Aesth Plast Surg (2014) 38:941–945 DOI 10.1007/s00266-014-0342-2
CASE REPORT
CRANIOFACIAL/MAXILLOFACIAL
Virtual Surgical Planning for Extensive Fibrous Dysplasia in the Mandible R. Villar-Puchades • B. Ramos-Medina
Received: 11 May 2013 / Accepted: 2 May 2014 / Published online: 23 August 2014 Ó Springer Science+Business Media New York and International Society of Aesthetic Plastic Surgery 2014
Abstract The reconstruction of extensive mandibular defects is a challenge for which virtual surgical planning is extremely helpful. This report describes the case of a 33-year-old woman who experienced the gradual development of a severe mandibular deformity with elongation of the chin and mandibular border because of fibrous dysplasia. Consequently, 19 cm of the mandible extending from the neck of the condyle to the contralateral body was resected together with vestibular and lingual deformities. This bone was replaced with a fibula-free flap. For planning, a virtual resection was performed via a Web conference, followed by virtual reconstruction by superimposition of the fibula on the mandibular defect after the creation of three osteotomies. A stereolithographic model of the reconstructed mandible and cutting guides for the mandibular resection and fibula osteotomies were made. The stereolithographic model of the neo-mandible allowed prebending of a reconstruction plate before the surgery because the deformity did not allow this to be performed intraoperatively. The cutting guides shortened the operating time and enabled accurate reproduction of the virtual plan with exact bone-to-bone contact in the reconstructed mandible. Surgical virtual planning, despite its
R. Villar-Puchades B. Ramos-Medina Oral and Maxilofacial Surgery Department, Hospital Universitario Santa Lucı´a, Calle Mezquita s/n, Paraje Los Arcos, 30202 Cartagena, Murcia, Spain R. Villar-Puchades (&) Calle Angel Bruna n812, 1aA, 30203 Cartagena, Murcia, Spain e-mail: [email protected]
upfront cost, is a time-saving procedure, which is especially important in complex reconstruction cases, and eliminates the variability of surgical expertise for flap insetting. Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. Keywords Surgical virtual planning Fibula flap Extensive fibrous dysplasia
Introduction In 1989, Hidalgo [1] introduced the free fibula flap for mandibular reconstruction. This flap is especially important for wide mandibular defects because it provides a long bone with a long vascular pedicle and allows incorporation of muscle and skin paddles via the vascular perforators. Traditionally, fibula in-setting has relied on manual skills and surgical expertise to reproduce the curves and shape of the mandible from a straight bone. The results are extremely dependent on the surgeon’s skill. With improvements in computer software in the late 1990s, virtual surgical planning has been applied to head and neck reconstruction [2, 3]. Three-dimensional images and computer-aided design software permits virtual surgical planning, and computer-aided manufacturing permits the production of stereolithographic models and surgical guides for the pre- and intraoperative steps. We present our experience with surgical virtual planning for the reconstruction of an extensive mandibular defect using a fibulafree flap.
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Aesth Plast Surg (2014) 38:941–945
Fig. 3 Orthopantomagraph: Extension of the disease from the 4.4 to the left subcondilar region
partial mandibular resection and reconstruction with free corticocancellous grafts from the hip. Unfortunately, the deformity continued to grow, as seen in the clinical and orthopantomograph images (Figs. 1, 2 and 3). High-resolution helical computed tomography (CT) of the mandible and CT angiography of the legs were obtained and sent to Medical Modeling Inc., Golden, Colorado.
Results Fig. 1 Chin and mandibular excess due to fibrous dysplasia
Fig. 2 Expansion of the lesion buccally and occlusally
Virtual Surgical Planning A Web conference was held between a biomedical engineer and the maxillofacial surgeon. Based on the tumor characteristics, virtual resection was performed from the left neck of the condyle to the right mandibular body. Virtual reconstruction was followed by superimposing the fibula onto the mandibular defect, with the necessary fibula osteotomies to recreate a mandible. Three osteotomies of the fibula were recreated: one based on the desired angle of the mandible and two more to reproduce the mandibular symphysis. A resin stereolithographic model of the reconstructed mandible and cutting guides for the mandible and fibula were manufactured (Fig. 4). Before the operation, the reconstruction plate was prebent using the stereolithographically reconstructed mandible and sterilized together with the cutting guides. Surgical Procedure
Materials and Methods Case Report A 33-year-old woman presented with a severe mandibular deformity that had developed during 10 years with elongation of the chin and mandibular border and intraoral growth on the vestibular and lingual sides due to fibrous dysplasia. The woman 5 years earlier had undergone a
123
The surgery was performed by two teams. A bilateral cervical approach was used to expose the mandible, which was resected with the mandible cutting guides. They were screwed to the native mandible and guided the osteotomies made with a reciprocating saw. The right facial artery and vein were dissected up to the mandibular body to reach the fibula pedicle. The vestibular and lingual deformity of the mandible caused by the disease did not allow us to prebend a
Aesth Plast Surg (2014) 38:941–945
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Fig. 4 Virtual surgical planning leading to a guided intraoperative procedure
Fig. 5 Mandibulectomy and the resin model stereolithography used to prebend the reconstruction plate
reconstruction plate, and the remaining head of the condyle did not allow placement of a transitional plate to hold both extremities of the mandible in their previous relation. A precontoured plate based on a stereolithographic model is one of the options that can be used to maintain the functional relation of the bony segments (Fig. 5).
Simultaneously, the left fibula was dissected using a lateral approach, with 6 cm of bone preserved proximally and distally for a harvest of the maximum bone possible and a vascular pedicle 21 cm long, with 1.5 and 3 mm of the caliber for the peroneal artery and the vein, respectively.
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Aesth Plast Surg (2014) 38:941–945
Fig. 6 Prebent reconstruction plate secured to the fibula
Fig. 8 Three-dimensional computed tomography (3D-CT) of the reconstructed mandible
Fig. 7 Postoperative profile
With the fibula still attached to the vascular pedicle, its cutting guide was secured with unicortical screws, and the osteotomies were performed, with care taken to protect the vascular pedicle. The prebent reconstruction plate was secured to the fibula in the leg before ligation of the pedicle (Fig. 6). The fibula with the osteotomies and reconstruction plate were fixed to the native mandible, and the vascular anastomoses to the facial vessels were performed under a microscope. No postoperative complications occurred. The patient had an optimal aesthetic profile that will improve with prosthetic dental rehabilitation (Fig. 7). She presented a maximal mouth opening of 32 mm with no temporomandibular symptoms, and our assessment 6 months after the surgery confirmed bone union (Figs. 8, 9).
123
Fig. 9 Temporomandibular joint
Discussion Fibrous dysplasia is a benign fibro-osseous bone disease in which normal bone is replaced by cellular fibrous tissue and immature bone. The monostotic form of the disease is more common than the polyostotic form. The disorder affects only one bone, and there are no systemic manifestations. Growth normally stops after puberty but can continue into early adulthood. Treatment is based on cosmetic and functional needs. Cosmetic contouring is an accepted
Aesth Plast Surg (2014) 38:941–945
945
Table 1 Differences between virtual surgical planning (VSP) and postoperative values
Length of fibula fragments (mm)
VSP
Postoperative
2.70
2.63
3.72
3.52
6.70
6.70
3.42
3.41
Angle mandible (°)
129
129
Bone-to-bone contact
Excellent
Excellent
We disclose any commercial interest or source of any financial or material support
treatment, but when the deformity is large, more aggressive treatment is indicated, as in the reported case [4]. Microvascular flap reconstruction is necessary when the mandible is resected from the neck of the condyle to the contralateral body of the mandible. The defect in the reported patient measured 19 cm, and the most likely bone flap adequate for that length is a fibula. The reconstruction planning was difficult due to the extent of the defect and distortion of the mandible by the disease. We present the problems we faced and how we resolved them. The mandibular resection was estimated, and the reconstruction was planned from this. First, the pedicle was oriented on the right side of the neck because on the left side it would be too high on the mandibular ramus, resulting in a potential curve prone to thrombosis. Because no skin paddle was necessary, both legs were potentially available. For a right-handed patient, the left side is preferred. During the virtual reconstruction planning, the left fibula was turned 180° to make the upper side with the proximal pedicle fall on the right side of the neck. Three virtual osteotomies then were performed, allowing perfect boneto-bone contact. A virtual stereolithographic model was made to prebend the reconstruction plate before the surgery because the deformity in the native mandible made it impossible to do this intraoperatively. Surgical guides permit transfer of the virtual surgical plan to the actual procedure, shortening the operating time while increasing the accuracy of the reproduction of the virtual surgical plan. Differences between the virtual surgical planning and the postoperative values were measured (Table 1). To reduce the ischemia time, all the osteotomies and the reconstruction plate were made on the fibula while it was still attached to its pedicle. A 2.0 mm reconstruction plate was used to provide adequate stability without postoperative exposure. Previous reports suggest that virtual surgical planning reduces the operating time and increases the surgical accuracy in head and neck reconstruction [5–10].
Conclusions To achieve an optimal aesthetic and functional result in extensive, complex mandibular reconstructions, virtual surgical planning to obtain stereolithographic models and surgical guides is strongly recommended. Although more expensive up front, it reduces costs by shortening the operation, which is critical in free flap reconstruction, decreasing the ischemia time. It also permits more accurate, predictable results with an adequate bone-to-bone contact. In addition, it allows the reconstruction plates to be prebent when the shape of the mandible is altered. Conflict of Interest The author declare that they have no conflicts of interest to disclose.
References 1. Hidalgo DA (1989) Fibula free flap: a new method of mandible reconstruction. Plast Reconst Surg 84:71–79 2. Eckard A, Swennen GR (2005) Virtual planning of composite mandibular reconstruction with free fibula bone graft. J Craniofac Surg 16:1137–1140 3. Hirsch DL, Garfein ES, Christensen AM, Weimer KA, Saddeh PB, Levine JP (2009) Use of computer-aided design and computer-aided manufacturing to produce orthognathically ideal surgical outcomes: a paradigma shift in head and neck reconstruction. J Oral Maxillofac Surg 67:2115–2122 4. Valentini V, Cassoni A, Marianetti TM, Terenzi V, Fadda MT, Iannetti G (2009) Craniomaxillofacial fibrous dysplasia: Conservative treatment or radical surgery? A retrospective study on 68 patients. Plast Reconst Surg 123:653–660 5. Antony AK, Chen WF, Klokytas A, Weimer KA, Cohen MN (2011) Use of virtual surgery and stereolithography-guided osteotomy for mandibular reconstruction with the free fibula. Plast Reconst Surg 128:1080–1084 6. Roser SM, Ramachandra S, Blair H, Grist W, Carlson GW, Christensen AM, Weimer KA, Steed MB (2010) The accuracy of virtual surgical planning in free fibula mandibular reconstruction: Comparison of planned and final results. J Oral Maxillofac Surg 68:2824–2832 7. Wang WH, Zhu J, Deng JY, Xia B, Xu B (2013) Three-dimensional virtual technology in reconstruction of mandibular defect including condyle using double-barrel vascularized fibula flap. J Craniomaxillofac Surg 41:417–422 8. Foley BD, Thayer WP, Honeybrook A, McKenna S, Press S (2013) Mandibular reconstruction using computer-aided design and computer-aided manufacturing: An analysis of surgical results. J Oral Maxillofac Surg 71:e111–e119 9. Shen Y, Sun J, Li J, Ji T, Li MM, Huang W, Hu M (2012) Using computer simulation and stereomodel for accurate mandibular reconstruction with vascularized iliac cresta flap. Oral Surg Oral Med Oral Pathol Oral Radiol 114:175–182 10. Zheng GS, Su YX, Liao GQ, Chen ZF, Wang L, Jiao PF, Liu HC, Zhong YQ, Zhang TH, Liang YJ (2012) Mandible reconstruction assisted by preoperative virtual surgical simulation. Oral Surg Oral Med Oral Pathol Oral Radiol 113:604–611
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CASE REPORT
CRANIOFACIAL/MAXILLOFACIAL
Virtual Surgical Planning for Extensive Fibrous Dysplasia in the Mandible R. Villar-Puchades • B. Ramos-Medina
Received: 11 May 2013 / Accepted: 2 May 2014 / Published online: 23 August 2014 Ó Springer Science+Business Media New York and International Society of Aesthetic Plastic Surgery 2014
Abstract The reconstruction of extensive mandibular defects is a challenge for which virtual surgical planning is extremely helpful. This report describes the case of a 33-year-old woman who experienced the gradual development of a severe mandibular deformity with elongation of the chin and mandibular border because of fibrous dysplasia. Consequently, 19 cm of the mandible extending from the neck of the condyle to the contralateral body was resected together with vestibular and lingual deformities. This bone was replaced with a fibula-free flap. For planning, a virtual resection was performed via a Web conference, followed by virtual reconstruction by superimposition of the fibula on the mandibular defect after the creation of three osteotomies. A stereolithographic model of the reconstructed mandible and cutting guides for the mandibular resection and fibula osteotomies were made. The stereolithographic model of the neo-mandible allowed prebending of a reconstruction plate before the surgery because the deformity did not allow this to be performed intraoperatively. The cutting guides shortened the operating time and enabled accurate reproduction of the virtual plan with exact bone-to-bone contact in the reconstructed mandible. Surgical virtual planning, despite its
R. Villar-Puchades B. Ramos-Medina Oral and Maxilofacial Surgery Department, Hospital Universitario Santa Lucı´a, Calle Mezquita s/n, Paraje Los Arcos, 30202 Cartagena, Murcia, Spain R. Villar-Puchades (&) Calle Angel Bruna n812, 1aA, 30203 Cartagena, Murcia, Spain e-mail: [email protected]
upfront cost, is a time-saving procedure, which is especially important in complex reconstruction cases, and eliminates the variability of surgical expertise for flap insetting. Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. Keywords Surgical virtual planning Fibula flap Extensive fibrous dysplasia
Introduction In 1989, Hidalgo [1] introduced the free fibula flap for mandibular reconstruction. This flap is especially important for wide mandibular defects because it provides a long bone with a long vascular pedicle and allows incorporation of muscle and skin paddles via the vascular perforators. Traditionally, fibula in-setting has relied on manual skills and surgical expertise to reproduce the curves and shape of the mandible from a straight bone. The results are extremely dependent on the surgeon’s skill. With improvements in computer software in the late 1990s, virtual surgical planning has been applied to head and neck reconstruction [2, 3]. Three-dimensional images and computer-aided design software permits virtual surgical planning, and computer-aided manufacturing permits the production of stereolithographic models and surgical guides for the pre- and intraoperative steps. We present our experience with surgical virtual planning for the reconstruction of an extensive mandibular defect using a fibulafree flap.
123
942
Aesth Plast Surg (2014) 38:941–945
Fig. 3 Orthopantomagraph: Extension of the disease from the 4.4 to the left subcondilar region
partial mandibular resection and reconstruction with free corticocancellous grafts from the hip. Unfortunately, the deformity continued to grow, as seen in the clinical and orthopantomograph images (Figs. 1, 2 and 3). High-resolution helical computed tomography (CT) of the mandible and CT angiography of the legs were obtained and sent to Medical Modeling Inc., Golden, Colorado.
Results Fig. 1 Chin and mandibular excess due to fibrous dysplasia
Fig. 2 Expansion of the lesion buccally and occlusally
Virtual Surgical Planning A Web conference was held between a biomedical engineer and the maxillofacial surgeon. Based on the tumor characteristics, virtual resection was performed from the left neck of the condyle to the right mandibular body. Virtual reconstruction was followed by superimposing the fibula onto the mandibular defect, with the necessary fibula osteotomies to recreate a mandible. Three osteotomies of the fibula were recreated: one based on the desired angle of the mandible and two more to reproduce the mandibular symphysis. A resin stereolithographic model of the reconstructed mandible and cutting guides for the mandible and fibula were manufactured (Fig. 4). Before the operation, the reconstruction plate was prebent using the stereolithographically reconstructed mandible and sterilized together with the cutting guides. Surgical Procedure
Materials and Methods Case Report A 33-year-old woman presented with a severe mandibular deformity that had developed during 10 years with elongation of the chin and mandibular border and intraoral growth on the vestibular and lingual sides due to fibrous dysplasia. The woman 5 years earlier had undergone a
123
The surgery was performed by two teams. A bilateral cervical approach was used to expose the mandible, which was resected with the mandible cutting guides. They were screwed to the native mandible and guided the osteotomies made with a reciprocating saw. The right facial artery and vein were dissected up to the mandibular body to reach the fibula pedicle. The vestibular and lingual deformity of the mandible caused by the disease did not allow us to prebend a
Aesth Plast Surg (2014) 38:941–945
943
Fig. 4 Virtual surgical planning leading to a guided intraoperative procedure
Fig. 5 Mandibulectomy and the resin model stereolithography used to prebend the reconstruction plate
reconstruction plate, and the remaining head of the condyle did not allow placement of a transitional plate to hold both extremities of the mandible in their previous relation. A precontoured plate based on a stereolithographic model is one of the options that can be used to maintain the functional relation of the bony segments (Fig. 5).
Simultaneously, the left fibula was dissected using a lateral approach, with 6 cm of bone preserved proximally and distally for a harvest of the maximum bone possible and a vascular pedicle 21 cm long, with 1.5 and 3 mm of the caliber for the peroneal artery and the vein, respectively.
123
944
Aesth Plast Surg (2014) 38:941–945
Fig. 6 Prebent reconstruction plate secured to the fibula
Fig. 8 Three-dimensional computed tomography (3D-CT) of the reconstructed mandible
Fig. 7 Postoperative profile
With the fibula still attached to the vascular pedicle, its cutting guide was secured with unicortical screws, and the osteotomies were performed, with care taken to protect the vascular pedicle. The prebent reconstruction plate was secured to the fibula in the leg before ligation of the pedicle (Fig. 6). The fibula with the osteotomies and reconstruction plate were fixed to the native mandible, and the vascular anastomoses to the facial vessels were performed under a microscope. No postoperative complications occurred. The patient had an optimal aesthetic profile that will improve with prosthetic dental rehabilitation (Fig. 7). She presented a maximal mouth opening of 32 mm with no temporomandibular symptoms, and our assessment 6 months after the surgery confirmed bone union (Figs. 8, 9).
123
Fig. 9 Temporomandibular joint
Discussion Fibrous dysplasia is a benign fibro-osseous bone disease in which normal bone is replaced by cellular fibrous tissue and immature bone. The monostotic form of the disease is more common than the polyostotic form. The disorder affects only one bone, and there are no systemic manifestations. Growth normally stops after puberty but can continue into early adulthood. Treatment is based on cosmetic and functional needs. Cosmetic contouring is an accepted
Aesth Plast Surg (2014) 38:941–945
945
Table 1 Differences between virtual surgical planning (VSP) and postoperative values
Length of fibula fragments (mm)
VSP
Postoperative
2.70
2.63
3.72
3.52
6.70
6.70
3.42
3.41
Angle mandible (°)
129
129
Bone-to-bone contact
Excellent
Excellent
We disclose any commercial interest or source of any financial or material support
treatment, but when the deformity is large, more aggressive treatment is indicated, as in the reported case [4]. Microvascular flap reconstruction is necessary when the mandible is resected from the neck of the condyle to the contralateral body of the mandible. The defect in the reported patient measured 19 cm, and the most likely bone flap adequate for that length is a fibula. The reconstruction planning was difficult due to the extent of the defect and distortion of the mandible by the disease. We present the problems we faced and how we resolved them. The mandibular resection was estimated, and the reconstruction was planned from this. First, the pedicle was oriented on the right side of the neck because on the left side it would be too high on the mandibular ramus, resulting in a potential curve prone to thrombosis. Because no skin paddle was necessary, both legs were potentially available. For a right-handed patient, the left side is preferred. During the virtual reconstruction planning, the left fibula was turned 180° to make the upper side with the proximal pedicle fall on the right side of the neck. Three virtual osteotomies then were performed, allowing perfect boneto-bone contact. A virtual stereolithographic model was made to prebend the reconstruction plate before the surgery because the deformity in the native mandible made it impossible to do this intraoperatively. Surgical guides permit transfer of the virtual surgical plan to the actual procedure, shortening the operating time while increasing the accuracy of the reproduction of the virtual surgical plan. Differences between the virtual surgical planning and the postoperative values were measured (Table 1). To reduce the ischemia time, all the osteotomies and the reconstruction plate were made on the fibula while it was still attached to its pedicle. A 2.0 mm reconstruction plate was used to provide adequate stability without postoperative exposure. Previous reports suggest that virtual surgical planning reduces the operating time and increases the surgical accuracy in head and neck reconstruction [5–10].
Conclusions To achieve an optimal aesthetic and functional result in extensive, complex mandibular reconstructions, virtual surgical planning to obtain stereolithographic models and surgical guides is strongly recommended. Although more expensive up front, it reduces costs by shortening the operation, which is critical in free flap reconstruction, decreasing the ischemia time. It also permits more accurate, predictable results with an adequate bone-to-bone contact. In addition, it allows the reconstruction plates to be prebent when the shape of the mandible is altered. Conflict of Interest The author declare that they have no conflicts of interest to disclose.
References 1. Hidalgo DA (1989) Fibula free flap: a new method of mandible reconstruction. Plast Reconst Surg 84:71–79 2. Eckard A, Swennen GR (2005) Virtual planning of composite mandibular reconstruction with free fibula bone graft. J Craniofac Surg 16:1137–1140 3. Hirsch DL, Garfein ES, Christensen AM, Weimer KA, Saddeh PB, Levine JP (2009) Use of computer-aided design and computer-aided manufacturing to produce orthognathically ideal surgical outcomes: a paradigma shift in head and neck reconstruction. J Oral Maxillofac Surg 67:2115–2122 4. Valentini V, Cassoni A, Marianetti TM, Terenzi V, Fadda MT, Iannetti G (2009) Craniomaxillofacial fibrous dysplasia: Conservative treatment or radical surgery? A retrospective study on 68 patients. Plast Reconst Surg 123:653–660 5. Antony AK, Chen WF, Klokytas A, Weimer KA, Cohen MN (2011) Use of virtual surgery and stereolithography-guided osteotomy for mandibular reconstruction with the free fibula. Plast Reconst Surg 128:1080–1084 6. Roser SM, Ramachandra S, Blair H, Grist W, Carlson GW, Christensen AM, Weimer KA, Steed MB (2010) The accuracy of virtual surgical planning in free fibula mandibular reconstruction: Comparison of planned and final results. J Oral Maxillofac Surg 68:2824–2832 7. Wang WH, Zhu J, Deng JY, Xia B, Xu B (2013) Three-dimensional virtual technology in reconstruction of mandibular defect including condyle using double-barrel vascularized fibula flap. J Craniomaxillofac Surg 41:417–422 8. Foley BD, Thayer WP, Honeybrook A, McKenna S, Press S (2013) Mandibular reconstruction using computer-aided design and computer-aided manufacturing: An analysis of surgical results. J Oral Maxillofac Surg 71:e111–e119 9. Shen Y, Sun J, Li J, Ji T, Li MM, Huang W, Hu M (2012) Using computer simulation and stereomodel for accurate mandibular reconstruction with vascularized iliac cresta flap. Oral Surg Oral Med Oral Pathol Oral Radiol 114:175–182 10. Zheng GS, Su YX, Liao GQ, Chen ZF, Wang L, Jiao PF, Liu HC, Zhong YQ, Zhang TH, Liang YJ (2012) Mandible reconstruction assisted by preoperative virtual surgical simulation. Oral Surg Oral Med Oral Pathol Oral Radiol 113:604–611
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