Fetoscopic Robotic Open Spina bifida Treatment (FROST): feasibility and
learning curve study in a preclinical representative training model
Abstract
Objective: The primary aim was to assess the feasibility of
robotic OSB repair in a preclinical high-fidelity training model,
documenting the learning curve and ensuring quality control among
surgeons. Design: The learning curve was assessed using the
cumulative summation test (LC-CUSUM). Following LC-CUSUM, six additional
experiments were performed for competency-cumulative summation (C-CUSUM)
analysis to ensure ongoing quality control. Setting: The
simulator was created through 3D printing and hand sculpting, simulating
a partially exteriorized uterus for laparotomy-assisted laparoscopic OSB
surgery. It included a silicone uterus, placenta, and fetal manikin with
a simulated OSB lesion, replicating the lesion sac, paraspinal muscles,
and neural placode. Population: Four surgeons participated: an
expert MFM consultant (TVM), a neurosurgical consultant (AK), an MFM
fellow (novice 1, YK), and a neurosurgical resident (novice 2, CK).
Methods: The surgical procedure included 8 steps: uterine
access, working space creation, lesion exposition, junctional zone
dissection, skin mobilization, dural patch application, and closure of
myofascial flaps and skin. Success was defined by precise restoration
(suture interval <3mm), total operative time ≤180 minutes, and a
GEARS score >21/30. Main outcomes: Learning curve
and competency were documented via LC-CUSUM and C-CUSUM.
Results: Competence was achieved after 15–21 procedures, with
novices reaching competency within this range. Participants maintained
high performance in subsequent quality-controlled procedures.
Conclusion: Robotic-assisted fetal OSB surgery in a
high-fidelity simulation is feasible, showing promising outcomes for a
large animal model and clinical translation .