99mTc-methylene diphosphonate and 67Ga-uptake in myositis ossificans

A histologically proven case of myositis ossificans is presented. Both 99mTc-MDP and 67Ga imaging demonstrated extensive uptake of radiotracers in the lesion.     

99mTc-methylene diphosphonate uptake by ossifications and calcifications of non-osseous metastatic tumors

Two cases of extra-osseous uptake of ^99mTc-methylene diphosphonate (MDP) by non-osseous metastatic tumors are reported. One was a metastasis with ossification in the abdominal wall from carcinoma of the sigmoid colon and the other was a metastasis with calcification from an ovarian carcinoma. The mechanism of extra-osseous uptake of ^99mTc-MDP is discussed. Bone scintigraphy can be a potential means to assess tumor spread with ossifications and calcifications.     

Influence of whole-body vibration on biodistribution of the radiopharmaceutical [99mTc]methylene diphosphonate in Wistar rats

Abstract

Purpose: The radionuclide bone scan is the basis of skeletal nuclear medicine imaging. Bone scintigraphy is a highly sensitive method for indicating disease in bone. Mechanical stimulation in the manner of whole-body vibration (WBV) appears beneficial to the maintenance and/or enhancement of skeletal mass in individuals. The aim of this work was to evaluate the effect of WBV on the biodistribution of the radiopharmaceutical [^99mTc]methylene diphosphonate (^99mTc-MDP ) in Wistar rats.

Materials and methods: In the biodistribution analysis, animals were anesthetized with sodium thiopental, the radiopharmaceutical ^99mTc-MDP was administered via ocular plexus and after 10 min the animals were submitted to vibration of 20 Hz (1 min) in an oscillatory platform. Following, the animals were sacrificed, the organs were isolated, the radioactivity determined in a well counter, and the percentages of radioactivity per gram (%ATI/g) in the organs were calculated. An unpaired t-test following Welch test (p < 0.05) was done for statistical analysis of the results.

Results: The biodistribution was significantly (p < 0.05) decreased in kidney, bone, lung, stomach, prostate and bowel.

Conclusion: The analysis of the results indicates that the vibration could produce metabolic alterations with influence in the uptake of the radiopharmaceutical ^99mTc-MDP in bone, stomach, bowel, prostate, kidney and bladder.     

Better visualization of a lung tumour with 99mTc-DPD than with 99mTc-glucoheptonate or 67Ga-citrate

A case of a squamous cell lung carcinoma detected with ^99mTc-DPD, ⁶⁷Ga-citrate and ^99mTc-glucoheptonate (GH) is reported. The highest uptake was seen with DPD and the lowest with ⁶⁷Ga. Emission-computed tomography was very useful in DPD imaging but gave less new information in GH and ⁶⁷Ga studies in comparison to traditional planar imaging. The patient had been given both irradiation and chemotherapy, which might be the cause of good accumulation of DPD and rather poor accumulation of GH and ⁶⁷Ga.     

骨化性肌炎的临床和MRI表现分析

目的:分析骨化性肌炎的临床和MRI表现特点,以提高其诊断和鉴别诊断的能力。方法:对16例经手术或穿刺病理证实为骨化性肌炎患者的临床和MR检查图像进行回顾性分析。结果:外伤后四肢痛性软组织肿块是其主要临床表现,T2WI上见有团块和分叶状不均匀信号、边缘有低信号带形成的软组织肿块,周围有显著的水肿带是其特征性的MRI表现。结论:骨化性肌炎临床上多有外伤史,MRI表现具有一定的特征性,提高对其MR表现的认识有助于诊断和鉴别诊断,避免不必要的手术。     

局限性骨化性肌炎的X线、CT表现

目的：探讨局限性骨化性肌炎的X线平片和CT表现,提高影像诊断水平。方法：回顾性分析19例经病理或随访证实局限性骨化性肌炎患者的X线、CT表现,其中19例均行X线平片检查,13例行CT检查。结果：X线表现为软组织内条片状或分层状骨化影;CT表现：早期（急性水肿期）局部肌肉水肿,无明确骨化成分,受累骨可出现轻微骨膜增生,中期（增殖肿块期）表现为分层状＂蛋壳＂样骨化,病灶中心呈软组织密度,晚期（骨化修复期）病灶局限,边界清楚,周围肌肉水肿消失,影像学表现为离心性分布的骨化团块。结论：局限性骨化性肌炎早期影像学表现缺乏特征性,容易误诊,中晚期分层状＂蛋壳＂样骨化对本病诊断有重要价值。     

A micro-autoradiographical study of the localization of 99mTc(Sn)-MDP and 99mTc-MDP in undecalcified bone sections

The localization of ^99mTc(Sn)-MDP in bone tissue was compared with ^99mTc-MDP by means of microautoradiography of undecalcified bone sections. Sections of good histological quality were obtained by a rapid embedding method in methylmethacrylate. No differences were found in the localization of these radiopharmaceuticals in fetal rat calvariae after incubation in vitro or in rat femora after administration in vivo. In the incubation experiment, hydrolyzed ^99mTc was formed. The uptake was high in areas of new bone formation. No uptake was seen in cells or in resorbing areas. In compact bone ^99mTc(Sn)-MDP was predominantly taken up in the vicinity of blood vessels.     

Ultrasound appearance of myositis ossificans

Ultrasonic evaluation of a soft tissue mass of the thigh was performed and suggested the diagnosis of myositis ossificans. Correlation with routine radiographic studies is made, as well as with the follow-up radiographic examination.     

The complementary role of sequential 99mTc-MDP and 67Ga-citrate scanning in the diagnosis and follow-up of neuroblastoma

Fourteen children with histopathologically confirmed neuroblastoma underwent 38 studies using ^99mTc-methylene-diphosphonate (MDP) and galliumcitrate Ga67 whole-body scintigraphy during various stages of the disease. Ten patients (71%) showed ^99mTc-MDP accumulation in the primary tumoral site, whereas 11 patients (78.6%) showed ⁶⁷Ga concentration. In 12 patients (86%), at least one of these two radiopharmaceuticals concentrated in the primary tumor. Nine patients had osseous or extraosseous metastases. All of these metastases (100%) were positive on ^99mTc-MDP sctintigraphy. No ⁶⁷Ga-citrate uptake was demonstrable in osseous metastases; only one extraosseous lung metastasis concentrated this radiopharmaceutical. ⁶⁷Ga-citrate was superior to ^99mTc-MDP with regard to accurately demonstrating the extent of primary tumors. Only ^99mTc-MDP indicated the relationship of the tumor to the kidneys and neighbouring osseous structures, prividing early screening of kidney compression and possible damage caused by the tumor. From these results, we found these two methods to be complementary for the diagnosis and follow-up of neuroblastoma; their combined use resulted in high diagnostic accuracy and a considerable gain of information. We therefore recommend sequential ^99mTc-MDP and ⁶⁷Ga-citrate scans for the diagnosis and evaluation of the primary tumor; periodic ^99mTc-MDP wholebody scans should be used in the follow-up of treatment, and for discovering disease exacerbations and metastases.Presented in part in the European Congress of Nuclear Medicine, London, England, September 1985     

Comparison of delayed hepatobiliary imaging using 99mTc-Sn-N-pyridoxyl-5-methyltryptophan and 67Ga-citrate imaging for diagnosis of hepatocellular carcinoma

Images were obtained both with a biliary agent, ^99mTc-Sn-N-pyridoxyl-5-methyltryptophan (^99mTc-PMT), and with ⁶⁷Ga-citrate in 40 cases of hepatocellular carcinoma and in 43 cases of other hepatic diseases and results were compared. Positive results were obtained by delayed ^99mTc-PMT imaging in 25 (63%) of 40 cases of hepatoma: the hepatic tumor showed increased uptake in 18 cases (45%) and equilibrated uptake in 7 cases (18%). Positive ⁶⁷Ga-citrate imaging was found in 28 (70%) of the 40 cases of hepatoma: increased uptake was seen in 24 cases (60%) and equilibrated uptake in 4 cases (10%). Of 15 cases of hepatoma giving negative results in the ^99mTc-PMT study, 7 cases (47%) took up ⁶⁷Ga-citrate, and 6 of these showed increased ⁶⁷Ga-citrate uptake by the hepatic tumors. A certain relation existed between the degree of histological differentiation of hepatomas and the intensity of ^99mTc-PMT uptake by those tumors, while such a histological correlation was denied for ⁶⁷Ga-citrate uptake by the tumors. Delayed ^99mTc-PMT imaging is preferable to ⁶⁷Ga-citrate imaging for increasing the specificity of diagnosis of hepatoma. ⁶⁷Ga-citrate should be used in those cases that do not give positive results with ^99mTc-PMT.     

Clinical approach to renal study incidental to99mTc-MDP bone scintigraphy

In order to investigate the feasibility of the assessment of renal function with 99mTc-MDP, we compared renographical images, renogram patterns and the glomerular filtration rate (GFR) obtained by means of a modified Gates' method and 200 MBq of 99mTc-MDP with those obtained by means of 99mTc-DTPA. Because 19 of 20 patients had malignant tumors in the genitourinary tract, there was no difference between the two tracers in identifying a parenchymal defect corresponding to renal cancer. Of eight patients with hydronephrosis, four had a defect or decreased uptake with a dilated pelvis, whereas the other four had marked radioisotope retention in the renal pelvis or the whole kidney on serial images. There was also no difference between the two tracers in identifying hydronephrosis. Of 38 paired renograms 35 showed the same renogram patterns with both tracers. Of three patients with different renogram patterns, two had hydronephrosis. In 20 patients including three patients with bone metastasis, total GFR and split GFR obtained with both tracers correlated with a correlation coefficient of r = 0.920 (p < 0.001) and r = 0.944 (p < 0.001), respectively. Excluding bone metastasis from the analysis, a linear-regression analysis showed excellent agreement between the two measurements with a correlation coefficient of r = 0.960 (p < 0.001) and r = 0.963 (p < 0.001), respectively. The linear regression equations were Y = 1.009X - 0.111 and Y = 1.034X - 0.714, respectively. In conclusion, 99mTc-MDP can be used as a supplement to evaluate renal function incidental to the survey of bone metastases in patients with malignant tumor.     

Cervical myositis ossificans traumatica: a rare location

An unusual case of myositis ossificans traumatica lesion located in the paraspinal region is reported. Despite the contiguity of the lesion with the cervical vertebrae and ominous appearance of the biopsy material, the history of antecedent trauma and computed tomography findings allowed preoperative accurate diagnosis. To our knowledge, myositis ossificans traumatica located in the cervical paraspinal region is very rare. Received: 9 March 1998; Revision received: 22 May 1998; Accepted: 12 June 1998     

Magnetic resonance imaging of myositis ossificans: analysis of seven cases

Myositis ossificans typically presents as soft tissue swelling with progressive ossification on radiographs. Since magnetic resonance imaging (MRI) is commonly used to evaluate soft tissue masses, we analyzed eight MR examinations in seven patients with myositis ossificans to determine if typical patterns were present. One acute lesion had homogeneous intermediate signal intensity on T1-weighted images and high signal intensity on T2-weighted images. Two subacute lesions had low signal intensity margins with slightly increased signal intensity centers on T1-weighted images and very high signal intensity on T2-weighted images. Five chronic lesions had two different patterns. All five were well-defined with low signal intensity borders. Three had signal intensity patterns characteristic of fat on T1-weighted and T2-weighted images. The other two lesions had intermediate signal intensity on T1-weighted images and slightly increased signal intensity on T2-weighted images.We conclude that typical MR appearances of myositis ossificans do exist. A low signal intensity rim is a common finding. However, these patterns are not unique to myositis ossificans and resemble those that have been reported in other lesions. It is important to be aware of the spectrum of MR findings of myositis ossificans when considering the differential diagnosis of a soft tissue mass.     

99mTc-MDP retention in osteoporosis: Relationship to other indices of bone cell activity and response to calcium and vitamin D therapy

Serum calcium, albumin, phosphorus, and alkaline phosphatase, urinary creatinine and retention of ^99mTc-methylene bisphosphonate (^99mTc-MDP) were measured in 61 subjects with osteoporosis and the values compared with those obtained in normal subjects. ^99mTc-MDP retention was inversely related with urinary creatinine output in normal subjects. In osteoporotic subjects urinary creatinine output was lower and ^99mTc-MDP retention higher even when urinary creatinine output was taken into account. Other measurements were similar. In 21 subjects these measurements together with urinary hydroxyproline were performed before and after treatment with calcium and vitamin D. ^99mTc-MDP and alkaline phosphatase fell; urinary hydroxyproline was unchanged. A single 24 h urine measurement after ^99mTc-MDP injection is a valuable method of predicting whether calcium and vitamin D therapy will be useful in a particular case of osteoporosis.     

Extraosseous 99mTc-MDP uptake in squamous cell carcinoma of the pleura

A rare case of squamous cell carcinoma of the pleura in association with tuberculosis is described. Concentration of ^99mTc-methylenediphosphonate was demonstrated in the calcified pleural tumoral tissue. To the best of our knowledge, such concentration has not been previously reported. The possible etiological factors of this disease and findings are briefly discussed.     

Technetium-99m mercaptoalbumin as a potential substitute for technetium-99m labelled red blood cells

Technetium-99m labelled red blood cells (^99mTc-RBCs) are far superior to ^99mTc-labelled human serum albumin (^99mTc-HSA) for radionuclide ventriculography, but their labelling is more complex, time consuming and risk bearing (in vitro labelling) or suffers from interference by some medications (in vivo labelling). We have now modified HSA by the introduction of mercapto groups with the purpose of preparing stable and practical ^99mTc-mercaptoalbumin with long retention in the vascular system, that could replace ^99mTc-RBCs. HSA was incubated with N-succinimidyl S-acetylthioacetate (SATA) or N-succinimidyl 2,3-di(S-acetylthio) propionate (SATP) to introduce a chain containing one or two protected sulfhydryl groups on some of the lysine amino groups. After purification by size-exclusion chromatography (SEC), the mercapto groups were deprotected by incubation at alkaline pH or by treatment with hydroxylamine. The reaction products were used with or without SEC purification for direct or exchange labelling experiments with ^99mTc at neutral pH. SEC-HPLC was used to determine labelling yields and to isolate pure ^99mTc-mercaptoalbumin. Stable ^99mTc-mercaptoalbumin complexes could be formed in 90%–95% yield after coupling albumin with SATA or SATP in all molar ratios used followed by deacetylation in one of the mentioned conditions. The most favourable results were obtained after reaction of SATA or SATP with HSA in a 25: 1 ratio and deprotection with NH₂OH. The stability of the resulting ^99mTc-mercaptoacetyl-albumin (^99mTc-MAHSA) and ^99mTc-dimercaptopropionyl-albumin (^99mTcDMP-HSA) and their retention in vivo in plasma of mice and rabbits are clearly higher than that of conventional ^99mTc-HSA preparations. ^99mTc-DMP-HSA approaches the behaviour of ¹²⁵I-HSA quite well in both animal species. A preliminary study with ^99mTc-DMP-HSA in a volunteer showed a retention in the vascular compartment almost identical to that of ^99mTc-RBCs and clearly higher than that of a common ^99mTc-HSA preparation. The results indicate that these ^99mTc-mercaptoalbumins and especially ^99mTc-DMP-HSA are very promising as a practical alternative to ^99mTc-RBCs.K.A. Verbeke is a Research Assistant for the Belgian National Fund for Scientific Research     

The stability of 99mTc-DTPA and 99mTc-HIDA following ultrasonic nebulisation

The stability of ^99mTc-DTPA (diethylenetriamine-pentaacetic acid) and ^99mTc-HIDA (2,6-diethylacetanilidoiminodiacetic acid) were evaluated following ultrasonic nebulisation. The results confirm that either of these radiopharmaceuticals can be used in our nebuliser without significant radiochemical breakdown.     

99mTc-labelling of leucocytes with 99mTc-DPO: a complex developed for myocardial imaging

The lipophilic ^99mTc-DPO complex, developed as a myocardial imaging radiopharmaceutical, was used to label leucocytes. After an incubation of 0.1 ml ^99mTc-DPO (8 g DMPE*2HCl) with mixed leucocytes in plasma, the labelling efficiency was over 70%. During incubation in 5 ml plasma, a loss of activity was found between 20% (1 h) and 35% (3 h) caused by elution. Disturbances of cell viability could not be found with the help of the chemiluminescence test. The in vivo recovery was determined in three dogs and was 45%–50% (0.5 h), 30%–36% (1 h), and 18%–24% (3 h). Autologous ^99mTc-DPO-leucocytes were used on seven patients with suspected osteomyelitis, there were four true negative and three true positive results. The target/nontarget ratio determined by ROI in the positive cases was 1.8 to 2.5 at 3 h after injection.     

Uptake of 99mTc-phytate in osteosarcoma cases

During routine liver spleen scintigraphic studies using ^99mTc-phytate in patients with proven osteosarcoma, an unusual uptake of this radiopharamaeutical at the primary site was observed. In all, five cases have been investigated and we have observed the uptake of ^99mTc-phytate at the primary tumor site. Early and delayed imaging showed persistant concentration of the radiopharmaceutical. Studies with ^99mTc-sulfur colloid in one of the patients did not show any uptake at the tumor site.     

Extraskeletal osteosarcoma arising in myositis ossificans

A 53-year-old woman had extraskeletal osteosarcoma that developed from a soft tissue bony mass present on the volar aspect of the left wrist for 4 years. Initially, the bony mass was soft and movable, but during the first year it became hard and fixed. The patient had no history of trauma. Because the lesion did not grow or cause any symptoms, the patient did not come to the hospital until 4 years after she first noticed the lesion. Radiologically, the bony mass had features characteristic of mature myositis ossificans, showing ”eggshell” ossification. A nonmineralized soft tissue mass occurred between the surface of the radius and the bony shell. Histologically, a high-grade osteosarcoma was present between the surface of the radius and the well-differentiated bone tissue, which included fatty and hematopoietic marrow. All the findings indicated that our patient had an extremely rare case of malignant transformation of myositis ossificans. Received: 22 June 2000 Revision requested: 2 August 2000 Revision received: 14 September 2000 Accepted: 25 September 2000