[Reconstructive urology in transition. From its origin into the all too near future]

Biofabrication and biomaterials for urinary tract reconstruction

Reconstructive urologists are constantly facing diverse and complex pathologies that require structural and functional restoration of urinary organs. There is always a demand for a biocompatible material to repair or substitute the urinary tract instead of using patient's autologous tissues with its associated morbidity. Biomimetic approaches are tissue-engineering tactics aiming to tailor the material physical and biological properties to behave physiologically similar to the urinary system. This review highlights the different strategies to mimic urinary tissues including modifications in structure, surface chemistry, and cellular response of a range of biological and synthetic materials. The article also outlines the measures to minimize infectious complications, which might lead to graft failure. Relevant experimental and preclinical studies are discussed, as well as promising biomimetic approaches such as three-dimensional bioprinting.

Outcome of buccal mucosa and lingual mucosa graft urethroplasty in the management of urethral strictures: A comparative study

Objective:

The objective of the study was to compare the outcome of buccal and lingual mucosa graft (LMG) augmentation urethroplasty along with donor sites morbidities in anterior urethra stricture.

Subjects and Methods:

From September 2010 to January 2014, 125 patients underwent single stage augmentation urethroplasty. They were randomly divided into two groups to receive either buccal mucosa graft (BMG) or LMG. The patients were prospectively followed for complications and outcome.

Results:

Baseline characteristics such as mean age, etiology, stricture length, and location were comparable in both groups. Overall success rate for Group 1 and Group 2 were 69.2% and 80%, respectively. Mean follow-up periods were 28.2 and 25 months in Group 1 and Group 2, respectively.

Conclusions:

LMG provides the better outcome with fewer immediate and delayed complications as compared to BMG. The length of stricture and width of graft were main factors affecting the outcome.

[Bioartificial urothelium generated from bladder washings. A future therapeutic option for reconstructive surgery]

Reconstructive surgery of lower urinary tract disorders can be limited by a shortage of adequate autologous tissue. Tissue engineering is an option for surgical reconstruction with evolved biological substitutes. Urethral repair with bioartificial urothelial implants can be an innovative method for sustained urothelial regeneration in situ. The needed urothelial cells are commonly isolated from native urothelium requiring surgery.The aim of this study was to establish primary human urothelial cell cultures from bladder washings in serum-free media and to generate urothelial tissue without seeding of matrices in a feeder cell-free system. It could be demonstrated that under these conditions bioartificial urothelium can be developed successfully from bladder washings. Its multilayered cellular structure and the initial differentiation in vitro, similar to native-grown urothelial tissue, are promising with regard to intended clinical application. Current work focuses on establishing cell culture techniques according to legal regulations, terminal differentiation of the urothelial constructs in vitro, and techniques to surgically implant lab-grown bioartificial urothelium.