The variation of superior semicircular canal bone thickness in relation to age and gender

Comparison of Superior Semicircular Canal Bone Thickness and Patterns in Unilateral and Bilateral Cleft Patients and Normal Controls: A CBCT Study

Superior Semicircular Canal Dehiscence (SSCD) is a recently-defined developmental defect may be associated with several craniofacial anomalies such as Cleft Lip/Palate (CLP). The present study aimed to compare subjects with unilateral and bilateral CLP and normal controls in terms of Superior Semicircular Canal (SSC) bone thickness and pattern.

A total of 238 Cone Beam Computed Tomography (CBCT) images were collected from 52 unilateral Cleft Lip and Palate (UCLP) subjects (104 temporal bones) and 38 Bilateral Cleft Lip and Palate (BCLP) (76 temporal bones) subjects and 148 healthy controls (296 temporal bones). The SSC bone thickness was measured twice and validated by a maxillofacial radiologist. The samples were then classified into five categories based on bone thickness: papyraceous or thin, normal, thick, pneumatized, and dehiscence. After all, the UCLP, BCLP, and normal control groups were compared concerning the SSC pattern and thickness.

The results revealed no significant difference among the three groups regarding the SSC pattern and thickness based on gender. The SSC patterns (P value = .001) and SSC thickness (0.01) were strongly correlated to the cleft type. The thinnest bone thickness and the highest incidence of SSCD were observed among the subjects with BCLP.

The results showed a significant association between the SSC patterns and SSC thickness and the study groups.

The evaluation of superior semicircular canal in patients with unilateral cleft lip and palate using CBCT

OBJECTIVES

The present study aims to evaluate the thickness and radiological patterns of the superior semicircular canal (SSC) in patients with unilateral cleft lip and palate (CL/P).

METHODS

Cone beam computed tomography (CBCT) images of the patients were evaluated in axial and Pöschl planes. CBCT images of 84 patients with unilateral CL/P and 168 healthy individual controls were included in the study. Three study groups were established: the CS-CL/P group (cleft side temporal bones of the CL/P patients), NCS-CL/P (non-cleft side temporal bones of the CL/P patients) and the control group. The radiological patterns of SSCs were categorized as dehiscence, papyraceous, normal, pneumatised and thick. The minimum bone thickness of SSC was measured.

RESULTS

It was found that the CS-CL/P group had a higher prevalence for SSCD compared to both the NCS-CL/P group and the control group. CS-CL/P group had a higher prevalence of dehiscence type and papyraceous type compared to the control group. The SSC thickness on the CS-CL/P patients was thinner than the NCS-CL/P patients and the control group sides (p = 0.033 and p < 0.001, respectively).

CONCLUSIONS

The mean thickness of SSC was found significantly lower in the CS-CL/P group compared to both the NCS-CL/P group and the control group. The elevated prevalence of dehiscence and papyraceous types in the CS-C/LP group compared to the control group implies that the presence of a cleft may be a predisposing factor for these types.

Superior semicircular canal dehiscence: a radiological and clinical study

Aim

to assess radiologically the prevalence of SSCD with its clinical presentations and its relationship with age.

Methods

a prospective cohort study carried out on 200 consecutive patients (400 temporal bones). Radiological evaluation was performed using High Resolution Computed Tomography (HRCT) with measurement of thickness of bone covering superior semicircular canal (SCC), height and diameter of SSC.

Results

Two hundred patients (400 temporal bones) were involved. The mean thickness ± SD, the mean diameter ± SD and the mean height ± SD were 1.38 ± 0.80 mm, 0.94 ± 0.26 mm and 10.91 ± 2.39 mm respectively. The prevalence of SSCD and predehiscence were 1% and 14% respectively. The commonest symptom encountered was autophony (48.3%). When the SSC thickness, diameter and height were compared with the age of patients, statistically significant differences were detected. The highest diameter, lowest height and lowest thickness were found in patients aged from 54 to 72 years. Thickness of bony layer covering SSC was found to be the most validated measurement for differentiation between cases with positive and negative symptoms with the highest sensitivity and specificity.

Conclusion

The prevalence of SSCD and predehiscence varied among the studies. Autophony is the commonest symptom usually encountered. The condition is acquired rather than congenital. The thickness of bone covering SCC is the most validated measurement in differentiation between cases with positive and negative symptoms.

Evaluation of Superior Semicircular Canal Morphology and Its Relationship with Glenoid Fossa Roof Thickness Using Cone Beam Computed Tomography

Purpose

This study aimed to evaluate the bone thickness of the superior semicircular canal (SSC) roof and its relationship with the roof thickness of the glenoid fossa (RGF).

Methods

The cone beam computed tomography (CBCT) images of 280 patients (560 temporal regions) were surveyed. The lowest thickness of the SSC roof was measured and categorized based on the radiological patterns of the Cisneros et al. classification. The thickness of GF and the presence of dehiscence in this part were determined, as well. The relationship between the thickness of the GF roof and the bone thickness covering the SSC was also assessed.

Results

The mean thickness of the SSC roof was 0.93 ± 0.48 mm, with no significant difference among different age groups and genders (p > 0.05). However, superior semicircular canal dehiscence (SSCD) was more prevalent among females over 45 years old. Similarly, the individuals with the dehiscence of the GF roof had a 12.93-fold higher chance of SSCD development.

Conclusions

The results indicated that the thickness of the bone overlying the SSC was significantly related to the roof thickness of the GF. However, an increase in age resulted in no significant change in the bone thickness of the SSC roof. Gender also had no role in changing the thickness of the bone overlying the SSC. Considering the decrease in the thickness of the SSC roof among females over 45 years of age, menopause may be responsible for this occurrence as well as for the increase in the prevalence of SSCD.

Dehiscence or thinning of bone overlying the superior semicircular canal in idiopathic intracranial hypertension

STUDY DESIGN

Retrospective cohort.

OBJECTIVES

The objective of the study is to evaluate a relationship between idiopathic intracranial hypertension (IIH) and superior semicircular canal dehiscence (SSCD) of bone overlying the superior semicircular canal (SSC).

MATERIALS AND METHODS

A total of 57 (114 ears) individuals, 20 of whom were controls and 37 of whom were IIH, were included in the study. Individuals were evaluated with 0.8 mm slice thickness computed tomography (CT) images for SSC bony roof thickness and SSCD. Thickness of the bony roof over the SSC was graded from Grade 1 to Grade 4. Grade 3 was defined as pre-dehiscence and Grade 4 as dehiscence.

RESULTS

Bony roof thickness was 1.25 mm in the control group and 0.76 mm in the IIH group. When bony roof thickness was compared between the groups, it was found to be significantly thinner in the IIH group (p = 0.012). In the IIH group, while dehiscence was detected in 25 of 74 ears, no dehiscence was detected in 49 ears. In the control group, while dehiscence was detected in 5 ears, no dehiscence was detected in 35 ears. The difference is statistically significant (p = 0.015). The correlation between bony roof thickness and cerebrospinal fluid (CSF) pressure in the IIH group was not statistically significant (p = 0.343; rho = 0.110). The correlation between bony roof thickness and age in the IIH group was not statistically significant (p = 0.082; rho =  - 0.164).

CONCLUSION

Increased CSF pressure in patients with IIH may cause chronic, progressive, and irreversible damage to the bone of the SSC and, according to our study, the rate of SSCD was found to be high in IIH patients.

The evaluation of superior semicircular canal bone thickness and radiological patterns in relation to age and gender

PURPOSE

The present study aims to evaluate the superior semicircular canal (SSC) bone thickness and radiological patterns in relation to age and gender in a Turkish population using cone beam computed tomography (CBCT).

METHODS

A total of 450 temporal bones were evaluated in the study by two examiners. The radiological patterns of SSC were categorized as follows: dehiscent, papyraceous, normal, thick and pneumatised patterns. The bone thickness of SSCs were measured.

RESULTS

The mean bone thickness of the SSC for females was 1.079 ± 0.8 mm. For males, the mean bone thickness was 0.952 ± 0.6 mm. There was no significant difference between males and females for the mean bone thickness of the SSC. (p > 0.05) The normal pattern was found in 258 temporal bones (57.3%). Seventy-two cases (16%) were defined as "papyraceous pattern"; 23 cases (5.1%) were defined as "thick pattern" and 42 cases (9.3%) were defined as "pneumatised pattern". SSC dehiscence was determined in 55 cases (12.2%). There was no significant difference between radiological patterns for age groups and gender (p > 0.05).

CONCLUSION

There was no significant relationship between SSC bone thickness with age and gender. The radiological patterns of SSC were not associated with age and gender. Radiologists evaluating the head and neck region for various reasons should be aware of these structures and report not only the SSC dehiscence but also the papyraceous pattern.