Abstract
Background
Little is known of the influence of scanner field strength on quantitative diffusivity variables, especially kurtosis in healthy ovaries.
Purpose
To evaluate the influence of scanner field strength on quantitative diffusion variables in pelvic MRI of the ovaries.
Material and Methods
This prospective, single-centre study consisted of repeated 1.5-T and 3-T examinations in 30 female volunteers (mean age=27.9 years, age range=20.3–45.2 years) from July 2017 to September 2019. Multi b-value DWI 0, 50, 100, 800, 1500, 2000 s/mm2 was acquired over three timepoints during the menstrual cycle. Ovaries were segmented at b = 1500 s/mm2. Median apparent diffusion coefficient (ADC) and advanced kurtosis parameters Dapp and Kapp were calculated. Statistical analysis was performed with the variations of diffusivity variables being compared between 1.5-T and 3-T MRI using a Mann–Whitney rank-sum test.
Results
Median ADC and Dapp (µm²/ms) did not statistically differ. Median ADC were 1.509 (range=1.371–1.610), 1.619 (range=1.463–1.747), and 1.511 (range=1.423–1.639) at 1.5 T; 1.542 (range=1.428–1.682), 1.658 (range=1.510–1.806), and 1.572 (range=1.455–1.709) at 3 T (P = 0.14, 0.19, and 0.07), whereas median Dapp were 2.024 (range=1.913–2.152), 2.192 (range=2.010–2.327), and 2.045 (range=1.958–2.170) at 1.5 T; 2.013 (range=1.952–2.188), 2.179 (range=2.018–2.327), and 2.082 (range=1.959–2.194) at 3 T (P = 0.77, 0.99, and 0.34) for timepoints 1, 2, and 3, respectively. Statistical comparison of Kapp revealed significant differences for all timepoints: 0.629 (range=0.595–0.652), 0.604 (range=0.574–0.651), and 0.622 (range=0.581–0.664) at 1.5 T; 0.601 (range=0.563–0.626), 0.567 (range=0.526–0.633), and 0.599 (range=0.541–0.650) at 3 T (P < 0.001, 0.005, and 0.03).
Conclusion
Diffusivity mapping in the ovaries provides similar absolute median diffusion values, but statistically significant differences in absolute kurtosis values between 1.5 T and 3 T.
Get full access to this article
View all access options for this article.
References
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
