ANNALS OF NUCLEAR MEDICINE

The purpose of the study was to determine the lung toxicity caused by amiodarone (AD) and bleomycin (BLM) in rats, by means of Tc-99m HMPAO lung scintigraphy. Thirty albino rats were randomly divided into five groups. After AD or BLM was dissolved with isotonic saline (SF), a 0.5 ml solution was applied to the right bronchus via a catheter. Group 1 (n = 5 rats) received a single dose of AD, group 2 (n = 5) received two doses of AD, group 3 (n = 9) received BLM, group 4 (n = 3) received hydrochloric acid (HCl), and group 5 (n = 8) received SF. Rats in groups 1, 2, 3 and 5 were given 37 MBq Tc-99m HMPAO from the tail vein on days 7, 14, 21 and 28, and at 4 and 24 h in group 4. Static images of 10 min duration were obtained at 30 and 60 min by a double-headed gamma camera (Infinia, GE, Tirat Hacermel, Israel) on 256 x 256 matrix. Regular regions of interests were drawn over the right lung (RL), left lung (LL) and the liver (Li), and lung/liver (L/Li) ratios were calculated. After the scintigraphic imaging procedures were completed, rats were killed. Lung tissues were evaluated on a scale of (+) to (+++++) for edema, alveolar structural integrity and infiltration by inflammatory cells. Groups 2 and 3 showed statistically significant differences in RL/Li and LL/Li ratios, whereby RL/Li was higher than LL/Li (p 0.05). In histopathological examination, minimal damage or artifacts were observed in group 5. In group 4, almost all pathological findings were present in the right lung. Statistically significant (p < 0.01) histological differences were found when groups 1 and 5 were compared. More significant (p < 0.001) pathological effects were noted when groups 2 and 3 were compared to both groups 5 and 1. Injury was more prominent in the lung tissues of the control rats that were given HCl. Increased RL/Li ratios and histopathological findings were consistent. Tc-99m HMPAO lung scan are found to be useful in the identification of patients with lung toxicity. The simplicity of the procedure and lower radiation exposure are the advantages of Tc-99m HMPAO lung scan

NUCLEAR MEDICINE COMMUNICATIONS

Aim Behcet's disease (BD) is a multisystem disorder that is characterized by vasculitis, and consists of a triad of recurrent ulcers of the oral and genital mucosa with relapsing uveitis. The prevalence of pulmonary involvement varies in the range of 1-10% in various studies, and its complications are severe and life threatening. To objectively assess the degree of pulmonary vascular endothelial damage in BD, the lung uptake, and the clearance rate of technetium-99m-hexamethylpropylene amine oxirne (Tc-99m-HMPAO) were determined. Methods Twenty-three nonsmoking patients with BD (10 female, 13 male) and 11 (six female, five male) healthy nonsmoking controls underwent Tc-99m-HMPAO lung scanning, pulmonary function tests (PFT), chest radiograph examination, contrast-enhanced spiral chest computed tomography scanning, and high-resolution computed tomography examinations. Immediately after the bolus injection of 740 MBq of Tc-99m-HMPAO posterior sequential images were obtained at 1-s intervals for 150s and subsequent images were obtained at one frame per minute (min) over a 10-min period, using a double-headed gamma camera equipped with a low-energy all-purpose parallel hole collimator. Dynamic images were used to calculate the Tc-99m-HMPAO lung clearance rate (T(1/2)). Simultaneously, a static anterior image, including a large pad of the liver, was obtained of 5-min duration at 10 min after the injection. Regular regions of interests were drawn over the midportion of the right lung and the highest activity area of the liver parenchyma was selected and lung/liver (L/Li) uptake ratios were calculated to represent the degree of pulmonary vascular endothelial damage. Results Chest radiograph, high-resolution computed tomography, and computed tomography findings in patients with BD were nonspecific for BD. There was also a statistically significant difference between patients with BD (30.26 +/- 10.55s) and normal controls (19.53 +/- 6.24s) on their T(1/2) values (P=0.0004). The results show that the L/Li ratios on the Tc-99m-HMPAO lung scan were significantly higher in patients with BD (0.60 +/- 0.19) than those in normal controls (0.39 +/- 0.07) (P=0.0021). Using a cutoff value of 0.50, 15 of 23 (65%) patients with BD had increased L/Li ratios. No correlation was found between the mean T(1/2) values of Tc-99m-HMPAO clearance and the PFT in patients with BD. The L/Li ratios were not correlated with PFT in patients with BD. Conclusion The degree of pulmonary vascular endothelial damage was represented as increased L/Li ratios and decreased lung clearance rate measured on the Tc-99m-HMPAO lung scan in patients with BD. Our results indicated that determining the T(1/2) values and the L/Li ratios on Tc-99m-HMPAO lung imaging should be an objective method to assess subclinical pulmonary damage even in the early stages of BD in the patients. Nucl Med Commun 32:363-368 (C) 2011 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins

NUCLEAR MEDICINE COMMUNICATIONS

Objective Nuclear medicine procedures are often performed in close-time proximity to bone densitometry studies. The purpose of this study was to determine the effects of Tc-99m-hexakis-2-methoxyisobutyl isonitrile (MIBI) and Tc-99m-methylene diphosphonate (MDP) on the accuracy of bone mineral density (BMD) measurements performed using dual-energy X-ray density. Methods The effect of a diagnostic dose of Tc-99m-MIBI on BMD estimations in the lumbar spine and the left total hip was assessed in 30 patients (19 female, 11 male; mean age: 55.5 +/- 10.5 years) by using a Lunar DPX-NT scanner. Thirty patients, admitted to the nuclear medicine department for bone scintigraphy (15 female, 15 male; mean age: 56 +/- 15.92 years), were included into the study. Each patient underwent dual-energy X-ray density assessment for which a Lunar DPX-NT scanner was used before and 2 h after intravenous injection of (99m)-Tc-MDP (925MBq) and Tc-99m-MIBI (1110MBq). BMD measurements were calculated from lumbar spine (including L2-4) and left hip (including femoral neck, trochanter, and total hip). For statistical analysis, the Wilcoxon test was used and a P value of less than 0.05 was accepted as statistically significant. Results According to Wilcoxon's statistical test, we found extremely significant changes on the measured BMD, T-score, before and 2 h after the injection of Tc-99m-MIBI for lumbar spine and left hip in 30 patients. We found statistically significant decrement on measured BMD from lumbar spine and trochanter before and 2 h after the injection of Tc-99m-MDP. Although MDP BMD values in femoral neck and total hip were decreased after the injection of Tc-99m, they did not reach a statistically significant value. The comparison of pre-T-score and post-T-score values showed a statistically significant decrease after the injection for only L2-4 lumbar spine (P=0.002), but left hip of pre-T-score and post-T-score values did not reach a statistically significant value. Conclusion In this study, it was determined that measured BMD values are decreased in lumbar spine for all patients. The magnitude of the effect is dependent on the location of the activity. We assume that some radioactivity from (TC)-T-99m is counted by the densitometer's detector, thus resulting in a decrease in the measured BMD. Scintigraphy and bone densitometry should be performed on different days to avoid artifactual reduction in BMD measurements. Nucl Med Commun 30:445-448 (C) 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins