[18F-fluorodeoxyglucose PET/CT in the diagnosis of vascular graft infection]. / Vozmozhnosti PET/KT S 18F-ftordezoksiglyukozoi v diagnostike infektsii sosudistykh protezov.

OBJECTIVE: To investigate diagnostic role of 18F-fluorodeoxyglucose PET/CT in patients with suspected vascular graft (VG) infection. MATERIAL AND METHODS: A prospective analysis included data of 30 PET/CT examinations for suspected infection of aortic VG (n=27) and bypass grafts (n=3) after surgical treatment (median 48 months). In 77% (23/30) of cases, the diagnosis was initially «possible¼ (n=11) or «rejected¼ (n=12) in accordance with common diagnostic criteria. All PET/CT results were verified by clinical, laboratory and intraoperative («=20) data. VG infection was confirmed in 18 patients and ruled out in 12 cases. RESULTS: PET/CT confirmed VG infection in 94% (17/18) and excluded in 50% (6/12) of cases. False PET/CT results were obtained in 23% (7/30) cases: false positive in 6 cases and false negative in 1 case. Thus, sensitivity, specificity and diagnostic accuracy of PET/CT were 94%, 50% and 77%, respectively; positive and negative predictive value - 74% and 86%. PET/CT results allowed correct reclassifying 33% (10/30) of cases. VG infection was confirmed in 73% (8/11) of patients with initially «possible¼ diagnosis and excluded in 17% (2/12) of patients with initially «rejected¼ infection. Moreover, whole body PET/CT revealed unknown inflammation foci outside VG in 73% (22/30) of cases. These data were applied to correct treatment approach in 80% (24/30) of cases. CONCLUSION: Our results showed high efficacy of 18F-fluorodeoxyglucose PET/CT in the diagnosis of VG infection. Despite low specificity, this technique has high sensitivity and accuracy that allowed reclassifying 33% of cases.

[ECG-gated single-photon emission computed tomography with 99mTC-tetraphosmin in diagnostics of short-term myocardium stunning under the condition of stress-induced ischemia in CHD patients with multivascular lesions of coronary vessels].

The authors analyzed the efficiency of ECG-gated single-photon emission computed tomography (SPECT) with 99mTc-tetraphosmin in diagnostics of short-term myocardium stunning in CAD patients with transient ischemia. The technique was applied to 16 CAD patients. Combined evaluation of perfusion was based on the analysis of radiotracer uptake level in left ventricle (LV) myocardium. In order to evaluate myocardium function the authors measured LV systolic thickening index, using 20-segment pattern. 8 out of 16 patients (50%) displayed the phenomenon of stress-induced stunning. The volume of stunned myocardium in individual patients was 2 to 7 LV segments. In general, up to 37% (29/78) of reversible perfusion defects are subjected to short-term stunning under the condition of transient ischemia. After surgical treatment, 84% of segments with signs of stunning normalized their functioning both under stress and at rest.