) graft was attempted in recipients by implanting vascular bundles from recipients into the transplanted allo-bone graft. Furthermore, the effect of bFGF-containing HAp/Col on the prefabricated vascularized allo-bone graft was investigated. Methods In this study, 32 Sprague-Dawley rats were used as donors, and bone grafts were collected from their femora. Thirty-two Wistar rats (recipients) were divided into four groups, and the allo-bone grafts were transplanted into the thigh region. In the experimental groups, one or both of the flow-through saphenous vascular bundles and 100-μg bFGF-containing HAp/Col were implanted into the medullary cavity of the allo-bone grafts. In the control group, neither was implanted. These rats were sacrificed at 4 weeks after transplantation, and bone formation, angiogenesis, and bone resorption in the transplanted allo-bone grafts were evaluated histologically and genetically. Results Bone formation and angiogenesis in the transplanted allo-bone graft were effectively stimulated by implanting vascular bundles or bFGF-containing HAp/Col on both histological and genetic evaluations compared with the control group. The most significant stimulation was observed in the group in which both were implanted. Bone resorption was not stimulated in any group. Conclusion By implanting a flow-through vascular bundle and bFGF-containing HAp/Col, an ideal vascularized allo-bone graft that had high bone formative and angiogenetic activities and did not stimulate bone resorptive activity was prefabricated.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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Evaluation of the Relationship between Age and Outcome after Microvascular Reconstruction among Patients with Recurrent Head and Neck Squamous Cell Carcinoma

J reconstr Microsurg
DOI: 10.1055/s-0037-1598621

Background In patients with head and neck squamous cell carcinoma (HNSCC), disease recurrence remains a significant obstacle to long-term survival. If possible, surgical salvage with reconstruction remains the best treatment option for patients with recurrence. Currently, there is no literature discussing whether age should preclude microvascular reconstruction in these patients. We hypothesize that older age alone does not affect outcomes. Methods A retrospective chart review of patients with HNSCC at our institution between 2008 and 2015 was performed. Patients were included if they underwent simultaneous resection and flap reconstruction for recurrent HNSCC. Data collected included age, sex, primary site, type of reconstruction, previous treatments, postoperative complications (systemic and reconstructive), and overall survival. Results A total of 65 patients met inclusion criteria for the review: 42 (64.6%) patients ≤70 years and 23 (35.4%) patients > 70 years. Overall survival was not significantly different between the younger and older groups (p = 0.199). Five-year survival was 60.1% in the younger group and 46.8% in the older group. No significant difference was found in reconstructive complication rates (p = 0.179) or systemic complication rates (p = 0.241) between the two groups. Multivariate logistic regression analysis further showed no significant association between patients' age (≤70 years or > 70 years) and reconstructive complications (p = 0.396) or systemic complications (p = 0.119). Conclusion Age is not significantly associated with complications among patients undergoing resection and reconstruction for recurrent HNSCC. Microvascular reconstruction remains a feasible option in older patients with recurrent HNSCC. Advanced age alone should not preclude the surgical management of recurrent HNSCC.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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Systematic Review of the Surgical Treatment of Extremity Lymphedema

J reconstr Microsurg
DOI: 10.1055/s-0037-1599100

Background Although conservative management of lymphedema remains the first-line approach, surgery is effective in select patients. The purpose of this study was to review the literature and develop a treatment algorithm based on the highest quality lymphedema research. Methods A systematic literature review was performed to examine the surgical treatments for lymphedema. Studies were categorized into five groups describing excision, liposuction, lymphovenous anastomosis (LVA), vascularized lymph node transfer (VLNT), and combined/multiple approaches. Studies were scored for methodological quality using the methodological index for nonrandomized studies (MINORS) scoring system. Results A total of 69 articles met inclusion criteria and were assigned MINORS scores with a maximum score of 16 or 24 for noncomparative or comparative studies, respectively. The average MINORS scores using noncomparative criteria were 12.1 for excision, 13.2 for liposuction, 12.6 for LVA, 13.1 for VLNT, and 13.5 for combined/multiple approaches. Loss to follow-up was the most common cause of low scores. Thirty-nine studies scoring > 12/16 or > 19/24 were considered high quality. In studies measuring excess volume reduction, the mean reduction was 96.6% (95% confidence interval [CI]: 86.2–107%) for liposuction, 33.1% (95% CI: 14.4–51.9%) for LVA, and 26.4% (95% CI: − 7.98 to 60.8%) for VLNT. Included excision articles did not report excess volume reduction. Conclusion Although the overall quality of lymphedema literature is fair, the MINORS scoring system is an effective method to isolate high-quality studies. These studies were used to develop an evidence-based algorithm to guide clinical practice. Further studies with a particular focus on patient follow-up will improve the validity of lymphedema surgery research.
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Treatment Options for Bilateral Autologous Breast Reconstruction in Patients with Inadequate Donor-Site Volume

J reconstr Microsurg
DOI: 10.1055/s-0037-1599074

More than 250,000 women will be diagnosed with invasive breast cancer in the United States in 2017 alone. A large number of these patients will undergo mastectomy and will be candidates for immediate breast reconstruction. The most common reconstructive options are either implant-based or autologous tissue reconstruction, with the latter having been reported to have higher rates of long-term patient satisfaction, lower cost, and less postoperative pain. A subset of patients, however, may not be ideal candidates for autologous microsurgical reconstruction, for example, due to inadequate abdominal tissues, yet they may desire this reconstructive modality. This is particularly challenging in patients requiring bilateral reconstructions. In this article, the authors discuss the various reconstructive modalities that can be considered in patients who desire bilateral breast reconstruction, are not ideal candidates for autologous reconstruction, yet do not wish to rely solely on implant-based modalities.
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Venous Supercharging Reduces Complications and Improves Outcomes of Distally Based Sural Flaps

J reconstr Microsurg
DOI: 10.1055/s-0037-1598620

Background The use of distally based neurocutaneous sural flaps (DBNCSF) is one of the most common methods of reconstructing the distal lower leg. However, they have developed a bad reputation because of their propensity for venous engorgement. Venous congestion that can lead to distal necrosis can be prevented by venous supercharging. Using a prospective comparative study, we thus explored the effect of venous supercharging on the reliability of these useful workhorse flaps. Methods We prospectively included 38 patients who received a conventional DBNCSF and 38 patients who received a supercharged version of this flap (sDBNCSF) between January 2012 and July 2016. Results No significant difference was identified between the groups in terms of age, sex, comorbidity, or defect origin. The main reconstruction etiology was traumatic (open fracture, scar disunion, and chronic osteitis). The flap size was noticeably larger in the sDBNCSF group, albeit without significance. The length-width ratio was significantly greater in the sDBNCSF group (6.08 vs. 5.53, p = 0.022). Venous congestion was significantly more common in the non-supercharged group (28.6 vs. 2.6%, p = 0.01), as was coverage failure (23.7 vs. 2.6%, p = 0.035). Conclusion There are significant benefits to using venous supercharging of DBNCSF, when technically feasible. In our experience, venous supercharging increases reliability, allows the raise of larger skin paddles with much narrower pedicles limiting the morbidity of the procedure, and improves the functional and esthetic results.
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National Breast Reconstruction Utilization in the Setting of Postmastectomy Radiotherapy

J reconstr Microsurg
DOI: 10.1055/s-0037-1598201

Background Immediate breast reconstruction (IBR) is often deferred, when postmastectomy radiotherapy (PMRT) is anticipated, due to high complication rates. Nonetheless, because of robust data supporting improved health-related quality of life associated with reconstruction, physicians and patients may be more accepting of tradeoffs. The current study explores national trends of IBR utilization rates and methods in the setting of PMRT, using the National Cancer Database (NCDB). The study hypothesis is that prosthetic techniques have become the most common method of IBR in the setting of PMRT. Methods NCDB was queried from 2004 to 2013 for women, who underwent mastectomy with or without IBR. Patients were grouped according to PMRT status. Multivariate logistic regression was used to calculate odds of IBR in the setting of PMRT. Trend analyses were done for rates and methods of IBR using Poisson regression to determine incidence rate ratios (IRRs). Results In multivariate analysis, radiated patients were 30% less likely to receive IBR (p < 0.05). The rate increase in IBR was greater in radiated compared with nonradiated patients (IRR: 1.12 vs. 1.09). Rates of reconstruction increased more so in radiated compared with nonradiated patients for both implants (IRR 1.15 vs. 1.11) and autologous techniques (IRR 1.08 vs. 1.06). Autologous reconstructions were more common in those receiving PMRT until 2005(p < 0.05), with no predominant technique thereafter. Conclusion Although IBR remains a relative contraindication, rates of IBR are increasing to a greater extent in patients receiving PMRT. Implants have surpassed autologous techniques as the most commonly used method of breast reconstruction in this setting.
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Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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Impact of Preoperative Computed Tomography Angiogram on Abdominal Flap Breast Reconstruction Outcomes: A Systematic Review

J reconstr Microsurg
DOI: 10.1055/s-0037-1598617

Introduction CT angiogram (CTA) is widely believed to improve operative time and flap outcomes for perforator flap breast reconstruction, but the quality of the evidence is not known. We conducted a systematic review of the efficacy of preoperative CTA for abdominal perforator flap breast reconstruction. Methods Inclusion criteria included published articles in English, CTA group, and control group, between 2000 and March 2013. Medline and PubMed were queried. Study quality criteria were developed based on standards of internal and external validity. One reviewer screened titles and abstracts. Two authors independently reviewed the full-text articles. Outcomes of interest were operative time and flap outcomes. Results Ten publications met inclusion criteria. Study designs included retrospective or mixed prospective-retrospective cohorts. In every study, the control group time period preceded the CTA group time period and no studies adjusted for improved surgical skill (i.e., learning curve effect). Sample sizes ranged from 41 to 357. Five studies did not perform or provide statistical analysis for the results presented. The mean quality rating was 2.8 (out of a maximum of 7). Seven of 10 studies found a shorter operative time with CTA. Two of nine studies found fewer partial flap failures with CTA. Conclusion CTA is associated with shorter operative time, but some of this may be due to a learning curve effect. The evidence does not show a difference in flap outcomes. The evidence in support of preoperative CTA is limited and subject to bias due to study design.
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Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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Clinical Efficacy and Safety of Negative-Pressure Wound Therapy on Flaps: A Systematic Review

J reconstr Microsurg
DOI: 10.1055/s-0037-1599076

Background Although flap transfer is a popular reconstructive procedure with a high success rate, it is associated with a high complication rate and low salvage rate. During the past decade, negative-pressure wound therapy (NPWT) has been increasingly applied to facilitate flap transfer and salvage flaps threatened by complications. It has achieved some success, but its efficacy and safety remain controversial because of the limited number of reports and lack of systematic reviews. Methods English-language articles describing the application of NPWT on flaps were screened using predetermined inclusion and exclusion criteria. The articles were summarized and divided into groups based on the purpose of NPWT application. The complication rate, success rate, and salvage rate were obtained. Results Among the 3,395 articles searched, 16 articles describing 137 flaps were eligible. NPWT was applied on 105 (76.4%) newly transferred flaps to facilitate flap attachment and on 32 (23.4%) complication-threatened flaps to relieve flap infection and venous congestion. In total, complications developed in six flaps, three of which were lost; thus, the complication rate was 5.7% (6/105) and the success rate was 97.1% (102/105). Only 1 of the 32 threatened flaps was not successfully salvaged; thus, the salvage rate was 96.9% (31/32). Conclusion NPWT may facilitate flap transfer with few side effects and help to rescue flaps threatened by infection and venous congestion with a high salvage rate. Further studies are needed to test the safety of NPWT application on flaps with arterial compromise.
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Cortisol as a predictor of psychological therapy response in anxiety disorders − systematic review and meta-analysis

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Publication date: Available online 24 February 2017
Source:Journal of Anxiety Disorders
Author(s): Susanne Fischer, Anthony J. Cleare
BackgroundAlthough psychotherapy generally is effective in anxiety disorders, many patients are treatment-resistant. At the same time, some patients with anxiety disorders show alterations in the hypothalamic-pituitary-adrenal (HPA) axis, one of the major stress-responsive systems. Since raised levels of the end product of the HPA axis, cortisol, adversely affect cognition, we hypothesised that more pronounced alterations in cortisol levels would be associated with a less favourable response to psychotherapy. More specifically, the higher patients' basal levels and the lower their levels during exposure, the less likely we expected them to profit from treatment.MethodsWe systematically searched the Cochrane Library, EMBASE, MEDLINE, and PsycINFO to review the literature and perform a meta-analysis on the relationship between pre-treatment cortisol and psychotherapy response. Records were included if they studied patients with any anxiety disorder undergoing psychotherapy, with a pre-treatment cortisol and a post-treatment symptom measure. Correlation coefficients were extracted for meta-analyses.ResultsWe identified six studies (N=274). No relationship between patients' basal cortisol and post-treatment symptoms was found (p=.981). The systematic review showed higher cortisol during exposure sessions to predict better outcomes. Meta-analysis did not confirm this (p=.603).ConclusionsBasal cortisol did not seem to predict psychological therapy responses in patients with anxiety disorders. By contrast, the current state of research is equivocal in terms of whether higher cortisol concentrations during exposure sessions are linked with better treatment outcomes, and more research is needed to investigate this.



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Hierarchical control of procedural and declarative category-learning systems

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Publication date: 15 April 2017
Source:NeuroImage, Volume 150
Author(s): Benjamin O. Turner, Matthew J. Crossley, F. Gregory Ashby
Substantial evidence suggests that human category learning is governed by the interaction of multiple qualitatively distinct neural systems. In this view, procedural memory is used to learn stimulus-response associations, and declarative memory is used to apply explicit rules and test hypotheses about category membership. However, much less is known about the interaction between these systems: how is control passed between systems as they interact to influence motor resources? Here, we used fMRI to elucidate the neural correlates of switching between procedural and declarative categorization systems. We identified a key region of the cerebellum (left Crus I) whose activity was bidirectionally modulated depending on switch direction. We also identified regions of the default mode network (DMN) that were selectively connected to left Crus I during switching. We propose that the cerebellum—in coordination with the DMN—serves a critical role in passing control between procedural and declarative memory systems.



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HIgh b-value and high Resolution Integrated Diffusion (HIBRID) imaging

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Publication date: 15 April 2017
Source:NeuroImage, Volume 150
Author(s): Qiuyun Fan, Aapo Nummenmaa, Jonathan R. Polimeni, Thomas Witzel, Susie Y. Huang, Van J. Wedeen, Bruce R. Rosen, Lawrence L. Wald
The parameter selection for diffusion MRI experiments is dominated by the "k-q tradeoff" whereby the Signal to Noise Ratio (SNR) of the images is traded for either high spatial resolution (determined by the maximum k-value collected) or high diffusion sensitivity (effected by b-value or the q vector) but usually not both. Furthermore, different brain regions (such as gray matter and white matter) likely require different tradeoffs between these parameters due to the size of the structures to be visualized or the length-scale of the microstructure being probed. In this case, it might be advantageous to combine information from two scans – a scan with high q but low k (high angular resolution in diffusion but low spatial resolution in the image domain) to provide maximal information about white matter fiber crossing, and one low q but high k (low angular resolution but high spatial resolution) for probing the cortex.In this study, we propose a method, termed HIgh b-value and high Resolution Integrated Diffusion (HIBRID) imaging, for acquiring and combining the information from these two complementary types of scan with the goal of studying diffusion in the cortex without compromising white matter fiber information. The white-gray boundary and pial surface obtained from anatomical scans are incorporated as prior information to guide the fusion. We study the complementary advantages of the fused datasets, and assess the quality of the HIBRID data compared to either alone.



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