Optimizing Use of High-Sensitivity Troponin for Risk-Stratification of Acute Pulmonary Embolism.

BACKGROUND: High-sensitivity troponin T (HS-TnT) may improve risk-stratification in hemodynamically stable acute pulmonary embolism (PE), but an optimal strategy for combining this biomarker with clinical risk-stratification tools has not been determined. STUDY HYPOTHESIS: We hypothesized that different HS-TnT cutoff values may be optimal for identifying (1) low-risk patients who may be eligible for outpatient management and (2) patients at increased risk of clinical deterioration who might benefit from advanced PE therapies. METHODS: Retrospective analysis of hemodynamically stable patients in the University of Michigan acute ED-PE registry with available HS-TnT values. Primary and secondary outcomes were 30-day mortality and need for intensive care unit-level care. Receiver operating characteristic curves were used to determine optimal HS-TnT cutoffs in the entire cohort, and for those at higher risk based on the simplified Pulmonary Embolism Severity Index (PESI) or imaging findings. RESULTS: The optimal HS-TnT cutoff in the full cohort, 12 pg/mL, was significantly associated with 30-day mortality (odds ratio [OR]: 3.94, 95% confidence interval [CI]: 1.48-10.50) and remained a significant predictor after adjusting for the simplified PESI (sPESI) score and serum creatinine (adjusted OR: 3.05, 95% CI: 1.11-8.38). A HS-TnT cutoff of 87 pg/mL was associated with 30-day mortality (OR: 5.01, 95% CI: 2.08-12.06) in patients with sPESI ≥1 or right ventricular dysfunction. CONCLUSION: In this retrospective, single-center study of acute PE patients, we identified distinct optimal HS-TnT values for different clinical uses-a lower cutoff, which identified low-risk patients even in the absence of other risk-stratification methods, and a higher cutoff, which was strongly associated with adverse outcomes in patients at increased risk.

Adverse childhood experiences and early initiation of substance use: A survival analysis.

OBJECTIVE: Early adversity, such as adverse childhood experiences (ACEs), is a risk factor for the development of substance use disorder (SUD). ACEs are associated with earlier initiation of substance use. This study examined the relationship between ACEs and age of initiation of substance use using survival analysis. It is hypothesized that individuals with higher ACEs will have an earlier age of initiation. METHOD: Participants were recruited from the University of Kentucky's Laboratory for Human Behavioral Pharmacology. Participants were 18 years or older, English speaking, and actively engaged in substance use. Participants were not in substance abuse treatment nor were they seeking treatment. ACE scores were calculated, and age of substance use initiation was recorded. A Cox proportional hazard model was used to examine the effect of ACE score on age of substance use initiation. RESULTS: A total of 107 participants completed the study. An average number of 2.3 ACEs (SD = 2.2) were endorsed with 24% of participants reporting 4 or more ACEs. Higher ACE scores were associated with cigarette smoking and non-medical prescription opioid use onset ( hazard ratio (HR) = 1.14, 95% CI=1.02-1.28, p = 0.02, and HR=1.19, 95% CI = 1.04-1.37, p = 0.01, respectively. CONCLUSIONS: A significant association was found between higher ACE scores and earlier initiation of cigarette and non-medical prescription opioid use, consistent with prior research. Primary prevention of ACEs, screening for ACEs during childhood, and interventions for ACEs if detected, may help to reduce the risk of substance use/SUD in adulthood.

Prediction of in-hospital deterioration in normotensive pulmonary embolism remains elusive: external validation of the calgary acute pulmonary embolism score.

Acute pulmonary embolism (PE) is a frequently diagnosed condition. Prediction of in-hospital deterioration is challenging with current risk models. The Calgary Acute Pulmonary Embolism (CAPE) score was recently derived to predict in-hospital adverse PE outcomes but has not yet been externally validated. Retrospective cohort study of normotensive acute pulmonary embolism cases diagnosed in our emergency department between 2017 and 2019. An external validation of the CAPE score was performed in this population for prediction of in-hospital adverse outcomes and a secondary outcome of 30-day all-cause mortality. Performance of the simplified Pulmonary Embolism Severity Index (sPESI) and Bova score was also evaluated. 712 patients met inclusion and exclusion criteria, with 536 patients having a sPESI score of 1 or more. Among this population, the CAPE score had a weak discriminative power to predict in-hospital adverse outcomes, with a calculated c-statistic of 0.57. In this study population, an external validation study found weak discriminative power of the CAPE score to predict in-hospital adverse outcomes among normotensive PE patients. Further efforts are needed to define risk assessment models that can identify normotensive PE patients at risk for in hospital deterioration. Identification of such patients will better guide intensive care utilization and invasive procedural management of PE.

Predicting post-discharge venous thromboembolism and bleeding among medical patients: External validation of a novel risk score utilizing ubiquitous biomarkers.

BACKGROUND: Post-hospitalization thromboprophylaxis can reduce venous thromboembolism (VTE) risk for non-surgical patients but may carry bleeding risks. We aimed to externally validate the Intermountain Risk Scores for hospital-associated venous thromboembolism (HA-VTE IMRS) and major bleeding (HA-MB IMRS) for VTE and bleeding outcomes. METHODS: Retrospective cohort study of adult patients discharged alive from medical services between 2015 and 2019. HA-VTE IMRS and HA-MB IMRS were calculated at the time of hospital discharge and dichotomized as high- or low-risk as described in the derivation manuscript. 90-day post-discharge VTE outcomes were assessed from diagnostic radiology reports, and bleeding outcomes were assessed using ICD-10 codes and blood bank transfusion records. RESULTS: Among 113,578 patients in the study, 66,340 patients (58.4 %) had a low-risk HA-VTE IMRS <7, versus 47,238 (41.6 %) high-risk ≥7. For bleed prediction, 71,576 patients (63 %) had a low-risk HA-MB IMRS <8, versus 42,002 (37 %) high-risk ≥8. VTE incidence was 1.1 % and 0.6 % while major bleeding incidence was 1.3 % and 0.1 % in high-risk versus low-risk cohorts, respectively. AUCs for VTE and bleed outcome discrimination were 0.59 and 0.78, respectively. Patients with a combined high-risk VTE score and low-risk bleeding score comprised 14.5 % of the population. CONCLUSION: In this external validation study, the HA-VTE IMRS had poor discrimination for VTE but the HA-MB IMRS had good discriminatory ability for major bleeding events. A sizable minority of patients were categorized as high VTE risk with low bleed risk, a population which may have an optimal risk-benefit profile for post-hospital thromboprophylaxis.

Adverse Clinical Outcomes Among Patients With Acute Low-risk Pulmonary Embolism and Concerning Computed Tomography Imaging Findings.

Importance: Most patients presenting to US emergency departments (EDs) with acute pulmonary embolism (PE) are hospitalized, despite evidence from multiple society-based guidelines recommending consideration of outpatient treatment for those with low risk stratification scores. One barrier to outpatient treatment may be clinician concern regarding findings on PE-protocol computed tomography (CTPE), which are perceived as high risk but not incorporated into commonly used risk stratification tools. Objective: To evaluate the association of concerning CTPE findings with outcomes and treatment of patients in the ED with acute, low-risk PE. Design, Setting, and Participants: This cohort study used a registry of all acute PEs diagnosed in the adult ED of an academic medical center from October 10, 2016, to December 31, 2019. Acute PE cases were divided into high- and low-risk groups based on PE Severity Index (PESI) class alone or using a combination of PESI class and biomarker results. The low-risk group was further divided based on the presence of concerning CTPE findings: (1) bilateral central embolus, (2) right ventricle-to-left ventricle ratio greater than 1.0, (3) right ventricle enlargement, (4) septal abnormality, or (5) pulmonary infarction. Data analysis was conducted from June to October 2022. Main Outcomes and measures: The primary outcome was all-cause mortality at 7 and 30 days. Secondary outcomes included hospitalization, length of stay, need for intensive care, use of echocardiography and/or bedside ultrasonography, and activation of the PE response team (PERT) . Results: Of 817 patients (median [IQR] age, 58 [47-71] years; 417 (51.0%) female patients; 129 [15.8%] Black and 645 [78.9%] White patients) with acute PEs, 331 (40.5%) were low risk and 486 (59.5%) were high risk by PESI score. Clinical outcomes were similar for all low-risk patients, with no 30-day deaths in the low-risk group with concerning CTPE findings (0 of 151 patients) vs 4 of 180 (2.2%) in the low-risk group without concerning CTPE findings and 88 (18.1%) in the high-risk group (P < .001). Low-risk patients with concerning CTPE findings were less frequently discharged from the ED than those without concerning CTPE findings (3 [2.0%] vs 14 [7.8%]; P = .01) and had more frequent echocardiography (87 [57.6%] vs 49 [27.2%]; P < .001) and PERT activation for consideration of advanced therapies (34 [22.5%] vs 11 [6.1%]; P < .001). Conclusions and Relevance: In this single-center study, CTPE findings widely believed to confer high risk were associated with increased hospitalization and resource utilization in patients with low-risk PE but not short-term adverse clinical outcomes.

Symptoms Suggestive of Postpulmonary Embolism Syndrome and Utilization of Diagnostic Testing.

Background: Persistent symptoms of chest pain, dyspnea, fatigue, lightheadedness, and/or syncope more than 3 months after an acute pulmonary embolism (PE) are collectively classified as postpulmonary embolism syndrome (PPES). Although PPES is increasingly recognized as an important long-term sequel of acute PE, its contemporary incidence is unclear. Furthermore, the utilization of diagnostic testing for further phenotypic characterization of these patients is unknown. This study aimed to define the incidence of PPES and evaluate the utilization of diagnostic tests among a national cohort of patients with PE. Methods: Retrospective cohort study was performed using the national administrative database, Clinformatics DataMart Database (Optum Insight), and included adult patients (18 years or older) with no history of acute PE or pulmonary hypertension, diagnosed with acute PE between October 1, 2016, and December 31, 2018. With acute PE event as the exposure, the incidence of symptoms consistent with PPES and diagnostic test utilization among patients with PPES were evaluated. Results: Of 21,297 incident patients with acute PE, 11,969 (56.2%) showed ≥1 symptom of PPES, which was new since their pre-PE baseline. New dyspnea was the most common and noted in 3268/15,203 (21.5%) patients, followed by new malaise or fatigue in 2894/15,643 (18.5%) patients. Among the 11,969 patients with PPES, 5128 (42.8%) received ≥1 diagnostic test, with 3242 (27%) receiving a computed tomography pulmonary angiogram, 2997 (25%) receiving an echocardiogram, and 325 (2.7%) received a ventilation-perfusion scan within 3-12 months after PE. Significantly lower use of diagnostic testing was noted in patients older than 65 years (adjusted odds ratio, 0.89; 95% CI, 0.81-0.98). Conclusions: Symptoms consistent with PPES are common after acute PE, occurring in more than half of the patients. Diagnostic imaging for further phenotypic characterization is used in less than half of such patients with PPES.

Percutaneous Treatments for Pulmonary Hypertension: Reviewing the Growing Procedural Role for Interventional Cardiology.

Pulmonary arterial hypertension is a common and highly morbid medical problem resulting in elevated pulmonary arterial pressures and pulmonary vascular resistance. Medical therapies are costly, and not always well-tolerated. Surgical therapies such as pulmonary endarterectomy and lung transplantation are limited to a small subset of patients due to various patient, disease, or institutional factors. Over the past decade, there has been growing investigation into endovascular interventional therapies for patients with pulmonary hypertension such as balloon pulmonary angioplasty and pulmonary denervation. In this review, we describe the current status, future directions, and our recommendations on technical considerations with these therapies.

Shoulder Function Assessment After Head And Neck Reconstruction With Pedicled Supraclavicular Flap.

The supraclavicular artery flap is used for reconstruction of defects of the head and neck. One of the major implications of this procedure is injury to the nerve roots of C3 and C4 of the superficial cervical plexus, which provides sensation over the clavicle, shoulder and proximal chest, thereby causing problems in overall shoulder function. The objective of this study was to assess shoulder function, range of motion, pain, daily activities and overall satisfaction of the patient after using this flap. This study was conducted at the Department of Plastic & Reconstructive Surgery, Dow University of Health Sciences & Dr. Ruth KM Pfau Civil Hospital Karachi, Pakistan, from May 2015 to November 2018. Supraclavicular flap was used in 35 patients who underwent soft tissue reconstruction of defect of the neck after release of post burn contracture. Penn Shoulder Score and Constant Murley Score were used as assessment tools. Assessment by Penn Shoulder Score resulted in 25 (71.4%) patients within the upper quartile and 10 (18.6%) patients within the lower quartile. Constant Murley Score showed 19 (54.2%) of patients had 161°-180° shoulder abduction and lateral elevation. Forward flexion of 161°-180° was seen in 17 (48.5%) patients, 17 (48.5%) had internal rotation till the inter scapular region, 15 (42.8%) had no impairment of external rotation, 19 (54.2%) patients had no impairment of work/recreation, 25 (71.4%) had felt no change in their sleep and 22 (62.8%) were able to position their arm above their head. Overall parameters indicate better function, good range of motion, less pain, resumption of daily activities, and overall satisfaction.

Le lambeau pédiculé supraclaviculaire est utilisé pour la reconstruction cervico- faciale. Sa complication principale est la lésion des racines C3 et C4 du plexus cervical superficiel, responsables de la sensibilité de la région claviculaire, de l'épaule et de la partie haute du thorax entraînant des troubles de la fonction de l'épaule. Cette étude avait pour but d'évaluer la fonction motrice de l'épaule, la douleur, les activités quotidiennes et la satisfaction des patients après ce type de chirurgie. Elle a été réalisée dans le service chirurgie plastique et reconstructrice de l'hôpital civil de Karachi entre mai 2015 et novembre 2018, auprès de 35 patients ayant bénéficié d'une reconstruction cervico- faciale par lambeau supraclaviculaire pour bride post- brûlure. Le score d'épaule de Penn et celui de Constant- Murley ont été utilisés. Vingt- cinq (71,4%) des patients étaient classés dans le quart supérieur du score de Penn, et 10 (18,6%) dans le quart inférieur. Dix- neuf (54,2%) patients avaient une élévation latérale et une abduction entre 161 et 180°, 17 (48,5%) une flexion antérieure entre 161 et 180° ou une rotation interne jusqu'à la région interscapulaire. Quinze (42,8%) patients avaient une rotation externe normale, 19 (54,2%) n'avaient aucune gêne dans la vie courante, 25 (71,4%) avaient un sommeil normal et 22 (62,8%) pouvaient positionner leur bras au- dessus de la tête. Globalement, la fonction est améliorée, les amplitudes sont bonnes, la douleur est diminuée, les activités quotidiennes sont restituées et les patients sont satisfaits.

Volumetric laser endomicroscopy and its application to Barrett's esophagus: results from a 1,000 patient registry.

Volumetric laser endomicroscopy (VLE) uses optical coherence tomography (OCT) for real-time, microscopic cross-sectional imaging. A US-based multi-center registry was constructed to prospectively collect data on patients undergoing upper endoscopy during which a VLE scan was performed. The objective of this registry was to determine usage patterns of VLE in clinical practice and to estimate quantitative and qualitative performance metrics as they are applied to Barrett's esophagus (BE) management. All procedures utilized the NvisionVLE Imaging System (NinePoint Medical, Bedford, MA) which was used by investigators to identify the tissue types present, along with focal areas of concern. Following the VLE procedure, investigators were asked to answer six key questions regarding how VLE impacted each case. Statistical analyses including neoplasia diagnostic yield improvement using VLE was performed. One thousand patients were enrolled across 18 US trial sites from August 2014 through April 2016. In patients with previously diagnosed or suspected BE (894/1000), investigators used VLE and identified areas of concern not seen on white light endoscopy (WLE) in 59% of the procedures. VLE imaging also guided tissue acquisition and treatment in 71% and 54% of procedures, respectively. VLE as an adjunct modality improved the neoplasia diagnostic yield by 55% beyond the standard of care practice. In patients with no prior history of therapy, and without visual findings from other technologies, VLE-guided tissue acquisition increased neoplasia detection over random biopsies by 700%. Registry investigators reported that VLE improved the BE management process when used as an adjunct tissue acquisition and treatment guidance tool. The ability of VLE to image large segments of the esophagus with microscopic cross-sectional detail may provide additional benefits including higher yield biopsies and more efficient tissue acquisition. Clinicaltrials.gov NCT02215291.

Hospital Medicine and Fellowship Program in Rural North Dakota - A Multifaceted Success Story.

INTRODUCTION: Recruitment of hospitalists and primary care physicians for Critical Access Hospitals and tertiary care hospitals in North Dakota is difficult. To address this challenge, 2 programs were implemented in Bismarck, North Dakota. METHODS: St. Alexius Medical Center created a hospitalist fellowship training program in collaboration with the University of North Dakota School of Medicine and Health Sciences and physicians willing to work in Critical Access Hospitals were offered a joint appointment to teach hospitalist fellows and obtain a clinical academic appointment at the university. RESULTS: Since it was created in 2012, 84 physicians have applied for 13 fellowships. Of the 11 fellows who have completed the program, 64% (7/11) remained in North Dakota to practice. CONCLUSIONS: Physicians are more likely to work in a rural Critical Access Hospital if they spend time working at a tertiary care center and have clinical academic appointments. Where recruitment is challenging, hospitalist fellowship programs are helpful in meeting the health care workforce demand.

Incidence of venous thromboembolism in different ethnic groups: a regional direct comparison study.

BACKGROUND: There are few studies that directly compare the variation in incidence of venous thromboembolism (VTE) according to ethnicity. OBJECTIVE: The aim of this study was to compare the rates of VTE, deep venous thrombosis (DVT) and pulmonary embolism (PE) among different ethnic groups. METHOD: The cases diagnosed with VTE, DVT and PE for a period between March 2004 and June 2009 were identified through the hospital-based database system. The 2006 New Zealand Census data were used to calculate the rate of diagnosis. RESULTS: The observed annual incidence of VTE during this period was 81.6 per 100000 population. The relative risks of VTE when comparing European subjects with Maori, Pacific Island and Asian subjects after age standardization were 1.98 (95% confidence interval [CI], 1.63-2.41), 3.22 (95% CI, 2.60-3.99) and 4.02 (95% CI, 3.34-4.84), respectively. Relative risks of DVT after age standardization when comparing European subjects with Maori, Pacific Island and Asian subjects, were 2.14 (95% CI, 1.72-2.66), 3.20 (95% CI, 2.46-4.17) and 4.75 (95% CI, 3.80-5.94), respectively. Indirect age standardization was used for comparison of the diagnosis of PE. The ratio between the calculated expected number of cases and the actual number of cases was 1.32 (95% CI, 0.89-1.75) for Maori subjects, 2.96 (95% CI, 1.89-4.03) for Pacific Islanders and 3.89 (95% CI, 3.00-4.78) for Asians. CONCLUSION: Europeans have a significantly higher incidence of VTE compared with Maori, Pacific Island and Asian populations.

Seizure predisposition after perinatal hypoxia: effects of subsequent age and of an epilepsy predisposing gene mutation.

PURPOSE: There is a gap in our knowledge of the factors that modulate the predisposition to seizures following perinatal hypoxia. Herein, we investigate in a mouse model the effects of two distinct factors: developmental stage after the occurrence of the perinatal insult, and the presence of a seizure predisposing mutation. METHODS: Effects of age: P6 (postnatal day 6) mouse pups were subjected to acute hypoxia down to 4% O2 over the course of 45 min. Seizure susceptibilities to flurothyl-induced seizures (single exposures) and to flurothyl kindling were determined at specific subsequent ages. Effects of mutation: Heterozygote mice, with deletion of one copy of the Kcn1a gene, subjected to P6 hypoxia were compared as adults to wild-type mice with respect to susceptibility to a single exposure to flurothyl and to the occurrence of spontaneous seizures as detected by hippocampal electroencephalography (EEG) and video recordings. KEY FINDINGS: Effects of age: As compared to controls, wild-type mice exposed to P6 hypoxia had a shortened seizure latency in response to a single flurothyl exposure at P50, but not at P7 or P28 (p < 0.04). In addition, perinatal hypoxia at P6 enhanced the rate of development of flurothyl kindling performed at P28-38 (p < 0.03), but not at P7-17. Effects of mutation: Kcn1a heterozygous mice subjected to P6 hypoxia exhibited increased susceptibility to flurothyl-induced seizures at P50 as compared to Normoxia heterozygote littermates, and to wild-type Hypoxia and Normoxia mice. In addition, heterozygotes exposed to P6 hypoxia were the only group in which spontaneous seizures were detected during the period of long-term monitoring (p < 0.027 in all comparisons). SIGNIFICANCE: Our data establish a mouse model of mild perinatal hypoxia in which we document the following: (1) the emergence, after a latent period, of increased susceptibility to flurothyl-induced seizures, and to flurothyl induced kindling; and (2) an additive effect of a gene mutation to the seizure predisposing consequences of perinatal hypoxia, thereby demonstrating that a modifier (or susceptibility) gene can exacerbate the long-term consequences of hypoxic injury.

Relative efficacy of micronutrient powders versus iron-folic acid tablets in controlling anemia in women in the second trimester of pregnancy.

BACKGROUND: Iron deficiency is a major cause of anemia and the most prevalent nutrient deficiency among pregnant women in developing countries. The use of iron and folic acid supplements to treat and prevent iron-deficiency anemia has limited effectiveness, mainly due to poor adherence. Home fortification with a micronutrient powder for pregnant women may be an effective and acceptable alternative to traditional drug models. OBJECTIVE: To determine whether home fortification with micronutrient powders is at least as efficacious as iron and folic acid tablets for improving hemoglobin concentration in pregnant women. METHODS: A cluster-randomized noninferiority trial was conducted in the rural subdistrict of Kaliganj in central Bangladesh. Pregnant women (gestational age 14-22 weeks, n=478), were recruited from 42 community-based Antenatal Care Centres. Each centre was randomly allocated to receive either a micronutrient powder (containing iron,folic acid, vitamin C, and zinc) or iron and folic acid tablets. Changes in hemoglobin from baseline were compared across groups using a linear mixed-effects regression model. RESULTS: At enrolment, the overall prevalence of anemia was 45% (n = 213/478). After the intervention period, the mean hemoglobin concentrations among women receiving the micronutrient powder were not inferior to those among women receiving tablets (109.5 ± 12.9 vs. 112.0 ± 11.2 g/L; 95% CI, -0.757 to 5.716). Adherence to the micronutrient powder was lower than adherence to tablets (57.5 ± 22.5% vs. 76.0 ± 13.7%; 95% CI, -22.39 to -12.94); however, in both groups, increased adherence was positively correlated with hemoglobin concentration. CONCLUSIONS: The micronutrient powder was at least as efficacious as the iron and folic acid tablets in controlling moderate to severe anemia during pregnancy.

How do we manage venous thromboembolism in pregnancy? A retrospective review of the practice of diagnosing and managing pregnancy-related venous thromboembolism at two major hospitals in Australia and New Zealand.

BACKGROUND: North American and European literature suggest that the incidence rate for pregnancy-related thromboembolism (VTE) ranges from 0.5 to 2 per 1000 pregnancies. However, there is a paucity of data regarding pregnancy-related VTE in Australia and New Zealand. AIMS: To define the epidemiology, management and adverse effects of pregnancy-related VTE in Australia and New Zealand. METHOD: Retrospective chart review of pregnant patients with objectively diagnosed pregnancy-related VTE at Monash Medical Centre and the North Shore Hospital from January 2007 to March 2011. RESULTS: Sixty women with VTE were identified, 31 and 29 in the antepartum and post-partum period respectively. VTE occurred as early as 8 weeks of gestation. There was a trend towards higher proportion of PE in the postpartum period. Most antenatal patients were started on enoxaparin and dosed according to weight at diagnosis. A wide variability in maintenance dosing strategies was observed. Three (5%, 95% CI: 1% to 14%) patients suffered major bleeds, all occurring post-partum. Recurrences occurred in two post-partum patients who received a truncated course of enoxaparin for distal deep-vein thrombosis. Although more women had an induction of labour, this did not translate into an increased Caesarean section rate. CONCLUSION: The epidemiology of pregnancy-related VTE is similar to that of other developed countries. All three bleeding events occurred in the immediate post-partum setting, highlighting the need for caution at this critical time. VTE recurrences occurred in those women with post-partum distal deep-vein thrombosis treated with an abbreviated course of enoxaparin.

An unusual case of spontaneous bladder perforation with associated autodialysis of the ensuing urinary ascites.

Spontaneous rupture of the urinary bladder is a rare occurrence, and when encountered it is a diagnostic challenge. We present an unusual case of urinary bladder rupture in a patient with severe cerebral palsy who initially presented with localized abdominal pain and during admission developed generalized peritonitis caused by bladder rupture. In this case, the patient had none of risk factors associated with urinary bladder.

An efficient algorithm for denoising MR and CT images using digital curvelet transform.

This chapter presents a curvelet-based approach for the denoising of magnetic resonance (MR) and computed tomography (CT) images. Curvelet transform is a new multiscale representation suited for objects which are smooth away from discontinuities across curves, which was developed by Candies and Donoho (Proceedings of Curves and Surfaces IV, France:105-121, 1999). We apply these digital transforms to the denoising of some standard MR and CT images embedded in white noise, random noise, and poisson noise. In the tests reported here, simple thresholding of the curvelet coefficients is very competitive with "state-of-the-art" techniques based on wavelet transform methods. Moreover, the curvelet reconstructions exhibit higher perceptual quality than wavelet-based reconstructions, offering visually sharper images and, in particular, higher quality recovery of edges and of faint linear and curvilinear features. Since medical images have several objects and curved shapes, it is expected that curvelet transform would be better in their denoising. The simulation results show the outperforms than wavelet transform in the denoising of both MR and CT images from both visual quality and the peak signal-to-noise (PSNR) ratio points of view.

Daily use of Sprinkles micronutrient powder for 2 months reduces anemia among children 6 to 36 months of age in the Kyrgyz Republic: a cluster-randomized trial.

BACKGROUND: Iron-deficiency anemia is widespread among young children in the Kyrgyz Republic, and there is an urgent need to identify an effective intervention to address this significant public health problem. OBJECTIVE: To test the effectiveness of a 2-month intervention with daily home fortification of complementary food using micronutrient powder (Sprinkles) in reducing anemia among children 6 to 36 months of age in the Kyrgyz Republic. METHODS: In this cluster-randomized, community-based effectiveness trial conducted in three regions of the Kyrgyz Republic, 24 clusters of children aged 6 to 36 months were randomly assigned to two groups. The intervention group (12 clusters, n = 1,103) received 60 sachets of micronutrient powder (12.5 mg elemental iron), which were taken as one sachet daily for 2 months. The control group (12 clusters, n = 1,090) did not receive micronutrient powder until after the study period. Blood hemoglobin concentration was assessed at the start and end of the intervention. RESULTS: From baseline to follow-up, the mean hemoglobin concentration in the intervention group increased by 7 g/L, whereas it decreased by 2 g/L in the control group (p < .001). The prevalence of anemia (hemoglobin < 110 g/L) in the intervention group decreased from 72% at baseline to 52% at follow-up, whereas it increased from 72% to 75% in the control group (p < .001). Compliance with the intervention was high, with children consuming on average 45 of the 60 sachets given. CONCLUSIONS: A course of 60 Sprinkles micronutrient powder sachets taken daily for 2 months is effective in improving hemoglobin levels and reducing the prevalence of anemia among young children in the Kyrgyz Republic.

Unexpectedly high early prevalence of anaemia in 6-month-old breast-fed infants in rural Bangladesh.

OBJECTIVE: To determine the prevalence of anaemia and maternal and infant factors associated with Hb values in infants at 6 months of age in rural Bangladesh. DESIGN: Infants (born to mothers supplemented with Fe-folic acid from mid-pregnancy) were visited at birth and 6 months of age. Mothers' anthropometric status, and infants' birth weight, gestational age at birth, weight and Hb concentration at 6 months were measured. Household socio-economic and demographic data, infant feeding practices and health status were collected using a pre-tested structured questionnaire. SETTING: Rural Bangladesh. SUBJECTS: Four hundred and two infants. RESULTS: For the total cohort (n 402), the range of anaemia prevalence values was from 30.6 % using a cut-off value of Hb < 95 g/l to 71.9 % using a value of Hb < 110 g/l. Birth weight and month of birth were the only factors positively associated with infant Hb in a linear regression model (P = 0.008 and 0.011, respectively). CONCLUSIONS: There was an unexpectedly high prevalence of anaemia in infants at 6 months of age, before the assumed period of vulnerability. Hb at this age tended to be higher in those with higher birth weight. We also found a season effect on Hb, as it tended to be higher as the study progressed. The high prevalence of anaemia at such an early age needs to be addressed to minimize the disease's long-term consequences.