Measurement of Angle and Length of the Eustachian Tube on Computed Tomography Using the Multiplanar Reconstruction Technique

Abstract

Objective: To obtain clues on the anatomical features of the eustachian tube (ET) related to the susceptibility to otitis media with effusion (OME) in children. Methods:The angle and length of the ET in children with (54 ears, OME children) and without OME (50 ears, normal children), as well as those of normal adults were measured on the CT using the multiplanar reconstruction technique Results:The angles of ET in OME children group, normal children group, and normal adult group were 20.4±3.5 degree (°) and 21.2±4.8°, 19.9±3.4°and 20.0±3.6°, and 27.3±2.7° and 27.3±2.8° in the right and left sides, respectively. There was no significant difference between the right and left sides in any group (p=0.541, p=0.952, p=0.978). The lengths of the ET in the OME children group, normal children group, and normal adult group were 37.2±3.0 mm (mean±standard deviation) and 37.6±3.2 mm, 37.5±3.3 mm and 38.0±3.2 mm, and 42.5±2.8 mm and 42.9±2.9 mm in the right and the left side, respectively. There was no significant difference between in the right and left sides in any groups (p=0.670, p=0.597, and p=0.545).Both the angles and lengths were significantly greater in the normal adult group than in either the OME children group or normal children group (one-way ANOVA and Fisher's PLSD tests, p<0.05), but there was no significant difference either in the angle or length of the ET between the OME group and normal children group (p>0.05). In the OME and normal children groups, the angle was observed to constantly increase with age, and the values were found to be within the range of the adult size in all the cases older than 2737 days and 2818 days in the OME children group and in normal children group, respectively. In addition to the angle, the lengths were observed to constantly increase with age, but the increase appeared to be greater in younger age until around 1000 to 1500 days (3 to 4 year old) than in the older age, and the values were found to be within the range of the adult size in all the cases older than 2470 days and 2818 days in OME children group and in normal children group, respectively. Conclusion:The angle and length of ET are more horizontal and shorter in infants than in adults. However, there is no statistical difference between the angle and length of ET in infants with and without OME. These results suggest that short and horizontal ET may be one of the predisposing factors related to the high susceptibility of OME in infants and children rather than etiological factors.

Trompa patulosa

“…Algunos estudios con tomografía computada han mostrado que el examen endoscópico nasal es mejor en alcanzar aquellas áreas difíciles de visualizar en la tomografía computarizada 25,26 . Es por esto, que actualmente se consideran procedimientos complementarios.…”

A case with posterior fossa epidermoid cyst showing audiovestibular symptoms caused by insufficiency of anterior inferior cerebellar artery – usefulness of free DICOM image viewing and processing software

“…Recently, as digital imaging and communications in medicine (DICOM) of computed tomography (CT) and MRI, and viewing and processing software have advanced (6), it has become possible to observe and measure structures seen in the CT and MRI three-dimensionally in a way that meets our needs (7,8).…”

The Diffrentiation of the Angles of Eustachian Tubes In the Patient Chronic Suppurative Otitis Media With and without Cholesteatoma

“…The angle of the Eustachian tube will be measured using multiplanar reconstruction techniques. Angle of the ET was defined as the angle of a straight line from the pharyngeal orifice to the tympanic orifice of the ET against Reid's standard plane, which is difined as the plane connecting the infraorbita margins with the upper margins of the external auditory meatus (Takasaki, 2007). The subjects of the study were 54 people which consist of 27 people in the cholesteatoma group and 27 people in the group without cholesteatoma taken with consecutive sampling.…”

“…The multiplanar reconstruction technique (MPR) is one of several new imaging techniques in computed tomography (CT) that makes the anatomical features of the Eustachian tube more pronounced. By using multiplanar reconstruction techniques, the image can be adjusted as desired by changing the angle of the plane every 0.5 degrees and changing the station every 1 millimeter (Takasaki, 2007).…”

“…The angle of the Eustachian tube was measured using the program osirix lite application. As explained in the introduction, Angle of the ET was defined as the angle of a straight line from the pharyngeal orifice to the tympanic orifice of the ET against Reid's standard plane, which is difined as the plane connecting the infraorbita margins with the upper margins of the external auditory meatus (Takasaki, 2007). Distribution of data of the angle of Eustachian tube was analyzed using Shapirowilk test.…”