The Journal of Craniofacial Surgery • Volume 25, Number 5, September 2014
In general, there are many pathophysiologic processes that can lead to NPPE. Excessive inspiratory force is the main cause and was reported to reach as high as −100 mm Hg during upper airway obstruction. This excessive negative pressure is thought to cause disruption of the alveolar capillaries to cause pulmonary edema and, sometimes, alveolar hemorrhage.6 Moreover, this event leads to an increase in venous return and blood flow to the right heart. However, hyperadrenergic state induced by hypoxia can increase systemic vascular resistance, pulmonary vascular resistance, and pulmonary capillary pressure and subsequently increase afterload.1, 5 This combination causes an increase in pulmonary blood volume and pulmonary venous pressure and then an increase in hydrostatic pressure and edema formation.5, 7 Most of NPPEs arise immediately after relief of an airway obstruction; however, a delayed onset of up to 24 hours has been reported.4 The clinical signs of NPPE are typical. After recovery from airway obstruction, the patient presents tachypnea, dyspnea, and decreased SpO2 levels despite of supplying oxygen. In addition, tachycardia and hypertension also can arise because of increased sympathetic activity. We can hear rales and rhonchi on chest auscultation,8 and chest radiograph shows rapid bilateral changes consistent with pulmonary edema.9 All the treatments for NPPE are supportive treatments and are able to be executed by any surgeon. 1. 2. 3. 4. 5.
Maintenance of the airway Supplying oxygen Hemodynamic stability Positive pressure ventilation Diuretics and appropriate fluid therapy
Although active treatment using intubation and positive pressure is required for severe cases of hypoxia, the use of CPAP for the treatment of acute pulmonary edema and respiratory failure is generally broadly accepted. There have been reports of successful treatment using noninvasive CPAP via facial masks or a nasal cannula.10 In this case, after recovering from airway obstruction with soft positive pressure ventilation and lidocaine administration, the patient had a clear consciousness and was able to excrete the sputum. The possibility of pulmonary aspiration was considered to be low, so CPAP could be applied through a mask while maintaining spontaneous respiration with assisted oral suctioning of the pink frothy sputum. As a result of the parallel allopathic treatments, the sputum in the lungs was removed, and the respiration sounds became clean on the ausculation of the thorax. After such treatment, the patient completely recovered without other problems. In conclusion, the patients receiving orthognathic surgery are easily exposed to the risk of NPPE because of upper airway obstruction. This event can cause fatal outcomes if quick and accurate measures are not taken. So, careful observation of the patient and accurate knowledge are required to treat this malady when it does occur. Active, quick, and adequate measures must be taken to treat the complications of NPPE.
REFERENCES 1. Lang SA, Duncan PG, Shephard DA, et al. Pulmonary oedema associated with airway obstruction. Can J Anaesth 1990;37:210–218 2. Krodel DJ, Bittner EA, Abdulnour R, et al. Case scenario: acute postoperative negative pressure pulmonary edema Anesthesiology 2010;113:200–207 3. Halow KD, Ford EG. Pulmonary edema following post-operative laryngospasm: a case report and review of the literature. Am Surg 1993;59:443–447
Brief Clinical Studies
4. McConkey PP. Postobstructive pulmonary oedema—a case series and review. Anaesth Intensive Care 2000;28:72–76 5. Udeshi A, Cantie SM, Pierre E. Postobstructive pulmonary edema. J Crit Care 2010;25:538 e1–5 6. Hirano Y, Sugawara T, Sato Y, et al. Negative pressure pulmonary edema following foramen magnum decompression for Chiari malformation type I. Neurol Med Chir (Tokyo) 2008;48:137–139 7. Guffin TN, Har-el G, Sanders A, et al. Acute postobstructive pulmonary edema. Otolaryngol Head Neck Surg 1995;112:235–237 8. Van Kooy MA, Gargiulo RF. Postobstructive pulmonary edema. Am Fam Physician 2000;62:401–404 9. Cascade PN, Alexander GD, Mackie DS. Negative-pressure pulmonary edema after endotracheal intubation. Radiology 1993;186:671–375 10. Volpicelli G, Fogliati C, Radeschi G, et al. A case of unilateral re-expansion pulmonary oedema successfully treated with non-invasive continuous positive airway pressure. Eur J Emerg Med 2004;11:291–294
Inferior Alveolar Nerve Repositioning and Orthognathic Surgery Amin Rahpeyma,* Saeedeh Khajehahmadi, DDS† Background: Inferior alveolar nerve (IAN) repositioning is a wellknown technique in implant dentistry. This invaluable technique can be combined with orthognathic techniques to enhance the effect of orthognathic surgery in some selected cases. Materials and Methods: In a retrospective study, data were obtained from the archived files of Department of Oral and Maxillofacial Surgery, Mashhad University of Medical Sciences, Iran, from 2007 to 2012. Patients undergoing mandibular orthognathic surgery alone or in combination with maxillary surgery were searched. Cases with IAN repositioning were selected. Results: In this study, in 4% of orthognathic surgical procedures involving the mandibular bone, IAN repositioning was indicated. Genioplasty, body ostectomy, total mandibular subapical alveolar osteotomy, and inferior border osteotomy for correction of asymmetric mandibular excess in hemimandibular hyperplasia were in this list. Conclusion: In carefully selected orthognathic patients, IAN repositioning can enhance the effect of orthognathic surgery and should be considered in the treatment plan strategies as an option. From the *Oral and Maxillofacial Diseases Research Center and †Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran. Received January 28, 2014. Accepted for publication February 17, 2014. Address correspondence and reprint requests to Saeedeh Khajehahmadi, DDS, Dental Research Center, Faculty of Dentistry, Mashhad University of Medical Sciences, Vakilabad Blvd, Mashhad, P.O. Box: 91735-984, Iran; E-mail: [email protected] or [email protected] Supported by a grant from the Vice Chancellor of Research of Mashhad University of Medical Sciences. The authors report no conflicts of interest. Copyright © 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000945
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
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The Journal of Craniofacial Surgery • Volume 25, Number 5, September 2014
Brief Clinical Studies
Key Words: Inferior alveolar nerve repositioning, orthognathic surgery, genioplasty
I
nferior alveolar nerve (IAN) repositioning in implant dentistry is indicated when there is insufficient available bone between the inferior dental canal and the edentulous ridge crest in posterior mandible while there is sufficient interarch space.1,2 This invaluable technique can be combined with orthognathic techniques to enhance the effect of orthognathic surgery while the function of inferior alveolar neurovascular bundle is preserved.3 It has been recommended that, in genioplasty procedures, the level of sliding osteotomy should be at least 4 to 5 mm below the mental foramen.4,5 In a microgenic mandible, the mental foramen is unexpectedly nearer to the inferior border of the body.6 This will reduce the available bone for inferior border osteotomy unless nerve repositioning is applied. This procedure is also indicated in rectangular mandibular body ostectomy posterior to the mental foramen and mandibular total subapical surgery in the patients with long-rooted posterior teeth and insufficient space between the inferior dental canal and root apices.7,8
MATERIALS AND METHODS In a retrospective study, data were obtained from the archived files of the Department of Oral and Maxillofacial Surgery, Mashhad University of Medical Sciences, Iran, from 2007 to 2012. Patients with mandibular orthognathic surgery alone or in combination with maxillary surgery were selected. Cases undergoing IAN repositioning were recorded. If the incisive nerve was transected intentionally during the procedure, then the term “nerve transpositioning” was applied, and when this nerve was preserved and inferior alveolar neurovascular bundle was retracted laterally, then the term “nerve lateralization” was used (Fig. 1). All the patients with orthognathic surgery and IAN repositioning were recalled. Lower lip and chin sensation were evaluated at the recall visit by static light touch test with a cotton-tipped applicator and 2-point discrimination test with sharp calipers. Patients were asked to tell when they felt a light touch on their face and to point to the exact location. For the 2-point discrimination test, patients were asked to determine single
FIGURE 1. A schematic representation. A, Genioplasty with standard method results in a small inferior border segment. The IAN repositioning will increase the available bone; therefore, the esthetic effect of the procedure will be enhanced. B, Straight-cut body osteotomy combined with nerve transpositioning (with incisive nerve transection) or nerve lateralization. C, Total mandibular subapical alveolar osteotomy combined with the IAN transpositioning. The total alveolus is moved forward, deep bite is corrected, and vertical dimension of the occlusion is increased while the integrity of IAN is guaranteed.
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TABLE 1. Demographic Information of 8 Patients that IAN Repositioning Was Used to Enhance the Esthetic Effect of Orthognathic Surgery
Patients 1 2 3 4 5 6 7 8 9
Orthognathic Surgery Genioplasty alone Genioplasty + ramus C osteotomy BOS+G BOS + G + VRO + maxillary Le Fort I BOS BOS B. OS BSSO + TMAO BOS + G + VRO + maxillary Le Fort I + inferior border osteotomy
Orthodontic Tooth FollowPreparation Up, y
Lip Sensation (Last Visit)
Type of IAN Repositioning
No Yes
5 3
N N
NT NT
Yes No
2 3
N N
NT NT
Yes Yes Yes Yes No
4 3 2 1 1
N N N Incomplete N
NL NT NT NT
G, genioplasty; BOS, body ostectomy; VRO, vertical ramous osteotomy; N, normal; BSSO, bilateral sagittal split osteotomy; NL, nerve lateralization; NT, nerve transposition; TMAO, total mandibular subapical alveolar osteotomy.
and 2 points of touch. The results were compared with the upper lip skin as control.
RESULTS There were 235 patients undergoing orthognathic surgery from 2007 to 2012. There were 9 cases in which IAN repositioning and orthognathic surgery had been performed simultaneously and responded to recall (Table 1). Male-female ratio was 4:5 with an age range of 23 to 38 years. The distribution of surgical procedures was as follows: genioplasty alone in 1 patient, genioplasty and bilateral ramus C osteotomy for the correction of facial deformity after temporomandibular joint ankylosis release in another patient (Fig. 2), body ostectomy in 5 patients (Fig. 3), total mandibular subapical alveolar osteotomy in 1 patient accompanied with IAN repositioning (Fig. 4), and finally, inferior border osteotomy in asymmetric mandibular excess in 1 syndromic patient (Fig. 5). All the procedures for nerve repositioning had been performed bilaterally except for the case of hemimandibular hyperplasia. In the orthognathic cases, the most commonly used technique was nerve transpositioning (8 cases), and nerve lateralization had been used only in 1 patient with body ostectomy surgery. Genioplasty patients selected to have added IAN transpositioning all had unfavorable
FIGURE 2. The IAN transpositioning increased the available bone for genioplasty. A, Small distance between the mental foramen and inferior mandibular border. B, Ostectomy around the mental foramen. C, The other side. D, Genioplasty with a good bony base while the IAN is preserved.
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery • Volume 25, Number 5, September 2014
FIGURE 3. Genioplasty, mandibular body ostectomy, and mental nerve transpositioning.
position of the mental foramen (close to the inferior mandibular border). Straight-cut body osteotomy and total mandibular subapical alveolar osteotomy concomitant with IAN repositioning had been performed in the mandibles with insufficient space between tooth apices and the inferior dental canal. This information was obtained from preoperative panoramic radiographic views. Lower lip and chin sensation, tested by 2-point discrimination and static light touch tests, showed normal results, except for 1 patient.
DISCUSSION The IAN repositioning is a well-known procedure in implant dentistry. Nerve transpositioning will increase the available bone for osteotomy, and although nerve lateralization is a more biologic procedure, its use in mandibular orthognathic surgery is very limited. In nerve lateralization, the mental foramen position is fixed; therefore, in genioplasty alone or in genioplasty combined with other orthognathic procedures on the body of the mandible or ramus, the available bone at the chin area will not increase. The other reason is that IAN transpositioning is technically easier than nerve lateralization. In our series, nerve lateralization was indicated only in 1 patient with mandibular body ostectomy through the edentulous space in the first mandibular molar region. In the current study, in 4% of orthognathic surgical procedures involving the mandibular bone, IAN repositioning was indicated. There are some differences between this procedure in the edentulous region for the purpose of dental implant insertion and in dentate patients for orthognathic surgery. These differences are listed below: 1. There is an increased risk of injury to tooth roots during ostectomy procedures. 2. Difficulty of the procedure is increased because of the need for more delicate release of arterial and nerve branches to the mandibular teeth posterior to the mental foramen. 3. The patients in the orthognathic group are younger than the dental implant patients.
There are alternative ways for avoiding nerve repositioning in the body ostectomy and total mandibular subapical alveolar osteotomy. If there is sufficient bone between root apices in the posterior
FIGURE 4. Ostectomy around the mental foramen and lateral window preparation in a case of total mandibular subapical alveolar osteotomy.
Brief Clinical Studies
FIGURE 5. Inferior border osteotomy in correction of hemimandibular hyperplasia in the right side needs to reposition the IAN. Le Fort I osteotomy for the correction of occlusal cant and bone grafting, high condylectomy, bilateral ramus osteotomies, and genioplasty also were performed to correct deformity.
mandible and inferior dental canal, then stepped design in the former and straight osteotomy in this space (5 mm below the root apices) for the latter can be performed.9,10 In hemimandibular hyperplasia correction of the inferior border, excess is an integral part of the surgery. Nerve repositioning is an important step for preventing IAN injury during inferior border osteotomy.11,12 Whenever possible, these methods should be used, and IAN repositioning should be considered as the last resort for avoiding the morbidity of the inferior alveolar neurovascular bundle rather than as a routine procedure. In genioplasty, when the location of the mental foramen limits the available bone for lower border osteotomy, there remains no technique except for nerve transpositioning. Adding nerve repositioning to the orthognathic surgery in some selected cases is beneficial, but it has some drawbacks, such as increasing the operation time and raising the chance of abnormality in lip sensation, especially when these procedures are combined with other orthognathic surgeries in the mandibular bone, particularly with bilateral sagittal split osteotomy with its own potential of injury to the IAN and their cumulative effect in this regard.13,14 In our series, alteration in sensation of the lip and chin in the long-term follow-up was 11%. Transecting the incisive nerve and artery in nerve lateralization will reduce the blood supply to the mandible15; therefore, there is greater need for delicate surgery with more attention to soft tissue pedicles.
CONCLUSIONS In carefully selected orthognathic patients, IAN repositioning can enhance the effect of orthognathic surgery and should be considered in the treatment plan strategies as an option. ACKNOWLEDGMENT This study was supported by a grant from the Vice Chancellor of Research of Mashhad University of Medical Sciences.
REFERENCES 1. Khajehahmadi S, Rahpeyma A, Bidar M, et al. Vitality of intact teeth anterior to the mental foramen after inferior alveolar nerve repositioning: nerve transpositioning versus nerve lateralization. Int J Oral Maxillofac Surg 2013;42:1073–1078 2. Peleg M, Mazor Z, Chaushu G, et al. Lateralization of the inferior alveolar nerve with simultaneous implant placement: a modified technique. Int J Oral Maxillofac Implants 2002;17:101–106 3. Kahnberg KE, Ridell A. Transposition of the mental nerve in orthognathic surgery. J Oral Maxillofac Surg 1987;45:315–318 4. Hazani R, Rao A, Ford R, et al. The safe zone for placement of chin implants. Plast Reconstr Surg 2013;131:869–872 5. Ousterhout DK. Sliding genioplasty, avoiding mental nerve injuries. J Craniofac Surg 1996;7:297–298
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
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The Journal of Craniofacial Surgery • Volume 25, Number 5, September 2014
6. Hwang K, Lee WJ, Song YB, et al. Vulnerability of the inferior alveolar nerve and mental nerve during genioplasty: an anatomic study. J Craniofac Surg 2005;16:10–14 7. Sencimen M, Gulses A, Sabuncuoglu FA, et al. Rectangular body ostectomy for the treatment of severe mandibular prognathism. J Craniofac Surg 2012;23:e190–e193 8. Boye T, Doyle P, McKeown F, et al. Total subapical mandibular osteotomy to correct class 2 division 1 dento-facial deformity. J Craniomaxillofac Surg 2012;40:238–242 9. Keller EE, Gandy SR. Modified mandibular body step osteotomy-ostectomy. Int J Adult Orthodon Orthognath Surg 1993;8:37–45 10. MacIntosh R, Carlotti AE. Total mandibular alveolar osteotomy in the management of skeletal (infantile) apertognathia. J Oral Surg 1975;33:921–928 11. Ferguson JW. Definitive surgical correction of the deformity resulting from hemimandibular hyperplasia. J Craniomaxillofac Surg 2005;33:150–157 12. Blair AE, Schneider EK. Intraoral inferior border osteotomy for correction of mandibular asymmetry. J Oral Surg 1977a;35:493–496 13. Babbush CA. Transpositioning and repositioning the inferior alveolar and mental nerves in conjunction with endosteal implant reconstruction. Periodontol 2000 1998;17:183–190 14. Gianni AB, D'Orto O, Biglioli F, et al. Neurosensory alterations of the inferior alveolar and mental nerve after genioplasty alone or associated with sagittal osteotomy of the mandibular ramus. J Craniomaxillofac Surg 2002;30:295–303 15. Meyer MW, Cavanaugh GD. Blood flow changes after orthognathic surgery: maxillary and mandibular subapicalosteotomy. J Oral Surg 1976;34:495–501
nasopharynx; and acute infection. Nasal endoscopy was performed and evaluated adenoid size (choanal obstruction ratio) in all patients by an otorhinolaryngologist who was blinded to the information of other data. Lateral nasopharyngeal x-ray graphs of all patients were evaluated by pediatricians with adenoid-nasopharynx (A-N) ratio, who were blinded to the information of other data. The A-N ratio was calculated by Fujioka method. The A-N ratio of each patient was compared with the choanal obstruction ratio that was determined in the nasal endoscopic examination. Spearman correlation test was used for statistical analysis, and P < 0.05 was described as significant. Results: Forty-six patients were included in this study. The study sample consisted of 25 male (54.3%) and 21 female (45.7%) patients. The mean age of the patients was 6.17 years (range, 2–14 y). In the nasal endoscopic examination, the mean (SD) choanal obstruction ratio was 64.6% (19.5%) (range, 12.5%–90%). Mean (SD) A-N ratio was found to be 16.7 (14.4). The A-N ratio correlated with nasal endoscopic examination findings (r = 0.334, P = 0.023) Conclusions: The A-N ratio was found to be a useful, tolerable, and confident diagnostic method in pediatric patients for adenoid hypertrophy. Pediatricians can confidently use this method for decision after follow-up or operation. Key Words: Adenoid, pediatrician, nasopharyngeal graphs
T
Method of the Diagnosis of Adenoid Hypertrophy for Physicians: Adenoid-Nasopharynx Ratio Mehtap Acar, MD,* Ekrem Said Kankilic, MD,† Ali Osman Koksal, MD,‡ Aslihan Arasli Yilmaz, MD,‡ Deniz Kocaoz, MD† Objective: We aimed to describe the feasibility of a prediction of adenoid hypertrophy by pediatricians for diagnostic accuracy of nasopharyngeal x-ray in a pediatric unit. Methods: Forty-six patients with a history of probable adenoid hypertrophy between January 2013 and August 2013 were included in the study. Participants were excluded from the study if they had previous adenoidectomy; anatomic anomaly in the nose, palate, or
From the *Dr. Sami Ulus Children Hospital; Departments of †Otorhinolaryngology and ‡Pediatrics, Kecioren Training and Research Hospital, Ankara, Turkey. Received January 8, 2014. Accepted for publication February 17, 2014. Address correspondence and reprint requests to Mehtap Acar, MD, Dr. Sami Ulus Childrens Hospital, Yıldırım mh., Babür cd., No: 44 Altındağ 06080, Ankara, Turkey; 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.0000000000000952
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he adenoid or nasopharyngeal tonsil is located above the tonsils, in the roof of the nasopharynx. The adenoids are part of our lymphoepithelial system; they play a protective role in disease of the upper respiratory tract.1 The adenotonsillar hypertrophy is an unusual growth of the Waldeyer ring that is located in the nasopharyngeal area, resulting from frequent infectious and obstructive causes. The diagnosis of adenoid hypertrophy has increased rapidly since the introduction of the adenoid vegetation term by Meyer in 1868.2 The diagnosis of adenoid hypertrophy has become a challenge in this period. There are various methods for the diagnosis of adenoid hypertrophy that include lateral neck x-ray, videofluoroscopy, palpation, and nasal endoscopy.3,4 The standard diagnostic criteria can only be indicative, and the diagnosis is made via transnasal endoscopy confirmed by an otolaryngologist. The modalities of lateral nasopharyngeal x-ray are a controversial issue.5 Numerous different x-ray measurements were performed to validate the reliability of this morphometric analysis for functional interpretation in different studies conducted by different authors. Adenoidal-nasopharyngeal (A-N) ratio was originally developed by Fujioka et al6 (Fig. 1), with the emphasis on applications correlated to adenoidal size and clinical symptoms.
FIGURE 1. An image showing the A-N ratio figure.
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
In general, there are many pathophysiologic processes that can lead to NPPE. Excessive inspiratory force is the main cause and was reported to reach as high as −100 mm Hg during upper airway obstruction. This excessive negative pressure is thought to cause disruption of the alveolar capillaries to cause pulmonary edema and, sometimes, alveolar hemorrhage.6 Moreover, this event leads to an increase in venous return and blood flow to the right heart. However, hyperadrenergic state induced by hypoxia can increase systemic vascular resistance, pulmonary vascular resistance, and pulmonary capillary pressure and subsequently increase afterload.1, 5 This combination causes an increase in pulmonary blood volume and pulmonary venous pressure and then an increase in hydrostatic pressure and edema formation.5, 7 Most of NPPEs arise immediately after relief of an airway obstruction; however, a delayed onset of up to 24 hours has been reported.4 The clinical signs of NPPE are typical. After recovery from airway obstruction, the patient presents tachypnea, dyspnea, and decreased SpO2 levels despite of supplying oxygen. In addition, tachycardia and hypertension also can arise because of increased sympathetic activity. We can hear rales and rhonchi on chest auscultation,8 and chest radiograph shows rapid bilateral changes consistent with pulmonary edema.9 All the treatments for NPPE are supportive treatments and are able to be executed by any surgeon. 1. 2. 3. 4. 5.
Maintenance of the airway Supplying oxygen Hemodynamic stability Positive pressure ventilation Diuretics and appropriate fluid therapy
Although active treatment using intubation and positive pressure is required for severe cases of hypoxia, the use of CPAP for the treatment of acute pulmonary edema and respiratory failure is generally broadly accepted. There have been reports of successful treatment using noninvasive CPAP via facial masks or a nasal cannula.10 In this case, after recovering from airway obstruction with soft positive pressure ventilation and lidocaine administration, the patient had a clear consciousness and was able to excrete the sputum. The possibility of pulmonary aspiration was considered to be low, so CPAP could be applied through a mask while maintaining spontaneous respiration with assisted oral suctioning of the pink frothy sputum. As a result of the parallel allopathic treatments, the sputum in the lungs was removed, and the respiration sounds became clean on the ausculation of the thorax. After such treatment, the patient completely recovered without other problems. In conclusion, the patients receiving orthognathic surgery are easily exposed to the risk of NPPE because of upper airway obstruction. This event can cause fatal outcomes if quick and accurate measures are not taken. So, careful observation of the patient and accurate knowledge are required to treat this malady when it does occur. Active, quick, and adequate measures must be taken to treat the complications of NPPE.
REFERENCES 1. Lang SA, Duncan PG, Shephard DA, et al. Pulmonary oedema associated with airway obstruction. Can J Anaesth 1990;37:210–218 2. Krodel DJ, Bittner EA, Abdulnour R, et al. Case scenario: acute postoperative negative pressure pulmonary edema Anesthesiology 2010;113:200–207 3. Halow KD, Ford EG. Pulmonary edema following post-operative laryngospasm: a case report and review of the literature. Am Surg 1993;59:443–447
Brief Clinical Studies
4. McConkey PP. Postobstructive pulmonary oedema—a case series and review. Anaesth Intensive Care 2000;28:72–76 5. Udeshi A, Cantie SM, Pierre E. Postobstructive pulmonary edema. J Crit Care 2010;25:538 e1–5 6. Hirano Y, Sugawara T, Sato Y, et al. Negative pressure pulmonary edema following foramen magnum decompression for Chiari malformation type I. Neurol Med Chir (Tokyo) 2008;48:137–139 7. Guffin TN, Har-el G, Sanders A, et al. Acute postobstructive pulmonary edema. Otolaryngol Head Neck Surg 1995;112:235–237 8. Van Kooy MA, Gargiulo RF. Postobstructive pulmonary edema. Am Fam Physician 2000;62:401–404 9. Cascade PN, Alexander GD, Mackie DS. Negative-pressure pulmonary edema after endotracheal intubation. Radiology 1993;186:671–375 10. Volpicelli G, Fogliati C, Radeschi G, et al. A case of unilateral re-expansion pulmonary oedema successfully treated with non-invasive continuous positive airway pressure. Eur J Emerg Med 2004;11:291–294
Inferior Alveolar Nerve Repositioning and Orthognathic Surgery Amin Rahpeyma,* Saeedeh Khajehahmadi, DDS† Background: Inferior alveolar nerve (IAN) repositioning is a wellknown technique in implant dentistry. This invaluable technique can be combined with orthognathic techniques to enhance the effect of orthognathic surgery in some selected cases. Materials and Methods: In a retrospective study, data were obtained from the archived files of Department of Oral and Maxillofacial Surgery, Mashhad University of Medical Sciences, Iran, from 2007 to 2012. Patients undergoing mandibular orthognathic surgery alone or in combination with maxillary surgery were searched. Cases with IAN repositioning were selected. Results: In this study, in 4% of orthognathic surgical procedures involving the mandibular bone, IAN repositioning was indicated. Genioplasty, body ostectomy, total mandibular subapical alveolar osteotomy, and inferior border osteotomy for correction of asymmetric mandibular excess in hemimandibular hyperplasia were in this list. Conclusion: In carefully selected orthognathic patients, IAN repositioning can enhance the effect of orthognathic surgery and should be considered in the treatment plan strategies as an option. From the *Oral and Maxillofacial Diseases Research Center and †Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran. Received January 28, 2014. Accepted for publication February 17, 2014. Address correspondence and reprint requests to Saeedeh Khajehahmadi, DDS, Dental Research Center, Faculty of Dentistry, Mashhad University of Medical Sciences, Vakilabad Blvd, Mashhad, P.O. Box: 91735-984, Iran; E-mail: [email protected] or [email protected] Supported by a grant from the Vice Chancellor of Research of Mashhad University of Medical Sciences. The authors report no conflicts of interest. Copyright © 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000945
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
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The Journal of Craniofacial Surgery • Volume 25, Number 5, September 2014
Brief Clinical Studies
Key Words: Inferior alveolar nerve repositioning, orthognathic surgery, genioplasty
I
nferior alveolar nerve (IAN) repositioning in implant dentistry is indicated when there is insufficient available bone between the inferior dental canal and the edentulous ridge crest in posterior mandible while there is sufficient interarch space.1,2 This invaluable technique can be combined with orthognathic techniques to enhance the effect of orthognathic surgery while the function of inferior alveolar neurovascular bundle is preserved.3 It has been recommended that, in genioplasty procedures, the level of sliding osteotomy should be at least 4 to 5 mm below the mental foramen.4,5 In a microgenic mandible, the mental foramen is unexpectedly nearer to the inferior border of the body.6 This will reduce the available bone for inferior border osteotomy unless nerve repositioning is applied. This procedure is also indicated in rectangular mandibular body ostectomy posterior to the mental foramen and mandibular total subapical surgery in the patients with long-rooted posterior teeth and insufficient space between the inferior dental canal and root apices.7,8
MATERIALS AND METHODS In a retrospective study, data were obtained from the archived files of the Department of Oral and Maxillofacial Surgery, Mashhad University of Medical Sciences, Iran, from 2007 to 2012. Patients with mandibular orthognathic surgery alone or in combination with maxillary surgery were selected. Cases undergoing IAN repositioning were recorded. If the incisive nerve was transected intentionally during the procedure, then the term “nerve transpositioning” was applied, and when this nerve was preserved and inferior alveolar neurovascular bundle was retracted laterally, then the term “nerve lateralization” was used (Fig. 1). All the patients with orthognathic surgery and IAN repositioning were recalled. Lower lip and chin sensation were evaluated at the recall visit by static light touch test with a cotton-tipped applicator and 2-point discrimination test with sharp calipers. Patients were asked to tell when they felt a light touch on their face and to point to the exact location. For the 2-point discrimination test, patients were asked to determine single
FIGURE 1. A schematic representation. A, Genioplasty with standard method results in a small inferior border segment. The IAN repositioning will increase the available bone; therefore, the esthetic effect of the procedure will be enhanced. B, Straight-cut body osteotomy combined with nerve transpositioning (with incisive nerve transection) or nerve lateralization. C, Total mandibular subapical alveolar osteotomy combined with the IAN transpositioning. The total alveolus is moved forward, deep bite is corrected, and vertical dimension of the occlusion is increased while the integrity of IAN is guaranteed.
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TABLE 1. Demographic Information of 8 Patients that IAN Repositioning Was Used to Enhance the Esthetic Effect of Orthognathic Surgery
Patients 1 2 3 4 5 6 7 8 9
Orthognathic Surgery Genioplasty alone Genioplasty + ramus C osteotomy BOS+G BOS + G + VRO + maxillary Le Fort I BOS BOS B. OS BSSO + TMAO BOS + G + VRO + maxillary Le Fort I + inferior border osteotomy
Orthodontic Tooth FollowPreparation Up, y
Lip Sensation (Last Visit)
Type of IAN Repositioning
No Yes
5 3
N N
NT NT
Yes No
2 3
N N
NT NT
Yes Yes Yes Yes No
4 3 2 1 1
N N N Incomplete N
NL NT NT NT
G, genioplasty; BOS, body ostectomy; VRO, vertical ramous osteotomy; N, normal; BSSO, bilateral sagittal split osteotomy; NL, nerve lateralization; NT, nerve transposition; TMAO, total mandibular subapical alveolar osteotomy.
and 2 points of touch. The results were compared with the upper lip skin as control.
RESULTS There were 235 patients undergoing orthognathic surgery from 2007 to 2012. There were 9 cases in which IAN repositioning and orthognathic surgery had been performed simultaneously and responded to recall (Table 1). Male-female ratio was 4:5 with an age range of 23 to 38 years. The distribution of surgical procedures was as follows: genioplasty alone in 1 patient, genioplasty and bilateral ramus C osteotomy for the correction of facial deformity after temporomandibular joint ankylosis release in another patient (Fig. 2), body ostectomy in 5 patients (Fig. 3), total mandibular subapical alveolar osteotomy in 1 patient accompanied with IAN repositioning (Fig. 4), and finally, inferior border osteotomy in asymmetric mandibular excess in 1 syndromic patient (Fig. 5). All the procedures for nerve repositioning had been performed bilaterally except for the case of hemimandibular hyperplasia. In the orthognathic cases, the most commonly used technique was nerve transpositioning (8 cases), and nerve lateralization had been used only in 1 patient with body ostectomy surgery. Genioplasty patients selected to have added IAN transpositioning all had unfavorable
FIGURE 2. The IAN transpositioning increased the available bone for genioplasty. A, Small distance between the mental foramen and inferior mandibular border. B, Ostectomy around the mental foramen. C, The other side. D, Genioplasty with a good bony base while the IAN is preserved.
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery • Volume 25, Number 5, September 2014
FIGURE 3. Genioplasty, mandibular body ostectomy, and mental nerve transpositioning.
position of the mental foramen (close to the inferior mandibular border). Straight-cut body osteotomy and total mandibular subapical alveolar osteotomy concomitant with IAN repositioning had been performed in the mandibles with insufficient space between tooth apices and the inferior dental canal. This information was obtained from preoperative panoramic radiographic views. Lower lip and chin sensation, tested by 2-point discrimination and static light touch tests, showed normal results, except for 1 patient.
DISCUSSION The IAN repositioning is a well-known procedure in implant dentistry. Nerve transpositioning will increase the available bone for osteotomy, and although nerve lateralization is a more biologic procedure, its use in mandibular orthognathic surgery is very limited. In nerve lateralization, the mental foramen position is fixed; therefore, in genioplasty alone or in genioplasty combined with other orthognathic procedures on the body of the mandible or ramus, the available bone at the chin area will not increase. The other reason is that IAN transpositioning is technically easier than nerve lateralization. In our series, nerve lateralization was indicated only in 1 patient with mandibular body ostectomy through the edentulous space in the first mandibular molar region. In the current study, in 4% of orthognathic surgical procedures involving the mandibular bone, IAN repositioning was indicated. There are some differences between this procedure in the edentulous region for the purpose of dental implant insertion and in dentate patients for orthognathic surgery. These differences are listed below: 1. There is an increased risk of injury to tooth roots during ostectomy procedures. 2. Difficulty of the procedure is increased because of the need for more delicate release of arterial and nerve branches to the mandibular teeth posterior to the mental foramen. 3. The patients in the orthognathic group are younger than the dental implant patients.
There are alternative ways for avoiding nerve repositioning in the body ostectomy and total mandibular subapical alveolar osteotomy. If there is sufficient bone between root apices in the posterior
FIGURE 4. Ostectomy around the mental foramen and lateral window preparation in a case of total mandibular subapical alveolar osteotomy.
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FIGURE 5. Inferior border osteotomy in correction of hemimandibular hyperplasia in the right side needs to reposition the IAN. Le Fort I osteotomy for the correction of occlusal cant and bone grafting, high condylectomy, bilateral ramus osteotomies, and genioplasty also were performed to correct deformity.
mandible and inferior dental canal, then stepped design in the former and straight osteotomy in this space (5 mm below the root apices) for the latter can be performed.9,10 In hemimandibular hyperplasia correction of the inferior border, excess is an integral part of the surgery. Nerve repositioning is an important step for preventing IAN injury during inferior border osteotomy.11,12 Whenever possible, these methods should be used, and IAN repositioning should be considered as the last resort for avoiding the morbidity of the inferior alveolar neurovascular bundle rather than as a routine procedure. In genioplasty, when the location of the mental foramen limits the available bone for lower border osteotomy, there remains no technique except for nerve transpositioning. Adding nerve repositioning to the orthognathic surgery in some selected cases is beneficial, but it has some drawbacks, such as increasing the operation time and raising the chance of abnormality in lip sensation, especially when these procedures are combined with other orthognathic surgeries in the mandibular bone, particularly with bilateral sagittal split osteotomy with its own potential of injury to the IAN and their cumulative effect in this regard.13,14 In our series, alteration in sensation of the lip and chin in the long-term follow-up was 11%. Transecting the incisive nerve and artery in nerve lateralization will reduce the blood supply to the mandible15; therefore, there is greater need for delicate surgery with more attention to soft tissue pedicles.
CONCLUSIONS In carefully selected orthognathic patients, IAN repositioning can enhance the effect of orthognathic surgery and should be considered in the treatment plan strategies as an option. ACKNOWLEDGMENT This study was supported by a grant from the Vice Chancellor of Research of Mashhad University of Medical Sciences.
REFERENCES 1. Khajehahmadi S, Rahpeyma A, Bidar M, et al. Vitality of intact teeth anterior to the mental foramen after inferior alveolar nerve repositioning: nerve transpositioning versus nerve lateralization. Int J Oral Maxillofac Surg 2013;42:1073–1078 2. Peleg M, Mazor Z, Chaushu G, et al. Lateralization of the inferior alveolar nerve with simultaneous implant placement: a modified technique. Int J Oral Maxillofac Implants 2002;17:101–106 3. Kahnberg KE, Ridell A. Transposition of the mental nerve in orthognathic surgery. J Oral Maxillofac Surg 1987;45:315–318 4. Hazani R, Rao A, Ford R, et al. The safe zone for placement of chin implants. Plast Reconstr Surg 2013;131:869–872 5. Ousterhout DK. Sliding genioplasty, avoiding mental nerve injuries. J Craniofac Surg 1996;7:297–298
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6. Hwang K, Lee WJ, Song YB, et al. Vulnerability of the inferior alveolar nerve and mental nerve during genioplasty: an anatomic study. J Craniofac Surg 2005;16:10–14 7. Sencimen M, Gulses A, Sabuncuoglu FA, et al. Rectangular body ostectomy for the treatment of severe mandibular prognathism. J Craniofac Surg 2012;23:e190–e193 8. Boye T, Doyle P, McKeown F, et al. Total subapical mandibular osteotomy to correct class 2 division 1 dento-facial deformity. J Craniomaxillofac Surg 2012;40:238–242 9. Keller EE, Gandy SR. Modified mandibular body step osteotomy-ostectomy. Int J Adult Orthodon Orthognath Surg 1993;8:37–45 10. MacIntosh R, Carlotti AE. Total mandibular alveolar osteotomy in the management of skeletal (infantile) apertognathia. J Oral Surg 1975;33:921–928 11. Ferguson JW. Definitive surgical correction of the deformity resulting from hemimandibular hyperplasia. J Craniomaxillofac Surg 2005;33:150–157 12. Blair AE, Schneider EK. Intraoral inferior border osteotomy for correction of mandibular asymmetry. J Oral Surg 1977a;35:493–496 13. Babbush CA. Transpositioning and repositioning the inferior alveolar and mental nerves in conjunction with endosteal implant reconstruction. Periodontol 2000 1998;17:183–190 14. Gianni AB, D'Orto O, Biglioli F, et al. Neurosensory alterations of the inferior alveolar and mental nerve after genioplasty alone or associated with sagittal osteotomy of the mandibular ramus. J Craniomaxillofac Surg 2002;30:295–303 15. Meyer MW, Cavanaugh GD. Blood flow changes after orthognathic surgery: maxillary and mandibular subapicalosteotomy. J Oral Surg 1976;34:495–501
nasopharynx; and acute infection. Nasal endoscopy was performed and evaluated adenoid size (choanal obstruction ratio) in all patients by an otorhinolaryngologist who was blinded to the information of other data. Lateral nasopharyngeal x-ray graphs of all patients were evaluated by pediatricians with adenoid-nasopharynx (A-N) ratio, who were blinded to the information of other data. The A-N ratio was calculated by Fujioka method. The A-N ratio of each patient was compared with the choanal obstruction ratio that was determined in the nasal endoscopic examination. Spearman correlation test was used for statistical analysis, and P < 0.05 was described as significant. Results: Forty-six patients were included in this study. The study sample consisted of 25 male (54.3%) and 21 female (45.7%) patients. The mean age of the patients was 6.17 years (range, 2–14 y). In the nasal endoscopic examination, the mean (SD) choanal obstruction ratio was 64.6% (19.5%) (range, 12.5%–90%). Mean (SD) A-N ratio was found to be 16.7 (14.4). The A-N ratio correlated with nasal endoscopic examination findings (r = 0.334, P = 0.023) Conclusions: The A-N ratio was found to be a useful, tolerable, and confident diagnostic method in pediatric patients for adenoid hypertrophy. Pediatricians can confidently use this method for decision after follow-up or operation. Key Words: Adenoid, pediatrician, nasopharyngeal graphs
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Method of the Diagnosis of Adenoid Hypertrophy for Physicians: Adenoid-Nasopharynx Ratio Mehtap Acar, MD,* Ekrem Said Kankilic, MD,† Ali Osman Koksal, MD,‡ Aslihan Arasli Yilmaz, MD,‡ Deniz Kocaoz, MD† Objective: We aimed to describe the feasibility of a prediction of adenoid hypertrophy by pediatricians for diagnostic accuracy of nasopharyngeal x-ray in a pediatric unit. Methods: Forty-six patients with a history of probable adenoid hypertrophy between January 2013 and August 2013 were included in the study. Participants were excluded from the study if they had previous adenoidectomy; anatomic anomaly in the nose, palate, or
From the *Dr. Sami Ulus Children Hospital; Departments of †Otorhinolaryngology and ‡Pediatrics, Kecioren Training and Research Hospital, Ankara, Turkey. Received January 8, 2014. Accepted for publication February 17, 2014. Address correspondence and reprint requests to Mehtap Acar, MD, Dr. Sami Ulus Childrens Hospital, Yıldırım mh., Babür cd., No: 44 Altındağ 06080, Ankara, Turkey; 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.0000000000000952
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he adenoid or nasopharyngeal tonsil is located above the tonsils, in the roof of the nasopharynx. The adenoids are part of our lymphoepithelial system; they play a protective role in disease of the upper respiratory tract.1 The adenotonsillar hypertrophy is an unusual growth of the Waldeyer ring that is located in the nasopharyngeal area, resulting from frequent infectious and obstructive causes. The diagnosis of adenoid hypertrophy has increased rapidly since the introduction of the adenoid vegetation term by Meyer in 1868.2 The diagnosis of adenoid hypertrophy has become a challenge in this period. There are various methods for the diagnosis of adenoid hypertrophy that include lateral neck x-ray, videofluoroscopy, palpation, and nasal endoscopy.3,4 The standard diagnostic criteria can only be indicative, and the diagnosis is made via transnasal endoscopy confirmed by an otolaryngologist. The modalities of lateral nasopharyngeal x-ray are a controversial issue.5 Numerous different x-ray measurements were performed to validate the reliability of this morphometric analysis for functional interpretation in different studies conducted by different authors. Adenoidal-nasopharyngeal (A-N) ratio was originally developed by Fujioka et al6 (Fig. 1), with the emphasis on applications correlated to adenoidal size and clinical symptoms.
FIGURE 1. An image showing the A-N ratio figure.
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
