Evaluation of airway obstruction at soft palate level in male patients with obstructive sleep apnea/hypopnea syndrome: Dynamic 3-dimensional CT imaging of upper airway

Abstract

This study examined the dynamic characteristics of upper airway collapse at soft palate level in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS) by using dynamic 3-Dimensional (3-D) CT imaging. A total of 41 male patients who presented with 2 of the following symptoms, i.e., daytime sleepiness and fatigue, frequent snoring, and apnea with witness, were diagnosed as having OSAHS. They underwent full-night polysomnography and then dynamic 3-D CT imaging of the upper airway during quiet breathing and in Muller's maneuver. The soft palate length (SPL), the minimal cross-sectional area of the retropalatal region (mXSA-RP), and the vertical distance from the hard palate to the upper posterior part of the hyoid (hhL) were compared between the two breathing states. These parameters, together with hard palate length (HPL), were also compared between mild/moderate and severe OSAHS groups. Association of these parameters with the severity of OSAHS [as reflected by apnea hypopnea index (AHI) and the lowest saturation of blood oxygen (LSaO(2))] was examined. The results showed that 31 patients had severe OSAHS, and 10 mild/moderate OSAHS. All the patients had airway obstruction at soft palate level. mXSA-RP was significantly decreased and SPL remarkably increased during Muller's maneuver as compared with the quiet breathing state. There were no significant differences in these airway parameters (except the position of the hyoid bone) between severe and mild/moderate OSAHS groups. And no significant correlation between these airway parameters and the severity of OSAHS was found. The position of hyoid was lower in the severe OSAHS group than in the mild/moderate OSAHS group. The patients in group with body mass index (BMI)≥26 had higher collapse ratio of mXSA-RP, greater neck circumference and smaller mXSA-RP in the Muller's maneuver than those in group with BMI<26 (P<0.05 for all). It was concluded that dynamic 3-D CT imaging could dynamically show the upper airway changes at soft palate level in OSAHS patients. All the OSAHS patients had airway obstruction of various degrees at soft palate level. But no correlation was observed between the airway change at soft palate level and the severity of OSAHS. The patients in group with BMI≥26 were more likely to develop airway obstruction at soft palate level than those with BMI<26.

CBCT in orthodontics: assessment of treatment outcomes and indications for its use

“…122 While CBCT is generally used to image mineralized tissues, it can also be used to accurately image the airway, which allows clinicians to measure cross-sectional area, minimum cross section and total volume of the patient's airway [123][124][125] (Figure 11). Initial investigations on airway patency, function and disorders utilizing CBCT have provided preliminary answers, including dimensions of normal airway anatomy in adults, 122,126 relationship Dentomaxillofac Radiol, 44,20140282 birpublications.org/dmfr of 2D to 3D measurements, 127 differences in airway morphology in subjects with OSA and non-OSA, [128][129][130] the effects of extractions on 3D pharyngeal volume and structure, 131 and the consequences of RME [132][133][134][135] and orthognathic surgery on airway dimensions. 136,137 Several of these studies show no relationships between 2D linear dimensions and 3D cross-sectional areas of the airway, which suggests that the use of 2D data may not be valid for assessing airway patency.…”

The Differences in Homocysteine Level between Obstructive Sleep Apnea Patients and Controls: A Meta-Analysis

“…Obstructive sleep apnea (OSA), characterized by repetitive hypopneas and apneas during sleep due to upper airway obstruction [1], [2], affects about 26% of the adults and has been gaining public awareness [3]. The relationship between OSA and cardiovascular conditions has been studied for decades, and OSA has been identified as an independent risk factor for cardiovascular diseases [4], [5].…”

Changes in pharyngeal airway space and soft tissue after maxillary advancement and bimaxillary surgery

“…The presence of other predisposing factors for the obstructive sleep apnea syndrome must also be observed in candidates for mandibular setback surgery, such as overweight, short neck, tongue volume, wide uvula and excessive amount of soft tissue around the nasopharyngeal region, which may favor the development of the syndrome [19][20] . In addition, other factors such as the facial type and unsatisfactory neuromuscular adaptation should also be considered 15 .…”