Daniel Ennis Ph.D

ennis

Associate Professor
Department of Radiological Sciences
Department of Bioengineering

Peter V. Ueberroth Bldg., Suite 1417B
310-206-0713

 

Education

  • BS, University of California, San Diego, 1997
  • PhD, John Hopkins University, 2004
  • Post-doctoral fellow, Stanford University, 2004-2006
  • Research Fellow, Stanford University, 2006-2008

 

 Positions

  • Visiting Scientist, University of Auckland, Bioengineering Institute, Auckland MRI Research Group, 2008 (Winter)

Research Interests

Professor Ennis is interested in both the basic science and clinical applications of MRI for evaluating cardiovascular structure, function, and remodeling. Work in his laboratory uses a principled combination of theory, simulation, and experimental work to bring improvements to the imaging speed and accuracy of cardiovascular MRI exams.  In particular, his group is currently focused on developing advanced methods for pediatric cardiovascular exams that may improve patient acceptance, while maintaining or improving diagnostic image quality.  His group is also focused on developing quantitative imaging methods that can provide insight to changes in cardiovascular structure and function during the progression of disease or in response to pharmacologic therapy.

Scientists in his group also work to better understand the risks associated with MRI scanning of patients with implanted devices and technical approaches to mitigating these risks by modifying the MRI exam.

Researchers in the Ennis Lab are also developing methods that provide insight to myocardial microstructural remodeling in disease by evaluating changes microstructural organization that can be measured with DT-MRI and evaluated with tensor-field image processing methods.  These same studies lend themselves to the building of computational models of cardiac electrophysiology, which can be used to better understand electrical abnormalities of the heart.

Links

Published Manuscripts @Pubmed or @Google Scholar

Recent Papers

1.   Zhou W, Yamakawa K, Benharash P, Ajijola OA, Ennis DB, Hadaya J, Vaseghi M, Shivkumar K, Mahajan A. Effect of Stellate Ganglia Stimulation on Global and Regional Left Ventricular Function Assessed by Speckle Tracking Echocardiography. Am J Physiol Heart Circ Physiol 2013 [PMID 23335795].

2.   Reyhan M, Ennis DB. Quantitative assessment of systolic and diastolic left ventricular twist using Fourier Analysis of Stimulated echoes (FAST) and CSPAMM. J Magn Reson Imaging 2013;37(3):678-683 [PMID 23371791].

3.   Middione MJ, Ennis DB. Chemical shift-induced phase errors in phase-contrast MRI [ISMRM Young Investigator Award Winner]. Magn Reson Med 2013;69(2):391-401 [PMID 22488490].

4.   Zhan L, Jahanshad N, Ennis DB, Jin Y, Bernstein MA, Borowski BJ, Jack CR, Jr., Toga AW, Leow AD, Thompson PM. Angular versus spatial resolution trade-offs for diffusion imaging under time constraints. Hum Brain Mapp 2012 [PMID 22522814].

5.   Wang VY, Ennis DB, Cowan BR, Young AA, Nash MP. Myocardial contractility and regional work throughout the cardiac cycle using FEM and MRI. Proceedings of the Second international conference on Statistical Atlases and Computational Models of the Heart: imaging and modelling challenges. Toronto, ON, Canada: Springer-Verlag;
2012. p 149-159.

6.   Reyhan M, Natsuaki Y, Ennis DB. Fourier analysis of STimulated echoes (FAST) for the quantitative analysis of left ventricular twist. J Magn Reson Imaging 2012;35(3):587-593 [PMID 22069227].

7.   Moriarty JM, Kung GL, Ramos Y, Moghaddam AN, Ennis DB, Finn JP. Injection of gadolinium contrast through pediatric central venous catheters: a safety study. Pediatr Radiol 2012;42(9):1064-1069 [PMID 22526282].

8.   Langman DA, Goldberg IB, Judy J, Paul Finn J, Ennis DB. The dependence of radiofrequency induced pacemaker lead tip heating on the electrical conductivity of the medium at the lead tip. Magn Reson Med 2012;68(2):606-613 [PMID 22213610].

9.   Langman D, Finn JP, Ennis D. Letters to the Editor. Pacing Clin Electrophysiol 2012 [PMID 22229942].

10. Itoh A, Stephens EH, Ennis DB, Carlhall CJ, Bothe W, Nguyen TC, Swanson JC, Miller DC, Ingels NB, Jr. Contribution of myocardium overlying the anterolateral papillary muscle to left ventricular deformation. Am J Physiol Heart Circ Physiol 2012;302(1):H180-187 [PMID 22037187].

11. Gahm JK, Wisniewski N, Kindlmann G, Kung GL, Klug WS, Garfinkel A, Ennis DB. Linear invariant tensor interpolation applied to cardiac diffusion tensor MRI. Med Image Comput Comput Assist Interv 2012;15(Pt 2):494-501 [PMID 23286085].

12. Reyhan M, Natsuaki Y, Ennis DB. Fourier analysis of STimulated echoes (FAST) for the quantitative analysis of left ventricular twist. J Magn Reson Imaging 2011 [PMID 22069227].

13. Langman DA, Goldberg IB, Finn JP, Ennis DB. Pacemaker lead tip heating in abandoned and pacemaker-attached leads at 1.5 Tesla MRI. J Magn Reson Imaging 2011;33(2):426-431 [PMID 21274985].

14. Langman DA, Finn JP, Ennis DB. Abandoned Pacemaker Leads Are a Potential Risk for Patients Undergoing RI. Pacing Clin Electrophysiol 2011 [PMID 21797902].

15. Kung GL, Nguyen TC, Itoh A, Skare S, Ingels NB, Jr., Miller DC, Ennis DB. The presence of two local yocardial sheet populations confirmed by diffusion tensor MRI and histological validation. J Magn Reson Imaging 2011;34(5):1080-1091 [PMID 21932362].

16. Thompson RB, Paterson I, Chow K, Cheng-Baron J, Scott JM, Esch BT, Ennis DB, Haykowsky MJ. Characterization of the relationship between systolic shear strain and early diastolic shear strain rates: insights into torsional recoil. Am J Physiol Heart Circ Physiol 2010;299(3):H898-907 [PMID 20562339].

17. Nasiraei Moghaddam A, Saber NR, Wen H, Finn JP, Ennis DB, Gharib M. Analytical method to measure three-dimensional strain patterns in the left ventricle from single slice displacement data. J Cardiovasc Magn Reson 2010;12(1):33 [PMID
20515489].

18. Ennis DB, Rudd-Barnard GR, Li B, Fonseca CG, Young AA, Cowan BR, Stewart RA. Changes in mitral annular geometry and dynamics with ß-blockade in patients with degenerative mitral valve disease. Circ Cardiovasc Imaging 2010;3(6):687-693 [PMID 20847190].

 

Recent Publications

  1. Wang Z, Nasiraei-Moghaddam A, Reyhan ML, Srinivasan S, Finn JP, Ennis DB. Complementary radial tagging for improved myocardial tagging contrast. Magn Reson Med 2015;73(4):1432-1440 [10.1002/mrm.25259].
  2. Wang D, Shao J, Rapacchi S, Middione MJ, Ennis DB, Hu P. Phase contrast MRI with flow compensation view sharing. Magn Reson Med 2015;73(2):505-513 [10.1002/mrm.25133].
  3. Srinivasan S, Ennis DB. Optimal flip angle for high contrast balanced SSFP cardiac cine imaging. Magn Reson Med 2015;73(3):1095-1103 [10.1002/mrm.25228].
  4. Perotti LE, Krishnamoorthi S, Borgstrom NP, Ennis DB, Klug WS. Regional segmentation of ventricular models to achieve repolarization dispersion in cardiac electrophysiology modeling. International journal for numerical methods in biomedical engineering 2015 [10.1002/cnm.2718].
  5. White BM, Santhanam A, Thomas D, Min Y, Lamb JM, Neylon J, Jani S, Gaudio S, Srinivasan S, Ennis D, Low DA. Modeling and incorporating cardiac-induced lung tissue motion in a breathing motion model. Med Phys 2014;41(4):043501 [10.1118/1.4866888].
  6. Wang D, Shao J, Rapacchi S, Middione MJ, Ennis DB, Hu P. Phase contrast MRI with flow compensation  view sharing. Magn Reson Med 2014 [10.1002/mrm.25133].
  7. Stevens SM, Tung R, Rashid S, Gima J, Cote S, Pavez G, Khan S, Ennis DB, Finn JP, Boyle N, Shivkumar K, Hu P. Device artifact reduction for magnetic resonance imaging of patients with implantable cardioverter-defibrillators and ventricular tachycardia: Late gadolinium enhancement correlation with electroanatomic mapping. Heart Rhythm 2014;11(2):289-298 [Doi 10.1016/J.Hrthm.2013.10.032].
  8. Srinivasan S, Wu HH, Sung K, Margolis DJ, Ennis DB. Fast 3D T -weighted imaging using variable flip angle transition into driven equilibrium (3D T -TIDE) balanced SSFP for prostate imaging at 3T. Magn Reson Med 2014 [10.1002/mrm.25430].
  9. Srinivasan S, Ennis DB. Optimal flip angle for high contrast balanced SSFP cardiac cine imaging. Magn Reson Med 2014 [10.1002/mrm.25228].
  10. Song HK, Yan L, Smith RX, Xue Y, Rapacchi S, Srinivasan S, Ennis DB, Hu P, Pouratian N, Wang DJ.Noncontrast enhanced four-dimensional dynamic MRA with golden angle radial acquisition and K-space weighted image contrast (KWIC) reconstruction. Magn Reson Med 2014;72(6):1541-1551 [10.1002/mrm.25057].
  11. Sarma M, Hu P, Rapacchi S, Ennis D, Thomas A, Lee P, Kupelian P, Sheng K. Accelerating dynamic magnetic resonance imaging (MRI) for lung tumor tracking based on low-rank decomposition in the spatial-temporal domain: a feasibility study based on simulation and preliminary prospective undersampled MRI. Int J Radiat Oncol Biol Phys 2014;88(3):723-731 [10.1016/j.ijrobp.2013.11.217].
  12. Santhanam A, Benharash P, Frank P, White B, Min Y, Ennis D, Kupelian P, Dutson E. A framework for modeling and visualizing cardiovascular deformation under normal and altered circulatory conditions. Stud Health Technol Inform 2014;196:378-383].
  13. Reyhan M, Wang Z, Li M, Kim HJ, Gupta H, Lloyd SG, Dell’Italia LJ, Denney T, Ennis DB. Left ventricular twist and shear in patients with primary mitral regurgitation. J Magn Reson Imaging 2014 [10.1002/jmri.24811].
  14. Reyhan M, Natsuaki Y, Ennis DB. Off-resonance insensitive complementary SPAtial Modulation of Magnetization (ORI-CSPAMM) for quantification of left ventricular twist. J Magn Reson Imaging 2014;39(2):339-345 [10.1002/jmri.24154].
  15. Reyhan M, Kim HJ, Brown MS, Ennis DB. Intra- and interscan reproducibility using Fourier Analysis of STimulated Echoes (FAST) for the rapid and robust quantification of left ventricular twist. J Magn Reson Imaging 2014;39(2):463-468 [10.1002/jmri.24162].
  16. Middione MJ, Wu HH, Ennis DB. Convex gradient optimization for increased spatiotemporal resolution and improved accuracy in phase contrast MRI. Magn Reson Med 2014;72(6):1552-1564 [10.1002/mrm.25059].
  17. Middione MJ, Thompson RB, Ennis DB. Velocity encoding with the slice select refocusing gradient for faster imaging and reduced chemical shift-induced phase errors. Magn Reson Med 2014;71(6):2014-2023 [10.1002/mrm.24861].
  18. Krishnamoorthi S, Perotti LE, Borgstrom NP, Ajijola OA, Frid A, Ponnaluri AV, Weiss JN, Qu Z, Klug WS, Ennis DB, Garfinkel A. Simulation Methods and Validation Criteria for Modeling Cardiac Ventricular Electrophysiology. PLoS One 2014;9(12):e114494 [10.1371/journal.pone.0114494 PONE-D-14-29104].
  19. Krishnamoorthi S, Perotti LE, Borgstrom NP, Ajijola OA, Frid A, Ponnaluri AV, Weiss JN, Qu Z, Klug WS, Ennis DB, Garfinkel A. Simulation Methods and Validation Criteria for Modeling Cardiac Ventricular Electrophysiology. PLoS One 2014;9(12):e114494 [10.1371/journal.pone.0114494 PONE-D-14-29104].
  20. Gahm JK, Kindlmann G, Ennis DB. The effects of noise over the complete space of diffusion tensor shape. Med Image Anal 2014;18(1):197-210 [10.1016/j.media.2013.10.009 S1361-8415(13)00153-9].
  21. Gahm JK, Ennis DB. Dyadic Tensor-Based Interpolation of Tensor Orientation: Application to Cardiac DT-MRI. Statistical Atlases and Computational Models of the Heart Imaging and Modelling Challenges 2014;8330(16):135-142 [10.1007/978-3-642-54268-8_16].
  22. Axel L, Wedeen VJ, Ennis DB. Probing dynamic myocardial microstructure with cardiac magnetic resonance diffusion tensor imaging. J Cardiovasc Magn Reson 2014;16:89 [10.1186/s12968-014-0089-6 s12968-014-0089-6].