Evaluation of the upper airway

Three-dimensional evaluation of the effects of Bionator and Forsus appliances on oropharyngeal airway volume in patients with mandibular retrognathia

OBJECTIVE

To evaluate whether there is a difference between the effects of Bionator and Forsus appliances on airway volume.

METHODS

Forty patients with mandibular retrognathia were divided into two groups. The Bionator appliance was applied to Group 1, while the Forsus FRD EZ2 appliance was applied to Group 2. Three-dimensional images were captured before and after functional appliance use in both groups. Dolphin 3D software was used for airway measurements.

RESULTS

No statistically significant difference was found between the groups in terms of volumetric and area measurements. There was a statistically significant difference between the minimum axial T and O-N border T measurements of the groups.

CONCLUSION

The use of functional appliances may contribute to an increase in oropharyngeal airway dimensions, but there was no difference between the Bionator and Forsus groups in terms of volumetric measurements.

Pharyngeal airway, hyoid bone, and soft palate changes after Class II treatment with Twin-block and Forsus appliances during the postpeak growth period

INTRODUCTION

This study aimed to compare cephalometrically the pharyngeal airway, hyoid bone, and soft palate (SP) changes after Class II malocclusion treatments using Twin-block (TWB) and Forsus Fatigue Resistant Device (FFRD) (3M Unitek Corp, 3M Dental Products, Monrovia, Calif) during the postpeak growth period.

METHODS

Forty-two patients with Class II malocclusion treated during the postpeak growth period were randomly and retrospectively included in this study. These patients were divided into 2 treatment groups: TWB and FFRD. The skeletal, dental, pharyngeal airway, hyoid bone position, and SP measurements were obtained from the lateral cephalometric radiographs taken at the beginning and at the end of the treatment. Paired-samples and independent-samples t tests were used for the intragroup and intergroup comparisons, respectively.

RESULTS

In the TWB group, the SNB (°), Md1-NB (mm), Md1-NB (°), and McNamara upper and lower pharyngeal airway dimensions significantly increased, whereas the ANB (°), AD1-Ba (mm), AD2-H (mm), adenoidal nasopharyngeal area, and SP angle decreased (P < 0.05). In the FFRD group, the SNB (°), Md1-NB (mm), Md1-NB (°), Ptm-Ba (mm), and McNamara upper airway dimensions significantly increased, whereas the ANB (°), AD2-H (mm), and interincisor angle decreased (P < 0.05). Moreover, there were statistically significant differences in the Md1-NB angles and SP thicknesses between the 2 groups (P < 0.05).

CONCLUSIONS

The effects of TWB and FFRD treatment on the airway during the postpeak growth period were similar. However, the FFRD caused a greater mandibular incisor protrusion.

Assessment and causes of stridor

Stridor is a variably pitched respiratory sound, caused by abnormal air passage during breathing and often is the most prominent sign of upper airway obstruction. It is usually heard on inspiration (typically resulting from supraglottic or glottic obstruction) but also can occur on expiration (originating from obstruction at or below glottic level and/or severe upper airway obstruction). Stridor due to congenital anomalies may exist from birth or may develop within days, weeks or months. Various congenital and acquired disorders prevail in neonates, infants, children, and adolescents, and have to be distinguished. History, age of the child and physical examination together often allow a presumptive diagnosis. Further investigations may be necessary to establish a definite diagnosis, and flexible airway endoscopy is the diagnostic procedure of choice in most circumstances ("stridor is visible").

Submucosal Hemangioma of the Trachea in an Infant: Diagnosis and Follow-Up with 3D-CT/Bronchoscopy

Introduction:

Case Presentation:

Conclusions:

Management of acute severe upper airway obstruction in children

There are many causes of acute severe upper airway obstruction (UAO) in children. The timing of symptom onset and the presence of fever will help to distinguish infectious from non-infectious conditions. Signs and symptoms from congenital malformations often present at birth but may also develop over time. The most common cause of UAO in children is croup. Choking on a foreign body also occurs relatively frequently. Evaluation of the child with UAO starts with a detailed history followed by a thorough physical examination, including an assessment of severity. Severe airway obstruction will result in respiratory failure. This situation requires an immediate response. A child with partial airway obstruction may initially have an adequate airway. However, this situation can deteriorate rapidly. Therefore, providing supportive care and mobilizing resources for definitive airway management may be the most appropriate interventions.

Analysis of tidal breathing flow volume loop in dogs with tracheal masses

OBJECTIVES

To investigate whether there are any changes in the tidal breathing flow volume loop (TBFVL) in calm, non-dyspnoeic dogs with intratracheal masses.

METHODS

We compared 4 dogs with intratracheal masses (group 1) with 10 healthy dogs (group 2). Routine clinical and laboratory examinations of the dogs were unremarkable, except for episodic upper respiratory obstructive signs in the dogs in group 1. Lateral radiography of the neck and thorax showed that group 1 dogs had masses that appeared to protrude into the tracheal lumen. Tracheoscopy and surgery or necropsy was performed to confirm the presence of the mass. Arterial blood gas and TBFVL analysis was carried out in all dogs to assess respiratory status.

RESULTS

The shape of the TBFVL for dogs in group 1 was narrower and ovoid compared with that for the group 2 dogs. Tidal volume and expiratory and inspiratory times were significantly reduced, whereas the respiratory rate was increased for dogs in group 1 compared with dogs in group 2. Arterial blood gas analysis was unremarkable for all dogs.

CONCLUSIONS

TBFVL is a non-invasive technique that is easy to perform and well tolerated by dogs. In the absence of abnormalities detected by routine diagnostic evaluations and arterial blood gas analysis in dogs with intratracheal masses, the TBFVL contributes to the definition of the physiologic status of the airways at the time of testing, and results suggests that these dogs breathe quite normally when they are calm and non-dyspnoeic.

Lateral X-ray view of the skull for the diagnosis of adenoid hypertrophy: a systematic review

OBJECTIVES

Many studies have been developed aiming to reveal the usefulness of cavum X-rays and telerradiographies as diagnostic tools for the detection of upper airway obstruction due to adenoid hypertrophy. However, the scientific literature is diverse and controversial. Therefore, a systematic review is proposed; with the objective to determine the diagnosis value of lateral X-ray view of the skull regarding adenoid hypertrophy.

METHODS

Searching was conducted on Pubmed, Lilacs, Cochrane Library, Embase, and Web of Knowledge databases; and was restricted to studies published in English, Portuguese or Spanish languages, carried out on humans under 18 years of age. All the obtained publications were first submitted to a pre-selection, and then, full-texts (n=66) were analyzed and selected by independent examiners. The resultant studies (n=11) were systematically and critically analyzed, and qualified according to QUADAS (Quality Assessment of Diagnostic Accuracy Studies) questionnaire, an assessment tool designed to qualify diagnostic tests accuracy studies.

RESULTS

Searching and selection procedures generated 11 studies which were considered adequate to be systematically analyzed. Accordingly, large variation was observed concerning the evaluation methods of radiographic and fibronasoendoscopic exams, and the sample characteristics. Additionally, little amount of scientific evidences could be provided, since few radiographic variables were analyzed simultaneously. Moreover, assessment methods were, at most, subjective or poorly described. QUADAS application revealed other significant limitations related to the sampling, such as inadequate spectrum of the investigated "disease" (adenoid hypertrophy), and poor report of the subjects' enrollment and participation process. Further, QUADAS revealed inadequacies regarding methodological features, including poor description of the radiographic exams and assessment methods. In addition, it was also shown that most of the studies did not specify the moment in clinical time when both exams were performed; neither reported a strategy of "blindness" by the examiners.

CONCLUSIONS

Despite such limitations, the majority of the resultant data indicates that lateral X-rays might be considered somewhat useful, even though it could not be clearly demonstrated. Future research should then adhere to greater methodological rigor, in order to investigate the significance of radiographies as a screening test.

Clinical practice: an approach to stridor in infants and children

Stridor is the sound caused by abnormal air passage during breathing. The cause of stridor can be located anywhere in extrathoracic airway (nose, pharynx, larynx, and trachea) or the intrathoracic airway (tracheobronchial tree). Stridor may be acute (caused by inflammation/infection or foreign body inhalation) or chronic. It may be congenital or acquired. Stridor is a sign from which the underlying cause must be sought; it is not a diagnosis. The role of the pediatrician faced with a child or infant with noisy breathing is: (1) to determine the severity or respiratory compromise and the need for immediate intervention (to prevent respiratory failure); (2) to decide based upon history and clinical examination whether a significant lesion is suspected and, in the latter situation, to refer the child to an ENT surgeon for an upper and lower airway endoscopy; (3) to understand the consequences and management strategies of the underlying lesion and to collaborate with colleagues from related disciplines for follow-up and subsequent management of the child.