Numerical simulation of soft palate movement and airflow in human upper airway by fluid-structure interaction method

In this paper, the authors present airflow field characteristics of human upper airway and soft palate movement attitude during breathing. On the basis of the data taken from the spiral computerized tomography images of a healthy person and a patient with Obstructive Sleep Apnea-Hypopnea Syndrome （OSAHS）, three-dimensional models of upper airway cavity and soft palate are reconstructed by the method of surface rendering. Numerical simulation is performed for airflow in the upper airway and displacement of soft palate by fluid-structure interaction analysis. The reconstructed threedimensional models precisely preserve the original configuration of upper airways and soft palate. The results of the pressure and velocity distributions in the airflow field are quantitatively determined, and the displacement of soft palate is presented. Pressure gradients of airway are lower for the healthy person and the airflow distribution is quite uniform in the case of free breathing. However, the OSAHS patient remarkably escalates both the pressure and velocity in the upper airway, and causes higher displacement of the soft palate. The present study is useful in revealing pathogenesis and quantitative mutual relationship between configuration and function of the upper airway as well as in diagnosingdiseases related to anatomical structure and function of the upper airway.

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

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（LSaO2）] 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 BMI26（P0.05 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 BMI26.

Kimura's disease in soft palate with clinical and histopathological presentation: A case report

BACKGROUND Kimura’s disease is an inflammatory disease that is usually found in the deep lymph nodes of the head and neck.While rare,It is most frequently seen in young men.The oral cavity and salivary glands may also be involved.There are no reports on tumor occurring in soft palate.We have encountered a case of Kimura’s disease in the soft palate of an elderly woman.CASE SUMMARY A 63-year-old elderly Chinese woman with a slowly growing mass in the upper jaw was referred to our service.A biopsy to the mass was taken after the patient was referred to our service.The tumor was diagnosed as benign.We performed cervical lymph node puncture and partial surgical excision of the lesion.The tumor,which showed signs of marked follicular hyperplasia with follicles surrounded by eosinophils and lymphocytes,was located within the soft palate.Kimura’s disease was diagnosed after histopathologic examination of the resected tissue.The etiology of Kimura’s disease is not fully understood.One current model includes T-cells involvement with cytokines also playing a role.The patient was without evidence for recurrence of partially resected area 6 mo later.This report shows that Kimura’s disease is not limited to the head,neck,and salivary gland lymph nodes.We present a case of a tumor in soft palate.This location adds another possible site for consideration during the differential diagnoses of a slowly growing mass.CONCLUSION The present case illustrates a characteristic description of Kimura’s disease.This case highlights the main differences between Kimura’s disease and angiolymphoid hyperplasia with eosinophilia.

Identification of shared and unique gene families associated with oral clefts

Oral clefts, the most frequent congenital birth defects in humans, are multifactorial disorders caused by genetic and environmental factors. Epidemiological studies point to different etiologies underlying the oral cleft phenotypes, cleft lip(CL),CL and/or palate(CL/P) and cleft palate(CP). More than 350 genes have syndromic and/or nonsyndromic oral cleft associations in humans. Although genes related to genetic disorders associated with oral cleft phenotypes are known, a gap between detecting these associations and interpretation of their biological importance has remained. Here, using a gene ontology analysis approach, we grouped these candidate genes on the basis of different functional categories to gain insight into the genetic etiology of oral clefts. We identified different genetic profiles and found correlations between the functions of gene products and oral cleft phenotypes. Our results indicate inherent differences in the genetic etiologies that underlie oral cleft phenotypes and support epidemiological evidence that genes associated with CL/P are both developmentally and genetically different from CP only, incomplete CP, and submucous CP. The epidemiological differences among cleft phenotypes may reflect differences in the underlying genetic causes. Understanding the different causative etiologies of oral clefts is important as it may lead to improvements in diagnosis, counseling, and prevention.

Effects of Denture Removal on Expiratory Upper Airway Patency during Mask Ventilation in Complete Denture Wearers under General Anesthesia

Background: Some anesthetized patients present with expiratory airway obstruction (EAO) during mask ventilation (MV). EAO may occur more frequently among edentulous patients for whom a firmer grip of the mask and the mandible is needed to avoid gas leakage. We compared EAO grades before and after denture removal and identified predictors of EAO during MV in edentulous patients. Methods: One hundred and eight denture-wearing edentulous patients were anesthetized, their mouths were wrapped with film, their nasal masks and mandibles were held with two hands, and their lungs were ventilated in a pressure-controlled mode. Their dentures were subsequently removed, mouths were re-wrapped, and nasal MV was reapplied. EAO was graded based on capnography waveforms as follows: Grade I, normal waveform (no obstruction);II, loss of the alveolar plateau of the waveform (partial obstruction);and III, no waveform (total obstruction). EAO grades were compared before and after denture removal. Predictive demographic variables for occurrence of total EAO were identified using a multivariate analysis. Results: The proportions of Grades I, II, and III were 43.5%, 26.9%, and 29.6% when dentures were worn and 35.2%, 15.7%, and 49.1%, respectively, when dentures were removed. A significant difference was observed in EAO grades before and after denture removal (P = 0.000034). Age ≥ 75 years (adjusted odds ratio 3.41;95% confidence interval 1.31 - 8.87;P = 0.012) and body mass index ≥ 25 kg/m2 (adjusted odds ratio 2.61;95% confidence interval 1.07 - 6.40;P = 0.036) were independently associated with an increased incidence of total EAO in patients with their dentures removed. Conclusion: Denture removal impaired expiratory upper airway patency in edentulous patients, particularly in older or obese patients, during MV.

Preparation and evaluation of mucoadhesive bio-flexy films from Cocos nucifera biopolymer using Tiagabine moiety

This research work deals with formulation and evaluation of nanosized Tiagabine loaded bio-flexy films consisting of Cocos nucifera biopolymer(isolated from coconut kernels).Prepared formulations were administered through soft palatal route for brain targeting for epilepsy treatment.Soft palate,part of oral mucosa serves as novel drug delivery platform and mucoadhesive site for systemic drug delivery.It provides sustained and controlled drug delivery system,does not interfere with patient’s regular activities like talking,eating,drinking,etc.It bypasses first-pass metabolism in the liver,reduces dose frequency and minimizes drug’s side effects.Tiagabine,anticonvulsant drug possesses t1/2:7-9 h(low);Protein binding:96%;Water solubility:22 mg/L,acts as selective gamma amino butyric acid(GABA)reuptake inhibitor.Cocos nucifera biopolymer used as bio-excipient to prepare bio-flexy films due to its biodegradability,biocompatibility,non-toxicity,non-irritantancy on soft palatal surface along with inbuilt filmability,mucoadhesive properties.Nanosized drug loaded bio-flexy films were formulated using standard solvent casting method.Bio-flexy films were prepared using varying ratios of nanosized Tiagabine:isolated Cocos nucifera biopolymer(FCT1-FCT6).These prepared formulations were compared with same ratios of nanosized Tiagabine:sodium carboxyl methyl cellulose standard polymer flexy films(FET1-FET6).The%yield of Cocos nucifera biopolymer was found to be 10.2±0.04%.Thickness of nanosized Tiagabine loaded bio-flexy films containing Cocos nucifera biopolymer(FCT1-FCT6)was ranging from 0.026±0.04 mm to 0.040±0.02 mm;Folding endurance:84-107;Surface pH:7.01±0.04 to 7.01±0.02;Weight uniformity:0.012±0.04 to 0.020±0.02;Drug content uniformity:69.5±0.35%to 72.9±0.26%;Swelling percentage:65±0.5%to 73±0.2%;Percentage moisture uptake(PTU):2.0±0.14%to 2.8±0.12%;Mucoadhesivity:20-90 min;Mucoretentivity:60-180 min.The drug release pattern for formulations FCT1-FCT6 containing Cocos nucifera biopolymer based on the T50%and T80%was found to be FCT1(1:0.5)>FCT5(1:6)>FCT3(1:3)>FCT2(1:1)>FCT4(1:5)>FCT6(1:10).Based on all above-mentioned evaluation parameters,FCT1(containing Tiagabine:Cocos nucifera biopolymer(1:0.5))bio-flexy film having R2=0.9221,Higuchi matrix as best fit model,follows anomalous transport release mechanism,T50%:38.45 h.,T80%:41.20 h.using BITS Software 1.12.Stability study revealed stable formulations.Prepared formulations were suitable for soft palatal delivery.

OSAHS的外科治疗策略

近年来，阻塞性睡眠呼吸暂停低通气综合征（OSAHS）由于发病率高，危害性大而受到广泛关注。该病是一种累及多系统并造成多器官损害的睡眠呼吸疾病，是高血压、冠心病、心律失常、脑卒中等多种疾病的独立危险因素，并可能是糖尿病、性功能障碍等多种疾病的共同危险因素。

软腭缺损修复研究进展

软腭缺损常见于恶性肿瘤切除术后,较大的缺损不仅严重影响患者发音和吞咽功能,还严重影响生活质量和心理健康.由于软腭解剖结构与功能的特殊性,其缺损修复是临床上一个难题.软腭缺损至今已发展出多种皮瓣修复方式,包括前臂游离皮瓣、颊肌黏膜瓣、岛状腭瓣、舌瓣、颏下皮瓣、前额皮瓣以及联合皮瓣等,但各有优缺点,本文将围绕软腭缺损修复的现状及研究进展进行综述.