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Dipyridamole has extensively been administered as a substitute for physical activity in cardiovascular assessment. The aim of this study was to evaluate the association of dipyridamole side effects with hemodynamic oscillations, scanning results, and electrocardiography (ECG) findings. Methods: Overall, 590 patients referred to the nuclear medicine center for myocardial perfusion imaging were evaluated for adverse dipyridamole effects concurrent with a low level of exercise. Before and during dipyridamole infusion, the patients' vital signs, electrocardiogram, heart rate, systolic blood pressure, and diastolic blood pressure were monitored; all patients underwent stress-rest 99m Tc-sestamibi gated SPECT using a 2-d protocol. Results: Eighty-eight patients (14.9%) experienced at least one side effect during dipyridamole infusion, and abnormal ECG and scan results were observed in 32.4% and 48.6% of patients, respectively. We observed a positive correlation between a higher incidence of chest discomfort, headache, and dyspnea and abnormalities on ECG and myocardial perfusion imaging. In addition, these 3 side effects were also associated with a higher postinfusion heart rate, lower preinfusion systolic blood pressure, and lower postinfusion diastolic blood pressure. There were significant differences between pre-and postinfusion heart rate, preinfusion systolic blood pressure, and postinfusion diastolic blood pressure among patients with or without side effects, whereas no significant difference was observed in any of the hemodynamic parameters between patients with normal and abnormal ECG results or myocardial perfusion imaging results. Conclusion: This study demonstrated a correlation between hemodynamic variables and side effects but not with imaging findings or ECG findings. The administration of dipyridamole during perfusion scintigraphy has extensively been applied to simulate the effects of physical activity in patients who are incapable of performing a conventional exercise test (1-3). The addition of a symptom-limited exercise test is also considered safe and efficient. Compared with dipyridamole infusion alone, exercise added to dipyridamole infusion has been shown to result in fewer noncardiac side effects, the same prevalence of angina pectoris, and a higher incidence of ST segment changes (4).Dipyridamole, by itself, can cause hypotension, dyspnea, dizziness, and electrocardiography (ECG) abnormalities; however, simultaneous dipyridamole administration and scanning should be treated as a distinct situation and demands its own risk assessment. Several studies have evaluated the safety and diagnostic precision of dipyridamole-thallium imaging in subjects with suspected coronary artery disease (5,6).The purpose of this study was to assess the incidence of dipyridamole side effects and their association with hemodynamic changes, scanning results, and ECG findings. MATERIALS AND METHODS Participants and Study DesignOverall, 590 patients (mean age 6 SD, 57 6 11 y) who underwent myocardial perfusion scanning...

These data showed that redistribution and reverse redistribution of 99mTc-sestamibi post thrombolytic therapy can be used as a marker of viability to predict the recovery of segmental wall motion abnormality (stunning), as well as the improvement of segmental perfusion uptake. This study also demonstrates that the resting 99mTc-sestamibi SPECT can be used for an approximate assessment of LV function status and can predict the recovery of jeopardized myocardium function after thrombolytic therapy.

Differentiated thyroid carcinoma is rare in patients younger than 21 years, especially in children, but it is associated with a greater risk of metastases and recurrence. The aim of our study was to compare the characteristics, clinical course, and outcome of the disease between young children (≤16 years) and adolescents (17-21 years). We reviewed the medical records of 62 young children and adolescents (47 females, 15 males, ≤21 years) with DTC who were diagnosed between 1990 and 2010 and admitted for radioiodine therapy, and compared the histopathologic features, amount and session(s) of radioiodine administration, and outcome in both groups. Young children presented with larger tumor size, more aggressive pathological features, higher incidence of locoregional and distant metastasis, and needed more admissions, and higher amounts of radioiodine for treatment. While there were more disease-free patients at the end of follow-up in the adolescents, the number of patients with stable or progressive disease was higher in younger group. Based on the results of our study, we support the more aggressive approach to DTC treatment in young children, including total thyroidectomy along with more extensive cervical lymph node dissection, L-T4 therapy in suppressive doses, and multiple sessions of postsurgical radioiodine therapy as necessitated.

Diabetic foot infection is the most common etiology of nontraumatic amputation of the lower extremities, and early diagnosis is of great importance in its management. The aim of this prospective study was to evaluate the strength of 99m TcIgG scintigraphy in diagnosis of osteomyelitis of the diabetic foot and to compare 99m Tc-IgG scintigraphy with 99m Tc-methylene diphosphonate (MDP) scintigraphy. Methods: A prospective university hospital-based study was performed over 24 mo. Eighteen patients with type II diabetes and foot ulcers (15 men and 3 women; age range, 45-80 y) were referred for imaging because of clinically suspected osteomyelitis. Early (5-h) and late (24-h) 99m Tc-IgG scanning and 3-phase skeletal scintigraphy were completed for all patients at a 3-to 4-d interval.Regions of interest over the involved bony sites and the contralateral normal sites were drawn, and the abnormal-to-normal ratios were acquired for both 99m Tc-IgG and 99m Tc-MDP studies. Results: From a total of 23 lesions, we observed 10 sites of osteomyelitis, 10 sites of cellulitis, and 3 sites of aseptic inflammation confirmed by MRI, clinical presentation, histopathologic examination, and follow-up evaluation as a gold standard. Both 99m Tc-IgG and 99m Tc-MDP scanning showed excellent sensitivity for diagnosis of osteomyelitis, but the specificity was significantly lower (69.2% and 53.8%, respectively). Sensitivity, specificity, and accuracy in the diagnosis of osteomyelitis were, respectively, 100%, 53.8%, 73.9% for 99m Tc-MDP scanning; 100%, 69.2%, 82.6% for 5-h 99m Tc-IgG scanning; and 60%, 76.9%, 69.5% for 24-h 99m Tc-IgG scanning. There was no significant difference between the semiquantitative indices of 5-h and 24-h 99m Tc-IgG scanning for inflammation, cellulitis, and osteomyelitis. Conclusion: Although both 99m Tc-IgG and 99m Tc-MDP scintigraphy have high sensitivity for the diagnosis of osteomyelitis, the specificity of these studies is poor. For 99m Tc-IgG scintigraphy, 5-h images appear to be adequate, and there is little benefit to performing additional imaging at 24 h. Peri pheral neuropathy and metabolic and vascular disorders are important contributing factors leading to infection of obscured wounds in diabetic patients (1,2). When there is evidence of osteomyelitis, invasive procedures are needed to avoid amputation (3). Radiographic evaluation is not sensitive for the development of osteomyelitis, whereas labeled leukocyte imaging followed by bone marrow scintigraphy, although both sensitive and specific, is labor-intensive and limited by the risks associated with handling blood products (4). 111 In-IgG and 99m Tc-methylene diphosphonate (MDP) scintigraphy can be helpful for the diagnosis of inflammation and infection (5-11).The aim of this prospective study was to assess the role of 99m Tc-IgG scintigraphy in the diagnosis of osteomyelitis in the diabetic foot and to compare 99m Tc-IgG scintigraphy with 99m Tc-MDP scintigraphy. In addition to qualitatively assessing the 99m Tc-MDP and 99m Tc-IgG studies, we have...