Siegfried A. Schwab, Presenter: Nothing to Disclose

Sebastian Eberle, Abstract Co-Author: Nothing to Disclose

Johannes Zenk MD, Abstract Co-Author: Nothing to Disclose

Michael Marcus Lell MD, Abstract Co-Author: Nothing to Disclose

Michael Uder MD, Abstract Co-Author: Speakers Bureau, Bracco Group Speakers Bureau, Bayer AG Research Consultant, Insight Agents GmbH Research Consultant, General Electric Company Research grant, Siemens AG Research grant, Koninklijke Philips Electronics NV

The aim of this study was to evaluate a 128-slice single shot technique (SST) for the CT imaging of the temporal bone in comparison to conventional spiral Multislice Computed Tomography (MSCT) by means of image quality, examination time and radiation exposure.

54 temporal bones of 27 patients were scanned with both a conventional MSCT and 128-slice SST. After blinding and randomization of both examinations two observers assessed the visualisation of thirty-eight anatomical structures using a constant slice thickness of 0.8mm. The differences in evaluation scores obtained for the two techniques were analyzed using a Wilcoxon signed-rank test whereas a p value of less than 0.05 was considered significant. For both methods imaging time and radiation exposure (dose length product) was noted.

Altough MSCT subjectively resultet in sharper images of the temporal bone, the visualisation of the whole evaluated anatomical structures together did not differ significantly between the two techniques (p>0,05) Comparing the anatomical structures separately there was a better visualisation of the lateral malleal ligament with MSCT whereas the cochlear septa were ranked higher with SST (p<0,05). Imaging time and mean dose length product for MSCT were 12.3s and 50,3 mGy; for SST it was 1s and 16,8 mGy (dose reduction of 66%).

128-slice SST can be used for the imaging of the temporal bone with a comparable diagnostic accuracy to MSCT, altough overall subjective image quality is inferior with SST.

The main advantages of SST compared to MSCT are a dramatic reduction of imaging time and radiation exposure, which is of special importance in uncooperative patients or children.

Schwab, S, Eberle, S, Zenk, J, Lell, M, Uder, M, Does 128 Slice Single-shot MSCT Have the Potential to Become an Alternative to Conventional Spiral MSCT for Imaging of the Temporal Bone?.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9000343.html