THE DISTRIBUTIONS OF AIRFLOW WITHIN THE UPPER AIRWAY AND POSTURE CHANGES OF SOFT PALATE IN PATIENTS WITH OSAHS AFTER NASAL STRUCTURAL CORRECTION

2018 ◽  
Vol 30 (02) ◽  
pp. 1850017
Author(s):  
Gang Wang ◽  
Chi Yu ◽  
Ying Wang

Nasal obstruction frequently has been associated with obstructive sleep apnea-hypopnea syndrome (OSAHS). Based on the CT data before and after the operation of the three Chinese patients, 3D numerical models involving the upper airway and the soft palate are established. Computational modeling for inspiration and expiration was performed by using fluid–structure interaction (FSI) method. The airflow characteristics such as velocity and pressure drop, and displacement distribution of soft palate are selected for comparison. The distribution of airflow in the upper airway and the motion changes of the soft palate are analyzed quantitively before and after the surgery. From the results, that the inner connection between the both upper and lower part of the upper airway is very complex due to the individual difference of own unique feature of upper airway. Whether can it treat OSAHS only through nasal surgery, which depends primarily on the improvement of ventilation in upper part of upper airway giving a beneficial effect on the lower part (especially in the velopharyngeal region). The simulation results correspond with the monitoring results of polysomnography (PSG) and the patient's presenting complaint. Moreover, the mechanical parameters obtained by numerical simulation can support the improvement of OSAHS symptoms after surgery, which provides quantitative and referential evidence for further study the role of nasal structure in OSAHS and the treatment effect of nasal surgery on OSAHS.

2003 ◽  
Vol 95 (5) ◽  
pp. 1761-1766 ◽  
Author(s):  
Jason P. Kirkness ◽  
Melanie Madronio ◽  
Rosie Stavrinou ◽  
John R. Wheatley ◽  
Terence C. Amis

Lowering surface tension (γ) of upper airway lining liquid (UAL) reduces upper airway opening (anesthetized humans) and closing (anesthetized rabbits) pressures. We now hypothesize that in sleeping obstructive sleep apnea hypopnea syndrome (OSAHS) patients lowering γ of UAL will enhance upper airway stability and decrease the severity of sleep-disordered breathing. Nine OSAHS patients [respiratory disturbance index (RDI): 49 ± 8 (SE) events/h, diagnostic night] participated in a two-part, one-night, polysomnography study. In the first part, upper airway closing pressures (during non-rapid eye movement sleep, Pcrit) were measured and samples of UAL (awake) were obtained before and after 2.5 ml of surfactant (Exosurf, Glaxo Smith Kline) was instilled into the posterior pharynx. The γ of UAL was determined with the use of the “pull-off” force technique. In the second part, subjects received a second application of 2.5 ml of surfactant and then slept the remainder of the night (205 ± 30 min). Instillation of surfactant decreased the γ of UAL from 60.9 ± 3.1 mN/m (control) to 45.2 ± 2.5 mN/m (surfactant group) ( n = 9, P < 0.001). Pcrit decreased from 1.19 ± 1.14 cmH2O (control) to -0.56 ± 1.15 cmH2O (surfactant group) ( n = 7, P < 0.02). Compared with the second half of diagnostic night, surfactant decreased RDI from 51 ± 8 to 35 ± 8 events/h ( n = 9, P < 0.03). The fall in RDI (ΔRDI) correlated with the fall in γ of UAL (Δγ) (ΔRDI = 1.8 × Δγ, r = 0.68, P = 0.04). Hypopneas decreased ∼50% from 42 ± 8 to 20 ± 5 events/h ( n = 9, P < 0.03, paired t-test). The γ of UAL measured the next morning remained low at 49.5 ± 2.7 mN/m ( n = 9, P < 0.001, ANOVA, compared with control). In conclusion, instillation of surfactant reduced the γ of UAL in OSAHS patients and decreased Pcrit and the occurrence of hypopneas. Therapeutic manipulation of γ of UAL may be beneficial in reducing the severity of sleep-disordered breathing in OSAHS patients.


SLEEP ◽  
2019 ◽  
Vol 43 (5) ◽  
Author(s):  
Liyue Xu ◽  
Brendan T Keenan ◽  
Andrew S Wiemken ◽  
Luqi Chi ◽  
Bethany Staley ◽  
...  

Abstract Study Objectives This study evaluated differences in upper airway, soft tissues and craniofacial structures between Asians from China and Europeans from Iceland with OSA using three-dimensional magnetic resonance imaging (MRI). Methods Airway sizes, soft tissue volumes, and craniofacial dimensions were compared between Icelandic (N = 108) and Chinese (N = 57) patients with oxygen desaturation index (ODI) ≥ 10 events/h matched for age, gender, and ODI. Mixed effects models adjusting for height or BMI and residual differences in age and ODI were utilized. Results In our matched sample, compared to Icelandic OSA patients, Chinese patients had smaller BMI (p &lt; 0.0001) and neck circumference (p = 0.011). In covariate adjusted analyses, Chinese showed smaller retropalatal airway size (p ≤ 0.002), and smaller combined soft tissues, tongue, fat pads, and pterygoid (all p ≤ 0.0001), but male Chinese demonstrated a larger soft palate volume (p ≤ 0.001). For craniofacial dimensions, Chinese demonstrated bigger ANB angle (p ≤ 0.0196), differently shaped mandibles, including shorter corpus length (p &lt; 0.0001) but longer ramus length (p &lt; 0.0001), and a wider (p &lt; 0.0001) and shallower (p ≤ 0.0001) maxilla. Conclusions Compared to Icelandic patients of similar age, gender and ODI, Chinese patients had smaller retropalatal airway and combined soft tissue, but bigger soft palate volume (in males), and differently shaped mandible and maxilla with more bony restrictions. Results support an ethnic difference in upper airway anatomy related to OSA, which may inform targeted therapies.


ORL ◽  
2021 ◽  
pp. 1-8
Author(s):  
Lifeng Li ◽  
Demin Han ◽  
Hongrui Zang ◽  
Nyall R. London

<b><i>Objective:</i></b> The purpose of this study was to evaluate the effects of nasal surgery on airflow characteristics in patients with obstructive sleep apnea (OSA) by comparing the alterations of airflow characteristics within the nasal and palatopharyngeal cavities. <b><i>Methods:</i></b> Thirty patients with OSA and nasal obstruction who underwent nasal surgery were enrolled. A pre- and postoperative 3-dimensional model was constructed, and alterations of airflow characteristics were assessed using the method of computational fluid dynamics. The other subjective and objective clinical indices were also assessed. <b><i>Results:</i></b> By comparison with the preoperative value, all postoperative subjective symptoms statistically improved (<i>p</i> &#x3c; 0.05), while the Apnea-Hypopnea Index (AHI) changed little (<i>p</i> = 0.492); the postoperative airflow velocity and pressure in both nasal and palatopharyngeal cavities, nasal and palatopharyngeal pressure differences, and total upper airway resistance statistically decreased (all <i>p</i> &#x3c; 0.01). A significant difference was derived for correlation between the alteration of simulation metrics with subjective improvements (<i>p</i> &#x3c; 0.05), except with the AHI (<i>p</i> &#x3e; 0.05). <b><i>Conclusion:</i></b> Nasal surgery can decrease the total resistance of the upper airway and increase the nasal airflow volume and subjective sleep quality in patients with OSA and nasal obstruction. The altered airflow characteristics might contribute to the postoperative reduction of pharyngeal collapse in a subset of OSA patients.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Hui-Wei Feng ◽  
Tao Jiang ◽  
Hong-Ping Zhang ◽  
Zhe Wang ◽  
Hai-Ling Zhang ◽  
...  

Objective. The aim of this study was to compare the differences in thyroid hormone, intelligence, attention, and quality of life (QoL) of children with obstructive sleep apnea hypopnea syndrome (OSAHS) before and after endoscopic adenoidectomy.Method. A total of 35 OSAHS children (21 males and 14 females with a mean age of6.81±1.08years) were included in this study for analyzing the levels of thyroid hormone, intelligence, attention, and QoL. There were 22 children underwent endoscopic adenoidectomy with bilateral tonsillectomy (BT), while the other 13 children who underwent endoscopic adenoidectomy without bilateral tonsillectomy without BT.Results. Our results revealed no significant difference in serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH) levels in OSAHS children before and after endoscopic adenoidectomy (allP>0.05). However, there were significant differences in full-scale intelligence quotient (FIQ) (92.45±5.88versus106.23±7.39,P<0.001), verbal intelligence quotient (VIQ) (94.17±15.01versus103.91±9.74,P=0.006), and performance intelligence quotient (PIQ) (94.12±11.04versus104.31±10.05,P=0.001), attention (98.48±8.74versus106.87±8.58,P<0.001), and total OSA-18 scores (87.62±17.15versus46.61±10.15,P<0.001) between before and after endoscopic adenoidectomy in OSAHS children.Conclusion. Our findings provided evidence that the intelligence, attention, and QoL of OSAHS children may be significantly improved after endoscopic adenoidectomy.


2008 ◽  
Vol 118 (2) ◽  
pp. 360-362 ◽  
Author(s):  
Mihai Mihaescu ◽  
Shanmugam Murugappan ◽  
Ephraim Gutmark ◽  
Lane F. Donnelly ◽  
Maninder Kalra

SLEEP ◽  
2021 ◽  
Author(s):  
Arun Sebastian ◽  
Peter A Cistulli ◽  
Gary Cohen ◽  
Philip de Chazal

Abstract Study objectives Acoustic analysis of isolated events and snoring by previous researchers suggests a correlation between individual acoustic features and individual site of collapse events. In this study, we hypothesised that multi-parameter evaluation of snore sounds during natural sleep would provide a robust prediction of the predominant site of airway collapse. Methods The audio signals of 58 OSA patients were recorded simultaneously with full night polysomnography. The site of collapse was determined by manual analysis of the shape of the airflow signal during hypopnoea events and corresponding audio signal segments containing snore were manually extracted and processed. Machine learning algorithms were developed to automatically annotate the site of collapse of each hypopnoea event into three classes (lateral wall, palate and tongue-base). The predominant site of collapse for a sleep period was determined from the individual hypopnoea annotations and compared to the manually determined annotations. This was a retrospective study that used cross-validation to estimate performance. Results Cluster analysis showed that the data fits well in two clusters with a mean silhouette coefficient of 0.79 and an accuracy of 68% for classifying tongue/non-tongue collapse. A classification model using linear discriminants achieved an overall accuracy of 81% for discriminating tongue/non-tongue predominant site of collapse and accuracy of 64% for all site of collapse classes. Conclusions Our results reveal that the snore signal during hypopnoea can provide information regarding the predominant site of collapse in the upper airway. Therefore, the audio signal recorded during sleep could potentially be used as a new tool in identifying the predominant site of collapse and consequently improving the treatment selection and outcome.


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