Click here to


Are you sure ?

Yes, do it No, cancel

Feasibility of Achieving T2w Super-Resolution Time-Resolved (TR) 4DMRI Using T1w TR-4DMRI as the Guidance

G Li1*, X Nie2 , M Kadbi3 , Z Saleh4 , K Zakian5 , J Mechalakos6 , M Hunt7 , J Deasy8 , A Rimner9 , (1) Memorial Sloan Kettering Cancer Center, New York, NY, (2) Memorial Slona Kettering Cancer Center, New York, NY, (3) Philips Healthcare, Cleveland, OH, (4) Memorial Sloan Kettering West Harrison, West Harrison, NY, (5) Memorial Sloan-Kettering Cancer Center, New York, New York, (6) Memorial Sloan-Kettering Cancer Center, New York, NY, (7) Memorial Sloan Kettering Cancer Center, New York, NY, (8) Memorial Sloan Kettering Cancer Center, New York, NY, (9) Memorial Sloan Kettering Cancer center, New York, NY


(Tuesday, 7/31/2018) 1:15 PM - 1:45 PM

Room: Exhibit Hall | Forum 2

Purpose: After a success in developing super-resolution (SR) time-resolved (TR) 4DMRI, we plan to extend the SR approach to reconstruct T2w TR-4DMRI with higher soft-tissue contrast using deformable image registration (DIR) to facilitate clinical applications for multi-breath motion assessment and tumor delineation.

Methods: The SR-based T1w TR-4DMRI was reconstructed by deforming a high-resolution (2x2x2mm³) breath-hold (BH) 3DMRI image to a series of low-resolution (5x5x5mm³) 3D cine images at a 2Hz frame rate in free breathing (FB). The deformation vector fields (DVFᵀ¹ʷ�ᴰ) was saved. To achieve SR-based T2w TR-4DMRI, we developed two approaches. In the first method, a high-resolution (2x2x2mm³) T2w 3DMRI image was acquired, deformed to the T1w BH image, and this DVFᵀ²ʷᴴᴿ was combined with DVFᵀ¹ʷ�ᴰ to reconstruct T2w TR-4DMRI. In the second method, the DIR was reversed with DVFᵀ¹ʷᴴᴿ (=[DVFᵀ²ʷᴴᴿ]�¹), the deformed T1w BH was used to reconstruct the T1w TR-4DMRI, and the new combined DVFs were used to reconstruct T2w TR-4DMRI. Two lung cancer patients from an IRB-approved protocol were selected for this feasibility study. To acquire the high-resolution 3DMRI image, we applied a navigator-triggered respiratory-correlated 4DMRI scanning protocol to acquire 3-bin images (full-exhalation, mid-inhalation, and full-inhalation) with minimal binning artifacts. The closest T2w 3DMRI to a T1w BH was used with minimal deformation. The tumor alignment among the 3D cine, T1w and T2w TR-4DMRI was compared.

Results: Excellent tumor alignment is achieved for T2w TR-4DMRI within 2mm, like T1w TR-4DMRI. The first method is convenient since the existing DVFT1w4D can be borrowed from T1w TR-4DMRI reconstruction, while the second method has the advantage of keeping the T2w tumor volume.

Conclusion: The feasibility of T2w TR-4DMRI reconstruction has been demonstrated. The image alignment in low soft-tissue contrast is adequate. A further study with more patients is ongoing to fully characterize T2w TR-4DMRI image quality for clinical applications.

Funding Support, Disclosures, and Conflict of Interest: The Memorial Sloan Kettering cancer center has a master research agreement with Philips Healthcare


Respiration, MRI, Radiation Therapy



Contact Email