Age-related changes in the morphological relationship between the supratubal recess and the Eustachian tube

Age-related morphological change in bony segment and cartilage segment of Eustachian tube

Background

Eustachian tube dysfunction (ETD) is the predominant cause of otitis media with effusion in children and adults. Balloon dilatation of the Eustachian tube (BDET) provides a new method for restoring the ventilatory function of Eustachian tube (ET). However, the differences in age-related morphological changes in the dimensions and positions of ET in children and adults are unclear.

Purpose

This study aimed to examine age-related morphological changes in bony and cartilage segments of the ET in a three-dimensional space in normal population.

Methods

A total of 71 randomly selected computed tomography (CT) images of the temporal bones of 46 people were retrospectively studied in four age groups: A (0-3 years old); B (4-8 years old), C (9-18 years old), and D (19-65 years old). Space analytic geometry was assessed to calculate the dimensions and positions of ET.

Results

The bony segment of ET lengthened from infancy to adulthood with age in groups A, B and C (r = 0.562**/0.000). The cartilage segment of ET mostly extended with age from infancy to 8 years old in children (r = 0.633**/0.000), but with bending close to the sagittal plane and away from the horizontal plane with age in groups A, B and C (P < .05), and with a constant angle to the coronal plane among the four groups (P > .05).

Conclusion

The bony and cartilaginous segments of ET exhibit distinct morphological changes in space with age. The bony segment of ET extends in a constant position from infancy to adulthood. In contrast, the cartilaginous segment of the ET indicates multidimensional positional changes until adulthood, in addition to the elongation from infancy to children. This may provide an accurate morphological basis for comparing the differences in ETD pathogenesis and surgical treatment between children and adults.

Eustachian Tube: Computed Tomography Analysis

BACKGROUND

Eustachian tube has a major role in ventilation, drainage, and protection of the middle ear. High resolution computed tomography magnifies the role of preoperative imaging for detailed inner and middle ear anatomical information. The aim of this study was to find an applicable way by computed tomography imaging for assessment of Eustachian tube. The goal was to provide improved understanding of the Eustachian tube measurements and the relationship with middle ear in Egyptian population. Computed tomography measurements for Eustachian tube were done including; length of the bony and cartilaginous portions, Total length of Eustachian tube, as well as the width and height of the tympanic orifice of the Eustachian tube. Also, tubotympanic and Reid plane- Eustachian tube angles were measured.

RESULTS

Within 200 studied ears in 100 subjects, the mean total Eustachian tube length was 40.19 ± 3.05 mm, mean length of the bony Eustachian tube was 11.69 ± 1.8 mm with significant longer Eustachian tube on left side, The mean length of the cartilaginous Eustachian tube was 28.5 ± 2.95 mm with significantly longer cartilaginous and total length in male (P < 0.0001). The mean width and height of the tympanic orifice of the Eustachian tube was 5.4 ± 0.79 and 4.85 ± 0.75 mm, respectively. The mean tubotympanic angle of the Eustachian tube was 148.11 ± 2.82°. The mean Reid plane- Eustachian tube angle was 27.69 ± 2.08° with significantly wider angle in males (P < 0.022).

CONCLUSION

The Eustachian tube measurements can easily be obtained on computed tomography images, and are representative for the Eustachian tube anatomy. There is importance of extending computed tomography examinations beyond the middle ear cavity and the mastoids to the Eustachian tube in order to have more data on its condition and relations with different pathological conditions. Computed tomography provides improved understanding of the Eustachian tube measurements and relationship with middle ear structures.

Distribution of different morphological types of anterior epitympanic plate “cog” and Köerner’s septum in CT images of cholesteatomatous and non-cholesteatomatous CSOM: is it really significant?

Background

The anterior epitympanic plate (cog) and Köerner’s septum are gaining more importance since the introduction of transcanal mastoidectomy as these anatomical structures are serving landmarks for the attic. Moreover, different morphological types of cog and Köerner’s septum revealed embryological relation to the development of the isthmic membrane; the latter is linked to aeration of the attic and thus affects the pathological development of the cholesteatoma.

Results

A retrospective review of CT images of 86 patients proved by surgical biopsies revealed: 49 cholesteatomas and 37 non-cholesteatomatous CSOM. The type-I “cog” had a higher incidence (n = 40) and was statistically more prevalent in non-cholesteatomatous CSOM (n = 30, 81.1%). Type-II was the second commonest and was statistically more prevalent in cholesteatomatous CSOM (n = 22, 44.9%). Type-III was the third commonest, seen in (n = 18, 20.9%) and was statistically more prevalent in cholesteatomatous CSOM (n = 17, 34.7%). Köerner’s septum was more prevalent in non-cholesteatomatous CSOM (70.3%) with statistical significance (p value = 0.002).

Conclusions

The difference in the distribution of different morphological types of anterior epitympanic plate “cog,” as well as the difference in Köerner’s septum existence amongst cholesteatomatous and non-cholesteatomatous CSOM are suggested as risk factors for the development of cholesteatoma and may predict a cholesteatoma on CT images.

Balloon Eustachian Tuboplasty (BET) in Children: A Retrospective Multicenter Analysis

OBJECTIVE

Generation of pilot data for planning of prospective BET-studies for treatment of dilatory Eustachian tube (ET) dysfunction in children.

STUDY DESIGN

Retrospective multicenter analysis.

SETTING

Nine ENT departments at tertiary care teaching hospitals.

PATIENTS

4-12-year-old children with chronic otitis media with effusion (COME) for more than 3 months or more than 3 episodes of acute otitis media during the last year, having failed standard surgical therapy at least once.

INTERVENTION

BET with or without paracentesis, ventilation tube insertion, or tympanoplasty.

MAIN OUTCOME MEASURES

Tympanic membrane appearance, tympanometry, and hearing threshold.

RESULTS

Two hundred ninety-nine ETs of 167 children were treated. Mean age was 9.1 years (95% confidence interval [95% CI]: 8.7-9.4 yr). In 249 ears (83.3%), COME and/or retraction of the tympanic membrane were the indication for BET. Median hearing threshold was 20 dB HL (95% CI: 0-46 dB). One hundred fifty-five ears (51.8%, 95% CI: 46.1-57.4%) showed a tympanogram type B. Treatment consisted of BET without other interventions ("BET-only") in 70 children, 128 ears. Median length of follow-up for 158 (94.6%) children was 2.6 months (95% CI: 0.3-16.1 mo). After treatment, the tympanic membrane appeared normal in 196 ears (65.6%, 95% CI: 60.0-70.8%, p < 0.001). Median hearing threshold improved to 10 dB HL (95% CI: 0-45 dB, p < 0.001). Tympanograms shifted toward type A and C (type A: 39.1%, 95% CI: 33.7-44.7, p < 0.001). These improvements were also observed in subgroup analyses of "BET-only" treatment and the indication of "COME" respectively.

CONCLUSION

BET is improving a variety of dilatory ET dysfunction-related ear diseases in children. This study provides detailed data for design and planning of prospective studies on BET in children.

Supratubal recess and sinus tympani: CT analysis of middle ear hidden areas

Background

High-resolution computed tomography (HRCT) magnifies the role of preoperative imaging for detailed middle ear anatomy particularly its hidden area. The purpose of the current study was to assess the sinus tympani (ST) and supratubal recess (STR) by HRCT, to create CT classification of the STR depth, and to study the relationship between ST types and the new STR grades.

Results

In HRCT of non-pathological temporal bones of 100 subjects (200 ears), measurements of the STR and ST were calculated, registered, and analyzed. The depth of the STR was classified into grade 1 with depth less than 3 mm, grade 2 with depth ranged between 3 and 5 mm, and grade 3 with depth more than 5 mm. The mean STR length, width, and height were 4.17 ± 0.86, 3.55 ± 0.65, and 3.64 ± 0.7 mm, respectively, while the ST mean length and width of were 2.52 ± 0.5 and 1.82 ± 0.78 mm, respectively, without significant differences between either sexes or sided. The ST types were found to be type A in 56 ears (28%), type B in 142 ears (71%), and type C in 2 ears (1%). The STR grading was grade 1 in 12 ears (6%), grade 2 in 160 ears (80%), and grade 3 in 28 ears (14%) without significant relationship between ST types and STR grading (P = 0.3).

Conclusion

The current study provided reliable and applicable methods of CT assessment of STR and ST that can help to predict the degree of surgical visibility of the ST and STR during ear surgery.

Surgical Parameters for Minimally Invasive Trans-Eustachian Tube CSF Leak Repair: A Cadaveric Study and Literature Review

BACKGROUND

Cerebrospinal fluid rhinorrhea from a lateral skull base defect refractory to spontaneous healing and/or conservative management is most commonly managed via open surgery. Approach for repair is dictated by location of the defect, which may require surgical exploration. The final common pathway is the eustachian tube (ET). Endoscopic ET obliteration via endonasal and lateral approaches is under development. Whereas ET anatomy has been studied, surgical landmarks have not been previously described or quantified. We aimed to define surgical parameters of specific utility to endoscopic ET obliteration.

METHODS

A literature review was performed of known ET anatomic parameters. Next, using a combination of endoscopic and open techniques in cadavers, we cannulated the intact ET and dissected its posterior component to define the major curvature position of the ET, defined as the genu, and quantified the relative distances through the ET lumen. The genu was targeted as a major obstacle encountered when cannulating the ET from the nasopharynx.

RESULTS

Among 10 ETs, we found an average distance of 23 ± 5 mm from the nasopharynx to the ET genu, distance of 24 ± 3 mm from the genu to the anterior aspect of the tympanic membrane and total ET length of 47 ± 4 mm.

CONCLUSIONS

Although membranous and petrous components of the ET are important to its function, the genu may be a more useful surgical landmark. Basic surgical parameters for endoscopic ET obliteration are defined.