Current Role at Stanford

Research Associate


Education & Certifications

  • PhD, University of Wisconsin-Madison, Medical Physics (2009)
  • MS, University of Wisconsin-Madison, Medical Physics (2006)
  • BA, University of Chicago, Physics (1997)


All Publications

  • Editorial for "Investigation of synthetic relaxometry and diffusion measures in the differentiation of benign and malignant breast lesions as compared to BI-RADS". Journal of magnetic resonance imaging : JMRI Moran, C. J. 2020

    View details for DOI 10.1002/jmri.27480

    View details for PubMedID 33345382

  • Multishot Diffusion-Weighted MRI of the Breast With Multiplexed Sensitivity Encoding (MUSE) and Shot Locally Low-Rank (Shot-LLR) Reconstructions. Journal of magnetic resonance imaging : JMRI Hu, Y., Ikeda, D. M., Pittman, S. M., Samarawickrama, D., Guidon, A., Rosenberg, J., Chen, S., Okamoto, S., Daniel, B. L., Hargreaves, B. A., Moran, C. J. 2020


    BACKGROUND: Diffusion-weighted imaging (DWI) has shown promise to screen for breast cancer without a contrast injection, but image distortion and low spatial resolution limit standard single-shot DWI. Multishot DWI methods address these limitations but introduce shot-to-shot phase variations requiring correction during reconstruction.PURPOSE: To investigate the performance of two multishot DWI reconstruction methods, multiplexed sensitivity encoding (MUSE) and shot locally low-rank (shot-LLR), compared to single-shot DWI in the breast.STUDY TYPE: Prospective.POPULATION: A total of 45 women who consented to have multishot DWI added to a clinically indicated breast MRI.FIELD STRENGTH/SEQUENCES: Single-shot DWI reconstructed by parallel imaging, multishot DWI with four or eight shots reconstructed by MUSE and shot-LLR, 3D T2 -weighted imaging, and contrast-enhanced MRI at 3T.ASSESSMENT: Three blinded observers scored images for 1) general image quality (perceived signal-to-noise ratio [SNR], ghosting, distortion), 2) lesion features (discernment and morphology), and 3) perceived resolution. Apparent diffusion coefficient (ADC) of the lesion was also measured and compared between methods.STATISTICAL TESTS: Image quality features and perceived resolution were assessed with a mixed-effects logistic regression. Agreement among observers was estimated with a Krippendorf's alpha using linear weighting. Lesion feature ratings were visualized using histograms, and correlation coefficients of lesion ADC between different methods were calculated.RESULTS: MUSE and shot-LLR images were rated to have significantly better perceived resolution (P<0.001), higher SNR (P<0.005), and a lower level of distortion (P<0.05) with respect to single-shot DWI. Shot-LLR showed reduced ghosting artifacts with respect to both MUSE (P<0.001) and single-shot DWI (P<0.001). Eight-shot DWI had improved perceived SNR and perceived resolution with respect to four-shot DWI (P<0.005).DATA CONCLUSION: Multishot DWI enables increased resolution and improved image quality with respect to single-shot DWI in the breast. Shot-LLR reconstructs multishot DWI with minimal ghosting artifacts. The improvement of multishot DWI in image quality increases with an increased number of shots.LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.

    View details for DOI 10.1002/jmri.27383

    View details for PubMedID 33067849

  • RUN-UP: Accelerated multishot diffusion-weighted MRI reconstruction using an unrolled network with U-Net as priors. Magnetic resonance in medicine Hu, Y. n., Xu, Y. n., Tian, Q. n., Chen, F. n., Shi, X. n., Moran, C. J., Daniel, B. L., Hargreaves, B. A. 2020


    To accelerate and improve multishot diffusion-weighted MRI reconstruction using deep learning.An unrolled pipeline containing recurrences of model-based gradient updates and neural networks was introduced for accelerating multishot DWI reconstruction with shot-to-shot phase correction. The network was trained to predict results of jointly reconstructed multidirection data using single-direction data as input. In vivo brain and breast experiments were performed for evaluation.The proposed method achieves a reconstruction time of 0.1 second per image, over 100-fold faster than a shot locally low-rank reconstruction. The resultant image quality is comparable to the target from the joint reconstruction with a peak signal-to-noise ratio of 35.3 dB, a normalized root-mean-square error of 0.0177, and a structural similarity index of 0.944. The proposed method also improves upon the locally low-rank reconstruction (2.9 dB higher peak signal-to-noise ratio, 29% lower normalized root-mean-square error, and 0.037 higher structural similarity index). With training data from the brain, this method also generalizes well to breast diffusion-weighted imaging, and fine-tuning further reduces aliasing artifacts.A proposed data-driven approach enables almost real-time reconstruction with improved image quality, which improves the feasibility of multishot DWI in a wide range of clinical and neuroscientific studies.

    View details for DOI 10.1002/mrm.28446

    View details for PubMedID 32783339

  • Motion-robust reconstruction of multishot diffusion-weighted images without phase estimation through locally low-rank regularization MAGNETIC RESONANCE IN MEDICINE Hu, Y., Levine, E. G., Tian, Q., Moran, C. J., Wang, X., Taviani, V., Vasanawala, S. S., Mcnab, J. A., Daniel, B. L., Hargreaves, B. A. 2019; 81 (2): 1181–90

    View details for DOI 10.1002/mrm.27488

    View details for Web of Science ID 000462086300038

  • Near-silent distortionless DWI using magnetization-prepared RUFIS. Magnetic resonance in medicine Yuan, J. n., Hu, Y. n., Menini, A. n., Sandino, C. M., Sandberg, J. n., Sheth, V. n., Moran, C. J., Alley, M. n., Lustig, M. n., Hargreaves, B. n., Vasanawala, S. n. 2019


    To develop a near-silent and distortionless DWI (sd-DWI) sequence using magnetization-prepared rotating ultrafast imaging sequence.A rotating ultrafast imaging sequence was modified with driven-equilibrium diffusion preparation, including eddy-current compensation methods. To compensate for the T1 recovery during readout, a phase-cycling method was used. Both compensation methods were validated in phantoms. The optimized sequence was compared with an EPI diffusion sequence for image distortion, contrast, ADC, and acoustic noise level in phantoms. The sequence was evaluated in 1 brain volunteer, 5 prostate volunteers, and 10 pediatric patients with joint diseases.Combination of several eddy-current compensation methods reduced the artifact to an acceptable level. Phase cycling reduced T1 recovery contamination during readout. In phantom scans, the optimized sequence generated similar image contrast to the EPI diffusion sequence, and ADC maps between the sequences were comparable; sd-DWI had significantly lower acoustic noise (P < .05). In vivo brain scan showed reduced image distortion in sd-DWI compared with the EPI diffusion, although residual motion artifact remains due to brain pulsation. The prostate scans showed that sd-DWI can provide similar ADC compared with EPI diffusion, with no image distortion. Patient scans showed that the sequence can clearly depict joint lesions.An sd-DWI sequence was developed and optimized. Compared with conventional EPI diffusion, sd-DWI provided similar diffusion contrast, accurate ADC measurement, improved image quality, and minimal ambient scanning noise. The sequence showed the ability to obtain in vivo diffusion contrast in relatively motion-free body regions, such as prostate and joint.

    View details for DOI 10.1002/mrm.28106

    View details for PubMedID 31782557

  • Motion-robust reconstruction of multishot diffusion-weighted images without phase estimation through locally low-rank regularization. Magnetic resonance in medicine Hu, Y., Levine, E. G., Tian, Q., Moran, C. J., Wang, X., Taviani, V., Vasanawala, S. S., McNab, J. A., Daniel, B. A., Hargreaves, B. L. 2018


    PURPOSE: The goal of this work is to propose a motion robust reconstruction method for diffusion-weighted MRI that resolves shot-to-shot phase mismatches without using phase estimation.METHODS: Assuming that shot-to-shot phase variations are slowly varying, spatial-shot matrices can be formed using a local group of pixels to form columns, in which each column is from a different shot (excitation). A convex model with a locally low-rank constraint on the spatial-shot matrices is proposed. In vivo brain and breast experiments were performed to evaluate the performance of the proposed method.RESULTS: The proposed method shows significant benefits when the motion is severe, such as for breast imaging. Furthermore, the resulting images can be used for reliable phase estimation in the context of phase-estimation-based methods to achieve even higher image quality.CONCLUSION: We introduced the shot-locally low-rank method, a reconstruction technique for multishot diffusion-weighted MRI without explicit phase estimation. In addition, its motion robustness can be beneficial to neuroimaging and body imaging.

    View details for PubMedID 30346058

  • connective tissues in the knee using ultrashort echo-time double-echo steady-state (UTEDESS). Magnetic resonance in medicine Chaudhari, A. S., Sveinsson, B., Moran, C. J., McWalter, E. J., Johnson, E. M., Zhang, T., Gold, G. E., Hargreaves, B. A. 2017


    To develop a radial, double-echo steady-state (DESS) sequence with ultra-short echo-time (UTE) capabilities for T2 measurement of short-T2 tissues along with simultaneous rapid, signal-to-noise ratio (SNR)-efficient, and high-isotropic-resolution morphological knee imaging.THe 3D radial UTE readouts were incorporated into DESS, termed UTEDESS. Multiple-echo-time UTEDESS was used for performing T2 relaxometry for short-T2 tendons, ligaments, and menisci; and for Dixon water-fat imaging. In vivo T2 estimate repeatability and SNR efficiency for UTEDESS and Cartesian DESS were compared. The impact of coil combination methods on short-T2 measurements was evaluated by means of simulations. UTEDESS T2 measurements were compared with T2 measurements from Cartesian DESS, multi-echo spin-echo (MESE), and fast spin-echo (FSE).UTEDESS produced isotropic resolution images with high SNR efficiency in all short-T2 tissues. Simulations and experiments demonstrated that sum-of-squares coil combinations overestimated short-T2 measurements. UTEDESS measurements of meniscal T2 were comparable to DESS, MESE, and FSE measurements while the tendon and ligament measurements were less biased than those from Cartesian DESS. Average UTEDESS T2 repeatability variation was under 10% in all tissues.The T2 measurements of short-T2 tissues and high-resolution morphological imaging provided by UTEDESS makes it promising for studying the whole knee, both in routine clinical examinations and longitudinal studies. Magn Reson Med, 2017. © 2017 International Society for Magnetic Resonance in Medicine.

    View details for DOI 10.1002/mrm.26577

    View details for PubMedID 28074498

  • Comparison of Magnetic Resonance Imaging and Computed Tomography for Breast Target Volume Delineation in Prone and Supine Positions INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS Pogson, E. M., Delaney, G. P., Ahern, V., Boxer, M. M., Chan, C., David, S., Dimigen, M., Harvey, J. A., Koh, E., Lim, K., Papadatos, G., Yap, M. L., Batumalai, V., Lazarus, E., Dundas, K., Shafiq, J., Liney, G., Moran, C., Metcalfe, P., Holloway, L. 2016; 96 (4): 905-912


    To determine whether T2-weighted MRI improves seroma cavity (SC) and whole breast (WB) interobserver conformity for radiation therapy purposes, compared with the gold standard of CT, both in the prone and supine positions.Eleven observers (2 radiologists and 9 radiation oncologists) delineated SC and WB clinical target volumes (CTVs) on T2-weighted MRI and CT supine and prone scans (4 scans per patient) for 33 patient datasets. Individual observer's volumes were compared using the Dice similarity coefficient, volume overlap index, center of mass shift, and Hausdorff distances. An average cavity visualization score was also determined.Imaging modality did not affect interobserver variation for WB CTVs. Prone WB CTVs were larger in volume and more conformal than supine CTVs (on both MRI and CT). Seroma cavity volumes were larger on CT than on MRI. Seroma cavity volumes proved to be comparable in interobserver conformity in both modalities (volume overlap index of 0.57 (95% Confidence Interval (CI) 0.54-0.60) for CT supine and 0.52 (95% CI 0.48-0.56) for MRI supine, 0.56 (95% CI 0.53-0.59) for CT prone and 0.55 (95% CI 0.51-0.59) for MRI prone); however, after registering modalities together the intermodality variation (Dice similarity coefficient of 0.41 (95% CI 0.36-0.46) for supine and 0.38 (0.34-0.42) for prone) was larger than the interobserver variability for SC, despite the location typically remaining constant.Magnetic resonance imaging interobserver variation was comparable to CT for the WB CTV and SC delineation, in both prone and supine positions. Although the cavity visualization score and interobserver concordance was not significantly higher for MRI than for CT, the SCs were smaller on MRI, potentially owing to clearer SC definition, especially on T2-weighted MR images.

    View details for DOI 10.1016/j.ijrobp.2016.08.002

    View details for PubMedID 27788960

  • Rim Sign in Breast Lesions on Diffusion-Weighted Magnetic Resonance Imaging: Diagnostic Accuracy and Clinical Usefulness JOURNAL OF MAGNETIC RESONANCE IMAGING Kang, B. J., Lipson, J. A., Planey, K. R., Zackrisson, S., Ikeda, D. M., Kao, J., Pal, S., Moran, C. J., Daniel, B. L. 2015; 41 (3): 616-623


    To investigate the diagnostic accuracy and clinical usefulness of the rim sign in breast lesions observed in diffusion-weighted magnetic resonance imaging (DWI).The magnetic resonance imaging (MRI) findings of 98 pathologically confirmed lesions (62 malignant and 36 benign) in 84 patients were included. Five breast radiologists were asked to independently review the breast MRI results, to grade the degree of high peripheral signal, the "rim sign," in the DWI, and to confirm the mean apparent diffusion coefficient (ADCmean ) values. We analyzed the diagnostic accuracy and compared the consensus (when ≥4 of 5 independent reviewers agreed) results of the rim sign with the ADCmean values. Additionally, we evaluated the correlation between the dynamic contrast-enhanced (DCE)-MRI morphologic appearance and DWI rim sign.According to the consensus results, the rim sign in DWI was observed on 59.7% of malignant lesions and 19.4% of benign lesions. The sensitivity, specificity, and area under the curve (AUC) value for the rim sign in DWI were 59.7%, 80.6%, and 0.701, respectively. The sensitivity, specificity, and AUC value for the ADCmean value (criteria ≤1.46 × 10(-3) mm(2) /sec) were 82.3%, 63.9%, and 0.731, respectively. Based on consensus, no correlation was observed between the DCE-MRI and DWI rim signs.In DWI, a high-signal rim is a valuable morphological feature for improving specificity in DWI.J. Magn. Reson. Imaging 2014. © 2014 Wiley Periodicals, Inc.

    View details for DOI 10.1002/jmri.24617

    View details for Web of Science ID 000349967700006

    View details for PubMedID 24585455

  • 3D T2-Weighted Spin Echo Imaging in the Breast JOURNAL OF MAGNETIC RESONANCE IMAGING Moran, C. J., Hargreaves, B. A., Saranathan, M., Lipson, J. A., Kao, J., Ikeda, D. M., Daniel, B. L. 2014; 39 (2): 332-338


    PURPOSE: To evaluate the performance of 2D versus 3D T2-weighted spin echo imaging in the breast. MATERIALS AND METHODS: 2D and 3D T2-weighted images were acquired in 25 patients as part of a clinically indicated breast magnetic resonance imaging (MRI) exam. Lesion-to-fibroglandular tissue signal ratio was measured in 16 identified lesions. Clarity of lesion morphology was assessed through a blinded review by three radiologists. Instances demonstrating the potential diagnostic contribution of 3D versus 2D T2-weighted imaging in the breast were noted through unblinded review by a fourth radiologist. RESULTS: The lesion-to-fibroglandular tissue signal ratio was well correlated between 2D and 3D T2-weighted images (R(2)  = 0.93). Clarity of lesion morphology was significantly better with 3D T2-weighted imaging for all observers based on a McNemar test (P ≤ 0.02, P ≤ 0.01, P ≤ 0.03). Instances indicating the potential diagnostic contribution of 3D T2-weighted imaging included improved depiction of signal intensity and improved alignment between DCE and T2-weighted findings. CONCLUSION: In this pilot study, 3D T2-weighted imaging provided comparable contrast and improved depiction of lesion morphology in the breast in comparison to 2D T2-weighted imaging. Based on these results further investigation to determine the diagnostic impact of 3D T2-weighted imaging in breast MRI is warranted.J. Magn. Reson. Imaging 2013;00:000-000. © 2013 Wiley Periodicals, Inc.

    View details for DOI 10.1002/jmri.24151

    View details for Web of Science ID 000329753400011

    View details for PubMedID 23596017

  • High-Resolution 3D Radial bSSFP with IDEAL MAGNETIC RESONANCE IN MEDICINE Moran, C. J., Brodsky, E. K., Bancroft, L. H., Reeder, S. B., Yu, H., Kijowski, R., Engel, D., Block, W. F. 2014; 71 (1): 95-104


    Radial trajectories facilitate high-resolution balanced steady state free precession (bSSFP) because the efficient gradients provide more time to extend the trajectory in k-space. A number of radial bSSFP methods that support fat-water separation have been developed; however, most of these methods require an environment with limited B0 inhomogeneity. In this work, high-resolution bSSFP with fat-water separation is achieved in more challenging B0 environments by combining a 3D radial trajectory with the IDEAL chemical species separation method. A method to maintain very high resolution within the timing constraints of bSSFP and IDEAL is described using a dual-pass pulse sequence. The sampling of a unique set of radial lines at each echo time is investigated as a means to circumvent the longer scan time that IDEAL incurs as a multiecho acquisition. The manifestation of undersampling artifacts in this trajectory and their effect on chemical species separation are investigated in comparison to the case in which each echo samples the same set of radial lines. This new bSSFP method achieves 0.63 mm isotropic resolution in a 5-min scan and is demonstrated in difficult in vivo imaging environments, including the breast and a knee with ACL reconstruction hardware at 1.5 T.

    View details for DOI 10.1002/mrm.24633

    View details for Web of Science ID 000328580300012

    View details for PubMedID 23504943

    View details for PubMedCentralID PMC3762898

  • Image quality and diagnostic performance of silicone-specific breast MRI. Magnetic resonance imaging Kim, S. H., Lipson, J. A., Moran, C. J., Shimakawa, A., Kuo, J., Ikeda, D. M., Daniel, B. L. 2013; 31 (9): 1472-1478


    To compare the image quality of three techniques and diagnostic performance in detecting implant rupture.The study included 161 implants for the evaluation of image quality, composed of water-saturated short TI inversion recovery (herein called "water-sat STIR"), three-point Dixon techniques (herein called "Dixon"), and short TI inversion recovery fast spin-echo with iterative decomposition of silicone and water using least-squares approximation (herein called "STIR IDEAL") and included 41 implants for the evaluation of diagnostic performance in detecting rupture, composed of water-sat STIR and STIR IDEAL. Six image quality categories were evaluated and three classifications were used: normal implant, possible rupture, and definite rupture.Statistically significant differences were noted for the image quality categories (p<0.001). STIR IDEAL was superior or equal to water-sat STIR in all image quality categories except artifact effects and superior to Dixon in all categories. Water-sat STIR performed the poorest for water suppression uniformity. The sensitivity and specificity in detecting implant rupture of STIR-IDEAL were 81.8 % and 77.8 % and the difference between two techniques was not statistically significant.STIR-IDEAL is a useful silicone-specific imaging technique demonstrating more robust water suppression and equivalent diagnostic accuracy for detecting implant rupture, than water-sat STIR, at the cost of longer scan time and an increase in minor motion artifacts.

    View details for DOI 10.1016/j.mri.2013.05.011

    View details for PubMedID 23895871

  • High resolution images of the breast. European journal of radiology Moran, C. J., Saranathan, M., Nnewihe, A. N., Granlund, K. L., Alley, M. T., Daniel, B. L., Hargreaves, B. A. 2012; 81: S101-3

    View details for DOI 10.1016/S0720-048X(12)70041-4

    View details for PubMedID 23083546

  • Breast MRI without gadolinium: utility of 3D DESS, a new 3D diffusion weighted gradient-echo sequence. European journal of radiology Daniel, B. L., Granlund, K. L., Moran, C. J., Alley, M. T., Lipson, J., Ikeda, D. M., Kao, J., Hargreaves, B. A. 2012; 81: S24-6

    View details for DOI 10.1016/S0720-048X(12)70010-4

    View details for PubMedID 23083590

  • Pilot Study of Improved Lesion Characterization in Breast MRI Using a 3D Radial Balanced SSFP Technique With Isotropic Resolution and Efficient Fat-Water Separation JOURNAL OF MAGNETIC RESONANCE IMAGING Moran, C. J., Kelcz, F., Jung, Y., Brodsky, E. K., Fain, S. B., Block, W. F. 2009; 30 (1): 135-144


    To assess a 3D radial balanced steady-state free precession (SSFP) technique that provides submillimeter isotropic resolution and inherently registered fat and water image volumes in comparison to conventional T2-weighted RARE imaging for lesion characterization in breast magnetic resonance imaging (MRI).3D projection SSFP (3DPR-SSFP) combines a dual half-echo radial k-space trajectory with a linear combination fat/water separation technique (linear combination SSFP). A pilot study was performed in 20 patients to assess fat suppression and depiction of lesion morphology using 3DPR-SSFP. For all patients fat suppression was measured for the 3DPR-SSFP image volumes and depiction of lesion morphology was compared against corresponding T2-weighted fast spin echo (FSE) datasets for 15 lesions in 11 patients.The isotropic 0.63 mm resolution of the 3DPR-SSFP sequence demonstrated improved depiction of lesion morphology in comparison to FSE. The 3DPR-SSFP fat and water datasets were available in a 5-minute scan time while average fat suppression with 3DPR-SSFP was 71% across all 20 patients.3DPR-SSFP has the potential to improve the lesion characterization information available in breast MRI, particularly in comparison to conventional FSE. A larger study is warranted to quantify the effect of 3DPR-SSFP on specificity.

    View details for DOI 10.1002/jmri.21807

    View details for Web of Science ID 000267452600017

    View details for PubMedID 19557728

    View details for PubMedCentralID PMC3743726

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