18F-fluorodeoxyglucose positron emission tomography for the assessment of endo-bronchial involvement in granulomatosis with polyangiitis.

Bronchial stenosis is an uncommon but potentially life-threatening complication of granulomatosis with polyangiitis (GPA). The development of lower respiratory tract stenoses in patients with GPA is thought to be the result of persistent inflammation of the cartilaginous tissue. New assessment methods for this severe GPA complication are highly needed. Herein, we show the value of 18F-fluorodeoxyglycose positron emission tomography/computed tomography (18F-FDG-PET/CT) in the diagnosis, prediction of progression to bronchial stenosis and response to treatment of endobronchial involvement in a patient with GPA.

Using Geant4 Monte Carlo toolkit to evaluate a low power X-ray tube generator configuration.

Monte Carlo technique has been widely used as an important tool to develop new irradiation equipment, prototype medical equipment parts, and test methodologies for dosimetry. In this manuscript, we present a methodology to design a low power X-ray tube generator using the Geant4 Monte Carlo toolkit. The simulations were performed considering a large number of variables, namely, the material composition of the target track, the window thickness, and the air pressure of the X-ray tube. The X-ray production was simulated considering monoenergetic electron beams impinging on targets of tungsten and copper with incident kinetic energies ranging from 20 keV to 60 keV and initial divergences from 5° to 30°. For the polyenergetic emission, a conservative approach with Gaussian energy distribution was adopted. The analysis indicates that among the evaluated parameters, the incident kinetic energy, and the target material produced the most notable changes in the spectra shape and conversion efficiency (CE), significantly impacting the X-ray tube design. The studies provide a reliable methodology to explore general configurations for X-ray tube generators, defining the best geometry, material compositions, and thicknesses to be used on spectroscopy applications.

Effectiveness of digital feedback on patient experience and 30-day complications after screening colonoscopy: a randomized health services study.

Background and study aims European guidelines (ESGE) recommend measuring patient experience and 30-day complication rate after colonoscopy. We compared digital and paper-based feedback on patients' experience and 30-day complications after screening colonoscopy. Patients and methods Screenees attending for primary screening colonoscopies in two centers from September 2015 to December 2016 were randomized (1:1) to an intervention arm (choice of feedback method) or control arm (routine paper-based feedback). Participants in the intervention arm could choose preferred feedback method (paper-based, automated telephone or online survey) and were contacted by automated telephone 30 days after colonoscopy to assess complications. Control group participants self-reported complications. Primary and secondary endpoints were response rates to feedback and complications questionnaire, respectively. Results There were 1,281 and 1,260 participants in the intervention and control arms, respectively. There was no significant difference in response rate between study groups (64.8 % vs 61.5 %; P  = 0.08). Free choice of feedback improved response for participants identified as poor responders: younger than 60 years (60.8 % vs 54.7 %; P  = 0.031), male (64.0 % vs 58.6 %; P  = 0.045) and in small non-public center (56.2 % vs 42.5 %; P  = 0.043). In the intervention arm, 1,168 participants (91.2 %) answered the phone call concerning complications. A total of 79 participants (6.2 %) reported complications, of which two (0.2 %) were verified by telephone as clinically relevant. No complications were self-reported in the control group. Conclusion The overall response rate was not significantly improved with digital feedback, yet the technology yielded significant improvement in participants defined as poor responders. Our study demonstrated feasibility and efficacy of digital patient feedback about complications after colonoscopy.

Bond-Breaking Efficiency of High-Energy Ions in Ultrathin Polymer Films.

Thin films of poly(methyl methacrylate) and poly(vinyl chloride) of different thickness are used to investigate the effect of spatial confinement on the efficiency of bond breaking induced by 2 MeV H^{+} and 2.1 GeV Bi ions. Effective cross sections for oxygen and chlorine loss are extracted for films down to a thickness of about 5 nm and are compared to theoretical estimations based on radial energy density profiles simulated with geant-dna. The cross sections are to a large extent thickness independent, indicating that bond breaking is dominated by short-range processes. This is in contrast to the strongly reduced efficiencies found recently for cratering induced by high-energy ions in similar ultrathin polymer films [Phys. Rev. Lett. 114, 118302 (2015)PRLTAO0031-900710.1103/PhysRevLett.114.118302].

Monte Carlo Simulation Used to Calculate Energy Correction Factor for Thermoluminescent Dosimeters Used by Occupational Workers on Pediatric Exams.

The main objective of this work is to simulate the X-ray scattered spectra by different pediatric phantoms (simulation of children subjected to barium meal procedures) to calculate an energy correction factor (ECF) to the reading of thermoluminescent dosimeters (TLDs). To perform this evaluation, the TLDs were positioned over three areas in two occupational workers: eyes, thyroid and hands. The Geant4 toolkit was used to define the spectra collected by TLDs, making possible to calculate the ECF. This work was developed in two stages: (1) evaluation of scattered spectra by different standard phantoms (newborn, 1, 5 and 10 years old); (2) definition of the ECF to the absorbed energy by each TLD. Geant4 shows to be a good toolkit to calculate the ECF and among the different characteristics evaluated, in this work, the TLD position and acceleration voltages are the most significant parameters that may influence the ECF calculated.

Identification of multiple nursery habitats of skates in the eastern Bering Sea.

The use of more than a single nursery habitat type is examined for oviparous elasmobranchs using data summarized from studies conducted on the Alaska skate Bathyraja parmifera and the Aleutian skate Bathyraja aleutica in the eastern Bering Sea. The eastern Bering Sea skate species use two discrete areas as nurseries, one for egg deposition and a second for newly emergent juveniles. Egg deposition sites were located along the outer shelf and upper slope near canyons in the eastern Bering Sea. Newly emergent juveniles were found along the outer and middle shelf for B. parmifera and deep-slope for B. aleutica, suggesting that habitat used by newly emergent juvenile skates is distinct from habitat used for egg deposition and embryo development. In reviewing many studies on oviparous elasmobranchs, similar patterns emerge of habitat use during their early life history. To distinguish these distinct habitats, appropriate terminology is proposed. Egg case nursery is suggested for areas of egg deposition and juvenile nursery is suggested for areas where juveniles aggregate after emergence. Criteria to describe each habitat type are outlined.

Determining vestibular hypofunction: start with the video-head impulse test.

Caloric testing is considered the 'reference standard' in determining vestibular hypofunction. Recently, the video-head impulse test (vHIT) was introduced. In the current study we aimed to assess the diagnostic value of the vHIT as compared to caloric testing in determining vestibular function. In a cross-sectional study between May 2012 and May 2013, we prospectively analysed patients with dizziness who had completed caloric testing and the vHIT. For the left and right vestibular system we calculated the mean vHIT gain. We used a gain cut-off value of 0.8 for the vHIT and presence of correction saccades to define an abnormal vestibular-ocular reflex. An asymmetrical ocular response of 22 % or more (Jongkees formula) or an irrigation response with a velocity below 15°/s was considered abnormal. We calculated sensitivity, specificity, positive and negative predictive values with 95 % confidence intervals for the dichotomous vHIT. Among 324 patients [195 females (60 %), aged 53 ± 17 years], 39 (12 %) had an abnormal vHIT gain and 113 (35 %) had an abnormal caloric test. Sensitivity was 31 % (23-40 %), specificity 98 % (95-99 %), positive predictive value was 88 % (74-95 %), and negative predictive value 73 % (67-77 %). In case of vHIT normality, additional caloric testing remains indicated and the vHIT does not replace the caloric test. However, the high positive predictive value of the vHIT indicates that an abnormal vHIT is strongly related to an abnormal caloric test result; therefore, additional caloric testing is not necessary. We conclude that the vHIT is clinically useful as the first test in determining vestibular hypofunction in dizzy patients.

Neighborhood socio-economic context and emergency department visits for dental care in a U.S. Midwestern metropolis.

OBJECTIVE: This study was to examine the association between emergency department (ED) visits for dental complaints and neighborhood socio-economic contexts of patients in a U.S. Midwestern metropolis. STUDY DESIGN: A retrospective study. METHODS: Deidentified data of ED visits for the period 2001-2010 from all facilities serving Kansas City, Missouri and 2007-2011 American Community Survey 5-Year Estimates data were used to determine odds of visit by neighborhood socio-economic characteristics at the ZIP code level. ED visits with diagnoses of International Classification of Disease 9th Revision codes related to toothache or tooth injury were included. ZIP code characteristics included percent of non-white population, median family income, percent of population 25 years and older with at least a high school degree, and percent of population with a language other than English spoken at home. Each ZIP code characteristic was divided into quartiles. Chi-square tests and two-level hierarchical linear modeling (HLM) were conducted. In the HLM, the outcome variable was whether to have an ED visit for dental complaints (yes/no), the first-level variables were characteristics of individual ED visits, and the second-level variables were ZIP code characteristics. RESULTS: The study population made 1,786,939 ED visits, of which 35,136 (1.9%) were for dental complaints. Among the patients making ED visits for dental complaints, 54.8% were female, 51.9% were younger adults aged 19-35 years, 48.7% were non-Hispanic black, and 35.5% used self-pay as the source of payment. After controlling the first-level variables, the HLM showed that the risk of ED visits for dental complaints significantly increased for individuals residing in ZIP Code Tabulation Areas with lower median family income, or a higher proportion of the population with a language rather than English spoken at home. CONCLUSIONS: Among socio-economic characteristics examined, median family income and percent of population with a language other than English spoken at home are important indicators of ED visits for dental complaints.

On development of functional brain connectivity in the young brain.

Our brain is a complex network of structurally and functionally interconnected regions, shaped to efficiently process and integrate information. The development from a brain equipped with basic functionalities to an efficient network facilitating complex behavior starts during gestation and continues into adulthood. Resting-state functional MRI (rs-fMRI) enables the examination of developmental aspects of functional connectivity (FC) and functional brain networks. This review will discuss changes observed in the developing brain on the level of network FC from a gestational age of 20 weeks onwards. We discuss findings of resting-state fMRI studies showing that functional network development starts during gestation, creating a foundation for each of the resting-state networks (RSNs) to be established. Visual and sensorimotor areas are reported to develop first, with other networks, at different rates, increasing both in network connectivity and size over time. Reaching childhood, marked fine-tuning and specialization takes place in the regions necessary for higher-order cognitive functions.

European guidelines for quality assurance in colorectal cancer screening and diagnosis: overview and introduction to the full supplement publication.

Population-based screening for early detection and treatment of colorectal cancer (CRC) and precursor lesions, using evidence-based methods, can be effective in populations with a significant burden of the disease provided the services are of high quality. Multidisciplinary, evidence-based guidelines for quality assurance in CRC screening and diagnosis have been developed by experts in a project co-financed by the European Union. The 450-page guidelines were published in book format by the European Commission in 2010.  They include 10 chapters and over 250 recommendations, individually graded according to the strength of the recommendation and the supporting evidence. Adoption of the recommendations can improve and maintain the quality and effectiveness of an entire screening process, including identification and invitation of the target population, diagnosis and management of the disease and appropriate surveillance in people with detected lesions. To make the principles, recommendations and standards in the guidelines known to a wider professional and scientific community and to facilitate their use in the scientific literature, the original content is presented in journal format in an open-access Supplement of Endoscopy. The editors have prepared the present overview to inform readers of the comprehensive scope and content of the guidelines.

Patterns and predictive factors of complications after endoscopic retrograde cholangiopancreatography.

BACKGROUND: With an increased use of magnetic resonance imaging, the indications for endoscopic retrograde cholangiopancreatography (ERCP) have changed. Consequently, the patterns and factors predictive of complications after ERCP performed during current routine clinical practice are not well known. METHODS: A prospective multicentre cohort study was undertaken in 11 Norwegian hospitals. Complications and mortality within 30 days after ERCP were analysed by univariable and multivariable regression analysis. RESULTS: There were 2808 ERCP procedures, of which 2573 (91·6 per cent) were therapeutic. More than half of the patients were aged 70 years or more. Common bile duct cannulation was achieved in 2557 procedures (91·1 per cent). Complications occurred in 327 (11·6 per cent) of the procedures, including cholangitis in 100 (3·6 per cent), pancreatitis in 88 (3·1 per cent), bleeding in 66 (2·4 per cent), perforation in 25 (0·9 per cent) and cardiovascular-respiratory events in 32 (1·1 per cent). In the multivariable regression analysis, older age, increasing American Society of Anesthesiologists fitness score, centre ERCP volumes of more than 150 procedures annually and precut sphincterotomy were predictive factors for severe complications. The overall 30-day mortality rate was 2·2 per cent (63 patients), with a procedure-related mortality rate of 1·4 per cent (39 patients). Malignancy was diagnosed in 46 (73 per cent) of the patients who died. CONCLUSION: ERCP is a procedure with considerable risk for complications. Morbidity and mortality are related to patient age and co-morbidity, as well as hospital volume of ERCP procedures and the type of intervention.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Colonoscopic surveillance following adenoma removal.

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on colonoscopic surveillance following adenoma removal includes 24 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of surveillance and other elements in the screening process, including multi-disciplinary diagnosis and management of the disease.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Quality assurance in endoscopy in colorectal cancer screening and diagnosis.

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on quality assurance in endoscopy includes 50 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of endoscopy and other elements in the screening process, including multidisciplinary diagnosis and management of the disease.

The NordICC Study: rationale and design of a randomized trial on colonoscopy screening for colorectal cancer.

BACKGROUND AND STUDY AIM: While colonoscopy screening is widely used in several European countries and the United States, there are no randomized trials to quantify its benefits. The Nordic-European Initiative on Colorectal Cancer (NordICC) is a multinational, randomized controlled trial aiming at investigating the effect of colonoscopy screening on colorectal cancer (CRC) incidence and mortality. This paper describes the rationale and design of the NordICC trial. STUDY DESIGN: Men and women aged 55 to 64 years are drawn from the population registries in the participating countries and randomly assigned to either once-only colonoscopy screening with removal of all detected lesions, or no screening (standard of care in the trial regions). All individuals are followed for 15 years after inclusion using dedicated national registries. The primary end points of the trial are cumulative CRC-specific death and CRC incidence during 15 years of follow-up. POWER ANALYSIS: We hypothesize a 50 % CRC mortality-reducing efficacy of the colonoscopy intervention and predict 50 % compliance, yielding a 25 % mortality reduction among those invited to screening. For 90 % power and a two-sided alpha level of 0.05, using a 2:1 randomization, 45 600 individuals will be randomized to control, and 22 800 individuals to the colonoscopy group. Interim analyses of the effect of colonoscopy on CRC incidence and mortality will be performed at 10-year follow-up. CONCLUSIONS: The aim of the NordICC trial is to quantify the effectiveness of population-based colonoscopy screening. This will allow development of evidence-based guidelines for CRC screening in the general population.

Reduced pain during screening colonoscopy with an ultrathin colonoscope: a randomized controlled trial.

BACKGROUND AND STUDY AIMS: Screening colonoscopy for colorectal cancer (CRC) is recommended in several countries, but uptake rates are often low. Fear of pain and also time-consuming costly sedation are barriers for colonoscopy, and thus development of colonoscopy equipment that decreases patient discomfort is worthwhile. This randomized controlled trial investigated the performance of an ultrathin colonoscope in CRC screening. PATIENTS AND METHODS: Consecutive participants in a colonoscopy screening trial were randomized to examination with an ultrathin prototype colonoscope or a standard colonoscope. The main outcome measure was pain during the examination. Participants rated pain (no, slight, moderate, severe) using a validated questionnaire. RESULTS: From 187 enrolled participants (80 women [43 %]), 162 (87 %) responded to the questionnaire. The study groups were similar regarding baseline characteristics. Pain scores were significantly lower in the prototype instrument group compared with the standard group (78 % vs. 29 % of patients with no pain in prototype and standard groups, respectively; odds ratio [OR] 0.11; 95 % confidence interval [CI] 0.06 - 0.23; P < 0.001). Cecal intubation rate was 98 % in the prototype group and 92 % in the standard group (P = 0.085). Sedation was used in 2 % and 7 % in the prototype and standard groups respectively (P = 0.12). Adenoma detection rate was 13 % in the prototype group vs. 24 % in the standard group (P = 0.052). CONCLUSION: The new ultrathin Olympus colonoscope decreases patient pain during screening colonoscopy. This feature may improve uptake and patient satisfaction in screening colonoscopy. Further study is needed to evaluate the lower adenoma detection rate.

Withdrawal time as a quality indicator for colonoscopy - a nationwide analysis.

BACKGROUND AND STUDY AIMS: A withdrawal time of at least 6 min has been recommended as a quality indicator for colonoscopy. One drawback of many of the studies that have investigated withdrawal time and produced conflicting results has been their single-center design involving few endoscopists. Therefore, the validity of withdrawal time as a quality measure remains unclear. This study explores the value of individual withdrawal time in a nationwide analysis. PATIENTS AND METHODS: This prospective cohort study comprised data from outpatient colonoscopies performed at 19 Norwegian centers from January to September 2009 and registered in the Norwegian Gastronet Quality Assurance (QA) program. The participating endoscopists were characterized by their median withdrawal time for visual colonoscopies (diagnostic colonoscopies without biopsy or therapy) and categorized into two visual withdrawal time (VWT) groups (< 6 min or ≥ 6 min) to analyze the predictive value of VWT for detection of one or more polyps ≥ 5 mm in diameter using multiple logistic regression models. RESULTS: The study included 4429 consecutive colonoscopies performed by 67 endoscopists. The adjusted odds ratio for the detection of polyps ≥ 5 mm was 1.21 (95 %CI 0.94 - 1.56, P = 0.14) for endoscopists with a median VWT ≥ 6 min compared with endoscopists with a median VWT < 6 min. CONCLUSION: Withdrawal time using 6 min as the threshold is not a strong predictor of the likelihood of finding a polyp during colonoscopy and should not be used as a quality indicator.

Incontinence after colonoscopy--an unrecognized and preventable problem. A cross-sectional study from the Gastronet quality assurance program.

BACKGROUND: Colonoscopy requires insufflation of gas for visualization of the bowel wall. Worldwide, this is usually done using air. The aim of the present study was to assess the risk of postcolonoscopy incontinence, and to investigate whether insufflation of CO2 instead of air may reduce this risk, since it is easily absorbed through the bowel mucosa. METHODS: This is a prospective multicenter study of colonoscopy patients undergoing bowel insufflation using air or CO2. A successive series of colonoscopies were reported to a national quality assurance program in Norway between January and December 2009 from 21 endoscopy centers with varying insufflation practices. The study comprised 7812 patients aged 18 years or older who were referred for outpatient colonoscopy. Of these, 5015 underwent colonoscopy performed using air and 2797 colonoscopy using CO2 insufflation. RESULTS: Patient-reported incontinence up to 24 h after colonoscopy was compared using binary logistic regression analysis for the type of gas used for insufflation. The air and CO2 patient groups were comparable with regard to age, sex, indication for colonoscopy, and sedation practice. Incontinence was reported by 336 out of 7812 patients (4.3%). Incontinence was significantly less frequent in the CO2 group than in the air group [2.1% versus 5.5%; adjusted odds ratio (OR) 0.38; 95%CI 0.28-0.50; P < 0.001]. Female patients had a higher risk of incontinence than men (adjusted OR 1.77; 95% CI 1.39-2.24; P < 0.001). CONCLUSION: About every 20th patient undergoing colonoscopy using standard air insufflation experiences postexamination incontinence. This proportion can be reduced by 60% by converting from air insufflation to insufflation with the absorbable CO2.

SPG20, a novel biomarker for early detection of colorectal cancer, encodes a regulator of cytokinesis.

Colorectal cancer is a common disease with high mortality. Suitable biomarkers for detection of tumors at an early curable stage would significantly improve patient survival. Here, we show that the SPG20 (spastic paraplegia-20) promoter, encoding the multifunctional Spartin protein, is hypermethylated in 89% of colorectal carcinomas, 78% of adenomas and only 1% of normal mucosa samples. SPG20 methylation was also present in a pilot series of stool samples and corresponding tumors from colorectal cancer patients. SPG20 promoter hypermethylation resulted in loss of mRNA expression in various cancer types and subsequent depletion of Spartin. We further showed that Spartin downregulation in cancer cells resulted in cytokinesis arrest, which was reversed when SPG20 methylation was inhibited. The present study identifies SPG20 promoter hypermethylation as a biomarker suitable for non-invasive detection of colorectal cancer, and a possible mechanism for cytokinesis arrest in colorectal tumorigenesis.

Patient satisfaction with on-demand sedation for outpatient colonoscopy.

BACKGROUND AND STUDY AIM: To reduce the costs of colonoscopy the feasibility of unsedated procedures has been explored. The aims of our study were to assess patient satisfaction with on-demand sedation and identify factors related to painful colonoscopy. PATIENTS AND METHODS: The Norwegian Gastronet quality assurance documentation tools consist of endoscopy reports (completed on site) and a patient satisfaction questionnaire (completed by the patient on the day after colonoscopy). Data were collected from January 1 2004 to December 31 2006. Colonoscopies reported to be moderately or severely painful were defined as "painful colonoscopy." RESULTS: Nine endoscopy centers representing 86 endoscopists reported 14 915 examinations and 12 354 patient reports were returned (83 % response rate). Patient satisfaction with service and information given was greater than 95 % for all centers. Mean rate of painful colonoscopy was 34 % and mean sedation rate 34 %. Odds ratio (OR) for painful colonoscopy was 2.2 ( P < 0.001) when sedation was given. The ORs for painful colonoscopy were similar for all but one center (no. 4) with OR 1.6 ( P = 0.04), while the OR for giving sedation was higher for all but one center (no. 1) compared with the reference center (ORs 2.2 to 7.5, all P-values < 0.001). CONCLUSION: A surprisingly high rate of painful colonoscopy was found. High sedation rates were not associated with low rates of painful colonoscopy. Recommending increased sedation rates as the only intervention to improve suboptimal performance might not lead to lower rates of painful colonoscopy.