1 Department of Surgery, Erasmus MC-University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands. m.verstegen@erasmusmc.nl.
2 Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, 3584 CT Utrecht, The Netherlands. B.Spee@uu.nl.
3 Department of Surgery, Erasmus MC-University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands. l.vanderlaan@erasmusmc.nl.