Posterior Airway Space Research Articles

Comparison of Posterior Pharyngeal Airway Space at Sitting and Supine Positions in the PACU after Uvulopalatopharyngoplasty in Patients with Obstructive Sleep Apnea Syndrome

Background: Uvulopalatopharyngoplasty (UPPP) is one of the most common treatments for patients with obstructive sleep apnea syndrome (OSAS) who suffer from repetitive apnea and oxygen desaturation during sleep. It is important to properly manage the patient's airway in the PACU after surgery in order to prevent potential airway-related postoperative complications. Methods: 20 patient cases of ASA I or II who were over 20 years old and had undergone UPPP under general anesthesia were reviewed. In PACU, Posteri or pharyngeal airway space (PAS) was measured on a lateral cranial radiograph at both supine and sitting positions and the blood pressure and oxygen saturation were measured. Results: PAS significantly increased in the sitting position (avg. 11.7 mm in supine, 15.7 mm in sitting, P ＜ 0.05) but there was no influence on the blood pressure or oxygen saturation. Conclusions: PAS is associated with the patency of the airway and the increase of PAS in patients in the sitting position while in the PACU is helpful to airway management following UPPP. (Korean J Anesthesiol 2008; 54: 180∼4)

Avaliação cefalométrica do espaço aéreo posterior em pacientes com oclusão Classe II submetidos à cirurgia ortognática

OBJETIVO: o avanço maxilomandibular é um método cirúrgico comumente usado no tratamento de pacientes acometidos pela Síndrome da Apnéia Obstrutiva do Sono (SAOS) e portadores de anormalidades anatômicas identificáveis neste complexo, que estreitam e/ou obstruem o espaço aéreo. O intuito deste estudo foi analisar variações cefalométricas do espaço aéreo faríngeo em indivíduos Classe II de Angle, após a cirurgia ortognática. METODOLOGIA: a amostra consistiu de telerradiografias laterais equivalentes aos períodos pré e pós-operatório de 30 indivíduos, divididos no grupo com avanço cirúrgico mandibular (n=15) e no grupo com avanço maxilomandibular (n=15). Os parâmetros cefalométricos usados permitiram avaliar o espaço aéreo posterior em 3 níveis: a hipofaringe (PFI-V), a orofaringe (PFM-PM, PFM-PO, PFM-U, PFM-Up) e a nasofaringe (PFM-PN, pm-PFS). A análise esquelética foi na base do crânio (N-S-Ba) e na mandíbula (Ar-Go-Me). A média das diferenças entre os valores pré e pós-operatórios das mensurações lineares (mm) e angulares (graus) foi avaliada pelo teste t pareado. RESULTADOS E CONCLUSÕES: estatisticamente, não houve redução do espaço aéreo faríngeo pós-avanço cirúrgico. O que se observou foi que apenas PFM-PO e PFS-pM se mantiveram constantes e na maioria restante os valores aumentaram.

Discussion: Childhood Temporomandibular Joint Fracture Leading to Obstructive Sleep Apnea Syndrome

This is a very intriguing case presentation that clearly demonstrates the medical complications of maxillofacial trauma. Mandibular facture may be viewed as the principle factor in the etiology of this patient’s obstructive sleep apnea (OSA), including the comorbidity of daytime fatigue, hypertension, congestive heart failure, stroke, and early death. The acquired micrognathic mandible appears to impinge on the posterior airway space by the retro position of the tongue base. 1 Bettega G. Pepin J.L. Levy P. et al. Surgical treatment of a patient with obstructive sleep apnea syndrome associated with temporomandibular joint destruction by rheumatoid arthritis. Plast Reconstr Surg. 1998; 101: 1045 Crossref PubMed Scopus (14) Google Scholar Base of tongue obstruction is a well-recognized and clinically obvious cause of OSA. 2 Davies S.F. Iber C. Obstructive sleep apnea associated with adult-acquired micrognathia from rheumatoid arthritis. Am Rev Respir Dis. 1983; 127: 245 PubMed Google Scholar , 3 Pepin J.L. et al. Evaluation of the upper airway in sleep apnea syndrome. Sleep. 1992; 15: S50 PubMed Google Scholar From a teaching standpoint, many aspects are worthy of discussion, beginning with pediatric treatment of condylar fractures and extending through delayed orthognathic/prosthetic reconstruction, temporomandibular joint (TMJ) reconstruction, and management of OSA.

Snoring in cleft patients with velopharyngoplasty

Some patients with cleft lip/palate or isolated cleft palate seem to develop snoring as one possible symptom of an obstructive sleep apnoea syndrome after velopharyngoplasty (VPP). The aim of this paper was to determine whether there was a difference in the posterior airway space (PAS) between patients with a VPP who snored and those who did not. Four standard parameters were measured in lateral cephalograms of 20 patients with cleft lip/palate and isolated cleft palate, without diagnosis of further syndromes (e.g. Pierre Robin sequence), having undergone VPP, to examine the dimensions of the PAS. Data were set in correlation to the symptom of snoring, and compared with those of 40 patients without cleft undergoing orthodontic treatment and with 20 patients with cleft lip/palate or isolated cleft palate but not VPP. Metric parameters were significantly different after VPP in patients with clefting and snoring compared to the group of cleft patients without snoring. All patients with clefts exhibited at least in one dimension a constriction when compared to patients without clefting. In conclusion, cleft lip/palate and isolated cleft palate patients tend to have constrictions of the PAS. VPP may induce snoring and further narrowing. Recall and analysis for obstructive sleep apnoea syndrome should be mandatory.

Mentoplastia para avanço do músculo genioglosso em pacientes com síndrome da apnéia-hipopnéia do sono obstrutiva e retrognatismo mandibular

A Síndrome da Apnéia-Hipopnéia do Sono Obstrutiva (SAHSO) é um doença de fisiopatologia complexa, e sua etiologia é multifatorial e não entendida completamente. Cirurgia com avanço do músculo genioglosso é indicado em obstrução na região de hipofaringe. OBJETIVO: Avaliar a eficácia e complicações da técnica de mentoplastia para avanço do músculo genioglosso em pacientes com síndrome da apnéia-hipopnéia do sono obstrutiva (SAHSO). MÉTODOS: Polissonografia, exame físico e análise cefalométrica foram realizados em 10 pacientes não-obesos, que apresentavam SAHSO leve ou moderada, índice de apnéia-hipopnéia (IAH) entre 5 e 30, obstrução de hipofaringe e retrognatismo mandibular. RESULTADOS: IAH pré-operatório médio foi de 12,4±4,6 diminuindo a média pós-operatória para 4,4±5,7 (p < 0,001). Quando 50% de redução do IAH pré-operatório foram escolhidos como parâmetro, o índice de sucesso foi de 70%. A análise cefalométrica revelou um aumento do espaço aéreo posterior (EAP) em todos os pacientes, a média pré-operatória foi de 7,9±2,3mm para uma média pós-operatória de 10,8±2,5mm (p < 0,001). CONCLUSÃO: Mentoplastia para avanço do músculo genioglosso parece reduzir os sinais da SAHSO, podendo ser considerada uma opção com tratamento cirúrgico em pacientes com obstrução na hipofaringe. Os dados coletados indicam esse procedimento como opção em pacientes com SAHSO e retrognatismo mandibular.

Genioplasty for genioglossus muscle advancement in patients with obstructive sleep apnea-hypopnea syndrome and mandibular retrognathia

SummaryObstructive sleep apnea syndrome is a complex disease, which the etiology is multifactorial and incompletely understood. Surgery with genioglossus advancement is indicated in hypopharynx obstruction.Aimevaluate the efficacy and complications of genioplasty technique for genioglossus muscle advancement in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS).Methodspolysomnography, physical examination and cephalometric analysis were performed in 10 non-obese patients, who presented mild or moderate OSAHS, an apnea-hypopnea index (AHI) between 5 and 30, with hypopharynx obstruction and mandibular retrognathia.Resultsthe AHI preoperative mean of 12.4±4.6 decreased to a postoperative mean of 4.4±5.7 (p < 0,001). When 50% reduction of preoperative AHI was chosen as a parameter, its rate was 70% (7/10). Cephalometric analysis revealed an increase in the posterior airway space (PAS) in all patients, from a preoperative mean value of 7.9±2.3mm to a postoperative mean value of 10.8±2.5mm (p < 0,001).Conclusiongenioplasty for genioglossus advancement seemed to reduce OSAHS signs, thus, it can be considered as an option for the surgical treatment of patients with hypopharynx obstruction. Data collected supports this surgical procedure as an option in patients with OSAHS and mandibular retrognathia.

Genioglossus advancement and hyoid suspension plus uvulopalatopharyngoplasty for severe OSAHS

To evaluate the outcome of a comprehensive surgical approach on the treatment of severe obstructive sleep apnea hypopnea syndrome (OSAHS) and find out possible predictors to the effectiveness of this approach. Eighteen patients received genioglossus advancement with hyoid suspension (GAHM) and uvulopalatopharyngoplasty (UPPP). The multiple logistic regression was used to analyze predictors for the outcome of treatment. Apnea hypopnea index (AHI) showed a reduction in the preoperative vs postoperative polysomnography (63.83 +/- 16.34 vs 21.43 +/- 20.34). With success defined as a final postoperative AHI of less than 20 events per hour, the success rate was 67%. The main differences between responders and nonresponders include age, posterior airway space (PAS), time of oxyhemoglobin saturation below 90% (CT90), and body mass index (BMI). Age and BMI were key predictors for therapeutic effect. GAHM plus UPPP may benefit severe OSAHS patients with oropharyngeal and hypopharyngeal obstruction. The success was best predicted by low BMI and younger age. This paper provides reference for patient selection of UPPP plus GAHM, and considers that older or morbidly obese patients with OSAHS should be excluded from this operation.

Treatment of severe micrognathia accompanying obstructive sleep apnea hypopnea syndrome with rigid external distractor

To approach the treatment of severe micrognathia accompanying obstructive sleep apnea hypopnea syndrome (OSAHS) with rigid external distractor (RED) in children. Six cases patients (4 males, 2 females) aged between 1.5 and 14 years, were diagnosed as ankylosis of temporomandibular joint severe micrognathia, and OSAHS. Under the nasal intubation and general anesthesia, the surgical procedures were performed by submandibular approach and osteotomy was done in mandible body. Mini plate was fixed and connected to RED. The distraction procedure was carried out Patients' profile, posterior airway space, and the results of polysomnography were improved significantly. There were no complications. Four months after removing the RED, the new bone was well formed. RED technique has advantages of uncomplicated procedures, high quality of new bone formation, and accurate regulation in the treatment of micrognathia. It is especially suitable for the treatment of children with severe micrognathia whose mandibular body is too small to insert the internal distractor.

Evaluation of the Posterior Airway Space Following Biobloc Therapy: Geometric Morphometrics

The aim of this study was to evaluate changes in the posterior airway space in patients following Biobloc therapy, using geometric morphometrics. Pre- and post-treatment lateral cephalographs of 53 children (mean age, 12.9±1.5 years; mean treatment time, 21.3±6.2 months) were scanned and 27 landmarks encompassing the airway were digitized. Mean configurations were computed using Procrustes superimposition, followed by principal components analysis (PCA) and finite-element scaling analysis (FESA). Marked shape-changes were identified using PCA for the airway following treatment (p<0.01). Using pseudo-colored FESA, a relative 31% increase in nasopharyngeal airway area was found above and behind the soft palate. Additionally, a 23% increase in oropharyngeal airway area was located behind the base of the tongue with a 9% increase in hypopharyngeal area near the level of the hyoid bone. Functional airway improvements are associated with Biobloc treatment in actively growing patients.

Chirurgische Behandlungsmöglichkeiten der obstruktiven Schlafapnoe

Obstructive sleep apnea (OSA) is a common disorder in adults, however it also occurs in neonates with severe mandibular hypoplasia. The clinical significance of OSA results from hypoxemia and sleep fragmentation due to a collapse of the upper airway. Recently OSA has received much attention due to its potentially serious consequences on cardiac function. Besides daytime sleepiness and fatigue life expectancy is significantly shortened by a higher risk for apoplectic insults and heart failures. This paper reviews common surgical procedures with an emphasis on jaw advancement procedures. In six adults (mean age 46,9 ys; 2 female, 4 male; BMI averaged 28kg/m(2)) suffering from OSA with a history of a long-lasting unsuccessful continuous positive airway pressure (CPAP) therapy a bimaxillary advancement was performed. The respiratory disturbance was preoperatively evaluated by polysomnography; daytime sleepiness was recorded according to the 'Epworth Sleepiness Scale'. Controls were performed six months after therapy. All patients had a regular intermaxillary relation. Bimaxillary advancement was planned and performed according to the principles of cranio-maxillofacial corrective surgery. To widen the posterior airway space much attention was focused on the advancement of the mandible by 10mm. The apnea/hypopnea index decreased from preoperatively 37/h to 4/h after treatment. The minimal peripheral oxygen saturation increased from 78% to 89%, whereas the average oxygen saturation raised from 92 to 95%. The arousal index decreased from 24/h to 9/h. Periods of snoring were reduced from 29,5% to 6,9%. According to the 'Epworth Sleepiness Scale' the patients' estimation improved from a level of 11 to 4. Sleep had a recuperating effect. All surgical procedures were uneventful. Standard treatment of OSA is the CPAP-therapy. In some patients, however, CPAP-therapy cannot be applied, fails or is not well accepted. A great variety of surgical procedures for the treatment of OSA have been described. Bimaxillary advancement in adults and osteodistraction in neonates are safe and successful surgical techniques for an immediate improvement in OSA. Osteodistraction treatment can help to avoid tracheotomy in neonates.

L'exploration téléradiographique des voies aériennes supérieures dans l'évaluation du traitement chirurgical des syndromes d'apnées obstructives du sommeil

A lateral cephalometric radiograph is frequently performed for diagnostic and pretherapeutic purposes in patients with obstructive sleep apnea syndrome (OSAS). We studied the prognostic value of this exploration in terms of therapeutic outcome in surgically treated patients. Fifty-five patients underwent surgery from May 1994 through December 1998. Forty-seven had phase I surgery (UPPP, hyothyrohyoidopexy and genioglossal advancement), 18 phase II surgery (bimaxillar advancement) after failure of a phase I procedure and 8 primary phase II surgery. For the "phase I" group: mean body mass index (BMI) was 26.3+/-2.9 kg/m2 and mean age was 47+/-11 years. For the "phase II" group: mean BMI was 25.9+/-3 kg/m2 and mean age was 48+/-9 years. Polysomnography was performed in all patients preoperatively and six months after each surgical procedure. The preoperative apnea-hypopnea index (AHI) was 45.2+/-26.8/h of sleep for the phase I group and 53.8+/-26.9/h for the phase II group. All the patients had a lateral cephalometric radiograph, preoperatively, postoperatively, and at 6 months. The following parameters were measured on each radiograph: posterior airway space (PAS), mandibular plane-hyoid bone distance (MPH), minimal retrolingual space, minimal retrovelar space, surfaces of the rhinopharynx, the oropharynx, the hypopharynx and total upper airway surface. Therapeutic success was defined as a AHI<15/h and 50% decrease compared with the preoperative AHI, associated with normal sleep structure, respiratory microarousal score less than 15/h, normal oxymetry and absence of symptoms. After phase I surgery: the success rate was 21.2%. For the whole group, the total upper airway surface has significatively increased between preoperative and immediate postoperative time, as well the MPH, the PAS and the minimal retrolingual space. But at the late postoperative control, no significative difference compared with the preoperative data has been observed. The comparison between failures and successes has demonstrated that there was no difference in surface or distance benefit between the two groups. But it existed a preoperative difference as the failures have a greater rhinopharynx and a shorter retro velar oropharynx compared with the successes. This difference has been noticed in the immediate postoperative time but not in the late postoperative time. In the "failure" group, the immediate postoperative increase in the upper airway surface, the PAS and the minimal retrolingual space was totally lost in the late postoperative control. In the opposite, in the "success" group, the minimal retro velar space was the only parameter significatively increased at the postoperative time. After phase II surgery: the success rate was 76.9%. All measured parameters except rhinopharynx surface and MPH were increased at last follow-up; part of the increase in the hypopharynx and the minimal retrolingual space observed postoperatively was lost during later follow-up. Nevertheless, in the "failure" group patients, no significant increase could be demonstrated at the last postoperative control. Linear parameters (PAS, minimal retro lingual and retro velar spaces) were smaller in the "successful" group than in the "failure" group. It is difficult to ascertain the exact contribution of the lateral cephalometric radiograph to the assessment of surgical outcome. Apparently, and independently of the technique used, part of the gain in the upper airway surface observed immediately after surgery is progressively lost. We were unable to define any parameter on the lateral cephalometric radiograph predictive of success after phase I surgery. Discrimination between success and failure after phase I surgery might be related to the stability of the increase in the minimal retro velar space and the MPH. For phase II surgery, the initial shortness of the upper airway surface is a good prognostic factor for therapeutic success, defined as a stable increase in the oropharynx.

Distraction osteogenesis in a severe mandibular deficiency

ObjectiveDistraction osteogenesis is an alternative treatment method for the correction of mandibular hypoplasia. In this case report, distraction with a multidirectional extraoral device was performed to gradually lengthen the corpus and ramus of a patient who had a severe hypoplastic mandible.Materials and methodsThe patient underwent bilateral extraoral ramus and corpus distraction osteogenesis. After seven days of latency period, distraction was performed 0.5 mm twice a day. Subsequent consolidation period was 12 weeks.ResultsThe patient's mandible was elongated successfully. Cephalometric analysis revealed that ANB angle decreased from 13° to 6°, overjet of 15 mm decreased to 4 mm, corpus length increased from 49 mm to 67 mm, and ramus length increased from 41 mm to 43 mm. Posterior airway space (PAS) also increased due to advancement of the mandible. In stereolithographic model evaluation it was determined that the distances from condylion to gonion and from gonion to pogonion increased.ConclusionSatisfactory results from both aesthetic and functional standpoints were obtained by distraction osteogenesis of the ramus and corpus.

Dynamic MRI Evaluation of Tongue Posture and Deglutitive Movements in a Surgically Corrected Open Bite

Tongue thrust usually develops in the presence of anterior open bite in order to achieve anterior valve function. In the literature, tongue thrust is described both as the result and the cause of open bite. If it is an adaptation to malocclusion, then tongue posture and deglutitive tongue movements should change after treatment. In this case report, an adult who had skeletal open bite and Class II malocclusion caused by mandibular retrusion was treated surgically. The mandible was advanced in a forward and upward direction with a sagittal split osteotomy. The open bite and Class II malocclusion were corrected and an increase in the posterior airway space (PAS) was observed. Pretreatment and posttreatment dynamic magnetic resonance imaging (MRI) revealed that tongue tip was retruded behind the incisors and contact of the tongue with the palate increased. It was also determined that the anterior and middle portions descended, whereas the posterior portion was elevated at all stages. Advancement of the mandible, correction of open bite, and an increase in PAS affected not only the tongue posture and deglutitive movements, but also the breathing pattern of the patient.

Management of a case of severe obstructive sleep apnea with acrylic herbst splint appliance: A case report

A middle aged serving soldier with severe obstructive sleep apnea and non compliance to CPAP was managed with acrylic Herbst splint oral appliance. The oral appliance enabled the patient to protrude the mandible and tongue forward, thus increasing the posterior airway space when in supine position. There was gross improvement on Apnea index and Epworth sleepiness scale.

Mandibular Advancement by Distraction Osteogenesis for Tracheostomy-Dependent Children With Severe Micrognathia

The purpose of this study was to evaluate mandibular lengthening by distraction osteogenesis (DO) to achieve decannulation of micrognathic children with "permanent" tracheostomies. Using a retrospective chart review, patients were included who had 1 ) airway compromise/tracheostomy, 2 ) micrognathia, 3 ) polysomnography-documented obstructive apnea, and 4 ) mandibular advancement using DO. Excluded were 1 ) adults, 2 ) neonates without tracheostomy, and 3 ) patients with central apnea. Patient age, past medical history, age at tracheostomy, and distraction protocol were documented. Oxygen saturation, posterior airway space (in millimeters), and sella-nasion-B point (SNB) angle were recorded. The distraction protocol consisted of a latency of 48 hours and a rate of 1 mm/day. There were 5 children, aged 2 to 14 years, who received a tracheostomy between ages 2 and 36 months for airway obstruction. All patients underwent bilateral mandibular distraction using semiburied, unidirectional devices. The average latency was 58 hours, the rate was 1 mm/day, the duration of fixation was 40 to 60 days, and the magnitude of advancement was 23 mm. Healing was evaluated by clinical, radiologic, and ultrasound examinations. No complications were experienced. Mean follow-up was 3.2 years. Postdistraction sleep studies demonstrated no obstructive apneic events and a mean oxygen saturation of 98% (preoperative, 76%, P < .005). Cephalometric values improved: posterior airway space 4 to 14 mm; SNB 66 degrees to 72 degrees ( P < .005 for both variables). Four of the 5 patients have been successfully decannulated to date. The results of this preliminary study indicate that mandibular advancement by DO is a potentially viable treatment option for tracheostomy-dependent children with upper airway obstruction secondary to micrognathia.

Clinical predictors in obstructive sleep apnoea patients with calibrated cephalometric analysis – a new approach1

Utilization of a new method to accurately quantify differences in cephalometric parameters between obstructive sleep apnoea (OSA) and normal patients, and to identify good predictors for OSA. To illustrate the ethnic differences in cephalometry. This prospective study involves 106 South-east Asians. A calibrated catheter is inserted into the upper airway during standard cephalometry to obtain the precise magnification and allow exact measurement of anatomical parameters of cephalometry in both erect and supine positions. The OSA patients have longer lower-facial length, narrower skull base, shorter and receding mandible, smaller posterior airway space (PAS), narrower retropalatal space, longer and thicker soft palate, smaller hard and soft palate angles longer tongue length and more inferiorly displaced hyoid. For the palatal level, retropalatal distance of 11.2 mm cut-off/predictive value for male (receiver operating characteristics (ROC) = 0.8414 with PPV = 77.46, NPV = 90.00) and 5.5 mm for female (ROC = 0.9180 with PPV = 100.00, NPV = 84.21) at erect position were selected. For retrolingual level, erect PAS of 10.1 mm cut-off/predictive value for male (ROC = 0.7000 with PPV = 78.38, NPV = 37.78), 5.3 mm for female (ROC = 0.7227 with PPV = 75.00, NPV = 75.00) were selected. Our study showed that South-east Asians have different cephalometric values compared with White people, Black people and Hispanics. This new method of cephalometry using a calibrated catheter provides an accurate and simple method of obtaining precise cephalometric measurements. There is no cephalometric data on OSA from South-east Asia available. These results suggested that surgeons managing OSA patients and using cephalometry as a diagnostic method should have a set of normative and OSA cephalometric values that apply to their local populations.

Morphological Changes of the Posterior Airway Space After Tongue Base Suspension

The objectives were 1) to demonstrate the efficacy of tongue base suspension with the Repose System in modifying the posterior airway space on the basis of morphological changes in the retrolingual space and 2) to determine the implications of this procedure for the treatment of obstructive sleep apnea syndrome on polysomnographic and psychometric data. A prospective, nonrandomized study. Polysomnography was performed before as well as 3 and 12 months after surgery in patients undergoing tongue base suspension using the Repose System. To identify morphological changes in the posterior airway space, lateral cephalometric radiography and videoendoscopy of the pharynx were performed preoperatively and postoperatively. Twenty-eight male patients with obstructive sleep apnea syndrome were included in the study. A suspension suture anchored intraorally at the mandible was passed submucosally in the body of the tongue, with suture tightness adjusted individually. The posterior airway space was widened by at least 2 mm in 60% of cases. Daytime sleepiness improved subjectively in 67% of patients, and the respiratory disturbance index improved postoperatively in 55%. The correlation between posterior airway space widening and the improvements in daytime sleepiness and respiratory disturbance index was not significant. Surgical intervention in obstructive sleep apnea syndrome with the Repose System does not result in permanent anatomical change in the posterior airway space.

Changes in tongue and hyoid positions, and posterior airway space following mandibular setback surgery

The postural response of the tongue after mandibular setback is clinically important for maintaining normal respiration. Although the hyoid bone moves progressively to adapt physiologically to the altered orofacial configuration following such surgery, it is not clear whether repositioning of the hyoid has an effect on the pharyngeal airway. In the present study, postoperative changes in hyoid position and pharyngeal airway space were assessed retrospectively in patients who had undergone mandibular setback surgery. Digitized lateral cephalograms from 30 mandibular setback surgery cases taken preoperatively, and 1 month and more than 1 year postoperatively, were used to examine pharyngeal airway morphology and the position of hyoid bone. A significant downward movement of the hyoid bone was found 1 month after surgery, while the pharyngeal airway dimensions at the tongue were maintained. More than 1 year after surgery, the hyoid position returned to its original position, resulting in a significant decrease in retrolingual airway dimension. The results indicate that mandibular setback causes airway narrowing late after surgery, while the early postoperative airway dimension is maintained. Long-term observations should be performed because of the changes of oropharyngeal configuration following mandibular setback.

Cephalometric assessment of the posterior airway space using a new tongue positioning system in osas patients

Purpose: Lateral cephalometric radiographs and the following cephalometric analysis are very important in diagnosis of the posterior airway space (PAS) in OSAS patients. Nevertheless, the position of the tongue and tilt of the head is not defined so that the measurement of the airway space is not correct. For this reason a special fixation system should be built so that the tongue could be localized and positioned during x-ray. Material and methods: The new positioning system of the tongue contents a hole like a bell for taking in the tongue. This hole is connected with a wreath bar and fixation elements. The teeth of the mandible and maxilla bite in the wreath. It is possible to move the mandible in each requested position and to measure the position at a scale on the bar. The bar is fixed at the xray apparatus so that the head is fixed in the vertical direction. Patients with OSAS are examined by lateral cephalometric radiographs using the new system. Then, the cephalometric analysis is carried out. Results: The exact localization and positioning of the tongue in lateral cephalometric radiographs could be guaranteed by using this special positioning bar, bell and fixation components. The scale of the bar offers the opportunity to make the x-ray in a defined situation like protrusion of the mandible. Therefore, a simulation of the effect of protrusion apparatus for therapy of OSAS can be simulated. For taking the x-ray with this system it is necessary to open the mouth. This leads to reduction in the PAS: the distance in the mandibula plane was reduced of 31 %, in the uvula tip plane of 22 % and the hyoid menton distance of 5 %. Conclusions: The new fixation and positioning system makes possible a reproducible localization and positioning of the tongue, so that the PAS can exact be measured. This method seems to become a new standard method in diagnosis of OSAS by lateral cephalometric radiographs. The normal values using this method for measurement the PAS have to be new defined.

Acurácia da análise cefalométrica da faringe para o diagnóstico da síndrome da apnéia obstrutiva do sono (SAOS)

&lt;span class="texto"&gt;Esta pesquisa teve por objetivo verificar a acurácia da cefalometria radiográfica das vias aéreas posteriores para o diagnóstico da SAOS. A amostra constou de 60 pacientes, todos com suspeita clínica de SAOS. Diagnóstico polissonográfico positivo: índice de apnéia-hipopnéia [I(A+H)] por hora de sono igual ou maior que 5 eventos. Diagnóstico cefalométrico positivo: EAPs (espaço aéreo posterior superior) &lt; 26mm e (ou) EAPm (espaço aéreo posterior médio) &lt; 9mm e/ou EAPi (espaço aéreo posterior inferior) &lt; 11mm. O estudo estatístico verificou a acurácia da análise cefalométrica, comparada ao exame polissonográfico (padrãoouro). A comparação foi estabelecida através dos testes de McNemar e kappa de Cohen. A sensibilidade da análise cefalométrica foi de 91.5%. A especificidade foi de 38.5%. O valor preditivo positivo foi de 84.3%. O valor preditivo negativo foi de 55.6%. Falso negativo = 4 (quatro) situações. Falso positivo = 8 (oito) situações. O teste de McNemar mostrou não haver diferença estatisticamente significante entre os resultados auferidos pela cefalometria e pela polissonografia (p = 0.388), e o nível de concordância calculado por meio do coeficiente kappa de Cohen foi de 33.7% (p = 0.007), significante para valores de p &lt; 0.05. A alta sensibilidade e o elevado valor preditivo positivo fazem da cefalometria radiográfica instrumento confiável, capaz de diagnosticar com alta acurácia pacientes portadores de SAOS, identificando o sítio obstrutivo relacionado à manifestação da condição. Entretanto, a baixa especificidade da cefalometria radiográfica e o seu valor preditivo negativo não permitem admiti-la como exame único.&lt;/span&gt;