Abstract
The oval window region has recently been identified as a potential route for drug diffusion into the inner ear. Locally applied gadolinium and trimethylphenylam- monium (TMPA) have been shown to directly diffuse into the vestibule through the oval window region. Given the potential importance of the oval window region in the dif- fusion of substances into the inner ear, this work aimed to use micro-CT to obtain a data set of anatomical characteristics of the annular ligament of the stapes in the human temporal bone, a region thus far poorly studied. Twenty-one temporal bones were micro-dissected to preserve the otic capsule and allow perfusion of fixative stains into the inner ear. The specimens were scanned with micro-CT methods to provide 3D reconstructions and measurement. The 3D reconstruc- tions were able to demonstrate an undisturbed stapes foot- plate and annular ligament from which measurements could be taken. This study found a wide variance in the volumes and thicknesses of the stapedial ligaments. There was a positive correlation between the size of the stapes footplate and the annular ligament.