A Novel Technique for the Three-Dimensional Visualization of Tissue Defects Using Tissue Paper Models: Spatial Analysis for Reconstruction Assessment Method

Abstract

Background

This technical note presents an innovative technique that uses tissue paper to create three-dimensional (3D) models to visualize tissue defects. This approach allows the construction of detailed, anatomically accurate models that significantly enhance surgeons' and medical professionals' comprehension of tissue damage in various clinical scenarios.

Methods

The key aspects of this technique include assessing the location and size of the defect, selecting an appropriate donor site, and designing the flap using tissue paper at the recipient site before refining it to match the donor site. Different flap designs, such as local, regional, and free flaps, are used, each offering distinct advantages and limitations depending on the clinical context.

Results

This technique is straightforward, cost-effective, and highly adaptable, making it an invaluable tool for both preoperative planning and educational purposes. Meticulous attention to detail is essential for flap design because it directly influences the success of the procedure. Critical factors, such as tissue laxity, scar orientation, and aesthetic subunits, must be carefully considered to ensure optimal wound healing and cosmetic outcomes.

Conclusion

In summary, the use of tissue paper to create 3D models is a valuable technique that enhances the understanding and planning of surgical interventions for tissue defects, ultimately improving clinical outcomes.

Keywords

flap design - reconstruction assessment - tissue defect - flap surgery - sterile tissue paper

Flap design is a cornerstone of modern reconstructive surgery, with its origins tracing back to around 1000 to 800 BC when Sushruta, a pioneer in surgical techniques in Samahita, India, first described the use of a regional pedicle flap for nasal reconstruction. This marked the beginning of flap surgery as a key method for tissue restoration.[1] Over time, surgical advancements and a deeper understanding of human anatomy and physiology have led to significant improvements in flap application. Currently, flaps are widely used to reconstruct tissue defects resulting from trauma, oncologic resection, congenital anomalies, and chronic wounds.

A deep understanding of the anatomy and physiology of both the defect and potential donor sites is essential for the success of flap transfer, along with mastery of atraumatic soft tissue surgical techniques.[2] The key principle of this procedure is the precise “replacement of like with like,” which involves the strategic creation and transfer of tissue flaps to restore both form and function in areas affected by tissue loss.[3] The practice of flap design and transfer combines medical science with surgical artistry, often determining whether the procedure yields highly successful results.

The choice of flap type depends on factors such as the defect's location and size, availability of adjacent tissue, and required vascularization.[4] Flaps offer a significant advantage in addressing complex defects owing to their versatility in design and ability to incorporate different tissue types. This approach allows personalized reconstruction based on patient needs. The selection of the appropriate flap requires thorough patient evaluation and careful planning. An incorrect choice can lead to complications, such as tissue necrosis, due to inadequate blood supply to the recipient site.[5]

Furthermore, flap procedures require specialized skills, particularly in microsurgery, when dealing with free flaps. Continuous research and technical advancements are critical for reconstructive surgery. Three-dimensional (3D) visualization of tissue defects is crucial for surgical planning and medical education. Although advanced techniques, such as imaging and digital modeling, have improved the precision of tissue assessment and preoperative planning, they are expensive and may lack the tactile feedback essential for some applications.[6] [7] [8] [9] [10] [11] [12]

This technical note introduces an innovative approach that uses sterile tissue paper to construct 3D models of tissue defects. This method offers an accessible, cost-effective, and efficient solution for enhancing the understanding of anatomical structures and the extent of tissue damage, providing valuable support in both clinical and educational settings.

Methods

The materials used were carefully selected to ensure precision and sterility during the flap design process. Sterile tissue paper was chosen for its flexibility and ease of manipulation, making it ideal for creating accurate 3D models of the flap. A total of nine steps explaining three main processes, involving designing the flap and its pedicle, trimming the model, and placing it on the defect, were carried out ([Fig. 1]).

Fig. 1 Step-by-step creation of a 3D tissue paper model for defect measurement in flap surgery visualization. ALT, anterolateral thigh; 3D, three-dimensional.

A sterile surgical marker was used to trace and mark the tissue paper, allowing precise delineation of the defect and flap design. Surgical scissors provided the necessary precision to cut the tissue paper according to the marked outlines, thereby ensuring that the model accurately reflected the intended flap dimensions (see [Supplementary Video 1]). A 3D model was created for a patient undergoing hand contracture release, where the defect was reconstructed using an anterolateral thigh (ALT) flap. The tissue paper model was carefully contoured to the required dimensions, incorporating a multiple Z-plasty design to ensure precise flap placement and optimal adaptation to the defect site. Anatomical references play a crucial role in guiding the replication of anatomical structures, ensuring that the tissue paper model closely mirrors the actual surgical requirements, and aiding in planning an effective and aesthetically pleasing flap design.

Video 1 The video demonstrates a novel technique utilizing tissue paper to create three-dimensional (3D) models for visualizing tissue defects and planning flap reconstruction surgery. The step-by-step process covers defect assessment, flap design, and model trimming, highlighting the technique's effectiveness in preoperative planning and surgical education.

Step 1: Preparation of the Recipient Site

The recipient site was first prepared by cleaning and draping the area in a sterile manner to ensure that the surrounding tissue was clearly visible and accessible for flap design. The dimensions of the tissue defects were carefully measured and recorded, including details such as defect depth, width, and any associated anatomical landmarks.

Step 2: Design of the Flap on Sterile Tissue Paper

A sheet of sterile tissue paper was placed over the recipient site. Using a sterile surgical marker, the outline of the defect was traced directly onto tissue paper. Additional anatomical landmarks were marked as needed to assist with flap orientation and design. Tissue paper was used to design the proposed flap. The design considered factors such as the size and location of the defect, tissue laxity, scar orientation, and desired cosmetic outcome. The flap was outlined on tissue paper, and any necessary adjustments were made to ensure that the tissue could be effectively mobilized, rotated, or transposed to cover the defect. The flap was carefully removed from the tissue paper using sterile surgical scissors.

Step 3: Adjusting the Tissue Paper Design to the Donor Site

The cut tissue paper model was placed over the recipient site to assess its fit and make any necessary adjustments. The model was refined to accurately represent the final design of the flap.

Step 4: Application of the Tissue Paper Model Flap to the Recipient Site

The tissue paper flap model was temporarily secured to the recipient site using sterile adhesive tape. The model was then evaluated for its ability to adequately cover the defect while maintaining a proper vascular supply and preserving the aesthetics of the surrounding tissue. Adjustments were made as necessary to optimize the flap design.

Step 5: Final Assessment and Documentation

After the final adjustments, the tissue paper model was removed, and the design was documented through photographs and detailed notes. The model provided a 3D representation of the proposed flap, providing valuable insights into the feasibility and expected outcomes of surgery. This method was repeated for each patient, with the tissue paper model serving as the guide during flap surgery. The sterile tissue paper technique is a simple, cost-effective, and highly adaptable approach for flap design, contributing to improved surgical planning and outcomes.

Ethical Approval Statement

This study was conducted in accordance with the ethical standards outlined in the Declaration of Helsinki. Ethical approval for this research, involving three participants, was obtained from the Fatmawati General Hospital Jakarta Ethic Committee-approved protocol, and all participants provided informed consent before their participation. Confidentiality and anonymity were maintained throughout the study, and participants were informed of their right to withdraw from the study at any time without any consequences.

Informed Consent Statement

This research study involves the participation of human subjects. We would like to inform all stakeholders that informed consent was obtained from the participants prior to their involvement in the study. Three participants have voluntarily agreed to take part in this research and have provided written consent after being fully informed of the study's objectives, procedures, potential risks, and benefits. The participants were assured that their participation was voluntary, and they had the right to withdraw from the study at any time without any penalty. The confidentiality of all personal data collected during this research will be maintained, and the results will be anonymized to protect their identities. We confirm that all ethical standards for research involving human subjects have been followed, and the consent obtained adheres to relevant institutional guidelines and regulations.

Results

Preliminary applications of this technique have demonstrated its utility in the visualization of complex tissue defects. Surgeons have successfully used tissue paper models for preoperative planning to better understand the spatial relationships between structures. Additionally, the models are effective educational tools for teaching medical students and residents. The Spatial Analysis for Reconstruction Assessment (SARA) method is regularly performed for free flap surgery in Fatmawati General Hospital, Jakarta, by the authors, and has already been applied in more than 50 patients since 2022.

In this study, we presented only three patients who underwent defect reconstruction with ALT free flap with complete intraoperative documentation. The first patient was a 60-year-old male with squamous cell carcinoma excised from the left side of the face ([Fig. 2]). The second patient shown here is a 35-year-old female with an irregular shape defect after burn contracture excision (multiple W-plasty design) on lower right arm and reconstructed with an ALT Flap ([Fig. 3]). The third patient was a 59-year-old man who had a sarcoma on his chest for 2 years. Intraoperatively, the defect after tumor resection was circular with a diameter of 12.6 cm ([Fig. 4]).

Fig. 2 (A) Defect after tumor removal. (B) Precisely trimmed 3D tissue paper model aligned with the anatomical contours of the defect. (C) The anterolateral thigh is dissected, showing the vastus lateralis and rectus femoris with the lateral circumflex femoral artery (LCFA) perforator spared. (D) The 3D model was positioned on the donor site, and the specific shape was accurately delineated. (E) The ALT flap is harvested according to the shape of the 3D model, including the vascular pedicle. (F). The flap is inserted into the facial defect, and anastomoses connect the perforator and its pedicle. 3D, three-dimensional.

Fig. 3 (A) Irregular shape of burn contracture on the lower right arm. (B) Tissue paper model with blood seepage to create the precision shape of the defect after excision. (C) Precisely trimmed 3D tissue paper model aligned with the anatomical contours of the defect. (D) The tissue paper model was placed on the ALT flap. (E) ALT flap was harvested according to the shape of the 3D model, including the vascular pedicle. (F). The flap was inserted into the facial defect, and anastomoses were created to connect the vascular pedicle to the recipient vessels to ensure adequate perfusion. ALT, anterolateral thigh; 3D, three-dimensional.

Fig. 4 (A) Defect after tumor removal. (B) Precisely trimmed 3D tissue paper model aligned with the anatomical contours of the defect. (C) The ALT flap is harvested and divided into two parts to fit the shape of the 3D model, including the vascular pedicle from the LCFA. (D) The flap is inserted into the chest defect with anastomoses connecting the perforator and its pedicle. LCFA, lateral circumflex femoral artery; 3D, three-dimensional.

Discussion

The use of tissue paper to create 3D models of tissue defects offers several advantages. It is an inexpensive and accessible method that can be easily integrated into clinical practice and education. The tactile nature of these models provides a unique advantage over digital or purely visual methods, allowing users to physically manipulate and explore their structures. However, this technique has limitations, including the potential for less precise details compared to advanced imaging or 3D printing. Despite these limitations, the proposed method serves as a valuable complementary tool in both educational and clinical settings.

The use of tissue paper to create 3D models for defect measurement in flap surgery offers substantial advantages that outweigh its inherent limitations. This method is highly cost-effective and widely accessible, rendering it a practical tool for both clinical applications and educational settings. The material's flexibility and thin profile facilitate precise manipulation, allowing for accurate contouring to replicate the anatomical dimensions of the defect. Moreover, the tactile feedback provided by the physical model enhances the learning experience, offering hands-on interaction that surpasses the capabilities of digital simulations. The simplicity and efficiency of designing and shaping the tissue paper model enable rapid prototyping of various flap designs, while the model itself serves as an effective visual aid. This enhances the understanding of spatial relationships between the defect and surrounding tissues, making it particularly valuable for educational purposes and surgical training in flap design and tissue manipulation.

Although the tissue paper model used in our study features a thin texture, this characteristic imparts flexibility, allowing surgeons to modify the model easily. Previous modalities for free flap planning, such as 3D-printed models, have limitations in accounting for flap thickness. Similarly, in the SARA method, the tissue paper model does not inherently account for flap thickness. To address this limitation, we routinely estimate flap thickness during our procedures. We typically perform primary thinning down to the Scarpa fascia, leaving a 3-cm cuff of deep fat around the perforator. In cases where tension persists, leaving 1 to 2 cm of the flap unsutured at the anastomosis site can be beneficial. This approach allows for edema to resolve, facilitating a tension-free secondary closure, which can typically be performed in a standard clinical setting after approximately 2 weeks.

Despite certain limitations, such as the fragility of tissue paper and the absence of feedback on critical parameters like vascular supply and tissue elasticity, these drawbacks are generally manageable. The ease of use, combined with the enhanced visual and spatial understanding provided by the models, makes this technique particularly advantageous for preoperative planning and educational applications. While additional care may be required to maintain sterility in surgical environments and precise scaling for smaller or more complex defects can present challenges, these factors do not undermine the overall utility of the method. Although the tissue paper models do not fully replicate the texture or biomechanical properties of actual tissues, the method's affordability, speed, and educational value establish it as a highly effective tool for surgical planning and training in reconstructive procedures. Further research is needed to refine the technique, address its limitations, and improve its precision. Incorporating more accurate representations of tissue properties and developing models that simulate real-time surgical conditions could greatly enhance its utility, transforming it into an even more effective tool for preoperative planning, training, and education in the medical field.

Conclusion

The SARA method of using tissue paper models for the 3D visualization of tissue defects demonstrates considerable potential as a practical, cost-effective tool for enhancing anatomical understanding and facilitating surgical planning. Its versatility and adaptability make it especially valuable in both clinical and educational settings.

Conflict of Interest

None declared.

Acknowledgments

The authors would like to express their sincere gratitude to all individuals who contributed to the successful completion of this research. We also acknowledge the guidance of our mentors and colleagues, whose expertise greatly enhanced the quality of our work. Additionally, we declare that this study did not receive any external financial support or funding from any sources.

Authors' Contributions

The first author (S.E.T.) conceptualized the innovative approach presented in this technical note and served as the primary operator for the surgical procedures performed. In addition to leading the development and execution of the technique, she also played a major role in drafting the manuscript. As the second operator (E.S.S.), supporting the technical execution of surgeries. She also assisted in refining the manuscript by conducting critical grammar and punctuation reviews and ensuring compliance with plagiarism standards. The procedure was documented comprehensively by one of the study authors (J.P.S.), who also contributed extensively to writing and editing the manuscript, and designed the accompanying illustrations to enhance the clarity of the novel technique described.

Disclosure

All authors report no relationships that could be construed as a conflict of interest. All authors take responsibility for all aspects of the reliability and freedom from bias of the data presented and their discussed interpretation.

• References

• 1 Fang F, Chung KC. An evolutionary perspective on the history of flap reconstruction in the upper extremity. Hand Clin 2014; 30 (02) 109-122
• 2 Saber AY, Hohman MH, Dreyer MA. Basic Flap Design. In: StatPearls. Treasure Island, FL: StatPearls Publishing; 2024
• 3 Sloan GM, Reinisch JF. Flap physiology and the prediction of flap viability. Hand Clin 1985; 1 (04) 609-619
• 4 Mendoza Sánchez PA, Montaño Vasquez FA, Cruz López MA. et al. An analysis of flaps in reconstructive surgery. Int J Med Sci Clin Res Stud. 2024; 4 (06) 1282-1285
• 5 Martinez Bravo VM, Dominguez Gutierrez CJ, Hazouri Venegas S, Tognola Sánchez MF. Literature review of flaps in reconstructive surgery: Definition, indications, complications and management. Int J Med Sci Clin Res Stud. 2023; 3 (06) 1169-1171
• 6 Fletcher J, Miskovic D. Digital and 3D Printed Models for Surgical Planning. In: Atallah S. ed. Digital Surgery. Cham: Springer; 2021
• 7 Powell AR, Srinivasan S, Green G, Kim J, Zopf DA. Computer-aided design, 3-D-printed manufacturing, and expert validation of a high-fidelity facial flap surgical simulator. JAMA Facial Plast Surg 2019; 21 (04) 327-331
• 8 Lerner JL, Vishwanath N, Borrelli MR, Rao V, Crozier J, Woo ASA. A cost-effective, three-dimensionally printed simulation model facilitates learning of bilobed and banner flaps for mohs nasal reconstruction: A pilot study. Plast Reconstr Surg 2024; 154 (02) 358e-361e
• 9 Nicolaou M, Yang GZ, Darzi A, Butler PE. An inexpensive 3-D model for teaching local flap design on the face and head. Ann R Coll Surg Engl 2006; 88 (03) 320
• 10 Mattox AR, Behshad R, Sepe DJ, Armbrecht ES, Maher IA. Three-dimensional modeling and comparison of nasal flap designs. Arch Dermatol Res 2020; 312 (08) 575-579
• 11 Ganry L, Quilichini J, Bandini CM, Leyder P, Hersant B, Meningaud JP. Three-dimensional surgical modelling with an open-source software protocol: study of precision and reproducibility in mandibular reconstruction with the fibula free flap. Int J Oral Maxillofac Implants 2017; 46 (08) 946-957
• 12 Reilly FOF, Dimovska EOF, Lindell B, Thor A, Rodriguez-Lorenzo A. Tips to virtually plan your free scapula flap. Plast Reconstr Surg Glob Open 2024; 12 (09) e6189

Publikationsverlauf

Eingereicht: 23. November 2024

Angenommen: 17. April 2025

Artikel online veröffentlicht:
21. Mai 2025