Three-Dimensional Virtual Surgery Accuracy for Free Fibula Mandibular Reconstruction: Planned Versus Actual Results

doi:10.1016/j.joms.2014.07.024

Journal of Oral and Maxillofacial Surgery

Volume 72, Issue 12, December 2014, Pages 2601-2612

https://doi.org/10.1016/j.joms.2014.07.024 Get rights and content

Purpose

Virtual surgical planning (VSP) can promote efficiency, but the ability to transfer the proposed plan to the actual result has not been adequately studied. The purpose of this study was to morphometrically compare the virtually preplanned scenario with the postoperative 3-dimensional (3D) anatomic result.

Materials and Methods

A retrospective review of 10 patients who underwent mandibular reconstruction using a free fibula flap and VSP were evaluated. Pre- and postoperative Digital Imaging and Communications in Medicine files were imported into Mimics 10.01 software (Materialise, Leuven, Belgium) for surgical planning. Preoperative VSP and 1-week postoperative computed tomographic (CT) scans were evaluated to assess surgical accuracy using VSP. The pre- and postoperative morphometric measurements were compared using the Student t test.

Results

Twenty CT scans from 10 patients (mean age, 56.9 ± 20.2 yr) who underwent partial mandibular resection were analyzed. The dimensions of the fibula segments after osteotomy showed no difference from the preoperative VSP (mean difference in fibula height, 1.2 mm; mean difference in width, 0.9 mm; mean difference in length, 1.3 mm). The postoperative anterior and posterior mandibular angles differed from the VSP by 12.4° and −12.5°, respectively. The condylar distance and inclination showed a discrepancy of only 1.7 mm and 4.6°, respectively, between VSP and postoperative CT scans.

Conclusions

VSP confers reproducible precision and accuracy for free fibular mandibular reconstruction. The benefit was most striking for large reconstructions requiring multiple fibular segments. Future directions include assessing the use of external registration devices to enhance surgical accuracy and to follow patients longitudinally to monitor the long-term benefit of VSP.

Section snippets

Study Design

This retrospective analysis was performed in concordance with the Yale University institutional review board (New Haven; HIC# 1101007932). Ten patients who underwent mandibular reconstruction using an FFF and 3D planning at Yale New Haven Hospital from November 2012 through 2013 by a single surgeon (D.M.S.) were included. Patients’ age, gender, and diagnosis were documented as were perioperative details, such as the area of resection and the number of segments used for the reconstruction.

Data Collection

Results

Twenty scans were analyzed; 10 patients who underwent mandibular resection and simultaneous reconstruction using an FFF were included (Figure 3, Figure 4). Patients’ ages ranged from 26 to 89 years (mean, 56.9 ± 20.2 yr). The male-to-female ratio was 4:1. Six patients underwent surgery for oral malignancies involving the mandibular bone (Table 3). In total, 28 osteotomies within the fibula bone were performed.

The results of the morphometric analysis are presented in Table 4. Mean PMA of the

Discussion

Large mandibular defects impart functional and esthetic consequences that are lessened when proper and accurate reconstruction is performed. The mandible exhibits a complex 3D configuration, with mobile articulations and muscle attachments that can alter the relation of the mandible to the maxilla and skull base and to itself (eg, mandibular segment arc collapse or rotation). The use of internal and external landmarks and reference points as an aid to maintain and re-establish mandibular

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Surgical oncology and reconstructionThree-Dimensional Virtual Surgery Accuracy for Free Fibula Mandibular Reconstruction: Planned Versus Actual Results

Purpose

Materials and Methods

Results

Conclusions

Section snippets

Study Design

Data Collection

Results

Discussion

Atlas Oral Maxillofac Surg Clin North Am

J Craniomaxillofac Surg

J Craniomaxillofac Surg

J Oral Maxillofac Surg

Int J Oral Maxillofac Surg

J Oral Maxillofac Surg

J Oral Maxillofac Surg

J Oral Maxillofac Surg

Oral Surg Oral Med Oral Pathol Oral Radiol

J Oral Maxillofac Surg

Surgical oncology and reconstruction
Three-Dimensional Virtual Surgery Accuracy for Free Fibula Mandibular Reconstruction: Planned Versus Actual Results