TY - JOUR
T1 - Validation of an ovine vesicovaginal fistula model
AU - Maljaars, Lennart P.
AU - Jeffery, Stephen T.
AU - Scholten, Marlou
AU - Kaestner, Lisa
AU - Jere, Khumbo
AU - Bezuidenhout, Deon
AU - Guler, Zeliha
AU - Roovers, Jan-Paul W. R.
N1 - Funding Information: We thank the veterinarian Dr. Friso Woudstra and the staff of the Mariendahl Experimental Farm, Stellenbosch, South Africa, for the excellent caretaking of the animals. We would like to thank Helen Ilsley for preparing the histology samples. Last, we would like to express our gratitude to Stichting Wetenschappelijk Onderzoek Assistenten Heelkundige Specialismen (SWOAHS) and the Collegium Chirurgicum Neerlandicum (CNN) for their support through the Prof. dr. P.J. Klopper award for experimental research. Publisher Copyright: © 2022, The Author(s).
PY - 2022/11
Y1 - 2022/11
N2 - Introduction and hypothesis: A representative, large animal model of vesicovaginal fistulas is needed for the training of surgeons and for the development of new surgical techniques and materials for obstetric fistula repair. Methods: The safety, feasibility, and reproducibility of vesicovaginal fistula creation were studied in 4 adult female sheep. A 1-cm fistula was created between the vagina and the bladder through a transvaginal approach. The defect was allowed to heal for 8 weeks and the animals were then euthanized. The primary outcome was the fistula patency. Secondary outcomes were fistula size, urogenital dimensions, urodynamic evaluation, histology (inflammation, vascularization, collagen deposition) and biomechanical characteristics of the fistula edge (stress at break, maximum elongation, and stiffness). Results: The transvaginal creation of a vesicovaginal fistula was safe. All animals survived the surgical procedure and follow-up period, without complications. Three of the four animals demonstrated a patent vesicovaginal fistula after 8 weeks. Baseline data are provided of the urogenital dimensions and the urodynamic, histological, and biomechanical characteristics of the model. Conclusions: The ewe is a safe, feasible, and reproducible model for vesicovaginal fistulas. The model can help to study new techniques and materials to boost surgical innovation for vesicovaginal fistula repair.
AB - Introduction and hypothesis: A representative, large animal model of vesicovaginal fistulas is needed for the training of surgeons and for the development of new surgical techniques and materials for obstetric fistula repair. Methods: The safety, feasibility, and reproducibility of vesicovaginal fistula creation were studied in 4 adult female sheep. A 1-cm fistula was created between the vagina and the bladder through a transvaginal approach. The defect was allowed to heal for 8 weeks and the animals were then euthanized. The primary outcome was the fistula patency. Secondary outcomes were fistula size, urogenital dimensions, urodynamic evaluation, histology (inflammation, vascularization, collagen deposition) and biomechanical characteristics of the fistula edge (stress at break, maximum elongation, and stiffness). Results: The transvaginal creation of a vesicovaginal fistula was safe. All animals survived the surgical procedure and follow-up period, without complications. Three of the four animals demonstrated a patent vesicovaginal fistula after 8 weeks. Baseline data are provided of the urogenital dimensions and the urodynamic, histological, and biomechanical characteristics of the model. Conclusions: The ewe is a safe, feasible, and reproducible model for vesicovaginal fistulas. The model can help to study new techniques and materials to boost surgical innovation for vesicovaginal fistula repair.
KW - Biomechanics
KW - Histology
KW - Large animal model
KW - Surgical technique
KW - Transvaginal approach
KW - Vesicovaginal fistula
UR - http://www.scopus.com/inward/record.url?scp=85138224733&partnerID=8YFLogxK
U2 - https://doi.org/10.1007/s00192-022-05342-y
DO - https://doi.org/10.1007/s00192-022-05342-y
M3 - Article
C2 - 36121458
SN - 0937-3462
VL - 33
SP - 3185
EP - 3193
JO - International urogynecology journal and pelvic floor dysfunction
JF - International urogynecology journal and pelvic floor dysfunction
IS - 11
ER -