Super-fast 3T Prostate MRI Using High Gradient Strength and Deep Learning: Initial Experience
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Enrollment
- 77
- Locations
- 1
- Primary Endpoint
- Acquisition time
Study Overview
Brief Summary
Recent developments in MRI techniques allow ultra-high gradient strength diffusion imaging and deep learning (DL) reconstruction in clinical routine. However, its usability in biparametric MRI (bpMRI) of the prostate has not been well studied. The aim is to establish a super-fast 3-minutes bpMRI protocol at 3 Tesla using high gradient strength and DL reconstruction and compare it against a full, multiparametric MRI (mpMRI) protocol.
Detailed Description
Multiparametric MRI (mpMRI) of the prostate has become the most important non-invasive diagnostic tool for assessment of prostate cancer and is the baseline for MRI targeted biopsy (1,2). As the incidence of prostate cancer is high with an estimated 290,000 new cases for 2023 in the United States alone (3), the need for widespread provision of prostate mpMRI is immense. However, current clinical MRI-protocols are long with acquisition times of >30 minutes, potentially limiting the number of examined patients. According to the guidelines of the Prostate Imaging Reporting and Data System (PI-RADS) a sufficient mpMRI protocol must include diffusion weighted imaging (DWI), T2-weighted (T2w) imaging, dynamic contrast enhanced imaging and T1-weighted imaging pre and post administration of contrast (4,5). Different approaches have been developed to shorten the protocol itself or to accelerate acquisition times. For instance, a significant reduction of T2w-sequence acquisition times was achieved by employing deep learning methods (6) or advancements of compressed sensing (7), while at the same time images had improved quality. Different studies showed equal performance of biparametric MRI (bpMRI) protocols compared to the standard multiparametric protocol, effectively reducing the acquisition time down to 5 minutes (8,9,10). This was done by focusing only on DWI and T2w imaging while omitting the dynamic contrast enhanced sequence and T1-weighted sequences, as the additional diagnostic value of these is supposed to be limited (11).
Recent developments in MRI techniques allow for ultra-high diffusion gradient strengths of up to 500 mT/m and slew rates of up to 600 T/m/s, thus reducing echo times and acquisition times by faster establishment of the diffusion gradient (12,13). Furthermore, these gradients are able to image at small scales with a high signal-to-noise ratio, consecutively enhancing sensitivity for detection of tissue microstructures (14,15). Due to the experimental nature of these gradients, this technique has only been investigated in a research setting in healthy volunteers (16), but not in a real world clinical setting, let alone in prostate imaging.
Therefore, the aim of the study was to establish a super-fast abbreviated bpMRI protocol for patients with suspicion for prostate cancer using both ultra-high gradients and deep learning reconstruction for DWI- and T2w-sequences. Besides the assessment of acquisition times, the main objective of this study was to assess the overall image quality of bpMRI and mpMRI and the influence on PI-RADS scores.
Study Design
- Study Type
- Observational
- Observational Model
- Cohort
- Time Perspective
- Prospective
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- Male
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Elevated PSA >4ng/ml or suspicious digitial rectal exam or supicious transrectal ultrasound
Exclusion Criteria
- •General MRI contraindications (incompatible cardiac pacemaker, neurostimulators) or allergy for gadolinium-containing contrast media or severe claustrophobie
Outcomes
Primary Outcomes
Acquisition time
Time Frame: January - February 2024
Acquisition times for the whole biparametric and whole multiparametric protocol was measured.
Agreement of PI-RADS scores
Time Frame: January - February 2024
Three radiologists with 3, 11 and 12 years of experience in prostate MRI read separately and blinded to personal and clinical parameters (name, age, patient history, value of the prostate specific antigen, clinical examination and transrectal ultrasound) the full bpMRI protocol and graded the lesions according to the PI-RADS classification. Per patient, only the highest graded lesion and its respective prostate zone was noted. If there were two distinct lesions with the highest PI-RADS score in both the peripheral and transitional zone, both were noted. After a washout period of one month all readers did the same for the mpMRI protocol. Both the agreement of biparametric and multiparametric MRI PI-RADS scores for the whole prostate, and for the specific zonal distribution (peripheral and transitional zone) were assessed by calculation of Cohens's κ, interpreted as follows: \<0.5 = poor; 0.5-0.75 = moderate; 0.75-0.9 = good; \>0.9 = excellent.
Image quality
Time Frame: January - February 2024
Two raters with 3 and 11 years of experience rated the bpMRI protocol on a five point Likert scale in six different qualitative categories (artifacts, image sharpness, lesion conspicuity, capsule delineation, overall image sharpness and diagnostic confidence). The grades were defined as follows: 1, non-diagnostic due to extensive artifacts, strongly impaired conspicuity of anatomical structures and no diagnostic confidence; 2, several artifacts, difficult conspicuity of anatomical structures and low diagnostic confidence; 3, moderate artifacts, fair conspicuity of anatomical structures and moderate diagnostic confidence; 4, little artifacts, good conspicuity of anatomical structures and good diagnostic confidence; 5, no artifacts, excellent conspicuity of anatomical structures and high diagnostic confidence. Results of both raters were averaged.
Secondary Outcomes
No secondary outcomes reported
Investigators
Julian Alexander Luetkens
PD Dr. med.; Head of MR-Imaging
University Hospital, Bonn