Radiological malformations of the ear in Pendred syndrome
P D Phelps1, R A Coffey, R C Trembath
1Royal National Throat Nose and Ear Hospital, London, UK.
Clinical Radiology
|May 19, 1998
Summary
Pendred syndrome, a common cause of syndromic hearing loss, often presents with inner ear malformations. High-resolution MRI is the preferred imaging method for diagnosing this condition.
Area of Science:
- Genetics
- Radiology
- Otolaryngology
Background:
- Pendred syndrome is the most frequent syndromic hearing loss, characterized by sensorineural deafness and thyroid issues.
- The genetic cause remains unidentified, and radiological features are poorly documented due to diagnostic challenges.
- This study investigates the radiological characteristics of Pendred syndrome in a cohort of 40 patients.
Purpose of the Study:
- To detail the prevalence of specific inner ear malformations in Pendred syndrome.
- To compare the diagnostic utility of computed tomography (CT) and magnetic resonance imaging (MRI).
- To establish the optimal imaging modality for investigating Pendred syndrome.
Main Methods:
- Analysis of radiological data from 40 patients meeting strict diagnostic criteria for Pendred syndrome.
- Evaluation of inner ear malformations, including Mondini deformity, using CT and MRI.
- Detailed comparison of CT and MRI findings, focusing on high-resolution MRI with T2 protocol.
Main Results:
- Mondini deformity (cochlear interscalar septum deficiency) is common but not universal in Pendred syndrome.
- All 20 patients evaluated with MRI showed endolymphatic sac/duct enlargement and a large vestibular aqueduct.
- High-resolution MRI demonstrated superior detail compared to CT for inner ear anomalies.
Conclusions:
- Enlargement of the endolymphatic sac and duct with a large vestibular aqueduct are consistent findings in Pendred syndrome.
- Thin-section, high-resolution MRI in axial and sagittal planes with a T2 protocol is the imaging method of choice.
- Further research into the genetic basis of Pendred syndrome is warranted.
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