Sanja Dugonjic

Estimation of 99mTc-ciprofloxacin accumulation indexes in bone and joint bacterial infections.

BACKGROUND/AIM 99mTc-ciprofloxacin is a radiopharmaceutical preparation sintetized to improve diagnostic accuracy of bacterial infections in human tissues. It is mostly applied in diagnosis of bone and joint infections. Many papers have confirmed its sensitivity to infection, but newer papers argued its specificity. The aim of this study was to compare the results of visual analysis of scintigrams to semiquantitative calculations of accumulation indexes with the assumption that calculation of indexes would improve the specificity for bone and joint infections. METHODS We examined 40 patients, 25 with confirmed bone and joint bacterial infections and 15 patients with bone and joint diseases without bacterial infection. Scintigraphy was performed 5 minutes, 1, 4 and 24 hours after intravenous (i.v.) injection of 99mTc-ciprofloxacin. Scintigrams were analysed visually and by calculation and comparation of accumulation indexes values. RESULTS Visual sensitivity was 94%, but specificity only 47%. Index calculation achieved much higher specificity (100% after 1, 4 and 24 hours for cut off value of 1.50). All basic index values (5 min) in the patients with infections increased in 24 hours. In 8 patients without infection occured a slight increase and in 7 patients decrease of basic index values. CONCLUSION Calculation of accumulation index values is needed in the use of 99mTc-ciprofloxacin scintigraphy as it is the only way to improve specificity for bacterial bone infections. Visual interpretation of results is sensitive, but not specific due to accumulation of the drug in a high percent of non infected bone and joint lesions.

Incidence and imaging characteristics of skeletal metastases detected by bone scintigraphy in lung cancer patients

BACKGROUND/AIM Detection of metastatic bone disease by skeletal scintigraphy is a classical application of nuclear medicine in cancer patients. Detection of bone metastases in patients with lung cancer is necessary for an appropriate treatment modality. The aim of this study was to report the frequency and imaging characteristics of bone metastases detected by bone scintigraphy (BS) using technetium-99m phosphonates in patients with lung cancer. METHODS We retrospectively analyzed a total of one hundred patients (78 males and 22 females), mean age of 63.3 years, with the diagnosis of lung cancer, who underwent BS during a three-year-period (2003-2005). Scintiscans were classified as positive, negative and suspicious with regard to the presence of bone metastases. RESULTS The incidence of positive, negative and suspicious findings were 57%. 32% and 11%, respectively. Out of 57 patients with bone metastases, 51 had multiple asymmetric foci of increased tracer activity localized in the ribs, spine, extremities, pelvis, sternum, scapula and skull in 72%, 54%, 49%, 37%, 12%, 9% and 5% of scans, respectively. BS revealed solitary metastases in 6 of the patients. The lesions were located in the lower limbs in three patients and in the upper limbs, pelvis and sternum in the remaining three patients. CONCLUSION Bone scintigraphy plays a significant role in staging and selecting of patients for curative lung surgery. Due to the fact that metastatic involvment of the extremities was frequently shown, our study suggests that systematic inclusion of the limbs in BS acquisition should be obligatory.

Estimated Dose to Family Members of Patients Treated with Radioiodine.

Patients who receive therapeutic amount of 131I are potentially significant source of radiation to their family members and general public. The aim of this study was to estimate effective dose to family members of patients treated with radioiodine, released after 3 d of hospitalization and to compare with dose constraints proposed by international recommendations. The thermoluminescence dosemeters (TLD 100) and Radiation Dose Assessment Resource (RADAR) software were used for assessment of effective doses to 60 family members of the same number of hyperthyroid and thyroid carcinoma patients. Estimated effective doses were well below recommended dose limits except in a few cases. RADAR-calculated doses were higher than doses measured by TLD. Hyperthyroid patients should continue to be treated on outpatient basis but they should be well informed for their further behavior to provide minimal radiation hazard for the people in their environment.

Renal scintigraphy in infants with antenatally diagnosed renal pelvis dilatation

BACKGROUND/AIM Ureteropelvic junction obstruction and vesicoureteral reflux are the most frequent entities identified on the basis of antenatal hydronephrosis. The aim of this study was to determine the incidence and pattern of abnormal renal scintigraphy findings in postnatal investigation of children with antenatal hydronephrosis. METHODS Twenty-four infants (19 boys and five girls) presented with antenatal hydronephrosis and mild to moderate hydronephrosis on ultrasound in newborn period were referred for renal scintigraphy. Ten patients with vesicoureteral reflux documented on micturating cystoureterography underwent 99mTc-DMSA renal scintigraphy and 14 patients were subjected to 99mTc-DTPA scintigraphy. RESULTS Anteroposterior pelvic diameter on ultrasound ranged from 11 to 24 mm. Renal DMSA scans identified congenital scars in two boys with bilateral reflux of grade V and unilateral reflux of grade III. Relative kidney uptake (RKU) less than 40% was found in three, and poor kidney function (RKU less than 10%) in two patients. Significant obstruction was shown on DTPA diuretic renal scintigraphy in 6/14 patients. Some slowing in dranaige (T1/2 greater than 10 minutes) with no reduction in differential renal function was identified in three patients. Differential renal function less than 10% was obtained in one case. CONCLUSION A high percent of abnormal renal scintigraphy findings was obtained. Renal scintigraphy was useful in determination of underlying cause of antenatally detected hydronephrosis.