MRI-DTI Assessment of Urethral Internal Sphincter Ring and Prostate Base Morphology

NCT07694752 | Recruiting

• 1 other identifier: LSKY 2026-048-01
• Study Type: observational
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

This is a single-center, observational imaging study designed to evaluate the in vivo morphology of the male urethral internal sphincter ring using magnetic resonance diffusion tensor imaging (MRI-DTI) fiber tracking and to investigate its relationship with prostate base morphology. Male participants undergoing clinically indicated pelvic, seminal vesicle, or prostate-related MRI-DTI examinations will be included. The study population may include patients with benign prostatic enlargement, younger men undergoing MRI for suspected cryptorchidism or suspected seminal vesiculitis, and patients with prostate cancer scheduled to receive androgen deprivation therapy (ADT). All participants will undergo T2-weighted imaging and DTI. T2WI-DTI image registration, dual-region-of-interest fiber tracking, and three-dimensional reconstruction will be used to visualize ring-like muscle fiber structures in the bladder neck, prostate base, and proximal urethral region. The cross-sectional imaging cohort will be used to assess the associations between prostate-side morphological parameters, including prostate volume, prostate base diameter or area, and intravesical prostatic protrusion, and sphincter-ring parameters, including ring inner diameter and ring area. The ADT paired cohort will undergo MRI-DTI before treatment and during follow-up after ADT to evaluate whether reduction in prostate volume and prostate base morphology is accompanied by corresponding changes in the urethral internal sphincter ring. This study will not alter the participants' existing clinical diagnostic or treatment pathways. Imaging data will be analyzed using standardized post-processing and quantitative measurement procedures. The results may provide in vivo imaging evidence for age- and prostate-related displacement and morphological remodeling of the male urethral internal sphincter and may inform future surgical strategies for identifying, preserving, or reconstructing proximal urinary continence-related structures.

Conditions

Urethral Internal Sphincter Morphology; Benign Prostatic Hyperplasia; Prostate Cancer

Keywords

Diffusion Tensor Imaging; Urethral Internal Sphincter; Prostate Cancer

Outcome Measures

Primary Outcomes (2)

• Urethral Internal Sphincter Ring Inner Diameter Measured by MRI-DTI Fiber Tracking

  The inner diameter of the reconstructed urethral internal sphincter ring will be measured on fused T2-weighted MRI and DTI images. The measurement will be reported in millimeters.

  At baseline MRI for the cross-sectional cohort; at baseline and 3 to 6 months after initiation of ADT for the paired follow-up cohort

• Urethral Internal Sphincter Ring Area Measured by MRI-DTI Fiber Tracking

  The area of the reconstructed urethral internal sphincter ring will be measured on fused T2-weighted MRI and DTI images. The measurement will be reported in square millimeters.

  At baseline MRI for the cross-sectional cohort; at baseline and 3 to 6 months after initiation of ADT for the paired follow-up cohort

Secondary Outcomes (4)

• Prostate Base Diameter Measured on T2-Weighted MRI

  At baseline MRI for the cross-sectional cohort; at baseline and 3 to 6 months after initiation of ADT for the paired follow-up cohort

• Prostate Base Area Measured on T2-Weighted MRI

  At baseline MRI for the cross-sectional cohort; at baseline and 3 to 6 months after initiation of ADT for the paired follow-up cohort

• Intravesical Prostatic Protrusion Measured on Sagittal T2-Weighted MRI

  At baseline MRI for the cross-sectional cohort; at baseline and 3 to 6 months after initiation of ADT for the paired follow-up cohort

• Prostate Volume Calculated From T2-Weighted MRI

  At baseline MRI for the cross-sectional cohort; at baseline and 3 to 6 months after initiation of ADT for the paired follow-up cohort

Other Outcomes (3)

• Change From Baseline in Urethral Internal Sphincter Ring Inner Diameter After ADT

  Baseline and 3 to 6 months after initiation of ADT

• Change From Baseline in Urethral Internal Sphincter Ring Area After ADT

  Baseline and 3 to 6 months after initiation of ADT

• Change From Baseline in Prostate Volume After ADT

  Baseline and 3 to 6 months after initiation of ADT

Study Arms (2)

Cross-sectional MRI-DTI Cohort

Male participants undergoing clinically indicated pelvic, seminal vesicle, or prostate-related MRI-DTI examinations, including younger men and men with prostate enlargement, will be evaluated cross-sectionally to assess the relationship between prostate base morphology and urethral internal sphincter ring morphology.

ADT Paired Follow-up Cohort

Patients with prostate cancer scheduled to receive androgen deprivation therapy will undergo MRI-DTI before treatment and during follow-up after ADT to evaluate whether changes in prostate base morphology are accompanied by corresponding changes in the urethral internal sphincter ring.

Eligibility Criteria

• Age: 15 Years - 90 Years
• Sex: male
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population will consist of male participants undergoing clinically indicated pelvic, seminal vesicle, or prostate-related MRI-DTI examinations at the study center. The cross-sectional imaging cohort will include a broad spectrum of male participants, including younger men undergoing MRI for suspected cryptorchidism or suspected seminal vesiculitis, as well as middle-aged and older men with benign prostatic enlargement or prostate base morphological changes. This cohort will be used to evaluate the relationship between prostate base morphology and urethral internal sphincter ring morphology. A separate paired follow-up cohort will include patients with prostate cancer who are scheduled to receive androgen deprivation therapy. These participants will undergo MRI-DTI before treatment and during follow-up after ADT to assess whether changes in prostate volume and prostate base morphology are accompanied by corresponding changes in the urethral internal sphincter ring.

You may qualify if:

• Male participants undergoing clinically indicated pelvic, seminal vesicle, or prostate-related MRI-DTI examination.
• Participants with adequate T2-weighted MRI and DTI data for post-processing and quantitative assessment of the bladder neck, prostate base, and proximal urethral region.
• Participants in the cross-sectional imaging cohort may include men undergoing MRI for suspected cryptorchidism, suspected seminal vesiculitis, benign prostatic enlargement, or other clinically indicated pelvic or prostate-related evaluations.
• Participants in the ADT paired follow-up cohort must have prostate cancer and be scheduled to receive androgen deprivation therapy, with MRI-DTI planned before treatment and during follow-up after ADT.
• Participants must be able to comply with MRI examination procedures.
• Written informed consent will be obtained when required by the approved study protocol.

You may not qualify if:

• Contraindications to MRI, including but not limited to incompatible metallic implants, severe claustrophobia, or other conditions preventing MRI examination.
• Known neurogenic bladder dysfunction, including spinal cord injury, multiple sclerosis, Parkinson disease, or other neurological disorders that may significantly affect lower urinary tract function.
• History of pelvic radiotherapy.
• History of urethral reconstruction, sphincter surgery, or other prior surgery that substantially alters the bladder neck, proximal urethra, or prostate base anatomy.
• Severe cardiopulmonary dysfunction, cognitive impairment, psychiatric disorder, or other conditions preventing cooperation with MRI examination or study procedures.
• Use of medications or treatments within the previous 3 months that may substantially affect neuromuscular function of the lower urinary tract, as judged by the investigators.
• Poor image quality or failed post-processing that prevents reliable visualization or measurement of the urethral internal sphincter ring.

Sponsors & Collaborators

• Jiangsu Taizhou People's Hospital: lead

Study Sites (1)

JiangsuTaizhouPH

Taizhou, Jiangsu, China

RECRUITING

Related Publications (8)

• Xu Z, Zhao J, Guan Z, Guo M, Bian H, Li Z, Zhao W, Liang S, Liu Y, Zhang S, Wang J. Internal urethral sphincter reconstruction with anterior bladder neck tube for robotic and laparoscopic radical prostatectomy: improving early return of continence. Transl Androl Urol. 2024 Jun 30;13(6):994-1003. doi: 10.21037/tau-23-583. Epub 2024 Jun 26.

  PMID: 38983476 BACKGROUND

• Hotker AM, Mazaheri Y, Zheng J, Moskowitz CS, Berkowitz J, Lantos JE, Pei X, Zelefsky MJ, Hricak H, Akin O. Prostate Cancer: assessing the effects of androgen-deprivation therapy using quantitative diffusion-weighted and dynamic contrast-enhanced MRI. Eur Radiol. 2015 Sep;25(9):2665-72. doi: 10.1007/s00330-015-3688-1. Epub 2015 Mar 29.

  PMID: 25820537 BACKGROUND

• Mason M, Maldonado Pijoan X, Steidle C, Guerif S, Wiegel T, van der Meulen E, Bergqvist PB, Khoo V. Neoadjuvant androgen deprivation therapy for prostate volume reduction, lower urinary tract symptom relief and quality of life improvement in men with intermediate- to high-risk prostate cancer: a randomised non-inferiority trial of degarelix versus goserelin plus bicalutamide. Clin Oncol (R Coll Radiol). 2013 Mar;25(3):190-6. doi: 10.1016/j.clon.2012.09.010. Epub 2012 Dec 17.

  PMID: 23257248 BACKGROUND

• Hikita K, Honda M, Teraoka S, Nishikawa R, Kimura Y, Tsounapi P, Iwamoto H, Morizane S, Takenaka A. Intravesical prostatic protrusion may affect early postoperative continence undergoing robot-assisted radical prostatectomy. BMC Urol. 2020 Oct 21;20(1):164. doi: 10.1186/s12894-020-00740-0.

  PMID: 33087082 BACKGROUND

• Verde ASC, Santinha J, Carrasquinha E, Loucao N, Gaivao A, Fonseca J, Matos C, Papanikolaou N. Diffusion tensor-based fiber tracking of the male urethral sphincter complex in patients undergoing radical prostatectomy: a feasibility study. Insights Imaging. 2020 Nov 27;11(1):126. doi: 10.1186/s13244-020-00927-x.

  PMID: 33245443 BACKGROUND

• Sinha S, Sinha U, Malis V, Bhargava V, Sakamoto K, Rajasekaran M. Exploration of male urethral sphincter complex using diffusion tensor imaging (DTI)-based fiber-tracking. J Magn Reson Imaging. 2018 Oct;48(4):1002-1011. doi: 10.1002/jmri.26017. Epub 2018 Mar 23.

  PMID: 29573022 BACKGROUND

• Koraitim MM. The male urethral sphincter complex revisited: an anatomical concept and its physiological correlate. J Urol. 2008 May;179(5):1683-9. doi: 10.1016/j.juro.2008.01.010. Epub 2008 Mar 17.

  PMID: 18343449 BACKGROUND

• Kim JW, Kim DK, Ahn HK, Jung HD, Lee JY, Cho KS. Effect of Bladder Neck Preservation on Long-Term Urinary Continence after Robot-Assisted Laparoscopic Prostatectomy: A Systematic Review and Meta-Analysis. J Clin Med. 2019 Nov 24;8(12):2068. doi: 10.3390/jcm8122068.

  PMID: 31771310 BACKGROUND

MeSH Terms

Conditions

Prostatic Hyperplasia; Prostatic Neoplasms

Condition Hierarchy (Ancestors)

Prostatic Diseases; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Male Urogenital Diseases; Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 6, 2026
• First Posted: July 10, 2026
• Study Start: July 15, 2026
• Primary Completion (Estimated): August 1, 2027
• Study Completion (Estimated): June 1, 2028
• Last Updated: July 20, 2026

Record last verified: 2026-07

Locations

CN (1)