-
[show abstract]
[hide abstract]
ABSTRACT: Bone scintigraphy (BS) has been used extensively for many years for the diagnosis of bone metastases despite its low specificity and significant rate of equivocal lesions. (18)F-Fluoride PET/CT has been proven to have a high sensitivity and specificity in the detection of malignant bone lesions, but its effectiveness in patients with inconclusive lesions on BS is not well documented. This study evaluated the ability of (18)F-fluoride PET/CT to exclude bone metastases in patients with various malignant primary tumours and nonspecific findings on BS.
We prospectively studied 42 patients (34-88 years of age, 26 women) with different types of tumour. All patients had BS performed for staging or restaging purposes but with inconclusive findings. All patients underwent (18)F-fluoride PET/CT. All abnormalities identified on BS images were visually compared with their appearance on the PET/CT images.
All the 96 inconclusive lesions found on BS images of the 42 patients were identified on PET/CT images. (18)F-Fluoride PET/CT correctly excluded bone metastases in 23 patients (68 lesions). Of 19 patients (28 lesions) classified by PET/CT as having metastases, 3 (5 lesions) were finally classified as free of bone metastases on follow-up. The sensitivity, specificity, and positive and negative predictive values of (18)F-fluoride PET/CT were, respectively, 100 %, 88 %, 84 % and 100 % for the identification of patients with metastases (patient analysis) and 100 %, 82 % and 100 % for the identification of metastatic lesions (lesion analysis).
The factors that make BS inconclusive do not affect (18)F-fluoride PET/CT which shows a high sensitivity and negative predictive value for excluding bone metastases even in patients with inconclusive conventional BS.
European Journal of Nuclear Medicine 08/2012; 39(11):1730-6. · 4.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the utility of diuretic dynamic renal scintigraphy (DDRS) with technetium-99m-L,L-ethylenedicysteine ((99m)Tc-EC) in patients with indeterminate or possible false-positive results for urinary obstruction by technetium-99m diethylenetriamine penta-acetic acid ((99m)Tc-DTPA) DDRS.
A total of 92 patients (63 male; mean age, 16.6 +/- 21.25 years) were studied, with a total of 103 kidneys presenting indeterminate (20/103) or possible false-positive results for obstruction attributable to reduced renal function or severe kidney dilation (83/103) by (99m)Tc-DTPA DDRS (<60% of radiopharmaceutical excreted in 20 minutes-half-time clearance [T(1/2)] >15 minutes). Patients were reimaged after intravenous injection of (99m)Tc-EC, with dynamic images before and after furosemide administration using the same acquisition parameters applied in the previous (99m)Tc-DTPA study. Time interval between (99m)Tc-DTPA and (99m)Tc-EC renograms was 2-64 days. The percentage of excreted material 20 minutes after furosemide was calculated using both radiopharmaceuticals, and were statistically compared using the paired samples t test.
The excretion after furosemide injection was 25.3% +/- 18.2% for (99m)Tc-DTPA and 41.2% +/- 26.1% for (99m)Tc-EC, with a statistically significant difference between both radiopharmaceuticals (P <.0001). Using (99m)Tc-EC obstruction was excluded in 36 of 103 kidneys, which excreted >60%. A total of 10 of 83 kidneys (12.0%) with an obstructive pattern by (99m)Tc-DTPA study turned out to be indeterminate by (99m)Tc-EC DDRS. There was an agreement between (99m)Tc-EC and (99m)Tc-DTPA studies in 54 of 83 kidneys with obstructive (65.1%) and in 3 of 20 (15.0%) with indeterminate patterns.
(99m)Tc-EC was more effective than (99m)Tc-DTPA for excluding obstruction, presenting less false-positive and indeterminate results. (99m)Tc-EC can substitute (99m)Tc-DTPA to evaluate patients with urinary tract dilation.
Urology 03/2010; 76(2):283-8. · 2.43 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Creatinine clearance has been reported to be inaccurate for the estimation of glomerular filtration rate (GFR) in patients with sickle cell anaemia (SCA). Inulin clearance, the reference method for GFR estimation, is impractical for routine use in these patients, and 51Cr-EDTA measurements of the GFR have been rarely reported in this disease.
In order to obtain reference 51Cr-EDTA values in this disease, we studied 70 patients (40 females; 13-59 years of age, mean: 31.6 years) with homozygous SCA, normal serum creatinine and urinary albumin excretion < or =200 microg x min(-1). All patients were submitted to single-injection 51Cr-EDTA GFR, urinary albumin and haematocrit measurements. 51Cr-EDTA clearances were calculated in different age groups (<20, 20-29, 30-39, 40-49 and >50 years).
The mean GFR (+/-standard deviation) obtained for the 70 patients was 111.5+/-23.1 ml x min(-1). Analysis of variance for evaluation of the possible interaction effect between 51Cr-EDTA clearance and sex, age, urinary albumin and haematocrit demonstrated patient age as the only factor influencing 51Cr-EDTA clearance (P < 0.001). The Spearman correlation coefficient showed a significant relationship between 51Cr-EDTA clearance and patient age (r = -0.44, P = 0.0001), but not between 51Cr-EDTA and urinary albumin (r = -0.17, P = 0.1546) or haematocrit (r = 0.079, P = 0.5121). The group aged 20-29 years presented the highest 51Cr-EDTA clearance mean value (126.7+/-20.4 ml x min(-1)), with a progressive reduction in the older groups.
Young adults with homozygous SCA, normal serum creatinine and micro-albuminuria or normo-albuminuria present supranormal 51Cr-EDTA GFR values. These values rapidly decrease after 30 years of age. We did not find association between urinary albumin and GFR in these patients.
Nuclear Medicine Communications 01/2007; 27(12):959-62. · 1.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Background: Creatinine clearance has been reported to be inaccurate for the estimation of glomerular filtration rate (GFR) in patients with sickle cell anaemia (SCA). Inulin clearance, the reference method for GFR estimation, is impractical for routine use in these patients, and 51Cr-EDTA measurements of the GFR have been rarely reported in this disease.
Methods: In order to obtain reference 51Cr-EDTA values in this disease, we studied 70 patients (40 females; 13-59 years of age, mean: 31.6 years) with homozygous SCA, normal serum creatinine and urinary albumin excretion <or=200 μg·min-1. All patients were submitted to single-injection 51Cr-EDTA GFR, urinary albumin and haematocrit measurements. 51Cr-EDTA clearances were calculated in different age groups (<20, 20-29, 30-39, 40-49 and>50 years).
Results: The mean GFR (±standard deviation) obtained for the 70 patients was 111.5±23.1 ml·min-1. Analysis of variance for evaluation of the possible interaction effect between 51Cr-EDTA clearance and sex, age, urinary albumin and haematocrit demonstrated patient age as the only factor influencing 51Cr-EDTA clearance (P<0.001). The Spearman correlation coefficient showed a significant relationship between 51Cr-EDTA clearance and patient age (r=-0.44, P=0.0001), but not between 51Cr-EDTA and urinary albumin (r=-0.17, P=0.1546) or haematocrit (r=0.079, P=0.5121). The group aged 20-29 years presented the highest 51Cr-EDTA clearance mean value (126.7±20.4 ml·min-1), with a progressive reduction in the older groups.
Conclusion: Young adults with homozygous SCA, normal serum creatinine and micro-albuminuria or normo-albuminuria present supranormal 51Cr-EDTA GFR values. These values rapidly decrease after 30 years of age. We did not find association between urinary albumin and GFR in these patients.
Nuclear Medicine Communications 11/2006; 27(12):959-962. · 1.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The assessment of the functional status of the salivary glands has been used in the scintigraphic evaluation of xerostomia. Several quantitative methods derived from standard dynamic scintigraphy have been suggested. However, the indices proposed are quite variable and unlikely to be useful in clinical practice. The objectives of this study were to obtain reference values of major salivary glands uptake and excretion fraction in healthy subjects and to obtain normal ratios of Tc-pertechnetate uptake by the major salivary glands in comparison to the thyroid gland uptake. The standardization of these values has the purpose of making this evaluation faster and more objective. Fifty volunteers without clinical evidence of xerostomia or thyroid disease underwent static salivary glands scintigraphy with Tc-pertechnetate. Static images were obtained at 20 minutes and then at 3 minutes after oral stimulation with lemon juice. Percent uptake, excretion fraction and salivary gland to thyroid ratio rates were calculated for the parotid and the submandibular glands. The mean of the uptake values at 20 minutes for the right and left parotid glands were respectively 0.31% and 0.26%, and for the submandibular glands 0.15%. The excretion fraction of the tracer after the lemon juice stimulation was 70% for the parotids glands, 50% for the right and 49% for the left submandibular glands. The mean+/-SD salivary gland to thyroid count ratio was 0.79+/-0.45 for the right parotid, 0.78+/-0.5 for the left parotid, 0.67+/-0.33 and 0.66+/-0.34 for the right and left submandibular glands, respectively. Salivary glands scintigraphy with uptake and excretion fraction calculation is an easy to perform, non-invasive and objective method to investigate salivary glands function. These findings help the nuclear physician to interpret salivary gland scintigraphy more objectively, even in patients with thyroid gland dysfunction in whom Tc-pertechnetate thyroid uptake may be abnormal.
Nuclear Medicine Communications 05/2006; 27(4):395-403. · 1.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The assessment of the functional status of the salivary glands has been used in the scintigraphic evaluation of xerostomia. Several quantitative methods derived from standard dynamic scintigraphy have been suggested. However, the indices proposed are quite variable and unlikely to be useful in clinical practice.
The objectives of this study were to obtain reference values of major salivary glands uptake and excretion fraction in healthy subjects and to obtain normal ratios of 99mTc-pertechnetate uptake by the major salivary glands in comparison to the thyroid gland uptake. The standardization of these values has the purpose of making this evaluation faster and more objective.
Fifty volunteers without clinical evidence of xerostomia or thyroid disease underwent static salivary glands scintigraphy with 99mTc-pertechnetate. Static images were obtained at 20 minutes and then at 3 minutes after oral stimulation with lemon juice. Percent uptake, excretion fraction and salivary gland to thyroid ratio rates were calculated for the parotid and the submandibular glands.
The mean of the uptake values at 20 minutes for the right and left parotid glands were respectively 0.31% and 0.26%, and for the submandibular glands 0.15%. The excretion fraction of the tracer after the lemon juice stimulation was 70% for the parotids glands, 50% for the right and 49% for the left submandibular glands. The mean±SD salivary gland to thyroid count ratio was 0.79±0.45 for the right parotid, 0.78±0.5 for the left parotid, 0.67±0.33 and 0.66±0.34 for the right and left submandibular glands, respectively.
Salivary glands scintigraphy with uptake and excretion fraction calculation is an easy to perform, non-invasive and objective method to investigate salivary glands function. These findings help the nuclear physician to interpret salivary gland scintigraphy more objectively, even in patients with thyroid gland dysfunction in whom 99mTc-pertechnetate thyroid uptake may be abnormal
Nuclear Medicine Communications 03/2006; 27(4):395-403. · 1.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Several factors may interfere with the success rate of radioiodine therapy (RIT) in Graves' disease. Our aim was to evaluate, retrospectively, some of these factors in the outcome of RIT.
Patient gender, age at diagnosis, ophthalmopathy, disease duration, thyroid size, drug used as clinical treatment, thionamide withdrawal period during RIT preparation, FT4, TSH and [99mTc]pertechnetate thyroid uptake prior to RIT were studied as potential interference factors for RIT success. Eighty-two Graves' disease patients were submitted to RIT after thionamide treatment failure. Prior to RIT, 67 patients were receiving methimazole and 15 propylthiouracil. Thirty-three patients received thionamides during RIT; in 49 patients the medication was withdrawn for 2-30 days. [99mTc]pertechnetate thyroid uptake was determined before RIT. Fixed doses of 370 MBq of [131I]iodide were administered to all patients.
Eleven patients became euthyroid; 40 became hypothyroid and 31 remained hyperthyroid. There was no association between outcome and age at diagnosis, gender, ophthalmopathy, pre-RIT FT4, TSH, antithyroid antibodies or thyrostatic drug. Multiple logistic regression showed higher probability of treatment success in patients with thyroid mass <53 g (odds ratio (OR)=8.9), with pre-RIT thyroid uptake <12.5% (OR=4.1) and in patients who withdrew thionamide before RIT (OR=4.9).
Fixed doses of 370 MBq of radioiodine seem to be practical and effective for treating Graves' disease patients with [99mTc]pertechnetate uptake <12.5% and thyroid mass <53 g. This treatment is clearly not recommended for patients with large goitre. In contrast to what could be expected, patients with a high pre-RIT thyroid uptake presented a higher rate of RIT failure.
Nuclear Medicine Communications 11/2005; 26(11):957-63. · 1.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Background and objective: Several factors may interfere with the success rate of radioiodine therapy (RIT) in Graves' disease. Our aim was to evaluate, retrospectively, some of these factors in the outcome of RIT.
Methods: Patient gender, age at diagnosis, ophthalmopathy, disease duration, thyroid size, drug used as clinical treatment, thionamide withdrawal period during RIT preparation, FT4, TSH and [99mTc]pertechnetate thyroid uptake prior to RIT were studied as potential interference factors for RIT success. Eighty-two Graves' disease patients were submitted to RIT after thionamide treatment failure. Prior to RIT, 67 patients were receiving methimazole and 15 propylthiouracil. Thirty-three patients received thionamides during RIT; in 49 patients the medication was withdrawn for 2-30 days. [99mTc]pertechnetate thyroid uptake was determined before RIT. Fixed doses of 370 MBq of [131I]iodide were administered to all patients.
Results: Eleven patients became euthyroid; 40 became hypothyroid and 31 remained hyperthyroid. There was no association between outcome and age at diagnosis, gender, ophthalmopathy, pre-RIT FT4, TSH, antithyroid antibodies or thyrostatic drug. Multiple logistic regression showed higher probability of treatment success in patients with thyroid mass <53 g (odds ratio (OR)=8.9), with pre-RIT thyroid uptake <12.5% (OR=4.1) and in patients who withdrew thionamide before RIT (OR=4.9).
Conclusions: Fixed doses of 370 MBq of radioiodine seem to be practical and effective for treating Graves' disease patients with [99mTc]pertechnetate uptake <12.5% and thyroid mass <53 g. This treatment is clearly not recommended for patients with large goitre. In contrast to what could be expected, patients with a high pre-RIT thyroid uptake presented a higher rate of RIT failure.
Nuclear Medicine Communications 10/2005; 26(11):957-963. · 1.40 Impact Factor
-
Elba C.S.C. Etchebehere,
Mauro Caron,
Juliana A. Pereira, Mariana C.L. Lima,
Allan O. Santos,
Celso D. Ramos,
Fabiana B. Barros,
Adelina Sanches,
Rogério Santos-Jesus,
Willian Belangero,
Edwaldo E. Camargo
[show abstract]
[hide abstract]
ABSTRACT: Children with an uncomplicated femoral fracture, treated with superimposition of fragments and intentional shortening, usually develop overgrowth of the fractured femur and the ipsilateral tibia which may compensate for the initial shortening and enable the limb in question to reach a length similar to that on the normal side. The overgrowth is evaluated clinically and by scanography. The increased metabolic activity of the growth plates that support this overgrowth has not been documented by any laboratory method. In order to evaluate the metabolic activity of the growth plates, 18 patients (11 males, seven females; mean age 6.1 years) with fractures of the femur were studied at three different time intervals (2-5 months, 6-12 months and 18-24 months). Three-phase bone scintigraphy was performed in all patients. Ten children (five males, five females; mean age 7.5 years) who had had bone imaging for other reasons were used as the control group. Visual analysis of the flow and equilibrium phases was performed for the distal femoral and proximal tibial growth plates. Visual and semi-quantitative analyses of the delayed images were performed for the distal femoral and proximal and distal tibial growth plates. Semi-quantitative analyses yielded the following activity ratios: (a) the distal femoral growth plate of the fractured femur to the contralateral one (FR); (b) the proximal growth plate of the tibia on the side of the fractured femur to the contralateral one (TpR); (c) the distal growth plate of the tibia on the side of the fractured femur to the contralateral one (TdR); and (d) in the control group, the distal growth plates of both femora (FCG) and the proximal (TCGp) and distal (TCGd) growth plates of the tibiae. Visual analysis of the blood flow, equilibrium and delayed images showed increased activity in the distal femoral growth plates during the first and second time intervals, but not during the third. No significant activity changes were found in the proximal and distal tibial growth plates during any of the phases analysed. The mean and standard deviation for FR in the three time intervals were: FRI=1.22ǂ.27, FRII=1.17ǂ.16 and FRIII=1.09ǂ.20. FR values were significantly higher than in the control group (FCG=0.99ǂ.03) (P=0.033). The mean and standard deviation for TpR in the three time intervals were: TpRI=1.08ǂ.18, TpRII=0.94ǂ.09 and TpRIII=0.96ǂ.20. TpR values were not significantly different from those in the control group (TCGp=1.00ǂ.05). However, TpRI was significantly higher than TpRII (P=0.043). The mean and standard deviation for TdR in the three time intervals were: TdRI=1.10ǂ.41, TdRII=1.05ǂ.15 and TdRIII=1.13ǂ.36. TdR values were not significantly higher than in the control group (TCGd=1.00ǂ.04) (P=0.777). These results support the concept that three-phase bone imaging is able to quantify and determine that activation occurs in the distal femoral and proximal tibial growth plates of fractured femora. This phenomenon may explain the overgrowth observed in this injured bone structure.
European journal of nuclear medicine and molecular imaging 12/2000; 28(1):72-80. · 4.99 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Renal scintigraphy has been used for many years in the evaluation of renal transplants and can help in the diagnosis of graft complications, leading to prompt clinical management and preventing further deterioration of renal function. The purpose of this study was to evaluate the overall accuracy of renal scintigraphy with (99m)Tc-DTPA in the diagnosis of acute renal graft complications.
Seventy-six scintigraphic studies performed in 55 patients (ages ranging from 6 to 65 years), were reviewed. Scintigraphy results were compared to biopsies performed within 5 days of imaging. (99m)Tc-DTPA study was performed within a mean time of 19 days after kidney transplants. Dynamic images were performed in the anterior position of the abdomen and pelvis every 2 seconds for 80 seconds (flow phase) and every 15 seconds for 30 minutes (functional phase), after an intravenous injection of 370 MBq (10 mCi) of (99m)Tc-DTPA.
The scintigraphic results were concordant with the biopsies in 86% of the cases studied. The sensitivities of renal scintigraphy for detection of acute tubular necrosis (ATN), acute rejection (AR) and cortical necrosis (CN) were 98%, 87% and 100%, respectively. Specificities and accuracies for detection of ATN, AR and CN were 89%, 86% and 100%, and 95%, 87% and 100%, respectively.
Renal scintigraphy with (99m)Tc-DTPA showed a good overall accuracy in the detection of acute renal graft complications. It can be used as a reliable tool in the routine evaluation of these patients.
International braz j urol 29(6):507-16. · 1.07 Impact Factor
