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Radiological patterns of the posterior semicircular canal
Ana Isabel Cisneros1, Jaime Whyte, Claudio Martínez
1Department of Human Anatomy and Histology, School of Medicine, University of Zaragoza, C/Domingo Miral, s/n, 50009, Zaragoza, Spain, aicisner@unizar.es.
Surgical and Radiologic Anatomy : SRA
|June 21, 2013
Summary
Radiologists identified five posterior semicircular canal (PSC) patterns using CT scans. Thin or dehiscent PSC bone can lead to pathology.
Area of Science:
- Radiology
- Anatomy
- Otolaryngology
Background:
- The posterior semicircular canal (PSC) is a crucial component of the inner ear.
- Understanding its anatomical variations is essential for diagnosing inner ear pathologies.
Purpose of the Study:
- To identify and define the radiological patterns of the posterior semicircular canal (PSC).
- To provide readily applicable conclusions for clinical practice.
Main Methods:
- Multi-slice helical computed tomography (CT) was used to analyze the parietal morphology of the PSC.
- Standardized measurements of normality were used as a reference to classify bone cover types.
Main Results:
- Five distinct radiological patterns of the PSC were identified in 318 patients (604 petrous bones): normal, thick, thin, pneumatized, and dehiscent.
- The normal pattern (0.9-2.5 mm thickness) was most common (54.13%), followed by thin (≤1.2 mm, 26.15%), and thick (≥2.6 mm, 16.39%).
- Pneumatized and dehiscent patterns were less common, occurring in 3.14% and 0.3% of cases, respectively.
Conclusions:
- Five radiological patterns of the PSC (normal, thick, thin, pneumatized, dehiscent) were defined.
- The thin (<0.5 mm) and dehiscent PSC patterns are associated with potential pathology.
- Dehiscence may sometimes result from a thin bone cover.
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