Three-Dimensionally-Printed Kidney Models for Living Donor and Recipient Transplant Education: A Pilot Study

Technical Summary: Three-Dimensionally-Printed Kidney Models for Living Donor and Recipient Transplant Education

Problem Statement
Living donor kidney transplantation (LDKT) remains underutilized despite offering timely, cost-effective treatment compared to deceased donation. A primary barrier to adoption is the complexity of the consent process and challenges in effectively educating potential donors and recipients. Candidates often lack sufficient knowledge regarding procedures and risks, which can diminish willingness to donate. While three-dimensional (3D) printed models have demonstrated utility in other surgical fields for reducing preoperative anxiety and improving treatment satisfaction, their specific application for educating both living donors and recipients in the context of LDKT has remained largely unexplored. There is a recognized need for standardized, patient-specific, and interactive educational tools to bridge the gap between abstract surgical concepts and patient understanding.

Methodology
This single-center pilot study, conducted at Michigan Medicine between July 2023 and March 2024, evaluated the feasibility and impact of personalized 3D-printed kidney models in LDKT education.

• Participants: The cohort consisted of 10 participants (5 living donors and 5 recipients) scheduled for LDKT. Participation was voluntary, and the study was exempted by the institutional review board.
• Model Generation: Anonymized multiphase CT renal donor protocol scans (DICOM files with 0.625 mm slices) were processed using Materialise Mimics Software (v26.0) to create patient-specific 3D representations of the kidney, including unilateral parenchyma, vasculature, and ureter. The models were converted to .STL format, smoothed, and had internal cavities removed using Meshmixer. Vessel diameters were moderately enlarged to facilitate printing.
• Fabrication: Models were printed using polylactic acid (PLA) on a desktop Prusa i3 MK3S+ printer. The process required approximately 2 hours of electronic processing and 8 hours of printing time per model, with a material cost of approximately $1.90 per unit.
• Intervention: Participants underwent a 15-minute standardized educational session led by the research team, incorporating their specific 3D-printed kidney model. The session covered patient-specific anatomy, surgical steps, risks, and potential complications.
• Data Collection: Participants completed pre- and post-intervention surveys. These included questions adapted from the Amsterdam Preoperative Anxiety and Information Scale (APAIS) to assess understanding and the Visual Analog Scale for Anxiety (VAS-A) to measure anxiety levels (0–10). Statistical analysis utilized Chi-square tests for Likert scale data and Wilcoxon signed-rank tests for anxiety scores.

Key Results

• Educational Impact: Post-intervention analysis revealed statistically significant improvements in self-reported understanding. Participants showed increased agreement with the statements "I have a good understanding of the transplant procedure" (p = 0.037) and "I could explain the main steps of the surgical procedure to someone else" (p = 0.011).
• Perception of Utility: 100% of participants agreed that the 3D model improved their understanding of the procedure, risks, and anatomy. Furthermore, 80% reported that the model made them feel more secure about the upcoming surgery.
• Anxiety Levels: While anxiety scores (VAS-A) showed an average numerical decrease following the education session, this reduction was not statistically significant (p = 0.250). Five participants reported no change in anxiety levels.
• Feasibility: The study demonstrated that patient-specific models could be generated rapidly (within 8 hours of printing) at a low cost (~$1.90), making the approach scalable for clinical settings.

Significance and Claims
The paper posits that patient-specific 3D-printed kidney models represent a reproducible, low-cost, and time-efficient method to enhance preoperative education for living donor kidney transplantation. The authors claim that these models successfully translate abstract surgical concepts into tangible, concrete forms, thereby addressing a key educational barrier in the LDKT evaluation process.

The study highlights that while the primary outcome was a significant improvement in procedural understanding, the models also fostered a sense of security among participants. The authors suggest that integrating these models into transplant counseling can support shared decision-making and potentially aid in donor engagement by allowing candidates to better visualize the procedure and educate their social support networks.

The paper maintains a modest tone regarding its conclusions, acknowledging limitations such as the small sample size (n=10), single-center design, and reliance on self-reported outcomes. It explicitly states that the study does not claim to have proven an increase in actual donation rates, noting that further research with larger, multicenter cohorts is required to assess knowledge retention, decision quality, and downstream behavioral impacts. The authors conclude that 3D models serve as an important educational adjunct that merits evaluation in larger, controlled studies.