Diagnosis of osteoporotic vertebral fractures in children

Abstract

Osteoporosis is a generalised disorder of the skeleton with reduced bone density and abnormal bone architecture. It increases bone fragility and renders the individual susceptible to fractures. Fractures of the vertebrae are common osteoporotic fractures. Vertebral fractures may result in scoliosis or kyphosis and, because they may be clinically silent, it is imperative that vertebral fractures are diagnosed in children accurately and at an early stage, so the necessary medical care can be implemented. Traditionally, diagnosis of osteoporotic vertebral fractures has been from lateral spine radiographs; however, a small number of studies have shown that dual energy x-ray absorptiometry is comparable to radiographs for identifying vertebral fractures in children, while allowing reduced radiation exposure. The diagnosis of vertebral fractures from dual energy x-ray absorptiometry is termed vertebral fracture assessment. Existing scoring systems for vertebral fracture assessment in adults have been assessed for use in children, but there is no standardisation and observer reliability is variable. This literature review suggests the need for a semiautomated tool that (compared to the subjective and semiquantitative methods available) will allow more reliable and precise detection of vertebral fractures in children.

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Seguimiento de pilomatrixoma maligno metastásico agresivo mediante PET/TC con 18F-FDG

Publication date: Available online 10 November 2018

Source: Revista Española de Medicina Nuclear e Imagen Molecular

Author(s): Nese Torun, Emine Tuba Canbolat

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Prevalence of human papillomavirus in oral rinse samples from healthy individuals in northern Thailand

Abstract

Background

The incidence of oral cancers associated with human papillomavirus (HPV) has been increasing in recent years. Therefore, it is necessary to elucidate HPV prevalence in oral cells and exposure to risk factors in various age groups.

Methods

Oral rinse samples from healthy individuals in northern Thailand were investigated for HPV prevalence and genotyped using the polymerase chain reaction (GP5+/6+ primers) and DNA sequencing of the PCR products.

Results

Samples were collected from 594 participants between 4 and 60 years of age. HPV was detected in 3.7% of samples: there was no gender difference. The prevalence of HPV positive cases was 8.6% in the 31 ‐50 age group. HPV prevalence increased with age and was the highest (9.2%) in the 41‐50 age group, but decreased (to 3%) in the 51‐60 age group. Risk factors significantly associated with HPV‐positive cases included alcohol consumption, coffee drinking, sexual activity and having children. HPV 16 and 18 were common genotypes, especially in the 31‐50 age group, and were associated with having sexual activity [odds ratio 19.0 (95% CI: 2.5‐142.5)]. At follow‐up of some individuals in the 4‐10 age group, a 9‐year‐old child was found to be positive for HPV18.

Conclusions

These results suggest that HPV can be acquired at a young age and the prevalence peaks in the middle age class among healthy individuals in northern Thailand, especially in the 31‐50 age group.

This article is protected by copyright. All rights reserved.

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Dividing neutrophils in subsets, reveals a significant role for activated neutrophils in the development of airway hyperreactivity

Abstract

Background

Previous research has emphasized the importance of eosinophils in allergic asthma, while paying less attention to neutrophils. The known functionality of neutrophils in the inflammatory process has recently changed and knowledge about subsets of neutrophils, as characterized by their expression of CD16 and CD62L, has surfaced. Their specific roles in asthma are still unknown.

Objective

To study the functional differences between subsets of neutrophils by characterising the impact of individual subsets on airway smooth muscle reactivity.

Methods

The direct effect of neutrophils on airway hyper‐responsiveness was assessed by co‐culturing different subsets of neutrophils (produced by LPS in vitro stimulation) with human isolated small airways or murine tracheae with subsequent evaluation of smooth muscle reactivity to bradykinin in myographs. Supernatants and tissue were saved for ELISA and immunohistochemistry.

Results

The CD16^highCD62L^dim neutrophils were found to enhance the response to bradykinin in both human isolated small airways and murine tracheae. No such effects were obtained for the other subsets. The response is due to an upregulation of bradykinin receptor 2 through release of TNFα from the neutrophil.

Conclusions & Clinical Relevance

The present study introduces a new concept regarding the role of neutrophils and defines a novel direct link between a specific activated neutrophil subset and airway smooth muscle, establishing neutrophils as important players in the development of asthmatic airway hyperactivity.

This article is protected by copyright. All rights reserved.

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Variability of blood eosinophils in patients in a clinic for severe asthma

Abstract

Background

Blood eosinophils are used to determine eligibility for agents targeting IL‐5 in patients with uncontrolled asthma. However, little is known about the variability of blood eosinophil measures in these patients before treatment initiation.

Objective

To characterize variability and patterns of variability of blood eosinophil levels in a real‐world clinic for severe asthmatics.

Methods

Retrospective review of blood eosinophils measured over a 5‐year period in patients enrolled in an urban clinic. Repeated measures of blood eosinophil levels in individuals were evaluated and cluster analysis was performed to characterize patients by eosinophil patterns. Clinical characteristics associated with eosinophil levels and patterns of variability were analyzed.

Results

Patients treated in the Bellevue Hospital Asthma Clinic within a 3‐month period were identified (n = 219). Blood eosinophil measures were obtained over the previous 5 years. Only 6% (n= 13) of patients had levels that were consistently above 300 cells/μL. Nearly 50% (n = 104) had eosinophil levels that traversed the threshold of 300 cells/μL. In contrast, 102 (46%) had levels that never reached the threshold of 300 cells/μL. Cluster analyses revealed three clusters with differing patterns of levels and variability. There was a suggestion of decreased clinical control and increased atopy in the cluster with the greatest variability in blood eosinophil measures.

Conclusion

In an urban clinic for patients referred for uncontrolled asthma, blood measures of eosinophils were variable and showed differing patterns of variability. These data reinforce the need to perform repeated eosinophil blood measures for appropriate designation for therapeutic intervention.

This article is protected by copyright. All rights reserved.

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Traffic‐related air pollution induces non‐allergic eosinophilic airway inflammation and cough hypersensitivity in guinea pigs

Abstract

Background

The pathogenesis and pathophysiology of eosinophilia‐related chronic cough such as non‐asthmatic eosinophilic bronchitis and cough variant asthma are still not clear.

Objective

This study is to examine the potential role of traffic‐related air pollution (TRAP) in eosinophilic inflammation and cough responses.

Methods

Non‐sensitized guinea pigs were exposed to TRAP in an urban traffic tunnel or kept in a filtered air environment for 7 or 14 days. Reflexive cough was measured using citric acid and allyl isothiocyanate (AITC) challenges, respectively. Spontaneous cough counting was determined using audio recording and a waveform analysis. Airway inflammation was evaluated using differential cells in bronchoalveolar lavage fluid (BALF) and lung histopathology. To further elucidate the relationship between airway inflammation and cough hypersensitivity, a subgroup of those exposed for 14 days received a dexamethasone treatment.

Results

Compared to reflexive cough count (mean (95% confidence interval) in 10 min) provoked by the AITC challenge for the unexposed animals (3.1 (1.7‐4.5)), those were increased significantly following both the 7‐day (12.0 (6.8‐17.2), p<0.01) and the 14‐day (12.0 (6.4‐17.6), p<0.01) TRAP exposure. The effect provoked by the citric acid challenge was more profound following the 14‐day exposure (26.0 (19.5‐32.5) vs. 3.8 (1.5‐6.0) for the control, p<0.001). TRAP exposures enhanced spontaneous cough events, caused a significant increase of eosinophils and neutrophils in BALF, and resulted in a dramatic eosinophilic infiltration in submucosal layer of trachea and bronchus, which can be inhibited significantly by dexamethasone treatment.

Conclusions & Clinical Relevance

TRAP exposures induced cough hypersensitivity and non‐allergic eosinophilic inflammation of airways in guinea pigs. This study highlights the potential mechanisms of eosinophilia‐related chronic cough that can be induced by traffic‐related air pollution.

This article is protected by copyright. All rights reserved.

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Antihistamine‐resistant chronic spontaneous urticaria: 1‐year data from the AWARE study

Abstract

Background

Previous reports indicate that patients with chronic spontaneous urticaria (CSU) are undertreated and that physicians show poor adherence to guideline recommendations. Awareness of CSU has improved in recent years, but it remains unclear if this has improved the management of these patients in clinical practice.

Objective

To describe disease burden, quality of life (QoL), and treatment patterns of patients with H₁‐antihistamine‐refractory CSU in Germany.

Method

AWARE (A World‐wide Antihistamine‐Refractory chronic urticaria patient Evaluation) is a global prospective, non‐interventional study of chronic urticaria in the real‐world setting, supported by the manufacturer of omalizumab. Patients (18–75 years) were included who had H₁‐antihistamine‐refractory CSU for ≥2 months. Disease characteristics, pharmacological treatments, and QoL (dermatology life quality index [DLQI], chronic urticaria QoL questionnaire, and angioedema QoL questionnaire) are reported for patients enrolled in Germany.

Results

After 1 year in AWARE, CSU remained uncontrolled (urticaria control test [UCT] score <12) in 432 of 1032 (42.2%) patients. QoL impairment remained high after one year, with 28.2% of patients reporting that CSU had a moderate/very large/extremely large effect on the DLQI. Most patients did not receive guideline‐recommended treatments at the end of the one‐year observation period. Changes in treatments were most evident at the first patient visit, with an increase in patients receiving omalizumab vs. prior therapy from 8.5% to 21.4%, and a decrease in those receiving no treatment from 29.9% to 12.8%. These changes were associated with reduced hives, angioedema, UCT scores, and QoL scores at Month 3, but only modest improvements thereafter. Of 528 patients with uncontrolled CSU and who were eligible for treatment escalation, only 3% received up‐dosing of H₁‐antihistamines and only 5% were initiated on omalizumab during one year of treatment.

Conclusions & Clinical Relevance

This study highlights a significant discrepancy between recommendations for managing CSU in international guidelines, and in real‐world clinical practice in Germany.

This article is protected by copyright. All rights reserved.

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Bidirectional roles of IL-22 in the pathogenesis of allergic airway inflammation

Publication date: Available online 10 November 2018

Source: Allergology International

Author(s): Takashi Ito, Koichi Hirose, Hiroshi Nakajima

Abstract

Asthma is the most prevalent allergic disease of the airway, which is characterized by eosinophilic inflammation, mucus hyperproduction, and airway hyper-responsiveness. Although these pathognomonic features are mainly mediated by antigen-specific Th2 cells and their cytokines, such as IL-4, IL-5, and IL-13, recent studies have revealed that other inflammatory cells, including Th17 cells and innate lymphoid cells (ILCs), also play a critical role in the pathogenesis of asthma. IL-22, one of the cytokines produced by Th17 cells and type 3 ILCs, has distinct functional properties, as IL-22 exclusively acts on non-hematopoietic cells including epithelial cells of mucosal surface and exhibits a broad range of action in regeneration and host protection. In accordance with the fact that lung epithelial cells play a critical role in the pathogenesis of asthma, we and other groups have shown that IL-22 is involved in the regulation of allergic airway inflammation. In this review, we discuss recent advances in the biology of IL-22 and its involvement in the pathogenesis of allergic airway inflammation.

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Editorial Board

Publication date: November–December 2018

Source: Journal of Communication Disorders, Volume 76

Author(s):

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Immediate Effects of the Semi-Occluded Ventilation Mask on Subjects Diagnosed With Functional Dysphonia and Subjects With Normal Voices

Publication date: Available online 10 November 2018

Source: Journal of Voice

Author(s): Kharina Frisancho, Lukas Salfate, Karla Lizana, Marco Guzman, Fernando Leiva, Camilo Quezada

Abstract

Purpose

The present study was designed to assess the immediate effects of the semi-occluded ventilation mask (SOVM) in subjects with functional dysphonia and subjects with normal voice.

Methods

Sixty-four participants were included in this study (48 women and 16 men). Thirty-one of them were diagnosed with functional dysphonia and 33 with normal voice. All subjects were randomly assigned to one of two conditions: an experimental condition using the SOVM (n = 33) and a control condition with participants not using the SOVM (n = 31). Thus, within both conditions, participants could be either dysphonic or normal-voiced. This produced a total of four different groups: (1) subjects with normal voice with SOVM (n = 17), (2) subjects with normal voice without SOVM (n = 16), (3) dysphonic subjects with SOVM (n = 16), and (4) dysphonic subjects without SOVM (n = 15). All participants underwent aerodynamic, electroglottographic (EGG), and acoustic assessments, and were also asked to assess their own voice, before and after voice exercises.

Results

Significant differences were found for aerodynamic, EGG, and acoustic variables when comparing SOVM conditions (dysphonic and normal) against control. Cepstral peak prominence and EGG contact quotient showed an increase among dysphonic participants with SOVM. L1-L0 showed an increase for all participants in SOVM condition (dysphonic and normal). Self-perceived resonant voice quality showed an increase for both groups in SOVM condition. Glottal airflow showed a decrease for the dysphonic participants in SOVM condition. Phonation threshold pressure and subglottic pressure showed a decrease for both groups in SOVM condition.

Conclusion

The present study suggests that immediate positive effect could be produced by connected speech phonatory tasks using the SOVM in both dysphonic subjects and subjects with normal voice, the change being greater among the former. SOVM seems to promote an easy voice production and a more efficient phonation.

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Diagnostic Accuracy of CT for Prediction of Bladder Cancer Treatment Response with and without Computerized Decision Support

Publication date: Available online 10 November 2018

Source: Academic Radiology

Author(s): Kenny H. Cha, Lubomir M. Hadjiiski, PhD, Richard H. Cohan, MD, Heang-Ping Chan, PhD, Elaine M. Caoili, MD, Matthew Davenport, MD, Ravi K. Samala, PhD, Alon Z. Weizer, MD, Ajjai Alva, MD, Galina Kirova-Nedyalkova, MD, PhD, Kimberly Shampain, MD, Nathaniel Meyer, MD, Daniel Barkmeier, MD, PhD, Sean Woolen, MD, Prasad R. Shankar, MD, Isaac R. Francis, MD, Phillip Palmbos, MD

Rationale and Objectives

To evaluate whether a computed tomography (CT)-based computerized decision-support system for muscle-invasive bladder cancer treatment response assessment (CDSS-T) can improve identification of patients who have responded completely to neoadjuvant chemotherapy.

Materials and Methods

Following Institutional Review Board approval, pre-chemotherapy and post-chemotherapy CT scans of 123 subjects with 157 muscle-invasive bladder cancer foci were collected retrospectively. CT data were analyzed with a CDSS-T that uses a combination of deep-learning convolutional neural network and radiomic features to distinguish muscle-invasive bladder cancers that have fully responded to neoadjuvant treatment from those that have not. Leave-one-case-out cross-validation was used to minimize overfitting. Five attending abdominal radiologists, four diagnostic radiology residents, two attending oncologists, and one attending urologist estimated the likelihood of pathologic T0 disease (complete response) by viewing paired pre/post-treatment CT scans placed side-by-side on an internally-developed graphical user interface. The observers provided an estimate without use of CDSS-T and then were permitted to revise their estimate after a CDSS-T-derived likelihood score was displayed. Observer estimates were analyzed with multi-reader, multi-case receiver operating characteristic methodology. The area under the curve (AUC) and the statistical significance of the difference were estimated.

Results

The mean AUCs for assessment of pathologic T0 disease were 0.80 for CDSS-T alone, 0.74 for physicians not using CDSS-T, and 0.77 for physicians using CDSS-T. The increase in the physicians' performance was statistically significant (P < .05).

Conclusion

CDSS-T improves physician performance for identifying complete response of muscle-invasive bladder cancer to neoadjuvant chemotherapy.

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Texture Analysis Based on Preoperative Magnetic Resonance Imaging (MRI) and Conventional MRI Features for Predicting the Early Recurrence of Single Hepatocellular Carcinoma after Hepatectomy

Publication date: Available online 10 November 2018

Source: Academic Radiology

Author(s): Jing Zhang, Xinjie Liu, Haiping Zhang, Xiaojing He, Yangyang Liu, Jun Zhou, Dajing Guo

Rationale and Objectives

To investigate the value of texture analysis and conventional magnetic resonance imaging (MRI) features for predicting the early recurrence (ER) of single hepatocellular carcinoma (HCC) after hepatectomy.

Materials and Methods

A total of 100 HCC patients were first divided into group A (tumor diameter ≤3 cm) and group B (tumor diameter >3 cm) and then classified into two subgroups with ER or nonearly recurrence. Textural parameters (skewness, kurtosis, uniformity, energy, entropy, and correlation) based on MR images and conventional MRI features were compared between the ER and nonearly recurrence subgroups. Predictive factors for ER were further assessed with multivariate logistic regression analysis. Receiver operating characteristic curve was performed to assess the predictive power.

Results

There were 53 patients in group A and 47 patients in group B. On arterial phase analysis, tumors with ER displayed significantly lower uniformity and higher entropy in group A, and higher skewness and entropy in group B. On portal venous phase analysis, tumors with ER had significantly lower kurtosis and energy in group A, and higher entropy in group B. Irregular margin in groups A and B, and arterial peritumoral enhancement and capsule presence in group B were associated with ER. In multivariate logistic regression analysis, uniformity and entropy based on arterial phase images and irregular margin in group A, and skewness and entropy based on arterial phase images and arterial peritumoral enhancement in group B were independent predictors for ER. Entropy displayed higher predictive power for ER.

Conclusion

Texture analysis based on preoperative MRI are potential quantitative predictors of ER in HCC patients after hepatectomy, and may provide more information for preoperative treatment decision-making and follow up.

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Disease Quantification on PET/CT Images without Explicit Object Delineation

Publication date: Available online 10 November 2018

Source: Medical Image Analysis

Author(s): Yubing Tong, Jayaram K. Udupa, Dewey Odhner, Caiyun Wu, Stephen J. Schuster, Drew A. Torigian

Abstract

Purpose

The derivation of quantitative information from images in a clinically practical way continues to face a major hurdle because of image segmentation challenges. This paper presents a novel approach, called automatic anatomy recognition-disease quantification (AAR-DQ), for disease quantification (DQ) on positron emission tomography/computed tomography (PET/CT) images. This approach explores how to decouple DQ methods from explicit dependence on object (e.g., organ) delineation through the use of only object recognition results from our recently developed automatic anatomy recognition (AAR) method to quantify disease burden.

Method

The AAR-DQ process starts off with the AAR approach for modeling anatomy and automatically recognizing objects on low-dose CT images of PET/CT acquisitions. It incorporates novel aspects of model building that relate to finding an optimal disease map for each organ. The parameters of the disease map are estimated from a set of training image data sets including normal subjects and patients with metastatic cancer. The result of recognition for an object on a patient image is the location of a fuzzy model for the object which is optimally adjusted for the image. The model is used as a fuzzy mask on the PET image for estimating a fuzzy disease map for the specific patient and subsequently for quantifying disease based on this map. This process handles blur arising in PET images from partial volume effect entirely through accurate fuzzy mapping to account for heterogeneity and gradation of disease content at the voxel level without explicitly performing correction for the partial volume effect. Disease quantification is performed from the fuzzy disease map in terms of total lesion glycolysis (TLG) and standardized uptake value (SUV) statistics. We also demonstrate that the method of disease quantification is applicable even when the "object" of interest is recognized manually with a simple and quick action such as interactively specifying a 3D box ROI. Depending on the degree of automaticity for object and lesion recognition on PET/CT, DQ can be performed at the object level either semi-automatically (DQ-MO) or automatically (DQ-AO), or at the lesion level either semi-automatically (DQ-ML) or automatically.

Results

We utilized 67 data sets in total: 16 normal data sets used for model building, and 20 phantom data sets plus 31 patient data sets (with various types of metastatic cancer) used for testing the three methods DQ-AO, DQ-MO, and DQ-ML. The parameters of the disease map were estimated using the leave-one-out strategy. The organs of focus were left and right lungs and liver, and the disease quantities measured were TLG, SUV_Mean, and SUV_Max. On phantom data sets, overall error for the three parameters were approximately 6%, 3%, and 0%, respectively, with TLG error varying from 2% for large "lesions" (37 mm diameter) to 37% for small "lesions" (10 mm diameter). On patient data sets, for non-conspicuous lesions, those overall errors were approximately 19%, 14% and 0%; for conspicuous lesions, these overall errors were approximately 9%, 7%, 0%, respectively, with errors in estimation being generally smaller for liver than for lungs, although without statistical significance.

Conclusions

Accurate disease quantification on PET/CT images without performing explicit delineation of lesions is feasible following object recognition. Method DQ-MO generally yields more accurate results than DQ-AO although the difference is statistically not significant. Compared to current methods from the literature, almost all of which focus only on lesion-level DQ and not organ-level DQ, our results were comparable for large lesions and were superior for smaller lesions, with less demand on training data and computational resources. DQ-AO and even DQ-MO seem to have the potential for quantifying disease burden body-wide routinely via the AAR-DQ approach.

Graphic Abstract

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Assessing the osteogenic potential of zirconia and titanium surfaces with an advanced in vitro model

Publication date: Available online 10 November 2018

Source: Dental Materials

Author(s): Markus Rottmar, Eike Müller, Stefanie Guimond-Lischer, Marc Stephan, Simon Berner, Katharina Maniura-Weber

Abstract

Objectives

In recent years, zirconia dental implants have gained increased attention especially for patients with thin gingival biotypes or patients seeking metal-free restoration. While physical and chemical material surface properties govern the blood-material interaction and subsequent osseointegration processes, the organizational principles underlying the interplay of biochemical and biophysical cues are still not well understood. Therefore, this study investigated how the interaction of a microstructured zirconia surface with blood influences its osseointegration potential compared to microstructured titanium with or without additional nanostructures.

Methods

Microstructured zirconia and micro- (and nano)structured titanium surfaces were fabricated via sandblasting followed by acid etching and their topographical as well as physico-chemical features were thoroughly characterized. Following, an advanced in vitro approach mimicking the initial blood interaction of material surfaces upon implantation was applied. Fibrinogen adsorption, human blood coagulation as well as their influence on cell fate decisions of primary human bone and progenitor cells (HBC) were studied.

Results

Obtained surface micro- and nanostructures on titanium surfaces were sharp with rugged peaks whereas zirconia surfaces were less rough with structures being shallower, more round and granular. Compared to titanium surfaces, the zirconia surface showed increased fibrinogen adsorption, higher levels of total accessible fibrinogen γ-chain moieties yielding in increased platelet adhesion and activation and consequently thrombogenicity. Mineralization of HBC on microstructured surfaces was significantly higher on zirconia than on titanium, but was significantly lower compared to titanium surfaces with nanostructures.

Significance

This study provides insights into blood-material interaction and subsequent cellular events that are important for implant surface development.

Graphical abstract

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Calcium phosphate coatings elaborated by the soaking process on titanium dental implants: Surface preparation, processing and physical–chemical characterization

Publication date: Available online 10 November 2018

Source: Dental Materials

Author(s): Camille Pierre, Ghislaine Bertrand, Christian Rey, Olivier Benhamou, Christèle Combes

Abstract

Objective

Dental implant manufacturers are looking for new surfaces to improve osseointegration. It is accepted that calcium phosphate coatings favor bone healing. Among all the techniques, the soaking process seems attractive because of its ability in producing a bioactive coating at low temperature. The objective of this study is to improve the titanium implant surface roughness and chemistry by optimizing the surface preparation and the soaking process parameters to produce a bioactive and adherent calcium phosphate coating.

Methods

Titanium samples were sandblasted and acid etched. Coatings were realized by an alternate soaking process including a centrifugation step to create a phosphate solution thin film on the implant that reacts with the calcium of the second bath. We performed a characterization of the sample surface with complementary physical and physico-chemical techniques to assess the effect of surface preparation and coating process operating parameters on coating formation and characteristics.

Results

Surface preparation led to a roughness around 1.6 μm, micro-porosities, high surface wettability and removed the embedded sandblasting particles. We showed that the centrifugation step is critical and determines the coating formation, coverage and thickness. A thin coating (∼2 μm) composed of apatite analogous to bone mineral was deposited. The coating adhesion was demonstrated by screwing/unscrewing test in an artificial jawbone.

Significance

The titanium dental implant pre-treatment and coating developed in this study is expected to favor early implant osseointegration through coating dissolution in vivo and could be associated with biological active agents to confer additional functionality to the coating.

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Control freaks: Towards optimal selection of control conditions for fMRI neurofeedback studies

Publication date: Available online 10 November 2018

Source: NeuroImage

Author(s): Bettina Sorger, Frank Scharnowski, David E.J. Linden, Michelle Hampson, Kymberly D. Young

Abstract

fMRI Neurofeedback research employs many different control conditions. Currently, there is no consensus as to which control condition is best, and the answer depends on what aspects of the neurofeedback-training design one is trying to control for. These aspects can range from determining whether participants can learn to control brain activity via neurofeedback to determining whether there are clinically significant effects of the neurofeedback intervention. Lack of consensus over criteria for control conditions has hampered the design and interpretation of studies employing neurofeedback protocols. This paper presents an overview of the most commonly employed control conditions currently used in neurofeedback studies and discusses their advantages and disadvantages. Control conditions covered include no control, treatment-as-usual, bidirectional-regulation control, feedback of an alternative brain signal, sham feedback, and mental-rehearsal control. We conclude that the selection of the control condition(s) should be determined by the specific research goal of the study and best procedures that effectively control for relevant confounding factors.

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Modeling of dynamic cerebrovascular reactivity to spontaneous and externally induced CO2 fluctuations in the human brain using BOLD-fMRI

Publication date: Available online 10 November 2018

Source: NeuroImage

Author(s): Prokopis C. Prokopiou, Kyle T.S. Pattinson, Richard G. Wise, Georgios D. Mitsis

Abstract

In this work, we investigate the regional characteristics of the dynamic interactions between arterial CO₂ and BOLD (dynamic cerebrovascular reactivity - dCVR) during normal breathing and hypercapnic, externally induced step CO₂ challenges. To obtain dCVR curves at each voxel, we use a custom set of basis functions based on the Laguerre and gamma basis sets. This allows us to obtain robust dCVR estimates both in larger regions of interest (ROIs), as well as in individual voxels. We also implement classification schemes to identify brain regions with similar dCVR characteristics. Our results reveal considerable variability of dCVR across different brain regions, as well as during different experimental conditions (normal breathing and hypercapnic challenges), suggesting a differential response of cerebral vasculature to spontaneous CO₂ fluctuations and larger, externally induced CO₂ changes that are possibly associated with the underlying differences in mean arterial CO₂ levels. The clustering results suggest that anatomically distinct brain regions are characterized by different dCVR curves that in some cases do not exhibit the standard, positive valued curves that have been previously reported. They also reveal a consistent set of dCVR cluster shapes for resting and forcing conditions, which exhibit different distribution patterns across brain voxels.

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Human or not human? Performance monitoring ERPs during human agent and machine supervision

Publication date: Available online 10 November 2018

Source: NeuroImage

Author(s): Bertille Somon, Aurélie Campagne, Arnaud Delorme, Bruno Berberian

Abstract

Performance monitoring is a critical process which allows us to both learn from our own errors, and also interact with other human beings. However, our increasingly automated world requires us to interact more and more with automated systems, especially in risky environments. The present EEG study aimed at investigating and comparing the neuro-functional correlates associated with performance monitoring of an automated system and a human agent using a vertically-oriented arrowhead version of the flanker task. Given the influence of task difficulty on performance monitoring, two levels of difficulty were considered in order to assess their impact on supervision activity. A large N2P3 complex in fronto-central regions was observed for both human agent error detection and system error detection during supervision. Using a cluster-based permutation analysis, a significantly decreased P3-like component was found for system compared to human agent error detection. This variation is in line with various psychosocial behavioral studies showing a difference between human-human and human-machine interactions, even though it was not clearly anticipated. Finally, the activity observed during error detection was significantly reduced in the difficult condition compared to the easy one, for both system and human agent supervision. Overall, this study is a first step towards the characterization of the neurophysiological correlates underlying system supervision, and a better understanding of their evolution in more complex environments. To go further, these results need to be replicated in other experiments with various paradigms to assess the robustness of the pattern and decrease during system supervision.

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Prognostic significance of bone morphogenetic protein 6 (BMP6) expression, clinical and pathological factors in clinically node-negative oral squamous cell carcinoma (OSCC)

Publication date: Available online 10 November 2018

Source: Journal of Cranio-Maxillofacial Surgery

Author(s): Petar Suton, Ante Bolanca, Lovorka Grgurevic, Igor Erjavec, Iva Nikles, Danko Muller, Spomenka Manojlovic, Slobodan Vukicevic, Mladen Petrovecki, Stjepan Dokuzovic, Ivica Luksic

Summary

Bone morphogenetic protein 6 (BMP6) has unique properties regarding structure and function in supporting bone formation during development and adult life. Despite its known role in various malignant tumors, the prognostic significance of BMP6 expression in oral squamous cell carcinoma (OSCC) remains unknown. The aim of the study was to investigate immunohistochemical expression of BMP6 in OSCC in correlation with clinical and pathological parameters, disease recurrence and survival. In addition, we investigated other parameters in order to identify prognosticators of neck metastases and final outcome. The study included 120 patients with clinically T1-3N0 OSCC who were primarily surgically treated between 2003 and 2008. There were 99 (82.5%) male and 21 (17.5%) female patients. The five-year disease-specific survival for the whole cohort was 79.7%. Tumors smaller than 2 cm in diameter showed higher incidence of strong BMP6 expression. No statistical correlation was observed between other clinico-pathological factors and BMP6 expression. Expression of BMP6 was not associated with disease recurrence and survival. BMP6 may not serve as prognosticator of final outcome or recurrence in clinically node-negative OSCC subjects. In multivariate analysis predictors of poorer survival were positive surgical margin, moderate tumor cell differentiation and pathological involvement of levels IV and/or V.

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The feasibility of rib grafts in long span mandibular defects reconstruction: a long term follow up

Publication date: Available online 10 November 2018

Source: Journal of Cranio-Maxillofacial Surgery

Author(s): Ahmed M.A. Habib, Shady A. Hassan

Abstract

Aims

To evaluate the efficiency of reconstruction of long span mandibular defects using split rib bundle bone graft.

Materials and methods

Six hundred patients with long span mandibular defects (more than 6 cm long), following resection of aggressive mandibular tumours, were reconstructed with split rib bundle bone graft technique. Immediate reconstruction was performed in all patients. A reconstruction plate was used to support the graft. Two ribs were harvested from the right side of the chest, split into four halves and used to restore the continuity of the mandible. The inclusion criterion was post-surgical mandibular bony defects without soft tissue deficiency. Defects with a history of previous or need of future irradiation were excluded.

Results

The appearance of the patients was accepted in 550 patients. Functional reconstruction was done in 320 patients by osseointegrated dental implants (after 15 months), and removable prosthesis in 150 patients. Infection was minor in 31 patients, moderate in 47 patients and severe in 42 patients. Partial loss of graft, up to 25%, due to moderate infection was reported. Total or near total loss of graft due to severe infection was corrected by reoperation six months later.

Conclusions

This technique is simple, safe, and can be effectively used to reconstruct long-span mandibular defects with minimal complications in selected patients.

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Recovery Pattern following Bimaxillary Orthognathic Surgery: Differences between Sexes

Publication date: Available online 10 November 2018

Source: Journal of Cranio-Maxillofacial Surgery

Author(s): In-Seok Song, Jimi Choi, Un-Bong Baik, Jae-Jun Ryu, Jong-Woo Lim, Young-Jun Choi, Ui-Lyong Lee

Abstract

The investigators hypothesized there would be differences between the sexes in recovery pattern following bimaxillary orthognathic surgery as measured by patient responses at 5 weeks postprocedure. A total of 378 participants underwent bimaxillary orthognathic surgery with or without adjunctive procedures. Participants received questionnaires 5 weeks postsurgery when they visited the outpatient clinic. The questionnaires include variances in surgical factors by sex, and postoperative symptoms which were most difficult to tolerate experiences by sex, respectively. Females were more likely to undergo malarplasty (zygoma reduction) than were male participants (P = <.001), and they required larger maxillary setback than did male participants (P = .003). Malarplasty was significantly correlated with ear fullness in total and female participants (p-value .018, .016, respectively). Snoring is significantly associated with malarplasty and segment osteotomy procedure without gender predominance (p-value= .026, .028, respectively). Over half of participants complained of nasal congestion (55.6%), followed by swelling (29.3%), pain (15.4%), breathing difficulty (10.6%). In conclusion, males and females showed different patterns of postoperative recovery following bimaxillary orthognathic surgery.

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A simple method to estimate the linear length of the orbital floor in complex orbital surgery

Publication date: Available online 9 November 2018

Source: Journal of Cranio-Maxillofacial Surgery

Author(s): Konstantinos Natsis, Maria Piagkou, Ioannis Chryssanthou, Georgios P. Skandalakis, Georgios Tsakotos, Giannoulis Piagkos, Constantinus Politis

Abstract

Background

The orbital floor (OrF) and infraorbital rim (IOR) repair in cases of complete destruction is challenging mainly due to the fact that the defect length cannot be measured. The aim of the current study is to develop a method of calculating the Orf length by using the gender and the lengths of the medial, superior and lateral orbital walls (OrW) of the same orbit.

Material and methods

Ninety-seven (59 male and 38 female) European adult dry skulls were classified according to age: 20-39, 40-59 and 60 years and above. The length of each OrW was measured by using the direct distance between the optic foramen and a landmark in each orbital rim.

Results

A side asymmetry was detected for the lengths of the inferior, superior and medial OrW. Although a gender dimorphism was detected, no correlation with the age was found. Using the Stepwise multiple regression analysis two formulas were developed, one for the right and one for the left OrF with coefficient of determination R² 0.43 and 0.57, respectively.

Conclusions

The proposed formulas represent a simple, applicable and individualized method to calculate the OrF linear length in cases of complete destruction of the IOR and OrF, with accuracy and without the use of expertise material. Such data may improve the surgery planning of orbital floor fractures and complex orbital reconstructions.

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