Virtual Surgical Planning for Gender-Affirming Facial Surgery

Publication date: 4/30/2024

Introduction

Gender-affirming facial surgery plays a pivotal role in helping transgender and non-binary individuals align their physical appearance with their gender identity. Facial features are central to one’s sense of self and identity, and surgical interventions can provide a profound sense of congruence and relief. As technology continues to evolve, virtual surgical planning (VSP) has emerged as a transformative tool in the realm of gender-affirming facial surgery. This article explores the applications of VSP in facial feminization and masculinization surgery, highlighting the areas where it is potentially beneficial.

Facial gender-affirming surgery encompasses a range of procedures aimed at reshaping the facial structures to create more feminine or masculine appearances, depending on the patient’s goals. The procedures may include modifications to the forehead, brow, nose, jawline, chin, and soft tissues. Each surgery is tailored to address the unique needs and aesthetic goals of the individual, emphasizing the importance of personalized treatment plans. VSP serves a role in some, but not all, of these procedures.

Gender-affirming facial surgery presents unique challenges due to the difficulty of accessing all the bony areas of the face and modifying the bone within small access points where visibility can often be quite poor. Traditional surgical planning frequently relies on identifying the relevant anatomy at the time of surgery followed by planning and executing the plan in realtime. Advanced imaging (such as with CT scans) can be used to provide a valuable understanding of the underlying bony anatomy prior to surgery. Virtual surgical planning (VSP) uses CT (Computed Tomography) imaging studies to virtually perform the operation prior to surgery. VSP can also involve the use of custom, patient-specific cutting guides or plates to be used during surgery.

Applications of VSP in Facial Feminization Surgery (FFS)

Brow Bone Reduction: Brow bone reduction is a common procedure in facial feminization surgery (FFS) that is performed to reduce the prominence of brow bossing and create a smoother, more rounded contour. This is frequently performed either by shaving alone or by cutting and repositioning the anterior table of the frontal bone. With VSP, surgeons can precisely analyze the patient’s frontal bone morphology, plan osteotomies (bone cuts), and simulate the repositioning of the bone.¹ In some scenarios, computer-assisted surgical planning can allow for one to visualize the resulting soft tissue positions. This comprehensive approach can help surgeons prepare for an operation. That being noted, it is not a common practice for many facial feminization surgeons.

Rhinoplasty: Rhinoplasty, or nose reshaping surgery, is often performed to feminize the face. Virtual surgical planning (in its common meaning) is rarely performed in preparation for a rhinoplasty. Many surgeons will perform 2-dimensional image manipulation preoperatively with a patient to simulate the effects of a rhinoplasty. This form of image manipulation is generally not referred to as “virtual surgical planning” or “computer-assisted surgical planning.” Through the use of traditional image manipulation, surgeons can demonstrate to patients specific changes in the nasal anatomy. This commonly includes demonstrating changes in nasal tip projection, nasal tip rotation, and nasal bridge height. By simulating different changes to the nasal structure, surgeons and patients can better communicate. It allows the surgeon to show his surgical plan and it allows the patient to visualize the plan. Patients can then discuss whether the plan fits their desires or whether they have a different vision in mind. Standard image manipulation in this context can lead to more satisfactory outcomes.

Cheek Augmentation: Cheek augmentation is frequently employed to enhance facial femininity by augmenting the prominence of the cheekbones and creating a softer, more rounded facial contour. There are multiple methods for cheek augmentation. Two common surgical methods involve the use of implants or fat grafts. Commonly used cheek implants have been designed by implant companies to fit a wide range of facial structures. These frequently do not require patient-specific virtually planning. In contrast, surgeons sometimes want to use implants that are different from the standard “off-the-shelf” implants. This occurs when patients require augmentation in areas that are not augmented with standard implants or when patients have asymmetries that require discrepant implant shapes between the two sides of the face. Using VSP, surgeons can assess the patient’s facial symmetry, plan the placement of implants or, and simulate postoperative outcomes.

Jaw and Chin Surgery: Jaw and chin surgery, including mandibular contouring and genioplasty, can significantly impact facial gender presentation. VSP enables surgeons to analyze the relationship between the jaws, chin, and surrounding structures. It allows the surgeon to plan osteotomies or implant placements and simulate the desired changes in facial appearance. The areas commonly addressed with patient-specific computer-assisted surgical planning include the angles of the mandible and the chin. There are some techniques that involve removing the entire lower border of the mandible as part of the jaw reduction. ² When the angle is addressed separately, VSP is commonly performed to create custom, patient-specific cutting guides. These allow the surgeon to create symmetrical cuts on both sides of the jaw. When VSP is used for the chin, surgeons will create custom cutting guides to create precise, pre-planned cuts. Custom patient-specific plates can be used to secure the chin segments into pre-planned positions.³

Applications of VSP in Facial Masculinization Surgery (FMS)

In facial masculinization surgery (FMS), VSP offers similar advantages in terms of precision and customization. Procedures such as brow and jaw augmentation can be planned and simulated using VSP, allowing surgeons to achieve a specific degree of enhancement in each area of the face. Rhinoplasty is commonly addressed with standard 2-dimensional image manipulation as previously mentioned above.

Drawbacks of VSP in Gender-Affirming Surgery

Virtual surgical planning has relatively few drawbacks. The primary drawbacks include the additional time, expertise, and cost required for implementing the services. The additional time comes from scheduling a planning session and going through the specific requirements of the operation. For routine operations, VSP is often not necessary for achieving the desired results, so this extra step can be seen as unnecessary. VSP frequently involves complex manipulation of 3D structures in virtual space using proprietary software. This manipulation is frequently performed by engineers whose specialize in VSP manipulation and have spent a significant amount of time learning the software and necessary medical language. Each step in the computer-assisted surgical planning process involves a cost. These steps include planning and creation of the custom cutting guides and implants. Custom cutting guides and implants are significantly costlier than standard implants. These costs are then carried by the patient, the surgeon, the hospital system, or the insurance company.

Summary

VSP in gender-affirming facial surgery can be useful for approaching unique, patient-specific situations. It allows the surgeon to virtually consider the operation and create a plan prior to the day of surgery. Virtual planning can sometimes allow the surgeon to recognize areas of concern or difficulty that may not be obvious prior to surgery. Furthermore, it allows for the creation of custom cutting guides, custom plates, or custom implants. When used appropriately, this can improve patient symmetry. The downsides of virtual surgical planning include the additional cost and time associated with the process. Virtual surgical planning represents a change in the field of gender-affirming facial surgery that can improve the level of precision and personalization when used appropriately and responsibly.

Dr. Mittermiller has had in-depth experience with virtual surgical planning in multiple clinical scenarios. He has assisted with book and journal publications on the topics, has peer-reviewed manuscripts on the subject, and when indicated uses computer-assisted surgical planning in his own surgical practice. ^{4, 5}

Citations

1. Gray R, Nguyen K, Lee JC, Jordan Deschamps-Braly, Nicholas Bastidas, Tanna N, James Bradley (2019) Osseous Transformation with Facial Feminization Surgery: Improved Anatomical Accuracy with Virtual Planning. Plast Reconstr Surg 144 (5):1159-1168. doi:10.1097/PRS.0000000000006166 https://pubmed.ncbi.nlm.nih.gov/31397786/
2. Simon D, Capitan L, Bailon C, Bellinga RJ, Gutierrez-Santamaria J, Tenorio T, Sanchez-Garcia A, Capitan-Canadas F – Facialteam (2022) Facial Gender Confirmation Surgery: The Lower Jaw. Description of Surgical Techniques and Presentation of Results. Plastic and Reconstructive Surgery 149 (4):755e-766e. doi:10.1097/PRS.0000000000008969 https://pubmed.ncbi.nlm.nih.gov/35188904/
3. Michael Alperovich (2022) Commentary: Virtual Surgical Planning and Patient-Specific Implants in Facial Feminization Surgery. Facial Plast Surg Aesthet Med 24 (S2):S20-S23. doi:10.1089/fpsam.2022.0302
4. Flores RL, Mittermiller PA, Shetye PR (2024) Computer-Assisted Surgical Planning for Craniofacial Microsomia. In: Dorafshar A, Lopez J, Reid R (eds) Computer-Assisted Planning in Craniofacial Surgery. Elsevier, Philadelphia. https://www.mea.elsevierhealth.com/computer-assisted-planning-in-craniofacial-surgery-9780323826686.html
5. Andrew TW, Baylan J, Mittermiller PA, Cheng H, Johns DN, Edwards MSB, Cheshier SH, Grant GA, Lorenz HP (2018) Virtual Surgical Planning Decreases Operative Time for Isolated Single Suture and Multi-suture Craniosynostosis Repair. Plastic and Reconstructive Surgery Global Open 6 (12):e2038 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6326593/