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OBJECTIVE: Primary hyperparathyroidism (pHPT) is characterised by increased parathyroid hormone (PTH) secretion and consequently increased plasma calcium. During the last few decades parathyroid scintigraphy (PS), is applied in almost all patients with pPHT before surgery and specifically before minimally invasive parathyroidectomy. The aim of this study was to find the best cut-off levels of total plasma calcium and intact PTH (iPTH) that correlate with positive technetium-99m-methoxy isobutyl isonitrile (99mTc-MIBI) PS and with positive subtraction PS (SPS) in patients with pHPT and thus the positive diagnostic value of these PS. SUBJECTS AND METHODS: We studied 50 patients, operated for pHPT, aged from 22-78 years, (median age 60 years), 45 female and 5 male, with a total number of 57 parathyroid glands (PG), (46 adenomas and 11 hyperplasias). All patients underwent SPS before surgery. Static scintigrams of the head, neck and chest were performed 15min after the intravenous (i.v.) injection of 740MBq of 99mTc-MIBI. Late scintigrams of the head, neck and chest were performed 2h and 3h after the injection of 99mTc-MIBI. Four to 24h after the washout of 99mTc-MIBI from the parathyroid and the thyroid glands, we injected i.v. 185MBq of 99mTc-pertechnetate (99mTcP) and after 15min we performed the PS. Normalization and motion correction of the early 99mTc-MIBI scan and the 99mTcP followed. We then subtracted the 99mTcP from the 99mTc-MIBI scan. The areas of increased uptake on the 99mTc-MIBI scan visible at the early and late or at the subtraction images represented the hyperfunctioning tissue of the enlarged and hyperfunctioning parathyroid glands. Scintigraphic findings were graded subjectively, from 1 to 5 depending on the degree of the uptake of the radiopharmaceutical. Normal iPTH levels were between 10.0-65.0pg/mL and normal total plasma calcium between 2.13-2.65mmoL/L. RESULTS: Of all patients 12/50 and 38/50 had both PS positive grade 4 and very positive grade 5 findings respectively. In all patients iPTH levels ranged from 54 to 837pg/mL, median value 187.0±133.8pg/mL, and total plasma calcium ranged from 2.40 to 3.83mmoL/L, median value, 2.87±0.237mmoL/L. In 43 patients, both calcium and the iPTH levels were elevated. Strong positive correlation was found between scintigraphic findings and levels of iPTH: P=0.003. A significant relation between plasma calcium levels and different grades of scintigraphic findings was not found, although significant correlation was found between iPTH and plasma calcium levels (P=0.021). CONCLUSION: In patients with pHPT, the 99mTc-MIBI PS and the subtraction PS showed a strong correlation to iPTH (P=0.003) but not to total plasma calcium levels indicating the importance of both the 99mTc-MIBI and the subtraction parathyroid scans to indicate pHPT.

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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.

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OBJECTIVE: The purpose of this study was to evaluate damage of the kidney with technetium-99m-dimercaptosuccinic acid (99mTc-DMSA) scintigraphy in children with congenital hydronephrosis (CH) and the influence of other postnatal associated diagnoses on abnormal 99mTc-DMSA findings. SUBJECTS AND METHODS: 99mTc-DMSA scintigraphy in 54 children (17 girls and 37 boys), aged from 2 months to 5 years (median 11 months) with 66 congenital hydronephrotic renal units (RU) (42 unilateral hydronephrosis-29 boys and 13 girls; 12 bilateral hydronephrosis-8 boys and 4 girls) was performed. Male/female ratio was 2,2:1, unilateral/bilateral hydronephrosis ratio was 4:1. Hydronephrosis classified into three groups according to ultrasound measurement of the antero-posterior pelvic diameter APD): mild (APD 5-9.9mm) was present in 13/66RU, moderate (APD 10-14.9mm) in 25/66RU, and severe (APD≥15mm) in 28/66RU. Simple hydronephrosis was present in 15RU, and the postnatal associated clinical diagnosis were vesicoureteric reflux (VUR) in 21, pelviureteric junction (PUJ) obstruction in 7, pyelon et ureter duplex in 11, megaureter in 11 and posterior urethra valves in 1RU, respectively. Static renal scintigraphy was performed 2 to 3 hours after intravenous (iv) injection of 99mTc-DMSA using a dose of 50µCi/kg (1.85MBq/kg; minimal dose: 300µCi). Four views (posterior, left and right posterior oblique and anterior) were obtained with a head gamma camera "Orbiter" filtered with high resolution parallel whole collimator. All images were stored in an Pegasys computer with a matrix size of 256×256. The relative kidney uptake (RKU) between the left and right kidney was calculated as an average number counts from anterior and posterior view. Renal pathology was defined as inhomogenous or focal/multifocal uptake defects of radiopharmaceutical in hydronephrotic kidney or as split renal uptake of <40%, and poor kidney function was defined as split renal uptake <10%. Descriptive and analytical statistics (SPSS version 20.0) was performed. Analytical statistics implied the non-parametric Mann-Whitney test for determination of statistically significant difference between the normal and pathological findings on 99mTc-DMS scan. The default level of significance was P<.05. RESULTS: Our 99mTc-DMSA scintigraphy findings in children with ANH were: decreased or enlarged kidney with inhomogeneous kidney uptake radiopharmaceutical in 22, irregular shape kidney with inhomogeneous accumulation of radiopharmaceutical in 3, connected (fused) kidney in 1 patient, and poorly or nonvisual kidney in 14RU respectively (total 40/66RU with pathological 99mTc-DMSA finding, 60,6%). Relative accumulation in hydronephrotic kidney was less or equal to 40% in 17RU, less than 10% in 14RU and inhomogeneous radiopharmaceutical uptake with relative accumulation over 40% was detected in 9RU. Regular kidney morphology with homogeneous accumulation of radiopharmaceutical (normal DMSA scintigraphy finding) were found in 26/66RU (39,4%). Statistically significant correlation between the degree of the hydronephrosis (APD) and 99mTc-DMSA scan findings (P<0.001) and between the degree of the VUR and DMSA scan finding (P=0.002) was established. In our study, other associated diagnosis were not statistically correlated with pathological findings on 99mTc-DMSA scan due to low number of patients. CONCLUSION: On the basis of these results (60% pathological findings) we recommend DMSA scintigraphy in the evaluation renal pathology in children with congenital hydronephrosis. Greater number of patients is needed for the estimation of the associated diagnosis (other than VUR) influence on the renal parenchymal damage in children with CH.

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OBJECTIVE: Most difficult and very frequent complications of osteoporosis are vertebral compression fractures (VCF). Bone scintigraphy with 99mTc-phosphonates enables early detection of vertebral compression fractures in the first 72 hours of occuring. Typical scintigraphic findings is markedly increased radiotracer uptake in the linear pattern, throughout collapsed vertebral body. Bone scintigraphy is usefull in follow-up of vertebral fractures healing, showing reduction of radiotracer uptake in fractured vertebrae. In patients with osteoporosis and suspition of VCF, we detected compression vertebral fracture by bone scintigraphy and compare it with conventional radiography findings. PATIENTS AND METHOD: Bone scintigraphy was done in 40 patients with osteoporosis and suspition of compression vertebral fractures, 32 women and 8 men, mean age, 71 years. Three hours after iv. injection of 740MBq of 99mTc-DPD to the patients, a whole body scintigraphy was done. Standard radiographic views AP, lateral, and oblique were done in all patients. RESULTS: Radiography findings were positive for vertebral compression fracture in 28 patients (70%), and with bone scintigraphy in 36 patients (90%). In one patient with healed-old vertebral fracture, with positive radiographic finding, scintigraphic finding was negative. Bone scintigraphy incidentally diagnosed bone metastases in 3 patients. CONCLUSION: Bone scintigraphy has a very high sensitivity for detection of vertebral compression fractures in osteoporotic patients. Conventional radiography showed a much lower sensitivity and could not differentiate acute from old vertebral compression fractures.

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Our aim was to validate eight scintigraphic salivary gland (SG) parameters, as diagnostic parameters in patients with Sjögren's syndrome (SS). We used the standardized stimulated dynamic salivary gland scintigraphy (DSGS) protocol and correlated this with the unstimulated whole sialometry (UWS) functions. The DSGS and UWS tests meeting the European and the USA diagnostic classification criteria for SS were applied in twenty patients and in ten normal controls. The DSGS tests were performed 60min after the intravenous (i.v.) injection of 370MBq of technetium-99m-pertechnetate ((99m)TcO(-)4) and after per os stimulation with a 0.5g tablet of ascorbic acid administered 40min after the injection. Using time-activity curves, eight different parameters were calculated for each parotid gland (PG) and each submandibular salivary gland (SMG): a) time at maximum counts (Tmax), b) time at minimum counts (Tmin), c) maximum accumulation (MA), d) accumulation velocity (AV), e) maximum secretion (MS), f) maximum stimulated secretion (MSS), g) stimulated secretion velocity (SSV), and h) uptake ratio (UR). Values of UWS below 2.5mL/15min, were considered abnormal. All these parameters, as for the PG, showed significant abnormality in SS patients (P<0.001), especially of the secretion function. All SMG parameters also showed a significant abnormality (P<0.001), but especially of the accumulation function. There was a greater impairment of the above parameters in SMG than in PG in the SS patients. Sensitivity of the standardized DSGS was 100%, specificity 80%, negative prognostic value 100%, and positive prognostic value 91%. Sensitivity of UWS was 75%. In conclusion, this paper suggested that the best diagnostic parameters for the SS patients were those of: a) the maximum secretion, b) the maximum stimulated secretion for both the parotid and the submandibular glands, c) maximum accumulation and d) accumulation velocity of submandibular glands. The times at maximum and at minimum counts were non diagnostic.

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BACKGROUND/AIM: Parathyroid hyperplasia (PHP) is defined as an absolute increase in the mass of parenchymal cells of the parathyroid gland. PHP is classified as primary, secondary and tertiary. The enlargement of parathyroid glands (PG) is usually asymmetric, resulting in a "dominant" gland. In order to confirm the diagnosis, at least two glands should be examined histologically. Subtotal parathyroidectomy, i.e. removal of the three PG and leaving a small remnant of the forth, is the treatment of choice. High percent of PHP recurrence imposes the need for preoperative high sensitivity localizing procedures. Parathyroid scintigraphy localizes about 60% of hyperplastic glands. The aim of this study was to correlate findings of subtraction parathyroid scintigraphy (SPS) with weight, pathohistologic finding and oxyphil cell (OC) content of PG in patients with primary, secondary and tertiary parathyroid hyperplasia. METHODS: Twenty-seven patients with primary/secondary PHP underwent SPS before surgery. Scintigraphic results were graded from 1-5, in relation to the degree of uptake. SPS graded 3, 4 and 5 were considered positive. The number and weight of operated PG were evaluated macroscopically. Pathohistologic and cellular types were defined on standard stained hematoxylin-eosin slides. OC content was defined as a percent of OC and graded from 1 to 3: grade 1 < 10%, grade 2 > or = 10% and grade 3 > or = 20% of OC. RESULTS: SPS localized dominant gland in all patients with sensitivity 100%, and 51 from 73 hyperplastic PG, with sensitivity per gland of 70%. PG weighed 0.1 g to 6.7 g (median 1 g). A significant positive correlation (p < 0.0001) was found between the SPS results and PG weight. A significant positive correlation was found between PG weight and OC content (p = 0.0002). An insignificant correlation was found between SPS and OC content. Thirty-eight PG had < 10% of OC, 32 PG had > or = 10% and 3 PG had > or = 20% of OC. Four patients had diffuse PHP and 23 patients nodular PHP. There was no statistically significant difference in SPS results compared to hyperplasia type, and between OC content and hyperplasia type. A significant positive correlation (p = 0.05) was found between PG weight and hyperplasia type. CONCLUSION: A high positive correlation was found between SPS results and PG weight, PG weight and OC content and PG weight and hyperplasia type. Between SPS results and OC content, and between SPS results and hyperplasia type, an insignificant correlation was found. Our results showed that SPS is a reliable and very sensitive diagnostic tool in detecting abnormal PG in parathyroid hyperplasia, reaching 100% sensitivity in detecting a "dominant gland" and sensitivity per localized gland of 70%. Causes that affect increased uptake of liposolubile Tc99m radiopharmaceuticals (RF) in the hyperfunctional PG tissue and conditions which prevent RF admission into the PG cells still remain to be accurately and precisely determined.

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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.

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BACKGROUND/AIM: Primary hyperparathyroidism (pHPT) is an endocrine disease with the third highest incidence of all endocrine disorders after diabetes mellitus and hyperthyroidism. pHPT is typically caused by a solitary parathyroid adenoma, less frequently by multiple parathyroid gland disease (MGD) and rarely by parathyroid carcinoma. Secondary hyperparatyroidism (sHPT) is a common complication in patients with chronic renal failure. The aim of this study was to estimate sensitivity of dual tracer 99mTc-tetrofosmin and 99mTc-pertechnetate subtraction scintigraphy in detection of abnormal parathyroid glands in patients with pHPT and sHPT confirmed by histopathology. METHODS: In 46 patients, (77 abnormal parathyroid glands), 30 with pHPT and 16 with sHPT parathyroid scintigraphy was done preoperatively. All the patients had histopathological confirmation of diagnosis. Abnormal parathyroid glands weighted from 0.1 to 7 g. After iv injection dynamic scintigraphy during 25 minutes (one frame-one minute) using 555 MBq of 99mTc-tetrofosmin, and three hours latter using 111 MBq of 99mTc/pertechnetate was performed. 99mTc-tetrofosmin dynamic study was followed by static scintigraphy of the neck and chest 30 minutes, 1, 2 and 3 hours after iv injection. RESULTS: An abnormal scintigraphic finding was found in 44 of 46 patients with sensitivity of 96%. In pHPT sensitivity was 93% (28 of 30 patients, and 28 of 30 glands). In sHPT scintigraphy was abnormal in all the patients (sensitivity 100%). In the patients with sHPT scintigraphy detected 30 of 47 abnormal parathyroid glands (sensitivity 64%). An overall sensitivity of scintigraphy per gland, for pHPT and sHPT in detecting 58 of 77 abnormal parathyroid glands was 75%. CONCLUSION: An abnormal scintigraphic result per patient was found in 44 patients (sensitivity 96%) and 58 of 77 abnormal parathyroid glands were detected (sensitivity 750/0). A high sensitivity of dual tracer subtraction 99mTc-tetrofosmin/99mTc-pertechnetate parathyroid scintigraphy in detecting abnormal parathyroid glands in primary and secondary hyperparathyroidism was achieved.

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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.

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BACKGROUND/AIM: Beside many actual groups of classification criteria, uniform classification criteria for Sjögren's syndrome (SS) are still missing. The ophtalmic component of SS is well defined. Criteria for classifying its oral component remain controversial. The fifth item of the European Union and the United States of America (EU-US) revised diagnostic classification criteria in 2002, is an objective evidence of xerostomia, diagnosed by one of the tests: unstimulated whole sialometry (UWS), parotid sialography, and dynamic salivary gland scintigraphy (DSGS). The aim of this study was to evaluate senstitivity, specificity, positive and negative predictive value and accuracy of DSGS with ascorbic acid stimulation in detecting xerostomia in SS patients and to compare DSGS findings with UWS values. METHODS: Tests DSGS and UWS were done in 20 patients with SS and in 10 of the control subjects. The findings of DSGS were graded from 1 to 4 scintigraphie (SCT) grade 1--normal finding; SCT grade 2--moderate function damage; SCT grade 3--serious function damage, SCT grade 4--very serious function damage. UWS measured 1.5 hour after the breakfast lasted 15 minutes. UWS bellow 2.5 ml/15min min. considered pathological. RESULTS: All SS patients had pathological SCT findings. Comparing SCT grade between the patients and the control group, high statistical significance was found (p < 0.001). The estimated sensitivity of DSGS was 100%, specificity 80%, positive predictive value 91%, negative predictive value 100% and accuracy 93%. The calculated sensitivity of UWS was 75%. Salivary function damage detected by scintigraphy was in positive correlation with UWS findings. CONCLUSION: DSGS is a diagnostic test with high sensitivity, specificity, accuracy and positive and negative predictive values in detecting salivary function damage in SS patients. DSGS and UWS are very sensitive diagnostic tests for objective evidence of xerostomia, and have to be ones of the earliest investigations which shoud be performed in subjects suspected of SS. Test DSGS is more sensitive, and seems to better reflect symptoms of dry mouth than UWS.

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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.

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