Publications by authors named "Anum Minhas"

19 Publications

  • Page 1 of 1

Racial Disparities in Cardiovascular Complications With Pregnancy-Induced Hypertension in the United States.

Hypertension 2021 Jun 8:HYPERTENSIONAHA12117104. Epub 2021 Jun 8.

From the Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD (A.S.M., A.G.H., E.D.M.).

Women with pregnancy-induced hypertension, defined as gestational hypertension and preeclampsia/eclampsia, are at increased risk of long-term cardiovascular disease, but less is known about the spectrum of acute cardiovascular outcomes, especially across racial/ethnic groups. We evaluated the risk of cardiovascular events at delivery associated with gestational hypertension and preeclampsia/eclampsia, compared with no pregnancy-induced hypertension, overall and by race/ethnicity. We used the 2016 to 2018 National Inpatient Sample data. , , Clinical Modification codes identified delivery hospitalizations and clinical diagnoses. Using survey weights, cardiovascular events were examined using logistic regression by pregnancy-induced hypertension status, with subsequent stratification by race/ethnicity. Among 11 304 996 deliveries in 2016 to 2018, gestational hypertension occurred in 614 995 (5.4%) and preeclampsia in 593 516 (5.2%). Black women had higher odds for preeclampsia independent of underlying comorbidities (adjusted odds ratio, 1.45 [95% CI, 1.42-1.49]) and had the highest rates for several complications (peripartum cardiomyopathy, 506; heart failure, 660; acute renal failure, 953; and arrhythmias, 418 per 100 000 deliveries). After adjustment for socioeconomic factors and comorbidities, preeclampsia/eclampsia was associated with increased risk of cardiovascular events in women of all races/ethnicities. However, risk was highest among Asian/Pacific Islander women and lowest among Black women. In sum, while Black women were the most likely to experience preeclampsia, Asian/Pacific women were the most at risk for acute cardiovascular complications during delivery hospitalization.
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http://dx.doi.org/10.1161/HYPERTENSIONAHA.121.17104DOI Listing
June 2021

Association of Angiotensin Receptor Autoantibodies With Cardiovascular Abnormalities in Preeclampsia.

J Am Heart Assoc 2021 Jun 5;10(12):e020831. Epub 2021 Jun 5.

Division of Maternal-Fetal Medicine Department of Gynecology and Obstetrics Johns Hopkins University School of Medicine Baltimore MD.

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http://dx.doi.org/10.1161/JAHA.121.020831DOI Listing
June 2021

Left atrial function in patients with COVID-19 and its association with incident atrial fibrillation/flutter.

J Am Soc Echocardiogr 2021 May 31. Epub 2021 May 31.

Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA. Electronic address:

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http://dx.doi.org/10.1016/j.echo.2021.05.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8165042PMC
May 2021

Sex-Specific Plaque Signature: Uniqueness of Atherosclerosis in Women.

Curr Cardiol Rep 2021 Jun 3;23(7):84. Epub 2021 Jun 3.

Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, MD, USA.

Purpose Of Review: Cardiovascular disease is a leading cause of morbidity and mortality in both men and women, although there are notable differences in presentation between men and women. Atherosclerosis remains the predominant driver of coronary heart disease in both sexes; however, sex differences in atherosclerosis should be investigated further to understand clinical manifestations between men and women.

Recent Findings: There are sex differences in the prevalence, progression, and prognostic impact of atherosclerosis. Furthermore, developing evidence demonstrates unique differences in atherosclerotic plaque characteristics between men and women on both noninvasive and invasive imaging modalities. Coronary microvascular dysfunction may be present even if no obstructive lesions are found. Most importantly, non-obstructive coronary artery disease is associated with a heightened risk of future adverse cardiovascular events and should not be ignored. The distinct plaque signature in women should be recognized, and optimal preventive strategies should be performed for both sexes.
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http://dx.doi.org/10.1007/s11886-021-01513-3DOI Listing
June 2021

The role of sex and inflammation in cardiovascular outcomes and mortality in COVID-19.

Int J Cardiol 2021 May 8. Epub 2021 May 8.

Division of Cardiology, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA. Electronic address:

Objective: Higher mortality in COVID-19 in men compared to women is recognized, but sex differences in cardiovascular events are less well established. We aimed to determine the independent contribution of sex to stroke, myocardial infarction and death in the setting of COVID-19 infection.

Methods: We performed a retrospective cohort study of hospitalized COVID-19 patients in a racially/ethnically diverse population. Clinical features, laboratory markers and clinical events were initially abstracted from medical records, with subsequent clinician adjudication.

Results: Of 2060 patients, myocardial injury (32% vs 23%, p = 0.019), acute myocardial infarction (2.7% vs 1.6%, p = 0.114), and ischemic stroke (1.8% vs 0.7%, p = 0.007) were more common in men vs women. In-hospital death occurred in 160 men (15%) vs 117 women (12%, p = 0.091). Men had higher odds of myocardial injury (odds ratio (OR) 2.04 [95% CI 1.43-2.91], p < 0.001), myocardial infarction (1.72 [95% CI 0.93-3.20], p = 0.085) and ischemic stroke (2.76 [95% CI 1.29-5.92], p = 0.009). Despite adjustment for demographics and cardiovascular risk factors, male sex predicted mortality (HR 1.33; 95% CI:1.01-1.74; p = 0.041). While men had significantly higher markers of inflammation, in sex-stratified analyses, increase in interleukin-6, C-reactive protein, ferritin and d-dimer were predictive of mortality and myocardial injury similarly in both sexes.

Conclusions: Adjusted odds of myocardial injury, ischemic stroke and all-cause mortality, but not myocardial infarction, are significantly higher in men compared to women with COVID-19. Higher inflammatory markers are present in men but associated similarly with risk in both men and women. These data suggest that adverse cardiovascular outcomes in men vs. women are independent of cardiovascular comorbidities.
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http://dx.doi.org/10.1016/j.ijcard.2021.05.011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8106202PMC
May 2021

Multimodality Imaging for Cardiac Evaluation in Patients with COVID-19.

Curr Cardiol Rep 2021 03 15;23(5):44. Epub 2021 Mar 15.

Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, Carnegie 568, Baltimore, MD, 21287, USA.

Purpose Of Review: A growing number of cardiovascular manifestations resulting from the novel SARS-CoV-2 coronavirus (COVID-19) have been described since the beginning of this global pandemic. Acute myocardial injury is common in this population and is associated with higher rates of morbidity and mortality. The focus of this review centers on the recent applications of multimodality imaging in the diagnosis and management of COVID-19-related cardiovascular conditions.

Recent Findings: In addition to standard cardiac imaging techniques such as transthoracic echocardiography, other modalities including computed tomography and cardiac magnetic resonance imaging have emerged as useful adjuncts in select patients with COVID-19 infection, particularly those with suspected ischemic and nonischemic myocardial injury. Data have also emerged suggesting lasting COVID-19 subclinical cardiac effects, which may have long-term prognostic implications. With the spectrum of COVID-19 cardiovascular manifestations observed thus far, it is important for clinicians to recognize the role, strengths, and limitations of multimodality imaging techniques in this patient population.
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http://dx.doi.org/10.1007/s11886-021-01483-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7957471PMC
March 2021

Prominent Longitudinal Strain Reduction of Basal Left Ventricular Segments in Patients With Coronavirus Disease-19.

J Card Fail 2021 01 28;27(1):100-104. Epub 2020 Sep 28.

Division of Cardiology, Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, Maryland. Electronic address:

Background: Coronavirus disease-19 (COVID-19) has been associated with overt and subclinical myocardial dysfunction. We observed a recurring pattern of reduced basal left ventricular (LV) longitudinal strain on speckle-tracking echocardiography in hospitalized patients with COVID-19 and subsequently aimed to identify characteristics of affected patients. We hypothesized that patients with COVID-19 with reduced basal LV strain would demonstrate elevated cardiac biomarkers.

Methods And Result: Eighty-one consecutive patients with COVID-19 underwent speckle-tracking echocardiography. Those with poor quality speckle-tracking echocardiography (n = 2) or a known LV ejection fraction of <50% (n = 4) were excluded. Patients with an absolute value basal longitudinal strain of <13.9% (2 standard deviations below normal) were designated as cases (n = 39); those with a basal longitudinal strain of ≥13.9% were designated as controls (n = 36). Demographics and clinical variables were compared. Of 75 included patients (mean age 62 ± 14 years, 41% women), 52% had reduced basal strain. Cases had higher body mass index (median 34.1; interquartile range 26.5-37.9 kg/m vs median 26.9, interquartile range, 24.8-30.0 kg/m, P = .009), and greater proportions of Black (74% vs 36%, P = .0009), hypertensive (79% vs 56%, P = .026), and diabetic patients (44% vs 19%, P = .025) compared with controls. Troponin and N-terminal pro-brain natriuretic peptide levels trended higher in cases, but were not significantly different.

Conclusions: Reduced basal LV strain is common in patients with COVID-19. Patients with hypertension, diabetes, obesity, and Black race were more likely to have reduced basal strain. Further investigation into the significance of this strain pattern is warranted.
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http://dx.doi.org/10.1016/j.cardfail.2020.09.469DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7521413PMC
January 2021

Takotsubo Syndrome in the Setting of COVID-19.

JACC Case Rep 2020 Jul 1;2(9):1321-1325. Epub 2020 May 1.

Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland.

A 58-year-old woman was admitted with symptoms of coronavirus disease-2019. She subsequently developed mixed shock, and an echocardiogram showed mid-distal left ventricular hypokinesis and apical ballooning, findings typical of stress, or takotsubo, cardiomyopathy. Over the next few days her left ventricular function improved, the further supporting the reversibility of acute stress cardiomyopathy. ().
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http://dx.doi.org/10.1016/j.jaccas.2020.04.023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7194596PMC
July 2020

Cardiac Device Clinical Trials: Where Are the Women and What Are Their Outcomes?

J Womens Health (Larchmt) 2020 10 30;29(10):1235-1236. Epub 2020 Apr 30.

Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.

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http://dx.doi.org/10.1089/jwh.2020.8456DOI Listing
October 2020

Patient Preferences for Coronary CT Angiography with Stress Perfusion, SPECT, or Invasive Coronary Angiography.

Radiology 2019 05 19;291(2):340-348. Epub 2019 Mar 19.

From the Department of Cardiology, Johns Hopkins Hospital and Health System, Baltimore, Md (A.M., A.L.V., M.R.O., M.M., C.C., P.M.); Departments of Radiology (M.D., M.L., M.R., S.F., M.P.) and Anesthesiology (E.S.), Charité-Universitätsmedizin Berlin, Humboldt-Universität and Freie Universität zu Berlin, Schumannstr 20/21, Berlin 10117, Germany; Department of Radiology, Keio University School of Medicine, Tokyo, Japan (Y.T.); Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil (C.E.R.); Department of Medicine, Division of Cardiology, St Luke's International Hospital, Tokyo, Japan (H.N.); Department of Cardiology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark (K.F.K.); Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands (J.G.); Department of Radiology, Mount Elizabeth Hospital, Singapore (J.H.); Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Md (M.Y.C.); Department of Radiology, Mie University Hospital, Tsu, Japan (K.K.); Department of Radiology, Albert Einstein Hospital, São Paulo, Brazil (C.N.); Department of Radiology, Beth Israel Deaconess Medical Center, Harvard University, Boston, Mass (M.E.C.); Department of Radiology, University of Ottawa Faculty of Medicine, Ottawa, Canada (F.J.R.); Department of Cardiology, National Heart Center Singapore, Singapore (S.Y.T.); and Department of Radiology, Toronto General Hospital, Toronto, Canada (N.P.).

Background Patient preference is pivotal for widespread adoption of tests in clinical practice. Patient preferences for invasive versus other noninvasive tests for coronary artery disease are not known. Purpose To compare patient acceptance and preferences for noninvasive and invasive cardiac imaging in North and South America, Asia, and Europe. Materials and Methods This was a prospective 16-center trial in 381 study participants undergoing coronary CT angiography with stress perfusion, SPECT, and invasive coronary angiography (ICA). Patient preferences were collected by using a previously validated questionnaire translated into eight languages. Responses were converted to ordinal scales and were modeled with generalized linear mixed models. Results In patients in whom at least one test was associated with pain, CT and SPECT showed reduced median pain levels, reported on 0-100 visual analog scales, from 20 for ICA (interquartile range [IQR], 4-50) to 6 for CT (IQR, 0-27.5) and 5 for SPECT (IQR, 0-25) ( < .001). Patients from Asia reported significantly more pain than patients from other continents for ICA (median, 25; IQR, 10-50; = .01), CT (median, 10; IQR, 0-30; = .02), and SPECT (median, 7; IQR, 0-28; = .03). Satisfaction with preparation differed by continent and test ( = .01), with patients from Asia reporting generally lower ratings. Patients from North America had greater percentages of "very high" or "high" satisfaction than patients from other continents for ICA (96% vs 82%, respectively; < .001) and SPECT (95% vs 79%, respectively; = .04) but not for CT (89% vs 86%, respectively; = .70). Among all patients, CT was preferred by 54% of patients, compared with 18% for SPECT and 28% for ICA ( < .001). Conclusion For cardiac imaging, patients generally favored CT angiography with stress perfusion, while study participants from Asia generally reported lowest satisfaction. © RSNA, 2019 See also the editorial by Woodard and Nguyen in this issue.
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http://dx.doi.org/10.1148/radiol.2019181409DOI Listing
May 2019

Syncope With Unusual Wide Complex Arrhythmia in a Young Woman.

Circulation 2018 11;138(20):2289-2292

Division of Cardiology, The Johns Hopkins University School of Medicine, Baltimore, MD.

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http://dx.doi.org/10.1161/CIRCULATIONAHA.118.037346DOI Listing
November 2018

Iterative Reconstruction Results in Larger Computed Tomography Measurements of Iliofemoral Artery Diameter in Patients Referred for Transcatheter Aortic Valve Replacement.

J Comput Assist Tomogr 2016 Sep-Oct;40(5):773-6

From the Departments of *Medicine and †Radiology, University of Michigan, Ann Arbor, MI; and ‡Department of Anesthesiology, Cedars-Sinai Medical Center, Los Angeles, CA.

Objectives: We hypothesized that improved iterative reconstruction increases image quality and reduces artifacts for iliofemoral artery computed tomography imaging in patients referred for transcatheter aortic valve replacement (TAVR).

Methods: We examined 56 consecutive patients undergoing computed tomography for possible TAVR and compared image quality and iliofemoral artery size between adaptive statistical iterative reconstructions (ASIRs) and improved model-based iterative reconstructions (MBIRs).

Results: Model-based iterative reconstruction (vs ASIR) was associated with improved (P < 0.001 for each) image quality (3.4 ± 0.8 vs 2.8 ± 1.0), beam hardening (3.5 ± 0.8 vs 3.0 ± 1.1), and wall definition (3.6 ± 0.6 vs 3.1 ± 0.8). Image signal-to-noise ratios (20.4 ± 10.1 vs 13.7 ± 6.6, P < 0.001) were also increased with MBIR as compared with ASIR. Mean iliofemoral artery size was larger using MBIR compared with ASIR (left, 7.7 ± 1.5 vs 7.4 ± 1.7 mm, P < 0.001; right, 7.8 ± 1.2 vs 7.4 ± 1.5 mm, P = 0.008).

Conclusions: In patients referred for TAVR, improved MBIR resulted in higher image quality, reduced artifacts, and larger iliofemoral artery diameters compared with standard iterative reconstructions.
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http://dx.doi.org/10.1097/RCT.0000000000000421DOI Listing
January 2017

Renal function in atrial fibrillation patients switched from warfarin to a direct oral anticoagulant.

J Thromb Thrombolysis 2016 Nov;42(4):566-72

Frankel Cardiovascular Center, University of Michigan Medical Center, Ann Arbor, MI, USA.

All available direct oral anticoagulants (DOACs) are at least partially eliminated by the kidneys. These agents are increasingly being used as alternatives to warfarin for stroke prevention in patients with atrial fibrillation. The aim of this study was to identify changes in renal function and associated DOAC dosing implications in a multicenter cohort of atrial fibrillation patients switched from warfarin to DOAC treatment. We included all patients in the Michigan Anticoagulation Quality Improvement Initiative cohort who switched from warfarin to a DOAC with atrial fibrillation as their anticoagulant indication between 2009 and 2014, and who had at least two creatinine values. Compliance with FDA-recommended dosing based on renal function was assessed. Of the 189 patients switched from warfarin to a DOAC, 34 (18.0 %) had a baseline creatinine clearance <50 mL/min and 23 (12.2 %) experienced important fluctuations in renal function. Of these 23 patients, 6 (26.1 %) should have impacted the DOAC dosing, but only 1 patient actually received an appropriate dose adjustment. Additionally, 15 (7.9 %) of patients on DOACs had a dose change performed, but only one patient demonstrated a change in renal function to justify the dose adjustment. Most atrial fibrillation patients who switched from warfarin to a DOAC had stable renal function. However, the majority of patients who had a change in renal function did not receive the indicated dose change. As the use of DOACs expands, monitoring of renal function and appropriate dose adjustments are critical.
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http://dx.doi.org/10.1007/s11239-016-1377-9DOI Listing
November 2016

Nationwide Trends in Reported Incidence of Takotsubo Cardiomyopathy from 2006 to 2012.

Am J Cardiol 2015 Oct 15;116(7):1128-31. Epub 2015 Jul 15.

Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan.

Takotsubo cardiomyopathy (TC) is believed to be an increasingly diagnosed syndrome; however, data on its incidence are limited. The purpose of this study was to determine the reported incidence of TC in the United States and to examine its trend over several years. Data was obtained from the Nationwide Inpatient Sample, created by the Agency for Healthcare Research and Quality, for each of the years from 2006 to 2012. Hospital discharges with principal diagnosis of TC, identified using Internal Classification of Diseases, Ninth Revision, code 429.83, were included. We tabulated estimated total numbers of discharges, incidence per 100,000 persons, mean length of stay, inhospital death rates, and diagnoses stratified by age group and gender. The reported incidence of TC based on principal diagnosis at hospital discharge increased significantly over the study period, with 315 cases ± 43 (standard error) in 2006 and 6,230 cases ± 232 (standard error) in 2012 (p <0.001 for trend). Mean length of hospital stay was stable over the study period (3.4 days in 2006 vs 3.6 days in 2012; p = 0.74 for trend). The diagnosis was most frequent in patients aged 65 to 84 years (50% of all diagnoses in 2012), followed by those aged 45 to 64 years (39% of all diagnoses in 2012). Women accounted for >90% of diagnoses throughout the study period. In conclusion, the reported incidence of TC has increased significantly from 2006 to 2012, most likely because of increasing recognition of the syndrome.
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http://dx.doi.org/10.1016/j.amjcard.2015.06.042DOI Listing
October 2015

The development of a population of 4D pediatric XCAT phantoms for imaging research and optimization.

Med Phys 2015 Aug;42(8):4719-26

Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705.

Purpose: We previously developed a set of highly detailed 4D reference pediatric extended cardiac-torso (XCAT) phantoms at ages of newborn, 1, 5, 10, and 15 yr with organ and tissue masses matched to ICRP Publication 89 values. In this work, we extended this reference set to a series of 64 pediatric phantoms of varying age and height and body mass percentiles representative of the public at large. The models will provide a library of pediatric phantoms for optimizing pediatric imaging protocols.

Methods: High resolution positron emission tomography-computed tomography data obtained from the Duke University database were reviewed by a practicing experienced radiologist for anatomic regularity. The CT portion of the data was then segmented with manual and semiautomatic methods to form a target model defined using nonuniform rational B-spline surfaces. A multichannel large deformation diffeomorphic metric mapping algorithm was used to calculate the transform from the best age matching pediatric XCAT reference phantom to the patient target. The transform was used to complete the target, filling in the nonsegmented structures and defining models for the cardiac and respiratory motions. The complete phantoms, consisting of thousands of structures, were then manually inspected for anatomical accuracy. The mass for each major tissue was calculated and compared to linearly interpolated ICRP values for different ages.

Results: Sixty four new pediatric phantoms were created in this manner. Each model contains the same level of detail as the original XCAT reference phantoms and also includes parameterized models for the cardiac and respiratory motions. For the phantoms that were 10 yr old and younger, we included both sets of reproductive organs. This gave them the capability to simulate both male and female anatomy. With this, the population can be expanded to 92. Wide anatomical variation was clearly seen amongst the phantom models, both in organ shape and size, even for models of the same age and sex. The phantoms can be combined with existing simulation packages to generate realistic pediatric imaging data from different modalities.

Conclusions: This work provides a large cohort of highly detailed pediatric phantoms with 4D capabilities of varying age, height, and body mass. The population of phantoms will provide a vital tool with which to optimize 3D and 4D pediatric imaging devices and techniques in terms of image quality and radiation-absorbed dose.
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http://dx.doi.org/10.1118/1.4926847DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4506297PMC
August 2015

A set of 4D pediatric XCAT reference phantoms for multimodality research.

Med Phys 2014 Mar;41(3):033701

Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705.

Purpose: The authors previously developed an adult population of 4D extended cardiac-torso (XCAT) phantoms for multimodality imaging research. In this work, the authors develop a reference set of 4D pediatric XCAT phantoms consisting of male and female anatomies at ages of newborn, 1, 5, 10, and 15 years. These models will serve as the foundation from which the authors will create a vast population of pediatric phantoms for optimizing pediatric CT imaging protocols.

Methods: Each phantom was based on a unique set of CT data from a normal patient obtained from the Duke University database. The datasets were selected to best match the reference values for height and weight for the different ages and genders according to ICRP Publication 89. The major organs and structures were segmented from the CT data and used to create an initial pediatric model defined using nonuniform rational B-spline surfaces. The CT data covered the entire torso and part of the head. To complete the body, the authors manually added on the top of the head and the arms and legs using scaled versions of the XCAT adult models or additional models created from cadaver data. A multichannel large deformation diffeomorphic metric mapping algorithm was then used to calculate the transform from a template XCAT phantom (male or female 50th percentile adult) to the target pediatric model. The transform was applied to the template XCAT to fill in any unsegmented structures within the target phantom and to implement the 4D cardiac and respiratory models in the new anatomy. The masses of the organs in each phantom were matched to the reference values given in ICRP Publication 89. The new reference models were checked for anatomical accuracy via visual inspection.

Results: The authors created a set of ten pediatric reference phantoms that have the same level of detail and functionality as the original XCAT phantom adults. Each consists of thousands of anatomical structures and includes parameterized models for the cardiac and respiratory motions. Based on patient data, the phantoms capture the anatomic variations of childhood, such as the development of bone in the skull, pelvis, and long bones, and the growth of the vertebrae and organs. The phantoms can be combined with existing simulation packages to generate realistic pediatric imaging data from different modalities.

Conclusions: The development of patient-derived pediatric computational phantoms is useful in providing variable anatomies for simulation. Future work will expand this ten-phantom base to a host of pediatric phantoms representative of the public at large. This can provide a means to evaluate and improve pediatric imaging devices and to optimize CT protocols in terms of image quality and radiation dose.
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http://dx.doi.org/10.1118/1.4864238DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3987726PMC
March 2014

Compendium of resources for radiation safety in medical imaging using ionizing radiation.

J Am Coll Radiol 2013 May 28;10(5):354-60, 360.e1-2. Epub 2013 Mar 28.

Duke University School of Medicine, Durham, North Carolina, USA.

Purpose: Diagnostic imaging, including ionizing radiation modalities, maintains a prominent role in the medical evaluation of patients. There is increasing awareness and need for information across varied sectors about low-level radiation and potential risks. Many medical and scientific organizations have resources discussing radiation risk and management. However, there is no single resource compiling this information.

Methods: Websites, including those of national and international medical organizations, were reviewed for information on radiation dose, risk, justification, optimization, guidelines (including general information about improvement in quality and dose reduction without specific mention of optimization techniques), appropriateness criteria, and general principles of radiation safety for CT, fluoroscopy or angiography, and radiography. This information was organized into 8 tables, categorized by modality, and separated for adult and pediatric populations. Websites with training modules were noted as well.

Results: Twenty-nine websites were explored. Overall, less information is available about medical radiation safety in children compared with adults. Across both groups, most information is available on CT, then fluoroscopy, and finally radiography. Across all groups and modalities, there is no information available for patients or parents on optimization, appropriateness, or guidelines, with the exception of adult radiography, for which there are some guidelines.

Conclusions: This compendium serves as a collective resource for communities including the public and regulatory organizations. Additionally, the compendium can be used to determine redundant or deficient areas, providing opportunities for more comprehensive resources and efficient efforts in accessing medical radiation patient safety information.
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http://dx.doi.org/10.1016/j.jacr.2012.10.005DOI Listing
May 2013

Pediatric Hodgkin lymphoma survivors at negligible risk for significant bone mineral density deficits.

Pediatr Blood Cancer 2009 Apr;52(4):516-21

Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee 38105-2794, USA.

Background: We hypothesized that pediatric Hodgkin lymphoma (HL) survivors would have bone mineral density (BMD) deficits compared to their peers because of osteotoxic chemotherapy during the time of greatest BMD accretion.

Methods: We retrospectively reviewed records of HL survivors returning for follow-up between 1990 and 2002. Of the 133 eligible survivors, 109 who underwent quantitative computed tomography (QCT) comprised the study group. QCT-determined BMD Z-scores were correlated with patient characteristics and therapeutic exposures by Wilcoxon rank sum or Chi-square tests. Logistic regression models were used to explore risk factors for diminished BMD.

Results: The study cohort was half male (50.5%) and 85.3% reported their race as white. Participants were representative of all survivors potentially eligible for study, except that more study participants were female, had hypothyroidism, and had received cyclophosphamide. Median age at diagnosis was 15.1 years (range, 3.1-20.7 years); median time between diagnosis and QCT was 7.5 years (range, 5.0-12.4 years). The proportion of HL survivors with BMD below the mean did not significantly differ from the general population (P = 0.503). However, those with BMD -1.5 SD and BMD -2.0 SD or lower (14.7% and 7.3%, respectively) exceeded that in the general population (6.7% and 2.3%, respectively; P < 0.001 for both degrees of severity). Males, diagnosed at 14 years or older, were at 6.5 times higher risk than females (OR 95% CI: 1.24-34.14; P = 0.027) for BMD deficits.

Conclusions: Overall, pediatric HL survivors had negligible BMD deficits. Male gender was associated with an increased risk of developing BMD deficits.
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http://dx.doi.org/10.1002/pbc.21908DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2730723PMC
April 2009