Is there a Difference in Platelet-Rich Plasma Application Method and Frequency to Protect Against Urethral Stricture?

To determine the efficacy of instillation frequency and submucosal injection of platelet-rich plasma (PRP) after urethral trauma to prevent urethral inflammation and spongiofibrosis.

Sixty-five rats were used in the study; 50 rats were randomized into 5 groups with 10 rats in each group and 15 rats were allocated for PRP preparation. The urethras of all rats were traumatized with a pediatric urethrotome knife at 6 and 12 o’clock positions, except in the sham group. Group 1 was the sham group and had only urethral catheterization daily for 15 days, Group 2 was given 0.9% saline (physiologic saline [(UI+PS]) once a day after urethral injury (UI+ PS), Group 3 was injected with PRP submucosally after urethral injury, Group 4 was given PRP once a day as intraurethral instillation using a 22 Ga catheter sheath with urethral injury, and Group 5 was given PRP twice a day as intraurethral instillation using a 22 Ga catheter sheath with urethral injury. Each administration of PRP was administered as 300 million platelets/150 microliters. On day 15, the penises of the rats were degloved to perform penectomy. Histopathologic evaluation was made for spongiofibrosis, inflam - mation, and congestion in vascular structures.

When the sham group, UI+PS, UI+PRPx1, UI+PRPx2 and UI+PRPs groups are compared in total, there were significant differences identified for parameters other than edema. When the UI+PS, UI+PRPx1, UI+PRPx2 and UI+PRPs groups are compared, the UI+PS group was observed to have significantly more inflammation (mu - cosal inf. 2.42 ± 0.53) and spongiofibrosis (2.42 ± 0.53). All the PRP groups were identified to have significantly less mucosal inflammation (UI+PRPs 1 ± 0, UI + PRPx1; 1.4 ± 0.51, PRPx2; 1.33 ± 0.5) and spongiofibrosis (UI+PRPs; 1.57 ± 0.53, PRPx1; 1.2 ± 0.42, PRPx2; 1.55 ± 0.52). The group with the lowest spongiofibrosis was the PRPx1 group.

This study showed that PRP significantly reduced mucosal inflammation and spongiofibrosis, inde - pendent of the administration route, when applied to the urethra after urethral trauma.