Feasibility of Novel Three-Dimensional Magnetic Resonance Fingerprinting of the Prostate Gland: Phantom and Clinical Studies

Abstract

Objective To evaluate the feasibility of a new three-dimensional (3D) MR fingerprinting (MRF) technique for the prostate gland by conducting phantom and clinical studies. Materials and Methods The new 3D MRF technique used in this study enables quick data acquisition and has a high resolution. For the phantom study, the MRF T1 and T2 values in an in-house phantom were compared with those of gold-standard mapping methods using linear regression analysis. For the clinical study, we evaluated 90 patients who underwent prostate imaging with MRF for suspected prostate cancer between September 2019 and February 2020. The mean T1 and T2 values were compared in the peripheral zone, transition zone, and focal lesions using paired t tests. The differences in the T1 and T2 values according to cancer aggressiveness were evaluated using one-way analysis of variance. Results In the phantom study, the MRF T1 and T2 values showed a perfect correlation with the gold-standard T1 and T2 values (R > 0.99). In the clinical study, the T1 and T2 values in the peripheral zone were significantly higher than those in the transitional zone ( p < 0.001, both). The T1 and T2 values in prostate cancer were significantly lower than those in the peripheral and transitional zones. The higher the grade of cancer, the lower the T2 values. Conclusion The T1 and T2 values obtained from the 3D MRF showed a perfect correlation with the gold standard values in the phantom study. Differences in the T1 and T2 values among the different zones of the prostate gland were identified using 3D MRF in patients.

Magnetic Resonance Fingerprinting

“…Currently, a 2D acquisition is used, and each slice acquisition can take up to 50 seconds. Three-dimensional prostate MRF acquisition would accelerate acquisition and also produce higher-resolution images and is currently being investigated with initial promising results 101–103 …”

“…Three-dimensional prostate MRF acquisition would accelerate acquisition and also produce higher-resolution images and is currently being investigated with initial promising results. [101][102][103]…”

Current Applications and Future Development of Magnetic Resonance Fingerprinting in Diagnosis, Characterization, and Response Monitoring in Cancer

“…MRF T1 and ADC values were found to be complementary for malignant lesion staging, whereas there was an overlap in MRF T2 values between different lesion types [ 64 ]. Han et al recently used 3D MRF in phantoms and 90 patients with suspected prostate cancer [ 65 ]. Findings were consistent with the results from 2D MRF trials for prostate cancer, and the image acquisition protocol provided faster coverage of the entire prostate gland (4 min rather than 7–8 min).…”

Editorial for “Value of T2 Mapping MRI for Prostate Cancer Detection and Classification”

“…4 In the MR fingerprinting technique, T1 mapping and T2 mapping can be obtained by postprocessing the data that had been acquired while changing the flip angle and echo time for about 5 minutes. 5 In this issue of JMRI, the article "Value of T2 mapping for prostate cancer detection and classification" showed that prostate cancer and surrounding tissues were well distinguished in the T2 mapping image. The average T2 relaxation time of prostate cancer was 85 msec in the peripheral zone (PZ) and 75 msec in the transition zone (TZ), and authors suggested 92 msec as a cut-off value for diagnosing prostate cancer.…”

“…Nowadays, T2 mapping can be done within 5 minutes by using methods such as parallel imaging and model‐based reconstruction method which gives more than 15 different TE values 4 . In the MR fingerprinting technique, T1 mapping and T2 mapping can be obtained by postprocessing the data that had been acquired while changing the flip angle and echo time for about 5 minutes 5 …”