Clinically significant abnormal findings on the "nondiagnostic" CT portion of low-amperage-CT attenuation-corrected myocardial perfusion SPECT/CT studies.
Attenuation correction is recommended to optimize the performance of cardiac SPECT. The 2.5-mA CT commonly used for this purpose in myocardial perfusion SPECT is generally considered "nondiagnostic" in quality. In other areas of cardiac and hybrid imaging, diagnostically relevant abnormal findings on higher-quality CT studies have been described. The purpose of this study was to establish the frequency and significance of abnormal findings on low-amperage-CT cardiac SPECT/CT scans and to assess whether a systematic review of the nondiagnostic CT findings should be recommended.


METHODS
Two hundred consecutive patients who underwent clinical low-amperage-CT attenuation-corrected myocardial perfusion studies acquired on a SPECT/CT system were included in the study. The cardiac CT images were reviewed in consensus by both an experienced CT reader and a nuclear medicine resident less experienced in CT. Abnormal CT findings of varying significance were recorded.


RESULTS
Eighty-one patients had no abnormal CT findings. In the remaining 119 patients, 234 abnormalities were detected. Twenty-five major findings (in 21 patients) were seen, and 16 of these had been previously unrecognized. Sixty-four minor and 131 minimal findings were noted. Fourteen findings were labeled as equivocal (i.e., the CT findings were not definite).


CONCLUSIONS
Potentially significant abnormal findings on the nondiagnostic-CT portion of the cardiac SPECT/CT examination were detected in 10.5% of our patients. These data suggest that, in addition to the review of the emission image dataset, low-amperage-CT findings should routinely be assessed for major diagnostic abnormalities.
Goetze
Sibyll
S
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA.
Pannu
Harpreet K
HK
Wahl
Richard L
RL
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000473:pathology; D010477:Perfusion; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
D019275:Radiopharmaceuticals