Accuracy of image-guided surgical systems at the lateral skull base as clinically assessed using bone-anchored hearing aid posts as surgical targets.
OBJECTIVE
Image-guided surgical (IGS) technology has been clinically available for more than a decade. To date, no acceptable standard exists for reporting the accuracy of IGS systems, especially for lateral skull base applications. We present a validation method that uses the post from bone-anchored hearing aid (BAHA) patients as a target. We then compare the accuracy of 2 IGS systems-one using laser skin-surface scanning (LSSS) and another using a noninvasive fiducial frame (FF) attached to patient via dental bite-block (DBB) for registration.


METHODS
Prospective.


METHODS
Tertiary referral center.


METHODS
Six BAHA patients who had adequate dentition for creation of a DBB.


METHODS
For each patient, a dental impression was obtained, and a customized DBB was made to hold an FF. Temporal bone computed tomographic (CT) scans were obtained with the patient wearing the DBB, FF, and a customized marker on the BAHA post. In a mock operating room, CT scans were registered to operative anatomy using 2 methods: 1) LSSS and 2) FF.


METHODS
For each patient and each system, the position of the BAHA marker in the CT scan and in the mock operating room (using optical measurement technology) was compared, and the distances between them are reported to demonstrate accuracy.


RESULTS
Accuracy (mean +/- standard deviation) was 1.54 +/- 0.63 mm for DBB registration and 3.21 +/- 1.02 mm for LSSS registration.


CONCLUSIONS
An IGS system using FF registration is more accurate than one using LSSS (p = 0.03, 2-sided Student's t test). BAHA patients provide a unique patient population upon which IGS systems may be validated.
Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Vanderbilt University, Nashville, Tennessee, USA.
Ramya
R
Balachandran
J Michael
JM
Fitzpatrick
Robert F
RF
Labadie
D038263:Auditory Brain Stem Implantation / Q000379:methods*; D038262:Auditory Brain Stem Implants; D004867:Equipment Design; D006310:Hearing Aids; D006801:Humans; D007091:Image Processing, Computer-Assisted; D013506:Otologic Surgical Procedures / Q000295:instrumentation / Q000379:methods; D012680:Sensitivity and Specificity; D019291:Skull Base / Q000000981:diagnostic imaging* / Q000601:surgery; D025321:Surgery, Computer-Assisted; D013701:Temporal Bone / Q000000981:diagnostic imaging / Q000601:surgery; D014057:Tomography, X-Ray Computed