Introduction:
Since about 30 years cochlear implants (CI) have been evolved to a standard procedure
for auditory rehabilitation of deaf patients. The optimal position of the CI electrode
is essential for a good surgical result. For postoperative position control are conventional
x-ray diagnostics, computed tomography (CT) or digital volume tomography (DVT) available.
A new method is Dyna-CT which uses a high resolution CT on flat detector angiography
equipment. During the procedure the tube turns several times around the head of the
patient. High resolution pictures for high contrast structures can be reconstructed
out of the recovered data.
Methods:
In the last two years 59 patients obtained a position control after CI surgery with
Dyna-CT.
Results:
The postoperative position control with Dyna-CT showed always a high picture quality
and allowed a 3D illustration without further technology. With this procedure we could
identify as well the depth as the correct localization of the electrode in the scala
tympani. The average radiation exposure was about 50% less than with conventional
CT.
Conclusion:
With the use of Dyna-CT we can achieve a reliable position control and determine the
penetration depth of the CI with a comparatively low radiation exposure.
