EXPERIMENTAL SUBSTANTIATION OF THE USE OF STROMAL-VASCULAR FRACTION IN AUGMENTATION URETHROPLASTY

In recent years, there has been an increased interest in cell-based technologies, especially multipotent mesenchymal stem cells from the stromal-vascular fraction (SVF) of autologous adipose tissue, because of their regenerative properties. These cells have a unique ability to differentiate and can contribute to the repair of damaged tissues, which makes them promising in the field of surgery and regenerative medicine. In this regard, there is a need to study their use in clinical practice, especially in the context of the treatment of urethral strictures, which can significantly impair the quality of life of patients.

Purpose of the study. To create a model of the urethral stricture in male rabbits of the Chinchilla breed. To evaluate morphological changes occurring in the anastomosis zone during urethroplasty of the oral mucosa with and without the use of SVF obtained from autologous adipose tissue.

Material and methods. At the first stage, urethral stricture was modeled in rabbits and diagnosed by retrograde urethrography after one month time.

At the second stage, the rabbits were divided into two groups: the main group, which underwent oral mucosa augmentation urethroplasty with SVF injection, and the comparison group, which underwent oral mucosa augmentation urethroplasty. Histomorphologic evaluation was performed at 7, 15, 30, and 60 days postoperatively.

Results. Histomorphologic analysis showed that the introduction of SVF in the anastomosis zone promotes a decrease in the severity of inflammation, an increase in the number of vessels and earlier recovery of the urethral mucosal epithelium.

Conclusion. Experimental data confirm that SVF reduces the severity of scarring, activating angiogenesis and providing regenerative and immunomodulatory effects, which allows to apply the results obtained into clinical practice.

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