New method of using reconstructed images for assessment of patency of intracochlear spaces for cochlear implant candidates.
OBJECTIVE
A new method of reconstruction using multidetector-row helical computed tomography (MDCT) was applied for assessment of cochlear patency in cochlear implantation candidates.


METHODS
Descriptive study comparing radiologic and surgical findings in eight radiologically normal cochleas and four abnormal cases.


METHODS
In unusual cases including cochlear ossification and misinsertion of electrodes, intracochlear space was evaluated on two types of reconstructed images: the "basal turn plane" that was vertical to the modiolus and contained whole basal turn was effective in the assessment of the lining of the inner bony wall of the otic capsule; "cochlear cross plane" images allowed evaluation of the patency of the intracochlear space and the location of inserted electrodes at the sections vertical to the direction of insertion of the electrodes.


RESULTS
Preoperative evaluation was useful for predicting possible problems in electrode insertion and therefore helped in decision-making in regards to surgical strategies, especially in candidates with a high probability of cochlear ossification such as those with meningitis and otosclerosis. Furthermore, the new reconstruction method also provided useful information on the position of the cochlear implant electrodes after surgery.


CONCLUSIONS
These unusual cases demonstrated that preoperative MDCT evaluation by our reconstruction method was useful for predicting possible problems in electrode insertion and decision-making in regards to surgical strategies, especially in cochlear implantation candidates with a high probability of cochlear stenosis.
Karino
Shotaro
S
Department of Otolaryngology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
Hayashi
Naoto
N
Aoki
Shigeki
S
Ohtomo
Kuni
K
Yamasoba
Tatsuya
T
D000293:Adolescent; D003051:Cochlea / Q000000981:diagnostic imaging*; D003054:Cochlear Implants; D003638:Deafness / Q000209:etiology / Q000601:surgery; D004567:Electrodes, Implanted; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008581:Meningitis / Q000150:complications; D008875:Middle Aged; D010040:Otosclerosis / Q000000981:diagnostic imaging / Q000601:surgery; D014057:Tomography, X-Ray Computed