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Background: Computed tomography (CT) has an underutilized potential for evaluating body composition in clinical settings. Often conducted with intravenous contrast (IVC), CT scans yield unused body composition data due to unclear effects on skeletal muscle area (SMA), skeletal muscle index (SMI), and muscle density (SMD)., Objectives: This study investigates whether weight-adjusted IVC influences SMA, SMI, and SMD differently in females and males compared with noncontrast abdominal CT. In addition, the study explores associations between contrast and noncontrast-assessed SMA, SMI, SMD, and demographic factors., Methods: A comparative observational retrospective study was conducted on Danish patients who underwent consecutive 4-phased contrast-enhanced abdominal CT scans (noncontrast, arterial, venous, and late venous phases). Muscle measures were evaluated using validated semiautomated threshold-based software by 3 independent raters., Results: The study included 72 patients (51 males and 21 females) with a mean age of 59 (55 and 62) y. Weight-adjusted IVC increased SMA by ≤3.28 cm 2 (95% confidence interval [CI]: 2.58, 3.98) corresponding to 2.4% (1.8, 2.9) in the late venous phase compared with noncontrast CT. Analysis between sexes showed no difference in the effects of IVC on SMA and SMI between females and males. However, females exhibited a higher increase in SMD during the venous by a mean of 1.7 HU (0.9; 2.5) and late venous phases with a mean HU of 1.80 (1.0; 2.6) compared with males. Multivariate regression analysis indicated an association between the differences in SMD and sex during venous (-1.38, 95% CI: -2.48, -0.48) and late venous phases (-1.23, 95% CI: -2.27, -0.19)., Conclusions: Weight-adjusted IVC leads to increased SMA, SMI, and SMD. Although SMA and SMI differences were consistent across the sexes, females exhibited a significantly higher SMD increase than males in the venous and late venous phases. Further investigations are necessary to determine the applicability of SMD as a muscle quality proxy in IVC CT scans., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Understanding ethnic variations in body composition is crucial for assessing health risks. Universal models may not suit all ethnicities, and there is limited data on the Inuit population. This study aimed to compare body composition between Inuit and European adults using computed tomography (CT) scans and to investigate the influence of demographics on these measurements. A retrospective analysis was conducted on 50 adults (29 Inuit and 21 European) who underwent standard trauma CT scans. Measurements focused on skeletal muscle index (SMI), various fat indices, and densities at the third lumbar vertebra level, analyzed using the Wilcoxon-Mann-Whitney test and multiple linear regression. Inuit women showed larger fat tissue indices and lower muscle and fat densities than European women. Differences in men were less pronouncehd, with only Intramuscular fat density being lower among Inuit men. Regression indicated that SMI was higher among men, and skeletal muscle density decreased with Inuit ethnicity and age, while visceral fat index was positively associated with age. This study suggests ethnic differences in body composition measures particularly among women, and indicates the need for Inuit-specific body composition models. It higlights the importance of further research into Inuit-specific body composition measurements for better health risk assessment.

Background: Patients with chronic obstructive pulmonary disease (COPD) with low skeletal muscle mass and severe airway obstruction have higher mortality risks. However, the relationship between dynamic/static lung function (LF) and thoracic skeletal muscle measurements (SMM) remains unclear. This study explored patient characteristics (weight, BMI, exacerbations, dynamic/static LF, sex differences in LF and SMM, and the link between LF and SMM changes., Methods: A retrospective analysis of a 12-month prospective follow-up study patients with stable COPD undergoing standardized treatment, covering mild to severe stages, was conducted. The baseline and follow-up assessments included computed tomography and body plethysmography., Results: This study included 35 patients (17 females and 18 males). This study revealed that females had more stable LF but tended to have greater declines in SMM areas and indices than males (-5.4% vs. -1.9%, respectively), despite the fact that females were younger and had higher LF and less exacerbation than males. A multivariate linear regression showed a negative association between the inspiratory capacity/total lung capacity ratio (IC/TLC) and muscle fat area., Conclusions: The findings suggest distinct LF and BC progression patterns between male and female patients with COPD. A low IC/TLC ratio may predict increased muscle fat. Further studies are necessary to understand these relationships better.

Background: Computed tomography (CT) is increasingly used in the clinical workup, and existing scan contains unused body composition data, potentially useful in a clinical setting. However, there is no healthy reference for contrast-enhanced thoracic CT-derived muscle measures. Therefore, we aimed at investigating whether there is a correlation between each of the thoracic and third lumbar vertebra level (L3) skeletal muscle area (SMA), skeletal muscle index (SMI), and skeletal muscle density (SMD) at contrast-enhanced CT in patients without chronic disease., Methods: A proof-of-concept retrospective observational study was based on Caucasian patients without chronic disease, who received CT for trauma between 2012 and 2014. Muscle measures were assessed using a semiautomated threshold-based software by two raters independently. Pearson's correlation between each thoracic level and third lumbar and intraclass correlation between two raters and test-retest with SMA as proxy parameters were used., Results: Twenty-one patients (11 males, 10 females; median age 29 years) were included. The second thoracic vertebra (T2) had the highest median of cumulated SMA (males 314.7 cm 2 , females 118.5 cm 2 ) and SMI (97.8 cm 2 /m 2 and 70.4 cm 2 /m 2 , respectively). The strongest SMA correlation was observed between T5 and L3 (r = 0.970), the SMI between T11 and L3 (r = 0.938), and the SMD between the T10 and L3 (r = 0.890)., Conclusions: This study suggests that any of the thoracic levels can be valid to assess skeletal muscle mass. However, the T5 may be most favourable for measuring SMA, the T11 for SMI, and T10 for SMD when using contrast-enhanced thoracic CT., Relevance Statement: In COPD patients, a CT-derived thoracic muscle mass assessment may help identify who would benefit from focused pulmonary rehabilitation: thoracic contrast-enhanced CT conducted as part of the standard clinical workup can be used for this evaluation., Key Points: • Any thoracic level can be used to assess thoracic muscle mass. • Thoracic level 5 is strongly associated with the 3rd lumbar muscle area. • A strong correlation between the thoracic level 11 and the 3rd lumbar muscle index. • Thoracic level 10 is strongly associated with the 3rd lumbar muscle density., (© 2023. The Author(s).)

Deep learning for the analysis of H&E stains requires a large annotated training set. This may form a labor-intensive task involving highly skilled pathologists. We aimed to optimize and evaluate computer-assisted annotation based on digital dual stains of the same tissue section. H&E stains of primary and metastatic melanoma ( N = 77) were digitized, re-stained with SOX10, and re-scanned. Because images were aligned, annotations of SOX10 image analysis were directly transferred to H&E stains of the training set. Based on 1,221,367 annotated nuclei, a convolutional neural network for calculating tumor burden (CNN TB ) was developed. For primary melanomas, precision of annotation was 100% (95%CI, 99% to 100%) for tumor cells and 99% (95%CI, 98% to 100%) for normal cells. Due to low or missing tumor-cell SOX10 positivity, precision for normal cells was markedly reduced in lymph-node and organ metastases compared with primary melanomas ( p < 0.001). Compared with stereological counts within skin lesions, mean difference in tumor burden was 6% (95%CI, -1% to 13%, p = 0.10) for CNN TB and 16% (95%CI, 4% to 28%, p = 0.02) for pathologists. Conclusively, the technique produced a large annotated H&E training set with high quality within a reasonable timeframe for primary melanomas and subcutaneous metastases. For these lesion types, the training set generated a high-performing CNN TB , which was superior to the routine assessments of pathologists.

Studies have reported sex-based differences in conduit artery function, however little is known about possible sex-based differences in microvascular function, and possible influence of muscle group. Blood-oxygen-level-dependent (BOLD) MR images acquired during ischemia-reperfusion assess the reactive hyperemic response in the microvasculature of skeletal muscle. We tested the hypothesis that women have greater microvascular reactivity, reflected by faster time-to-peak (TTP) and time-to-half-peak (TTHP) of the BOLD response, across all lower leg muscles. In healthy, young men (n = 18) and women (n = 12), BOLD images of both lower legs were acquired continuously during 30 s of rest, 5 min of cuff occlusion and 2 min of reperfusion, in a 3 T MR scanner. Segmentation of tibialis anterior (TA), soleus (SO), gastrocnemius medial (GM), and the peroneal group (PG) were performed using image registration, and TTP and TTHP of the BOLD response were determined for each muscle. Overall, women had faster TTP (p = 0.001) and TTHP (p = 0.01) than men. Specifically, women had shorter TTP and TTHP in TA (27.5-28.4%), PG (33.9-41.6%), SO (14.7-19.7%) and GM (15.4-18.8%). Overall, TTP and TTHP were shorter in TA compared with PG (25.1-31.1%; p ≤ 0.007), SO (14.3-16%; p ≤ 0.03) and GM (15.6-26%; p ≤ 0.01). Intra class correlations analyses showed large variation in absolute agreement (range: 0.10-0.81) of BOLD parameters between legs (within distinct muscles). Faster TTP and TTHP across all lower leg muscles, in women, provide novel evidence of sex-based differences in microvascular function of young adults matched for age, body mass index, and physical activity level., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: In clinical diagnosis, the maximum motion of a cervical joint is thought to be found at the joint's end-range and it is this perception that forms the basis for the interpretation of flexion/extension imaging studies. There have however, been representative cases of joints producing their maximum motion before end-range, but this phenomenon is yet to be quantified., Purpose: To provide a quantitative assessment of the difference between maximum joint motion and joint end-range in healthy subjects. Secondarily to classify joints into type based on their motion and to assess the proportions of these joint types., Study Design: This is an observational study., Subject Sample: Thirty-three healthy subjects participated in the study., Outcome Measures: Maximum motion, end-range motion and surplus motion (the difference between maximum motion and end-range) in degrees were extracted from each cervical joint., Methods: Thirty-three subjects performed one flexion and one extension motion excursion under video fluoroscopy. The motion excursions were divided into 10% epochs, from which maximum motion, end-range and surplus motion were extracted. Surplus motion was then assessed in quartiles and joints were classified into type according to end-range., Results: For flexion 48.9% and for extension 47.2% of joints produced maximum motion before joint end-range (type S). For flexion 45.9% and for extension 46.8% of joints produced maximum motion at joint end-range (type C). For flexion 5.2% of joints and for extension 6.1% of joints concluded their motion anti-directionally (type A). Significant differences were found for C2/C3 (P = 0.000), C3/C4 (P = 0.001) and C4/C5 (P = 0.005) in flexion and C1/C2 (P = 0.004), C3/C4 (P = 0.013) and C6/C7 (P = 0.013) in extension when comparing the joint end- range of type C and type S. The average pro-directional (motion in the direction of neck motion) surplus motion was 2.41° ± 2.12° with a range of (0.07° -14.23°) for flexion and 2.02° ± 1.70° with a range of (0.04°-6.97°) for extension., Conclusion: This is the first study to categorise joints by type of motion. It cannot be assumed that end-range is a demonstration of a joint's maximum motion, as type S constituted approximately half of the joints analysed in this study.

Purpose: This feasibility and validation study addresses the potential use of magnetic resonance imaging (MRI) texture analysis of the pancreas in patients with chronic pancreatitis (CP)., Methods: Extraction of 851 MRI texture features from diffusion weighted imaging (DWI) of the pancreas was performed in 77 CP patients and 22 healthy controls. Features were reduced to classify patients into subgroups, and a Bayes classifier was trained using a tenfold cross-validation forward selection procedure. The classifier was optimized to obtain the best average m-fold accuracy, sensitivity, specificity, and positive predictive value. Classifiers were: presence of disease (CP vs. healthy controls), etiological risk factors (alcoholic vs. nonalcoholic etiology of CP and tobacco use vs. no tobacco use), and complications to CP (presumed pancreatogenic diabetes vs. no diabetes and pancreatic exocrine insufficiency vs. normal pancreatic function)., Results: The best classification performance was obtained for the disease classifier selecting only five of the original features with 98% accuracy, 97% sensitivity, 100% specificity, and 100% positive predictive value. The risk factor classifiers obtained good performance using 9 (alcohol: 88% accuracy) and 10 features (tobacco: 86% accuracy). The two complication classifiers obtained similar accuracies with only 4 (diabetes: 83% accuracy) and 3 features (exocrine pancreatic function: 82% accuracy)., Conclusion: Pancreatic texture analysis demonstrated to be feasible in patients with CP and discriminate clinically relevant subgroups based on etiological risk factors and complications. In future studies, the method may provide useful information on disease progression (monitoring) and detection of biomarkers characterizing early-stage CP.

Background: Opioids are known to affect gastrointestinal motility, but their effect on fluid absorption and secretion is poorly understood in humans., Purpose: To investigate the effect of oxycodone on colonic fecal volume and stool dryness by using a novel MRI-based technique., Study Type: Prospective, randomized, double-blinded, crossover study., Subjects: Twenty-five healthy male volunteers (median age: 24 years [range: 21-56]; mean body mass index [BMI]: 23.9 kg/m 2 [range: 22.9-25.0]) without known gastrointestinal disease., Field Strength/sequence: T 2 -weighted and two-point Dixon MRI scans of the abdomen at 1.5 T., Assessment: Subjects were treated for 5 days with prolonged-release oxycodone or a placebo. Imaging was performed on the first and last study day in each period. Images of the colon were analyzed with semiautomatic k-means-based segmentation software. Regional colonic fecal volumes were quantified excluding gas volume and colon wall. Two-point Dixon and T 2 -weighted MRI signal intensity were assessed as a proxy of colonic stool dryness. Data were obtained in a previously reported study., Statistical Tests: Intraclass correlation coefficients were used to test the reliability of measurements between days, while repeated measures mixed models were applied to test treatment effects., Results: After oxycodone treatment, total colonic fecal volume was significantly increased compared with placebo (mean change 100 mL vs. -13 mL; P = 0.001), with the largest increase (24%) observed in the ascending colon/cecum (P = 0.001). Dixon signal increased (less water in colon content) after oxycodone treatment compared with placebo (mean 0.09 vs. -0.02; P < 0.001). T 2 -weighted signal decreased (less water in colon content) after oxycodone treatment compared with placebo (mean -0.03 vs. 0.03; P = 0.002)., Data Conclusion: The 5-day oxycodone treatment increased colonic fecal volume and increased stool dryness compared with placebo. This imaging-based method for noninvasive analysis of colon content has the potential to characterize gastrointestinal symptoms in general, such as in constipation., Level of Evidence: 2 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019;50:733-745., (© 2019 International Society for Magnetic Resonance in Medicine.)

Quantitative susceptibility mapping (QSM) is based on magnetic resonance imaging (MRI) phase measurements and has gained broad interest because it yields relevant information on biological tissue properties, predominantly myelin, iron and calcium in vivo. Thereby, QSM can also reveal pathological changes of these key components in widespread diseases such as Parkinson's disease, Multiple Sclerosis, or hepatic iron overload. While the ill-posed field-to-source-inversion problem underlying QSM is conventionally assessed by the means of regularization techniques, we trained a fully convolutional deep neural network - DeepQSM - to directly invert the magnetic dipole kernel convolution. DeepQSM learned the physical forward problem using purely synthetic data and is capable of solving the ill-posed field-to-source inversion on in vivo MRI phase data. The magnetic susceptibility maps reconstructed by DeepQSM enable identification of deep brain substructures and provide information on their respective magnetic tissue properties. In summary, DeepQSM can invert the magnetic dipole kernel convolution and delivers robust solutions to this ill-posed problem., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Quantitative susceptibility mapping (QSM) reveals pathological changes in widespread diseases such as Parkinson's disease, Multiple Sclerosis, or hepatic iron overload. QSM requires multiple processing steps after the acquisition of magnetic resonance imaging (MRI) phase measurements such as unwrapping, background field removal and the solution of an ill-posed field-to-source-inversion. Current techniques utilize iterative optimization procedures to solve the inversion and background field correction, which are computationally expensive and lead to suboptimal or over-regularized solutions requiring a careful choice of parameters that make a clinical application of QSM challenging. We have previously demonstrated that a deep convolutional neural network can invert the magnetic dipole kernel with a very efficient feed forward multiplication not requiring iterative optimization or the choice of regularization parameters. In this work, we extended this approach to remove background fields in QSM. The prototype method, called SHARQnet, was trained on simulated background fields and tested on 3T and 7T brain datasets. We show that SHARQnet outperforms current background field removal procedures and generalizes to a wide range of input data without requiring any parameter adjustments. In summary, we demonstrate that the solution of ill-posed problems in QSM can be achieved by learning the underlying physics causing the artifacts and removing them in an efficient and reliable manner and thereby will help to bring QSM towards clinical applications., (Copyright © 2019. Published by Elsevier GmbH.)

Breast cancer is the most frequent cancer among women worldwide. Ki67 can be used as an immunohistochemical pseudo marker for cell proliferation to determine how aggressive the cancer is and thereby the treatment of the patient. No standard Ki67 staining protocol exists, resulting in inter-laboratory stain variability. Therefore, it is important to determine the quality control of a staining protocol to ensure correct diagnosis and treatment of patients. Currently, quality control is performed by the organization NordiQC that use an expert panel-based qualitative assessment system. However, no objective method exists to determine the quality of a staining protocol. In this study, we propose an algorithm, to objectively assess staining quality from segmented cell nuclei structures extracted from cell lines. The cell nuclei were classified into either Ki67 positive or negative to determine the Ki67 proliferation index within the cell lines. A Ki67 stain quality model based on ordinal logistic regression was developed to determine the quality of a staining protocol from features extracted from the segmented cell nuclei in the cell lines. The algorithm was able to segment and classify Ki67 positive cell nuclei with a sensitivity and positive predictive value (PPV) of 0.90 and 0.94 and Ki67 negative cell nuclei with a sensitivity and PPV of 0.78 and 0.78. The mean difference between a manual and automatic Ki67 proliferation index was -0.003 with a standard deviation of 0.056. The ordinal logistic regression model found that the stain intensity for both the Ki67 positive and Ki67 negative cell nuclei were statistically significant as parameters determining the stain quality from the cell line cores. The framework shows great promise for using cell nuclei information from cell lines to predict the staining quality of staining protocols. © 2018 International Society for Advancement of Cytometry., (© 2018 International Society for Advancement of Cytometry.)

Purpose: To automatically assess the aggressiveness of prostate cancer (PCa) lesions using zonal-specific image features extracted from diffusion weighted imaging (DWI) and T2W MRI., Methods: Region of interest was extracted from DWI (peripheral zone) and T2W MRI (transitional zone and anterior fibromuscular stroma) around the center of 112 PCa lesions from 99 patients. Image histogram and texture features, 38 in total, were used together with a k-nearest neighbor classifier to classify lesions into their respective prognostic Grade Group (GG) (proposed by the International Society of Urological Pathology 2014 consensus conference). A semi-exhaustive feature search was performed (1-6 features in each feature set) and validated using threefold stratified cross validation in a one-versus-rest classification setup., Results: Classifying PCa lesions into GGs resulted in AUC of 0.87, 0.88, 0.96, 0.98, and 0.91 for GG1, GG2, GG1 + 2, GG3, and GG4 + 5 for the peripheral zone, respectively. The results for transitional zone and anterior fibromuscular stroma were AUC of 0.85, 0.89, 0.83, 0.94, and 0.86 for GG1, GG2, GG1 + 2, GG3, and GG4 + 5, respectively., Conclusion: This study showed promising results with reasonable AUC values for classification of all GG indicating that zonal-specific imaging features from DWI and T2W MRI can be used to differentiate between PCa lesions of various aggressiveness., (© 2019 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.)

Zonal segmentation of the prostate gland using magnetic resonance imaging (MRI) is clinically important for prostate cancer (PCa) diagnosis and image-guided treatments. A two-dimensional convolutional neural network (CNN) based on the U-net architecture was evaluated for segmentation of the central gland (CG) and peripheral zone (PZ) using a dataset of 40 patients (34 PCa positive and 6 PCa negative) scanned on two different MRI scanners (1.5T GE and 3T Siemens). Images were cropped around the prostate gland to exclude surrounding tissues, resampled to 0.5 × 0.5 × 0.5    mm   voxels and z -score normalized before being propagated through the CNN. Performance was evaluated using the Dice similarity coefficient (DSC) and mean absolute distance (MAD) in a fivefold cross-validation setup. Overall performance showed DSC of 0.794 and 0.692, and MADs of 3.349 and 2.993 for CG and PZ, respectively. Dividing the gland into apex, mid, and base showed higher DSC for the midgland compared to apex and base for both CG and PZ. We found no significant difference in DSC between the two scanners. A larger dataset, preferably with multivendor scanners, is necessary for validation of the proposed algorithm; however, our results are promising and have clinical potential.

Cervical spine motion analysis using videofluoroscopy is currently a technique without a gold standard. We demonstrate the reliability of a rigid and reliable analysis methodology for cervical motion using videofluoroscopic images, representing the entire range of motion during flexion and extension, from the neutral position to the end-range in the sagittal plane. Two researchers with radiography and vertebral marking expertise, and two inexperienced researchers with 10 hours of training manually marked anatomical structures on fluoroscopic images in a procedure designed to control for vertebral rotation around the mid-plane axis. The average marking error across examiners and images was -0.12 ∘ (standard deviation: 0.88°), and the intraexaminer error ranged from -1.00 ∘ to 1.61° (standard deviation range: 0.27°-1.19°). Our method demonstrated lower errors compared to the higher resolution X-ray studies, and proved that vertebral marking can be performed by persons with no experience in radiographic image analysis., (Copyright © 2018 IPEM. Published by Elsevier Ltd. All rights reserved.)

Purpose: A method for automatically quantifying emphysema regions using High-Resolution Computed Tomography (HRCT) scans of patients with chronic obstructive pulmonary disease (COPD) that does not require manually annotated scans for training is presented., Methods: HRCT scans of controls and of COPD patients with diverse disease severity are acquired at two different centers. Textural features from co-occurrence matrices and Gaussian filter banks are used to characterize the lung parenchyma in the scans. Two robust versions of multiple instance learning (MIL) classifiers that can handle weakly labeled data, miSVM and MILES, are investigated. Weak labels give information relative to the emphysema without indicating the location of the lesions. The classifiers are trained with the weak labels extracted from the forced expiratory volume in one minute (FEV1) and diffusing capacity of the lungs for carbon monoxide (DLCO). At test time, the classifiers output a patient label indicating overall COPD diagnosis and local labels indicating the presence of emphysema. The classifier performance is compared with manual annotations made by two radiologists, a classical density based method, and pulmonary function tests (PFTs)., Results: The miSVM classifier performed better than MILES on both patient and emphysema classification. The classifier has a stronger correlation with PFT than the density based method, the percentage of emphysema in the intersection of annotations from both radiologists, and the percentage of emphysema annotated by one of the radiologists. The correlation between the classifier and the PFT is only outperformed by the second radiologist., Conclusions: The presented method uses MIL classifiers to automatically identify emphysema regions in HRCT scans. Furthermore, this approach has been demonstrated to correlate better with DLCO than a classical density based method or a radiologist, which is known to be affected in emphysema. Therefore, it is relevant to facilitate assessment of emphysema and to reduce inter-observer variability., Competing Interests: The authors have declared that no competing interests exist.

In recent years, the ability to accurately measuring and analyzing the morphology of small pulmonary structures on chest CT images, such as airways, is becoming of great interest in the scientific community. As an example, in COPD the smaller conducting airways are the primary site of increased resistance in COPD, while small changes in airway segments can identify early stages of bronchiectasis. To date, different methods have been proposed to measure airway wall thickness and airway lumen, but traditional algorithms are often limited due to resolution and artifacts in the CT image. In this work, we propose a Convolutional Neural Regressor (CNR) to perform cross-sectional measurements of airways, considering wall thickness and airway lumen at once. To train the networks, we developed a generative synthetic model of airways that we refined using a Simulated and Unsupervised Generative Adversarial Network (SimGAN). We evaluated the proposed method by first computing the relative error on a dataset of synthetic images refined with SimGAN, in comparison with other methods. Then, due to the high complexity to create an in-vivo ground-truth, we performed a validation on an airway phantom constructed to have airways of different sizes. Finally, we carried out an indirect validation analyzing the correlation between the percentage of the predicted forced expiratory volume in one second (FEV1%) and the value of the Pi10 parameter. As shown by the results, the proposed approach paves the way for the use of CNNs to precisely and accurately measure small lung airways with high accuracy.

Introduction: Pregnancy complicated by diabetes mellitus (DM) is a central obstetric problem often complicated by fetal macrosomia and increased risk of intrapartum asphyxia. This risk might be explained by fetoplacental vascular abnormalities. This study aimed to investigate the fetoplacental vascular volume by placental CT angiography in normal pregnancies and in pregnancies complicated by type 1 DM (T1DM), diet controlled gestational DM (GDMd), and insulin treated gestational DM (GDMi)., Methods: Postpartum, barium contrast enhanced placental CT angiography was performed in 27 normal pregnancies and 25 DM pregnancies (8 T1DM, 8 GDMd, and 9 GDMi). The fetoplacental vascular volume/placenta weight (FVV/PW)-ratio and fetoplacental vascular volume/birth weight (FVV/BW)-ratio of each diabetic group were compared to the normal group with multiple regression analysis adjusted for GA. In all pregnancies a standardized histopathological placental examination was performed postpartum., Results: In normal pregnancies, the fetoplacental vascular volume increased with GA (p < 0.001), placental weight (p < 0.001), and birth weight (p < 0.001). In T1DM and GDMi pregnancies, the gestational age adjusted placental weight and the birth weight were increased when compared to normal pregnancies (p < 0.05). The FVV/BW-ratio was significantly reduced in both T1DM and GDMi pregnancies when compared to normal pregnancies (p = 0.003 and p = 0.009, respectively)., Discussion: This study demonstrates, that in insulin treated DM pregnancies the fetus as well as the placenta is larger than normal. However, despite a large placenta, a relatively smaller fetoplacental vascular volume supplies the macrosomic fetus. This finding might explain why fetuses from insulin treated DM pregnancies have high vulnerability to intrauterine and intrapartum asphyxia., (Copyright © 2018. Published by Elsevier Ltd.)

Introduction: Current knowledge of the fetoplacental vasculature in fetal growth restriction (FGR) due to placental dysfunction focuses on the microvasculature rather than the macrovasculature. The aim of this study was to investigate the feasibility of computed tomography angiography to analyze the fetoplacental macrovasculature in normal and FGR pregnancies., Material and Methods: We included 29 placentas (22-42 weeks of gestation) from normal birthweight pregnancies and eight placentas (26-37 weeks of gestation) from FGR pregnancies (birthweight < -15% and abnormal umbilical Doppler flow). We performed postpartum placental computed tomography angiography followed by semi-automatic three-dimensional image segmentation., Results: A median of nine (range seven to eleven) vessel generations was identified. In normal birthweight placentas, gestational age was positively linearly correlated with macrovascular volume (p = 0.002), vascular surface area (p < 0.0005) and number of vessel junctions (p = 0.012), but not with vessel diameter and inter-branch length. The FGR placentas had a lower weight (p = 0.004) and smaller convex volume (p = 0.022) (smallest convex volume containing the macrovasculature); however, macrovascular volume was not significantly reduced. Hence, macrovascular density given as macrovascular outcomes per placental volume was increased in FGR placentas: macrovascular volume per convex volume (p = 0.004), vascular surface area per convex volume (p = 0.004) and number of vessel junctions per convex volume (p = 0.037)., Conclusions: Evaluation of the fetoplacental macrovasculature is feasible with computed tomography angiography. In normal birthweight placentas, macrovascular volume and surface area increase as pregnancy advances by vessel branching rather than increased vessel diameter and elongation. The FGR placenta was smaller; however, the macrovascular volume was within normal range because of an increased macrovascular density., (© 2018 Nordic Federation of Societies of Obstetrics and Gynecology.)

Objective: The purpose of this study was to investigate within- and between-day repeatability of free and unrestricted healthy cervical flexion and extension motion when assessing dynamic cervical spine motion., Methods: Fluoroscopy videos of 2 repeated cervical flexion and 2 repeated extension motions were examined for within-day repeatability (20-second interval) for 18 participants (6 females) and between-day repeatability (1-week interval) for 15 participants (6 females). The dynamic cervical motions were free and unrestricted from neutral to end range. The flexion videos and extension videos were evenly divided into 10% epochs of the C0-to-C7 range of motion. Within-day and between-day repeatability of joint motion angles (all 7 joints and epochs, respectively) was tested in a repeated-measures analysis of variance. Joint motion angle differences between repetitions were calculated for each epoch and joint (7 joints), and these joint motion angle differences between within-day and between-day repetitions were tested in mixed-model analysis of variance., Results: For all joints and epochs, respectively, no significant differences were found in joint motion angle between within-day or between-day repetitions. There were no significant effects of joint motion angle differences between within-day and between-day repetitions. The average within-day joint motion angle differences across all joints and epochs were 0.00° ± 2.98° and 0.00° ± 3.05° for flexion and extension, respectively. The average between-day joint motion angle differences were 0.02° ± 2.56° and 0.05° ± 2.40° for flexion and extension, respectively., Conclusions: This is the first study to report the within-day and between-day joint motion angle differences of repeated cervical flexion and extension. This study supports the idea that cervical joints repeat their motion accurately., (Copyright © 2018. Published by Elsevier Inc.)

Currently, diagnosis of colon cancer is based on manual examination of histopathological images by a pathologist. This can be time consuming and interpretation of the images is subject to inter- and intra-observer variability. This may be improved by introducing a computer-aided diagnosis (CAD) system for automatic detection of cancer tissue within whole slide hematoxylin and eosin (H&E) stains. Cancer disrupts the normal control mechanisms of cell proliferation and differentiation, affecting the structure and appearance of the cells. Therefore, extracting features from segmented cell nuclei structures may provide useful information to detect cancer tissue. A framework for automatic classification of regions of interest (ROI) containing either benign or cancerous colon tissue extracted from whole slide H&E stained images using cell nuclei features was proposed. A total of 1,596 ROI's were extracted from 87 whole slide H&E stains (44 benign and 43 cancer). A cell nuclei segmentation algorithm consisting of color deconvolution, k-means clustering, local adaptive thresholding, and cell separation was performed within the ROI's to extract cell nuclei features. From the segmented cell nuclei structures a total of 750 texture and intensity-based features were extracted for classification of the ROI's. The nine most discriminative cell nuclei features were used in a random forest classifier to determine if the ROI's contained benign or cancer tissue. The ROI classification obtained an area under the curve (AUC) of 0.96, sensitivity of 0.88, specificity of 0.92, and accuracy of 0.91 using an optimized threshold. The developed framework showed promising results in using cell nuclei features to classify ROIs into containing benign or cancer tissue in H&E stained tissue samples. © 2017 International Society for Advancement of Cytometry., (© 2017 International Society for Advancement of Cytometry.)

Epicardial ultrasound (EUS) can be used for intra-operative quality assessment of coronary artery bypass anastomoses. To quantify the anastomotic quality from EUS images, the area of anastomotic structures has to be extracted from EUS sequences. Currently, this is done manually as no objective methods are available. We used an automatic anastomosis segmentation algorithm to extract the area of anastomotic structures from in vivo EUS sequences obtained from 16 porcine anastomoses. The algorithm consists of four major components: vessel detection, vessel segmentation, segmentation quality control and inter-frame contour alignment. The segmentation accuracy was assessed using m-fold cross-validation based on 830 manual segmentations of the anastomotic structures. A Dice coefficient of 0.879 (±0.073) and an absolute area difference of 16.95% (±17.94) were obtained. The proposed segmentation algorithm has potential to automatically extract the area of anastomotic structures., (Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

The study describes a novel algorithm for deriving myocardial strain from an entire cardiac cycle using high-frame-rate ultrasound images. Validation of the tracking algorithm was conducted in vitro prior to the application to patient images. High-frame-rate ultrasound images were acquired in vivo from 10 patients, and strain curves were derived in six myocardial regions around the left ventricle from the apical four-chamber view. Strain curves derived from high-frame-rate images had a higher frequency content than those derived using conventional methods, reflecting improved temporal sampling., (Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Background: Recent advancements in medical imaging have resulted in a significant growth in diagnostic possibilities of neurodegenerative disorders. Neuroanatomical abnormalities of the cerebral cortex in Alzheimer's disease (AD), the most frequent type of dementia in the elderly, can be observed in morphology analysis of cortical sulci, and used to distinguish between cognitively normal (CN) subjects and subjects with AD., Objective: The purpose of this paper was to extract sulcal features by means of computing a sulcal medial surface for AD/CN classification., Methods: 24 distinct sulci per subject were extracted from 210 subjects from the ADNI database by the BrainVISA sulcal identification pipeline. Sulcal medial surface features (depth, length, mean and Gaussian curvature, surface area) were computed for AD/CN classification with a support vector machine (SVM)., Results: The obtained 10-fold cross-validated classification accuracy was 87.9%, sensitivity 90.0%, and specificity 86.7%, based on ten features. The area under the receiver operating characteristic curve (AUC) was 0.89., Conclusions: The sulcal medial surface features can be used as biomarkers for cortical neuroanatomical abnormalities in AD. All the features were located in the left hemisphere, which had previously been reported to be more severely affected in AD and to lose grey matter faster than the right hemisphere., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: In Burkina Faso, the government has implemented various health sector reforms in order to overcome financial and geographical barriers to citizens' access to primary healthcare throughout the country. Despite these efforts, morbidity and mortality rates among children remain high and the utilization of public healthcare services low. This study explores the relationship between mothers' intentions to use public health services in cases of child sickness, their social strategies and cultural practices to act on these intentions and the actual services provided at the primary health care facilities. Focusing on mothers as the primary caregivers, we follow their pathways from the onset of symptoms through their various attempts of providing treatment for their sick children. The overall objective is to discuss the interconnectedness of various factors, inside and outside of the primary health care services that contribute to the continuing high child morbidity and mortality rates., Methods: The study is based on ethnographic fieldwork, including in-depth interviews and follow-up interviews with 27 mothers, informal observations of daily-life activities and structured observations of clinical encounters. Data analysis took the form of thematic analysis., Results and Discussion: Focusing on the mothers' social strategies and cultural practices, three forms of responses/actions have been identified: home-treatment, consultation with a traditional specialist, and consultation at the primary health care services. Due to their accumulated vulnerabilities, mothers shift pragmatically from one treatment to another. However, the sporadic nature of their treatment-seeking hinders them in obtaining long-term solutions and the result is recurrent child illnesses and relapses over long periods of time. The routinization of the clinical encounter at rural dispensaries furthermore fails to address these complexities of children's illnesses., Conclusions: The analysis of case studies, interviews and observations shows how mothers in a rural area struggle and often fail to receive care at public healthcare facilities. Health service delivery could be organized in a manner that responds better to the needs of these mothers in terms of both access and retention.

Improving the use of public maternal health facilities to prevent maternal death is a priority in developing countries. Accumulating evidence suggests that a key factor in choosing a facility-based delivery is the collaboration and the communication between healthcare providers and women. This article attempts to provide a fine-grained understanding of health system deficiencies, healthcare provider practices and women's experiences with maternal public healthcare. This article presents findings from ethnographic research conducted in the Central-East Region of Burkina Faso over a period of eight months (January-August 2013). It is based on monthly interviews with 14 women from village (10) and town (4) and on structured observations of clinical encounters in three primary healthcare facilities (two rural and one urban) (23 days). In addition, 13 health workers were interviewed and 11 focus groups with women from village (6) and town (5) were conducted (48 participants). Guided by an analytic focus on strategies and tactics and drawing on recent discussions on the notion of 'biomedical security', the article explores what tactics women employ in their efforts to maximize their chances of having a positive experience with public maternal healthcare. The synthesis of the cases shows that, in a context of poverty and social insecurity, women employ five tactics: establishing good relations with health workers, being mindful of their 'health booklet', attending prenatal care consultations, minimizing the waiting time at the maternity unit and using traditional medicines. In this way, women strive to achieve biomedical security for themselves and their child and to preserve their social reputation. The study reveals difficulty in the collaboration and communication between health workers and women and suggests that greater attention should be paid to social relations between healthcare providers and users., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Segmental distribution of colorectal volume is relevant in a number of diseases, but clinical and experimental use demands robust reliability and validity. Using a novel semi-automatic magnetic resonance imaging-based technique, the aims of this study were to describe: (i) inter-individual and intra-individual variability of segmental colorectal volumes between two observations in healthy subjects and (ii) the change in segmental colorectal volume distribution before and after defecation., Methods: The inter-individual and intra-individual variability of four colorectal volumes (cecum/ascending colon, transverse, descending, and rectosigmoid colon) between two observations (separated by 52 ± 10) days was assessed in 25 healthy males and the effect of defecation on segmental colorectal volumes was studied in another seven healthy males., Key Results: No significant differences between the two observations were detected for any segments (All p > 0.05). Inter-individual variability varied across segments from low correlation in cecum/ascending colon (intra-class correlation coefficient [ICC] = 0.44) to moderate correlation in the descending colon (ICC = 0.61) and high correlation in the transverse (ICC = 0.78), rectosigmoid (ICC = 0.82), and total volume (ICC = 0.85). Overall intra-individual variability was low (coefficient of variance = 9%). After defecation the volume of the rectosigmoid decreased by 44% (p = 0.003). The change in rectosigmoid volume was associated with the true fecal volume (p = 0.02)., Conclusions & Inferences: Imaging of segmental colorectal volume, morphology, and fecal accumulation is advantageous to conventional methods in its low variability, high spatial resolution, and its absence of contrast-enhancing agents and irradiation. Hence, the method is suitable for future clinical and interventional studies and for characterization of defecation physiology., (© 2015 John Wiley & Sons Ltd.)

This article makes a contribution to the debate about health service utilisation and the role of trust in fostering demand for health services in sub-Saharan Africa. It is framed as a narrative literature review based on a thematic analysis of nine empirical, qualitative studies. For the purposes of this article trust is defined as a voluntary course of action, which involves the optimistic expectation that the trustee will do no harm to the trustor and is increasingly perceived as an important influence on health system functioning. The article looks at trust issues in interpersonal, intergroup and institutional situations. The findings of the review point to four elements that are important for trust to develop in health sector relationships: the sensitive use of discretionary power by health workers, perceived empathy by patients of the health workers, the quality of medical care and workplace collegiality. When trust works in health sector encounters, it reduces the social complexity and inherent uneven distribution of power between clients and providers. The article concludes that understanding and supporting trust processes between patients and providers, as well as between co-workers and managers, will improve health sector collaboration and stimulate demand for health care services.

Purpose: To develop a novel semi-automatic segmentation method for quantification of the colon from magnetic resonance imaging (MRI)., Methods: Fourteen abdominal T2-weighted and dual-echo Dixon-type water-only MRI scans were obtained from four healthy subjects. Regions of interest containing the colon were outlined manually on the T2-weighted images. Segmentation of the colon and feces was obtained using k-means clustering and image registration. Regional colonic and fecal volumes were obtained. Inter-observer agreement between two observers was assessed using the Dice similarity coefficient as measure of overlap., Results: Colonic segmentations showed wide variation in volume and morphology between subjects. Colon volumes of the four healthy subjects for both observers were (median [interquartile range]) ascending colon 200 mL [169.5-260], transverse 200.5 mL [113.5-242.5], descending 148 mL [121.5-178.5], sigmoid-rectum 277 mL [192-345], and total 819 mL [687-898.5]. Overlap agreement for the total colon segmentation between the two observers was high with a Dice similarity coefficient of 0.91 [0.84-0.94]. The colon volume to feces volume ratio was on average 0.7., Conclusion: Regional colon volumes were comparable to previous findings using fully manual segmentation. The method showed good agreement between observers and may be used in future studies of gastrointestinal disorders to assess colon and fecal volume and colon morphology. Novel insight into morphology and quantitative assessment of the colon using this method may provide new biomarkers for constipation and abdominal pain compared to radiography which suffers from poor reliability.

Purpose: Epicardial ultrasound (EUS) can be used to assess the quality of coronary artery bypass graft surgery (CABG) anastomoses by determining stenotic rates. Currently, no objective quantitative methods are available for the analysis of EUS images. Therefore, surgeons have to be trained in interpreting EUS images, which may limit the use of EUS in clinical practice. Automatic detection of vessel structures can enable the objective and quantitative quality assessment of anastomoses without user interaction to facilitate the revision of anastomoses during the primary surgery., Methods: An automatic vessel detection algorithm extracted and detected image regions that uniquely intersected with the vessel lumen of anastomotic structures. First, an initial pixel-based segmentation was performed from regional minimums using a watershed segmentation and an adaptive thresholding approach. A region-based merging step was then performed to merge oversegmented vessel structures using a Bayesian classification of different region combinations constructed from the pixel-based segmentations. Finally, a vessel classification step was performed on the extracted regions after the region-based merging to determine the probabilities that the regions contained vessel structures., Results: The performance of the vessel classifier was tested using m-fold cross-validation of 320 EUS images containing anastomotic vessel structures from 16 anastomoses made on healthy porcine vessels. An area under the curve of 0.966 (95 % CI 0.951-0.984) and 0.989 (95 % CI 0.985-0.993, p < 0.001) of a precision-recall and receiver operator characteristic curve, respectively, was obtained when detecting vessel regions extracted from the EUS images., Conclusions: The vessel detection algorithm can detect vessel regions in EUS images at a high accuracy. It can be used to enable the automatic analysis of EUS images for the quality assessment of CABG anastomoses.

Purpose: An automatic method for 3D prostate segmentation in magnetic resonance (MR) images is presented for planning image-guided radiotherapy treatment of prostate cancer., Methods: A spatial prior based on intersubject atlas registration is combined with organ-specific intensity information in a graph cut segmentation framework. The segmentation is tested on 67 axial T2-weighted MR images in a leave-one-out cross validation experiment and compared with both manual reference segmentations and with multiatlas-based segmentations using majority voting atlas fusion. The impact of atlas selection is investigated in both the traditional atlas-based segmentation and the new graph cut method that combines atlas and intensity information in order to improve the segmentation accuracy. Best results were achieved using the method that combines intensity information, shape information, and atlas selection in the graph cut framework., Results: A mean Dice similarity coefficient (DSC) of 0.88 and a mean surface distance (MSD) of 1.45 mm with respect to the manual delineation were achieved., Conclusions: This approaches the interobserver DSC of 0.90 and interobserver MSD 0f 1.15 mm and is comparable to other studies performing prostate segmentation in MR.

Background: Deformable image registrations are prone to errors in aligning reliable anatomically features. Consequently, identification of registration inaccuracies is important. Particularly thoracic three-dimensional (3D) computed tomography (CT)-CT image registration is challenging due to lack of contrast in lung tissue. This study aims for validation of thoracic CT-CT image registration using auto-segmented anatomically landmarks., Material and Methods: Five lymphoma patients were CT scanned three times within a period of 18 months, with the initial CT defined as the reference scan. For each patient the two successive CT scans were registered to the reference CT using three different image registration algorithms (Demons, B-spline and Affine). The image registrations were evaluated using auto-segmented anatomical landmarks (bronchial branch points) and Dice Similarity Coefficients (DSC). Deviation of corresponding bronchial landmarks were used to quantify inaccuracies in respect of both misalignment and geometric location within lungs., Results: The median bronchial branch point deviations were 1.6, 1.1 and 4.2 (mm) for the three tested algorithms (Demons, B-spline and Affine). The maximum deviations (> 15 mm) were found within both Demons and B-spline image registrations. In the upper part of the lungs the median deviation of 1.7 (mm) was significantly different (p < 0.02) relative to the median deviations of 2.0 (mm), found in the middle and lower parts of the lungs. The DSC revealed similar registration discrepancies among the three tested algorithms, with DSC values of 0.96, 0.97 and 0.91, for respectively Demons, B-spline and the Affine algorithms., Conclusion: Bronchial branch points were found useful to validate thoracic CT-CT image registration. Bronchial branch points identified local registration errors > 15 mm in both Demons and B-spline deformable algorithms.

Background: The prostate gland is delineated as the clinical target volume (CTV) in treatment planning of prostate cancer. Therefore, an accurate delineation is a prerequisite for efficient treatment. Accurate automated prostate segmentation methods facilitate the delineation of the CTV without inter-observer variation. The purpose of this study is to present an automated three-dimensional (3D) segmentation of the prostate using an active appearance model., Material and Methods: Axial T2-weighted magnetic resonance (MR) scans were used to build the active appearance model. The model was based on a principal component analysis of shape and texture features with a level-set representation of the prostate shape instead of the selection of landmarks in the traditional active appearance model. To achieve a better fit of the model to the target image, prior knowledge to predict how to correct the model and pose parameters was incorporated. The segmentation was performed as an iterative algorithm to minimize the squared difference between the target and the model image., Results: The model was trained using manual delineations from 30 patients and was validated using leave-one-out cross validation where the automated segmentations were compared with the manual reference delineations. The mean and median dice similarity coefficient was 0.84 and 0.86, respectively., Conclusion: This study demonstrated the feasibility for an automated prostate segmentation using an active appearance with results comparable to other studies.

Purpose: In image-guided radiotherapy of prostate cancer defining the clinical target volume often relies on magnetic resonance (MR). The task of transferring the clinical target volume from MR to standard planning computed tomography (CT) is not trivial due to prostate mobility. In this paper, an automatic local registration approach is proposed based on a newly developed removable Ni-Ti prostate stent., Methods: The registration uses the voxel similarity measure mutual information in a two-step approach where the pelvic bones are used to establish an initial registration for the local registration., Results: In a phantom study, the accuracy was measured to 0.97 mm and visual inspection showed accurate registration of all 30 data sets. The consistency of the registration was examined where translation and rotation displacements yield a rotation error of 0.41° ± 0.45° and a translation error of 1.67 ± 2.24 mm., Conclusions: This study demonstrated the feasibility for an automatic local MR-CT registration using the prostate stent.

Non-communicable diseases (NCDs) are receiving growing attention, which brings a unique opportunity to utilise solutions available to address them. These diseases are largely preventable; proven, cost-effective interventions are available; and when NCDs emerge, means exist to treat them, prevent complications, and to improve quality of life. Yet, there is a lack in progress in responding effectively to NCDs, and the current discussion and research focus predominantly on challenges rather than the opportunities, which this paper outlines.

Brain extraction is an important step in the analysis of brain images. The variability in brain morphology and the difference in intensity characteristics due to imaging sequences make the development of a general purpose brain extraction algorithm challenging. To address this issue, we propose a new robust method (BEaST) dedicated to produce consistent and accurate brain extraction. This method is based on nonlocal segmentation embedded in a multi-resolution framework. A library of 80 priors is semi-automatically constructed from the NIH-sponsored MRI study of normal brain development, the International Consortium for Brain Mapping, and the Alzheimer's Disease Neuroimaging Initiative databases. In testing, a mean Dice similarity coefficient of 0.9834±0.0053 was obtained when performing leave-one-out cross validation selecting only 20 priors from the library. Validation using the online Segmentation Validation Engine resulted in a top ranking position with a mean Dice coefficient of 0.9781±0.0047. Robustness of BEaST is demonstrated on all baseline ADNI data, resulting in a very low failure rate. The segmentation accuracy of the method is better than two widely used publicly available methods and recent state-of-the-art hybrid approaches. BEaST provides results comparable to a recent label fusion approach, while being 40 times faster and requiring a much smaller library of priors., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The purpose of intraoperative quality assessment of coronary artery bypass graft surgery is to confirm graft patency and disclose technical errors to reduce cardiac mortality, morbidity and improve clinical outcome for the patient. Epicardial ultrasound has been suggested as an alternative approach for quality assessment of anastomoses. To make a quantitative assessment of the anastomotic quality using ultrasound images, the vessel border has to be delineated to estimate the area of the vessel lumen. A tracking and segmentation algorithm was developed consisting of an active contour modeling approach and quality control of the segmentations. Evaluation of the tracking algorithm showed 91.96% of the segmentations were segmented correct with a mean error in height and width at 5.65% and 11.50% respectively.

Infant feeding is estimated to be responsible for 5%-20% of the burden of HIV transmission from mother to child. HIV positive women who cannot afford safe formula feeding are advised to practise exclusive breastfeeding (EBF) followed by prompt weaning. We conducted a qualitative study using observations and in-depth individual interviews to explore patterns of EBF as well as which factors motivate or hinder women to practice EBF. HIV positive women who intended to practice EBF from urban Malawi were purposively selected and interviewed. All women were well informed and had high knowledge on HIV as well as on EBF but much less knowledge on basic facts about breastfeeding. Despite their intentions less than half of the interviewed women managed to practice EBF and the barriers were explained by perceived lack of milk, lack of control over the feeding situation, felt and enacted stigma as well as poor counselling. Women who succeeded were older, had the explicit support of their husband and lived without the presence of their mother-in-law. Weaning at the age of 6 months was reported to be as difficult for the women as EBF. Intention itself is not a sufficient determinant of successful EBF unless a number of enabling factors come together. Prolonged breastfeeding is the cultural norm in Malawi and programs must be sensitive to social expectations to mothers and involve mothers-in-law and fathers in counselling of mothers who intend to practice EBF.

Frontotemporal dementia constitutes the third most prevalent neurodegenerative disease with dementia. We compared cortical structural changes in nine presymptomatic CHMP2B frontotemporal dementia mutation positive individuals with seven mutation negative family members. Using serial MRI scans with a mean interval of 16 months and surface based cortical segmentation we measured cortical thickness and volume, and quantified atrophy rates. Cortical thickness and atrophy rates were averaged within major lobes and focal effects were determined by parametric statistical maps. The volumetric atrophy rates in the presymptomatic CHMP2B mutation carriers were statistically significant, though of a lower magnitude than those previously reported in patients of other types of frontotemporal dementia. Cortical thickness measurements revealed cortical thinning in mutation carriers bilaterally in the frontal and occipital lobes, and in the left temporal lobe. Results indicated that cortical thickness has a higher sensitivity for detecting small changes than whole-brain volumetric measures. Comparing mutation carriers with non-carriers revealed increased atrophy rates in mutation carriers bilaterally in the inferio-temporal cortex, the superior frontal cortex, and the insular cortex. These findings indicated impairment of regions involved in both behaviour and language. The symptoms previously reported in clinical CHMP2B frontotemporal dementia patients are associated with the anatomically affected regions here found in the presymptomatic mutation carriers.

Aims: This study explores the knowledge, attitudes and practices among Somali and Sudanese immigrants in Denmark with regard to HIV/AIDS and condom use., Material and Methods: A 78-item questionnaire, divided into five thematic sections, was given to 192 purposively selected Sudanese and Somalis of both sexes, aged 18-49, who had lived in Denmark for one or more years. It was administered in Arabic and Somali in four locations and supplemented by 13 semi-structured interviews., Results: Education, sex, and nationality, but not length of residence in Denmark, were positively associated with knowledge about HIV/AIDS. Less than half of both men and women scored more than 70% on the knowledge portion of the questionnaire, while Sudanese knew more than Somalis. Men had a more negative attitude towards condoms than women, but greater knowledge about them. One-third of the women reported never having seen or heard of a condom, and almost half had never received information about condoms. Both sexes preferred receiving such information from the TV or friends instead of family doctors or HIV-positive individuals., Conclusions: This study suggests that knowledge about HIV/AIDS is low in these two Danish immigrant groups, both of which are characterized by reported incidence rates that are higher than the national average. The groups receive little information, while condom knowledge is particularly low among poorly educated women, and men have a negative attitude to condom use. The findings indicate a need for targeted, culturally sensitive HIV/AIDS information and advice.

As a joined project between Aalborg University and Aalborg Hospital Denmark, a neuro-surgical simulator is being developed. In this paper the objective of the project is outlined and an overview of the research activities within the project is given. Focus is on 3D modelling of the brain, deformable models and the development of two demonstrators, including one for training of punctuation of ventricle using visual and haptic feedback.