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Rizwan Ahmad

  • Assistant Professor, Electrical & Computer Engr.
  • Assistant Professor, Biomedical Engineering
  • 1080 Carmack Rd
    Columbus, OH 43210

About

Education

PhD: Ohio State University, Department of Electrical and Computer Engineering, 2007

MS: Electrical and Computer Engineering, The Ohio State University, March 2004

BS: (with honors) in Electrical Engineering, University of Engineering & Tech., Lahore, Pakistan, December 2000

Areas of Interest

Ahmad's research aims to bring engineering innovations to biomedical imaging. He is particularly interested in developing data acquisition and image reconstruction methods that improve diagnostic accuracy of established or emerging imaging modalities. His research expertise encompasses digital signal and image processing, tomographic reconstruction, linear and nonlinear inverse problems, statistical sensitivity analysis, multimodal imaging, and biomedical instrumentation, with application to magnetic resonance imaging (MRI) and electron paramagnetic resonance (EPR) spectroscopy and imaging.

Office

126A Tzagournis Medical Research Facility, 420 W 12th Avenue, Columbus OH, 43210

 

Honors

  • October, 2018

    Second-position for Chen Chong (post-doc) in DHLRI Research Day.

  • April, 2017

    Power pitch (awarded to top 2.7% abstracts).

  • April, 2017

    Lumley Research Award.

  • February, 2016

    Power pitch (awarded to top 2.7% abstracts).

  • June, 2015

    Show and Tell (top 10% of the conference papers).

  • May, 2015

    Distinguished reviewer.

  • February, 2015

    Power pitch (awarded to top 2.7% abstracts).

  • May, 2014

    Distinguished reviewer.

  • October, 2012

    Poster competition at annual research retreat (1st place).

  • April, 2011

    Lumley Interdisciplinary Research Award.

  • October, 2009

    Poster competition at annual research retreat (2nd place).

  • April, 2005

    Young researcher award.

  • December, 2000

    Top-ten student in the department.

Chapters

2017

  • 2017. "Recovering Signals with Unknown Sparsity in Multiple Dictionaries." In Compressed Sensing and its Applications. Applied and Numerical Harmonic Analysis, edited by Boche, H.; Caire, G.; Calderbank, R.; März, M.; Kutyniok, G.; Mathar, R.,

2011

  • Ahmad, R.; Kuppusmay, P.. 2011. "EPR Imaging: Theory and Instrumentation." edited by Misra, S.K.,

2010

  • Ahmad, R.; Khan, M.; Vikram, D.S.; Bratasz, A. et al.. 2010. "EPR Oximetry: Method and Application." edited by Das, D.K.,

Journal Articles

2019

  • Rich, A.; Potter, L.C.; Jin, N.; Liu, Y. et al., 2019, "A Bayesian approach for 4D flow imaging of aortic valve in a single breath-hold.." Magnetic resonance in medicine 81, no. 2, 811-824 - 811-824.

2013

  • Golub, F.; Potter, L.C.; Ash, J.N.; Blank, A. et al., 2013, "Estimation of spin-echo relaxation time.." Journal of magnetic resonance (San Diego, Calif. : 1997) 237, 17-22 - 17-22.

2012

  • Ahmad, R.; Som, S.; Johnson, D.H.; Zweier, J.L. et al., 2012, "Multisite EPR oximetry from multiple quadrature harmonics.." Journal of magnetic resonance (San Diego, Calif. : 1997) 214, no. 1, 135-143 - 135-143.
  • Palmer, J.; Potter, L.C.; Johnson, D.H.; Zweier, J.L. et al., 2012, "Dual-scan acquisition for accelerated continuous-wave EPR oximetry.." Journal of magnetic resonance (San Diego, Calif. : 1997) 222, 53-58 - 53-58.
  • Ahmad, R.; Potter, L.C.; Khramtsov, V.V., 2012, "Spectral modeling for accelerated pH spectroscopy using EPR.." Journal of magnetic resonance (San Diego, Calif. : 1997) 218, 86-92 - 86-92.

2011

  • Palmer, J.; Potter, L.C.; Ahmad, R., 2011, "Optimization of magnetic field sweep and field modulation amplitude for continuous-wave EPR oximetry.." Journal of magnetic resonance (San Diego, Calif. : 1997) 209, no. 2, 337-340 - 337-340.

2010

  • Ahmad, R.; Som, S.; Kesselring, E.; Kuppusamy, P. et al., 2010, "Digital detection and processing of multiple quadrature harmonics for EPR spectroscopy.." Journal of magnetic resonance (San Diego, Calif. : 1997) 207, no. 2, 322-331 - 322-331.

2008

  • Vikram, D.S.; Ahmad, R.; Rivera, B.K.; Kuppusamy, P., 2008, "Mapping of oxygen concentration in biological samples using EPR imaging." Israel Journal of Chemistry 48, no. 1,
  • Ahmad, R.; Vikram, D.S.; Potter, L.C.; Kuppusamy, P., 2008, "Estimation of mean and median pO2 values for a composite EPR spectrum.." Journal of magnetic resonance (San Diego, Calif. : 1997) 192, no. 2, 269-274 - 269-274.
  • Som, S.; Potter, L.C.; Ahmad, R.; Vikram, D.S. et al., 2008, "EPR oximetry in three spatial dimensions using sparse spin distribution.." Journal of magnetic resonance (San Diego, Calif. : 1997) 193, no. 2, 210-217 - 210-217.

2007

  • Ahmad, R.; Vikram, D.S.; Clymer, B.; Potter, L.C. et al., 2007, "Uniform distribution of projection data for improved reconstruction quality of 4D EPR imaging.." Journal of magnetic resonance (San Diego, Calif. : 1997) 187, no. 2, 277-287 - 277-287.
  • Som, S.; Potter, L.C.; Ahmad, R.; Kuppusamy, P., 2007, "A parametric approach to spectral-spatial EPR imaging.." Journal of magnetic resonance (San Diego, Calif. : 1997) 186, no. 1, 1-10 - 1-10.
  • Ahmad, R.; Clymer, B.; Vikram, D.S.; Deng, Y. et al., 2007, "Enhanced resolution for EPR imaging by two-step deblurring.." Journal of magnetic resonance (San Diego, Calif. : 1997) 184, no. 2, 246-257 - 246-257.
  • Ahmad, R.; Deng, Y.; Vikram, D.S.; Clymer, B. et al., 2007, "Quasi Monte Carlo-based isotropic distribution of gradient directions for improved reconstruction quality of 3D EPR imaging.." Journal of magnetic resonance (San Diego, Calif. : 1997) 184, no. 2, 236-245 - 236-245.

2006

  • Ahmad, R.; Vikram, D.S.; Petryakov, S.; Deng, Y. et al., 2006, "Automated on-the-fly detection and correction procedure for EPR imaging data acquisition.." Magnetic resonance in medicine 56, no. 3, 644-653 - 644-653.
  • Deng, Y.; Pandian, R.P.; Ahmad, R.; Kuppusamy, P. et al., 2006, "Application of magnetic field over-modulation for improved EPR linewidth measurements using probes with Lorentzian lineshape.." Journal of magnetic resonance (San Diego, Calif. : 1997) 181, no. 2, 254-261 - 254-261.
  • Ahmad, R.; Clymer, B.; Deng, Y.; He, G. et al., 2006, "Optimization of data acquisition for EPR imaging.." Journal of magnetic resonance (San Diego, Calif. : 1997) 179, no. 2, 263-272 - 263-272.

Presentations

  • "Accelerated Cardiac MRI." 2016, Presented at Meeting with GE MRI Research Team,

Papers in Proceedings

2018

  • Rich, A.; Ahmad, R. "MR Image Reconstruction via Denoising (MR-RED)." (1 2018).
  • Simonetti, O.; Ahmad, R. "The Potential for Cardiovascular MRI at Low Field." (1 2018).
  • Zhao, S.; Potter, L.; Jin, N.; Liu, Y. et al. "PC-MRI with Phase Recovery from Multiple Wrapped Measurements (PRoM)." (1 2018).
  • Varghese, J.; Ahmad, R.; Raman, S.; Potter, L. et al. "Non-invasive quantitative estimation of blood oxygen saturation with MRI: feasibility of machine learning." (1 2018).
  • Varghese, J.; Desai, L.; Ahmad, R.; Potter, L.C. et al. "Non-invasive MR-based blood oximetry via multi-parametric, non-linear estimation: initial multi-center experience in adult and pediatric patients." (1 2018).
  • Dong, H.; Ahmad, R.; Kolipaka, A. "Helmholtz Inversion Using Unconstrained Optimization for MR Elastography." (1 2018).
  • Rich, A.; Jin, N.; Liu, Y.; Potter, L. et al. "CArtesian sampling with Variable density and Adjustable temporal resolution (CAVA)." (1 2018).
  • Pruitt, A.; Jin, N.; Liu, Y.; Simonetti, O. et al. "Background phase correction in the presence wrap-around artifact: Application in 4D flow imaging." (1 2018).
  • Rich, A.; Liu, Y.; Jin, N.; Potter, L. et al. "Single Breath Hold 4D Flow Acquisition of the Aortic Valve." (1 2018).
  • Chen, C.; Liu, Y.; Simonetti, O.; Ahmad, R. "Reconstructing real-time exercise stress cine images with multiple sets of sensitivity maps." (1 2018).
  • Varghese, J.; Liu, Y.; Jin, N.; Armstrong, A. et al. "Comparison of Intra-Cardiac Magnetic Resonance Blood Oximetry to Invasive Catheterization in Pediatric Patients with Congenital Heart Disease." (1 2018).
  • Liu, Y.; Ahmad, R.; Jin, N.; Tani, D. et al. "Strain Encoding (SENC) Using EPI Readout." (1 2018).
  • Bush, M.; Simonetti, O.; Ahmad, R.; Liu, Y. et al. "Patient specific prospective respiratory motion correction for efficient, free-breathing cardiovascular MRI." (1 2018).
  • Bush, M.A.; Simonetti, O.; Ahmad, R.; Liu, Y. et al. "Prospective correction of patient-specific respiratory motion in T1 mapping." (1 2018).
  • Varghese, J.; Cardona, A.; Raman, S.; Ahmad, R. et al. "Comparison of Cardiac Magnetic Resonance-Derived Blood Oximetry to Invasive Catheterization in Heart Transplant Recipients." (1 2018).
  • Pruitt, A.; Liu, Y.; Jin, N.; Simonetti, O. et al. "Automatic Image-Based Background Phase Correction in the Presence of Wrap-Around Artifact." (1 2018).
  • Bush, M.; Ahmad, R.; Liu, Y.; Jin, N. et al. "Prospective correction of patient-specific respiratory motion in T1 and T2 mapping." (1 2018).

2017

  • Rich, A.V.; Potter, L.C.; Jin, N.; Liu, Y. et al. "A Bayesian Approach to Enable Single Breath-hold 4D Flow MRI." (1 2017).
  • Liu, Y.; Ting, S.; Jin, N.; Simonetti, O.P. et al. "Fully Automated Online Compressive Recovery for Real-Time, Free-Breathing CINE." (1 2017).
  • Varghese, J.; Ahmad, R.; Raman, S.; Potter, L.C. et al. "Intracardiac MR Oximetry in Patients with Cardiovascular Disease: Preliminary Comparison with Right Heart Catheterization." (1 2017).
  • Pruitt, A.; Jin, N.; Simonetti, O.; Liu, Y. et al. "An Outlier Rejection Scheme to Improve Background Phase Correction in PC-MRI." (1 2017).
  • Ebersole, C.; Ahmad, R.; Rich, A.; Potter, L. et al. "Highly Accelerated Magnetic Resonance Elastography Via Bayesian Modeling." (1 2017).
  • Dong, H.; Joseph, M.; Kalra, P.; Mo, X. et al. "In Vivo Magnetic Resonance Elastography of Abdominal Aortic Aneurysm in a Porcine Model." (1 2017).
  • Bush, M.; Ahmad, R.; Simonetti, O.P. "Respiratory motion compensation for efficient, free-breathing cardiovascular MRI." (1 2017).

2016

  • Varghese, J.; Ahmad, R.; Jin, N.; Potter, L.C. et al. "Venous oxygen saturation estimation from multiple T2 maps with varying inter-echo spacing." (1 2016).
  • da Silveira, J.; Rich, A.V.; Liu, Y.; Smyke, M. et al. "Highly accelerated phase-contrast MRI-based multi-directional flow imaging for peak velocity estimation in aortic stenosis patients.." (1 2016).
  • Adam, R.; Potter, L.C.; Jin, N.; Silveira, J.S.D. et al. "Joint processing of highly accelerated multi-directional phase-contrast MRI using ReVEAL." (1 2016).
  • da Silveira, J.; Smyke, M.E.; Ahmad, R.; Jin, N. et al. "Peak velocity estimation in aortic stenosis patients using a fast three-directional two-dimensional phase contrast technique in a single breath-hold: comparison to unidirectional phase contrast MRI and transthoracic echocardiography." (1 2016).
  • Ting, S.T.; Ahmad, R.; Jin, N.; Simonetti, O.P. "Patch-based, iteratively-reweighted compressive recovery for reconstruction of highly accelerated exercise stress cardiac cine." (1 2016).
  • Ahmad, R.; Schroede, S.A.; White, R.D.; Kolipaka, A. "Accelerated MR Elastography for Quantitative Measurement of Myocardial Stiffness." (1 2016).
  • Varghese, J, Ahmad, R, Jin, N, Potter, LC, Simonetti, OP "Venous Oxygen Saturation Estimation from Multiple T2 Maps with Varying Inter-Echo Spacing." in Annual SCMR Workshop: Quantitative CMR: From Technique Development to Practical Implementation. (1 2016).
  • Serafim da Silveira, J, Smyke, ME, Ahmad, R, Jin, N, Scandling, D, Dickerson, JA, Rochitte, CE, Raman, SV, Simonetti, OP "Peak velocity estimation in aortic stenosis patients using a fast three-directional two-dimensional phase contrast technique in a single breath-hold: comparison to unidirectional phase contrast MRI and transthoracic echocardiography." in SCMR 19th Annual Scientific Sessions. (1 2016).
  • Ahmad, R.; Jin, N.; Simonetti, O.P. "Background Phase Correction for Quantitative Phase-Contrast MRI." (1 2016).
  • Serafim da Silveira, J, Rich, A, Liu, Y, Smyke, M, Jin, N, Scandling, D, Dickerson, JA, Rochitte, CE, Raman, S, Potter, LC, Ahmad, R, Simonetti, OP "Highly Accelerated Phase-Contrast Mri-Based Multi-Directional Flow Imaging for Peak Velocity Estimation in Aortic Stenosis Patients." in Annual SCMR Workshop: Quantitative CMR: From Technique Development to Practical Implementation. (1 2016).
  • Ahmad R, Schroeder SA, White RD, Kolipaka A. "Accelerated MR Elastography for Quantitative Measurement of Myocardial Stiffness.." in ISMRM. (5 2016).

2015

  • Rich, A.; Potter, L.C.; Ash, J.N.; Ahmad, R. et al. "FACTOR GRAPHS FOR INVERSE PROBLEMS: ACCELERATED PHASE CONTRAST MAGNETIC RESONANCE IMAGING." (1 2015).
  • Wolfson, H.; Ahmad, R.; Twig, Y.; Blank, A. et al. "A hand-held EPR scanner for transcutaneous oximetry." (1 2015).
  • Ting, S.T.; Ahmad, R.; Jin, N.; Serafim da Silveira, J. et al. "Low Latency Reconstruction of Free-breathing Real-time Cardiac Cine with VISTA and SENSE." (1 2015).
  • Ahmad, R.; Schniter, P.; Simonetti, O.P. "Parameter-Free Sparsity Adaptive Compressive Recovery (SCoRe)." (1 2015).
  • Rich, A.; Potter, L.C.; Jin, N.; Ash, J. et al. "A Bayesian Approach for Accelerated Phase Contrast MRI." (1 2015).
  • Rich, A.; Potter, L.C.; Ashi, J.N.; Ahmad, R. "Factor graphs for inverse problems: Accelerated phase contrast magnetic resonance imaging." (9 2015).
  • Rich, A, Potter, LC, Ash, J, Ahmad, R "Factor Graphs for Inverse Problems: Accelerated Phase Contrast Magnetic Resonance Imaging." in 2015 IEEE International Conference on Image Processing (ICIP). (1 2015).
  • Ting, ST, Ahmad, R, Jin, N, Serafim da Silveira, J, Simonetti, OP "Low Latency Reconstruction of Free-breathing Real-time Cardiac Cine with VISTA and SENSE." in ISMRM 23rd Annual Meeting & Exhibition. (1 2015).
  • Rich, A, Potter, LC, Jin, N, Ash, J, Simonetti, OP, Ahmad, R "A Bayesian Approach for Accelerated Phase Contrast MRI." in ISMRM 23rd Annual Meeting & Exhibition. (1 2015).
  • Rich, A.; Potter, L.C.; Ash, J.N.; Ahmad, R. "FACTOR GRAPHS FOR INVERSE PROBLEMS: ACCELERATED PHASE CONTRAST MAGNETIC RESONANCE IMAGING." in IEEE International Conference on Image Processing (ICIP). (1 2015).
  • Ahmad, R, Schniter, P, Simonetti, OP "Parameter-Free Sparsity Adaptive Compressive Recovery (SCoRe)." in ISMRM 23rd Annual Meeting & Exhibition. (1 2015).
  • Rich, A.; Potter, L.C.; Ashi, J.N.; Ahmad, R. "Factor graphs for inverse problems: Accelerated phase contrast magnetic resonance imaging." (12 2015).

2014

  • Ding, Y, Ahmad, R, Jin, N, Simonetti, OP "A New Perspective on the 4-point Balanced Velocity-encoding." in ISMRM 22nd Annual Meeting & Exhibition. (1 2014).
  • Ahmad, R.; Jin, N.; Ding, Y.; Simonetti, O. "An Adaptive Phase Recovery Method for 4D Phase-Contrast MRI." (1 2014).
  • Rich, A.; Potter, L.; Jin, N.; Ash, J. et al. "A Factor Graph Approach for Accelerated Phase Contrast MRI." (1 2014).
  • Ding, Y.; Ahmad, R.; Jin, N.; Simonetti, O. "A New Perspective on the 4-point Balanced Velocity-encoding." (1 2014).
  • Ting, S.; Ding, Y.; Xue, H.; Giri, S. et al. "Sub-30ms Real-Time, Free-Breathing Cardiac Cine with VISTA Sampling and SPIRiT Reconstruction: A Comparison with Conventional Segmented Cine." (1 2014).
  • Ahmad, R.; Ting, S.T.; Craft, J.; Giri, S. et al. "High-resolution, real-time exercise stress cine." (1 2014).
  • Ting, Samuel, Ding, Yu, Xue, Hui, Giri, Shivraman, Jin, Ning, Ahmad, Rizwan, Simonetti, Orlando P "Sub-30ms Real-Time, Free-Breathing Cardiac Cine with VISTA Sampling and SPIRiT Reconstruction: A Comparison with Conventional Segmented Cine." in ISMRM 22nd Annual Meeting & Exhibition. (1 2014).
  • Ahmad, R, Jin, N, Ding, Y, Simonetti, OP "An Adaptive Phase Recovery Method for 4D Phase-Contrast MRI." in ISMRM 22nd Annual Meeting & Exhibition. (1 2014).
  • Ting, S.T.; Ding, Y.; Giri, S.; Jin, N. et al. "Sub-30 ms real-time, free-breathing cardiac imaging with SPIRiT." (1 2014).
  • Ting, ST, Ding, Y, Giri, S, Jin, N, Simonetti, OP, Ahmad, R Sub-30 ms real-time, free-breathing cardiac imaging with SPIRiT. http://www.jcmr-online.com/content/16/S1/W2, (1 2014).
  • Ahmad, R, Ting, ST, Craft, J, Giri, S, Jin, N, Raman, SV, Simonetti, OP High-resolution, real-time exercise stress cine. http://www.jcmr-online.com/content/16/S1/W14, (1 2014).

2013

  • Ahmad, R.; Xue, H.; Ding, Y.; Simonetti, O.P. "Variable Density Incoherent Spatial-Temporal Acquisition (VISTA) for Cardiac MRI." (1 2013).
  • Ding, Y, Ahmad, R, Xue, H, Potter, LC, Ting, S, Jin, N, Simonetti, OP "A Bilinear Noise Transfer Model for SENSE Reconstruction." in ISMRM 21st Annual Meeting & Exhibition. (1 2013).
  • Johnson, DH, Chen, Z, Ahmad, R, Samouilov, A, Zweier, JL "Uniform Spinning Sampling Gradient Electron Paramagnetic Resonance Imaging." in ISMRM 21st Annual Meeting & Exhibition. (1 2013).
  • Ting, ST, Ding, Y, Ahmad, R, Xue, H, Simonetti, OP "Taming an Ill-Conditioned SPIRiT: Improved Iterative Image Reconstruction for Real-Time Cardiac MRI." in ISMRM 21st Annual Meeting & Exhibition. (1 2013).
  • Golub, F.; Potter, L.C.; Ash, J.N.; Ahmad, R. "T2 Estimation for Spin-Echo EPR." (1 2013).
  • Ahmad, R.; Jin, N.; Ding, Y.; Simonetti, O.P. "Direct Reconstruction (DiR) for PC-MRI." (1 2013).
  • Ting, S.T.; Ding, Y.; Ahmad, R.; Xue, H. et al. "Taming an Ill-Conditioned SPIRiT: Improved Iterative Image Reconstruction for Real-Time Cardiac MRI." (1 2013).
  • Ding, Y.; Ahmad, R.; Xue, H.; Ting, S.T. et al. "Comparing Boundary Sharpness of SENSE and GRAPPA." (1 2013).
  • Johnson, D.H.; Ahmad, R.; Samouilov, A.; Zweier, J.L. "Spatial 3D EPR Imaging with Compressed Sensing Reconstruction." (1 2013).
  • Ahmad, R.; Jin, N.; Ding, Y.; Simonetti, O.P. "A direct reconstruction method for blood velocity estimation from phase-contrast MRI data." (1 2013).
  • Ding, Y.; Xue, H.; Ahmad, R.; Ting, S.T. et al. "A Bilinear Noise Transfer Model for GRAPPA Reconstruction." (1 2013).
  • Ding, Y.; Ahmad, R.; Xue, H.; Potter, L.C. et al. "A Bilinear Noise Transfer Model for SENSE Reconstruction." (1 2013).
  • Ting, S.T.; Ahmad, R.; Ding, Y.; Xue, H. et al. "S-SPIRiT: An Iterative/Shrinkage Approach to SPIRiT for Real-Time Cardiac MRI." (1 2013).
  • Golub, F.; Potter, L.C.; Ahmad, R. "Characterization of EPR spin-echo data for accelerated oximetry." (1 2013).
  • Ding, Y.; Ahmad, R.; Xue, H.; Ting, S.T. et al. "L1-Regularized GRAPPA Kernel Estimate." (1 2013).
  • Palmer, J.; Potter, L.C.; Kuppusamy, P.; Ahmad, R. "Application-specific evaluation of oxygen measurement accuracy of EPR probes." (1 2013).
  • Johnson, D.H.; Chen, Z.; Ahmad, R.; Samouilov, A. et al. "Uniform Spinning Sampling Gradient Electron Paramagnetic Resonance Imaging." (1 2013).
  • Jin, N.; Ahmad, R.; Ding, Y.; Zuehlsdorff, S. et al. "High temporal-resolution three-directional velocity measurements in a single breath-hold using EPI and direct inversion." (1 2013).
  • Johnson, D.H.; Ahmad, R.; Samouilov, A.; Zweier, J.L. "Uniform Spinning Sampling Gradient Electron Paramagnetic Resonance Imaging." (1 2013).
  • Ahmad, R, Xue, H, Ding, Y, Simonetti, OP Variable Density Incoherent Spatial-Temporal Acquisition (VISTA) for Cardiac MRI. in ISMRM Workshop on Data Sampling and Image Reconstruction. http://www.ismrm.org/workshops/Data13/program.htm, (1 2013).
  • Golub, F, Potter, LC, Ahmad, R "Characterization of EPR spin-echo data for accelerated oximetry." in ISMRM 21st Annual Meeting & Exhibition. (1 2013).
  • Johnson, DH, Ahmad, R, Samouilov, A, Zweier, JL "Spatial 3D EPR Imaging with Compressed Sensing Reconstruction." in 41st Annual ISOTT/EPR 2013 Conference. (1 2013).
  • Golub, F, Potter, LC, Ash, JN, Ahmad, R T2 Estimation for Spin-Echo EPR. in 41st Annual ISOTT/EPR 2013 Conference. http://isott.org/index.php/news-reader/items/isott-2013-hanover-nh-usa.html, (1 2013).
  • Ding, Y, Xue, H, Ahmad, R, Ting, ST, Jin, N, Potter, LC, Simonetti, Orlando P "A Bilinear Noise Transfer Model for GRAPPA Reconstruction." in ISMRM Workshop on Data Sampling and Image Reconstruction. (1 2013).
  • Ting, Samuel T, Ahmad, Rizwan, Ding ,Yu, Xue, Hui, Potter, Lee C, Simonetti, Orlando P "S-SPIRiT: An Iterative/Shrinkage Approach to SPIRiT for Real-Time Cardiac MRI." in ISMRM 21st Annual Meeting & Exhibition. (1 2013).
  • Ding, Y, Ahmad, R, Xue, H, Ting, ST, Jin, N, Simonetti, OP "L1-Regularized GRAPPA Kernel Estimate." in ISMRM 21st Annual Meeting & Exhibition. (1 2013).
  • Jin, N, Ahmad, R, Ding, Y, Zuehlsdorff, S, Simonetti, OP "High temporal-resolution three-directional velocity measurements in a single breath-hold using EPI and direct inversion." in ISMRM 21st Annual Meeting & Exhibition. (1 2013).
  • Palmer, J, Potter, LC, Kuppusamy, P, Ahmad, R "Application-specific evaluation of oxygen measurement accuracy of EPR probes." in 41st Annual ISOTT/EPR 2013 Conference. (1 2013).
  • Johnson, DH, Ahmad, R, Samouilov, A, Zweier, JL "Uniform Spinning Sampling Gradient Electron Paramagnetic Resonance Imaging." in 41st Annual ISOTT/EPR 2013 Conference. (1 2013).
  • Ahmad, R, Jin, N, Ding, Y, Simonetti, OP "A direct reconstruction method for blood velocity estimation from phase-contrast MRI data." in ISMRM 21st Annual Meeting & Exhibition. (1 2013).
  • Ding, Y, Ahmad, R, Xue, H, Ting, ST, Jin, N, Simonetti, OP "Comparing Boundary Sharpness of SENSE and GRAPPA." in ISMRM Workshop on Data Sampling and Image Reconstruction. (1 2013).

2012

  • Ahmad, R.; Xue, H.; Ding, Y.; Simonetti, O.P. "Variable Density Incoherent Spatial-Temporal Acquisition for Cardiac MR." (1 2012).
  • Palaniappan, P, Simonetti, OP, Ding, Y, Ahmad, R, Xue, H, Chang, TC, Guetter, C "KLT and Wavelet Filtering: Reducing Noise in Highly Accelerated Dynamic Images." in ISMRM 20th Annual Meeting & Exhibition. (1 2012).
  • Palaniappan, P.; Simonetti, O.P.; Ding, Y.; Ahmad, R. et al. "KLT and Wavelet Filtering: Reducing Noise in Highly Accelerated Dynamic Images." (1 2012).
  • Johnson, D.; Chen, Z.; Ahmad, R.; Samouilov, A. et al. "Temporal Tomographic Imaging By Greedy Feteke and Golden Means Sampling." (1 2012).
  • Johnson, D, Chen, Z, Ahmad, R, Samouilov, A, Zweier, JL "Temporal Tomographic Imaging By Greedy Feteke and Golden Means Sampling." in ISMRM 20th Annual Meeting & Exhibition. (1 2012).

2011

  • Ahmad, R "Multisite EPR Oximetry using Multiple Field Modulation Harmonics." in 53rd Rocky Mountain Conference on Analytical Chemistry, 34th International EPR Symposium. (1 2011).
  • Ahmad, R.; Austin, C.D.; Potter, L.C. "Toeplitz embedding for fast iterative regularized imaging." (5 2011).
  • Ahmad, R, Austin, C, Potter, LC "Toeplitz embedding for fast iterative regularized imaging." in Proceedings SPIE: Algorithms for Synthetic Aperture Radar Imagery XVIII. (1 2011).
  • Ahmad, R. "Accelerated pH Imaging using electron paramagnetic resonance." (1 2011).
  • Ahmad, R. "Multisite EPR Oximetry using Multiple Field Modulation Harmonics." (1 2011).

2010

  • Ahmad, R, Kuppusamy, P, Potter, LC "Nested Uniform Sampling for Multiresolution 3-D Tomography." in 2010 IEEE International Conference on Acoustics, Speech and Signal Processing. (1 2010).
  • Ahmad, R.; Kuppusamy, P.; Potter, L.C.; IEEE, "NESTED UNIFORM SAMPLING FOR MULTIRESOLUTION 3-D TOMOGRAPHY." (1 2010).
  • Ahmad, R, Caia, G, Potter, LC, Petryakov, S, Kuppusamy, P, Zweier JL "In vivo oximetry using EPR-NRM coimaging." in A Joint Conference of the 14th In Vivo ESR/EPR Spectroscopy & Imaging and the 11th International EPR Spin Trapping/Spin Labeling. (1 2010).
  • Ahmad, R.; Caia, G.; Potter, L.C.; Petryakov, S. et al. "In vivo oximetry using EPR-NRM coimaging." (1 2010).
  • Som, S, Ahmad, R, Potter, LC, Kesselring, E, Kuppusamy, P, Zweier JL "A digital receiver for EPR spectroscopy." in A Joint Conference of 14th In Vivo ESR/EPR Spectroscopy & Imaging and the 11th International EPR Spin Trapping/Spin Labeling. (1 2010).
  • Ahmad, R.; Kuppusamy, P.; Potter, L.C. "Nested uniform sampling for multiresolution 3-D tomography." (11 2010).
  • Ahmad, R.; Kuppusamy, P.; Potter, L.C. "Nested uniform sampling for multiresolution 3-D tomography." (1 2010).
  • Som, S.; Ahmad, R.; Potter, L.C.; Kesselring, E. et al. "A digital receiver for EPR spectroscopy." (1 2010).
  • Ahmad, R.; Kuppusamy, P.; Potter, L.C. "NESTED UNIFORM SAMPLING FOR MULTIRESOLUTION 3-D TOMOGRAPHY." in 2010 IEEE International Conference on Acoustics, Speech, and Signal Processing. (1 2010).

2009

  • Ahmad, R, Potter, LC, Kuppusamy, P "Oscillating Radial Trajectories for Reduced Undersampling Artifacts." in ISMRM 17th Annual Meeting & Exhibition. (1 2009).
  • Ahmad, R.; Potter, L.; Kuppusamy, P. "Oscillating Radial Trajectories for Reduced Undersampling Artifacts." (1 2009).

2007

  • Ahmad, R.; Potter, L.C.; Clymer, B.; Zweier, J.L. et al. "Progressive uniform distribution of EPR data." (1 2007).
  • Ahmad, R, Vikram, DS, Clymer, B, Potter, LC, Srinivasan, P, Zweier, Jay L, Kuppusamy, P "Uniform Sampling for 4D Spectral-Spatial EPR Imaging." in A Joint Conference of 12th In Vivo EPR Spectroscopy and Imaging 9th International EPR Spin Trapping/Spin Labeling. (1 2007).
  • Som, S.; Potter, L.C.; Ahmad, R.; Kuppusamy, P. "Reduced Acquisition Spectral-Spatial EPR Oximetry." (1 2007).
  • Ahmad, R, Potter, LC, Clymer, B, Zweier, JL, Kuppusamy, P "Progressive uniform distribution of EPR data." in 49th Rocky Mountain Conference for Analytical Chemistry. (1 2007).
  • Som, S, Potter, LC, Ahmad, R, Kuppusamy, P "Reduced Acquisition Spectral-Spatial EPR Oximetry." in A Joint Conference of 12th In Vivo EPR Spectroscopy and Imaging 9th International EPR Spin Trapping/Spin Labeling. (1 2007).
  • Ahmad, R.; Vikram, D.S.; Clymer, B.; Potter, L.C. et al. "Uniform Sampling for 4D Spectral-Spatial EPR Imaging." (1 2007).

2006

  • Ahmad, R, Clymer, B, Deng, Y, Petryakov, S, Vikram, DS, Kuppusamy, P, Zweier, JL "An Automated On-The-Fly Detection and Correction Procedure for EPR Imaging Data Acquisition." in ISMRM 14th Annual Meeting & Exhibition. (1 2006).
  • Ahmad, R.; Clymer, B.; Deng, Y.; Petryakov, S. et al. "An Automated On-The-Fly Detection and Correction Procedure for EPR Imaging Data Acquisition." (1 2006).

2005

  • Ahmad, R.; Clymer, B.; Deng, Y.; He, G. et al. "Adaptive sampling for in vivo EPRI." (1 2005).
  • Ahmad, R.; Zweier, J.L.; Kuppusamy, P.; Clymer, B. "Adaptive Image Reconstruction for EPR." (1 2005).
  • Ahmad, R, Zweier, JL, Kuppusamy, P, Clymer, B "Adaptive Image Reconstruction for EPR." in ISMRM 13th Annual Meeting & Exhibition. (1 2005).
  • Ahmad, R, Clymer, B, Deng, Y, He, G, Vikram, DS, Kuppusamy, P, Zweier, JL "Adaptive sampling for in vivo EPRI." in International Conference on Electron Paramagnetic Resonance Spectroscopy and Imaging of Biological Systems. (1 2005).

Unknown

  • Ahmad, R, Jin, N, Simonetti, OP "Background Phase Correction for Quantitative Phase-Contrast MRI." in ISMRM 24th Annual Meeting & Exhibition.
  • Rich, A, Potter, LC, Jin, N, Serafim da Silveira, J, Simonetti, OP, Ahmad, R "Joint processing of highly accelerated multi-directional phase-contrast MRI using ReVEAL." in ISMRM 24th Annual Meeting & Exhibition.
  • Ahmad, R, Schroede, SA, White, RD, Kolipaka, A "Accelerated MR Elastography for Quantitative Measurement of Myocardial Stiffness." in ISMRM 24th Annual Meeting & Exhibition.

Patents

  • Kolipaka A, Ahmad R. "METHODS FOR CO-IMAGING TISSUE STIFFNESS AND BLOOD FLOW IN AN MRI SCAN."
  • Ahmad, R, Simonetti, OP, Potter, LC, Rich, A, Ting, ST. "Low-Field MRI Scanner for Cardiac Imaging."
  • Ahmad, R, Ding, Y, Simonetti, OP. "Variable Density Incoherent Constrained Sampling (VICS) for Highly Accelerated Magnetic Resonance Imaging."
  • Ahmad, R, Jin, N, Simonetti, OP. "Background Phase Correction for Quantitative Cardiovascular MRI."
  • Ding, Y, Ahmad, R, Simonetti, OP, Ting, S, Xue, H,. "Self-Constraint Non-Iterative GRAPPA Reconstruction with Closed-Form Solution."
  • Ahmad, R, Ding, Y, Ning, J, Simonetti, OP. "Direct Inversion for Phase-Based Dynamic Magnetic Resonance Measurement."
  • Simonetti, OP, Ahmad, R, Potter, LC, Varghese, J. "A Magnetic Resonance Imaging Method to Non-Invasively Measure Blood Oxygen Saturation."
  • Ahmad, R, Simonetti, OP, Potter, LC, Rich, A, Ting, ST. "Low-Field MRI Scanner for Cardiac Imaging." Patent number: 9,874,620
  • Ahmad,R, Ash, J, Jin, N, Potter, LC, Rich, AV, Simonetti, OP. "A Bayesian Model for Highly Accelerated Phase-Contrast MRI."
  • "A Bayesian model for highly accelerated phase-contrast MRI."
  • "Magnetic Resonance Imaging Method to Non-Invasively Measure Blood Oxygen Saturation."
  • Simonetti, OP, Ahmad, R, Potter, LC, Varghese, J. "Magnetic Resonance Imaging Method to Non-Invasively Measure Blood Oxygen Saturation."
  • Kolipaka A, Ahmad R. "Methods for Co-Imaging Tissue Stiffness and Blood Flow in an MRI."
  • "Methods for Co-Imaging Tissue Stiffness and Blood Flow in an MRI Scan."
  • Ahmad, R, Jin, N, Simonetti, OP. "Background Phase Correction for Quantitative Cardiovascular MRI." Patent number: 9,911,062
  • "Low-Field MRI Scanner for Cardiac Imaging."
  • "A Bayesian Model for Highly Accelerated Phase-Contrast MRI."
  • Ahmad, R, Ding, Y, Simonetti, OP. "Variable Density Incoherent Constrained Sampling (VICS) for Highly Accelerated Magnetic Resonance Imaging." Patent number: 9,939,509
  • "Variable Density Incoherent Costrained Sampling (VICS) for Highly Accelerated Magnetic Resonance Imaging."
  • "Variable Density Incoherent Spatial-Temporal Acquisition (VISTA) for Cardiac MR."
  • "Self-Constraint Non-Iterative GRAPPA Construction with Closed-Form Solution."
  • "Direct Inversion for Phase-Based Dynamic Magnetic Resonance Measurements."
  • "Electron Paramagnetic Resonance Systems and Methods for Transcutaneous and Subcutaneous Oxygen."
  • "METHOD AND SYSTEM FOR ELECTRON PARAMAGNETIC RESONANCE."
  • "Background Phase Correction for Quantitative Cardiovascular MRI."