Surgical treatment of obstructive sleep apnea by maxillomandibular advancement.

In recent years obstructive sleep apnea syndrome has gained increasing interest. Treatment of choice is nasal continuous positive airway pressure ventilation during sleep for upper airway patency, which does not cure sleep apnea and has to be applied throughout a patient's lifetime. In respect to various underlying pathomechanisms, in certain cases with craniofacial disorders, causal therapy by craniofacial osteotomies seems possible. A series of 21 consecutive patients with maxillary and mandibular deficiency were treated primarily with a 10-mm maxillomandibular advancement by retromolar sagittal split osteotomy and Le Fort-I osteotomy, respectively. Obstructive sleep apnea syndrome was considerably improved in all patients. In 20 of 21 patients, the postoperative respiratory disturbance index (RDI) was reduced clearly to under 10, oxygen saturation rose and sleep quality improved. This was achieved by a maxillomandibular advancement of 10 mm without secondary refinements. In one patient the RDI could only be reduced to 20, probably due to insufficient maxillary advancement; oxygen desaturations still existed despite secondary corrections. These results indicate that successful surgical treatment is possible in a high percentage of selected patients with certain craniofacial characteristics. In addition to cardiorespiratory polysomnography there should be routine cephalometric evaluation of all patients. Maxillomandibular advancement should be offered as an alternative therapy to all patients with maxillary and/or mandibular deficiency or dolichofacial type in combination with narrow posterior airway space.

Therapeutic electrical stimulation of the hypoglossal nerve in obstructive sleep apnea.

BACKGROUND: Hypoglossal nerve stimulation has been demonstrated to relieve upper airway obstruction acutely, but its effect on obstructive sleep apnea is not known. OBJECTIVE: To determine the response in obstructive sleep apnea to electrical stimulation of the hypoglossal nerve. METHODS: Eight patients with obstructive sleep apnea were implanted with a device that stimulated the hypoglossal nerve unilaterally during inspiration. Sleep and breathing patterns were examined at baseline before implantation and after implantation at 1, 3, and 6 months and last follow-up. RESULTS: Unilateral hypoglossal nerve stimulation decreased the severity of obstructive sleep apnea throughout the entire study period. Specifically, stimulation significantly reduced the mean apnea-hypopnea indices in non-rapid eye movement (mean +/- SD episodes per hour, 52.0 +/- 20.4 for baseline nights and 22.6 +/- 12.1 for stimulation nights; P<.001) and rapid eye movement (48.2 +/- 30.5 and 16.6 +/- 17.1, respectively; P<.001) sleep and reduced the severity of oxyhemoglobin desaturations. With improvement in sleep apnea, a trend toward deeper stages of non-rapid eye movement sleep was observed. Moreover, all patients tolerated long-term stimulation at night and did not experience any adverse effects from stimulation. Even after completing the study protocol, the 3 patients who remained free from stimulator malfunction continued to use this device as primary treatment. CONCLUSION: The findings demonstrate the feasibility and therapeutic potential for hypoglossal nerve stimulation in obstructive sleep apnea.

Morphology of the viscerocranium in obstructive sleep apnoea syndrome--cephalometric evaluation of 400 patients.

The aim of this study was the cephalometric evaluation of patients with obstructive sleep apnoea in order to see whether certain craniofacial characteristics exist. Additional to known skeletal facial parameters cephalometric analysis has been used to establish pharyngeal dimensions. Surprisingly, many patients with obstructive sleep apnoea (nearly 40%) showed certain craniofacial characteristics which apparently predispose to pharyngeal obstruction and to obstructive sleep apnoea. More than one third of 400 patients prove to have pharyngeal narrowing combined with more or less distinct maxillary and mandibular deficiency. Cephalometric evaluation helps to identify sleep apnoea patients, in whom maxillomandibular advancement surgery might be effective in the treatment of obstructive sleep apnoea. According to our results, an indication for surgical treatment by maxillomandibular advancement exists in patients with maxillary and especially mandibular deficiency combined with pharyngeal narrowing.

Acoustic rhinometry: rationale and perspectives.

Acoustic rhinopharyngometry provides a new, non-invasive access to upper airways geometry. In this experimental and clinical study the diagnostic value of acoustic rhinopharyngometry was investigated. In vitro measurements showed adequate accuracy, reliability and spatial resolution within the range of nasal and epipharyngeal dimensions. Clinical measurements confirmed reasonable reproducibility for the evaluation of nasal (NV) and epipharyngeal (EV) volume. Decongestion with xylometazoline resulted in a 36% enlargement of nasal volume on average. The alteration of pharyngeal soft tissues due to maxillomandibulary advancement of 10 mm correlated to an increase of the EV-index of 6 cm3. Acoustic rhinometry identifies location and amount of nasal obstruction and in addition allows differentiation between obstruction due to mucosal hypertrophy and that due to skeletochondral deformity. Changes in the epipharyngeal volume following maxillary and mandibular osteotomies can be estimated in comparison with the preoperative situation.

Presurgical orthopaedic treatment using hard plates.

Our concept in the treatment of unilateral clefts of lip, alveolus and palate includes early maxillary orthopaedic treatment starting immediately after birth until the end of the first year of life and the surgical closure of the lip at three months and of the soft palate at twelve months. Hard palate and alveolus are closed after three years by secondary osteoplasty in the alveolar region. The appliance is made of hard acrylic resin and is adjusted monthly to allow for growth. It thus encourages passive orthopaedic guidance of maxillary growth. The local compatibility of the plate was excellent and the acceptance by the children created no problems until tooth eruption. Follow-up studies were conducted on twenty children treated in this way until three years of age. After the first year results show a good and harmonious arch alignment without any collapse of the alveolar segments. The cleft narrows and the steepness of the palatal slope flattens. This maxillary development is arrested after suspension of orthopaedic treatment, and a slight collapse of the alveolar segments is observed.

Surgical maxillofacial treatment of obstructive sleep apnea.

Obstructive sleep apnea is the most common sleep-related breathing disorder, with a surprisingly high prevalence. The treatment of choice is nasal continuous positive airway pressure (CPAP) ventilation during sleep, which has to be applied throughout the patient's whole life. Because of various underlying pathomechanisms in patients with certain craniofacial disorders--narrow posterior airway space and maxillary-mandibular deficiency--surgical therapy by craniofacial osteotomies seems possible. A series of 38 consecutive patients were treated by 10-mm maxillomandibular advancement by retromolar sagittal split osteotomy and Le Fort I osteotomy, respectively. Obstructive sleep apnea syndrome was improved considerably in all patients; there was no significant difference compared to the results under nasal CPAP. In 37 of 38 patients, the postoperative apnea-hypopnea index was reduced clearly to under 10 per hour, oxygen saturation rose, and sleep quality improved. This was achieved by maxillomandibular advancement of 10 mm without secondary refinements in all but 2 patients. In one patient, the apnea-hypopnea index could only be reduced to 20 per hour, probably because of insufficient maxillary advancement. These results indicate that successful surgical treatment is possible in a high percentage of selected patients with certain craniofacial characteristics. In addition to cardiorespiratory polysomnography, there should be routine cephalometric evaluation of all patients. Maxillomandibular advancement should be offered as an alternative therapy to all patients with maxillary and/or mandibular deficiency or dolichofacial type in combination with narrow posterior airway space.

Acoustic rhinometry: a new diagnostic procedure--experimental and clinical experience.

The diagnostic value of transnasal acoustic reflection measurements (Rhinoklack) was investigated in an experimental and clinical study. Within the range of nasal and epipharyngeal dimensions, in vitro and in vivo measurements showed satisfactory reproducibility. A simple maneuver helps to identify the transition from the rigid nasal cavity to the movable epipharynx. The location and the amount of nasal obstruction can be verified and traced back to their morphologic correlative. The effect of decongestion on nasal volume was measured for normal mucosa (41% enlargement) and mucosa altered by scar formation after septoplasty and turbinoplasty (21% enlargement). After maxillomandibulary advancement of 10 mm for obstructive sleep apnea, the EV index representing epipharyngeal volume (EV) showed an average increase of 6 cm3.

Mandibular setback for surgical correction of mandibular hyperplasia--does it provoke sleep-related breathing disorders?

The question has arisen as to whether mandibular setback may possibly cause sleep-related breathing disorders (SRBD). To evaluate the possible effects of mandibular setback on posterior airway space (PAS), 16 consecutive patients were examined prospectively. All patients underwent surgical mandibular setback using bilateral sagittal split osteotomy. Polysomnographic evaluation for SRBD was performed according to the Marburg graded diagnostic protocol before and after surgery. Cephalometric analysis was performed preoperatively, and 1 week, 3 months, and 1 year postoperatively, with particular attention to pharyngeal changes. PAS decreased considerably in all patients. Nevertheless, the preoperative PAS was enlarged in all patients with mandibular hyperplasia compared to normal subjects. Despite the pharyngeal narrowing, there was no evidence of postoperative SRBD in any of these patients. SRBD as a consequence of mandibular setback may be rare; nevertheless, the pharyngeal airway does decrease.

Resorbable dowels for osteosynthesis of noncongruent bone fragments.

Dowels, in contrast to screws, offer the great advantage in osteosynthesis that no pressure peaks occur by functional loading rectangular to the screw axis; consequently, there is no bone resorption and no loosening of the fixation because of the even contact of dowel and bony surface. However, dowels must be made of resorbable materials because they cannot be removed. We developed double-spreading dowels with a slotted tube whose outside is cylindric and the inside conical at both ends. Two conical screws in the core of the dowel moved toward each other cause symmetric expansion of the outer surface. Dowel material consisted of polylactic acid with an inherent viscosity > 7 dl/g (Resomer 214, Böhringer Ingelheim). A model simulating retromolar sagittal split osteotomy was chosen for experimental research because, in this case, noncongruent bone segments have to be osteosynthesized to regenerate in the sense of distance osteogenesis. Two segments of synthetic material were synthesized like proximal and distal segments after retromolar sagittal split osteotomy fixed by two or three dowels without coherent contact. The synthesized segments underwent a continuous jiggling stress test comparable with the physiologic stress of a jaw for about 4 weeks. Dowel fixation proved to be nearly as stable as position-screw fixation. Resorbable dowel fixation yields experimentally the required stability for the time needed for bony regeneration.

Four-year-old girl with Goldenhar-sequence and severe obstructive sleep apnea, symptoms, diagnosis and therapy.

Recently sleep related breathing disorders in children have received considerable attention. Unfortunately, cardiorespiratory polygraphy is expensive and time-consuming, and up until now today only a few pediatric hospitals have complete facilities for all-night cardiorespiratory polygraphy. Nevertheless, the prevalence of sleep related breathing disorders in children is higher than has previously been thought. To show the importance of proper diagnosis of sleep related breathing disorders, we report a case of a 4-year-old girl with severe obstructive sleep apnea caused by Goldenhar-sequence (facio-auriculo-vertebral dysplasia). Despite some treatment efforts to correct the aplastic right mandible, the symptoms of obstructive sleep apnea were not immediately recognized and remained untreated. Untreated obstructive sleep apnea led to growth and mental retardation. After polygraphic confirmation of obstructive sleep apnea and appropriate interdisciplinary treatment, the 4-year-old girl made rapid advances in growth and mental development.

The one-stage repair of bilateral cleft lip.

Twenty children with broad, complete clefts of lip, alveolus, and palate were studied. For functional restoration of the lip in complete bilateral clefts we advocate a one-stage modification of the Millard procedure even if the clefts are broad. Orthodontic treatment is done first to achieve maximal maxillary growth. Reconstruction of the lip is done at the age of 5 to 6 months. Our method of lip restoration is described with special attention to the muscle reconstruction. The lengthening of the columella, which is done at the age of 4 years, is still a problem.

[Obstructive sleep apnea in the child: an interdisciplinary treatment concept with special reference to craniofacial changes]. / Obstruktive schlafbezogene Atmungsstörungen beim Kind: Ein interdisziplinäres Behandlungskonzept unter besonderer Berücksichtigung kraniofazialer Veränderungen.

Diagnosis and therapy of obstructive sleep-related breathing disturbances SRBD in adults may not be applied without hesitation to children. SRBD in newborn and infants are often due to craniofacial disturbances (Pierre Robin syndrome, Goldenhars syndrome etc.), obesity is of minor importance. More than 30 infants with SRBD and craniofacial changes have been diagnosed and successfully treated over a 2-year period. Conservative therapy starts immediately after birth. The first step in newborn with Pierre Robin syndrome, for instance, is prone position for protrusion of tongue and mandible and mandibular growth stimulation. Intermediate nightly nasopharyngeal tubes are an alternative to nCPAP-/BiPAP treatment. Conventional orthopaedic/orthodontic treatment should not be neglected, even if it takes years to become effective. Surgical therapies are able to support, sometimes to replace or at least to shorten conservative methods. In rare cases when prone position in combination with palatal plates in cases of Robin syndrome, for instance, are not fully effective, mandibular extension is indicated. Aplasia or defects demand adequate surgical reconstruction, even if this does not necessarily mean abolishment of SRBD. In contrast to adults adenotonsillectomy is highly effective in infants and does not only reduce SRBD, but also improves nasal breathing and thus positively influences facial growth. A relatively new method is gradual mandibular distraction osteogenesis according to Ilizarov, which also enhances soft tissue growth. Maxillary and mandibular advancement osteotomies should not be considered before the termination of facial growth. Thanks to this refined treatment concept we were able to avoid tracheotomies in children during the past few years.

The influence of maxillary osteotomy on nasal airway patency and geometry.

Maxillary surgical repositioning affects nasal airway size. This study recorded nasal airway changes by acoustic rhinometry in patients with maxillary surgical repositioning after Le Fort I osteotomies. These changes were compared to the amount of skeletal movement by means of preoperative and 6-week postoperative lateral cephalography. Vertical linear movement of the posterior maxilla showed a very close relationship to volume changes in the posterior nasal segment. Anterior nasal volume changes can not be considered as a pure function of the direction and amount of skeletal movement. The greatest amount of cranial displacement tolerated without impaired nasal patency in this study was 7 mm.

[Surgical treatment of obstructive sleep apnea syndrome by osteotomy of the facial skeleton]. / Die chirurgische Behandlung des obstruktiven Schlafapnoesyndroms durch Gesichtsskelettosteotomien.

At the Philipps-University Marburg 14 patients with obstructive sleep apnoea syndrome (OSAS) have so far been successfully treated by surgical maxillo-mandibular advancement. These results clearly indicate that surgical treatment and cure of OSAS by maxillo-mandibular osteotomy is possible in case of an appropriate indication.

[Functional anatomy of the upper airway: cephalometric and reflective acoustic studies]. / Die funktionelle Anatomie der oberen Atemwege: zephalometrische und reflexions-akustische Untersuchungen.

Cephalometric analysis is an effective tool for the evaluation of craniofacial and pharyngeal changes in obstructive sleep apnoea. Meanwhile even for pharyngeal changes a lot of average values exist, which show significant differences for many cephalometric parameters. Approximately 40% of patients with obstructive sleep apnoea proved to have a retrognathic, dolichofacial appearance, which seems to contribute to obstructive apnoeas by retropositioning of the skeletal fixation for the muscles of the floor of the mouth and the tongue. Acoustic rhinometry for transnasal cross-sectional measurements of the upper airways is still under clinical trial. Whether it is a valuable supplement to cephalometric evaluation in the future will be mainly a question of software development.

[Surgical treatment of obstructive sleep apnea by modifying the facial skeleton with reference to cephalometric parameters]. / Die chirurgische Behandlung der obstruktiven Schlafapnoe durch gesichtsskelettverlagernde Eingriffe unter Berücksichtigung zephalometrischer Parameter.

UNLABELLED: Cephalometry: Morphologic alterations can be found in a great deal of patients with OSAS, predisposing to the rise of sleep apnea. In addition to preexisting investigations we developed a cephalometric analysis to judge these alterations in patients with OSAS. Comparing 160 patients to healthy people pharyngeal obstructions could be found in more than one third of the patients, usually combined with a retrognathic dolichofacial morphology. SURGICAL PROCEDURE: As successful treatment of our own patients shows, curing of obstructive sleep apnea is possible in respect of these cephalometric alterations. The basis of surgical treatment consists of surgical advancement of the mandible by sagittal split osteotomy and advancement of the maxilla by Le Fort I-osteotomy. Advancement surgery must be done in consideration of the morphologic alterations mentioned above. Additionally secondary procedures can be taken into account as genioplasty, soft-tissue-corrections or corrections of the upper airways.

[Mechanical/prosthetic protrusion of the mandible: effects on the pharynx]. / Mechanisch-/prothetische Unterkieferprotrusion: Auswirkungen auf den Pharynx.

Pharyngeal Effects: The protrusion of the mandible by prosthetic appliances ("Esmarch-prosthesis") may be a simple therapy for obstructive sleep apnea, but is effective only in rare cases. Aim of this study was the cephalometric investigation of pharyngeal changes by mechanic-/prosthetic mandibular protrusion in respect of the amount of protrusion. Cephalometric investigation was performed in 46 patients before and after mandibular protrusion, subdivided into 3 groups with protrusion of less than 7 mm, 7 to 10 mm, and more than 10 mm. A significant pharyngeal enlargement was found in all patients, but there was no correlation between the amount of protrusion and the amount of pharyngeal enlargement. Mandibular protrusion of more than 10 mm did not necessarily lead to more pharyngeal enlargement. A reliable prognosis of pharyngeal enlargement in respect of the amount of mandibular protrusion is not possible by cephalometric evaluation, even less a reliable prognosis of treatment success in respect of obstructive sleep apnea.

Nasal decongestion with imidazoline derivatives: acoustic rhinometry measurements.

OBJECTIVE: The objective of this single-blind study was to establish whether there are any differences between conventional imidazoline-containing nasal drops with regard to duration of action and decongestion potential. METHODS: Six different substances were each administered to 108 healthy volunteers (nine groups of 12 adults), respectively, in the concentration recommended for adults (and two also in that recommended for infants) over a period of 8 h in comparison with 0.9% NaCl. The volumetric measurement of the nasal lumen was conducted by means of acoustic rhinometry (Rhinoklack). RESULTS: The decongestive effect of all imidazoline preparations set in relatively uniformly, without any appreciable differences. After 20 min all the products exhibited approximately 60% of their maximum decongestive effect, which was achieved after approximately 40 min, having produced an increase in volume of approximately 20%. In contrast, in terms of duration of action, considerable differences between the individual products were to be discerned: indanazoline 0.118%, naphazoline 0.02% and tetryzoline 0.1% had no effect whatsoever after 4 h. Oxymetazoline 0.05% and 0.01%, xylometazoline 0.025% and 0.1%, and tramazoline 0.1264% still had an appreciable effect after 4 h, while after 8 h only oxymetazoline 0.05% and 0.01% still had a relevant decongestive effect. A rebound effect associated with reactive hyperaemia was observed after 8 h in all short-acting products (indanazoline, naphazoline, tetryzoline and tramazoline), which in the case of indanazoline was even associated with a reduction in the nasal lumen. Interestingly, there were no differences between the xylometazoline and oxymetazoline concentrations recommended for adults and those for infants in terms of efficacy. The low-dose concentrations of the preparations for infants appear to be sufficient to produce a satisfactory therapeutic effect.

[Obstructive sleep apnea syndrome caused by craniofacial abnormalities]. / Obstruktives Schlafapnoesyndrom auf dem Boden kraniofazialer Normabweichungen.

Patients with obstructive sleep apnoea syndrome frequently present distinct changes in the craniofacial skeleton that result in a structural narrowing of the pharynx and promote pharyngeal collapse during sleep. The evaluation of the clinical data of patients with and without craniofacial dysmorphia reveals that mean age, mean Broca index and the number of additional diseases is decreased in patients with craniofacial dysmorphia. Young patients or patients with normal weight and OSAS usually present such skeletal changes. The number of sleep-related breathing disorders and the extent of nocturnal desaturation are also decreased in the group of patients with dysmorphia. The structure of sleep is similarly disturbed in both groups. In most cases patients with severe obstructive sleep apnoea have normal cephalometric data.

Long-term results after maxillary advancement in patients with clefts.

In order to evaluate relapse tendencies after maxillary advancement, 31 patients were examined preoperatively, postoperatively, and 1 year postoperatively; 14 of whom had clefts of the lip, alveolus, and palate. Patients with maxillary deficiency were selected in a method that mere sagittal displacement was planned. Any patients with major vertical or transverse changes or additional mandibular surgery were excluded. Treatment consisted of maxillary advancement by Le Fort I osteotomy and miniplate fixation. Besides clinical examination, skeletal and dental changes were assessed cephalometrically. Results revealed a certain relapse tendency of the displacement in the noncleft group that compared favorably to the cleft group. This relapse is dependent on the amount of advancement. Despite minor differences, the two groups did not differ significantly based on maxillary advancement, so besides advancement surgery there must be another factor, cleft, to explain the different relapse tendencies between patients with and without clefts.