478
A unique ex vivo porcine model was created by Zhang et al. in 2008 by wrapping
a porcine kidney in a full-thickness skin flap complete with fascia and muscle
(Fig. 24.13) [ 165 ]. Trainees using this model found it to be quite useful; however,
the authors note that the 12th rib is an important anatomical landmark for percutane-
ous renal access. Therefore, they modified their model to incorporate a portion of
porcine thoracic or abdominal wall that contained at least two ribs [ 166 ]. One hun-
dred twenty-six urologists tried the modified model, and 90.5% rated the model as
“helpful” or “very helpful” for simulation of PCNL.
Currently, there is a single validated PCNL bench model as described by Zhang
et al. [ 167 ]. The model is 36 × 32 × 12 cm and composed of three components made
of mixed silicon materials (Fig. 24.14). Consisting of a kidney with a dilated col-
lecting system with an attached ureteral stump, the model is encased within simu-
lated perirenal tissue of approximately 4 cm thickness. The goal of this model was
to simulate the texture of the human body as much as possible. Similar to previous
bench models, trainees can practice both fluoroscopy and ultrasound techniques on
this model to obtain renal access. A significant advantage of this model was that
multiple trainees could repeatedly use it as it is tolerant to multiple sticks for needle
access; however, the cost-effectiveness of this model versus ex vivo animal models
has never been studied. In their study, Zhang et al. demonstrated face, content, and
construct validity for the model. Nine experts—considered experts as they’ve
logged over 60 cases—and thirty novices were enrolled in the study and performed
fluoroscopy-guided percutaneous renal access on the model. The experts rated the
model an overall appraisal of 4 out of 5 points on a 1–5-point Likert scale, a score
of 5 for utility as a training tool, and a score of 4 as an assessment tool, thus giving
the model both face and content validity. Significant differences were found between
Fig. 24.14 UroEmerge™ Suprapubic Catheter Model contains an abdominal pad that simulates
skin and rectus sheath [ 6 ]
W. Baas et al.