- Email: [email protected]
Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy
YIJOM-3534; No of Pages 5
Int. J. Oral Maxillofac. Surg. 2016; xxx: xxx–xxx http://dx.doi.org/10.1016/j.ijom.2016.10.007, available online at http://www.sciencedirect.com
Clinical Paper Orthognathic Surgery
Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy
¨ .Koc¸2, K. Deniz1, S. S. Akdeniz1, A. O S. Uc¸kan1, L. N. Ozluog˘lu2 1
Department of Oral and Maxillofacial Surgery, Baskent University School of Dentistry, Ankara, Turkey; 2Department of Otorhinolaryngology, Baskent University School of Medicine, Ankara, Turkey
¨ . Koc¸, S. Uc¸kan, L. N. Ozluog˘lu: Evaluation of benign K. Deniz, S. S. Akdeniz, A. O paroxysmal positional vertigo following Le Fort I osteotomy. Int. J. Oral Maxillofac. Surg. 2016; xxx: xxx–xxx. # 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Abstract. The Le Fort I osteotomy is widely used to correct dentofacial deformities. Benign paroxysmal positional vertigo (BPPV) is a common vestibular end organ disorder characterized by short, often recurrent episodes of vertigo. Head trauma is one of the known causes of BPPV. During pterygoid osteotomy, the surgical trauma induced by percussion with the surgical mallet and osteotomes can displace otoliths into the semicircular canal, resulting in BPPV. The aim of this study was to evaluate the potential risk of occurrence of BPPV in individuals undergoing Le Fort I osteotomy. Twenty-three patients were included in this study. The Dix–Hallpike manoeuvre, positional tests using electronystagmography, and vestibular evoked myogenic potential (VEMP) tests were performed 1 week before surgery (T0), 1 week after surgery (T1), and 1 month after surgery (T2). The results were compared statistically. BPPV was observed in three patients. Eleven patients had nystagmus at the T1 evaluation and seven at the T2 evaluation. The difference between the T0 and T1 time points was statistically significant (P = 0.001). BPPV is a possible complication of Le Fort I osteotomy. Surgeons should be aware of this complication, and the diagnosis of BPPV should be considered in patients who have undergone Le Fort I osteotomy.
Patients with dentofacial deformities, such as congenital and acquired abnormal positioning of the maxilla, mandible, or both, can experience problems with facial aesthetics, mastication, and speech. The correction of midfacial deformities often involves Le Fort I osteotomy with advancement, impaction, or a combination of these movements. The Le Fort I osteotomy involves surgical trauma induced by percussion with 0901-5027/000001+05
the surgical mallet and osteotomes, along with hyperextension of the neck. It has been shown that this surgical trauma can promote different types of ear problems, such as decreased hearing sensitivity, middle ear pressure, and auditory function, because of the close relationship between the ear and the sphenoid bone.1–3 Benign paroxysmal positional vertigo (BPPV) is a common vestibular end organ disorder characterized by short, often
Key words: benign paroxysmal positional vertigo; Le Fort I; orthognathic surgery; vertigo. Accepted for publication 18 October 2016
recurrent, episodes of vertigo that are triggered by certain head movements in the plane of the semicircular canals. BPPV occurs in 15–20% of head trauma cases and is rarely reported after maxillofacial surgery. There are two pathophysiological mechanisms in BPPV: cupulolithiasis and canalithiasis. In cupulolithiasis, otoconial debris in the semicircular canal becomes attached to the cupula and the
# 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
YIJOM-3534; No of Pages 5
2
Deniz et al.
patient is rendered sensitive to gravity. In canalithiasis, calcium crystals, called otoliths, dislodge from the utricle of the inner ear and move within the lumen of the semicircular canals. When these otoliths move within the canal, they cause endolymph motion during the angular acceleration of the head that stimulates the affected canal, thereby causing vertigo. There are a few case reports and case series published in the literature concerning BPPV after dental and maxillofacial surgical procedures, such as impacted third molar removal, osteotome techniques for sinus floor elevation, alveolar augmentation by ridge splitting, and septorhinoplasty.4–7 There is only one clinical study suggesting that BPPV should be considered in patients who have undergone Le Fort I osteotomy,8 and knowledge about this complication following orthognathic surgery is still limited. The aims of this prospective study were to comprehensively evaluate the potential risk of occurrence of BPPV in individuals undergoing Le Fort I osteotomy and to compare the results of maxillary advancement and/or impaction procedures. Patients and methods
This study was approved by the institutional review board and ethics committee of the university. Written informed consent was obtained from all subjects. This prospective study was conducted between December 2011 and December 2014 in the department of oral and maxillofacial surgery of a university hospital in Istanbul, Turkey. A total of 23 consecutive patients (12 female and 11 male), ranging in age from 18 to 32 years, were included. All of the patients included were ASA I status according to the American Society of Anesthesiology (ASA) health status classification. Nasotracheal intubations were performed by the same anaesthesiologist using the same agent. The study patients underwent conventional Le Fort I osteotomy, and the pterygomaxillary dysjunction was performed with a reciprocating saw and curved osteotomes by the same surgical team. Postsurgical medication was standard for all subjects. Exclusion criteria were listed as having had a previous ear operation or ear anomaly, a history of BPPV, neurological disorders, orthognathic surgery, maxillofacial deformity, and failure to attend postoperative evaluation appointments. Electronystagmography (ENG) with the Dix–Hallpike manoeuvre, positional tests, and vestibular evoked myogenic potential (VEMP) tests were performed 1 week
before surgery (T0), 1 week after surgery (T1), and 1 month after surgery (T2) in the department of otorhinolaryngology, division of neuro-otology of the study university. All test results were evaluated by the senior author of this paper from the neurootology department (L.N.O.), who was blinded to the patient identities. The surgical procedure used was Le Fort I osteotomy with advancement (n = 11) or a combination of advancement and impaction (n = 12), with or without mandibular surgeries. For the Dix–Hallpike manoeuvre, the patient was asked to sit down, with the head turned approximately 458 to the right or left. The patient was then instructed to lie down in the dorsal decubitus position with the examiner holding their head. The head was kept at an approximately 308 extension. The diagnostic criteria included vertigo and the occurrence of characteristic mixed torsional and vertical nystagmus with the upper pole of the eye beating towards the dependent ear and vertical nystagmus beating towards the forehead. For the positional test, the patient was asked to lie down in the dorsal decubitus position with the head flexed anteriorly by 308. The patient was then instructed to turn the head to one side and keep it in that position for up to 1 min. The diagnostic criteria included provoked vertigo and horizontal nystagmus. The VEMP test was performed with the patient in a sitting position with his or her chin turned over the contralateral shoulder, tensing the sternocleidomastoid muscle (SCM). Surface electromyographic activity was recorded with an evoked acoustic potential system (VEMP System, Eclipse preamplifier EPA 4V, Smart EP 15; Interacoustics a/s, Assens, Denmark). Active non-inverting recording electrodes were placed in the middle third part of the SCM. Reference electrodes were placed ipsilateral to the sternal manubrium region near the tendon of the SCM and a ground electrode was placed in the centre of the forehead. The VEMP responses were obtained by binaural acoustic stimulation and recorded from bilateral SCMs. Tone bursts at 500 Hz were delivered through an inserted earphone at a rate of 5.1/s for an average of 200 repetitions (500 Hz, 120 dB SPL hearing level intensity, stimulation rate 5.1/s). Electromyographic signals were amplified and band-pass filtered (range 10–1500 Hz). Electromyographic signals were recorded for 50 ms. Mean peak latencies (in milliseconds) of the two early waves (p13 and n23, recorded as P1 and N1, respectively) were measured on the side ipsilateral to the stimulation.
Recordings were determined by averaging 200 stimuli, and two traces from each test were assessed to estimate reproducibility . Skin resistance was lower than 5 kV. The initial negative–positive biphasic waveform comprised peaks N1 and P1. The amplitudes of N1 and P1 at the maximal intensity of stimulation were analyzed in each evaluation. Statistical analysis
Data were analyzed using IBM SPSS Statistics for Windows, version 21.0 (IBM Corp., Armonk, NY, USA). The results for the three evaluation time points (T0, T1, and T2) were compared statistically with repeated measures analysis of variance (ANOVA) and paired samples t-tests. The results for isolated maxillary advancement and concomitant maxillary impaction – advancement were also compared statistically using the Student t-test. Continuity (Yates) correction, Fisher’s exact test, the x2 test, and the McNemar test were used for the nominal data. All differences associated with a chance probability of 0.05 or less were considered statistically significant. Results
The mean age of all included patients was 23 years. The mean amount of maxillary advancement was 5 mm and the mean amount of impaction was 1.5 mm. No complications were observed during the surgical procedures and no persistent BPPV occurred in any of the study patients. BPPV was diagnosed in three out of the 23 patients. Regarding the Dix–Hallpike manoeuvre and positional tests, 11 patients had nystagmus at the T1 evaluation and seven at the T2 evaluation. The difference between the T0 and T1 time points was statistically significant (P = 0.001) (Table 1). When the patients who underwent isolated advancement were compared to those who underwent concomitant maxillary
Table 1. Distribution of nystagmus at each evaluation time point. Nystagmus, n (%) T0 0 (0%) T1 11 (47.8%) T2 7 (30.4%) P-valuea T0–T1 0.001** T0–T2 0.016* T1–T2 0.289 a
McNemar test. P < 0.05. ** P < 0.01. *
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
YIJOM-3534; No of Pages 5
BPPV following Le Fort I osteotomy Table 2. Distribution of nystagmus in the different groups (maxillary advancement with or without impaction) at each evaluation time point. With impaction
Without impaction
Nystagmus, n (%) T0 T1 T2
0 (0%) 8 (66.7%) 5 (41.7%)
0 (0%) 3 (27.3%) 2 (18.2%)
P-valuec T0–T1 T0–T2 T1–T2
0.008** 0.063 0.375
0.250 0.500 1.000
P-value – 0.141a 0.371b
a
Continuity (Yates) correction. Fisher’s exact test. McNemar test. ** P < 0.01. b c
Table 3. Distribution of the P1 and N1 values of the VEMP test at each evaluation time point. P1 right Mean SD
P1 left Mean SD
N1 right Mean SD
N1 left Mean SD
T0 T1 T2 P-valuea
15.42 2.32 16.31 3.52 15.38 2.64 0.193
16.09 2.22 15.13 3.18 15.74 2.38 0.457
24.15 2.66 24.73 4.05 23.97 3.27 0.237
23.83 2.78 22.9 3.05 23.34 3.03 0.540
P-valueb T0–T1 T0–T2 T1–T2
0.256 0.944 0.067
0.239 0.504 0.225
0.488 0.806 0.087
0.261 0.435 0.442
VEMP, vestibular evoked myogenic potential; SD, standard deviation. a Repeated measures analysis of variance. b Paired samples t-test.
advancement and impaction, no statistically significant difference was observed at any of the evaluation time points (Table 2). Regarding the P1 and N1 values of the VEMP tests for both the left and right ears of the patients, there were no statistically significant differences between the evaluation time points (Table 3). For concomitant advancement-impaction patients P1 and N1 values of the left ears are statistically significant at T1 point. The differences between T0–T1 and T1–T2 of right ears’ P1 values are also statistically significant
for these patients. For the isolated maxillary advancement patients; the differences between T0–T1 and T0–T2 of left ears’ P1 values, and the differences between T0–T1 and T1–T2 of left ears’ N1 values are statistically significant. (Tables 4 and 5). Discussion
The Le Fort I osteotomy is a routine procedure in the field of maxillofacial surgery and is usually associated with significant but rare postoperative complications, such as neurosensory deficit, pulpal sensitivity,
3
maxillary sinusitis, vascular complications, aseptic necrosis, unfavourable fractures, ophthalmic complications, and instability or non-union of the maxilla. BPPV has not been listed as a possible complication following conventional Le Fort I osteotomy.9 BPPV is the most common cause of vertigo of labyrinthine origin.4 Its pathology more frequently has a non-traumatic aetiology; however, head and cervical trauma can represent the cause of the underlying mechanism of BPPV. According to several clinical reports, it has been accepted that a sufficient surgical trauma from a mallet, osteotome, saw, or bur during maxillofacial procedures can lead to BPPV.10–12 In this study, BPPV was diagnosed in 13% of the patients, and the results at the first month postoperative evaluation showed a significant improvement when compared to the first week postoperative results. The Dix–Hallpike manoeuvre, positional test (supine roll rest), and more recent VEMP test are often used to confirm the diagnosis of BPPV. The Dix–Hallpike manoeuvre and the positional tests induce vertigo and a burst of nystagmus with characteristic features. Beshkar et al. evaluated the results of the Dix–Hallpike manoeuvre and positional tests in patients who had undergone Le Fort I osteotomy.8 The VEMP test is a clinical test that assesses the otolith function of the vestibular system and helps the clinician to perform a more effective examination for the diagnosis of BPPV. Changes in VEMP test results following Le Fort I osteotomy were evaluated in the present study. Significant changes of the P1 and N1 values of VEMP tests between the evaluation time points for isolated maxillary advancement and those for concomitant advancement-impaction patients might indicate the alteration of the vestibular function.
Table 4. P1 (initial positive biphasic waveform peak) values of the different groups at each evaluation time point. P1 right
With impaction Mean SD
Without impaction Mean SD
T0 T1 T2 P-valueb
14.86 3.09 17.36 2.99 16.06 2.79 0.011*
16.03 0.75 15.15 3.83 14.64 2.37 0.180
P-valuec T0–T1 T0–T2 T1–T2
0.011* 0.230 0.024*
0.456 0.070 0.561
P-valuea
P1 left
With impaction Mean SD
Without impaction Mean SD
0.227 0.136 0.206
T0 T1 T2 P-valueb
15.70 2.90 16.39 3.45 16.42 2.78 0.589
16.52 1.12 13.76 2.29 15.01 1.69 0.048*
P-valuec T0–T1 T0–T2 T1–T2
0.532 0.316 0.966
0.015* 0.035* 0.110
P-valuea 0.388 0.045* 0.160
SD, standard deviation. a Student t-test. b Repeated measures analysis of variance. c Paired samples t-test. * P < 0.05.
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
YIJOM-3534; No of Pages 5
4
Deniz et al.
Table 5. N1 (initial negative biphasic waveform peak) values of the different groups at each evaluation time point. N1 right
With impaction Mean SD
Without impaction Mean SD
T0 T1 T2 P-valueb
24.14 3.27 26.20 4.32 24.94 3.24 0.178
24.16 1.94 23.12 3.17 22.91 3.11 0.547
P-valuec T0–T1 T0–T2 T1–T2
0.105 0.434 0.076
P-valuea
N1 left
With impaction Mean SD
Without impaction Mean SD
0.992 0.067 0.142
T0 T1 T2 P-valueb
23.70 3.01 24.36 2.82 23.87 3.03 0.762
23.97 2.65 21.31 2.52 22.76 3.08 0.045*
P-valuec T0–T1 T0–T2 T1–T2
0.473 0.660 0.582
0.049* 0.339 0.033*
0.320 0.258 0.694
P-valuea 0.819 0.012* 0.392
SD, standard deviation. a Student t-test. b Repeated measures analysis of variance. c Paired samples t-test. * P < 0.05.
Kim et al. suggested that indirect trauma to the labyrinth of the internal ear due to the use of mallets and osteotomes on the maxilla during Le Fort I osteotomy may cause BPPV.13 Furthermore, down-fracturing of the maxilla after osteotomy can also displace otoliths into the semicircular canals. The close relationship of the temporal bone and maxilla explains the transfer of force between the two bones. Osteotomes must be placed extremely close to the temporal bone, especially during the pterygoid osteotomy of the Le Fort I procedure. Sufficient force is exerted through mechanical energy to displace otoliths and possibly lead to fracture of the cranial bones. Maxillofacial surgeons should be aware of the potential risk of BPPV following Le Fort I osteotomy and atraumatic force should be considered for such procedures. Patient complaints of varying degrees related to the surgical trauma and general anaesthesia have been observed following orthognathic surgery. Postsurgical complaints such as nausea, low blood pressure, dizziness, and weakness could obscure the clinical symptoms of BPPV. Maxillofacial surgeons have little knowledge about BPPV. The diagnosis of BPPV is made based on the patient’s history and it can easily be established using the specific clinical examination methods performed in the current study. Investigations for BPPV should be considered in patients who are experiencing prolonged positional dizziness symptoms following orthognathic surgery. Patients with BPPV do not experience severe vertigo during daytime activities performed in the upright position.14 Sitting up from a supine position may provoke BPPV, as can lying down in bed, turning over in bed from one side to the other, and straightening and looking up after bending over. BPPV disturbs the patient’s daily life, but it can be resolved
through the application of a simple manoeuvre by a specialist. BPPV may resolve spontaneously, or it can be treated using the Epley manoeuvre, barbeque roll, simple headshake, or the Gufoni manoeuvre (and its variations), which return the displaced otoliths to their original position in the ear canal.15 Three cases of BPPV were diagnosed in the current study. The BPPV resolved spontaneously in two of these cases, and the performance of an Epley manoeuvre was required to correct the condition of the third patient, leading to recovery. In this study, the pterygomaxillary dysjunction was performed using a reciprocating saw and curved osteotomes. BPPV was diagnosed in three of the 23 patients. Compared with the conventional pterygomaxillary dysjunction, the twist technique using straight osteotomes or piezoelectric surgery may reduce the risk of BPPV. BPPV is a possible early postoperative complication of Le Fort I osteotomy. It most probably results from the indirect forces of the osteotomes transferring through the neighbouring bones to the inner ear, where otoliths are dislodged and move within the semicircular canals, causing vertigo. Surgeons should be aware of this complication and a diagnosis of BPPV should be considered in patients who have undergone Le Fort I osteotomy. The interference between the maxillary segment and pterygoid plates could be removed more safely by paying sufficient attention and controlling the force during the osteotomy. Funding
There was no source of funding for this research. Competing interests
There are no competing interests to report.
Ethical approval
The study was approved by the Institutional Review Board and Ethics Committee of Baskent University (project number D-KA15103). Patient consent
Informed consent was obtained from each patient to participate in this study. References 1. Bayram B, Deniz K, Aydin E, Uckan S. Is auditory function affected after Le Fort I osteotomy. Int J Oral Maxillofac Surg 2012;41:709–12. 2. Yaghmaei M, Ghoujeghi A, Sadeghinejad A, Aberoumand D, Seifi M, Saffarshahroudi A. Auditory changes in patients undergoing orthognathic surgery. Int J Oral Maxillofac Surg 2009;38:1148–53. 3. Wong LL, Samman N, Whitehill TL. Are hearing and middle ear statuses at risk in Chinese patients undergoing orthognathic surgery. Clin Otolaryngol Allied Sci 2002; 27:480–4. 4. Chiarella G, Leopardi G, De Fazio L, Chiarella R, Cassandro E. Benign paroxysmal positional vertigo after dental surgery. Eur Arch Otorhinolaryngol 2008;265:119–22. 5. Gutie´rrez CR, Go´mez ER. Positional vertigo afterwards maxillary dental implant surgery with bone regeneration. Med Oral Patol Oral Cir Bucal 2007;12:E151–3. 6. Vernamonte S, Mauro V, Vernamonte S, Messina AM. An unusual complication of osteotome sinus floor elevation: benign paroxysmal positional vertigo. Int J Oral Maxillofac Surg 2011;40:216–8. 7. Pen˜arrocha-Diago M, Rambla-Ferrer J, Perez V, Pe´rez-Garrigues H. Benign paroxysmal vertigo secondary to placement of maxillary implants using the alveolar expansion technique with osteotomes: a study of 4 cases. Int J Oral Maxillofac Implants 2008;23:129–32. 8. Beshkar M, Hasheminasab M, Mohammadi F. Benign paroxysmal positional vertigo as a
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
YIJOM-3534; No of Pages 5
BPPV following Le Fort I osteotomy complication of orthognathic surgery. J Craniomaxillofac Surg 2013;41:59–61. 9. Garg S, Kaur S. Evaluation of post-operative complication rate of Le Fort I osteotomy: a retrospective and prospective study. J Maxillofac Oral Surg 2014;13:120–7. 10. Carlos R, Ronen Levite G, Joffe V, Gadoth N. Is posttraumatic benign paroxysmal positional vertigo different from the idiopathic form. Arch Neurol 2004;61:1590–3. 11. Sammartino G, Mariniello M, Scaravilli MS. Benign paroxysmal positional vertigo following closed sinus floor elevation procedure: mallet osteotomes vs. screwable osteotomes. A triple blind randomized
controlled trial. Clin Oral Implants Res 2011;22:669–72. 12. Park SK, Kim SY, Han KH, Hong SK, Kim JS, Koo JW. Benign paroxysmal positional vertigo after surgical drilling of the temporal bone. Otol Neurotol 2013;34: 1448–55. 13. Kim MS, Lee JK, Chang BS, Um HS. Benign paroxysmal positional vertigo as a complication of sinus floor elevation. J Periodontal Implant Sci 2010;40:86–9. 14. Koc EA, Koc B, Eryaman E, Ozluoglu LN. Benign paroxysmal positional vertigo following septorhinoplasty. J Craniofac Surg 2013;24:e89–90.
5
15. Zappia JJ. Benign paroxysmal positional vertigo. Curr Opin Otolaryngol Head Neck Surg 2013;21:480–6.
Address: Kagan Deniz Baskent Universitesi ˙Istanbul Hastanesi Poliklinikler 3 Mahir ˙Iz cad. No: 43 Altunizade Istanbul 34662 Turkey Tel: +90 216 6515153; Fax: +90 216 6513882 E-mail: [email protected]
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
Int. J. Oral Maxillofac. Surg. 2016; xxx: xxx–xxx http://dx.doi.org/10.1016/j.ijom.2016.10.007, available online at http://www.sciencedirect.com
Clinical Paper Orthognathic Surgery
Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy
¨ .Koc¸2, K. Deniz1, S. S. Akdeniz1, A. O S. Uc¸kan1, L. N. Ozluog˘lu2 1
Department of Oral and Maxillofacial Surgery, Baskent University School of Dentistry, Ankara, Turkey; 2Department of Otorhinolaryngology, Baskent University School of Medicine, Ankara, Turkey
¨ . Koc¸, S. Uc¸kan, L. N. Ozluog˘lu: Evaluation of benign K. Deniz, S. S. Akdeniz, A. O paroxysmal positional vertigo following Le Fort I osteotomy. Int. J. Oral Maxillofac. Surg. 2016; xxx: xxx–xxx. # 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Abstract. The Le Fort I osteotomy is widely used to correct dentofacial deformities. Benign paroxysmal positional vertigo (BPPV) is a common vestibular end organ disorder characterized by short, often recurrent episodes of vertigo. Head trauma is one of the known causes of BPPV. During pterygoid osteotomy, the surgical trauma induced by percussion with the surgical mallet and osteotomes can displace otoliths into the semicircular canal, resulting in BPPV. The aim of this study was to evaluate the potential risk of occurrence of BPPV in individuals undergoing Le Fort I osteotomy. Twenty-three patients were included in this study. The Dix–Hallpike manoeuvre, positional tests using electronystagmography, and vestibular evoked myogenic potential (VEMP) tests were performed 1 week before surgery (T0), 1 week after surgery (T1), and 1 month after surgery (T2). The results were compared statistically. BPPV was observed in three patients. Eleven patients had nystagmus at the T1 evaluation and seven at the T2 evaluation. The difference between the T0 and T1 time points was statistically significant (P = 0.001). BPPV is a possible complication of Le Fort I osteotomy. Surgeons should be aware of this complication, and the diagnosis of BPPV should be considered in patients who have undergone Le Fort I osteotomy.
Patients with dentofacial deformities, such as congenital and acquired abnormal positioning of the maxilla, mandible, or both, can experience problems with facial aesthetics, mastication, and speech. The correction of midfacial deformities often involves Le Fort I osteotomy with advancement, impaction, or a combination of these movements. The Le Fort I osteotomy involves surgical trauma induced by percussion with 0901-5027/000001+05
the surgical mallet and osteotomes, along with hyperextension of the neck. It has been shown that this surgical trauma can promote different types of ear problems, such as decreased hearing sensitivity, middle ear pressure, and auditory function, because of the close relationship between the ear and the sphenoid bone.1–3 Benign paroxysmal positional vertigo (BPPV) is a common vestibular end organ disorder characterized by short, often
Key words: benign paroxysmal positional vertigo; Le Fort I; orthognathic surgery; vertigo. Accepted for publication 18 October 2016
recurrent, episodes of vertigo that are triggered by certain head movements in the plane of the semicircular canals. BPPV occurs in 15–20% of head trauma cases and is rarely reported after maxillofacial surgery. There are two pathophysiological mechanisms in BPPV: cupulolithiasis and canalithiasis. In cupulolithiasis, otoconial debris in the semicircular canal becomes attached to the cupula and the
# 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
YIJOM-3534; No of Pages 5
2
Deniz et al.
patient is rendered sensitive to gravity. In canalithiasis, calcium crystals, called otoliths, dislodge from the utricle of the inner ear and move within the lumen of the semicircular canals. When these otoliths move within the canal, they cause endolymph motion during the angular acceleration of the head that stimulates the affected canal, thereby causing vertigo. There are a few case reports and case series published in the literature concerning BPPV after dental and maxillofacial surgical procedures, such as impacted third molar removal, osteotome techniques for sinus floor elevation, alveolar augmentation by ridge splitting, and septorhinoplasty.4–7 There is only one clinical study suggesting that BPPV should be considered in patients who have undergone Le Fort I osteotomy,8 and knowledge about this complication following orthognathic surgery is still limited. The aims of this prospective study were to comprehensively evaluate the potential risk of occurrence of BPPV in individuals undergoing Le Fort I osteotomy and to compare the results of maxillary advancement and/or impaction procedures. Patients and methods
This study was approved by the institutional review board and ethics committee of the university. Written informed consent was obtained from all subjects. This prospective study was conducted between December 2011 and December 2014 in the department of oral and maxillofacial surgery of a university hospital in Istanbul, Turkey. A total of 23 consecutive patients (12 female and 11 male), ranging in age from 18 to 32 years, were included. All of the patients included were ASA I status according to the American Society of Anesthesiology (ASA) health status classification. Nasotracheal intubations were performed by the same anaesthesiologist using the same agent. The study patients underwent conventional Le Fort I osteotomy, and the pterygomaxillary dysjunction was performed with a reciprocating saw and curved osteotomes by the same surgical team. Postsurgical medication was standard for all subjects. Exclusion criteria were listed as having had a previous ear operation or ear anomaly, a history of BPPV, neurological disorders, orthognathic surgery, maxillofacial deformity, and failure to attend postoperative evaluation appointments. Electronystagmography (ENG) with the Dix–Hallpike manoeuvre, positional tests, and vestibular evoked myogenic potential (VEMP) tests were performed 1 week
before surgery (T0), 1 week after surgery (T1), and 1 month after surgery (T2) in the department of otorhinolaryngology, division of neuro-otology of the study university. All test results were evaluated by the senior author of this paper from the neurootology department (L.N.O.), who was blinded to the patient identities. The surgical procedure used was Le Fort I osteotomy with advancement (n = 11) or a combination of advancement and impaction (n = 12), with or without mandibular surgeries. For the Dix–Hallpike manoeuvre, the patient was asked to sit down, with the head turned approximately 458 to the right or left. The patient was then instructed to lie down in the dorsal decubitus position with the examiner holding their head. The head was kept at an approximately 308 extension. The diagnostic criteria included vertigo and the occurrence of characteristic mixed torsional and vertical nystagmus with the upper pole of the eye beating towards the dependent ear and vertical nystagmus beating towards the forehead. For the positional test, the patient was asked to lie down in the dorsal decubitus position with the head flexed anteriorly by 308. The patient was then instructed to turn the head to one side and keep it in that position for up to 1 min. The diagnostic criteria included provoked vertigo and horizontal nystagmus. The VEMP test was performed with the patient in a sitting position with his or her chin turned over the contralateral shoulder, tensing the sternocleidomastoid muscle (SCM). Surface electromyographic activity was recorded with an evoked acoustic potential system (VEMP System, Eclipse preamplifier EPA 4V, Smart EP 15; Interacoustics a/s, Assens, Denmark). Active non-inverting recording electrodes were placed in the middle third part of the SCM. Reference electrodes were placed ipsilateral to the sternal manubrium region near the tendon of the SCM and a ground electrode was placed in the centre of the forehead. The VEMP responses were obtained by binaural acoustic stimulation and recorded from bilateral SCMs. Tone bursts at 500 Hz were delivered through an inserted earphone at a rate of 5.1/s for an average of 200 repetitions (500 Hz, 120 dB SPL hearing level intensity, stimulation rate 5.1/s). Electromyographic signals were amplified and band-pass filtered (range 10–1500 Hz). Electromyographic signals were recorded for 50 ms. Mean peak latencies (in milliseconds) of the two early waves (p13 and n23, recorded as P1 and N1, respectively) were measured on the side ipsilateral to the stimulation.
Recordings were determined by averaging 200 stimuli, and two traces from each test were assessed to estimate reproducibility . Skin resistance was lower than 5 kV. The initial negative–positive biphasic waveform comprised peaks N1 and P1. The amplitudes of N1 and P1 at the maximal intensity of stimulation were analyzed in each evaluation. Statistical analysis
Data were analyzed using IBM SPSS Statistics for Windows, version 21.0 (IBM Corp., Armonk, NY, USA). The results for the three evaluation time points (T0, T1, and T2) were compared statistically with repeated measures analysis of variance (ANOVA) and paired samples t-tests. The results for isolated maxillary advancement and concomitant maxillary impaction – advancement were also compared statistically using the Student t-test. Continuity (Yates) correction, Fisher’s exact test, the x2 test, and the McNemar test were used for the nominal data. All differences associated with a chance probability of 0.05 or less were considered statistically significant. Results
The mean age of all included patients was 23 years. The mean amount of maxillary advancement was 5 mm and the mean amount of impaction was 1.5 mm. No complications were observed during the surgical procedures and no persistent BPPV occurred in any of the study patients. BPPV was diagnosed in three out of the 23 patients. Regarding the Dix–Hallpike manoeuvre and positional tests, 11 patients had nystagmus at the T1 evaluation and seven at the T2 evaluation. The difference between the T0 and T1 time points was statistically significant (P = 0.001) (Table 1). When the patients who underwent isolated advancement were compared to those who underwent concomitant maxillary
Table 1. Distribution of nystagmus at each evaluation time point. Nystagmus, n (%) T0 0 (0%) T1 11 (47.8%) T2 7 (30.4%) P-valuea T0–T1 0.001** T0–T2 0.016* T1–T2 0.289 a
McNemar test. P < 0.05. ** P < 0.01. *
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
YIJOM-3534; No of Pages 5
BPPV following Le Fort I osteotomy Table 2. Distribution of nystagmus in the different groups (maxillary advancement with or without impaction) at each evaluation time point. With impaction
Without impaction
Nystagmus, n (%) T0 T1 T2
0 (0%) 8 (66.7%) 5 (41.7%)
0 (0%) 3 (27.3%) 2 (18.2%)
P-valuec T0–T1 T0–T2 T1–T2
0.008** 0.063 0.375
0.250 0.500 1.000
P-value – 0.141a 0.371b
a
Continuity (Yates) correction. Fisher’s exact test. McNemar test. ** P < 0.01. b c
Table 3. Distribution of the P1 and N1 values of the VEMP test at each evaluation time point. P1 right Mean SD
P1 left Mean SD
N1 right Mean SD
N1 left Mean SD
T0 T1 T2 P-valuea
15.42 2.32 16.31 3.52 15.38 2.64 0.193
16.09 2.22 15.13 3.18 15.74 2.38 0.457
24.15 2.66 24.73 4.05 23.97 3.27 0.237
23.83 2.78 22.9 3.05 23.34 3.03 0.540
P-valueb T0–T1 T0–T2 T1–T2
0.256 0.944 0.067
0.239 0.504 0.225
0.488 0.806 0.087
0.261 0.435 0.442
VEMP, vestibular evoked myogenic potential; SD, standard deviation. a Repeated measures analysis of variance. b Paired samples t-test.
advancement and impaction, no statistically significant difference was observed at any of the evaluation time points (Table 2). Regarding the P1 and N1 values of the VEMP tests for both the left and right ears of the patients, there were no statistically significant differences between the evaluation time points (Table 3). For concomitant advancement-impaction patients P1 and N1 values of the left ears are statistically significant at T1 point. The differences between T0–T1 and T1–T2 of right ears’ P1 values are also statistically significant
for these patients. For the isolated maxillary advancement patients; the differences between T0–T1 and T0–T2 of left ears’ P1 values, and the differences between T0–T1 and T1–T2 of left ears’ N1 values are statistically significant. (Tables 4 and 5). Discussion
The Le Fort I osteotomy is a routine procedure in the field of maxillofacial surgery and is usually associated with significant but rare postoperative complications, such as neurosensory deficit, pulpal sensitivity,
3
maxillary sinusitis, vascular complications, aseptic necrosis, unfavourable fractures, ophthalmic complications, and instability or non-union of the maxilla. BPPV has not been listed as a possible complication following conventional Le Fort I osteotomy.9 BPPV is the most common cause of vertigo of labyrinthine origin.4 Its pathology more frequently has a non-traumatic aetiology; however, head and cervical trauma can represent the cause of the underlying mechanism of BPPV. According to several clinical reports, it has been accepted that a sufficient surgical trauma from a mallet, osteotome, saw, or bur during maxillofacial procedures can lead to BPPV.10–12 In this study, BPPV was diagnosed in 13% of the patients, and the results at the first month postoperative evaluation showed a significant improvement when compared to the first week postoperative results. The Dix–Hallpike manoeuvre, positional test (supine roll rest), and more recent VEMP test are often used to confirm the diagnosis of BPPV. The Dix–Hallpike manoeuvre and the positional tests induce vertigo and a burst of nystagmus with characteristic features. Beshkar et al. evaluated the results of the Dix–Hallpike manoeuvre and positional tests in patients who had undergone Le Fort I osteotomy.8 The VEMP test is a clinical test that assesses the otolith function of the vestibular system and helps the clinician to perform a more effective examination for the diagnosis of BPPV. Changes in VEMP test results following Le Fort I osteotomy were evaluated in the present study. Significant changes of the P1 and N1 values of VEMP tests between the evaluation time points for isolated maxillary advancement and those for concomitant advancement-impaction patients might indicate the alteration of the vestibular function.
Table 4. P1 (initial positive biphasic waveform peak) values of the different groups at each evaluation time point. P1 right
With impaction Mean SD
Without impaction Mean SD
T0 T1 T2 P-valueb
14.86 3.09 17.36 2.99 16.06 2.79 0.011*
16.03 0.75 15.15 3.83 14.64 2.37 0.180
P-valuec T0–T1 T0–T2 T1–T2
0.011* 0.230 0.024*
0.456 0.070 0.561
P-valuea
P1 left
With impaction Mean SD
Without impaction Mean SD
0.227 0.136 0.206
T0 T1 T2 P-valueb
15.70 2.90 16.39 3.45 16.42 2.78 0.589
16.52 1.12 13.76 2.29 15.01 1.69 0.048*
P-valuec T0–T1 T0–T2 T1–T2
0.532 0.316 0.966
0.015* 0.035* 0.110
P-valuea 0.388 0.045* 0.160
SD, standard deviation. a Student t-test. b Repeated measures analysis of variance. c Paired samples t-test. * P < 0.05.
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
YIJOM-3534; No of Pages 5
4
Deniz et al.
Table 5. N1 (initial negative biphasic waveform peak) values of the different groups at each evaluation time point. N1 right
With impaction Mean SD
Without impaction Mean SD
T0 T1 T2 P-valueb
24.14 3.27 26.20 4.32 24.94 3.24 0.178
24.16 1.94 23.12 3.17 22.91 3.11 0.547
P-valuec T0–T1 T0–T2 T1–T2
0.105 0.434 0.076
P-valuea
N1 left
With impaction Mean SD
Without impaction Mean SD
0.992 0.067 0.142
T0 T1 T2 P-valueb
23.70 3.01 24.36 2.82 23.87 3.03 0.762
23.97 2.65 21.31 2.52 22.76 3.08 0.045*
P-valuec T0–T1 T0–T2 T1–T2
0.473 0.660 0.582
0.049* 0.339 0.033*
0.320 0.258 0.694
P-valuea 0.819 0.012* 0.392
SD, standard deviation. a Student t-test. b Repeated measures analysis of variance. c Paired samples t-test. * P < 0.05.
Kim et al. suggested that indirect trauma to the labyrinth of the internal ear due to the use of mallets and osteotomes on the maxilla during Le Fort I osteotomy may cause BPPV.13 Furthermore, down-fracturing of the maxilla after osteotomy can also displace otoliths into the semicircular canals. The close relationship of the temporal bone and maxilla explains the transfer of force between the two bones. Osteotomes must be placed extremely close to the temporal bone, especially during the pterygoid osteotomy of the Le Fort I procedure. Sufficient force is exerted through mechanical energy to displace otoliths and possibly lead to fracture of the cranial bones. Maxillofacial surgeons should be aware of the potential risk of BPPV following Le Fort I osteotomy and atraumatic force should be considered for such procedures. Patient complaints of varying degrees related to the surgical trauma and general anaesthesia have been observed following orthognathic surgery. Postsurgical complaints such as nausea, low blood pressure, dizziness, and weakness could obscure the clinical symptoms of BPPV. Maxillofacial surgeons have little knowledge about BPPV. The diagnosis of BPPV is made based on the patient’s history and it can easily be established using the specific clinical examination methods performed in the current study. Investigations for BPPV should be considered in patients who are experiencing prolonged positional dizziness symptoms following orthognathic surgery. Patients with BPPV do not experience severe vertigo during daytime activities performed in the upright position.14 Sitting up from a supine position may provoke BPPV, as can lying down in bed, turning over in bed from one side to the other, and straightening and looking up after bending over. BPPV disturbs the patient’s daily life, but it can be resolved
through the application of a simple manoeuvre by a specialist. BPPV may resolve spontaneously, or it can be treated using the Epley manoeuvre, barbeque roll, simple headshake, or the Gufoni manoeuvre (and its variations), which return the displaced otoliths to their original position in the ear canal.15 Three cases of BPPV were diagnosed in the current study. The BPPV resolved spontaneously in two of these cases, and the performance of an Epley manoeuvre was required to correct the condition of the third patient, leading to recovery. In this study, the pterygomaxillary dysjunction was performed using a reciprocating saw and curved osteotomes. BPPV was diagnosed in three of the 23 patients. Compared with the conventional pterygomaxillary dysjunction, the twist technique using straight osteotomes or piezoelectric surgery may reduce the risk of BPPV. BPPV is a possible early postoperative complication of Le Fort I osteotomy. It most probably results from the indirect forces of the osteotomes transferring through the neighbouring bones to the inner ear, where otoliths are dislodged and move within the semicircular canals, causing vertigo. Surgeons should be aware of this complication and a diagnosis of BPPV should be considered in patients who have undergone Le Fort I osteotomy. The interference between the maxillary segment and pterygoid plates could be removed more safely by paying sufficient attention and controlling the force during the osteotomy. Funding
There was no source of funding for this research. Competing interests
There are no competing interests to report.
Ethical approval
The study was approved by the Institutional Review Board and Ethics Committee of Baskent University (project number D-KA15103). Patient consent
Informed consent was obtained from each patient to participate in this study. References 1. Bayram B, Deniz K, Aydin E, Uckan S. Is auditory function affected after Le Fort I osteotomy. Int J Oral Maxillofac Surg 2012;41:709–12. 2. Yaghmaei M, Ghoujeghi A, Sadeghinejad A, Aberoumand D, Seifi M, Saffarshahroudi A. Auditory changes in patients undergoing orthognathic surgery. Int J Oral Maxillofac Surg 2009;38:1148–53. 3. Wong LL, Samman N, Whitehill TL. Are hearing and middle ear statuses at risk in Chinese patients undergoing orthognathic surgery. Clin Otolaryngol Allied Sci 2002; 27:480–4. 4. Chiarella G, Leopardi G, De Fazio L, Chiarella R, Cassandro E. Benign paroxysmal positional vertigo after dental surgery. Eur Arch Otorhinolaryngol 2008;265:119–22. 5. Gutie´rrez CR, Go´mez ER. Positional vertigo afterwards maxillary dental implant surgery with bone regeneration. Med Oral Patol Oral Cir Bucal 2007;12:E151–3. 6. Vernamonte S, Mauro V, Vernamonte S, Messina AM. An unusual complication of osteotome sinus floor elevation: benign paroxysmal positional vertigo. Int J Oral Maxillofac Surg 2011;40:216–8. 7. Pen˜arrocha-Diago M, Rambla-Ferrer J, Perez V, Pe´rez-Garrigues H. Benign paroxysmal vertigo secondary to placement of maxillary implants using the alveolar expansion technique with osteotomes: a study of 4 cases. Int J Oral Maxillofac Implants 2008;23:129–32. 8. Beshkar M, Hasheminasab M, Mohammadi F. Benign paroxysmal positional vertigo as a
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007
YIJOM-3534; No of Pages 5
BPPV following Le Fort I osteotomy complication of orthognathic surgery. J Craniomaxillofac Surg 2013;41:59–61. 9. Garg S, Kaur S. Evaluation of post-operative complication rate of Le Fort I osteotomy: a retrospective and prospective study. J Maxillofac Oral Surg 2014;13:120–7. 10. Carlos R, Ronen Levite G, Joffe V, Gadoth N. Is posttraumatic benign paroxysmal positional vertigo different from the idiopathic form. Arch Neurol 2004;61:1590–3. 11. Sammartino G, Mariniello M, Scaravilli MS. Benign paroxysmal positional vertigo following closed sinus floor elevation procedure: mallet osteotomes vs. screwable osteotomes. A triple blind randomized
controlled trial. Clin Oral Implants Res 2011;22:669–72. 12. Park SK, Kim SY, Han KH, Hong SK, Kim JS, Koo JW. Benign paroxysmal positional vertigo after surgical drilling of the temporal bone. Otol Neurotol 2013;34: 1448–55. 13. Kim MS, Lee JK, Chang BS, Um HS. Benign paroxysmal positional vertigo as a complication of sinus floor elevation. J Periodontal Implant Sci 2010;40:86–9. 14. Koc EA, Koc B, Eryaman E, Ozluoglu LN. Benign paroxysmal positional vertigo following septorhinoplasty. J Craniofac Surg 2013;24:e89–90.
5
15. Zappia JJ. Benign paroxysmal positional vertigo. Curr Opin Otolaryngol Head Neck Surg 2013;21:480–6.
Address: Kagan Deniz Baskent Universitesi ˙Istanbul Hastanesi Poliklinikler 3 Mahir ˙Iz cad. No: 43 Altunizade Istanbul 34662 Turkey Tel: +90 216 6515153; Fax: +90 216 6513882 E-mail: [email protected]
Please cite this article in press as: Deniz K, et al. Evaluation of benign paroxysmal positional vertigo following Le Fort I osteotomy, Int J Oral Maxillofac Surg (2016), http://dx.doi.org/10.1016/j.ijom.2016.10.007