To determine the accuracy and sensitivity for dual-energy computed tomography (DECT) discrimination of uric acid (UA) stones from other (non-UA) renal stones in a commercially implemented product.
...Forty human renal stones comprising uric acid (n=16), hydroxyapatite (n=8), calcium oxalate (n=8), and cystine (n=8) were inserted in four porcine kidneys (10 each) and placed inside a 32-cm water tank anterior to a cadaver spine. Spiral dual-energy scans were obtained on a dual-source, 64-slice computed tomography (CT) system using a clinical protocol and automatic exposure control. Scanning was performed at two different collimations (0.6 mm and 1.2 mm) and within three phantom sizes (medium, large, and extra large) resulting in a total of six image datasets. These datasets were analyzed using the dual-energy software tool available on the CT system for both accuracy (number of stones correctly classified as either UA or non-UA) and sensitivity (for UA stones). Stone characterization was correlated with micro-CT.
For the medium and large phantom sizes, the DECT technique demonstrated 100% accuracy (40/40), regardless of collimation. For the extra large phantom size and the 0.6-mm collimation (resulting in the noisiest dataset), three (two cystine and one small UA) stones could not be classified (93% accuracy and 94% sensitivity). For the extra large phantom size and the 1.2-mm collimation, the dual-energy tool failed to identify two small UA stones (95% accuracy and 88% sensitivity).
In an anthropomorphic phantom model, dual-energy CT can accurately discriminate uric acid stones from other stone types.
To test the hypothesis that duration of delirium in the intensive care unit is an independent predictor of long-term cognitive impairment after critical illness requiring mechanical ventilation.
...Prospective cohort study.
Medical intensive care unit in a large community hospital in the United States.
Mechanically ventilated medical intensive care unit patients who were assessed daily for delirium while in the intensive care unit and who underwent comprehensive cognitive assessments 3 and 12 mos after discharge.
Of 126 eligible patients, 99 survived>or=3 months after critical illness; long-term cognitive outcomes were obtained for 77 (78%) patients. Median age was 61 yrs, 51% were admitted with sepsis/acute respiratory distress syndrome, and median duration of delirium was 2 days. At 3-mo and 12-mo follow-up, 79% and 71% of survivors had cognitive impairment, respectively (with 62% and 36% being severely impaired). After adjusting for age, education, preexisting cognitive function, severity of illness, severe sepsis, and exposure to sedative medications in the intensive care unit, increasing duration of delirium was an independent predictor of worse cognitive performance-determined by averaging age-adjusted and education-adjusted T-scores from nine tests measuring seven domains of cognition-at 3-mo (p=.02) and 12-mo follow-up (p=.03). Duration of mechanical ventilation, alternatively, was not associated with long-term cognitive impairment (p=.20 and .58).
In this study of mechanically ventilated medical intensive care unit patients, duration of delirium (which is potentially modifiable) was independently associated with long-term cognitive impairment, a common public health problem among intensive care unit survivors.
To characterize survivors' employment status after critical illness and to determine if duration of delirium during hospitalization and residual cognitive function are each independently associated ...with decreased employment.
Prospective cohort investigation with baseline and in-hospital clinical data and follow-up at 3 and 12 months.
Medical and surgical ICUs at two tertiary-care hospitals.
Previously employed patients from the Bringing to Light the Risk Factors and Incidence of Neuropsychological Dysfunction in ICU Survivors study who survived a critical illness due to respiratory failure or shock were evaluated for global cognition and employment status at 3- and 12-month follow-up.
We used multivariable logistic regression to evaluate independent associations between employment at both 3 and 12 months and global cognitive function at the same time point, and delirium during the hospital stay. At 3-month follow-up, 113 of the total survival cohort of 448 (25%) were identified as being employed at study enrollment. Of these, 94 survived to 12-month follow-up. At 3- and 12-month follow-up, 62% and 49% had a decrease in employment, 57% and 49% of whom, respectively, were newly unemployed. After adjustment for physical health status, depressive symptoms, marital status, level of education, and severity of illness, we did not find significant predictors of employment status at 3 months, but better cognition at 12 months was marginally associated with lower odds of employment reduction at 12 months (odds ratio, 0.49; p = 0.07).
Reduction in employment after critical illness was present in the majority of our ICU survivors, approximately half of which was new unemployment. Cognitive function at 12 months was a predictor of subsequent employment status. Further research is needed into the potential relationship between the impact of critical illness on cognitive function and employment status.
Survivors of critical illness are frequently left with long-lasting disability. The association between delirium and disability in critically ill patients has not been described. We hypothesized that ...the duration of delirium in the ICU would be associated with subsequent disability and worse physical health status following a critical illness.
Prospective cohort study nested within a randomized controlled trial of a paired sedation and ventilator weaning strategy.
A single-center tertiary-care hospital.
One hundred twenty-six survivors of a critical illness.
Confusion Assessment Method for the ICU, Katz activities of daily living, Functional Activities Questionnaire (measuring instrumental activities of daily living), Medical Outcomes Study 36-item Short Form General Health Survey Physical Components Score, and Awareness Questionnaire were used. Associations between delirium duration and outcomes were determined via proportional odds logistic regression with generalized estimating equations (for Katz activities of daily living and Functional Activities Questionnaire scores) or via generalized least squares regression (for Medical Outcomes Study 36-item Short Form General Health Survey Physical Components Score and Awareness Questionnaire scores). Excluding patients who died prior to follow-up but including those who withdrew or were lost to follow-up, we assessed 80 of 99 patients (81%) at 3 months and 63 of 87 patients (72%) at 12 months. After adjusting for covariates, delirium duration was associated with worse activities of daily living scores (p = 0.002) over the course of the 12-month study period but was not associated with worse instrumental activities of daily living scores (p = 0.15) or worse Medical Outcomes Study 36-item Short Form General Health Survey Physical Components Score (p = 0.58). Duration of delirium was also associated with lower Awareness Questionnaire Motor/Sensory Factors scores (p 0.02).
In the setting of critical illness, longer delirium duration is independently associated with increased odds of disability in activities of daily living and worse motor-sensory function in the following year. These data point to a need for further study into the determinants of functional outcomes in ICU survivors.
Until relatively recently, critical care practitioners have focused on the survival of their patients and not on long-term outcomes. The incidence of chronic neurocognitive dysfunction has been ...underestimated and underreported, and only recently has it been studied in critically ill patients. However, neurocognitive outcomes have been the subject of extensive investigation in other medical populations for many years.
Review of the current literature regarding long-term neurocognitive outcomes following critical illness.
Data from studies to date indicate that critical illness can lead to significant neurocognitive impairments. The neurocognitive impairments persist for months and years, and may have important consequences for quality of life, the ability to return to work, overall functional ability, and substantial economic costs. The mechanisms of the neurocognitive impairments are not fully understood but likely include delirium, hypoxia, glucose dysregulation, metabolic derangements, inflammation, and the effects of sedatives and narcotics among other factors. The contributions of these factors may be particularly significant in patients with preexisting vulnerabilities for the development of cognitive impairments such as mild cognitive impairment, dementia, prior traumatic brain injury, or other comorbid disorders associated with neurocognitive impairments.
Current research indicates that neurocognitive sequelae following critical illness are common, may be permanent, and are associated with impairments in daily function, decreased quality of life, and an inability to return to work. Research needs to be done to better understand the prevalence, nature, risk factors, and nuances of the neurocognitive impairments observed in ICU survivors.
Purpose
To investigate multiple deep learning methods for automated segmentation (auto‐segmentation) of the parotid glands, submandibular glands, and level II and level III lymph nodes on magnetic ...resonance imaging (MRI). Outlining radiosensitive organs on images used to assist radiation therapy (radiotherapy) of patients with head and neck cancer (HNC) is a time‐consuming task, in which variability between observers may directly impact on patient treatment outcomes. Auto‐segmentation on computed tomography imaging has been shown to result in significant time reductions and more consistent outlines of the organs at risk.
Methods
Three convolutional neural network (CNN)‐based auto‐segmentation architectures were developed using manual segmentations and T2‐weighted MRI images provided from the American Association of Physicists in Medicine (AAPM) radiotherapy MRI auto‐contouring (RT‐MAC) challenge dataset (n = 31). Auto‐segmentation performance was evaluated with segmentation similarity and surface distance metrics on the RT‐MAC dataset with institutional manual segmentations (n = 10). The generalizability of the auto‐segmentation methods was assessed on an institutional MRI dataset (n = 10).
Results
Auto‐segmentation performance on the RT‐MAC images with institutional segmentations was higher than previously reported MRI methods for the parotid glands (Dice: 0.860 ± 0.067, mean surface distance MSD: 1.33 ± 0.40 mm) and the first report of MRI performance for submandibular glands (Dice: 0.830 ± 0.032, MSD: 1.16 ± 0.47 mm). We demonstrate that high‐resolution auto‐segmentations with improved geometric accuracy can be generated for the parotid and submandibular glands by cascading a localizer CNN and a cropped high‐resolution CNN. Improved MSDs were observed between automatic and manual segmentations of the submandibular glands when a low‐resolution auto‐segmentation was used as prior knowledge in the second‐stage CNN. Reduced auto‐segmentation performance was observed on our institutional MRI dataset when trained on external RT‐MAC images; only the parotid gland auto‐segmentations were considered clinically feasible for manual correction (Dice: 0.775 ± 0.105, MSD: 1.20 ± 0.60 mm).
Conclusions
This work demonstrates that CNNs are a suitable method to auto‐segment the parotid and submandibular glands on MRI images of patients with HNC, and that cascaded CNNs can generate high‐resolution segmentations with improved geometric accuracy. Deep learning methods may be suitable for auto‐segmentation of the parotid glands on T2‐weighted MRI images from different scanners, but further work is required to improve the performance and generalizability of these methods for auto‐segmentation of the submandibular glands and lymph nodes.
Decades-old, common ICU practices including deep sedation, immobilization, and limited family access are being challenged. We endeavoured to evaluate the relationship between ABCDEF bundle ...performance and patient-centered outcomes in critical care.
Prospective, multicenter, cohort study from a national quality improvement collaborative.
68 academic, community, and federal ICUs collected data during a 20-month period.
15,226 adults with at least one ICU day.
We defined ABCDEF bundle performance (our main exposure) in two ways: 1) complete performance (patient received every eligible bundle element on any given day) and 2) proportional performance (percentage of eligible bundle elements performed on any given day). We explored the association between complete and proportional ABCDEF bundle performance and three sets of outcomes: patient-related (mortality, ICU and hospital discharge), symptom-related (mechanical ventilation, coma, delirium, pain, restraint use), and system-related (ICU readmission, discharge destination). All models were adjusted for a minimum of 18 a priori determined potential confounders.
Complete ABCDEF bundle performance was associated with lower likelihood of seven outcomes: hospital death within 7 days (adjusted hazard ratio, 0.32; CI, 0.17-0.62), next-day mechanical ventilation (adjusted odds ratio AOR, 0.28; CI, 0.22-0.36), coma (AOR, 0.35; CI, 0.22-0.56), delirium (AOR, 0.60; CI, 0.49-0.72), physical restraint use (AOR, 0.37; CI, 0.30-0.46), ICU readmission (AOR, 0.54; CI, 0.37-0.79), and discharge to a facility other than home (AOR, 0.64; CI, 0.51-0.80). There was a consistent dose-response relationship between higher proportional bundle performance and improvements in each of the above-mentioned clinical outcomes (all p < 0.002). Significant pain was more frequently reported as bundle performance proportionally increased (p = 0.0001).
ABCDEF bundle performance showed significant and clinically meaningful improvements in outcomes including survival, mechanical ventilation use, coma, delirium, restraint-free care, ICU readmissions, and post-ICU discharge disposition.
Objective: Childhood overweight and obesity have increased substantially in the past two decades, raising concerns about their psychosocial and cognitive consequences. We examined the associations ...between academic performance (AP), cognitive functioning (CF), and increased BMI in a nationally representative sample of children.
Methods and Procedures: Participants were 2,519 children aged 8–16 years, who completed a brief neuropsychological battery and measures of height and weight as a part of the Third National Health and Nutrition Examination Survey, a cross‐sectional survey conducted between 1988 and 1994. Z‐scores were calculated for each neuropsychological test, and poor performance was defined as z‐score <2.
Results: The association between BMI and AP was not significant after adjusting for parental/familial characteristics. However, the associations between CF remained significant after adjusting for parental/familial characteristic, sports participation, physical activity, hours spent watching TV, psychosocial development, blood pressure, and serum lipid profile. Z‐scores on block design (a measure of visuospatial organization and general mental ability) among overweight children and children at risk of overweight were below those of normal‐weight children by 0.22 (s.e. = 0.16) and 0.10 (s.e. = 0.10) unit, respectively (P for trend <0.05). The odds of poor performance on block design were 1.97 (95% confidence interval: 1.01–3.83) and 2.80 (1.16–6.75), respectively, among children at risk or overweight compared to normal‐weight peers.
Discussion: Increased body weight is independently associated with decreased visuospatial organization and general mental ability among children. Future research is needed to determine the nature, persistence, and functional significance of this association.
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