Usefulness of 99mTc-methylene diphosphonate scintigraphy in nephrocalcinosis.

Abnormally increased uptake of 99mTc-methylene diphosphonate in the kidney parenchyma was found in a patient with acutely exacerbated sarcoidosis. The findings could be related to active sites of nephrocalcinosis.     

Myocardial infarct imaging with 99mTc-pyrophosphate and 99mTc-methylene diphosphonate: lack of correlation.

A prospective study of eight patients with recent transmural myocardial infarction was performed using 99mTc-Sn-pyrophosphate and 99mTc-Sn-methylene diphosphonate in each patient. All pyrophosphate scans were strongly positive whereas the diphosphonate scan was strongly positive in only one case. We conclude that 99mTc-Sn-pyrophosphate is preferable to 99mTc-Sn-methylene diphosphonate for myocardial imaging.     

99mTc-methylene diphosphonate imaging in neural crest tumors.

Thirteen patients with neural crest tumors were each studied with a radionuclide skeletal survey, a radiographic skeletal survey, and an iliac crest bone marrow aspiration. The RN skeletal survey proved to be more accurate that the radiographic skeletal survey in: 1) detecting the primary tumor; 2) demonstrating bony metastatic disease; and 3) evaluating response to therapy. The overall accuracy of the RN skeletal survey in detecting metastatic disease correlated with the results of bone marrow aspiration both in the initial detection of metastatic disease and the evaluation of response during therapy.     

Alendronate does not interfere with 99mTc-methylene diphosphonate bone scanning.

Several studies have found that administration of etidronate results in competitive interference with 99mTc-labeled bone scanning reagents. In contrast, in other studies this problem was not encountered with other bisphosphonates. METHODS: We prospectively studied 9 patients with hormone-refractory prostate cancer. 99mTc-methylene diphosphonate (MDP) bone scanning was performed before they received alendronate, and scanning was repeated a mean of 16.6 d afterward, when the patients had been receiving 40 mg alendronate daily for a mean of 6 d. In addition, 7 patients who underwent delayed scanning when they had been receiving alendronate for a mean of 111 d were also restudied. Quantitative whole-body bone scanning was performed, and radioactivity deposited in the bone metastasis was determined using region-of-interest analysis. RESULTS: A <6% increase in whole-body retention of 99mTc-MDP was seen on the initial postalendronate scan compared with the baseline scan. No significant differences in activity were seen in the bone lesion evaluated on the baseline and initial postalendronate studies. The delayed postalendronate scan generally showed similar or higher tracer accumulation compared with the baseline scan. CONCLUSION: Alendronate did not competitively inhibit uptake of 99mTc-MDP in the skeleton or tumor metastasis. Use of alendronate before bone scanning is unlikely to result in decreased detection of lesions or falsely decreased 99mTc-MDP activity at metastatic bone tumor sites.     

Accumulation of 99mTc-methylene diphosphonate in an adenocarcinoma of the lung.

Increased accumulation of 99mTc-methylene diphosphonate (MDP) was observed in an adenocarcinoma of the lung during the performance of routine bone imaging.     

Atlas of 99mTc-methylene diphosphonate renal images in pediatric oncology.

We describe the urinary tract abnormalities observed with bone scintigraphy during the evaluation of malignant disease. The possible abnormal renal patterns are discussed.     

Increased renal retention of 99mTc-methylene diphosphonate after nephron-sparing surgery.

Nephron-sparing surgery has become established as an effective treatment for localized renal cell carcinoma when preservation of renal function is necessary. The surgery usually requires temporary renal artery occlusion and may induce ischemic renal damage. In this study, we retrospectively evaluated renal activity on bone scintigraphy after nephron-sparing surgery. METHODS: Eleven patients who underwent nephron-sparing surgery for renal cell carcinoma and had a normal contralateral kidney were studied. A total of 12 bone scintigraphy images with 99mTc-labeled methylene diphosphonate were obtained within 1 y after surgery in these patients to assess skeletal metastasis. Activity in the spared renal parenchyma was compared visually with that in the contralateral normal kidney. RESULTS: The tumor was successfully resected in every patient, and no clinically significant complications occurred. Activity in the spared renal parenchyma was elevated in six of seven examinations performed within 21 d after surgery. In three examinations, the increase in renal activity was heterogeneous, being relatively prominent near the surgical margin. Increased renal activity was not observed on five examinations performed 3 mo or more after surgery. CONCLUSION: Renal retention of bone-seeking agents is elevated in the early period after nephron-sparing surgery, probably as a result of ischemic insult during the surgical procedure. Bone scintigraphy may aid in evaluating the presence and degree of ischemic damage of the spared renal parenchyma.     

Localization of 99mTc-methylene diphosphonate in skin lesions of pseudoxanthoma elasticum.

Increased uptake of 99mTc-methylene diphosphonate (MDP) is demonstrated in a patient with pseudoxanthoma elasticum (PXE) at the affected site. PXE is a hereditary disease with variable expression. Calification of dermal elastic fibers is a characteristic feature of affected skin. Recently, apatite crystals were identified in the affected skin of the patients with PXE. The mechanism of uptake of 99mTc-MDP is probably related to chemisorption of the tracer onto hydroxyapatite crystals in the affected dermis.     

Diagnostic value of 99mTc-methylene diphosphonate and 99mTc-pentavalent DMSA compared with 99mTc-sestamibi for palpable breast lesions.

Different radiopharmaceuticals have been used to detect breast cancer. Among them, sestamibi has been extensively studied and has come to have a well-recognized role in the evaluation of palpable breast lesions. The goal of this study was to compare the diagnostic value of 99mTc-labeled compounds, such as methylene diphosphonate (MDP) and pentavalent dimercaptosuccinic acid (DMSA-V), with sestamibi for palpable breast lesions, in the scope of a multicenter trial sponsored by the International Atomic Energy Agency. METHODS: Patients from 7 countries were included: 47 women (mean age, 54 +/- 13 y) examined with MDP and sestamibi and 111 women (mean age, 55 +/- 12 y) examined with DMSA-V and sestamibi. Cancer was diagnosed in 41 of 49 lesions from the MDP group and in 78 of 113 lesions from the DMSA-V group. Axillary lymph node involvement was observed in 18 of 30 patients from the first group and in 27 of 53 patients from the second group. Prone scintimammography was performed using a dose of 740 MBq of each tracer, and diagnostic values were calculated from a masked interpretation of scans. RESULTS: In the first group, the sensitivity for sestamibi and MDP studies was 82.9% and 65.9%, respectively, with a specificity of 87.5% and 50%, respectively. In the second group, the sensitivity for sestamibi and DMSA-V studies was 87.2% and 65.4%, respectively, with a specificity of 77.1% and 74.3%, respectively. Regarding axillary involvement, the sensitivity was 33.3% for sestamibi in both groups, whereas the values for MDP and DMSA-V were 16.7% and 7.4%, respectively. In contrast, the specificity for sestamibi was 83.3% and 92.3% for the first and second groups, respectively, and the specificity for MDP and DMSA-V was 91.7% and 100%, respectively. CONCLUSION: Sestamibi is the most adequate alternative among the mentioned 99mTc-labeled radiopharmaceuticals for the evaluation of palpable breast lesions.     

Uptake and localization of 99mTc-methylene diphosphonate in mouse osteosarcoma

The localization of 99mTc-methylene diphosphonate (99mTc-MDP) in mouse osteosarcoma was studied using a skeletal scintigraphic method and macro- and microautoradiographic methods. On the skeletal scintigraph, the tumor showed a high uptake of 99mTc-MDP and its concentration was about 20 times as high as the value seen in the muscular tissue. The macroautoradiography showed high activity in the tumor bone region and little activity in the nonossified region. On the microautoradiography, the activity of 99mTc-MDP was localized in the mineralized matrix of tumor bone and was almost nil in the nonmineralized matrix (osteoid) and the tumor cells. These findings indicate that the mineralization of the tumor bone matrix plays an important role in 99mTc-MDP uptake in osteosarcoma.     

Uptake and localization of99mTc-methylene diphosphonate in mouse osteosarcoma

The localization of^99mTc-methylene diphosphonate (^99mTc-MDP) in mouse osteosarcoma was studied using a skeletal scintigraphic method and macro- and microautoradiographic methods. On the skeletal scintigraph, the tumor showed a high uptake of^99mTc-DMP and its concentration was about 20 times as high as the value seen in the muscular tissue. The macroautoradiography showed high activity in the tumor bone region and little activity in the nonossified region. On the microautoradiography, the activity of^99mTc-MDP was localized in the mineralized matrix of tumor bone and was almost nil in the nonmineralized matrix (osteoid) and the tumor cells. These findings indicate that the mineralization of the tumor bone matrix plays an important role in^99mTc-MDP uptake in osteosarcoma.     

Unintentional human skeletal imaging with99mTc-methylene diphosphonate 45 months beyond expiration

Eight patients were inadvertently administered, and imaged with, 99mTc-labeled MDP which was 45 months expired. Two cases are presented. All patients were subsequently imaged with normal MDP. The images obtained with expired MDP were clinically acceptable. No differences in scan abnormalities were observed compared with normal MDP for any of the patients. None of the patients suffered any side effects attributable to the expired MDP.     

Clinical value of planar and tomographic dual-isotope scintigraphy using 99mTc-methylene diphosphonate and 131I in patients with thyroid cancer

PURPOSE: (131)I whole-body scintigraphy is a highly sensitive method for the detection of differentiated thyroid tumours and metastases. However, a lack of anatomical landmarks and the physiological excretion of the tracer complicates the evaluation of the images. Therefore, we determined whether additional bone scintigraphy in combination with (131)I scintigraphy, simultaneously acquired via planar and tomographic techniques, positively contributes to the treatment plan in patients with non-conclusive (131)I images. METHODS: Twenty-one patients with differentiated thyroid cancer and known metastases or unclear findings in the (131)I whole-body scan underwent dual-isotope scintigraphy (DIS) within 2-7 days after application of 5000-8000 MBq (131)I. Dual-energy planar and tomographic data were acquired simultaneously and the results compared with other imaging modalities. RESULTS: In 48% of the cases (10 of 21), DIS supplied important additional information that either altered the treatment plan or staging of the patients. In 28% (six of 21), DIS provided new information that was not known before, but did not change the staging of the patients. In five cases (24%), DIS did not add any new data regarding the extent of the disease. CONCLUSIONS: The simultaneous acquisition of (131)I and (99m)Tc-methylene diphosphonate provides clear landmarks and facilitates the localization of functioning metastases from differentiated thyroid cancer as well as improves the fusion with morphological images. It can be performed easily and also transferred to other isotope combinations.