Is there any developmental relationship between mastoid pneumatization and adenoid tissue volume?

Effects of tympanic membrane perforation, middle ear cavity volume, and mastoid aeration on hearing impairment

AIMS

To investigate the effects of the location and size of tympanic membrane (TM) perforation and middle ear cavity volume on conductive hearing loss in patients with TM perforation.

METHODS

Data were collected via a retrospective medical chart review.

RESULTS

We enrolled 128 patients with a mean age of 45.6 ± 10.1 years. The mean perforation size was 21.2 ± 8.6% of the TM area, and the mean air-bone gap (ABG) was 20.2 ± 8.6 dB HL on pure tone audiometry. Patients were divided into two groups based on mean ABG. Patients with a large ABG had a significantly larger TM perforation area and smaller mastoid volume. The TM perforation was most commonly located in the central section. However, regression analyses showed that the proportion of the perforated TM area was the only independent predictor of a large ABG (odds ratio, 1.053; 95% confidence interval, 1.022-1.085; p = 0.001). When we analyzed the frequencies in which hearing loss occurred due to TM perforation, we confirmed that hearing loss occurred mainly in the low-frequency range.

CONCLUSION

In patients with TM perforation, conductive hearing loss occurs mainly at low frequencies and in proportion to the size of the TM perforation.

Impact of the Angles of the Septal Deviation on the Degree of the Mastoid Pneumatization

Introduction:

The aim was to explore the developmental relationships between the angles of septal deviations and the degree of the mastoid pneumatization.

Materials and Methods:

In total, 143 patients with a diagnosis of septal deviation who underwent septoplasty were included. The patients were divided into three groups in terms of the angles of the septal deviation. The angle of the septal deviations was defined as mild (<9 degrees), moderate (between 9 and 15 degrees) and severe (15 degrees and above). The degree of the mastoid pneumatization of each groups were compared.

Results:

In right-sided septal deviation subjects, the right mastoid air cell volumes of group mild, moderate and severe were 6,31±2,33 cm3, 5,20± 1,51 cm3, and 5,31±1,57 cm3, respectively. The mean right mastoid volumes of each groups did not differ in right-sided deviations subjects (P>0.05). The mean left mastoid volumes of each groups did not differ in right-sided deviations subjects (P>0.05). In right-sided septal deviation subjects, the mean volume of the right and left-sided mastoid air cells of each groups did not differ (P>0.05). In left-sided septal deviation subjects, the mean volume of the right and left-sided mastoid air cells of each groups did not differ (P>0.05).

Conclusions:

No developmental relationships between the angles of septal deviations and the degree of the mastoid pneumatization was observed in the study.

Three-dimensional morphometric analysis of paranasal sinuses and mastoid air cell system using computed tomography in pediatric population

OBJECTIVES

To evaluate the volumetric relationship between the mastoid air cell (MAC) and paranasal sinus (PNS) in the pediatric population using three-dimensional reconstruction and the analysis technique of CT.

STUDY DESIGN

Retrospective cross-sectional study was conducted at a university-based, secondary referral hospital.

METHODS

PNS CT imaging data of 62 children (40 boys and 22 girls; mean age=13.4 ± 4.0 years) was reconstructed to the three-dimensional model with the surface-rendering algorithm (lower threshold of -1024 HU and upper threshold of -318 HU), and subsequently measuring the volume of the three PNSs (frontal, maxillary and sphenoid) and MAC. Hierarchical linear regression analysis was used to control the effect of age.

RESULTS

Controlling the effect of age, no significant linear regression relationship was found between the volume of MAC and PNSs. It was observed that PNSs and MAC showed a significant linear relationship with age. The regression slopes of PNSs were larger than that of MAC, especially the growth of maxillary and sphenoid sinuses was faster and larger than that of the frontal sinus and MAC. As the coefficient of determination was extremely small, the aging process itself could not effectively explain the volume variation of PNSs and MAC.

CONCLUSION

No interaction was observed in the pneumatization of the three PNSs (frontal, maxillary, and sphenoid) and MAC. It was found that the growths of PNSs and MAC are influenced by age. Further, maxillary and sphenoid sinuses tend to grow faster and become larger than the frontal sinus and mastoid air cell system. Thus, it is verified that environmental factors could be involved in the postnatal pneumatization process of the PNSs and MAC, which might influence MAC to a greater extent than the PNSs.