Iranian Journal of Nuclear Medicine
Volume:10 Issue: 2, 2003

Radioisotope scanning is very important in evaluation, diagnosis and proper treatment of urinary tract infection (UTI) and vesicoureteral reflux (VUR) because of high sensitivity of this technique and less radiation dose delivered to the patients. This is a descriptive cross-sectional study to determine the frequency VUR in a group of children aged 28 days to 14 years referred to our department with diagnosis of UTI. The radioisotope scanning was conducted for all of patient (30 patients) and the results were analyzed. The results showed that UTI is seen in wide age group and is usually associated with VUR. The above findings revealed the important role of radioisotope scanning in early diagnosis and subsequent treatment of UTI to detect VUR and prevent subsequent side effects in these patients.

Urinary tract infection (UTI) is a common disease in childhood specially in female. In this study 50 patients with stablished diagnosis of UTI were evaluated by both renal scan with Tc-99m DMSA and renal sonography. The study revealed that most urinary tract infections are in children, Female sex between 5-9 years of age. Therefore the most important complications (Renal scarring) are also common in this age-sex distribution. Occurance of renal scars increase with increasing the number of recurrent infections. Vesicoureteral reflux is one of the most improtant, common risk factors for renal scarring. Renal Tc-99m DMSA scan is more sensitive than renal sonography in detecting the renal scars.

This study evaluated the relationship between the location of the most severe coronary artery stenosis and the subsequent acute myocardial infarction (AMI). Of 1590 patients who were admitted with a diagnosis of AMI, we identified 44 patients who had undergone previous myocardial perfusion SPECT. Thirty-one of these patients also had previous coronary angiography. The relationship between the location of the myocardial perfusion defects, the coronary artery stenosis and site of subsequent AMI were studied in these patients. The concordance between the location of the most severe reversible defects detected by SPECT and the site of subsequent AMI was 71% (k=0.499). The concordance between the most severe stenosis detected by coronary angiography and the site of subsequent AMI was 64% (k=0.451). The culprit lesion is not always the one that is manifested by the most severe reversible perfusion defect or the most critical coronary stenosis. Myocardial SPECT and coronary angiography can peredict the location of a future AMI in 71% and 64% of patients respectively. The percentage is higher when the interval between investigations and subsequent AMI is <3 month, for moderate to severe perfusion defects and for 90-99% coronary stenosis.

patients with previous history of radiotherapy of the head for Tinea Capitis] Source:, 2002;(18):21-27:Persian. In spite of large number of studies regarding relation between thyroid cancer and childhood irradiation, contraversy still exists management of these patients. This study tries to find optimal method of thyroid evaluation in this group. Methods and patients: In a recall program using mass media in Khorasan, all patients with childhood irradiation were invited for thyroid evaluation. One hundred and eighty patients with previous history of radiation for Tinea Capitis were studied using thyroid examination, thyroid sonography and thyroid scintigraphy. FNAB was performed in all patients with palpable nodules and surgery was recommended. Eighty two cases out of 179 patients (45.8%) had nodules in thyroid examination. The number were 85 from 166 (51.2%) in sonography and 75 from 165 (45.5%) in thyroid scintigraphy. Using Chi-square tests, no significant difference was noted in detection of thyroid nodules in different methods (P=0.78) as well as between the methods (P>0.5). Sonographically detected nodules which were not palpated or were not seen in scintigraphy, were <10 mm in size in most of cases. FNAB were performed in 60 patients which revealed benign pathology in 89.9% inadequate in 5% and suspicious for malignancy in other 5% of cases. Also 27 patients underwent surgery and pathological studies showed 3 cases (11.1 %) of papillary carcinoma. Conclution: This study revealed that sonography detects small nonpalpable nodules which are not clinically significant. Very high correlation between the results of thyroid examination and thyroid scintigraphy indicates adequacy of thyroid examination in these patients. We suggest to follow these patients with physical examination and FNAB and use thyroid scanning or sonography in doubtful cases only.

Radiolabeled monoclonal antibodies, have created new innovations in diagnosis, research and therapy of disease in last 2 decades. One of the serious limitation of applications of radiolabeled antibodies in vivo is relatively low target to background activity. Various strategies have been proposed to solve this problem including pre-targeting methods that was suggested in 1989. Regarding importance of monoclonal antibodies and radioisotopes, based on pre-targeting strategy, we have introduced new derivative of Biotin and DTPA to decrease background activity. DTPA-bio and new derivative (DTPA-bio-1OX) were labeled with ¹¹¹In, labeled compounds and injected through tail veins into Balb/c mice, and percent of injected dose per gram of blood (%ID/g of blood) was determined at 15, 30, 60, 120, 180, and 240 min after injection. Based on results,¹¹¹In-DTPA-bio rapidly cleared from serum, indicating molecular weight of label is increased causing delayed clearance from serum. Therefore, there is enough time for label to accumulate in the target tissues. With advent of second generation of monoclonal antibodies and antibody engineering, pretargeting methods have changed greatly. It seems that derivatives we introduced will have an important role in new pre-targeting methods.