ANATOMICAL STUDY
Segmental Masseteric Flap for Dynamic Reanimation of Facial Palsy Marco Romeo, MD,* Yee Jun Lim, MD,Þ Quentin Fogg, PhD,þ and Stephen Morley, MD, FRCS* Abstract: The masseter muscle is one of the major chewing muscles and contributes to define facial contour. It is an important landmark for aesthetic and functional surgery and has been used for facial palsy reanimation or as source of donor motor nerve. We present an anatomic study to evaluate the possibility of using a muscle subunit for dynamic eye reanimation. Sixteen head halves were dissected under magnification to study the neurovascular distribution and determine safe muscle subunits; areas of safe/dangerous dissection were investigated. Once isolated, the arc of rotation of the muscular subunit was measured on fresh body to verify the reach to the lateral canthus. The patterns of neurovascular distribution and areas of safe dissection were identified; the anterior third of the muscle represents an ideal subunit with constant nerve and artery distribution. The muscle is too short to reach the lateral canthus; a fascia graft extension is needed. The information provided identified the main neurovascular branches and confirms the feasibility of a dynamic segmental flap. The need of efficient motor units for facial reanimation demands for different surgical options. A detailed anatomic description of the neurovascular bundle is mandatory to safely raise a functional motor subunit. Key Words: Masseter, anatomy, flap, facial, palsy, reanimation (J Craniofac Surg 2014;25: 630Y632)
T
he masseter is the most powerful chewing muscle. It is made up of 2 or 3 layers of fibers,1 which insert cranially on the lower border of the zygomatic arch and caudally on the angle of the mandible and its horizontal ramus. The layers have different orientation: the deep layers have a rather vertical direction, whereas the superficial one has a more oblique orientation from posterior to anterior and from cranial to caudal direction2 and eventually merge as they go downward. Vascularity is mainly guaranteed by the masseteric branch of the maxillary artery, whereas the facial artery reaches the lower border of the muscle.3,4 It has a relevant role in mandible elevation and determination of facial contour. Previous studies have demonstrated the possibility of selective neurotomies5 for aesthetic surgery. The use of the whole muscle for facial From the *Canniesburn Plastic Surgery Unit, Glasgow Royal Infirmary; †Department of Anatomy and ‡School of Medicine, University of Glasgow, Glasgow, United Kingdom. Received November 14, 2013. Accepted for publication December 2, 2013. Address correspondence and reprint requests to Marco Romeo, MD, Canniesburn Plastic Surgery Unit, Glasgow Royal Infirmary, 84 Castle St Glasgow, Glasgow City G4 0SF, United Kingdom; E-mail: [email protected] The authors report no conflicts of interest. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000648
630
reanimation was firstly described by Lexer.6 Later, other authors used it with or without fascia extension graft7,8 for reanimation of the lower third of the face. This article studies the neurovascular distribution of the masseter to clarify the possibility to raise an innervated subunit of muscle to reach the orbital region.
MATERIALS AND METHODS Masseter Dissection Sixteen hemifaces (8 heads) of embalmed cadavers were dissected to study the neurovascular distribution of the masseter. All heads belonged to adult cadavers (mean age, 74 y; range, 55Y86 y; male, 12; female, 4). The skin and soft tissues overlying the masseter including the superficial muscular aponeurotic system and the parotid gland were removed after a standard facelift access along the preauricular area; in this phase, the facial nerve is killed to allow a better exposure. A further horizontal incision on the angle of the mandible allows full exposure of the muscle. The masseter is released from its attachments on the zygomatic arch and mandible; the pedicle is identified at the mandibular notch and eventually cut.
Intramuscular Dissection Under a magnification of 10, ‘‘open cast’’ dissection is carried out to describe the peripheral course of the neurovascular bundle to the muscle periphery exposing the nerve terminal branches as far as microdissection allowed. The muscle is ideally divided in 3 longitudinal portions (Fig. 1); the distance of the nerve from the inferior edge is recorded at the junction of each of the 3 portions. The shortest distance between the gonion, corresponding to the posterior inferior angle of the muscle, and the nerve was recorded, describing a circle to define an area of safe dissection; the distance corresponds to the radius of the circle itself (Fig. 2). The ramification patterns, depth, and position of the nerve at each third were recorded. The combination of all the measurements provides the mean position of the main bifurcation of the nerve inside the muscle: this is the pivot point P of the flap (Fig. 3). From point P, the distance to the lower border of the mandible (A) and the lateral canthus (B) is recorded. Distances A and B are compared to understand the degree of rotation of the muscle flap around point P. The nerve-artery relationship was noted from the origin of the artery to the terminal branches. Once a subunit flap was identified on the preserved specimens, the flap was tested on fresh cadaver to verify the arc of rotation to the lateral canthus.
RESULTS Vascular Anatomy The artery had a constant anatomy when it passes through the mandibular notch, except for a single vascular anomaly with the blood supply coming directly from external carotid artery but then after a usual intramuscular distribution. The artery ran between the
The Journal of Craniofacial Surgery
& Volume 25, Number 2, March 2014
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery
& Volume 25, Number 2, March 2014
FIGURE 1. The muscle is divided in 3 portions: the nerve distance from the lower border is recorded at the junction between each third. The portions follow the longitudinal direction of the muscle fibers.
deep and the superficial layer according to a 2-layer description of the muscle as it was found in the middle and superficial layers to be almost indistinguishable. Once the artery and the nerve enter in the superoposterior corner of the muscle, they promptly join to have a common course (Fig. 4).
Nerve Distribution and Flap Rising In all specimens, it was possible to define 2 distinct innervated muscle subunits: anterior and posterior. The main nerve bifurcation (point P) was found in the upper central portion of the muscle body, located in the middle third of the muscle occasionally crossing the edge between the middle and the anterior third. The distance of point P from the lower border of the mandible (A) was, in average, 63.1 mm (range, 25Y79 mm); the distance from the lateral canthus (B) was 54.4 mm (range, 48Y66 mm). Two patterns of distribution of nerve were found. The main branch to the anterior border was constant in both types of distribution, whereas a returning branch to the posterior portion of the muscle could either give a singular division (type 1) or divide in 2 smaller branches (type 2). Type 2 was found in 75% of the specimens; the remaining 25% was type 1. The main branch constantly
FIGURE 2. The area of safe dissection is defined, drawing a circle centered on the gonion: the radius corresponds to the closest point to the nerve.
Segmental Masseteric Flap
FIGURE 3. The poligonal area in the center of the drawing representing the masseter defines the mean position of artery bifurcation. This is the pivot point (Point P) that defines the arc of rotation of the anterior muscle flap.
sent small vessels to a narrow strip of muscle on the anterior edge. These branches penetrated the muscle fibres after a segmental distribution in a comblike fashion. Using the gonion as landmark, the area free of main neurovascular structures was identified. On the posterior third, the bundle has an average distance from inferior edge of 41.6 mm (range, 35Y49 mm). The bundle comes closer anteriorly crossing the middle third of the muscle at 24.9 mm in average (range, 31.6Y19.1 mm). Hence, the area free of relevant neurovascular structures is reduced from 41.6 to 24.9 mm on the anteroposterior plane as the nerve comes closer anteriorly (range, 14Y25 mm). In Figure 5, the portion of the muscle used as a flap is evidenced; in Figure 6, on a fresh cadaver, the flap was raised on the anterior third of the muscle with the artery and nerve identified. The muscle was then turned up to the lateral canthus. Despite the fact that segment A was proven to be larger than segment B, the rotation caused a loss of length of the flap, which made it impossible to reach the lateral canthus.
DISCUSSION The current criterion standard for facial palsy surgical therapy relies on free muscle transfer. Nevertheless, local muscle flaps are an important resource that should be part of the surgeon’s
FIGURE 4. Detail of the artery and nerve intimate relationship at the main bifurcation. Their proximity is maintained until the last visible ramification at muscle edge.
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
631
Romeo et al
The Journal of Craniofacial Surgery
armamentarium. The first described use of local flaps in recent history goes back to 1907 with Lexer6 using the anterior edge of the masseter muscle to lift up the angle of the mouth. Since then, the anterior portion of the muscle has been used by many authors9,10 to lift the angle of the mouth alone or in combination with eye reanimation11 by splitting the muscle in 2 subunits. In more recent times, De Castro Correia and Zani7 reported the first nerve anatomic study to allow safe muscle splitting. Shinohara12 proposed an interesting alternative by splitting the upper portion of the muscle elongated with a strip of fascia lata using the zygomatic arch as a pulley to reach the angle of the mouth. Hwang et al1 was the first to describe the various patterns of distribution and depth of the nerve inside the muscle but did not mention the relationship with the vascular bundle as Hontanilla and Qiu13 did, describing a ‘‘treelike’’ distribution with no further specification or pattern description. In our study, the nerve main division always gives 2 branches in the upper portion of the middle third of the muscle; the recurrent branch to the posterior muscle subunit is discarded because of its variability, whereas the anterior branch is followed to raise the anterior third as innervated flap, thanks to its segmental neurovascular distribution. Our data confirm and merge the findings of Hontanilla and Qiu13 (nerve-artery relationship) and Hwang et al1 (defined pattern of distribution), implementing the previous studies describing a ‘‘comblike’’ distribution in the anterior third of the muscle. Once the flap is flipped upward, a fascial extension is needed to reach the eye canthus similar to the temporalis muscle flap. The angle formed by the masseter and the corner of the eye is similar to the one defined in the temporal muscle flap described by Salimbeni.14 This study provides more evidence of the close relationship of the masseteric nerve and artery and confirms the possibility of raising the anterior third of the muscle, thanks to its rich innervation, as a multipurpose flap for local use to reach the corner of the mouth or the eye canthus, although its shortness requires tendon or fascia extension to easily reach the latter. Using the gonion as landmark helps to quickly identify the areas free of relevant nerve/artery distribution.
FIGURE 5. The superficial layer of the muscle is removed to show the bundle distribution. The rectangular area on the right third of the image defines the anterior portion of the muscle that is used as local flap.
632
& Volume 25, Number 2, March 2014
FIGURE 6. The flap is raised from a fresh cadaver. The thin arrow indicates the master muscle; the short arrow points at the neurovascular pedicle entering the flap.
These findings provide relevant information to the surgeon for a safer and more advanced surgical approach to the lateral face district and facial reanimation.
ACKNOWLEDGMENTS The authors thank the donors of the human bodies that allowed the realization of the study.
REFERENCES 1. Hwang K, Kim YJ, Chung IH, et al. Course of the masseteric nerve in masseter muscle. J Craniofac Surg 2005;16:197Y200 2. Rohe JW, Yokochi C, Lutjen-Drecoll E. Color Atlas of Anatomy: A Photographic Study of the Human Body. 7th ed. Baltimore, MD: Lippincott Williams & Wilkins; 2007:56Y83 3. Houseman ND, Taylor GI, PanW-R. The angiosomes of the head and neck: anatomic study and clinical applications. Plast Reconstr Surg 105:2287Y2313 4. Arijj Y, Kimura Y, Gotoh M, et al. Blood flow in and around the masseter muscle: normal and pathologic features demonstrated by color Doppler sonography. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2001;91:472Y482 5. Hwang K, Kim YJ, Park H, et al. Selective neurectomy of the masseteric nerve in masseter hypertrophy. J Craniofac Surg 2004;15:780Y784 6. AlexanderRJ.Correction of facial paralysis by muscle transplant. Rocky Mt Med J 1941;38:713Y716 7. De Castro Correia P, Zani R.Masseter muscle rotation in the treatment of inferior facial paralysis. Anatomical and clinical observations. Plast Reconstr Surg 1973;52:370Y373 8. Shinohara H, Matsuo K, OsadaY, et al.Facial reanimation by transposition of the masseter muscle combined with tensor fascia lata, using the zygomatic arch as a pulley. Scand J Plast Reconstr Surg Hand Surg 2008;42:17Y22 9. Adson AW .Surgical treatment of facial paralysis. Arch Otolaryngol Head Neck Surg 1925;2:217Y249 10. Hastings S. Transplantation of anterior half of masseter muscle for facial paralysis. Proc R Soc Med 1920;13:64Y65 11. Halle M .The occurrence of facial paralysis and methods for its correction. Laryngoscope 1938;48:225Y235 12. Shinohara H, Matsuo K, Osada TY, et al Alternative facial reanimation by masseter muscle transposition combined with tensor fascia lata using the zygomatic arch as a pulley. Scand J Plast Reconstr Surg Hand Surg 2008;42:17Y22 13. Hontanilla B, Qiu SS. Transposition of the hemimasseteric muscle for dynamic rehabilitation of facial paralysis. J Craniofac Surg 2012;23:203Y205 14. Salimbeni G. Eyelid reanimation in facial paralysis by temporalis muscle transfer. Oper Tech Plast Reconstr Surg 1999;6:159Y162
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
Segmental Masseteric Flap for Dynamic Reanimation of Facial Palsy Marco Romeo, MD,* Yee Jun Lim, MD,Þ Quentin Fogg, PhD,þ and Stephen Morley, MD, FRCS* Abstract: The masseter muscle is one of the major chewing muscles and contributes to define facial contour. It is an important landmark for aesthetic and functional surgery and has been used for facial palsy reanimation or as source of donor motor nerve. We present an anatomic study to evaluate the possibility of using a muscle subunit for dynamic eye reanimation. Sixteen head halves were dissected under magnification to study the neurovascular distribution and determine safe muscle subunits; areas of safe/dangerous dissection were investigated. Once isolated, the arc of rotation of the muscular subunit was measured on fresh body to verify the reach to the lateral canthus. The patterns of neurovascular distribution and areas of safe dissection were identified; the anterior third of the muscle represents an ideal subunit with constant nerve and artery distribution. The muscle is too short to reach the lateral canthus; a fascia graft extension is needed. The information provided identified the main neurovascular branches and confirms the feasibility of a dynamic segmental flap. The need of efficient motor units for facial reanimation demands for different surgical options. A detailed anatomic description of the neurovascular bundle is mandatory to safely raise a functional motor subunit. Key Words: Masseter, anatomy, flap, facial, palsy, reanimation (J Craniofac Surg 2014;25: 630Y632)
T
he masseter is the most powerful chewing muscle. It is made up of 2 or 3 layers of fibers,1 which insert cranially on the lower border of the zygomatic arch and caudally on the angle of the mandible and its horizontal ramus. The layers have different orientation: the deep layers have a rather vertical direction, whereas the superficial one has a more oblique orientation from posterior to anterior and from cranial to caudal direction2 and eventually merge as they go downward. Vascularity is mainly guaranteed by the masseteric branch of the maxillary artery, whereas the facial artery reaches the lower border of the muscle.3,4 It has a relevant role in mandible elevation and determination of facial contour. Previous studies have demonstrated the possibility of selective neurotomies5 for aesthetic surgery. The use of the whole muscle for facial From the *Canniesburn Plastic Surgery Unit, Glasgow Royal Infirmary; †Department of Anatomy and ‡School of Medicine, University of Glasgow, Glasgow, United Kingdom. Received November 14, 2013. Accepted for publication December 2, 2013. Address correspondence and reprint requests to Marco Romeo, MD, Canniesburn Plastic Surgery Unit, Glasgow Royal Infirmary, 84 Castle St Glasgow, Glasgow City G4 0SF, United Kingdom; E-mail: [email protected] The authors report no conflicts of interest. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000648
630
reanimation was firstly described by Lexer.6 Later, other authors used it with or without fascia extension graft7,8 for reanimation of the lower third of the face. This article studies the neurovascular distribution of the masseter to clarify the possibility to raise an innervated subunit of muscle to reach the orbital region.
MATERIALS AND METHODS Masseter Dissection Sixteen hemifaces (8 heads) of embalmed cadavers were dissected to study the neurovascular distribution of the masseter. All heads belonged to adult cadavers (mean age, 74 y; range, 55Y86 y; male, 12; female, 4). The skin and soft tissues overlying the masseter including the superficial muscular aponeurotic system and the parotid gland were removed after a standard facelift access along the preauricular area; in this phase, the facial nerve is killed to allow a better exposure. A further horizontal incision on the angle of the mandible allows full exposure of the muscle. The masseter is released from its attachments on the zygomatic arch and mandible; the pedicle is identified at the mandibular notch and eventually cut.
Intramuscular Dissection Under a magnification of 10, ‘‘open cast’’ dissection is carried out to describe the peripheral course of the neurovascular bundle to the muscle periphery exposing the nerve terminal branches as far as microdissection allowed. The muscle is ideally divided in 3 longitudinal portions (Fig. 1); the distance of the nerve from the inferior edge is recorded at the junction of each of the 3 portions. The shortest distance between the gonion, corresponding to the posterior inferior angle of the muscle, and the nerve was recorded, describing a circle to define an area of safe dissection; the distance corresponds to the radius of the circle itself (Fig. 2). The ramification patterns, depth, and position of the nerve at each third were recorded. The combination of all the measurements provides the mean position of the main bifurcation of the nerve inside the muscle: this is the pivot point P of the flap (Fig. 3). From point P, the distance to the lower border of the mandible (A) and the lateral canthus (B) is recorded. Distances A and B are compared to understand the degree of rotation of the muscle flap around point P. The nerve-artery relationship was noted from the origin of the artery to the terminal branches. Once a subunit flap was identified on the preserved specimens, the flap was tested on fresh cadaver to verify the arc of rotation to the lateral canthus.
RESULTS Vascular Anatomy The artery had a constant anatomy when it passes through the mandibular notch, except for a single vascular anomaly with the blood supply coming directly from external carotid artery but then after a usual intramuscular distribution. The artery ran between the
The Journal of Craniofacial Surgery
& Volume 25, Number 2, March 2014
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery
& Volume 25, Number 2, March 2014
FIGURE 1. The muscle is divided in 3 portions: the nerve distance from the lower border is recorded at the junction between each third. The portions follow the longitudinal direction of the muscle fibers.
deep and the superficial layer according to a 2-layer description of the muscle as it was found in the middle and superficial layers to be almost indistinguishable. Once the artery and the nerve enter in the superoposterior corner of the muscle, they promptly join to have a common course (Fig. 4).
Nerve Distribution and Flap Rising In all specimens, it was possible to define 2 distinct innervated muscle subunits: anterior and posterior. The main nerve bifurcation (point P) was found in the upper central portion of the muscle body, located in the middle third of the muscle occasionally crossing the edge between the middle and the anterior third. The distance of point P from the lower border of the mandible (A) was, in average, 63.1 mm (range, 25Y79 mm); the distance from the lateral canthus (B) was 54.4 mm (range, 48Y66 mm). Two patterns of distribution of nerve were found. The main branch to the anterior border was constant in both types of distribution, whereas a returning branch to the posterior portion of the muscle could either give a singular division (type 1) or divide in 2 smaller branches (type 2). Type 2 was found in 75% of the specimens; the remaining 25% was type 1. The main branch constantly
FIGURE 2. The area of safe dissection is defined, drawing a circle centered on the gonion: the radius corresponds to the closest point to the nerve.
Segmental Masseteric Flap
FIGURE 3. The poligonal area in the center of the drawing representing the masseter defines the mean position of artery bifurcation. This is the pivot point (Point P) that defines the arc of rotation of the anterior muscle flap.
sent small vessels to a narrow strip of muscle on the anterior edge. These branches penetrated the muscle fibres after a segmental distribution in a comblike fashion. Using the gonion as landmark, the area free of main neurovascular structures was identified. On the posterior third, the bundle has an average distance from inferior edge of 41.6 mm (range, 35Y49 mm). The bundle comes closer anteriorly crossing the middle third of the muscle at 24.9 mm in average (range, 31.6Y19.1 mm). Hence, the area free of relevant neurovascular structures is reduced from 41.6 to 24.9 mm on the anteroposterior plane as the nerve comes closer anteriorly (range, 14Y25 mm). In Figure 5, the portion of the muscle used as a flap is evidenced; in Figure 6, on a fresh cadaver, the flap was raised on the anterior third of the muscle with the artery and nerve identified. The muscle was then turned up to the lateral canthus. Despite the fact that segment A was proven to be larger than segment B, the rotation caused a loss of length of the flap, which made it impossible to reach the lateral canthus.
DISCUSSION The current criterion standard for facial palsy surgical therapy relies on free muscle transfer. Nevertheless, local muscle flaps are an important resource that should be part of the surgeon’s
FIGURE 4. Detail of the artery and nerve intimate relationship at the main bifurcation. Their proximity is maintained until the last visible ramification at muscle edge.
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
631
Romeo et al
The Journal of Craniofacial Surgery
armamentarium. The first described use of local flaps in recent history goes back to 1907 with Lexer6 using the anterior edge of the masseter muscle to lift up the angle of the mouth. Since then, the anterior portion of the muscle has been used by many authors9,10 to lift the angle of the mouth alone or in combination with eye reanimation11 by splitting the muscle in 2 subunits. In more recent times, De Castro Correia and Zani7 reported the first nerve anatomic study to allow safe muscle splitting. Shinohara12 proposed an interesting alternative by splitting the upper portion of the muscle elongated with a strip of fascia lata using the zygomatic arch as a pulley to reach the angle of the mouth. Hwang et al1 was the first to describe the various patterns of distribution and depth of the nerve inside the muscle but did not mention the relationship with the vascular bundle as Hontanilla and Qiu13 did, describing a ‘‘treelike’’ distribution with no further specification or pattern description. In our study, the nerve main division always gives 2 branches in the upper portion of the middle third of the muscle; the recurrent branch to the posterior muscle subunit is discarded because of its variability, whereas the anterior branch is followed to raise the anterior third as innervated flap, thanks to its segmental neurovascular distribution. Our data confirm and merge the findings of Hontanilla and Qiu13 (nerve-artery relationship) and Hwang et al1 (defined pattern of distribution), implementing the previous studies describing a ‘‘comblike’’ distribution in the anterior third of the muscle. Once the flap is flipped upward, a fascial extension is needed to reach the eye canthus similar to the temporalis muscle flap. The angle formed by the masseter and the corner of the eye is similar to the one defined in the temporal muscle flap described by Salimbeni.14 This study provides more evidence of the close relationship of the masseteric nerve and artery and confirms the possibility of raising the anterior third of the muscle, thanks to its rich innervation, as a multipurpose flap for local use to reach the corner of the mouth or the eye canthus, although its shortness requires tendon or fascia extension to easily reach the latter. Using the gonion as landmark helps to quickly identify the areas free of relevant nerve/artery distribution.
FIGURE 5. The superficial layer of the muscle is removed to show the bundle distribution. The rectangular area on the right third of the image defines the anterior portion of the muscle that is used as local flap.
632
& Volume 25, Number 2, March 2014
FIGURE 6. The flap is raised from a fresh cadaver. The thin arrow indicates the master muscle; the short arrow points at the neurovascular pedicle entering the flap.
These findings provide relevant information to the surgeon for a safer and more advanced surgical approach to the lateral face district and facial reanimation.
ACKNOWLEDGMENTS The authors thank the donors of the human bodies that allowed the realization of the study.
REFERENCES 1. Hwang K, Kim YJ, Chung IH, et al. Course of the masseteric nerve in masseter muscle. J Craniofac Surg 2005;16:197Y200 2. Rohe JW, Yokochi C, Lutjen-Drecoll E. Color Atlas of Anatomy: A Photographic Study of the Human Body. 7th ed. Baltimore, MD: Lippincott Williams & Wilkins; 2007:56Y83 3. Houseman ND, Taylor GI, PanW-R. The angiosomes of the head and neck: anatomic study and clinical applications. Plast Reconstr Surg 105:2287Y2313 4. Arijj Y, Kimura Y, Gotoh M, et al. Blood flow in and around the masseter muscle: normal and pathologic features demonstrated by color Doppler sonography. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2001;91:472Y482 5. Hwang K, Kim YJ, Park H, et al. Selective neurectomy of the masseteric nerve in masseter hypertrophy. J Craniofac Surg 2004;15:780Y784 6. AlexanderRJ.Correction of facial paralysis by muscle transplant. Rocky Mt Med J 1941;38:713Y716 7. De Castro Correia P, Zani R.Masseter muscle rotation in the treatment of inferior facial paralysis. Anatomical and clinical observations. Plast Reconstr Surg 1973;52:370Y373 8. Shinohara H, Matsuo K, OsadaY, et al.Facial reanimation by transposition of the masseter muscle combined with tensor fascia lata, using the zygomatic arch as a pulley. Scand J Plast Reconstr Surg Hand Surg 2008;42:17Y22 9. Adson AW .Surgical treatment of facial paralysis. Arch Otolaryngol Head Neck Surg 1925;2:217Y249 10. Hastings S. Transplantation of anterior half of masseter muscle for facial paralysis. Proc R Soc Med 1920;13:64Y65 11. Halle M .The occurrence of facial paralysis and methods for its correction. Laryngoscope 1938;48:225Y235 12. Shinohara H, Matsuo K, Osada TY, et al Alternative facial reanimation by masseter muscle transposition combined with tensor fascia lata using the zygomatic arch as a pulley. Scand J Plast Reconstr Surg Hand Surg 2008;42:17Y22 13. Hontanilla B, Qiu SS. Transposition of the hemimasseteric muscle for dynamic rehabilitation of facial paralysis. J Craniofac Surg 2012;23:203Y205 14. Salimbeni G. Eyelid reanimation in facial paralysis by temporalis muscle transfer. Oper Tech Plast Reconstr Surg 1999;6:159Y162
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
