Anatomical Features of Male Rat Urethra and Comparison of Urethral Sphincter Contractility according to Different Urethral Strip Orientations / 대한비뇨기과학회지

PURPOSE: The aim of the study was to clarify the anatomy of the male rat urethra, and to establish a more accurate and consistent method for analyzing external urethral sphincter (EUS) contractility based on this clarified anatomy by comparing different muscle strip orientations. MATERIALS AND METHODS: The whole urethra in male rats was investigated histologically using H/E and immunohistochemical staining. The contractility of the spiral (S) orientation of the entire proximal urethral (EUS) was then compared with the transverse (T) and the ring (R) orientations of the optimal portion, via electrical stimulation in an organ bath. RESULTS: In male rats, the urethral tract consisted of following parts: proximal urethra, transient urethra, urethral diverticula, and penile urethra. Throughout the proximal urethra, a layer of striated muscle fibers encircled the smooth muscle layers. The EUS contraction of the S, TM (Transverse, Middle of proximal urethra) and RM (Ring, Middle of proximal urethra) groups were 4.66+/-0.33mN, 2.92+/-0.33mN and 2.47+/-0.38mN, respectively. The strength of the EUS contraction of the S group was significantly higher than that of the TM. Group, but after adjusting the length, there was no statistically significant difference between the two groups. CONCLUSIONS: Unlike previous studies, showing striated muscle fibers limited to the lower half of the proximal urethra, we noted them throughout the whole proximal urethra. From our results, the spiral orientation of the entire urethra was found to be the optimal configuration for evaluating the contractility of the EUS using fast twitch muscle contractile testing.

Epidermoid Cyst of Testis / 대한비뇨기과학회지

A 24-year-old man visited our hospital with painless scrotal mass 2 weeks in duration. Physical examination revealed about 3cm in diameter, ovoid, hard, movable and painless mass in the left side of the scrotum. He had no history of trauma, voiding difficulty or infection sign. CBC, blood chemistry and tumor marker were normal. Left orchiectomy was done. Tumor was a well encapsulated white-gray ovoid mass filled with yellowish gray material and histogically diagnosed as epidermoid cyst. Benign tumors of testis are rare, acounting for less than 1% of all testicular tumors. Herein we report a case of epidermoid cyst of testis and review the literatures.

Usefulness of Dynamic MRI in Diagnosis of Stress Urinary Incontinence / 대한비뇨기과학회지

PURPOSE: We aimed to define supine static and dynamic magnetic resonance imaging (MRI) appearance of changes in bladder neck and levator ani muscle and find out clinical significance of this method from comparing with valsalva leak point pressure (VLPP) in patients with stress urinary incontinence. MATERIALS AND METHODS: Sixty patients were studied with supine static MR imaging through volumetric axial and sagittal pelvic imaging in the first and second procedures and then were examined with dynamic MR imaging through resting/straining midline sagittal imaging in the third procedure. We evaluated the changes in bladder neck and levator ani muscle of stress urinary incontinence patients from these MR imaging. Patients were divided into two groups according to their responses to VLPP; the group 1 (n=20) with VLPP below 60cmH2O and the group 2 (n=40) with VLPP over 60cmH2O. We analyzed the data taken from comparing MR imaging results with VLPP results. RESULTS: Regarding the degree of changes in bladder neck compared with the results of supine static and dynamic MRI, there were beak shaped changes in the bladder neck in 15 patients from group 1 (75.0%) and especially, in the rest 5 patients excluding 3 patients who had severe cystocele, we could observe 88.2% of beak shaped changes. Beak shaped changes were seen in 5 patients (12.5%) and funnel shaped change or non-specific changes in the rest cases from group 2 (p<0.0001). We could observe the degenerative changes of levator ani muscle in 41 patients from overall (68.3%), which means 13 patients from group 1 (65.0%) and 28 patients from group 2 (70.0%), respectively. CONCLUSIONS: Supine static MRI enables to observe degenerative changes in pelvic floor muscle of stress urinary incontinence while dynamic MRI is deemed to be a relatively comfortable and non-invasive diagnostic method for stress urinary incontinence especially complementing VLLP.