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1.
Abdom Radiol (NY) ; 45(8): 2370-2377, 2020 08.
Article in English | MEDLINE | ID: mdl-32333072

ABSTRACT

PURPOSE: To evaluate feasibility of a wide detector liver CT protocol with three acquisitions in the hepatic arterial phase. METHODS: Forty-one patients with cirrhosis prospectively underwent a wide detector axial liver CT protocol. Three 16 cm axial liver acquisitions were obtained during a single breath hold at peak aortic enhancement plus 10, 20, and 25 s. Two readers working separately scored overall exam quality, identified hyperenhancing lesions, and subjectively scored and ranked relative lesion conspicuity. Objective lesion enhancement was measured and CNR calculated. Data were analyzed using a generalized linear models and Tukey's post hoc testing. RESULTS: Seventy-one hyperenhancing lesions were identified with average size of 1.8 cm (range 0.4-9.6 cm). The two readers separately identified 60 and 54 lesions on the 10 s arterial acquisition, 70 and 67 on the 20 s, and 52 and 51 on the 25 s. The readers determined all exams had diagnostic image quality. Subjective ranking of lesion conspicuity was greatest at 20 s in 62% of lesions but was greatest at 10 or 25 s in 38%. CNR was highest at 20 s in 58% of lesions but was highest at 10 or 25 s in 42%. Overall, there was no significant difference in mean CNR between the three arterial acquisitions. CONCLUSION: A wide detector axial liver CT protocol with three acquisitions in the hepatic arterial phase is technologically feasible and results in diagnostic image quality. With this protocol, peak subjective and objective hyperenhancing lesion conspicuity may be earlier or later than 20 s in up to 40% of lesions.


Subject(s)
Liver Neoplasms , Radiographic Image Interpretation, Computer-Assisted , Contrast Media , Feasibility Studies , Humans , Liver Cirrhosis/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Tomography, X-Ray Computed
2.
AJR Am J Roentgenol ; 212(1): 117-123, 2019 01.
Article in English | MEDLINE | ID: mdl-30422713

ABSTRACT

OBJECTIVE: The purpose of this study was to compare dual-energy CT (DECT) urography with a 50% reduced iodine dose to single-energy CT (SECT) urography with a standard iodine dose with respect to attenuation of renal vascular and urinary tract structures and with respect to image quality. SUBJECTS AND METHODS: The study included 62 patients undergoing evaluation of urinary tract lithiasis, tumor, or hematuria. Thirty-one patients underwent DECT urography with a 50% reduced iodine dose and reconstruction at 50 and 77 keV. These subjects were sex, age, and size matched to a group of 31 patients who underwent 120-kVp SECT urography with a standard iodine dose. The mean iodine dose was 22 g for DECT and 44 g for SECT. Attenuation was measured at seven locations in the renal arteries, renal veins, and urinary tract. Two reviewers subjectively scored the image quality parameters image noise, sharpness of urinary tract contours, enhancement of urinary structures, and streak artifacts. RESULTS: Mean DECT attenuation at 50 keV was the same as or greater than SECT attenuation at each of the seven locations. Measured image noise was highest at 50-keV DECT but was the same for 77-keV DECT and 120-kVp SECT. Mean subjective scores for DECT image quality parameters were the same as or higher than those of SECT, except for streak artifact and sharpness of urinary tract contours. CONCLUSION: DECT urography with a 50% reduced iodine dose may result in measured renal vascular and urinary tract attenuation the same as or higher than and image quality measurements and scores similar to those obtained with 120-kVp SECT urography with a standard iodine dose.


Subject(s)
Contrast Media/administration & dosage , Iohexol/administration & dosage , Radiography, Dual-Energy Scanned Projection/methods , Tomography, X-Ray Computed/methods , Triiodobenzoic Acids/administration & dosage , Urography/methods , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Radiographic Image Interpretation, Computer-Assisted
3.
Abdom Radiol (NY) ; 42(3): 759-765, 2017 03.
Article in English | MEDLINE | ID: mdl-28084544

ABSTRACT

PURPOSE: To compare dual-energy computed tomography (DECT) aortography using a 70% reduced iodine dose to single-energy CT (SECT) aortography using a standard iodine dose in the same patient. METHODS: Twenty-one patients with a prior SECT aortography using standard iodine dose had DECT aortography using 70% reduced iodine dose. Section 120 kVp images were compared to DECT images reconstructed at both 50 and 77 keV. Reviewers measured image noise and attenuation in the aorta at eight locations from proximal to distal and subjectively scored vascular enhancement on a four-point scale. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. The volume CT dose index (CTDIvol) for each exam was recorded. RESULTS: Mean iodine dose was 50 g for SECT and 15 g for DECT (70% reduction). Mean aortic attenuation was similar for section 120 kVp (350 ± 67 HU) and DECT 50 keV (338 ± 57 HU, p = 0.547) but was lower at 77 keV (152 ± 23 HU). Measured image noise was greatest at 50 keV (12 ± 5 HU) and was lowest at 77 keV (7 ± 2 HU, p > 0.001). There was no difference in SNR or CNR between 120 kVp and 50 keV (p > 0.05). Mean subjective vascular enhancement scores for SECT were between good and excellent (3.33-3.69), and for DECT at 50 keV were between moderate and good (2.54-2.93, p < 0.0001). CTDIvol was 13.6 mGy for SECT and 13.1 mGy for DECT (p = 0.637). CONCLUSION: 70% Reduced iodine DECT aortography may result in similar aortic attenuation, CNR, SNR, and lower although acceptable subjective image scores when compared to standard iodine SECT aortography in the same patient.


Subject(s)
Aortic Aneurysm/diagnostic imaging , Computed Tomography Angiography/methods , Contrast Media/administration & dosage , Iohexol/administration & dosage , Triiodobenzoic Acids/administration & dosage , Aged , Aortic Aneurysm/surgery , Female , Humans , Male , Middle Aged , Prospective Studies , Radiographic Image Interpretation, Computer-Assisted , Radiography, Dual-Energy Scanned Projection , Signal-To-Noise Ratio
4.
Clin Imaging ; 40(6): 1213-1218, 2016.
Article in English | MEDLINE | ID: mdl-27616154

ABSTRACT

PURPOSE: This study aims to compare transcatheter aortic valve replacement (TAVR) planning on 16 cm wide-detector computed tomography (CT) to TAVR planning on 4 cm detector CT. MATERIALS AND METHODS: A total of 36 patients who had TAVR planning axial CT on a wide-detector scanner (protocol 1) were compared to 36 patients who had helical 4 cm detector CT (protocol 2). RESULTS: Vascular attenuation was greater for protocol 1, but image noise, contrast-to-noise ratio, and signal-to-noise ratio were the same. Radiation dose was lower and iodine dose was less for protocol 1. CONCLUSION: Protocol 1 had greater vascular attenuation and similar image quality but lower radiation and less iodine compared to protocol 2.


Subject(s)
Contrast Media/administration & dosage , Image Enhancement , Iodine/administration & dosage , Radiation Dosage , Tomography, Spiral Computed/methods , Tomography, X-Ray Computed/methods , Transcatheter Aortic Valve Replacement , Aged , Female , Humans , Male , Retrospective Studies , Signal-To-Noise Ratio
5.
Acad Radiol ; 23(5): 611-8, 2016 May.
Article in English | MEDLINE | ID: mdl-26897602

ABSTRACT

RATIONALE AND OBJECTIVES: Because many patients with aortic pathology also have compromised renal function, we wished to investigate dual-energy computed tomography (DECT) aortography with 50% reduced iodine dose compared to single-energy computed tomography (SECT) aortography with standard iodine dose. MATERIALS AND METHODS: Fifty patients had DECT aortography with 50% reduced iodine dose. Thirty-four of these patients had prior SECT aortography with standard iodine dose. DECT images were reconstructed at both 50 and 77 keV and were compared to SECT 120 kVp images. Reviewers measured aortic attenuation, image noise, and scored vascular enhancement. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were calculated. Volume CT dose index was recorded. RESULTS: Mean iodine dose was 47 g for SECT and 24 g for DECT. Aortic attenuation was highest at reduced iodine dose DECT 50 keV (570 ± 105 Hounsfield units [HU]) compared to 77 keV (239 ± 40 HU) or to standard iodine dose SECT 120 kVp (356 ± 69 HU) (P < 0.05). Image noise was greatest at 50 keV compared to 77 keV and 120 kVp (P < 0.05) but was similar between 77 keV and 120 kVp (P > 0.05). SNR and CNR were the same at 50 keV and 120 kVp (P > 0.05). Mean vascular enhancement scores were all above 3.0 (good, typical enhancement). Volume CT dose index was 11.7 mGy for DECT and 11.8 mGy for SECT (P = 0.37). CONCLUSIONS: DECT aortography with 50% reduced iodine reconstructed at 50 keV resulted in significantly greater aortic attenuation, good subjective vascular enhancement, and comparable SNR and CNR compared to standard iodine dose SECT. DECT image noise at 77 keV was similar to SECT at 120 kVp.


Subject(s)
Aortography/methods , Computed Tomography Angiography/methods , Contrast Media/administration & dosage , Iodine/administration & dosage , Radiation Dosage , Radiography, Dual-Energy Scanned Projection/methods , Aged , Aged, 80 and over , Aorta/diagnostic imaging , Female , Humans , Image Processing, Computer-Assisted/methods , Iohexol/administration & dosage , Male , Middle Aged , Prospective Studies , Radiographic Image Enhancement/methods , Signal-To-Noise Ratio , Triiodobenzoic Acids/administration & dosage
6.
AJR Am J Roentgenol ; 203(3): 601-6, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25148163

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the effect of use of dual-energy CT monochromatic imaging in the late hepatic arterial phase on hyperenhancing focal lesion detection and lesion conspicuity. SUBJECTS AND METHODS: This prospective study included 72 patients imaged with a single-source dual-energy CT scanner. Late arterial phase imaging was performed with dual energies of 140 and 80 kVp, and the portal venous and delayed phases were performed with a single energy of 120 kVp. Two deidentified image sets were created: set A consisted of 77-keV images only, and set B consisted of 40-, 50-, 70-, and 77-keV images and iodine-based contrast material decomposition images. Two independent reviewers identified hypervascular lesions and subjectively scored lesion conspicuity. Contrast-to-noise ratios were calculated, and radiation dose (volume CT dose index) was recorded. RESULTS: The 128 lesions identified had a mean size of 1.7 ± 1.4 cm. There was no difference in lesion detection between the two reviewers or the two image sets. The contrast-to-noise ratio at 50 keV was 72% greater than that at 77 keV (p < 0.0001). Subjective conspicuity was statistically greatest at 50 keV (p < 0.0001). There was no statistical difference in mean volume CT dose index between the dual-energy (12.8 mGy) and the two single-energy (14.4 and 14.2 mGy) phases. CONCLUSION: Viewing dual-energy CT images may result in the greatest subjective lesion conspicuity and measured contrast-to-noise ratio at 50 keV with equal detection of hyperenhancing liver lesions compared with viewing 77-keV images alone. In addition, the radiation doses of dual-energy CT may be similar to those of single-energy CT.


Subject(s)
Liver Cirrhosis/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Neovascularization, Pathologic/diagnostic imaging , Precancerous Conditions/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted/methods , Radiography, Dual-Energy Scanned Projection/methods , Female , Humans , Liver Cirrhosis/complications , Liver Neoplasms/blood supply , Liver Neoplasms/etiology , Male , Middle Aged , Neovascularization, Pathologic/etiology , Observer Variation , Portal Vein/diagnostic imaging , Radiographic Image Enhancement/methods , Reproducibility of Results , Sensitivity and Specificity , Signal-To-Noise Ratio , Tomography, X-Ray Computed/methods
7.
Radiology ; 273(3): 793-800, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25170546

ABSTRACT

PURPOSE: To investigate whether reduced radiation dose liver computed tomography (CT) images reconstructed with model-based iterative reconstruction ( MBIR model-based iterative reconstruction ) might compromise depiction of clinically relevant findings or might have decreased image quality when compared with clinical standard radiation dose CT images reconstructed with adaptive statistical iterative reconstruction ( ASIR adaptive statistical iterative reconstruction ). MATERIALS AND METHODS: With institutional review board approval, informed consent, and HIPAA compliance, 50 patients (39 men, 11 women) were prospectively included who underwent liver CT. After a portal venous pass with ASIR adaptive statistical iterative reconstruction images, a 60% reduced radiation dose pass was added with MBIR model-based iterative reconstruction images. One reviewer scored ASIR adaptive statistical iterative reconstruction image quality and marked findings. Two additional independent reviewers noted whether marked findings were present on MBIR model-based iterative reconstruction images and assigned scores for relative conspicuity, spatial resolution, image noise, and image quality. Liver and aorta Hounsfield units and image noise were measured. Volume CT dose index and size-specific dose estimate ( SSDE size-specific dose estimate ) were recorded. Qualitative reviewer scores were summarized. Formal statistical inference for signal-to-noise ratio ( SNR signal-to-noise ratio ), contrast-to-noise ratio ( CNR contrast-to-noise ratio ), volume CT dose index, and SSDE size-specific dose estimate was made (paired t tests), with Bonferroni adjustment. RESULTS: Two independent reviewers identified all 136 ASIR adaptive statistical iterative reconstruction image findings (n = 272) on MBIR model-based iterative reconstruction images, scoring them as equal or better for conspicuity, spatial resolution, and image noise in 94.1% (256 of 272), 96.7% (263 of 272), and 99.3% (270 of 272), respectively. In 50 image sets, two reviewers (n = 100) scored overall image quality as sufficient or good with MBIR model-based iterative reconstruction in 99% (99 of 100). Liver SNR signal-to-noise ratio was significantly greater for MBIR model-based iterative reconstruction (10.8 ± 2.5 [standard deviation] vs 7.7 ± 1.4, P < .001); there was no difference for CNR contrast-to-noise ratio (2.5 ± 1.4 vs 2.4 ± 1.4, P = .45). For ASIR adaptive statistical iterative reconstruction and MBIR model-based iterative reconstruction , respectively, volume CT dose index was 15.2 mGy ± 7.6 versus 6.2 mGy ± 3.6; SSDE size-specific dose estimate was 16.4 mGy ± 6.6 versus 6.7 mGy ± 3.1 (P < .001). CONCLUSION: Liver CT images reconstructed with MBIR model-based iterative reconstruction may allow up to 59% radiation dose reduction compared with the dose with ASIR adaptive statistical iterative reconstruction , without compromising depiction of findings or image quality.


Subject(s)
Liver Diseases/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed , Adult , Contrast Media , Female , Humans , Iohexol , Male , Prospective Studies , Radiation Dosage , Reproducibility of Results , Signal-To-Noise Ratio
8.
J Child Adolesc Psychopharmacol ; 24(2): 83-9, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24506790

ABSTRACT

OBJECTIVE: The purpose of this study was to investigate the side effect risks from using one or more psychiatric medications (including antipsychotics, antidepressants, α-2 agonists, benzodiazepines, mood stabilizers, and stimulants) among a national cohort of children and adolescents. METHODS: A questionnaire survey was administered to parents who filled a prescription for a psychiatric medication for their child at a large national retail pharmacy chain. Primary outcome variables were the total count of side effects from a list of 12 problem areas, as well as parent-reported side effect intensity (mild/moderate/severe). Modifiers investigated included specific medication and number of medications utilized, demographics, and difficulties with access to care. RESULTS: A total of 1347 parents of study subjects ages 3-17 years from 30 U.S. states who were taking psychiatric medications for any indication purchased at one retail pharmacy chain enrolled following a single mail invitation (7.5% response). Of the study subjects, 80% were white/non-Hispanic, 64% were male, 63% had private health insurance, and 67% had used a current medication for >1year. Most (84%) had one or more parent-reported side effect. After adjusting for covariates, subjects with two medications reported 17% (p<0.001) and with three or more medications reported 38% (p=0.002) increases in their average number of side effects than did children taking one medication. Parental reporting of difficulties in accessing care also predicted a 42% (p<0.001) greater number of side effects than for those who had no access difficulties. Side effects were particularly more common in medication combinations including either selective serotonin reuptake inhibitors (SSRIs) (77% higher odds, p<0.001) or antipsychotics (99% higher odds, p<0.001). CONCLUSIONS: Side effects from psychiatric medications appear to be both more common and more severe overall with increasing numbers of medications utilized, and with perceived difficulty in accessing care. Polypharmacy regimens including either SSRIs or antipsychotics were especially associated with experiencing side effects, within this study sample.


Subject(s)
Polypharmacy , Psychotropic Drugs/adverse effects , Adolescent , Child , Child, Preschool , Female , Health Services Accessibility , Humans , Longitudinal Studies , Male
9.
Community Ment Health J ; 50(2): 172-8, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24323138

ABSTRACT

One thousand five hundred parents filling a psychiatric prescription for their 6-18 year old child with a multi-state retail pharmacy chain received a single mailed invitation to complete a detailed online survey. 276 parents responded (18.4%). 60% of children on medications had a parent rated CBCL scale score in the clinically significant range at enrollment (T score ≥65), with a similar frequency of clinically significant CBCL scores through 15 months of survey followup. 47% of medication regimens were noted to be causing persistent side effects. This simple community based data collection method can offer a unique way to investigate naturalistic treatment outcomes.


Subject(s)
Attitude to Health , Child Behavior Disorders/drug therapy , Health Surveys , Internet , Mental Disorders/drug therapy , Parents/psychology , Psychotropic Drugs/therapeutic use , Adolescent , Checklist , Child , Child Behavior Disorders/diagnosis , Child Behavior Disorders/psychology , Drug Therapy, Combination , Female , Follow-Up Studies , Humans , Male , Mental Disorders/diagnosis , Mental Disorders/psychology , Pharmaceutical Services , Psychotropic Drugs/adverse effects , Treatment Outcome
10.
AJR Am J Roentgenol ; 200(5): 1071-6, 2013 May.
Article in English | MEDLINE | ID: mdl-23617492

ABSTRACT

OBJECTIVE: The purpose of this study is to compare three CT image reconstruction algorithms for liver lesion detection and appearance, subjective lesion conspicuity, and measured noise. MATERIALS AND METHODS: Thirty-six patients with known liver lesions were scanned with a routine clinical three-phase CT protocol using a weight-based noise index of 30 or 36. Image data from each phase were reconstructed with filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR), and model-based iterative reconstruction (MBIR). Randomized images were presented to two independent blinded reviewers to detect and categorize the appearance of lesions and to score lesion conspicuity. Lesion size, lesion density (in Hounsfield units), adjacent liver density (in Hounsfield units), and image noise were measured. Two different unblinded truth readers established the number, appearance, and location of lesions. RESULTS: Fifty-one focal lesions were detected by truth readers. For blinded reviewers compared with truth readers, there was no difference for lesion detection among the reconstruction algorithms. Lesion appearance was statistically the same among the three reconstructions. Although one reviewer scored lesions as being more conspicuous with MBIR, the other scored them the same. There was significantly less background noise in air with MBIR (mean [± SD], 2.1 ± 1.4 HU) than with ASIR (8.9 ± 1.9 HU; p < 0.001) or FBP (10.6 ± 2.6 HU; p < 0.001). Mean lesion contrast-to-noise ratio was statistically significantly higher for MBIR (34.4 ± 29.1) than for ASIR (6.5 ± 4.9; p < 0.001) or FBP (6.3 ± 6.0; p < 0.001). CONCLUSION: In routine-dose clinical CT of the liver, MBIR resulted in comparable lesion detection, lesion characterization, and subjective lesion conspicuity, but significantly lower background noise and higher contrast-to-noise ratio compared with ASIR or FBP. This finding suggests that further investigation of the use of MBIR to enable dose reduction in liver CT is warranted.


Subject(s)
Algorithms , Artifacts , Liver Neoplasms/diagnostic imaging , Models, Biological , Radiographic Image Enhancement/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Computer Simulation , Data Interpretation, Statistical , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Signal-To-Noise Ratio
11.
Eur J Radiol ; 81(9): 2444-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-21703791

ABSTRACT

OBJECTIVE: To compare prospectively ECG gated CT pulmonary angiography (CTPA) with routine helical ungated CTPA for cardiac related motion artifacts and patient radiation dose. SUBJECTS AND METHODS: Twenty patients with signs and symptoms suspicious for pulmonary embolism and who had a heart rate below 85 were scanned with prospectively ECG gated CTPA. These gated exams were matched for several clinical parameters to exams from twenty similar clinical patients scanned with routine ungated helical CTPA. Three blinded independent reviewers subjectively evaluated all exams for overall pulmonary artery enhancement and for several cardiac motion related artifacts, including vessel blurring, intravascular shading, and double line. Reviewers also measured pulmonary artery intravascular density and image noise. Patient radiation dose for each technique was compared. Fourteen clinical prospectively ECG gated CTPA exams from a second institution were evaluated for the same parameters. RESULTS: Prospectively ECG gated CTPA resulted in significantly decreased motion-related image artifact scores in lung segments adjacent to the heart compared to ungated CTPA. Measured image noise was not significantly different between the two types of CTPA exams. Effective dose was 28% less for prospectively ECG gated CTPA (4.9 mSv versus 6.8 mSv, p=0.02). Similar results were found in the prospectively ECG gated exams from the second institution. CONCLUSION: Compared to routine helical ungated CTPA, prospectively ECG gated CTPA may result in less cardiac related motion artifact in lung segments adjacent to the heart and significantly less patient radiation dose.


Subject(s)
Artifacts , Cardiac-Gated Imaging Techniques/methods , Pulmonary Artery/diagnostic imaging , Pulmonary Embolism/diagnostic imaging , Radiation Dosage , Tomography, Spiral Computed/methods , Body Burden , British Columbia , Humans , Male , Middle Aged , Motion , Reproducibility of Results , Sensitivity and Specificity , United States
12.
Eur Radiol ; 22(1): 138-43, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21688003

ABSTRACT

OBJECTIVES: To compare routine dose liver CT reconstructed with filtered back projection (FBP) versus low dose images reconstructed with FBP and adaptive statistical iterative reconstruction (ASIR). METHODS: In this retrospective study, patients had a routine dose protocol reconstructed with FBP, and again within 17 months (median 6.1 months), had a low dose protocol reconstructed twice, with FBP and ASIR. These reconstructions were compared for noise, image quality, and radiation dose. RESULTS: Nineteen patients were included. (12 male, mean age 58). Noise was significantly lower in low dose images reconstructed with ASIR compared to routine dose images reconstructed with FBP (liver: p < .05, aorta: p < 0.001). Low dose FBP images were scored significantly lower for subjective image quality than low dose ASIR (2.1 ± 0.5, 3.2 ± 0.8, p < 0.001). There was no difference in subjective image quality scores between routine dose FBP images and low dose ASIR images (3.6 ± 0.5, 3.2 ± 0.8, NS).Radiation dose was 41% less for the low dose protocol (4.4 ± 2.4 mSv versus 7.5 ± 5.5 mSv, p < 0.05). CONCLUSIONS: Our initial results suggest low dose CT images reconstructed with ASIR may have lower measured noise, similar image quality, yet significantly less radiation dose compared with higher dose images reconstructed with FBP.


Subject(s)
Artifacts , Liver Cirrhosis/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted , Radiography, Abdominal/methods , Tomography, X-Ray Computed , Female , Humans , Liver Cirrhosis/pathology , Male , Middle Aged , Observer Variation , Radiation Dosage , Reproducibility of Results , Retrospective Studies , Tomography, X-Ray Computed/methods
13.
N Engl J Med ; 365(24): 2255-67, 2011 Dec 15.
Article in English | MEDLINE | ID: mdl-22085343

ABSTRACT

BACKGROUND: In patients with established cardiovascular disease, residual cardiovascular risk persists despite the achievement of target low-density lipoprotein (LDL) cholesterol levels with statin therapy. It is unclear whether extended-release niacin added to simvastatin to raise low levels of high-density lipoprotein (HDL) cholesterol is superior to simvastatin alone in reducing such residual risk. METHODS: We randomly assigned eligible patients to receive extended-release niacin, 1500 to 2000 mg per day, or matching placebo. All patients received simvastatin, 40 to 80 mg per day, plus ezetimibe, 10 mg per day, if needed, to maintain an LDL cholesterol level of 40 to 80 mg per deciliter (1.03 to 2.07 mmol per liter). The primary end point was the first event of the composite of death from coronary heart disease, nonfatal myocardial infarction, ischemic stroke, hospitalization for an acute coronary syndrome, or symptom-driven coronary or cerebral revascularization. RESULTS: A total of 3414 patients were randomly assigned to receive niacin (1718) or placebo (1696). The trial was stopped after a mean follow-up period of 3 years owing to a lack of efficacy. At 2 years, niacin therapy had significantly increased the median HDL cholesterol level from 35 mg per deciliter (0.91 mmol per liter) to 42 mg per deciliter (1.08 mmol per liter), lowered the triglyceride level from 164 mg per deciliter (1.85 mmol per liter) to 122 mg per deciliter (1.38 mmol per liter), and lowered the LDL cholesterol level from 74 mg per deciliter (1.91 mmol per liter) to 62 mg per deciliter (1.60 mmol per liter). The primary end point occurred in 282 patients in the niacin group (16.4%) and in 274 patients in the placebo group (16.2%) (hazard ratio, 1.02; 95% confidence interval, 0.87 to 1.21; P=0.79 by the log-rank test). CONCLUSIONS: Among patients with atherosclerotic cardiovascular disease and LDL cholesterol levels of less than 70 mg per deciliter (1.81 mmol per liter), there was no incremental clinical benefit from the addition of niacin to statin therapy during a 36-month follow-up period, despite significant improvements in HDL cholesterol and triglyceride levels. (Funded by the National Heart, Lung, and Blood Institute and Abbott Laboratories; AIM-HIGH ClinicalTrials.gov number, NCT00120289.).


Subject(s)
Atherosclerosis/drug therapy , Cholesterol, HDL/blood , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Hypolipidemic Agents/therapeutic use , Niacin/therapeutic use , Aged , Atherosclerosis/blood , Brain Ischemia/chemically induced , Brain Ischemia/epidemiology , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/mortality , Cholesterol, LDL/blood , Drug Therapy, Combination , Female , Humans , Hypolipidemic Agents/adverse effects , Kaplan-Meier Estimate , Male , Medication Adherence , Middle Aged , Muscular Diseases/chemically induced , Niacin/adverse effects , Proportional Hazards Models , Simvastatin/therapeutic use , Treatment Failure , Triglycerides/blood
14.
Resuscitation ; 82(8): 979-83, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21497983

ABSTRACT

INTRODUCTION: We examined the effect of the 2005 American Heart Association guidelines on survival in the Resuscitation Outcomes Consortium (ROC) Cardiac Arrest Epistry. METHODS: We surveyed 174 EMS agencies from 8 of 10 ROC sites to determine 2005 AHA guideline implementation, or crossover, date. Two sites with 2005 compatible treatment algorithms prior to guideline release, and agencies that did not adopt the new guidelines during the study period were excluded. Non-traumatic adult cardiac arrests that were not witnessed by EMS, and did not have do not resuscitate orders were included. A linear mixed effects model was applied for survival controlling for time and agency. The "crossover" date was added to the model to determine the effect of the 2005 guidelines. RESULTS: Of 174 agencies, 85 contributed cases to both cohorts during the 18 month period between 2005/12/01 and 2007/05/31. Of 7779 cases, 5054 occurred during the 13 month (median) interval before crossover and 2725 occurred in the five month (median) interval after crossover. The overall survival rate was 6.1%; 5.8% in the old cohort vs. 6.5%, p=0.23. For VF/VT patients, survival was 14.6% vs. 18.0%, p=0.063. Our model estimated no increase in survival over time (monthly OR 1.014, 95% CI 0.988, 1.041, p=0.28). CONCLUSION: This study found no significant change in survival rate over time in the early months after implementation. Further longitudinal study is needed to determine the full impact of the guidelines on survival and methods to translate knowledge quickly and effectively in EMS.


Subject(s)
Cardiopulmonary Resuscitation/standards , Emergency Medical Services/standards , Out-of-Hospital Cardiac Arrest/therapy , Practice Guidelines as Topic , Aged , Algorithms , American Heart Association , Analysis of Variance , Diffusion of Innovation , Female , Guideline Adherence , Humans , Linear Models , Male , Middle Aged , Out-of-Hospital Cardiac Arrest/mortality , Prospective Studies , Survival Rate , United States/epidemiology
15.
Prehosp Emerg Care ; 15(2): 184-92, 2011.
Article in English | MEDLINE | ID: mdl-21309705

ABSTRACT

BACKGROUND: Airway management remains a fundamental component of optimal care of the severely injured patient, with endotracheal intubation representing the definitive strategy for airway control. However, multiple studies document an association between out-of-hospital intubation and increased mortality for severe traumatic brain injury. OBJECTIVES: To explore the relationship between out-of-hospital intubation attempts and outcome among trauma patients with Glasgow Coma Scale (GCS) scores ≤ 8 across sites participating in the Resuscitation Outcomes Consortium (ROC). METHODS: The ROC Epistry-Trauma, an epidemiologic database of prehospital encounters with critically injured trauma victims, was used to identify emergency medical services (EMS)-treated patients with GCS scores ≤ 8. Multiple logistic regression was used to explore the association between intubation attempts and vital status at discharge, adjusting for the following covariates: age, gender, GCS score, hypotension, mechanism of injury, and ROC site. Sites were then stratified by frequency of intubation attempts and chi-square test for trend was used to associate the frequency of intubation attempts with outcome. RESULTS: A total of 1,555 patients were included in this analysis; intubation was attempted in 758 of these. Patients in whom intubation was attempted had higher mortality (adjusted odds ratio [OR] 2.91, 95% confidence interval [CI] 2.13-3.98, p < 0.01). However, sites with higher rates of attempted intubation had lower mortality across all trauma victims with GCS scores ≤ 8 (OR 1.40, 95% CI 1.15-1.72, p < 0.01). CONCLUSIONS: Patients in whom intubation is attempted have higher adjusted mortality. However, sites with a higher rate of attempted intubation have lower adjusted mortality across the entire cohort of trauma patients with GCS scores ≤ 8. Coma Scale score.


Subject(s)
Airway Management/methods , Brain Injuries/therapy , Emergency Medical Services/methods , Adult , Brain Injuries/mortality , Female , Glasgow Coma Scale , Humans , Injury Severity Score , Logistic Models , Male , Prognosis , Registries , Risk Assessment , Treatment Outcome , United States
16.
Resuscitation ; 82(3): 277-84, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21159416

ABSTRACT

OBJECTIVES: To identify variation in patient, event, and scene characteristics of out-of-hospital cardiac arrest (OOHCA) patients assessed by emergency medical services (EMS), and to investigate variation in transport practices in relation to documented prehospital return of spontaneous circulation (ROSC) within eight regional clinical centers participating in the Resuscitation Outcomes Consortium (ROC) Epistry-Cardiac Arrest. METHODS: OOHCA patient, event, and scene characteristics were compared to identify variation in treatment and transport practices across sites. Findings were adjusted for site and standard Utstein covariates. Using logistic regression, these covariates were modeled to identify factors related to the initiation of transport without documented prehospital ROSC as well as survival in these patients. SETTING: Eight US and Canadian sites participating in the ROC Epistry-Cardiac Arrest. POPULATION: Persons ≥ 20 years with OOHCA who (a) received compressions or shock by EMS providers and/or received bystander AED shock or (b) were pulseless but received no EMS compressions or shock between December 2005 and May 2007. RESULTS: 23,233 OOHCA cases were assessed by EMS in the defined period. Resuscitation (treatment) was initiated by EMS in 13,518 cases (58%, site range: 36-69%, p < 0.0001). Of treated cases, 59% were transported (site range: 49-88%, p < 0.0001). Transport was initiated in the absence of documented ROSC for 58% of transported cases (site range: 14-95%, p < 0.0001). Of these transported cases, 8% achieved ROSC before hospital arrival (site range: 5-21%, p < 0.0001) and 4% survived to hospital discharge (site range: 1-21%, p < 0.0001). In cases with transport from the scene initiated after documented ROSC, 28% survived to hospital discharge (site range: 18-44%, p < 0.0001). CONCLUSION: Initiation of resuscitation and transport of OOHCA and the reporting of ROSC prior to transport markedly varies among ROC sites. This variation may help clarify reported differences in survival rates among sites and provide a target for identifying EMS practices most likely to enhance survival from OOHCA.


Subject(s)
Out-of-Hospital Cardiac Arrest/therapy , Resuscitation/methods , Transportation of Patients/methods , Aged , Community Networks , Female , Humans , Logistic Models , Male , Middle Aged , North America , Out-of-Hospital Cardiac Arrest/mortality , Prospective Studies , Registries
17.
Prehosp Emerg Care ; 14(3): 355-60, 2010.
Article in English | MEDLINE | ID: mdl-20388032

ABSTRACT

INTRODUCTION: In 2005, the American Heart Association (AHA) released guidelines to improve survival rates from out-of-hospital cardiac arrest (OHCA). OBJECTIVE: To determine if, and when, emergency medical services (EMS) agencies participating in the Resuscitation Outcomes Consortium (ROC) implemented these guidelines. METHODS: We contacted 178 EMS agencies and completed structured telephone interviews with 176 agencies. The survey collected data on specific treatment protocols before and after implementation of the 2005 guidelines as well as the date of implementation crossover (the "crossover date"). The crossover date was then linked to a database describing the size, type, and structure of each agency. Descriptive statistics and regression were used to examine patterns in time to crossover. RESULTS: The 2005 guidelines were implemented by 174 agencies (99%). The number of days from guideline release to implementation was as follows: mean 416 (standard deviation 172), median 415 (range 49-750). There was no difference in time to implementation in fire-based agencies (mean 432), nonfire municipal agencies (mean 365), and private agencies (mean 389, p = 0.31). Agencies not providing transport took longer to implement than agencies that transported patients (463 vs. 384 days, p = 0.004). Agencies providing only basic life support (BLS) care took longer to implement than agencies who provided advanced life support (ALS) care (mean 462 vs. 397 days, p = 0.03). Larger agencies (>10 vehicles) were able to implement the guidelines more quickly than smaller agencies (mean 386 vs. 442 days, p = 0.03). On average, it took 8.9 fewer days to implement the guidelines for every 50% increase in EMS-treated runs/year to which an agency responded. CONCLUSION: ROC EMS agencies required an average of 416 days to implement the 2005 AHA guidelines for OHCA. Small EMS agencies, BLS-only agencies, and nontransport agencies took longer than large agencies, agencies providing ALS care, and transport agencies, respectively, to implement the guidelines. Causes of delays to guideline implementation and effective methods for rapid EMS knowledge translation deserve investigation.


Subject(s)
American Heart Association , Cardiopulmonary Resuscitation/methods , Emergency Medical Services , Guideline Adherence , Guidelines as Topic , Canada , Health Care Surveys , Heart Arrest/therapy , Humans , United States
18.
Acad Emerg Med ; 16(12): 1269-1276, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20053248

ABSTRACT

OBJECTIVES: The objective was to compare the type, rate, and selection of injured patients for out-of-hospital airway procedures among emergency medical services (EMS) agencies in 10 sites across North America. METHODS: The authors analyzed a consecutive patient, prospective cohort registry of injured adults and children with an out-of-hospital advanced airway attempt, collected from December 1, 2005, through February 28, 2007, by 181 EMS agencies in 10 sites across the United States and Canada. Advanced airway procedures were defined as orotracheal intubation, nasotracheal intubation, supraglottic airway, or cricothyrotomy. Airway procedure rates were calculated based on age-specific population values for the 10 sites and the number of injured patients with field physiologic abnormality (systolic blood pressure of < or = 90 mm Hg, respiratory rate of <10 or >29 breaths/min, Glasgow Coma Scale [GCS] score of < or = 12). Descriptive measures were used to compare patients between sites. RESULTS: A total 1,738 patients had at least one advanced airway attempt and were included in the analysis. There was wide variation between sites in the types of airway procedures performed, including orotracheal intubation (63% to 99%), supraglottic airways (0 to 27%), nasotracheal intubation (0 to 21%), and cricothyrotomy (0 to 2%). Use of rapid sequence intubation (RSI) varied from 0% to 65%. The population-adjusted rates of field airway intervention (by site) ranged from 1.2 to 22.8 per 100,000 adults and 0.2 to 4.0 per 100,000 children. Among trauma patients with physiologic abnormality, some sites performed airway procedures in almost 50% of patients, while other sites used these procedures in fewer than 10%. There was also large variation in demographic characteristics, physiologic measures, mechanism of injury, mode of transport, field cardiopulmonary resuscitation, and unadjusted mortality among airway patients. CONCLUSIONS: Among 10 sites across North America, there was wide variation in the types of out-of-hospital airway procedures performed, population-based rates of airway intervention, and the selection of injured patients for such procedures.


Subject(s)
Cardiopulmonary Resuscitation/statistics & numerical data , Emergency Medical Services/statistics & numerical data , Intubation, Intratracheal/statistics & numerical data , Wounds and Injuries/therapy , Adult , Age Distribution , Canada/epidemiology , Cardiopulmonary Resuscitation/methods , Child , Cohort Studies , Emergency Medical Services/methods , Humans , Intubation, Intratracheal/methods , Patient Selection , United States/epidemiology , Wounds and Injuries/epidemiology
19.
J Lipid Res ; 44(11): 2161-8, 2003 Nov.
Article in English | MEDLINE | ID: mdl-12923221

ABSTRACT

Small, dense LDLs and hypertriglyceridemia, two highly correlated and genetically influenced risk factors, are known to predict for risk of coronary heart disease. The objective of this study was to perform a whole-genome scan for linkage to LDL size and triglyceride (TG) levels in 26 kindreds with familial hypertriglyceridemia (FHTG). LDL size was estimated using gradient gel electrophoresis, and genotyping was performed for 355 autosomal markers with an average heterozygosity of 76% and an average spacing of 10.2 centimorgans (cMs). Using variance components linkage analysis, one possible linkage was found for LDL size [logarithm of odds (LOD) = 2.1] on chromosome 6, peak at 140 cM distal to marker F13A1 (closest marker D6S2436). With adjustment for TG and/or HDL cholesterol, the LOD scores were reduced, but remained in exactly the same location. For TG, LOD scores of 2.56 and 2.44 were observed at two locations on chromosome 15, with peaks at 29 and 61 cM distal to marker D15S822 (closest markers D15S643 and D15S211, respectively). These peaks were retained with adjustment for LDL size and/or HDL cholesterol. These findings, if confirmed, suggest that LDL particle size and plasma TG levels could be caused by two different genetic loci in FHTG.


Subject(s)
Cholesterol, LDL/chemistry , Genome, Human , Hyperlipoproteinemia Type IV/genetics , Quantitative Trait Loci/genetics , Triglycerides/blood , Apolipoproteins/chemistry , Cholesterol, HDL/chemistry , Chromosome Mapping , Chromosomes, Human, Pair 15/genetics , Genomics , Humans , Hyperlipoproteinemia Type IV/blood , Lod Score
20.
Am J Pathol ; 162(2): 665-72, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12547724

ABSTRACT

Patients with extensive ulcerative colitis (UC) of longer than 8 years duration are at high risk for the development of colorectal cancer. The cancers in these patients appear to develop in a stepwise manner with progressive histological changes from negative for dysplasia --> indefinite for dysplasia --> dysplasia --> cancer. The aim of this study was to determine the timing and extent of genomic instability in the progression of UC dysplasia and cancer. Using two polymerase chain reaction (PCR)-based DNA fingerprinting methods, arbitrarily primed PCR and intersimple sequence repeat PCR, we assessed DNA sequence variation in biopsies across the spectrum of cancerous, dysplastic, and nondysplastic mucosa. UC patients with dysplasia/cancer had substantial genomic instability in both their dysplastic and nondysplastic colonic mucosa, whereas instability was not present in the majority of UC patients without dysplasia/cancer. The degree of instability in nondysplastic tissue was similar to that of dysplastic/cancerous mucosa from the same patient, suggesting that this instability was widespread and reached the maximum level early in neoplastic progression. These results suggest that UC patients who develop dysplasia or cancer have an underlying process of genomic instability in their colonic mucosa whereas UC patients who are dysplasia-free do not.


Subject(s)
Colitis, Ulcerative/genetics , Colitis, Ulcerative/pathology , Colonic Neoplasms/genetics , Colonic Neoplasms/pathology , DNA Fingerprinting/methods , DNA/genetics , Biopsy , Colitis, Ulcerative/diagnosis , Colonic Neoplasms/diagnosis , Colonic Neoplasms/etiology , DNA Primers , Diagnosis, Differential , Disease Progression , Humans , Intestinal Mucosa/pathology , Polymerase Chain Reaction/methods , Reproducibility of Results , Sensitivity and Specificity
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