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In this contribution, several opportunities and challenges for long axial field of view (LAFOV) PET are described. It is an anthology in which the main issues have been highlighted. A consolidated overview of the camera system implementation, business and financial plan, opportunities and challenges is provided. What the nuclear medicine and molecular imaging community can expect from these new PET/CT scanners is the delivery of more comprehensive information to the clinicians for advancing diagnosis, therapy evaluation and clinical research.

Objective Repeated left ventricular ejection fraction (LVEF) analyses with sequential single-dose radionuclide ventriculography might be an interesting technique for monitoring the effect of positive inotropic interventions. The aim of the study was to assess the reproducibility of LVEF measurement with planar radionuclide ventriculography within 3 h, using a standard single dose of radioactive tracer. Methods Sixteen patients underwent routine planar radionuclide ventriculography with a standard dose of 500 MBq of [[Tc-99m]pertechnetate and returned after 3 h for a repeat planar radionuclide ventriculography without administration of additional tracer. Results The average initial LVEF was 35.1 +/- 18.6%-point (range, 12%-point to 68%-point). The mean difference of the LVEF between the initial planar radionuclide ventriculography and the repeat planar radionuclide ventriculography was 2.8% +/- 6.3% (range, - 11.8% to 13.3%, P= NS). The correlation between both measurements was significant with a correlation coefficient of 0.995 (P Conclusion Repeated radionuclide ventriculography with a 3 h interval using a single standard dose of 500 MBq of [Tc-99m]pertechnetate is highly reproducible and will be useful for monitoring the effect of positive inotropic interventions.

The purpose of this study was to appraise the value of PET in the assessment of the effect of supposedly proangiogenic new therapies such as gene therapy with vascular endothelial growth factor (VEGF) gene and endomyocardial laser therapy. Methods: Thirty-five patients with end-stage coronary artery disease and class III (Canadian Cardiovascular Society) angina were included. Myocardial ischemia was evaluated with dipyridamole PET scanning and exercise tolerance with bicycle ergometry. Ten patients were treated with naked plasmid DNA encoding for human VEGF(165) (VEGF) and 12 patients were treated with laser therapy (direct myocardial revascularization [DMR]) using an electromechanical mapping system. Thirteen patients were treated with standard medical therapy (control). Results: In both active treatment groups, angina was reduced in most subjects, except in 2 VEGF and 5 DMR patients. In the control group, no improvement in anginal classification was found, except in 3 subjects. On the PET scan, solely in the VEGF group, the stress perfusion was significantly improved (from 57 +/- 33 to 81 +/- 55 mL/min/100 g; P = 0.031). Furthermore, in the VEGF group, the number of ischemic segments was reduced from 274 +/- 41 to 234 +/- 48 segments (P = 0.004) but not in the DMR group (from 209 +/- 43 to 215 +/- 52 segments) or in the control group (from 218 +/- 18 to 213 +/- 28 segments). Bicycle exercise duration showed slight nonsignificant changes in the VEGF group (from 3.6 +/- 2.0 to 4.6 +/- 2.1 min), in the DMR group (from 5.1 +/- 1.5 to 4.7 +/- 1.3 min), and in the control group (from 3.3 +/- 1.8 to 3.5 +/- 2.3 min). Conclusion: PET showed that intramyocardial gene therapy with the human VEGF(165) gene in contrast to laser DMR treatment effectively reduces myocardial ischemia.

The aim of this study was to compare left ventricular (LV) volumes and regional wall motion determined by PET with those determined by the reference technique, cardiovascular MRI. Methods: LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), and LV ejection fraction (LVEF) were measured and regional wall motion was scored in 38 patients with chronic coronary artery disease by both gated F-18-FDG PET and MRI. A 9-segment model was used for PET and MRI to assess regional wall motion. Results: Good correlations were observed between MRI and gated PET for all parameters (r values ranging from 0.91 to 0.96). With PET, there was a significant but small underestimation of LVEDV and LVEF. Mean+/-SD LVEDV, LVESV, and LVEF for MRI were 131+/-57 mL, 91+/-12 mL, and 33%+/-12%, respectively, and those for gated PET were 117+/-56 mL, 85+/-51 mL, and 30%+/-11%, respectively. For regional wall motion, an agreement of 85% was found, with a kappa-statistic of 0.79 (95% confidence interval, 0.70-0.89; SE, 0.049). Conclusion: LV volumes, LVEF, and regional wall motion can be assessed with gated F-18-FDG PET and correlate well with these parameters assessed by MRI.

Planar gated blood-pool imaging (GBPI) is a standard method for non-invasive assessment of left ventricular (LV) function. Gated blood-pool single photon emission computed tomographic (GBPS) data acquisition can be accomplished in the same time as GBPI, with the benefit of enabling visualization of all cardiac chambers simultaneously. The purpose of this investigation was to evaluate the degree to which automated and manual LVEF calculations agree with one another and with conventional GBPI LVEF measurements. GBPI studies were performed in 22 consecutive, unselected patients, followed by GBPS data acquisition. GBPS left ventricular ejection fraction (LVEF) calculations were performed by available software (NuSMUGA, Northwestern University, Chicago, IL) automatically and manually, using all LV gated short axis slices. Automatic LVEF assessed by GBPS correlated well with conventional planar GBPI (r = 0.88, P

Background: In comparison with planar imaging gated blood-pool single photon emission computed tomography (GBPS) has the advantage of separating left and right ventricle. The purpose of this investigation was to evaluate the right ventricular ejection fraction (RVEF) calculations by GBPS software ('NuSMUGA(TM)', Northwestern University, Chicago, IL) in comparison to first-pass radionuclide angiography (FPRNA). Methods: In 22 consecutive patients FPRNA and GBPS acquisition was performed. GBPS RVEF calculations were manually and automatically performed, using all gated short-axis-slices of the right ventricle. Results: Automatic RVEF assessed by GBPS did not correlate with conventional FPRNA (r = 0.40, p = 0.065). Mean FPRNA RVEF was 55 +/- 10% and mean GBPS automatic RVEF was 32 +/- 8%. Also manual GBPS RVEF did not correlate with conventional FPRNA (r = 0.41, p = 0.055). Mean RVEF measurement by manual GBPS was 33 +/- 8%. Manual GBPS RVEF values correlated well with automatically determined GBPS RVEF values (r = 0.96, p

Dual isotope simultaneous acquisition single photon emission computed tomography (DISA SPECT) offers the advantage of obtaining information on myocardial perfusion using Tc-99m-sestamibi (Tc-99m-MIBI) and metabolism using F-18-fluorodeoxyglucose (F-18-FDG) in a single study. The prerequisite is that the Tc-99m-MIBI images are not degraded by scattered 511 keV photons or poor count statistics due to the lower efficiency of the extra high energy (EHE) collimator. Therefore, we compared the registered 99mTc-MIBI uptake and image quality of DISA and single isotope acquisition. Furthermore, we investigated whether DISA yields additional information for the assessment of myocardial viability in comparison with rest-stress Tc-99m-MIBI. Nineteen patients with known coronary artery disease and irreversible perfusion defects on previous rest-stress MIBI test studies were investigated. After oral glucose loading and simultaneous injection of 600 MBq of Tc-99m-MIBI and 185 MBq of F-18-FDG at rest, DISA was performed using energy windows of 140 (+/-15%), 170 (+/-20%) and 511 keV (+/-15%). Planar 140 keV images were corrected for scatter by subtraction using the 170 keV window. The single and dual isotope Tc-99m-MIBI images were both displayed in a polar map with 128 segments normalized to maximum counts. F-18-FDG and Tc-99m-MIBI images were visually scored for a perfusion-metabolism mismatch pattern using nine regions per heart. There was an excellent correlation (r = 0.93, P

A 52-year-old woman with dextrocardia was evaluated for chest pain. To exclude myocardial ischemia, she underwent a 2-day rest and bicycle stress myocardial perfusion study with 600 MBq (16 mCi) Tc-99m sestamibi. The rotational direction of the perpendicularly positioned camera heads was fixed and adaptation to a right positioned heart was not possible, so the images were acquired in the usual manner. Emission scans were corrected for tissue attenuation by a transmission scan during reconstruction. The noncorrected short axis slices showed two moderately deep (60% of peak activity) irreversible defects in the inferolateral and septal wall. After attenuation correction, both defects disappeared almost completely. Gated SPECT imaging showed a normal contraction and thickening of the functional left ventricle, with an ejection fraction of 69%. This case shows that in dextrocardia, where normal attenuation is different from what readers are used to, attenuation correction can correctly discriminate between infarction and tissue attenuation artifacts.