Christian Thilo MD, Presenter: Nothing to Disclose

U. Joseph Schoepf MD, Abstract Co-Author: Speakers Bureau, Bracco Group Speakers Bureau, General Electric Company Speakers Bureau, Bayer AG (MedRad, Inc) Speakers Bureau, TeraRecon, Inc Medical Advisory Board, Bracco Group Medical Advisory Board, General Electric Company Medical Advisory Board, Bayer AG Research grant, Bayer AG Research grant, Bracco Group Research grant, General Electric Company Research grant, Bayer AG (MedRad, Inc) Research grant, Siemens AG

Leonie Gordon MD, Abstract Co-Author: Speakers Bureau, Cytogen Corporation

Salvatore Chiaramida MD, Abstract Co-Author: Nothing to Disclose

Jill Serguson RT, Abstract Co-Author: Nothing to Disclose

Philip Costello MD, Abstract Co-Author: Consultant, Bracco Group Research grant, Siemens AG

Adrian T. Parker BA, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

To evaluate a prototype mobile SPECT unit integrated with a 64-slice cardiac CT scanner for obtaining complementary information on coronary anatomy and pathophysiologic lesion severity in patients with low to intermediate likelihood of significant coronary artery disease (CAD).

25 consecutive patients (mean age 60 yrs, 11 female) with suspected CAD underwent routine rest/stress SPECT myocardial perfusion imaging (MPI) with 10/30 mCi Tc-Sestamibi. Immediately afterwards, all patients underwent repeat MPI with a mobile SPECT scanner (Jupiter, Siemens) which can be attached to a 64-slice multi detector-row CT unit when needed. A non-contrast CT calcium scoring scan was used for attenuation correction. Contrast enhanced 64-slice CT coronary angiography (cCTA) was performed without re-positioning the patient. Jupiter-MPI was compared with routine MPI for detection of myocardial perfusion defects (PD). Two experienced observers diagnosed presence or absence of CAD based on MPI alone, cCTA alone, and based on combined MPI and cCTA with fused image display of both modalities.

23/25 patients were successfully imaged with all modalities (1 poor quality cCTA due to tachyarrhythmia, 1 MPI prematurely aborted by patient). In 22/24 patients Jupiter MPI corresponded with diagnosis at routine MPI (r=0.80). Stenosis >50% at cCTA was detected in 6/24 patients. 6/24 patients had PD at MPI. 3 of these had normal coronary arteries at cCTA. 3 patients with ≤50% stenosis at cCTA had PD at MPI. 3/18 patients with normal MPI studies had significant stenosis at cCTA, subsequently confirmed at cardiac catheterization. Significant incidental extracardiac findings were detected in 4 patients at cCTA.

A mobile SPECT unit integrated with a cardiac CT scanner has potential for identifying significant stenosis without PD, excluding significant stenosis in the presence of PD, and gauging hemodynamic significance of intermediate lesions detected at cCTA.

Noninvasive complementary evaluation of morphologic and functional CAD by integration of cardiac CT with a mobile SPECT unit is feasible and may improve the accuracy of CAD diagnosis.

Thilo, C, Schoepf, U, Gordon, L, Chiaramida, S, Serguson, J, Costello, P, Parker, A, et al, , et al, , A Mobile SPECT Scanner Combined with 64-Slice CT for Integrated Assessment of Coronary Anatomy and Perfusion: A Feasibility Study.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5005268.html