Exercise-induced muscle uptake of technetium-99m MDP

Intense muscle localization of Tc-99m MDP to upper extremity musculature was noted three days following weight lifting exercises. This phenomenon is due to an unknown mechanism although several causative factors have been suggested.     

Accumulation of technetium-99m MDP in an intramuscular hemangioma

The accumulation of a bone-seeking radiopharmaceutical on delayed imaging in a hemangioma has not been described previously. The variable scintigraphic findings of hemangiomas are described in detail.     

Soft-tissue uptake of technetium-99m MDP in multiple myeloma

Abnormal accumulation of Tc-99m MDP in the lungs and stomach was observed in a patient with multiple myeloma and refractory hypercalcemia. There was no roentgenographic evidence of calcification. At postmortem examination, the presence of amyloid deposits was confirmed in both organs, while the corresponding metastatic calcification was demonstrated only in the gastric mucosa. It seems likely that, in our case, soft-tissue localization of bone-seeking agent was attributable to the presence of amyloid deposits rather than metastatic calcification. No cases showing the combined occurrence of amyloid deposition and metastatic calcification in soft-tissues have previously been demonstrated to concentrate bone-seeking agent.     

Dermal uptake of technetium-99m MDP in calcinosis cutis

A rare case of extensive dermal uptake of Tc-99m MDP associated with renal failure is reported. The mechanism of Tc-99m MDP uptake in such examples of metastatic calcification is not proved, but may relate to adsorption onto hydroxyapatite crystals. This phenomenon is useful in demonstrating distribution of nonvisceral metastatic calcification.     

Cardiac calcification causing arrhythmia detected by technetium-99m MDP and SPECT

SPECT was used to identify a focal accumulation of cardiac calcification using Tc-99m MDP in a patient with an arrhythmia and known metastatic calcification elsewhere.     

Extraosseous localization of technetium-99m MDP in benign cystic teratoma

Two cases of primary retroperitoneal benign teratoma, in which Tc-99m MDP localized in the primary tumor are presented. Localization of bone-imaging agents in neuroblastoma has been reported but, extraosseous localization of bone-imaging agents in teratomas has not been confirmed.     

Gallbladder visualization on a technetium-99m MDP bone scan

A bone scan performed on a 54-year-old woman with metastatic breast carcinoma and concurrent cholelithiasis demonstrated intense gallbladder concentration of radionuclide.     

Technetium-99m APD compared with technetium-99m MDP as a bone scanning agent

We have investigated the possibilities of technetium-99m-(-3-aminohydroxypropylidene)-1-1-bisphosphon ate ([99mTc]APD) as a bone scanning agent in 14 normal subjects and 28 patients. Similar studies in the same normal subjects and patients were carried out with 99mTc-methylene-bisphosphonate ([99mTc]MDP). The compounds were labeled with 99mTc by means of an electrolytical method; the free pertechnetate content was always under 1%. The [99mTc]APD T1/2 of the third component of the disappearance plasma curve in six normal subjects was 152 +/- 46 min (mean +/- s.d.), while the 24-hr whole-body retention (WBR) was 17.6% +/- 4.6. The [99mTc]MDP value of the 24-hr WBR was 28.6% +/- 3.9 (p less than 0.001). The bone/soft-tissue ratio (B/ST) was investigated in eight control subjects on the eleventh thoracic and the fourth lumbar vertebrae. The B/ST ratios were similar for both APD and MDP studies. In 28 patients with suspected bone metastasis or primary bone disease, bone scintigraphy was carried out; both compounds showed similar findings and the same number of positive results. In five of these patients, the lesion/normal bone ratio was determined with values of 4.6 +/- 2.0 in APD studies and 4.8 +/- 2.3 with MDP. APD was also used in 126 patients; no adverse reactions were observed. The APD dose used i.v. for bone scanning was 200-fold less than those employed by mouth per day, for the treatment of bone disease for long periods. In our experience, APD appears to be an adequate agent for bone scintigraphy.     

Extraosseous uptake of technetium-99m MDP in secondary deposits of neuroblastoma

Extraosseous uptake of radiophosphate compounds i well recognized in primary neural crest tumors. In a review of 32 cases of neuroblastoma presenting over a three-year period at Children's Hospital of Philadelphia, nine patients were noted to have secondary lesions in eleven different sites accumulating radiotracer. The extraosseous uptake in metastases included: ascites, liver, lung, anterior mediastinum, and posterior mediastinum. These cases are reported to emphasize the ability of bone imaging to detect the presence of extraosseous soft tissue metastases and primary lesions.     

Visualization of soft tissue by technetium-99m MDP in polymyositis. Case reports

Two patients with polymyositis showed abnormal muscular uptake of Tc-99m-methylene diphosphonate (MDP) during routine bone imaging. Imaging with Tc-99m MDP is a useful tool in monitoring the activity of the diseased muscle.     

Multifocal pyomyositis. Diagnosis on technetium-99m MDP bone scan

Pyomyositis is a bacterial infection of skeletal muscle occurring in the absence of trauma or a primary site of infection. The condition is rare in temperate climates. The diagnosis is often difficult to make and frequently delayed since the suppurative process is confined by the tense overlying muscle and fascia. The bone scan is very useful in differentiating underlying osteomyelitis and septic arthritis. An 11-year-old boy is described who presented with multifocal pyomyositis in the elbow region and thigh. Lateral blood pool images suggested infection with liquefaction within the muscles without evidence of osteomyelitis.     

Diagnosis of discitis by SPECT technetium-99m MDP scintigram. A case report

A 29-year-old male presented with a two month history of intermittent low back pain following a febrile illness. Two planar bone scans performed with Tc-99m MDP were normal despite roentgenographic and SPECT scintigraphic evidence of discitis. This case demonstrates the increased sensitivity of SPECT in the diagnosis of discitis.     

Accumulation of technetium-99m MDP in a cavernous hemangioma of the liver

A cavernous hemangioma of the liver presented as an area of increased activity on an isotope bone scan. A review of the literature fails to reveal any previous reports of this phenomenon.     

Technetium-99m MDP vs technetium-99m dicarboxypropane diphosphonate. A clinical comparison in various pathologic conditions

The performance of Tc-99m MDP vs Tc-99m dicarboxypropane diphosphonate (DPD) was evaluated in 20 patients with various skeletal bone diseases. Each patient was investigated twice, with an interval of three days between studies and using the same protocol, hence each case served as its own control. The results were: In a subjective interpretation by five independent and experienced investigators, the difference between agents was small, yet in favor of MDP. Region of interest (ROI) analysis of the pooled results in 74.4% of all cases shows a higher bone lesion to normal bone ratio (BL/NB), and in 79.3% of all cases, a better bone lesion to soft tissue ratio (BL/ST) with Tc-99m MDP. When considering pathology types separately, the BL/NB ratio of Tc-99m MDP was 17.7% higher than the one of Tc-99m DPD in metastases, 9.5% higher in rheumatoid arthritis, 2.8% higher in metabolic diseases, and 24% higher in bone fractures. Student's paired t test on the pooled BL/NB ratios shows a difference of 15.5% for Tc-99m MDP, significant at P = 0.00155. The overall results of our study favor Tc-99m MDP.     

Intracranial Tc99m MDP uptake in Sturge-Weber syndrome

A case of intracranial extraosseous 99mTc MDP uptake is presented, which was found on CT to be due to dystrophic gyral calcification characteristic of Sturge-Weber syndrome (SWS). The imaging characteristics of SWS are described. The possibility of extraosseous MDP uptake should be considered when unusual or atypical 'hot spots' are seen on bone scanning.