Objectives:Asurvey of nuclear medicine services in Saudi Arabia carried out to provide a baseline data information about the practice of Nuclear medicine (NM) by the beginning of 2018. Methods: An electronic questionnaire was sent to every NM department in Saudi Arabia. Information requested included the equipment, manpower and type of examinations performed. Results:All the 58 NM services in Saudi Arabia had responded to the questionnaire by October 2018. The overall functioning manpower included 65 NM physicians, 190 NM technologists, 41 nuclear physicists, and only 9 radio pharmacists. At the end of year 2017 there were 21 PET/CT machines in Saudi Arabia (15 machines in Riyadh, 4 in Dammam and 2 in Jeddah), 55 SPECT/CT, 35 SPECT and Gamma camera Machines, and 77 DEXAmachines. When adjusted to population, we found 0.6 PET/CT Unit per 1 M people, 3.4 total units (PET and SPECT Cameras) per 1 M people. Conclusion: The need for reorganizing the distribution of nuclear medicine services including the cyclotrons to cover the whole kingdom equally. Activation of Saudi Society of Nuclear Medicine (SSNM) is mandatory for establishing well recognized Nuclear medicine residency training program including other academic and scientific activities.

Objectives To assess diagnostic accuracy and added value of dual time point 18 F-FDG PET/CT after gastric distention using oral water in differentiating malignant from benign gastric lesions. Methods Patients (n = 30, 19 males, mean age 58.6 ± 16.4 years). All patients are known or suspected oncology patients. All patients underwent whole body 18 F-FDG PET/CT scan and 2 h delayed PET/CT abdominal images following oral water gastric distension. The best cut off values for early SUVmax (SUVmax1), delayed SUVmax (SUVmax2) and SUVmax2-SUVmax1 (ΔSUVmax) to differentiate benign from malignant lesions were set based on ROC analysis. Data analyzed included in addition; age, sex and 18 F-FDG uptake pattern in delayed images. Suspicious gastric lesions were correlated with biopsy in 18 patients (60 %) and with clinical and follow-up imaging ( 18 F-FDG PET/CT, CT or MRI) in 12 patients (40 %). Unpaired t -test was used to compare the mean deference in continuous variables between patients with gastric malignancy and those with benign gastric lesions. Fisher’s exact test was used to analyze categorical variables. Logistic regression analysis was performed to identify the most powerful factors to predict malignant lesions. Results Fifteen patients (50 %) had confirmed malignant gastric lesions. Patients with confirmed gastric malignancy were older (65 ± 13 vs 52 ± 17; p = 0.023) and had significantly higher mean ΔSUVmax (1.29 ± 1.76 vs −0.89 ± 1.59; p = 0.003). The mean SUVmax1 (6.99 ± 6.66 vs 5.31 ± 2.53; p = 0.367) and SUVmax2 (8.29 ± 7.41 vs 4.44 ± 3.34; p = 0.077) although both higher in patients with malignant lesions, they did not reach statistical significance. Sensitivity, specificity, PPV, NPV, and accuracy to detect malignant gastric lesions were highest for lesions with localized uptake pattern in delayed images post water oral contrast as well as for lesions with ΔSUVmax>0. Regression analysis revealed both variables as independent predictors for malignant lesions with odd ratios of 22.9 and 9.5 respectively and final model Chi-Square of 19.9 (p < 0.0001). The model correctly identified 12/15 (80 %) malignant lesions and 13/15 (86.7 %) benign lesions with 2 false positives confirmed as chronic active gastritis with helicobacter pylori and 3 false negatives including 1 signet ring gastric cancer and 1 low grade gastrointestinal stromal tumor (GIST), both with poor 18 F-FDG uptake. Conclusion Localized uptake pattern in delayed PET/CT images following gastric distention with oral water contrast as well as ΔSUVmax>0 are powerful independent variables to identify malignant gastric lesions with fairly high sensitivity and reasonable accuracy. Malignancies with inherently low 18 F-FDG avidity are the main cause of false negatives while active gastritis is th...

Granulomatosis with polyangiitis (GPA) can be classified as classic triad of organ involvement consisting of lungs, upper respiratory tract/sinuses, and kidneys; limited which is not having the full triad; or widespread with additional organ involvement for example prostate, spleen, skin, eyes or peripheral nervous system and occasionally other organs. GPA is associated with increased 18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography/computed tomography (PET/CT). PET/CT has the advantages of whole-body imaging and detecting metabolic abnormality before structural changes. FDG PET/CT is used to assess the extent of the disease in GPA and can detect site of occult disease involvement where there are metabolic evidence of defined organ involvement with no CT or clinical evidence. This may result in upgrading of the disease from limited to classic triad or from classic triad to widespread.

No abstract

No abstract