Use of reconstructed sagittal computed tomography images to plan middle cranial fossa surgery

To facilitate planning in temporal bone surgery for the middle cranial fossa approach by using sagittal reconstructed temporal bone computed tomography images.

Comparison of anatomic measurements on random high-resolution, reformatted computed tomography scans of the temporal bone.

High-resolution computed tomography of 10 normal temporal bones in the axial and coronal planes was obtained, and two-dimensional sagittal reconstructions were performed using a commercial software program. Eight anatomical relationships between neural and/or vascular structures were measured. Representative images were inverted to recreate the plane of the middle cranial fossa approach.

Anatomical relationships among the vestibule, superior semicircular canal, internal auditory canal, internal carotid artery, and middle cranial fossa exhibited a high SD in the 10 subjects. The sample size and the large range for the eight anatomical relationships precluded the detection of a significant difference between right and left temporal bones or sex and age of the patient.

The present report presents a novel, practical measurement protocol for rapidly evaluating important individual anatomical differences in patients before middle cranial fossa surgery. Inverted sagittal reconstructions facilitate presurgical planning for the middle cranial fossa approach by 1) assessing critical anatomical relationships before surgery and 2) providing customized measurements between vital landmarks and the first in vivo measurements. This decreases the likelihood of surgical mishaps and improves teaching by providing the first in vivo measurements of practical anatomical relationships in the sagittal plane.