Experimental Flat-Panel High-Spatial-Resolution Volume CT of the Temporal Bone

Sections of the middle and inner ear (specimen 1) acquired by MSCT (A and C) and VCT (B and D). VCT data were reformatted to visually align the cut plane with the corresponding MSCT section. Owing to variable section thicknesses, perfect alignment was not possible. In the VCT dataset, more anatomic structures are visible and better delineated. Star indicates high jugular bulb; cross, carotid canal. See Table for numbered annotations.

Volume-rendered image of the ossicular chain obtained from specimen 1 by MSCT (A) and VCT (B). The ossicular chain is shown from an anterior viewpoint. A thin, longitudinal groove along the length of the posterior crus of stapes (arrow) is delineated by VCT but not MSCT. To visualize the gap in stapes, A had to be acquired from a steeper angle than that of B because of the higher section thickness employed by MSCT.

VCT reformations of specimen 1. A shows a reformation in the plane of the anterior and posterior crus of stapes and its footplate. B was acquired in a plane through the cochlea and IAC that clearly shows the modiolus; it also shows the bifurcation of cranial nerve VIII due to the air in the dissected specimen. The facial nerve and its canal are shown in the more horizontal section shown in C and more sagittal section shown in D. Part of the proximal vestibular aqueduct (26), a structure that can be traced throughout its length on these scans, is seen in C. Star indicates high jugular bulb; cross, tensor tympani muscle. See Table for numbered annotations.

Volume-rendered images of the ossicular chain obtained from specimen 2: MSCT (A) and VCT (B) datasets. The bigger lesion (large arrowheads) is seen on both scans, whereas the smaller lesion (small arrowhead) is appreciated on only the VCT scan. The lesion in the neck of malleus resulted in slight subluxation of the handle of malleus.

Reformations of MSCT (A) and VCT (B) datasets obtained from specimen 3 showing the cochlear implant. On the VCT image, contamination from the metal artifacts is considerably less than that on the MSCT image; the cochlea and individual electrodes of the implant can be clearly assessed. See Table for numbered annotations.

Reformations of MSCT (A) and VCT (B) datasets obtained from specimen 4 showing the fixation of the middle-ear FMT hearing aid on the long process of incus. Metal artifacts of the iron coil render an assessment of adjacent structures impossible on the MSCT image. On the VCT image, the artifacts are reduced to clearly show the handles of the clamp around the long process of incus (arrows). See Table for numbered annotations.