In busy nuclear medicine departments, the F+0 protocol for diuretic renography is routinely used to shorten the acquisition time. The aim of this study was to evaluate the influence of the F+0 protocol on the split renal function (SRF) during a dynamic renal scan using technetium-99m diethylene triamine pentaacetic acid (Tc-DTPA) compared with that using the standard technetium-99m dimercaptosuccinic acid (Tc-DMSA). A total of 102 patients referred for a dynamic renal scan for varied etiologies were divided into two groups: the F+0 group, comprising 53 patients who were injected with furosemide just before Tc-DTPA injection, and the F+10 group, comprising 49 patients who were injected with the diuretic at the 10th minute after radiotracer injection. All patients were also subjected to a static cortical Tc-DMSA scan with geometric quantification of SRF. A highly significant statistical difference (P<0.001) was obtained on comparing the mean value of the difference in SRF calculated using DTPA and DMSA between the F+0 and F+10 groups, being 5.0±2.6 and 1.5±0.6%, respectively. All 49 patients in the F+10 group had a difference in split function of 5% or less, whereas 17/53 patients representing 32.1% of the F+0 group had a difference in SRF of greater than 5%. Early (F+0) furosemide injection before administration of Tc-DTPA has a significant influence on the estimation of SRF of the diseased kidney (either obstructed or functionally impaired) when compared with furosemide injection after standard Tc-DMSA administration. Care should be taken during interpretation of the scan findings when accurate split function is required.

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Background Atherosclerosis is an inflammatory disease of the inner wall of large and medium-sized arteries. The progress of atherosclerosis based on a lot of factors, including systemic involvement of disease, the precise vascular arterial affection, and the degree of flow obstruction. We aim in this study to estimate the FDG uptake of the aortic wall in the early and delayed imaging and to correlate this with the morphologic changes detected by CT. Results This is a prospective study that was performed through 1 year. The study included 50 patients [30 males (60%) and 20 females (40%)] with male to female mean ratio 1.5:1 and their mean age 58.3 ± 15.7 years. Each patient underwent dual time-point 18F-FDG PET CT imaging at ~ 60 min (Early images) and 180 min (delayed images) after the administration of 18F-FDG. For each patient, the global 18F-FDG uptake in the aorta was determined by manually drawing regions of interest (ROIs) around the outer part of the arterial wall on every slice of the attenuation-corrected transverse PET CT images. Per-patient, per-time-point, per-vessel, and per-ROI radiotracer decay-corrected and body weight-corrected SUVs were calculated, resulting in a single mean value of maximum SUV for the aorta. The aortic wall FDG uptake was measured in both early and delayed images and expressed in terms of SUVmax. Then Retention index percentage of the aorta was measured. The retention index percentage was calculated by subtracting the SUVmax in early images from the SUVmax in delayed images and dividing by SUVmax in early images. Conclusion Aortic wall FDG uptake can be used as an additional parameter as well as a biomarker on evaluation of the arterial atherosclerotic activity. Delayed post 3 h FDG imaging is more accurate than the routine early post 1 h imaging in evaluating the atherosclerotic activity.

Objective:To detect subclinical peripheral vascular disease in obese Egyptian patients and establish relations between obesity, metabolic risk factors, and PVD.Methods:This was a prospective case-control study including 100 obese patients (BMI >30) (G1). In addition, 100 age and sex matched non-obese healthy subjects as a control group (G2). Both groups were subjected to duplex ultrasound, Radionuclide muscle scan. Angiography was done for 17 patients.Results:The image pattern of 99mTc-MIBI muscles uptake was studied and perfusion reserve (PR%) was calculated in (G1) and (G2). Comparison between the two groups showed statistically significant difference (P < 0.001) as regarding laboratory findings. Patients were categorized according to PR% into +ve for ischemia (mean PR% was 28.4 ± 20.3) and -ve for ischemia (mean PR% was 65.0 ± 11.4). Among (G1) 64 patients positive for ischemia by both PR% and Doppler, 36 patients were negative by Doppler and 22 of them were positive for ischemia by PR%. Angiography was done for 17 of them and proved ischemia in all of them.Conclusion:The Tc-99m sestamibi muscle scan can be used as a screening and diagnostic tool of preclinical atherosclerosis in obese patients.

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