Publications by authors named "Hyo-Chun Yoon"

28 Publications

  • Page 1 of 1

Rapidly Destructive Hip Disease Following Intra-Articular Corticosteroid Injection of the Hip.

J Bone Joint Surg Am 2021 Sep 22. Epub 2021 Sep 22.

Department of Diagnostic Imaging, Hawaii Permanente Medical Group, Honolulu, Hawaii.

Background: While recent reports have suggested that hip corticosteroid injections can hasten joint degeneration, there are few published data on the topic. The purpose of the present study was to evaluate for an association between corticosteroid injection and rapidly destructive hip disease (RDHD) and to determine the rate of, and risk factors for, occurrence.

Methods: This study was conducted in 2 parts. First, to assess for a potential association between hip corticosteroid injection and RDHD, a case-control analysis was performed. Patients who developed RDHD between 2013 and 2016 served as cases, whereas those who underwent total hip arthroplasty for diagnoses other than RDHD during the same period served as controls, and the exposure of interest was prior intra-articular hip corticosteroid injection. Second, in a retrospective cohort analysis, we analyzed all patients who received a fluoroscopically guided intra-articular hip corticosteroid injection at our institution from 2013 to 2016. The rate of post-injection RDHD was determined, and logistic regression was used to identify risk factors for occurrence.

Results: In the case-control analysis, hip corticosteroid injection was associated with the development of RDHD (adjusted odds ratio, 8.56 [95% confidence interval, 3.29 to 22.3], p < 0.0001). There was evidence of a dose-response curve, with the risk of RDHD increasing with injection dosage as well as with the number of injections received. In the retrospective cohort analysis, the rate of post-injection RDHD was 5.4% (37 of 688). Cases of post-injection RDHD were diagnosed at an average of 5.1 months following injection and were characterized by rapidly progressive joint-space narrowing, osteolysis, and collapse of the femoral head.

Conclusions: This study documents an association between hip corticosteroid injection and RDHD. While the risk of RDHD following a single low-dose (≤40 mg) triamcinolone injection is low, the risk is higher following high-dose (≥80 mg) injection and multiple injections. These findings provide information that can be used to counsel patients about the risks associated with this common procedure. In addition, caution should be taken with intra-articular hip injections utilizing ≥80 mg of corticosteroid and multiple injections.

Level Of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2106/JBJS.20.02155DOI Listing
September 2021

Recommended D-Dimer Use in Suspected Pulmonary Embolism Is Insufficient to Curb the Long-Term Overutilization of CT Pulmonary Angiography.

J Am Coll Radiol 2021 Jul 14. Epub 2021 Jul 14.

Department of Radiology, Hawaii Permanente Medical Group, Honolulu, Hawaii.

Purpose: The aim of this study was to determine whether the authors' emergency medicine department has seen a significant change in CT pulmonary angiography (CTPA) utilization or positive rates for pulmonary embolism (PE) over a 10-year period for the 2 years before and 8 years after the implementation of patient population-specific D-dimer recommendations.

Methods: A retrospective chart review was performed among all patients belonging to a geographically isolated health maintenance organization who underwent CTPA for the evaluation of acute PE in the emergency department between 2010 and 2019. The positive rate for acute PE among these studies was calculated and stratified by serum D-dimer value collected within 48 hours previously.

Results: A total of 6,013 CT pulmonary angiographic studies were reviewed, of which 40.2% had serum D-dimer ≥ 1.0 μg/mL (positive rate 10.6%), 42.5% did not have serum D-dimer drawn (positive rate 7.3%), and 17.2% had serum D-dimer < 1.0 μg/mL (positive rate 0.6%). There was a significant increase in positivity on CTPA in 2012 with the health group's formal recommendation of a D-dimer cutoff of 1.0 μg/mL. This improvement also corresponded with fewer orders for CTPA after a negative D-dimer result. However, in the following years, CTPA utilization and percentage positivity were found to be reverting to the prerecommendation statistics.

Conclusions: The failure to mandate the use of serum D-dimer with a higher threshold value for patients who are to undergo CTPA for possible PE has resulted in poor lasting compliance despite promising early results. A firmer approach is likely necessary to yield positive long-term outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jacr.2021.06.021DOI Listing
July 2021

Effects of Implementing a Higher Threshold for Recommending Thyroid Biopsies on Malignancy Rates.

Perm J 2021 05;25

Hawaii Permanente Medical Group, Honolulu, HI.

Introduction: We implemented a new thyroid nodule classification system in which a biopsy was recommended for thyroid lesions ≥ 1 cm with at least 2 or more suspicious features.

Methods: Three consecutive years of thyroid biopsies using the new classification system were reviewed for patient demographics, biopsy recommendation based on nodule size and imaging characteristics, and pathology results. The primary outcome was malignancy rates for thyroid biopsies. These results were compared to a 3-year historical data set.

Results: Review of thyroid biopsies from 2010 to 2012, prior to the implementation of current recommendations, revealed 996 thyroid biopsies with a malignancy rate of 12.8%. Subsequent to the new classification system in 2017, 483 thyroid biopsies were performed over the next 3 years with a malignancy rate of 21.9%.

Discussion: Implementation of the new classification system with a higher threshold for biopsy reduced our yearly biopsy volume by approximately 50% while also increasing our malignancy rate from 12.8% to 21.9%, which is more in line with published rates of malignancy.

Conclusion: In a community setting performing less than 200 biopsies per year, the use of more stringent requirements for thyroid biopsy are necessary to achieve malignancy rates comparable to the published literature.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7812/TPP/20.240DOI Listing
May 2021

The Utility of Brain Magnetic Resonance Imaging/Angiography and Neck Magnetic Resonance Angiography in Patients with Suspected Acute Stroke.

Perm J 2021 05;25

Department of Diagnostic Imaging, Kaiser Permanente Moanalua Medical Center, Honolulu, HI.

Background: In our health maintenance organization, we have seen a trend among our referring physicians to order simultaneous brain magnetic resonance imaging (MRI), head magnetic resonance angiography (MRA), and neck MRA in the evaluation of patients for acute stroke. However, there are little data to demonstrate any improvement in patient care resulting from ordering this triple study. The objective of this study was to analyze the utility of the triple MRI/MRA study for patients who experience stroke-like symptoms.

Methods: We reviewed all triple-study cases between January 1, 2013 and December 31, 2016. We recorded whether or not an acute stroke occurred, the presence or absence of a major stenosis in the intracranial and/or neck arteries, subsequent percutaneous endovascular or open surgical intervention within 90 days, and any follow-up computed tomography angiography or carotid ultrasound studies within 30 days.

Results: During the studied period, 591 triple studies were ordered, and 162 patients (27.4%) were found to have moderate or severe stenosis. Of the patients who had an acute stroke, 100 (48.3%) also had a major stenosis. Of 591 patients, only 15 (2.5%) underwent percutaneous endovascular or open surgical intervention within 90 days. Of these, 4 patients had an intervention in less than a week; in all of the cases, the triple study did not need to be ordered simultaneously to achieve the same clinical outcome.

Conclusion: Brain MRI, head MRA, and neck MRA studies should not be ordered simultaneously as a generalized response to patients presenting with acute stroke-like symptoms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7812/TPP/20.214DOI Listing
May 2021

One-View Chest Radiograph for Initial Management of Most Ambulatory Patients with Rib Pain.

J Am Board Fam Med 2021 Jan-Feb;34(1):144-150

From Pomona College, Claremont, CA (EN); School of Medicine, Creighton University, Omaha, NE (AF); Brain and Spinal Injury Center, University of California, San Francisco, CA (MH); Hawaii Permanente Medical Group, Honolulu, HI (HCY).

Introduction: Rib series are frequently ordered for ambulatory patients who complain of rib pain or have suffered chest trauma. However, the utility of rib series has been questioned in previous studies. The objective of this study was to compare the efficacy of rib series to a single view posteroanterior chest radiograph in the clinical management of most ambulatory patients with rib pain.

Methods: We reviewed all rib series for rib pain performed between January 1, 2016 and December 31, 2016, excluding patients with suspected bony metastasis, chest or rib deformities, and follow-up studies for prior rib series. We recorded any follow-up imaging and/or surgical intervention within 30 ± 7 days, fracture diagnosis, and complications relating to rib fractures.

Results: One thousand seven hundred ninety-one rib series were performed during the study period. Of these, 1168 (65.2%) rib series were performed because of trauma as reported in the clinical indication (trauma cohort). Six hundred twenty-three (34.8%) of the rib series were performed for clinical indications which did not specify acute trauma (nontrauma cohort). There were 323 (17.9%) rib series that resulted in a fracture diagnosis and 95 (5.3%) that resulted in a possible fracture diagnosis. There were 50 (2.8%) effusions, 7 (0.4%), pneumothoraces, and 1 (0.1%) hemothorax detected. Two patients, 1 each from the trauma and nontrauma cohorts, underwent subsequent intervention during the follow-up period. In both cases, the findings which led to the subsequent intervention could be seen on the initial posteroanterior chest radiograph.

Conclusion: Single-view chest radiograph provides sufficient information for the clinical management of ambulatory patients with rib pain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3122/jabfm.2021.01.200276DOI Listing
August 2021

Inadequate Clinical Indications in Computed Tomography Chest and Abdomen/Pelvis Scans.

Perm J 2018 ;22:18-017

Assistant Chief of Diagnostic Imaging for the Hawaii Permanente Medical Group

Context: As the use of computed tomography (CT) scans, which are expensive and result in considerable radiation exposure to the patient, continues to increase, communication between physicians and radiologists remains vital to explain the clinical context for the examination. However, the clinical information provided to the radiologist is often lacking.

Objective: To determine whether the clinical information provided in CT scan requests meets minimum criteria for requesting the examination.

Methods: We reviewed the clinical indications for 400 CT chest scans and 400 CT abdomen/pelvis scans performed from January 1, 2016, through March 8, 2016. We determined whether each CT study indication was complete on the basis of whether the clinical information included an adequate clinical history with 1) a primary symptom, 2) the location of the symptom, and 3) the duration of the symptom as well as a suspected etiology.

Results: Of the CT chest indications, 56 (14.0%) of the clinical histories were considered complete and 17 (4.3%) had none of the components. A principal etiology was included in 195 (48.8%) of the indications. Of the CT abdomen/pelvis indications, 94 (23.5%) of the clinical histories were complete and 13 (3.3%) had none of the components. A principal etiology was included in 173 (43.3%) of the indications. Only 23 (5.8%) of the CT chest studies and 35 (8.8%) of the CT abdomen/pelvis studies had information considered sufficient for the radiologist.

Conclusion: The percentage of complete clinical indications for both CT chest and abdomen/pelvis scans was much lower than 50%, suggesting that more emphasis should be placed on providing complete clinical indications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7812/TPP/18-017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6175600PMC
May 2019

Appropriate Interval for Imaging Follow-up of Small Simple Pancreatic Cysts.

Perm J 2017 ;21:17-040

Radiologist in the Department of Diagnostic Imaging at the Moanalua Medical Center in Honolulu, HI.

Context: The frequency at which patients should undergo follow-up imaging of small pancreatic cysts is problematic because different medical societies have different follow-up guidelines.

Objective: To determine whether short-term follow-up of small pancreatic cysts is necessary to detect pancreatic cancer or cystic neoplasia.

Design: We retrospectively reviewed all abdominal magnetic resonance imaging (MRI) studies obtained in a geographically isolated health maintenance organization between January 1, 2012, and December 31, 2014, looking for pancreatic cysts. For each patient with one or more simple cysts, we recorded the size of the largest cyst. For patients with cysts, all their other computed tomography and MRI studies were reviewed to determine any change in size or morphology. The electronic medical record of every patient who underwent MRI was reviewed to determine development of pancreatic cancer.

Main Outcome Measures: Change in cyst size on images.

Results: Of 1946 patients, 342 were found to have at least 1 pancreatic cyst. A total of 228 patients had additional imaging from which to determine rates of change. The mean rate (standard deviation) of change for these cysts was 0.1 ± 2.0 mm/y. None of those cysts measuring 2 cm or smaller on MRI grew more than 5 mm in 2 years.

Conclusion: Our data validate the clinical efficacy of obtaining follow-up imaging no sooner than 24 months after the initial detection of a simple pancreatic cyst 2 cm or smaller. Patients with cysts are more likely to have pancreatic cancer, but earlier follow-up imaging would not change their diagnosis of pancreatic cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7812/TPP/17-040DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5593508PMC
June 2018

Risk of Venous Thromboembolism after a Single Normal Proximal Lower Extremity Venous Ultrasound.

Perm J 2017 ;21:16-140

Assistant Chief of Diagnostic Imaging for the Hawaii Permanente Medical Group.

Context: The optimal lower extremity venous ultrasound (US) protocol to diagnose deep venous thrombosis of the popliteal and more proximal veins is unclear.

Objective: To determine the three-month rate of symptomatic venous thromboembolism (VTE) and clinical outcomes of inpatients and ambulatory patients with normal findings on single venous ultrasound of the popliteal and more proximal veins (single proximal US).

Design: Single proximal US results and clinical data of all inpatient and ambulatory patients with suspected acute deep venous thrombosis were retrospectively reviewed during a 12-month period between January and December 2014. Three-month follow-up data were reviewed for all these patients, who received all their care from a single geographically isolated health maintenance organization.

Main Outcome Measures: Three-month rate of symptomatic VTE and clinical outcomes after an initially normal single proximal US result.

Results: Of 1295 patients, 111 (8.6%) were found to have acute deep venous thrombosis on the initial proximal US. Of the remaining 1184 patients with initially normal results on proximal US who were sampled at 3-month follow-up, 1075 patients (90.8%) had no venous thromboembolic event. Among the others, 11 (0.9%) had a subsequent imaging-confirmed venous thromboembolic event, 53 (4.5%) died (none owing to venous thromboembolism), and 45 (3.8%) did not complete follow-up.

Conclusion: Symptomatic VTE after an initially normal single proximal US result occurred in less than 1% of this cohort. Therefore, serial proximal US is unnecessary for most of our patients, and its elimination will save time and out-of-pocket expenses.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7812/TPP/16-140DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391780PMC
September 2017

Evaluation of Small Adrenal Incidental Nodules: Is Imaging Follow-Up Necessary?

Perm J 2016 21;20(1):13-18. Epub 2015 Dec 21.

Associate Chief of Diagnostic Imaging at the Moanalua Medical Center in HI.

Introduction: Low incidence of adrenal cortical carcinoma in the general adult population has prompted a reevaluation of current protocol for the assessment of adrenal incidentalomas.

Objective: To determine whether follow-up imaging for small (≤ 4 cm) incidental adrenal nodules is necessary for patients without known cancer.

Methods: We performed a retrospective analysis of all patients found to have an incidental adrenal nodule on abdominal computed tomography (CT) scan during a 27-month period. The electronic medical record was reviewed to determine clinical outcomes in all patients with a minimum of 3 years of follow-up (mean follow-up = 6.7 years). Patients with a known primary cancer were excluded from the analysis unless they had a prior CT scan that documented an incidental adrenal nodule. Unenhanced CT attenuation was measured for all nodules, if available.

Results: A total of 392 patients with an incidental adrenal nodule had a mean (standard deviation [SD]) clinical follow-up of 6.7 (2.7) years. There were 200 men and 192 women with a mean (SD) age of 66.0 (13.2) years. None of these patients developed primary adrenocortical carcinoma during the follow-up period.Two hundred forty of these patients also had a minimum 3 years of imaging follow-up (mean [SD], 6.4 [2.4] years; range, 3.1-13.6 years). There were 173 left-sided and 91 right-sided nodules on index CT scan. There was no significant difference in the mean (SD) rate of growth between left- and right-sided nodules (0.1 [0.8] mm/year vs 0.1 [0.8] mm/year, p = 0.58). Mean unenhanced CT attenuation of adrenal nodules did not affect the likelihood of adrenal malignancy during follow-up.

Conclusion: Patients with small incidental adrenal nodules do not require additional imaging to exclude the possibility of adrenocortical carcinoma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7812/TPP/15-037DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4732789PMC
December 2016

Improving appropriate use of pulmonary computed tomography angiography by increasing the serum D-dimer threshold and assessing clinical probability.

Perm J 2014 ;18(4):10-5

Assistant Chief of Diagnostic Imaging at the Moanalua Medical Center in Honolulu, HI.

Objective: To determine whether the implementation of an increased D-dimer threshold value and clinical probability assessment increases the prevalence of pulmonary embolism (PE) in patients undergoing pulmonary computed tomography angiography (PCTA) in an Emergency Department setting.

Methods: A retrospective review of all patients undergoing PCTA during 2 separate 12-month intervals, 1 before the implementation of an increased D-dimer threshold and recommendation for formal clinical probability assessment and the other after regional implementation. The primary outcome measure was the prevalence of acute PE in each of the samples.

Results: After the implementation of the increased D-dimer threshold and recommendation for formal clinical probability assessment, the prevalence of PE detected by PCTA increased from 4.7% to 11.7% (p < 0.001). Among all PCTAs performed after the new guidelines were promulgated, 8.6% were still performed on patients who had serum D-dimer values lower than the threshold of 1.0 µg/mL. Despite the recommendation for formal clinical probability assessment before ordering a PCTA, only 4% of patients had a formal clinical probability assessment recorded in their electronic medical record.

Conclusion: The implementation of an increased D-dimer threshold value increased the prevalence of PE in patients undergoing PCTA in an Emergency Department setting, but more consistent application of clinical probability assessment remains an elusive target.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7812/TPP/14-007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4206165PMC
October 2015

Journal Club: Head CT scans in the emergency department for syncope and dizziness.

AJR Am J Roentgenol 2015 Jan;204(1):24-8

1 John A. Burns School of Medicine, University of Hawaii, Honolulu, HI.

Objective: The purpose of this study was to determine the yield of acutely abnormal findings on head CT scans in patients presenting to the emergency department with dizziness, near-syncope, or syncope and to determine the clinical factors that potentially predicted acutely abnormal head CT findings and hospital admission.

Materials And Methods: We retrospectively reviewed the electronic medical records of all patients presenting to an HMO emergency department between July 1, 2012, and December 31, 2012, who underwent head CT for a primary complaint of dizziness, syncope, or near-syncope. The primary outcomes were head CT scans with acutely abnormal findings and hospital admission. Binary logistic regression was used to assess the association between clinical variables and acute head CT findings and between clinical variables and hospital admission.

Results: Of the 253 patients who presented with dizziness, 7.1% had head CT scans with acutely abnormal findings, and 18.6% were admitted. Of the 236 patients who presented with syncope or near-syncope, 6.4% had head CT scans with acutely abnormal findings, and 39.8% were admitted. The following three clinical factors were found to be significantly correlated with acutely abnormal head CT findings: a focal neurologic deficit (p = 0.003), age greater than 60 years (p = 0.011), and acute head trauma (p = 0.026).

Conclusion: Our results suggest that most patients presenting with syncope or dizziness to the emergency department may not benefit from head CT unless they are older, have a focal neurologic deficit, or have a history of recent head trauma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2214/AJR.14.12993DOI Listing
January 2015

Carotid MRI Detection of Intraplaque Hemorrhage at 3T and 1.5T.

J Neuroimaging 2015 May-Jun;25(3):390-6. Epub 2014 Jul 15.

Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah School of Medicine, Salt Lake City, UT.

Background And Purpose: Carotid intraplaque hemorrhage leads to plaque progression and ischemic events. Detection can be accomplished with 3T T1w sequences, but may be limited by false-positive lipid/necrosis. The purpose of this study was threefold: (1) to determine if magnetization-prepared rapid acquisition with gradient-echo (MPRAGE) detects intraplaque hemorrhage versus lipid/necrosis; (2) if 3T MPRAGE image quality is retained at 1.5T; and (3) to determine observer agreement.

Methods: MPRAGE positive areas were compared to hemorrhage and lipid/necrosis areas from 100 carotid endarterectomy slides in 12 subjects using multivariable linear regression. Image quality was determined between 3T and 1.5T in 716 carotid arteries using t-tests and multivariable linear regression. Kappa analysis was used to determine agreement.

Results: Intraplaque hemorrhage, not lipid/necrosis, was a significant predictor of MPRAGE positive area before and after adjusting for confounders (slope = .52 vs. .51, P < .001). Image quality at 3T was slightly lower than 1.5T (mean 3.87 vs. 4.34, P < .0001). 3T image quality remained slightly decreased before and after adjusting for confounders (slope = -.46 vs. -.41, P < .001). Kappa values for inter-/intraobserver agreement were .807/.919 at 3T and .803/.871 at 1.5T.

Conclusions: Carotid MPRAGE detects intraplaque hemorrhage, not lipid/necrosis. 3T image quality was retained at 1.5T with very good observer agreement.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jon.12146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5441880PMC
February 2016

Four-year cumulative radiation exposure in patients undergoing computed tomography angiography for suspected pulmonary embolism.

Radiol Res Pract 2013 28;2013:482403. Epub 2013 Jul 28.

John A. Burns School of Medicine at the University of Hawaii, 651 Ilalo Street Honolulu, HI 96813, USA.

Purpose. The objective of this study was to determine the estimated effective radiation dose of pulmonary CT angiography (CTA) for suspected pulmonary embolism (PE) contributing to total medical radiation exposure over a 4-year period. Materials and Methods. This investigation retrospectively reviewed 300 patients who presented to the emergency department and received a pulmonary CTA scan for suspected PE. We evaluated these patients' electronic medical record to determine their estimated radiation exposure to CT scans during the following four years. Using DLP to E conversion coefficients, we calculated the cumulative effective radiation dose each subject received. Results. A total of 900 CT scans were reviewed in this study. Pulmonary CTA delivered an average effective radiation dose of 10.7 ± 2.5 mSv and accounted for approximately 65% of subjects' 4-year cumulative medical radiation dose. Only 6.3% of subjects had a positive acute PE according to their radiology report. Conclusion. Pulmonary CTA accounted for the majority of subjects' medically related effective radiation dose over a 4-year period. With only a minority of subjects having positive findings for acute PE, increased efforts should be made to clinically assess pretest probability before the consideration of imaging.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2013/482403DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3745975PMC
August 2013

Carotid magnetization-prepared rapid acquisition with gradient-echo signal is associated with acute territorial cerebral ischemic events detected by diffusion-weighted MRI.

Circ Cardiovasc Imaging 2012 May 11;5(3):376-82. Epub 2012 Apr 11.

Department of Radiology, Utah Center for Advanced Imaging Research, University of Utah School of Medicine, Salt Lake City, UT 84132-2140, USA.

Background: Carotid intraplaque hemorrhage has been associated with symptomatic stroke and can be accurately detected with magnetization-prepared rapid acquisition with gradient-echo (MPRAGE). Currently, there are no studies analyzing carotid MPRAGE signal and territorial ischemic events defined by diffusion restriction in the acute setting. Our aim was to determine the association of carotid MPRAGE signal with acute territorial ischemic events using carotid MPRAGE and brain diffusion tensor imaging.

Methods And Results: After the addition of the MPRAGE sequence to the neck MR angiographic protocol, 159 patients with suspected acute stroke were evaluated with both brain diffusion tensor imaging and carotid MPRAGE sequences over 2 years, providing 318 carotid artery and paired brain images for analysis. Forty-eight arteries were excluded due to extracarotid sources of brain ischemia and 4 were excluded due to carotid occlusion. Two hundred sixty-six arteries were eligible for data analysis. Carotid MPRAGE-positive signal was associated with an acute cerebral territorial ischemic event with a relative risk of 6.4 (P<0.001). The relative risk of a diffusion tensor imaging-positive territorial ischemic event with carotid MPRAGE-positive signal was increased in mild, moderate, and severe stenosis categories (10.3, P<0.001; 2.9, P=0.01; and 2.2, P=0.01, respectively).

Conclusions: In the workup of acute stroke, carotid MPRAGE-positive signal was associated with an increased risk of territorial cerebral ischemic events as detected objectively by brain diffusion tensor imaging. The relative risk of stroke was increased in all carotid stenosis categories but was most elevated in the mild stenosis category.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1161/CIRCIMAGING.111.967398DOI Listing
May 2012

Affiliation and control during marital disagreement, history of divorce, and asymptomatic coronary artery calcification in older couples.

Psychosom Med 2011 May 1;73(4):350-7. Epub 2011 Mar 1.

Department of Psychology, University of Utah, 380 South 1530 East, Room 502, Salt Lake City, UT 84112, USA.

Objective: To examine behavioral observations of affiliation (ie, warmth versus hostility) and control (ie, dominance versus submissiveness) and prior divorce as predictors of coronary artery calcification (CAC) in older couples. In some but not all studies, marital disruption and low marital quality have been shown to confer risk of coronary artery disease (CAD). Inconsistencies might reflect limitations of self-reports of marital quality compared with behavioral observations. Also, aspects of marital quality related to CAD might differ for men and women.

Methods: Couples underwent computed tomography scans for CAC and marital assessments, including observations of laboratory-based disagreement. Participants were 154 couples (mean age, 63.5 years; mean length of marriage, 36.4 years) free of prior diagnosis of CAD.

Results: Controlling traditional risk factors, we found behavioral measures of affiliation (low warmth) accounted for 6.2% of variance in CAC for women, p < .01, but not for men. Controlling behavior (dominance) accounted for 6.0% of variance in CAC for men, p < .02, but not for women. Behavioral measures were related to self-reports of marital quality, but the latter were unrelated to CAC. History of divorce predicted CAC for men and women.

Conclusions: History of divorce and behavioral--but not self-report--measures of marital quality were related to CAD, such that low warmth and high dominance conferred risk for women and men, respectively. Prior research might underestimate the role of marital quality in CAD by relying on global self-reports of this risk factor.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PSY.0b013e31821188caDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4560492PMC
May 2011

Computed Tomography Angiography in Patients Evaluated for Acute Pulmonary Embolism with Low Serum D-dimer Levels: A Prospective Study.

Perm J 2009 ;13(4):4-10

Lana Hirai Gimber, MPH, is a fourth-year medical student at the John A Burns School of Medicine in Honolulu, HI. E-mail: .

Context: Pulmonary computed tomography angiography (CTA) and the Wells criteria both have interobserver variability in the assessment of pulmonary embolism (PE). Quantitative D-dimer assay findings have been shown to have a high negative predictive value in patients with low pretest probability of PE.

Objective: Evaluate roles for clinical probability and CTA in Emergency Department (ED) patients suspected of acute PE but having a low serum D-dimer level.

Design: Prospective observational study of ED patients with possible PE who underwent pulmonary CTA and had D-dimer levels
Main Outcome: Clinical probability of PE determined by ED physicians using standard published criteria; pulmonary CTAs read by initial and study radiologists kept unaware of D-dimer results.

Results: In 16 months, 744 patients underwent pulmonary CTA, with 347 study participants who had a D-dimer level
Conclusion: Pulmonary CTA findings positive for acute embolism should be viewed with caution, especially if the suspected PE is in a distal segmental or subsegmental artery in a patient with a serum D-dimer level of
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7812/tpp/09-060DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2911823PMC
July 2011

Associations of self-reports versus spouse ratings of negative affectivity, dominance, and affiliation with coronary artery disease: where should we look and who should we ask when studying personality and health?

Health Psychol 2008 Nov;27(6):676-84

Department of Psychology, University of Utah, Salt Lake City, UT 84112, USA.

Objective: Aspects of negative affect and social behavior studied as risk factors for coronary heart disease are usually examined separately and through self-reports. Using structural models of these personality domains, we tested associations of self-reports and spouse ratings of anxiety, depressive symptoms, anger, affiliation and dominance with coronary artery disease (CAD).

Design: In 154 healthy older couples, the authors tested cross-sectional associations with CAD of three facets of negative affectivity and two dimensions of the Interpersonal Circumplex, (IPC) using scales derived from the NEO-PI-R.

Main Outcome Measures: CAD was quantified as Agatston scores from CT scans of coronary artery calcification (CAC).

Results: Self-reports were generally unrelated to CAC, whereas spouse ratings were consistently associated, largely independent of potential confounds. When considered simultaneously, anxiety and anger were related to CAC but depression was not. When considered together, both dominance and (low) affiliation were related to CAC.

Conclusions: Structural models of negative affectivity and social behavior can facilitate integrative study of psychosocial risk factors. Further, self-report measures of these traits might under-estimate related CHD risk.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1037/0278-6133.27.6.676DOI Listing
November 2008

On the mechanism of action of pneumatic compression devices: Combined magnetic resonance imaging and duplex ultrasound investigation.

J Vasc Surg 2008 Oct 24;48(4):1000-6. Epub 2008 Jun 24.

John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii; Kistner Vein Clinic, Honolulu, Hawaii.

Objective: This study investigated the relationships between the interface pressure produced by intermittent pneumatic compression (IPC) devices, the deformation of extremity tissues produced by this pressure, and changes in venous blood flow associated with this deformation by use of magnetic resonance imaging (MRI) and duplex ultrasound (DUS) imaging in addition to the pressure measurement.

Methods: The calf garments of two IPC devices (WizAir, Medical Compression Systems, Inc, Ltd, Or-Akiva, Israel; VenaFlow, AirCast Inc, Summit, NJ) were tested in five healthy volunteers. The interface pressure was measured with Tactilus Human Body Interface sensor system (Sensor Products Inc, Madison, NJ). Changes in tissue volumes were assessed with MRI. Velocity and flow changes in the great saphenous vein (GSV) and femoral veins (FV) were evaluated by DUS scans.

Results: The spatial distribution of interface pressure differed substantially between the two devices. These differences were in the location and percentage of calf surface area to which different pressure was applied. Both devices produced the tissue compression consistent with each device's unique pattern of the interface pressure distribution. Compression by the IPC devices was associated with a measurable decrease in the volume of subcutaneous tissue under the garment, the total volume of superficial veins, and the volume of the GSV. No measurable changes occurred in subfascial volume of the calf. Compression was associated with significant increase in flow velocities in the GSV and FV. The increase of volume flow was significant in FV, but not in GSV. Comparing hemodynamic data with MRI data showed that the flow velocity increase in FV and GSV caused by IPC highly correlated with decrease in volume of superficial veins and subcutaneous tissue measured by MRI, but not with changes in subfascial volume. A single strongest predictor of venous flow increase was the change in subcutaneous veins volume.

Conclusions: This methodology provides means for the investigation of relationships between the pressure in the garment, interface pressure, tissue deformation, and hemodynamic respond to IPC. The clinical efficacy of IPC should not be explicitly attributed to the magnitude of the pressure in the garment. Similar hemodynamic responses to IPC can be produced by different spatial distributions of pressure resulting in different patterns of tissue compression. Further investigation of biomechanical mechanisms of IPC is needed to guide the development of better engineering solutions for mechanical devices aimed at prevention of venous thrombosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jvs.2008.04.009DOI Listing
October 2008

Randomized prospective comparison of alteplase versus saline solution for the percutaneous treatment of loculated abdominopelvic abscesses.

J Vasc Interv Radiol 2008 Jun 25;19(6):906-11. Epub 2008 Apr 25.

John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, USA.

Purpose: To determine if alteplase infusion for the treatment of loculated abdominopelvic abscesses requiring percutaneous catheter drainage was superior to saline solution infusion.

Methods And Materials: This study was a single-center prospective randomized trial. Patients with loculated abdominopelvic abscesses unsuccessfully drained by initial catheter placement were randomized to receive the fibrinolytic agent alteplase or normal saline solution. The amount of alteplase used to treat abscesses was 2 mg or 4 mg based on infusion volumes of 0-50 mL or 51-100 mL, respectively. Infusions were administered twice daily for 3 days. Computed tomography was performed before initiation of therapy and immediately after 3 days of infusions. Success was defined by removal of the catheter after drainage without recurrent abscess or surgical intervention within 30 days.

Results: A total of 20 patients were included in this study: 11 received alteplase and nine received normal saline solution. There was no significant difference in the distribution of sex (P = .08) or age (P = .29). Abscess resolution was achieved in nine of 11 alteplase-treated patients (80%) versus three of nine saline solution-treated patients (33%). However, one patient in each group required repeat intervention within 30 days, for overall success rates of 73% versus 22%, respectively (P = .02). Having observed a significant difference in the primary outcome variable, the study was terminated early.

Conclusions: A 3-day course of twice-daily alteplase infusion therapy is superior to normal saline solution for the treatment of loculated abdominopelvic abscesses.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jvir.2008.03.007DOI Listing
June 2008

CT angiography of the superior vena cava: normative values and implications for central venous catheter position.

J Vasc Interv Radiol 2007 Sep;18(9):1106-10

Department of Radiology, Tripler Army Medical Center, Honolulu, Hawaii, USA.

Purpose: To determine normative data for radiographic landmarks of the superior vena cava (SVC) and the location of the junction of the SVC with the right atrium for use in the placement of central venous catheters.

Materials And Methods: The authors retrospectively reviewed 112 pulmonary computed tomographic (CT) angiograms obtained in seven men and seven women from each decade of life between the ages of 20 and 99 years. For each patient, the length of the SVC was measured from its origin to the cavoatrial junction. The distances from the carina and right tracheobronchial angle to the cavoatrial junction and the origin of the SVC were also measured. Interobserver variation in choosing the location of the carina and tracheobronchial angle was analyzed.

Results: The mean length (+/-standard deviation) of the SVC was 70.7 mm +/- 14.1. The mean distance from the superior margin of the SVC to the carina was 30.4 mm +/- 11.2, from the carina to the cavoatrial junction 40.3 mm +/- 13.6, from the superior margin of the SVC to the right tracheobronchial angle 21.7 mm +/- 10.8, and from the right tracheobronchial angle to the cavoatrial junction 49.0 mm +/- 13.6. There was a statistically significant difference in interobserver variation in selecting the location of the right tracheobronchial angle as compared to choosing the carina.

Conclusion: Placement of the central venous catheter tip at or just below the level of the carina during inspiration ensures placement in the SVC. Placement of the central venous catheter tip approximately 4 cm below the carina will result in placement near the cavoatrial junction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jvir.2007.06.002DOI Listing
September 2007

A prospective evaluation of a quantitative D-dimer assay in the evaluation of acute pulmonary embolism.

J Vasc Interv Radiol 2007 Aug;18(8):970-4

John A. Burns School of Medicine, Kaiser Foundation Hospital, 3288 Moanalua Road, Honolulu, Hawaii 96819, USA.

Purpose: A prospective study was designed to determine if a screening quantitative serum D-dimer measurement of 1.0 microg/mL or less precludes pulmonary computed tomographic (CT) angiography in patients with possible acute pulmonary embolism (PE).

Materials And Methods: Over a period of 16 months, every patient seen in the emergency department in whom there was clinical suspicion of PE sufficient to warrant pulmonary CT angiography was also requested to have a quantitative serum D-dimer level measurement taken. All pulmonary CT angiography procedures were performed on a four-slice scanner and every examination was overread by a radiologist who was blinded to the D-dimer assay results. Three-month medical record and telephone follow-up was carried out for all participants who had a serum D-dimer level of 1.0 microg/mL or less to verify no new diagnosis or death from PE.

Results: In this prospective study, 361 consecutive patients who received pulmonary CT angiography had a D-dimer level of 1.0 microg/mL or less. There were 310 patients who had negative pulmonary CT angiography results and 50 patients who had indeterminate CT angiography results. Only one patient had positive pulmonary CT angiography findings. Minimum 3-month follow-up information was available for 349 patients, none of whom reported subsequent PE, including those with indeterminate pulmonary CT angiography results.

Conclusion: The use of a screening D-dimer measurement of 1.0 microg/mL or less precludes pulmonary CT angiography in patients with possible acute PE. The use of this quantitative D-dimer assay would decrease radiation exposure, contrast medium toxicity, cost, and time for patients seen in the emergency medicine department.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jvir.2007.04.020DOI Listing
August 2007

Hostile personality traits and coronary artery calcification in middle-aged and older married couples: different effects for self-reports versus spouse ratings.

Psychosom Med 2007 Jun;69(5):441-8

Department of Psychology, University of Utah, Salt Lake City, UT 84112-0251, USA.

Objective: To examine the association between hostile personality traits and coronary artery disease (CAD) and the role of aspects of hostility, method of assessment, and age as influences on its magnitude, as prior studies of hostility and coronary artery calcification (CAC) have produced conflicting findings.

Methods: Participants included 300 married couples (mean age = 54.4 years) free from diagnosed CAD. Participants completed four measures of hostility-self-reports and spouse ratings of angry hostility (i.e., tendency to experience anger) and antagonism (i.e., argumentative, mistrusting, and cold interpersonal behavior).

Results: In hierarchical random regression models accounting for dependency between husbands' and wives' observations, analyses of log-transformed Agatston scores indicated that self-reports of angry hostility and antagonism were not related to CAC. However, spouse ratings of both anger and antagonism were significantly associated with CAC severity. Interactions with age indicated that these associations occurred only among older participants. Control of behavioral and biomedical risk factors did not eliminate these effects. Antagonism but not anger was an independent predictor of CAC when considered simultaneously.

Conclusions: Hostility is associated with concurrent asymptomatic CAD as assessed through CAC, but this effect is likely to be underestimated when hostility is assessed through self-reports rather than ratings by others and in samples with lower prevalence and severity of CAC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PSY.0b013e3180600a65DOI Listing
June 2007

SIR 2004 film panel case: Primary hyperoxaluria type I mimicking arterial vasculitis--a lethal disease.

J Vasc Interv Radiol 2004 Sep;15(9):1017-20

Department of Radiology, University of Utah, 50 North Medical Drive, Salt Lake City, UT 84132, USA.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/01.RVI.0000135866.37203.50DOI Listing
September 2004

Role of a quantitative D-dimer assay in determining the need for CT angiography of acute pulmonary embolism.

AJR Am J Roentgenol 2004 Jun;182(6):1377-81

Department of Diagnostic Imaging, Kaiser Foundation Hospital, 3288 Moanalua Rd., Honolulu, HI 96814, USA.

Objective: Our goal was to use the results of a quantitative D-dimer assay to determine the need for pulmonary CT angiography in patients suspected of having acute pulmonary embolism.

Materials And Methods: From July 2001 to December 2002, 755 patients underwent pulmonary CT angiography for the evaluation of acute pulmonary embolism. A rapid, fully automated quantitative D-dimer assay was obtained in more than half the patients. The electronic medical records of the patients were subsequently reviewed to analyze the negative predictive value of the D-dimer assay in the diagnostic workup of acute pulmonary embolism and to determine the outcome of the patients who had negative findings on both D-dimer assay and pulmonary CT angiography at 3-month follow-up.

Results: Of the 755 patients who underwent pulmonary CT angiography, 666 (88.2%) had negative findings, 73 (9.7%) had positive findings, and 16 (2.1%) were indeterminate. A total of 426 patients underwent both pulmonary CT angiography and D-dimer level evaluation, and 84 of these had negative findings (< 0.4 microg/mL) on D-dimer assay. Eighty-two of the 84 patients with negative findings on D-dimer assay had negative findings on pulmonary CT angiography; two were indeterminate and both subsequently had low-probability ventilation-perfusion studies. Among patients with positive D-dimer assays, no one with a level between 0.4 and 1.0 microg/mL had pulmonary CT angiography with findings positive for pulmonary embolism.

Conclusion: A quantitative D-dimer assay was effective in excluding the need for pulmonary CT angiography and had high negative predictive value when the D-dimer level was less than 1.0 microg/mL.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2214/ajr.182.6.1821377DOI Listing
June 2004

Intense inflammatory reaction to heparin polymer coated intravascular Palmaz stents in porcine arteries compared to uncoated Palmaz stents.

Cardiovasc Intervent Radiol 2003 Mar-Apr;26(2):158-67. Epub 2003 Mar 6.

Department of Radiology, Veterans Administration, Los Angeles, CA 90073, USA.

The objective of this study was to evaluate the efficacy of heparin-polymer-coated intravascular stents in the reduction of vessel stenosis. Three types of coatings for Palmaz stents were tested: 1) heparin covalently bound to a polyethylene oxide (Hp-PEO) tether; 2) heparin copolymerized with ethylene vinyl acetate (Hp-Elvax) and 3) Elvax alone. Polymer-coated stents and uncoated controls were deployed in the external iliac arteries following endothelial injury in 18 swine. The animals were maintained on an atherogenic diet and examined by angiography at 6 and 12 weeks. The stented segments were then harvested for histopathologic analysis. Both types of heparin-coated stents resulted in increased luminal narrowing as compared to the contralateral uncoated stents. At 6 weeks, average luminal stenosis was 48% for Hp-PEO stents vs 35% for uncoated stents (p <0.05). At 12 weeks, average luminal stenosis was 36% for Hp-PEO stents vs 26% for uncoated stents (p = NS). For Hp-Elvax stents, the average stenosis was 58% vs 33% for uncoated controls (p < 0.05) at 6 weeks and 47% vs 19% for uncoated controls (p <0.05) at 12 weeks. There was no significant difference between Hp-Elvax stents and Elvax stents (p = NS). Increased luminal narrowing in coated stents was primarily secondary to a marked inflammatory response. Heparin-polyethylene oxide and heparin-ethylene vinyl acetate-coated stents resulted in increased luminal narrowing as compared with uncoated stents, due to a marked inflammatory response.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00270-002-2562-0DOI Listing
December 2003

Progression of coronary artery calcification in patients taking alendronate for osteoporosis.

Acad Radiol 2002 Oct;9(10):1148-52

Department of Radiological Sciences, UCLA School of Medicine, Los Angeles, Calif 90048, USA.

Rationale And Objectives: As with their actions on bone, bisphosphonates may play a role in coronary artery calcification (CAC) by inhibiting calcium resorption from plaque. The objective of this study was to determine whether the osteoporosis treatment agent alendronate accelerates the rate of CAC.

Materials And Methods: The study was a pilot comparative analysis of 56 alendronate-treated patients with osteoporosis compared with 56 control subjects matched for age, sex, risk factors, and CAC scores and with a reference cohort that included 213 control subjects. Patients received alendronate sodium (10 mg daily) for a mean of 24 months and underwent annual assessment of CAC with electron-beam computed tomography and bone mineral density with dual x-ray absorptiometry. The principal outcome measure was the rate of change in CAC score in patients and control populations.

Results: There was significant progression of CAC in both alendronate-treated and matched-control groups (paired t test, P = .004 and .006, respectively) but no difference in the rates of CAC progression between the alendronate-treated patients and either the matched or reference control cohort.

Conclusions: This small pilot study indicates that oral alendronate administration does not accelerate the rate of CAC, but a larger cohort should be studied to confirm these findings.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/s1076-6332(03)80516-0DOI Listing
October 2002

Calcium begets calcium: progression of coronary artery calcification in asymptomatic subjects.

Radiology 2002 Jul;224(1):236-41

Department of Diagnostic Imaging, Kaiser Moanalua Medical Center, 3288 Moanalua Rd, Honolulu, HI 96819, USA.

Purpose: To test the hypothesis that the rate of coronary artery calcium progression is sex specific, namely, that it is greater in men than in women, and that it is age related, particularly in women.

Materials And Methods: This was a retrospective study of the progression of coronary artery calcium in 217 consecutive asymptomatic subjects who underwent at least two electron-beam computed tomographic studies of the heart. Calcium in the distribution of the epicardial arteries was quantified by using both the conventional coronary artery calcium score (CCS) and the calcium volume score (CVS). Linear regression models were used to judge the joint influence of various risk factors, including sex and age, on rates of coronary artery calcium progression.

Results: This study included 103 women and 114 men. The mean interval between the subjects' first and last studies was 25 months +/- 11 (SD). Regression analyses clearly demonstrated that the amount of coronary artery calcium present at the initial study was the most important determinant of calcium progression. This was true when coronary artery calcium was quantified by using the conventional CCS (P <.001) or CVS (P <.001). Neither sex nor age was a significant predictor of coronary artery calcium progression. Among traditional risk factors, only hypertension (P =.02) and diabetes (P =.01) were significant independent factors for calcium progression.

Conclusion: In asymptomatic subjects, the initial CCS and CVS were the most important factors that affected rate of coronary artery calcium progression. Neither age nor sex was as important as these factors in determination of coronary artery calcium progression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1148/radiol.2241011191DOI Listing
July 2002

Using a peptide inhibitor of the glycoprotein IIb/IIIa platelet receptor: initial experience in patients with acute peripheral arterial occlusions.

AJR Am J Roentgenol 2002 Mar;178(3):617-22

Department of Radiology, University of Utah School of Medicine, 1A-71 SOM, 50 N. Medical Dr., Salt Lake City, UT 84132, USA.

Objective: The purpose of this study was to evaluate the efficacy of eptifibatide, an inhibitor of the glycoprotein (GP) IIb/IIIa platelet receptor, in the thrombolytic treatment of patients with acute peripheral arterial occlusive disease.

Materials And Methods: We retrospectively reviewed our experience with the use of a GP IIb/IIIa receptor inhibitor, eptifibatide, during thrombolysis in 17 patients with acute lower extremity arterial occlusions who also received intraarterial recombinant tissue plasminogen activator (rt-PA) and heparin. Four of the 17 patients received their loading dose of eptifibatide by direct intraarterial injection, whereas the remaining 13 received an IV loading dose. We compared their results with those of 11 other patients who received only rt-PA and heparin with respect to success and complication rates, duration of thrombolytic therapy, and total rt-PA dose.

Results: We found no significant difference in successful outcome (p = 1.00), major complications (p = 1.00), duration of therapy (p = 0.21), or total rt-PA dose (p = 0.67) between those who received eptifibatide and those who did not during thrombolytic therapy. However, those patients who received an intraarterial loading dose of eptifibatide required substantially less rt-PA (9.0 +/- 4.4 mg vs 38.9 +/- 30.7 mg) to achieve successful thrombolysis.

Conclusion: The adjunctive use of a GP IIb/IIIa platelet receptor inhibitor during thrombolysis for arterial occlusions may decrease the total dose of rt-PA required for thrombolysis without compromising success or complication rates. A prospective randomized study is needed to confirm that inhibitors of the GP IIb/IIIa platelet receptor can facilitate thrombolytic therapy in patients with acute lower extremity arterial occlusions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2214/ajr.178.3.1780617DOI Listing
March 2002
-->