1. A reproducibility study was conducted using a novel ultra-short echo time 31P 3D MRSI sequence with a rosette k-space trajectory at 3T across three different sites. 2. Five healthy volunteers were scanned at each site using slightly different coil configurations, and similar metabolite maps were achieved with a coefficient of variance of around 10% for total ATP/PCr across sites. 3. The study demonstrated that the highly accelerated technique improved 31P MRSI acquisitions by achieving high-resolution metabolite maps with excellent spectral quality consistently across sites.

1. Ultra-Short Echo Time 31P 3D
MRSI at 3Twith Novel Rosette
k-space Trajectory
Team Name: UTE 31P 3D Rosette MRS Reproducibility
Original Authors: Uzay E Emir
Reproducers: Ulrich Pilatus, Goethe University Frankfurt
Seyma Alcicek, Goethe University Frankfurt
Alexander Richard Craig-Craven, University of Bergen

2. UTE 31P 3D Rosette MRS
Reproducibility (Why do we need?)
● The first human MRS study and MRS of disease used ³¹P MRS (the 1980s)
● The oldest yet still unattractive ,
31P MRS is Unattractive
• A lack of technical development
and integration into clinical MRI
systems
• Low SNR
• poor spatial resolution
• long acquisition time
• Lack of processing software
available for automated
quantification of the metabolites
31P MRS is the most attractive
• Increased SNR
• Increased Resolution
• Short acquisition duration
• Automated quantification of the
metabolites

3. UTE 31P 3D Rosette MRS
Reproducibility (Networking)
https://github.com/uzayemir/31P-MRSI
https://purr.purdue.edu/projects/ismrm31pmrsi
https://forum.mrshub.org/
https://twitter.com/uzemye https://www.youtube.com/uzayemir1
https://challenge.ismrm.org

4. UTE 31P 3D Rosette MRS
Reproducibility (Outcomes)
● In 3 Sites, five healthy volunteers were scanned at each site
● 2 Prisma 3T and an mMR (PET-MRI) with RAPID Biomedical Coils
● Purdue University Dual Tuned Surface Coil,
● The University of Bergen, Dual Tuned Quadrature Head Coil
● Goethe-University, Dual Tuned Quadrature Head Coil.
1. An MRSI acquisition with a TE of 50 μs was developed.
2. The replication study demonstrates that the highly accelerated
technique has improved the novel 31P MRSI acquisitions.
3. Improved the LCModel fitting.
4. Similar metabolite maps were achieved in healthy subjects.
5. High-resolution (10 mm3) with Excellent spectral quality was
consistently achieved with negligible baseline and phase
distortion.
6. Three sites successfully achieve a coefficient of variance of
around 10 % for total ATP/PCr.

5. UTE 31P 3D Rosette MRS
Reproducibility (Experiences)
● The only minor limitation is that there is no possibility of instantly checking the spectral data quality
at the workstation due to the need to perform an offline reconstruction pipeline. But it should also be
mentioned that this pipeline was straightforward and convenient.
● The outcomes of this challenge attest to the basic efficacy and reliability of the sequence..
UTE 31P 3D Rosette MRS Reproducibility Challenge make 31P MRS a
clinically viable option, and it is now appropriate to develop and
evaluate protocols suitable for clinical practice and use them to
investigate metabolism.

6. References
1. Cresshull ID, Gordon RE, Hanley PE, et al. Localization of metabolites in animal and human
tissue using ³¹P topical magnetic resonance. Bull Magnet Reson 1980; 2:426. (First MRS
spectrum recorded in a human forearm.)
2. Ross BD, Radda GK, Gadian DG, et al. Examination of a case of suspected McArdle's
syndrome by ³¹P nuclear magnetic resonance. N Engl J Med 1981; 304:1338-1342. (First
application of MRS to human disease.)
3. Shen X, Ozen AC, Monsivais H, Sunjar A, Ilbey S, Zheng W, Du Y, Chiew M, Emir UE. High-
Resolution 3D Ultra-Short Echo Time MRI with Rosette k-Space Pattern for Brain Iron Content
Mappin. Journal of Trace Elements in Medicine and Biology, 2023.
4. Shen X, Özen AC, Sunjar A, Ilbey S, Sawiak S, Shi R, Chiew M, Emir UE. Ultra-short T2
components imaging of the whole brain using 3D dual-echo UTE MRI with rosette k-space
pattern. Magnetic Resonance in Medicine. 2023;89(2):508–521. PubMed PMID: 36161728.
5. Bozymski B, Shen X, Ozen AC, Ibey S, Chiew M, Thomas A, Dydak U, Emir UE. Ultra-
Short Echo Time 31P 3D MRSI at 3T with Novel Rosette k-space Trajectory. Proceedings
30th Scientific Meeting, International Society for Magnetic Resonance in Medicine, 2022