MRI of the urethra in women with lower urinary tract symptoms: spectrum of findings at static and dynamic imaging

Abstract

Objective: The purpose of our study was to determine the findings at both static and dynamic MRI in women with a clinically suspected urethral abnormality.

Materials and methods: MRI of the urethra was performed in 84 women with lower urinary tract symptoms using multiplanar T2-weighted turbo spin-echo and unenhanced and contrast-enhanced gradient-echo sequences. A dynamic true fast imaging with steady-state free precession sequence was performed during straining in the sagittal plane. Images were evaluated by two radiologists for urethral pathology and pelvic organ prolapse. MRI findings were correlated with clinical symptoms using the Fisher's exact and Mann-Whitney tests.

Results: Urethral abnormalities were found in 10 of 84 patients (11.9%), including two urethral diverticula, five Skene's gland cysts or abscesses, and three periurethral cysts. Thirty-three patients (39.3%) were diagnosed with pelvic organ prolapse, of whom 29 (87.9%) were diagnosed exclusively on dynamic imaging. In 29 of 33 patients with prolapse (87.9%), the urethra was structurally normal. MRI showed 13 cystoceles and 17 cases of urethral hypermobility not detected on physical examination. Patients with a greater number of vaginal deliveries, stress urinary incontinence, frequency of voiding, and voiding difficulty were statistically more likely to have anterior compartment prolapse (p < 0.05).

Conclusion: Including a dynamic sequence permits both structural and functional evaluation of the urethra, which may be of added value in women with lower urinary tract symptoms. Dynamic MRI allows detection of pelvic organ prolapse that may not be evident on conventional static sequences.