JMIR Publications

ABSTRACT

Background:

The upper airways are formed by the nasal cavities, pharynx, and larynx. There are several radiographic methods that allow to evaluate the craniofacial structure. The upper airway analysis in Cone-Beam Computed Tomography (CBCT) may be useful in assisting to diagnose some pathologies such as the Obstructive Sleep Apnea Syndrome (OSAS). OSAS prevalence has increased significantly in recent decades justified by increased obesity and average life expectancy. It can be associated with cardiovascular, respiratory and neurovascular diseases, diabetes and hypertension. In some individuals with OSAS the upper airway is compromised and narrowed. Nowadays, CBCT is widely used in dentistry by clinicians. Its use for upper airways assessment would be an advantage for screening some abnormalities related to an increased risk of pathologies like OSAS. CBCT allows calculating the total volume of the airways, as well as its area in the different anatomical planes (sagittal, coronal and transverse). It also allows the identification of the regions with the highest anteroposterior and laterolateral constriction of the airways. Despite the undoubted advantages of airway assessment, in dentistry it is not routinely done. There is no protocol that allows comparisons between studies, which makes difficult to obtain scientific evidence in this area. So, there is an urgent need to standardize the protocol for the upper airways measurement to help clinicians to identify at-risk patients.

Objective:

The main aim is to create a standard protocol for upper airways evaluation in CBCT for OSAS screening in dentistry.

Methods:

To measure and evaluate the upper airways the data is obtained through Planmeca® ProMax 3D (Planmeca, Helsinki, Finland). The patient orientation is performed according to the manufacturer's indications at the time of image acquisition. The exposure corresponds to 90 kV, 8 mA and 13,713 s. The software used for upper airway analysis is Romexis® version 5.1.O.R (Planmeca, Helsinki, Finland). The images are exhibited according to the field of view of 20.1 x 17.4 cm, size 502 x 502 x 436 mm and the voxel of 400 μm.

Results:

The described and illustrated protocol presented in this article allows to automatically calculate the total volume of the pharyngeal airspace, its area of greatest narrowing, its location and the smallest anteroposterior and laterolateral dimensions of the pharynx. These measurements are done automatically by the imaging software whose reliability is proven by the existing literature. In this way we reduce the possible bias of manual measurement, aiming at data collection.

Conclusions:

The use of this protocol by dentists will allow to standardize the measurements and constitutes a valuable screening tool for OSAS. This protocol may also be suitable for other imaging software. The most relevant for standardizing the studies in this field are the anatomical points used as reference.