ABSTRACT
Abstract
Objective:
To describe the external and
middle ear of
goats, using computed
tomography and endoscopic
dissection, comparing them with the
anatomy of the
human ear, aiming to evaluate the viability of this
animal model for
training in otological endoscopic
surgery.
Methods:
Images of the external and
middle ear of
goats were produced by computed
tomography in the coronal and axial planes and analyzed. The radiological
anatomy of the external and middle
goat and
human ear are described. Some
measures of surgical interest were described, such as the length of the
external auditory canal, external and internal cross-sectional area of the
external auditory canal,
middle ear depth, vertical angle of the
external auditory canal, length of
malleus and
incus. After the tomographic study, we analyzed the importance of evaluations through the endoscopic
dissection of the
goat ear.
Results:
The bony canal is extremely tortuous and shows a bony prominence with significant elevation near the lower edge of the
tympanic membrane. The
middle ear has a large tympanic
bulla in the hypotympanum region. The
malleus is shaped similarly to that of the
human, but its handle is located anterior to its
head. The
mastoid is not pneumatized. Compared to the
human mastoid, there was a statistically significant difference in the external and internal cross-sectional area, at the depth of the
middle ear, in the vertical angle of the canal and in the length of the
incus.
Conclusion:
Goat morphometric
anatomy showed that this model is suitable for surgical simulation in the initial
training for endoscopic otological
surgery. It is an important contribution to the development of skills to accelerate the subsequent endoscopic otological surgical
training in
humans, despite some differences found.