Isolated velopalatine paralysis associated with parvovirus B19 infection.
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A case of isolated velopalatine paralysis in an 8-year-old boy is presented. The symptoms were sudden-onset of nasal speech, regurgitation of liquids into the nose and dysphagia. Brain MRI and cerebrospinal fluid examination were normal. Infectious serologies disclosed an antibody arrangement towards parvovirus B19 that was typical of recent infection. In the absence of other positive data, the possibility of a correlation between the tenth nerve palsy and parvovirus infection is discussed. (+info)
Extent and localization of changes in upper airway caliber with varying concentrations of sevoflurane in children.
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BACKGROUND: Previous studies in humans suggest that inhibition of upper airway muscle activity is independent of the dose of inhalational anesthesia. Whether a dose-independent relation applies to changes in airway caliber is unknown. The authors sought to evaluate the configurational changes that lead to upper airway narrowing during inhalational anesthesia with sevoflurane and to determine whether these changes are dose dependent within a clinically relevant dose range. METHODS: Fifteen children undergoing elective magnetic resonance imaging of the brain were studied. Magnetic resonance images of the upper airway were acquired at sevoflurane concentrations of 0.5, 1.0, and 1.5 minimum alveolar concentration (MAC), administered in random sequence. At least 15 min was allowed for equilibration of inspired and alveolar partial pressures of sevoflurane. Images were acquired in early expiration at the level of the soft palate, base of the tongue, and tip of the epiglottis. Airway cross-sectional area (CSA), anteroposterior, and transverse dimension were determined using image-analysis software. RESULTS: At each anatomical level, pharyngeal CSA decreased progressively with increasing depth of sevoflurane anesthesia (P < 0.001). Increasing the sevoflurane concentration from 0.5 to 1.0 MAC reduced airway CSA by 13-18%, and a further increase to 1.5 MAC resulted in an overall 28-34% reduction in CSA. The reduction in CSA was predominantly due to a decrease in anteroposterior dimension. CONCLUSIONS: Increasing the depth of sevoflurane anesthesia resulted in a relatively uniform reduction in pharyngeal caliber at each anatomical level studied. The effect of sevoflurane on upper airway caliber is dose dependent. (+info)
Evaluation of cross-section airway configuration of obstructive sleep apnea.
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Upper airway imaging techniques can be useful to identify the exact location and nature of the obstruction in obstructive sleep apnea (OSA) patients. Ten OSA patients and 10 non-OSA control subjects were imaged using cone-beam computed tomography (NewTom QR-DVT9000) to compare their upper airway structure. The OSA subjects presented higher BMI (OSA: 29.5 +/- 9.05 kg/m(2); non-OSA: 23.1 +/- 3.05 kg/m(2) [P = .034]), lower total volume (mm(3)) of the airway (OSA: 4868.4 +/- 1863.9; non-OSA: 6051.7 +/- 1756.4 [P = .054]), statistically significantly smaller anterior-posterior dimension (mm) of the minimum cross-section segment (OSA: 4.6 +/- 1.2; non-OSA: 7.8 +/- 3.31 [P = .009]), and smaller minimum cross-section area (OSA: 45.8+/-17.5 mm(2); non-OSA: 146.9 +/- 111.7 mm(2) [P = .011]) positioned below the occlusal plane in 70% of the cases (OSA:7 out of 10; non-OSA: 5 out of 10 [P = .030]). The OSA group presented a concave or elliptic shaped airway and the non-OSA group presented a concave, round, or square shaped airway. (+info)
Gene expression analysis reveals that formation of the mouse anterior secondary palate involves recruitment of cells from the posterior side.
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Cleft palate is a common birth defect caused by disruptions in secondary palate development. Anterior-posterior (A-P) regional specification plays a critical role in palate development and fusion. Previous studies have shown that at the molecular level, the anterior palate can be defined by the expression of Shox-2 and the posterior palate by Meox-2 expression in certain mouse strains. Here, we have extended previous studies by performing a more detailed analysis of these genes during mouse palate development. We found that the expression patterns of Shox-2 and Meox-2 are dynamic during palate development. At embryonic day 12.5 (E12.5), Shox-2 expression is localized to the anterior end and its expression domain covers less than 25% of the length of the palate shelf. The Shox-2 expression domain then gradually expands towards the posterior end and ultimately occupies more than 60% of the palate shelf by E14.5. The expansion of the Shox-2 domain may involve induction of Shox2 expression in additional cells. Reciprocally, the Meox-2 expression domain at E12.5 covers a large portion of the palate shelf, a region more than 70% of the entire palate, but then regresses to the posterior 25% by E14.5. This regression is likely caused by the repression of Meox-2 expression in certain Meox2 expressing cells, rather than the cessation of cell proliferation. Therefore, certain Meox-2 positive "primitive posterior cells" are differentiated/converted into Shox-2 positive "definitive anterior cells" during A-P regional specification. (+info)
Contraction-induced injury to single permeabilized muscle fibers from normal and congenitally-clefted goat palates.
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OBJECTIVE: Levator veli palatini muscles from normal palates of adult humans and goats are predominantly slow oxidative (type 1) fibers. However, 85% of levator veli palatini fibers from cleft palates of adult goats are physiologically fast (type 2). This fiber composition difference between cleft and normal palates may have implications in palatal function. For limb muscles, type 2 muscle fibers are more susceptible to lengthening contraction-induced injury than are type 1 fibers. We tested the hypothesis that, compared with single permeabilized levator veli palatini muscle fibers from normal palates of adult goats, those from cleft palates are more susceptible to lengthening contraction-induced injury. INTERVENTIONS: Congenital cleft palates were the result of chemically-induced decreased movement of the fetal head and tongue causing obstruction of palatal closure. Each muscle fiber was maximally activated and lengthened. OUTCOME MEASURES: Fiber type was determined by contractile properties and gel electrophoresis. Susceptibility to injury was assessed by measuring the decrease in maximum force following the lengthening contraction, expressed as a percentage of the initial force. RESULTS: Compared with fibers from normal palates that were all type 1 and had force deficits of 23 +/- 1%, fibers from cleft palates were all type 2 and sustained twofold greater deficits, 40 +/- 1% (p = .001). CONCLUSION: Levator veli palatini muscles from cleft palates of goats contain predominantly type 2 fibers that are highly susceptible to lengthening contraction-induced injury. This finding may have implications regarding palatal function and the incidence of velopharyngeal incompetence. (+info)
Snoring and obstructive sleep apnea.
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The number of patients who suffer from snoring and sleep apnea in Iran has been increasing in proportionate to the rest of the world as the prevalence of obesity has soared within the last two decades. This pandemic obesity is blamed on consumption of more energy-dense, nutrient-poor foods with high levels of sugar and saturated fats. Obesity is one of the major contributing factors of obstructive sleep apnea. The number of people snoring in Iran is not well established, but since many years ago this bizarre behaviour was looked upon as an annoying sound that some people have and it was thought that they have to live with it. It was not until early twentieth century that scientists began to relate an association between snoring, obesity, and sleep-related disorders. At present time, it is well documented and universally agreed that snoring as well as sleep apnea are far more prevalent in societies and can lead to other serious illnesses including heart attack, stroke, and even nocturnal death. Obstructive sleep apnea is a term used to describe cession of breathing while sleep for a period of 10 seconds or more and repeated over five times per hour of sleep. In this article, we review various methods of surgical treatments and the long-term relapse potential for each. (+info)
Use of computational modeling to predict responses to upper airway surgery in obstructive sleep apnea.
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OBJECTIVES: Despite the well-recognized consequences of obstructive sleep apnea (OSA), its treatment remains unsatisfactory. Therapeutic strategies are complicated by often poor adherence in the case of continuous positive airway pressure or the highly variable efficacy in the case of many upper airway surgeries. Computational models of the upper airway using finite element analysis to simulate the effects of various anatomic and physiologic manipulations on pharyngeal mechanics could be helpful in predicting surgical success. STUDY DESIGN: Computational and physiologic study. METHODS: Using representative OSA magnetic resonance images and experimentally measured upper airway dilator muscle activities, we developed a working two-dimensional and a partial three-dimensional model of the upper airway. RESULTS: As predicted from experimental measurements, the OSA model airway has a closing pressure of -2 cm H2O. Manipulations such as palatal stiffening, palatal resection, and tongue stiffening all have demonstrable effects on pharyngeal mechanics. We have also developed a partial three-dimensional OSA model in which we simulate the mechanics of the pharyngeal airway in the mid-sagittal and parasagittal slices, spanning more than 1 inch in thickness. Using this model, we have observed important effects of tongue and palatal stiffening on anteroposterior collapse of the pharyngeal airway. CONCLUSIONS: Our data suggest that computational modeling is feasible and can be used to generate hypotheses for subsequent clinical trials regarding anatomic manipulations in OSA. We further believe that the goal of individualizing OSA therapy on the basis of underlying mechanisms could be facilitated by computational modeling. (+info)
Sialometaplasia of the soft palate in a 2-year-old girl.
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A case of sialometaplasia of the soft palate is reported in a 2-year-old girl 3 months after she had an adenoidectomy. Dental practitioners should be aware of the possible causes of intraoral swellings in both children and adults. The appearance of some conditions in children may differ from their characteristic appearance in adults. Necrotizing sialometaplasia may appear as an aggressive-looking lesion in an adult, possibly resembling squamous cell carcinoma. In the young patient reported here, frank necrosis was not evident from clinical or histological examination. Necrosis may not be part of the presentation of sialometaplasia in such young children. (+info)