Publications by authors named "Ashley Prosper"

16 Publications

  • Page 1 of 1

Temporally aware volumetric generative adversarial network-based MR image reconstruction with simultaneous respiratory motion compensation: Initial feasibility in 3D dynamic cine cardiac MRI.

Magn Reson Med 2021 Jul 13. Epub 2021 Jul 13.

Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, California, USA.

Purpose: Develop a novel three-dimensional (3D) generative adversarial network (GAN)-based technique for simultaneous image reconstruction and respiratory motion compensation of 4D MRI. Our goal was to enable high-acceleration factors 10.7X-15.8X, while maintaining robust and diagnostic image quality superior to state-of-the-art self-gating (SG) compressed sensing wavelet (CS-WV) reconstruction at lower acceleration factors 3.5X-7.9X.

Methods: Our GAN was trained based on pixel-wise content loss functions, adversarial loss function, and a novel data-driven temporal aware loss function to maintain anatomical accuracy and temporal coherence. Besides image reconstruction, our network also performs respiratory motion compensation for free-breathing scans. A novel progressive growing-based strategy was adapted to make the training process possible for the proposed GAN-based structure. The proposed method was developed and thoroughly evaluated qualitatively and quantitatively based on 3D cardiac cine data from 42 patients.

Results: Our proposed method achieved significantly better scores in general image quality and image artifacts at 10.7X-15.8X acceleration than the SG CS-WV approach at 3.5X-7.9X acceleration (4.53 ± 0.540 vs. 3.13 ± 0.681 for general image quality, 4.12 ± 0.429 vs. 2.97 ± 0.434 for image artifacts, P < .05 for both). No spurious anatomical structures were observed in our images. The proposed method enabled similar cardiac-function quantification as conventional SG CS-WV. The proposed method achieved faster central processing unit-based image reconstruction (6 s/cardiac phase) than the SG CS-WV (312 s/cardiac phase).

Conclusion: The proposed method showed promising potential for high-resolution (1 mm ) free-breathing 4D MR data acquisition with simultaneous respiratory motion compensation and fast reconstruction time.
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http://dx.doi.org/10.1002/mrm.28912DOI Listing
July 2021

Slice encoding for the reduction of outflow signal artifacts in cine balanced SSFP imaging.

Magn Reson Med 2021 Oct 31;86(4):2034-2048. Epub 2021 May 31.

Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, USA.

Purpose: Standard balanced SSFP (bSSFP) cine MRI often suffers from blood outflow artifacts. We propose a method that spatially encodes these outflowing spins to reduce their effects in the intended slice.

Methods: Bloch simulations were performed to characterize through-plane flow and to investigate how the use of phase encoding along the slice select's direction ("slice encoding") could alleviate its issues. Phantom scans and in vivo cines were acquired on a 3T system, comparing the standard 2D acquisition to the proposed slice-encoding method. Nineteen healthy volunteers were recruited for short-axis and horizontal long-axis oriented scans. An expert radiologist evaluated each slice-encoded/standard cine pairs in a rank comparison test and graded their quality on a 1-5 scale. The grades were used for a nonparametric paired evaluation for independent samples with a null hypothesis that there was no statistical difference between the two quality-grade distributions for α = 0.05 significance.

Results: Bloch simulation results demonstrated this technique's feasibility, showing a fully resolved slice profile given a sufficient number of slice encodes. These results were confirmed with the phantom experiments. Each in vivo slice-encoded cine had a higher quality than its corresponding standard acquisition. The nonparametric paired evaluation came to 0.01 significance, encouraging us to reject the null hypothesis and conclude that slice-encoding effectively works in reducing outflow effects.

Conclusion: The slice-encoding balanced SSFP technique is helpful in mitigating outflow effects and is achievable within a single breath hold, being a useful alternative for cases in which the flow artifacts are significant.
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http://dx.doi.org/10.1002/mrm.28858DOI Listing
October 2021

Right Ventricular Function and T1-Mapping in Boys With Duchenne Muscular Dystrophy.

J Magn Reson Imaging 2021 May 26. Epub 2021 May 26.

Department of Radiology, Stanford University, Palo Alto, California, USA.

Background: Clinical management of boys with Duchenne muscular dystrophy (DMD) relies on in-depth understanding of cardiac involvement, but right ventricular (RV) structural and functional remodeling remains understudied.

Purpose: To evaluate several analysis methods and identify the most reliable one to measure RV pre- and postcontrast T1 (RV-T1) and to characterize myocardial remodeling in the RV of boys with DMD.

Study Type: Prospective.

Population: Boys with DMD (N = 27) and age-/sex-matched healthy controls (N = 17) from two sites.

Field Strength/sequence: 3.0 T using balanced steady state free precession, motion-corrected phase sensitive inversion recovery and modified Look-Locker inversion recovery sequences.

Assessment: Biventricular mass (Mi), end-diastolic volume (EDVi) and ejection fraction (EF) assessment, tricuspid annular excursion (TAE), late gadolinium enhancement (LGE), pre- and postcontrast myocardial T1 maps. The RV-T1 reliability was assessed by three observers in four different RV regions of interest (ROI) using intraclass correlation (ICC).

Statistical Tests: The Wilcoxon rank sum test was used to compare RV-T1 differences between DMD boys with negative LGE(-) or positive LGE(+) and healthy controls. Additionally, correlation of precontrast RV-T1 with functional measures was performed. A P-value <0.05 was considered statistically significant.

Results: A 1-pixel thick RV circumferential ROI proved most reliable (ICC > 0.91) for assessing RV-T1. Precontrast RV-T1 was significantly higher in boys with DMD compared to controls. Both LGE(-) and LGE(+) boys had significantly elevated precontrast RV-T1 compared to controls (1543 [1489-1597] msec and 1550 [1402-1699] msec vs. 1436 [1399-1473] msec, respectively). Compared to healthy controls, boys with DMD had preserved RVEF (51.8 [9.9]% vs. 54.2 [7.2]%, P = 0.31) and significantly reduced RVMi (29.8 [9.7] g vs. 48.0 [15.7] g), RVEDVi (69.8 [29.7] mL/m vs. 89.1 [21.9] mL/m ), and TAE (22.0 [3.2] cm vs. 26.0 [4.7] cm). Significant correlations were found between precontrast RV-T1 and RVEF (β = -0.48%/msec) and between LV-T1 and LVEF (β = -0.51%/msec).

Data Conclusion: Precontrast RV-T1 is elevated in boys with DMD compared to healthy controls and is negatively correlated with RVEF.

Level Of Evidence: 1 TECHNICAL EFFICACY: Stage 2.
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http://dx.doi.org/10.1002/jmri.27729DOI Listing
May 2021

Pulmonary vein and left atrial posterior wall isolation for the treatment of atrial fibrillation: Comparable outcomes for adults with congenital heart disease.

J Cardiovasc Electrophysiol 2021 Jul 14;32(7):1868-1876. Epub 2021 Apr 14.

UCLA Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, California, USA.

Introduction: Optimal treatment strategies for ACHD with AF are unknown. This study sought to assess outcomes of pulmonary vein isolation (PVI) ± left atrial (LA), posterior wall isolation (PWI) for adults with congenital heart disease (ACHD), and atrial fibrillation (AF).

Methods: A retrospective review of all cryoballoon (CB) PVI ± PWI procedures at a single center over a 3-year period were performed. Clinical characteristics and outcomes for patients with and without ACHD were compared. The primary outcome was the occurrence of atrial tachyarrhythmia at 12-months postablation after a 90-day blanking period.

Results: Three-hundred and sixteen patients (mean: 63 ± 12 years, [63% male]) underwent CB PVI ± PWI during the study, including 31 (10%) ACHD (simple 35%, moderate 39% complex 26%; nonparoxysmal AF in 52%). ACHD was younger (51 vs. 64 years; p < .001) with a lower CHADS DS -VASc score (1.2 vs. 2.1; p = .001) but had a greater LA diameter (4.9 vs. 4.0 cm; p < .001) and a number of prior cardioversions (0.9 vs. 0.4; p < .001) versus controls. 12-month freedom from recurrent AF was similar for ACHD and controls (76% vs. 80%; p = .6) and remained nonsignificant in multivariate analysis (hazard ratio: 1.8, 95% confidence interval: 0.7-5.1; p = .22). At 12-months postablation, 75% of ACHD versus 93% of control patients were off antiarrhythmic drug therapy (p = .07).

Conclusion: This study demonstrates younger age and lower conventional stroke risk, yet clinically advanced AF for ACHD relative to controls. CB PVI ± PWI was an effective strategy for the treatment of AF among all forms of ACHD with similar 12-month outcomes as compared to controls.
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http://dx.doi.org/10.1111/jce.15027DOI Listing
July 2021

Lung Cancer Screening in African Americans: The Time to Act Is Now.

Radiol Imaging Cancer 2020 09 21;2(5):e200107. Epub 2020 Aug 21.

Department of Radiological Sciences, David Geffen School of Medicine at UCLA, Los Angeles, Calif (A.P., K.B., B.S., D.A.); and Department of Radiology, Ronald Reagan UCLA Medical Center, Los Angeles, Calif (B.S.).

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http://dx.doi.org/10.1148/rycan.2020200107DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7983712PMC
September 2020

T-Mapping and extracellular volume estimates in pediatric subjects with Duchenne muscular dystrophy and healthy controls at 3T.

J Cardiovasc Magn Reson 2020 12 10;22(1):85. Epub 2020 Dec 10.

Department of Radiology, Stanford University, 1201 Welch Road, Room P264, Stanford, CA, 94305-5488, USA.

Background: Cardiovascular disease is the leading cause of death in patients with Duchenne muscular dystrophy (DMD)-a fatal X-linked genetic disorder. Late gadolinium enhancement (LGE) imaging is the current gold standard for detecting myocardial tissue remodeling, but it is often a late finding. Current research aims to investigate cardiovascular magnetic resonance (CMR) biomarkers, including native (pre-contrast) T and extracellular volume (ECV) to evaluate the early on-set of microstructural remodeling and to grade disease severity. To date, native T measurements in DMD have been reported predominantly at 1.5T. This study uses 3T CMR: (1) to characterize global and regional myocardial pre-contrast T differences between healthy controls and LGE + and LGE- boys with DMD; and (2) to report global and regional myocardial post-contrast T values and myocardial ECV estimates in boys with DMD, and (3) to identify left ventricular (LV) T-mapping biomarkers capable of distinguishing between healthy controls and boys with DMD and detecting LGE status in DMD.

Methods: Boys with DMD (N = 28, 13.2 ± 3.1 years) and healthy age-matched boys (N = 20, 13.4 ± 3.1 years) were prospectively enrolled and underwent a 3T CMR exam including standard functional imaging and T mapping using a modified Look-Locker inversion recovery (MOLLI) sequence. Pre-contrast T mapping was performed on all boys, but contrast was administered only to boys with DMD for post-contrast T and ECV mapping. Global and segmental myocardial regions of interest were contoured on mid LV T and ECV maps. ROI measurements were compared for pre-contrast myocardial T between boys with DMD and healthy controls, and for post-contrast myocardial T and ECV between LGE + and LGE- boys with DMD using a Wilcoxon rank-sum test. Results are reported as median and interquartile range (IQR). p-Values < 0.05 were considered significant. Receiver Operating Characteristic analysis was used to evaluate a binomial logistic classifier incorporating T mapping and LV function parameters in the tasks of distinguishing between healthy controls and boys with DMD, and detecting LGE status in DMD. The area under the curve is reported.

Results: Boys with DMD had significantly increased global native T [1332 (60) ms vs. 1289 (56) ms; p = 0.004] and increased within-slice standard deviation (SD) [100 (57) ms vs. 74 (27) ms; p = 0.001] compared to healthy controls. LGE- boys with DMD also demonstrated significantly increased lateral wall native T [1322 (68) ms vs. 1277 (58) ms; p = 0.001] compared to healthy controls. LGE + boys with DMD had decreased global myocardial post-contrast T [565 (113) ms vs 635 (126) ms; p = 0.04] and increased global myocardial ECV [32 (8) % vs. 28 (4) %; p = 0.02] compared to LGE- boys. In all classification tasks, T-mapping biomarkers outperformed a conventional biomarker, LV ejection fraction. ECV was the best performing biomarker in the task of predicting LGE status (AUC = 0.95).

Conclusions: Boys with DMD exhibit elevated native T compared to healthy, sex- and age-matched controls, even in the absence of LGE. Post-contrast T and ECV estimates from 3T CMR are also reported here for pediatric patients with DMD for the first time and can distinguish between LGE + from LGE- boys. In all classification tasks, T-mapping biomarkers outperform a conventional biomarker, LVEF.
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http://dx.doi.org/10.1186/s12968-020-00687-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7731511PMC
December 2020

Retrospective respiratory motion correction in cardiac cine MRI reconstruction using adversarial autoencoder and unsupervised learning.

NMR Biomed 2021 02 30;34(2):e4433. Epub 2020 Nov 30.

Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, California, USA.

The aim of this study was to develop a deep neural network for respiratory motion compensation in free-breathing cine MRI and evaluate its performance. An adversarial autoencoder network was trained using unpaired training data from healthy volunteers and patients who underwent clinically indicated cardiac MRI examinations. A U-net structure was used for the encoder and decoder parts of the network and the code space was regularized by an adversarial objective. The autoencoder learns the identity map for the free-breathing motion-corrupted images and preserves the structural content of the images, while the discriminator, which interacts with the output of the encoder, forces the encoder to remove motion artifacts. The network was first evaluated based on data that were artificially corrupted with simulated rigid motion with regard to motion-correction accuracy and the presence of any artificially created structures. Subsequently, to demonstrate the feasibility of the proposed approach in vivo, our network was trained on respiratory motion-corrupted images in an unpaired manner and was tested on volunteer and patient data. In the simulation study, mean structural similarity index scores for the synthesized motion-corrupted images and motion-corrected images were 0.76 and 0.93 (out of 1), respectively. The proposed method increased the Tenengrad focus measure of the motion-corrupted images by 12% in the simulation study and by 7% in the in vivo study. The average overall subjective image quality scores for the motion-corrupted images, motion-corrected images and breath-held images were 2.5, 3.5 and 4.1 (out of 5.0), respectively. Nonparametric-paired comparisons showed that there was significant difference between the image quality scores of the motion-corrupted and breath-held images (P < .05); however, after correction there was no significant difference between the image quality scores of the motion-corrected and breath-held images. This feasibility study demonstrates the potential of an adversarial autoencoder network for correcting respiratory motion-related image artifacts without requiring paired data.
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http://dx.doi.org/10.1002/nbm.4433DOI Listing
February 2021

Left atrial thrombus mimicking myxoma in a patient with hereditary hemorrhagic telangiectasia: Diagnostic and therapeutic dilemmas.

Radiol Case Rep 2020 Oct 18;15(10):1909-1914. Epub 2020 Aug 18.

Division of Cardiology, Department of Medicine, University of California Los Angeles, 650 Charles E. Young Drive South, A2-237 CHS, Los Angeles, CA 90095, USA.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by the development of arteriovenous malformations. The arteriovenous shunts may result in high output heart failure, which predisposes to atrial dilatation and atrial fibrillation. Due to recurrent bleeding from epistaxis or the gastrointestinal tract, patients with HHT and atrial fibrillation are at high risk of bleeding if anticoagulated for stroke prevention. In this report, we present a case of a 74-year-old woman with a history of HHT and atrial fibrillation who developed a large left atrial thrombus that initially was thought to represent an atrial myxoma. The diagnosis was confirmed with cardiac magnetic resonance imaging, and the patient underwent surgical resection of the thrombus. This case demonstrates the role of different imaging modalities in the assessment of left atrial masses and presents an opportunity to review the data on safety of anticoagulation in patients with HHT.
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http://dx.doi.org/10.1016/j.radcr.2020.07.050DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7452037PMC
October 2020

Recent Innovations in Renal Vascular Imaging.

Radiol Clin North Am 2020 Jul 11;58(4):781-796. Epub 2020 May 11.

Department of Radiological Sciences, Thoracic and Diagnostic Cardiovascular Imaging, David Geffen School Medicine, University of California Los Angeles (UCLA), 10945 Le Conte Avenue, Suite 3371, Los Angeles, CA 90095, USA.

Noninvasive imaging of the vascular renal system is a common request in diagnostic radiology. Typical indications include suspected renovascular hypertension, vasculitis, neoplasm, vascular malformation, and structural diseases of the kidney. Profound knowledge of the renal anatomy, including vascular supply and variants, is mandatory for radiologists and allows for optimized protocolling and interpretation of imaging studies. Besides renal ultrasound, computed tomography and MR imaging are commonly requested cross-sectional studies for renal and renal vascular imaging. This article discusses basic renal vascular anatomy, common imaging findings, and current and potential future imaging protocols for various renovascular pathologic conditions.
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http://dx.doi.org/10.1016/j.rcl.2020.02.010DOI Listing
July 2020

Left Atrial Appendage Mechanical Exclusion: Procedural Planning Using Cardiovascular Computed Tomographic Angiography.

J Thorac Imaging 2020 Jul;35(4):W107-W118

Radiology, University of Southern California Keck School of Medicine, Los Angeles, CA.

Left atrial appendage (LAA) mechanical exclusion is being investigated for nonpharmacologic stroke risk reduction in selected patients with atrial fibrillation. There are multiple potential approaches in various stages of development and clinical application, each of which depends on specific cardiothoracic anatomic characteristics for optimal performance. Multiple imaging modalities can be utilized for application of this technology, with transesophageal echocardiography used for intraprocedural guidance. Cardiovascular computed tomographic angiography can act as a virtual patient avatar, allowing for the assessment of cardiac structures in the context of surrounding cardiac, coronary vascular, thoracic vascular, and visceral and skeletal anatomy, aiding preprocedural decision-making, planning, and follow-up. Although transesophageal echocardiography is used for intraprocedural guidance, computed tomographic angiography may be a useful adjunct for preprocedure assessment of LAA sizing and anatomic obstacles or contraindications to deployment, aiding in the assessment of optimal approaches. Potential approaches to LAA exclusion include endovascular occlusion, epicardial ligation, primary minimally invasive intercostal thoracotomy with thoracoscopic LAA ligation or appendectomy, and minimally invasive or open closure as part of cardiothoracic surgery for other indications. The goals of these procedures are complete isolation or exclusion of the entire appendage without leaving a residual appendage stump or residual flow with avoidance of acute or chronic damage to surrounding cardiovascular structures. The cardiovascular imager plays an important role in the preprocedural and postprocedural assessment of the patient undergoing LAA exclusion.
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http://dx.doi.org/10.1097/RTI.0000000000000504DOI Listing
July 2020

Forward-Projected Model-Based Iterative Reconstruction in Screening Low-Dose Chest CT: Comparison With Adaptive Iterative Dose Reduction 3D.

AJR Am J Roentgenol 2018 09 24;211(3):548-556. Epub 2018 Jul 24.

1 Keck Hospital, University of Southern California, 1500 San Pablo St, 2nd Fl Radiology, Los Angeles, CA 90033.

Objective: The objective of this study is to compare forward-projected model-based iterative reconstruction solution (FIRST), a newer fully iterative CT reconstruction method, with adaptive iterative dose reduction 3D (AIDR 3D) in low-dose screening CT for lung cancer. Differences in image noise, image quality, and pulmonary nodule detection, size, and characterization were specifically evaluated.

Materials And Methods: Low-dose chest CT images obtained for 50 consecutive patients between December 2015 and January 2016 were retrospectively reviewed. Images were reconstructed using FIRST and AIDR 3D for both lung and soft-tissue reconstruction. Images were independently reviewed to assess image noise, subjective image quality (with use of a 5-point Likert scale, with 1 denoting far superior image quality; 2, superior quality; 3, equivalent quality; 4, inferior quality; and 5, far inferior quality), pulmonary nodule count, size of the largest pulmonary nodule, and characterization of the largest pulmonary nodule (i.e., solid, part solid, or ground glass).

Results: Across all 50 cases, measured image noise was lower with FIRST than with AIDR 3D (lung window, 44% reduction, 41 ± 7 vs 74 ± 8 HU, respectively; soft-tissue window, 32% reduction, 11 ± 2 vs 16 ± 2 HU, respectively). Readers subjectively rated images obtained with FIRST as comparable to images obtained with AIDR 3D (mean [± SD] Likert score for FIRST vs AIDR 3D, 3.2 ± 0.3 for soft-tissue reconstructions and 3.0 ± 0.3 for lung reconstructions). For each reader, very good agreement regarding nodule count was noted between FIRST and AIDR 3D (interclass correlation coefficient [ICC], 0.83 for reader 1 and 0.78 for reader 2). Excellent agreement regarding nodule size (ICC, 0.99 for reader 1 and 0.99 for reader 2) and characterization of the largest nodule (kappa value, 0.92 for reader 1 and 0.82 for reader 2) also existed.

Conclusion: Images reconstructed with FIRST are superior to those reconstructed AIDR 3D with regard to image noise and are equivalent with regard to subjective image quality, pulmonary nodule count, and nodule characterization.
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http://dx.doi.org/10.2214/AJR.17.19245DOI Listing
September 2018

Myocardial Perfusion SPECT and Cardiac MR Correlative Imaging.

Clin Nucl Med 2017 Dec;42(12):941-944

From the Department of Radiology, University of Southern California, Los Angeles, CA.

An institutional review board-approved retrospective review of 55 patients who received cardiac MRI within 1 year of myocardial SPECT was performed. Forty-nine demonstrated myocardial infarction by MRI. MRI and SPECT agreed in all but 1 case, where SPECT preceded MRI by 97 days. Three cases are presented here: 2 demonstrating congruent MRI and SPECT changes in a vascular distribution status post infarction and a third with a nonvascular pattern of abnormalities related to left ventricular aneurysm in cardiac sarcoidosis. It is useful to review and correlate myocardial SPECT with available cardiac MRI, especially in patients with matching perfusion defects.
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http://dx.doi.org/10.1097/RLU.0000000000001851DOI Listing
December 2017

Doppler US in the Evaluation of Fetal Growth and Perinatal Health.

Radiographics 2017 Oct;37(6):1831-1838

From the Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine (K.R.U., B.H.G., R.H.C.), and Department of Radiology (A.E.P., E.G.G., D.K.W.), Keck School of Medicine, University of Southern California, 2020 Zonal Ave, IRD 203, Los Angeles, CA 90033.

Fetal growth restriction is commonly defined as an estimated fetal weight (EFW) that is below the 10th percentile for gestational age. It is associated with an increased risk of intrauterine demise, neonatal morbidity, and neonatal death; therefore, antenatal detection and surveillance with the optimization of delivery timing are necessary to improve pregnancy outcomes. If the estimated due date has been verified and the EFW is below the 10th percentile for gestational age, the underlying cause should be investigated, since the clinical management, outcome, and counseling options are largely dependent on the cause of the growth restriction. Serial ultrasonography (US) for the evaluation of fetal growth and umbilical artery Doppler velocimetry are used to guide pregnancy management decisions. This article describes the accurate US detection and surveillance of fetal growth restriction, discusses the current obstetric and radiology literature regarding the use of Doppler velocimetry in the setting of fetal growth restriction, and describes the techniques for performing umbilical artery Doppler velocimetry. Although various Doppler techniques have been described in the setting of fetal growth restriction, only umbilical artery Doppler assessment is recommended to identify fetuses most at risk for poor outcome and to guide the timing of delivery. The use of other Doppler waveforms in this setting remains investigational. RSNA, 2017.
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http://dx.doi.org/10.1148/rg.2017170020DOI Listing
October 2017

A 63-Year-Old Woman With Neurofibromatosis Type 1 and Pulmonary Hypertension With Worsening Hypoxemia.

Chest 2017 10;152(4):e89-e93

Division of Pulmonary, Critical Care, and Sleep Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA.

Case Presentation: A 63-year-old woman with a history of neurofibromatosis type-1 (NF-1) and pulmonary arterial hypertension (PAH) thought to be secondary to the NF-1 presented with a few weeks of worsening dyspnea on exertion. She took no medications other than sildenafil for her pulmonary hypertension (PH). She denied tobacco, alcohol, and illicit or anorectic drug use. She had previously worked as a waitress. Her mother and her brother had NF-1 but no PH or lung disease.
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http://dx.doi.org/10.1016/j.chest.2017.05.014DOI Listing
October 2017

Delayed Development of Multiple Pancreaticoduodenal Arcade Pseudoaneurysms after Abdominal Trauma.

Ann Vasc Surg 2016 Oct 15;36:297.e11-297.e15. Epub 2016 Jul 15.

Department of Radiology, University of Southern California, Los Angeles, CA. Electronic address:

This case report demonstrates development and progressive enlargement of multiple pancreaticoduodenal arcade pseudoaneurysms using computed tomography angiographies over a period of 5 weeks after abdominal trauma. The mechanism of pseudoaneurysm formation, as shown by serial imaging, attributed to preexisting celiac axis stenosis by the median arcuate ligament, posttraumatic celiac artery dissection, and secondary occlusion of proper hepatic artery resulting in elevation of pressure and flow in the pancreaticoduodenal arcade and rupture of small arterial branches. Successful pseudoaneurysm occlusion was achieved through arterial embolization.
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http://dx.doi.org/10.1016/j.avsg.2016.04.011DOI Listing
October 2016

Spine infections.

Neuroimaging Clin N Am 2012 Nov 2;22(4):755-72. Epub 2012 Oct 2.

Division of Neuroradiology, Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.

Infections of the spine represent a rare but potentially debilitating and neurologically devastating condition for patients. Early diagnosis, imaging, and intervention may prevent some of the more critical complications that may ensue from this disease process, including alignment abnormalities, central canal compromise, nerve root impingement, vascular complications, and spinal cord injury. This article reviews the underlying pathophysiologic basis of infection, clinical manifestations, and imaging modalities used to diagnose infections of the spine and spinal cord.
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http://dx.doi.org/10.1016/j.nic.2012.06.002DOI Listing
November 2012
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