Discussion Discussion: The Surgical Correction of Pierre Robin Sequence: Mandibular Distraction Osteogenesis versus Tongue-Lip Adhesion Arun K. Gosain, M.D. Chicago, Ill.
T
he present study spans 15 of the first 16 years of the senior author’s (R.J.H.) professional career to address one of the most challenging patient populations in plastic surgery. One must assume that there was some evolution in technical performance of these procedures over this period. The most notable evolution in technical performance is that the senior author’s technique for treating patients with nonsyndromic Pierre Robin sequence changed from tongue-lip adhesion (from 1994 to 2004) to mandibular distraction osteotomy (from 2004 to 2009). The authors note that the study populations differed in that patients studied from 2004 to 2009 had a significantly greater preoperative apnea-hypopnea index than those studied from 1994 to 2004 (47 versus 37.6). This would suggest that the patients studied in the last 5 years had a more severe respiratory obstruction than those studied in the first 10 years. These observations lead to the following questions: (1) Why did patients presenting in the last 5 years of the study have more severe respiratory compromise on presentation? (2) Why was the rate of patient accrual so different in the last 5 years (4.8 patients per year) relative to the first 10 years (1.5 patients per year)? The authors also note that, of the 15 patients treated with t ongue-lip adhesion, three had wound dehiscence, three required scar revision because of lip scar contracture, and four required tracheostomy. However, the authors do not provide information as to whether any of these complications were related. Technical failure of tongue-lip adhesion (wound dehiscence) in the face of respiratory compromise will require another definitive procedure for management of respiratory compromise, whether it is mandibular distraction osteotomy, tongue-lip From the Division of Plastic Surgery, Lurie Children’s Hospital of Northwestern Feinberg School of Medicine. Received for publication November 24, 2013; accepted January 3, 2014. Copyright © 2014 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0000000000000183
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adhesion, or tracheostomy, and does not provide information as to the efficacy of any of the procedures. Although the authors attempt to focus on nonsyndromic patients with Pierre Robin sequence, one does not always know whether a patient is nonsyndromic when consulted to evaluate a neonate with airway compromise. Up to 20 percent of patients with Pierre Robin sequence may have Stickler syndrome; in addition, there are numerous chromosomal deletions in which the effects of the deletion on airway function are not known at the time of initial consultation. Although the present study excludes all patients with “an identifiable craniofacial syndrome,” future studies should investigate how each syndrome and/or chromosomal aberration might affect one’s treatment algorithm based on the associated anatomical findings and function. There are several important anatomical factors that determine the outcome of intervention in patients with Pierre Robin sequence. Whereas this and previous studies focus on the position of the tongue base, for each patient, one must understand the anatomy of the epiglottis, the supraglottic larynx, and the larynx and its interplay in airway function. Laryngomalacia refers to the circumstance in which the supraglottic larynx collapses on inspiration. The authors indicate that they considered this in their preoperative evaluation, but they do not indicate whether they responded to the information differently from 1994 to 2004 when they were performing tongue-lip adhesion or from 2004 to 2009 when they were performing mandibular distraction osteotomy. Furthermore, the most severely affected patients will be intubated on initial assessment, further complicating the assessment in patients who may not benefit from any procedure short of a tracheostomy (Fig. 1). Disclosure: The author has no financial interest to declare in relation to the content of this Discussion or of the associated article.
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Volume 133, Number 6 • Discussion
Fig. 1. Nasoendoscopic view of the base of the tongue in a neonate with nonsyndromic Pierre Robin sequence. (Left) The tongue-base (below) remains in contact with the posterior pharyngeal wall (above) during inspiration, thereby obstructing the airway and blocking visualization of the supraglottic larynx. (Right) After tongue-lip adhesion, the tongue base has been positioned forward, demonstrating laryngomalacia with collapse of the supraglottic larynx on inspiration.
In a recent study of 50 cases of mandibular distraction osteotomy in both syndromic and nonsyndromic patients with Pierre Robin sequence, the senior author found four cases in which mandibular distraction osteotomy failed, necessitating tracheostomy.1 Two of these patients had underlying laryngomalacia, reaffirming the difficulty in obtaining a clear preoperative diagnosis that may have altered surgical strategy. There may well be a subset of patients with abnormalities of the supraglottic larynx in which airway compromise is relieved with mandibular distraction osteotomy but not with tongue-lip adhesion. We have seen circumstances of tongue-based airway obstruction in which the supraglottic larynx does not collapse on inspiration but the epiglottis remains lax and tends to obstruct the supraglottic larynx even when the tongue is pulled forward with a laryngoscope. This appears to be because of laxity of the connecting ligaments between the tongue base and epiglottis, and in such cases mandibular distraction osteotomy may be more effective than tongue-lip adhesion because mandibular distraction osteotomy advances the mandible, tongue base, and floor of the mouth, thereby improving the tone of the ligaments between the tongue base and epiglottis and helping to upright the epiglottis. Clear definition of anatomy that favors one procedure over another warrants further study. To make an informed decision as to which form of intervention is most suitable, long-term
outcomes for both tongue-lip adhesion and mandibular distraction osteotomy must be investigated. Does tongue-lip adhesion compromise oromotor function later in life? The authors do not clarify (1) the duration of tongue-lip adhesion, (2) how the decision to take down the tongue-lip adhesion was made, or (3) the longterm oromotor function in these children. Are there objective data documenting long-term outcomes of mandibular distraction osteotomy? The authors state that, “Because of limitations in follow-up, loss to lower lip sensibility, damage to tooth buds, and hindrance to mandibular growth could not be recorded.” It is clear that our present level of knowledge with either tongue-lip adhesion or mandibular distraction osteotomy is not adequate for us to state that the long-term morbidity of one procedure is more or less significant, and future studies should recall both sets of patients to collect objective measures of these parameters. An additional question that is a key component of the outcome is the impact of gastroesophageal function on the outcome of intervention, and the return to oral feeding once the tongue-based airway obstruction is cleared. Although feeding was not evaluated in the present study, the senior author had previously reported that early intervention to improve gastroesophageal reflux disease should be considered to improve outcomes.1 It would make sense that gastroesophageal reflux disease must be addressed whether one elects to
1441
Plastic and Reconstructive Surgery • June 2014 perform tongue-lip adhesion or mandibular distraction osteotomy before an infant can achieve normal oral feeding. In summary, the present study provides valuable insight into the senior author’s experience with Pierre Robin sequence over 15 years. Most importantly, the study opens the door to further investigation so that more consistent protocols for the diagnosis and management of affected infants are developed based on the pathophysiology specific to each patient.
1442
Arun K. Gosain, M.D. Division of Plastic Surgery Lurie Children’s Hospital 225 East Chicago Avenue, Box 93 Chicago, Ill. 60611 [email protected]
REFERENCE 1. Murage KP, Tholpady SS, Friel M, Havlik RJ, Flores RL. Outcomes analysis of mandibular distraction osteogenesis for the treatment of Pierre Robin sequence. Plast Reconstr Surg. 2013;132:419–421.
T
he present study spans 15 of the first 16 years of the senior author’s (R.J.H.) professional career to address one of the most challenging patient populations in plastic surgery. One must assume that there was some evolution in technical performance of these procedures over this period. The most notable evolution in technical performance is that the senior author’s technique for treating patients with nonsyndromic Pierre Robin sequence changed from tongue-lip adhesion (from 1994 to 2004) to mandibular distraction osteotomy (from 2004 to 2009). The authors note that the study populations differed in that patients studied from 2004 to 2009 had a significantly greater preoperative apnea-hypopnea index than those studied from 1994 to 2004 (47 versus 37.6). This would suggest that the patients studied in the last 5 years had a more severe respiratory obstruction than those studied in the first 10 years. These observations lead to the following questions: (1) Why did patients presenting in the last 5 years of the study have more severe respiratory compromise on presentation? (2) Why was the rate of patient accrual so different in the last 5 years (4.8 patients per year) relative to the first 10 years (1.5 patients per year)? The authors also note that, of the 15 patients treated with t ongue-lip adhesion, three had wound dehiscence, three required scar revision because of lip scar contracture, and four required tracheostomy. However, the authors do not provide information as to whether any of these complications were related. Technical failure of tongue-lip adhesion (wound dehiscence) in the face of respiratory compromise will require another definitive procedure for management of respiratory compromise, whether it is mandibular distraction osteotomy, tongue-lip From the Division of Plastic Surgery, Lurie Children’s Hospital of Northwestern Feinberg School of Medicine. Received for publication November 24, 2013; accepted January 3, 2014. Copyright © 2014 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0000000000000183
1440
adhesion, or tracheostomy, and does not provide information as to the efficacy of any of the procedures. Although the authors attempt to focus on nonsyndromic patients with Pierre Robin sequence, one does not always know whether a patient is nonsyndromic when consulted to evaluate a neonate with airway compromise. Up to 20 percent of patients with Pierre Robin sequence may have Stickler syndrome; in addition, there are numerous chromosomal deletions in which the effects of the deletion on airway function are not known at the time of initial consultation. Although the present study excludes all patients with “an identifiable craniofacial syndrome,” future studies should investigate how each syndrome and/or chromosomal aberration might affect one’s treatment algorithm based on the associated anatomical findings and function. There are several important anatomical factors that determine the outcome of intervention in patients with Pierre Robin sequence. Whereas this and previous studies focus on the position of the tongue base, for each patient, one must understand the anatomy of the epiglottis, the supraglottic larynx, and the larynx and its interplay in airway function. Laryngomalacia refers to the circumstance in which the supraglottic larynx collapses on inspiration. The authors indicate that they considered this in their preoperative evaluation, but they do not indicate whether they responded to the information differently from 1994 to 2004 when they were performing tongue-lip adhesion or from 2004 to 2009 when they were performing mandibular distraction osteotomy. Furthermore, the most severely affected patients will be intubated on initial assessment, further complicating the assessment in patients who may not benefit from any procedure short of a tracheostomy (Fig. 1). Disclosure: The author has no financial interest to declare in relation to the content of this Discussion or of the associated article.
www.PRSJournal.com
Volume 133, Number 6 • Discussion
Fig. 1. Nasoendoscopic view of the base of the tongue in a neonate with nonsyndromic Pierre Robin sequence. (Left) The tongue-base (below) remains in contact with the posterior pharyngeal wall (above) during inspiration, thereby obstructing the airway and blocking visualization of the supraglottic larynx. (Right) After tongue-lip adhesion, the tongue base has been positioned forward, demonstrating laryngomalacia with collapse of the supraglottic larynx on inspiration.
In a recent study of 50 cases of mandibular distraction osteotomy in both syndromic and nonsyndromic patients with Pierre Robin sequence, the senior author found four cases in which mandibular distraction osteotomy failed, necessitating tracheostomy.1 Two of these patients had underlying laryngomalacia, reaffirming the difficulty in obtaining a clear preoperative diagnosis that may have altered surgical strategy. There may well be a subset of patients with abnormalities of the supraglottic larynx in which airway compromise is relieved with mandibular distraction osteotomy but not with tongue-lip adhesion. We have seen circumstances of tongue-based airway obstruction in which the supraglottic larynx does not collapse on inspiration but the epiglottis remains lax and tends to obstruct the supraglottic larynx even when the tongue is pulled forward with a laryngoscope. This appears to be because of laxity of the connecting ligaments between the tongue base and epiglottis, and in such cases mandibular distraction osteotomy may be more effective than tongue-lip adhesion because mandibular distraction osteotomy advances the mandible, tongue base, and floor of the mouth, thereby improving the tone of the ligaments between the tongue base and epiglottis and helping to upright the epiglottis. Clear definition of anatomy that favors one procedure over another warrants further study. To make an informed decision as to which form of intervention is most suitable, long-term
outcomes for both tongue-lip adhesion and mandibular distraction osteotomy must be investigated. Does tongue-lip adhesion compromise oromotor function later in life? The authors do not clarify (1) the duration of tongue-lip adhesion, (2) how the decision to take down the tongue-lip adhesion was made, or (3) the longterm oromotor function in these children. Are there objective data documenting long-term outcomes of mandibular distraction osteotomy? The authors state that, “Because of limitations in follow-up, loss to lower lip sensibility, damage to tooth buds, and hindrance to mandibular growth could not be recorded.” It is clear that our present level of knowledge with either tongue-lip adhesion or mandibular distraction osteotomy is not adequate for us to state that the long-term morbidity of one procedure is more or less significant, and future studies should recall both sets of patients to collect objective measures of these parameters. An additional question that is a key component of the outcome is the impact of gastroesophageal function on the outcome of intervention, and the return to oral feeding once the tongue-based airway obstruction is cleared. Although feeding was not evaluated in the present study, the senior author had previously reported that early intervention to improve gastroesophageal reflux disease should be considered to improve outcomes.1 It would make sense that gastroesophageal reflux disease must be addressed whether one elects to
1441
Plastic and Reconstructive Surgery • June 2014 perform tongue-lip adhesion or mandibular distraction osteotomy before an infant can achieve normal oral feeding. In summary, the present study provides valuable insight into the senior author’s experience with Pierre Robin sequence over 15 years. Most importantly, the study opens the door to further investigation so that more consistent protocols for the diagnosis and management of affected infants are developed based on the pathophysiology specific to each patient.
1442
Arun K. Gosain, M.D. Division of Plastic Surgery Lurie Children’s Hospital 225 East Chicago Avenue, Box 93 Chicago, Ill. 60611 [email protected]
REFERENCE 1. Murage KP, Tholpady SS, Friel M, Havlik RJ, Flores RL. Outcomes analysis of mandibular distraction osteogenesis for the treatment of Pierre Robin sequence. Plast Reconstr Surg. 2013;132:419–421.
