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The diagnostic capacities of 99mTc-pyrophosphate plane myocardial scintigraphy versus 99mTc-pyrophosphate single photon emission computed tomography (SPECT) were compared. Recording right precordial ECG leads showed that 26 patients had right ventricular myocardial infarction (MI)-typical changes as ST-segment evaluation, followed by abnormal Q wave. Plane scintigraphy indicated a characteristic inclusion of 99mTc-pyrophosphate into the right ventricular myocardium in 18.8% of the patients with acute lower MI and in one of 38 patients with acute MI of the anterior left ventricular wall. SPECT revealed a characteristic inclusion of 99mTc-pyrophosphate into the right ventricular myocardium much more frequently than did plane myocardial scintigraphy--in 34% of cases. Right ventricular myocardial inclusion of 99mTc-pyrophosphate was found in 50% of the patients with acute lower MI, including all 9 patients with positive 99mTc-pyrophosphate myocardial scintigraphy. Thus, the sensitivity of SPECT in the diagnosis of right ventricular MI is somewhat higher than that of precordial ECG and more than thrice higher than that of plane scintigraphy.

Myocardial scintigraphy with 99mTc-pyrophosphate is a widely used highly sensitive and specific method for the evaluation of patients with acute myocardial infarction (AMI) with optimum visualization within 24-72 h after the onset of chest pain. In some cases the so called doughnut-shaped 99mTc-pyrophosphate myocardial scintigrams may occur. As a rule patients with scintigraphic images of this type have a poor prognosis. Old-aged patients are characterized by peculiar features in the interpretation of 99mTc-pyrophosphate myocardial uptake. Findings of 4 patients aged 88 to 92 (2 patients with verified AMI and 2 CHD patients without AMI) with doughnut-shaped 99mTc-pyrophosphate myocardial scintigraphic images were analyzed. The authors present two case reports of aged patients with AMI and without it with this type of myocardial uptake and one case report of a 50-year old patient with vast anterior myocardial infarction with a poor prognosis and doughnut-shaped 99mTc-pyrophosphate myocardial scintigraphy. In old-aged patients the uptake of 99mTc-pyrophosphate in the myocardium may occur not only with but also without AMI as a result of increased calcification. These features should be taken into account while establishing correct diagnosis.

The proposed method of sequential scintigraphy of the kidneys and joints in a single administration of 99mTc-pyrophosphate permits obtaining objective information on function and topography of the kidneys and pyodestructive processes in the joints. Dynamic scintigraphy helps to assess visually renal hemodynamics and the antomotopographic position of the kidney and to obtain exhaustive information on accumulative-evacuatory function of each kidney individually. Scintigraphy also helps to investigate all the joints and to detect pyoinflammatory changes in them. The proposed method considerably reduces the time of investigation and lessens radiation exposure of patients, permitting repeated investigations to assess and correct the treatment of patients with rheumatic arthritis.

Assessment of myocardial contractility function and its diastolic features (according to the results of radionuclide ventriculography with 99mTc-pertechnetate) in patients with dilatory cardiomyopathy (DCMP) revealed a significant decrease in the total ejection fraction, regional ejection fractions, cardiomegaly (an increase in the end-diastolic volume combined with an increase in end-systolic volume and a decrease in the stroke volume) and a decrease in ejection rate indices. Differential criteria for the diagnosis of DCMP and CHD were a greater degree of cardiodynamic indices and a diffuse decrease in myocardial regional contractility function in the former and heterogeneity of changes in regional contractility in the latter pathology. The process of diastolic filling in DCMP patients was characterized by a marked decrease in a filling rate at reduced time of its achievement, and in CHD patients by a decrease in a maximum filling rate in combination with increased time of its achievement.

Angioscintigraphy was used for examination of 128 patients, of them 91 had tumors of the genital organs, 22 inflammatory adnexal processes and 15 various extragenital diseases. Statistical scintigraphy was performed 5-40 min. after RP intravenous injection at 175-555 MBq. RP injection was followed by dynamic studies, the rate of recording being 1 frame per min. An anterioposterior direct projection with alignment of a gamma-chamber detector over the small pelvic area was used. 99mTc-human serum albumin and erythrocytes labeled in vivo with 99mTc-pyrophosphate served as radioactive markers of the blood pool. A scintigraphic picture in normal and pathology (tumors and inflammatory processes) in the uterus and appendages had characteristics features. Data on a degree of tumor vascularization could be used for recognition of disease as well as for adequate assessment of therapeutic efficacy. The sensitivity of the method was 97%, its specificity--59%, its accuracy--88%.

Diagnostic potentialities of investigation of the kidneys using 99mTc-pyrophosphate were studied in 34 patients with rheumatoid arthritis (RA) for articular scintigraphy. The results obtained were compared with those of radionuclide renography with 131I-hippuran and excretory urography. A possibility of investigation of the kidneys with 99mTc-pyrophosphate for the assessment of parenchyma function and kidney urodynamics was shown. Taking into account a high prevalence of nephropathy in RA patients, dynamic renal scintigraphy and clearance registration were recommended at the first stage of articular scintigraphy with 99mTc-pyrophosphate in order to obtain information on the anatomotopographic site and accumulation-evacuatory function of the kidneys.

A new Soviet osteotropic agent 113mIn-indifor was used in clinical practice in 88 patients with primary (56), secondary (22), and systemic (10) skeletal diseases. The sensitivity of the method was 87.7%, its specificity--75%. The main indication for its use was a search for new or additional metastatic foci in malignant tumors of various sites. Investigations using 113mIn-indifor and 99m Tc-phosphates were conducted in 35 patients with different skeletal lesions. The authors obtained the results indicating the same informative value of both radiopharmaceuticals--90.3%. In view of some difficulties in supplies of generators of technetium, 113mIn-indifor can replace 99m Tc-phosphates in routine investigations of primary and especially metastatic skeletal lesions.

The paper is concerned with the results of radionuclide investigation of 51 patients with different tumors located beyond the osseous tissue. In spite of the fact that 99mTc-phosphates were well known as agents for radionuclide diagnosis of bone tumors, they can be employed for obtaining certain diagnostic information concerning topical diagnosis and the determination of a degree of the distribution of processes of nonskeletogenous nature. Of 51 patients with soft tissue pathology clear visualization of lesion foci was obtained in 34 patients (66.7%). Positive results of radionuclide diagnosis with 99mTc-pyrophosphate were noted in scintigraphy of patients with breast, ovarian, soft tissue and maxillofacial tumors. Besides, clear visualization of lesion foci was achieved in 6 of 11 patients with benign diseases: postoperative scars, inflammatory infiltrates, synovioma. The results obtained indicated the absence of necessary specificity of 99mTc-phosphates to osseous tissue.

Altogether 106 patients with different types of acute CHD (large and small local MI, unstable angina) and stable angina were investigated. Combined assessment of perfusion disorder permits differentiation of necrotic and ischemic myocardial lesions. A degree and type of RP accumulation corresponds to a size of necrotic myocardial lesion determined by means of biochemical markers of necrosis. Parallelism of myoglobin concentration, isoenzyme activity in the blood serum and the results of scintigraphy was revealed. In focal RP accumulation, myoglobin concentration reached maximum values; a moderate increase and decrease up to normal values in the absence of accumulation were observed in diffuse accumulation. Diffuse RP accumulation in patients with stable and unstable types of angina was indicative of transient perfusion disorders resulting from myocardial ischemia.

The general and regional contractility of the left ventricle was studied in 69 patients with chronic coronary heart disease (CHD) and in 10 practically healthy persons using the method of radionuclide ventriculography (RNVG). The contractility indicators in dynamic and static RNVG were correlated. A high degree of correlation was obtained between them as well as with the findings of radiopaque ventriculography. It was established that data processing with the help of a cardiosynchronizer is of high informative value, significant and can be used in RNVG variants thus making it possible to use the same program of processing. The frequency of the methods and mean dispersion of the results were assessed. Numerical values of the general and regional contractility in healthy persons and in patients with varying severity of chronic CHD were determined.

A total of 401 patients: 148 men, 134 women and 119 children with Hodgkin's disease were examined to determine the diagnostic value of the radioisotope and x-ray methods in the early detection of metastatic involvement of the skeletal bones. Specific skeletal bone lesions were revealed in 72 patients. Metastatic lesions of the skeletal bones develop more frequently in adults than in children. No significant differences in the site of metastases were noted. Radioisotope examination is an earlier diagnostic method in the early detection of metastatic involvement of the skeletal bones in Hodgkin's disease and more informative in the diagnosis of costal and cranial bone lesions.

A study was made of reparative osteogenesis and the content of mineral bone components in 60 patients with spiral fractures of the leg bones during treatment by transosseous osteosynthesis. The time of maximum labeled pyrophosphate accumulation was determined by a degree of the initial dislocation of fragments: in the dislocation to the cortical layer it was noted on the 42nd day, by 1/3 on the 45th day, by 2/3 on the 50th day, to the cross section on the 60th day. The demineralization of bone fragments in the dislocation to the cortical layer was 34%, by 1/2 37%, by 2/3 41% and to the cross section by 44%. The labeled sulphuric colloid accumulation by bone marrow cells was maximal in minimal dislocations and decreased with growing dislocation.

The paper is concerned with some comparative data on the frequency of the detection of sacroileitis using clinicoroentgenological and scintigraphic studies in 57 patients with chronic monarthritis of the knee joint of different genesis. On clinical examination 14 patients (24.7%) only had indirect signs of the affected sacroiliac joints, in 30 patients (52.6%) sacroileitis was diagnosed by x-ray. Scintigraphy with 99mTc-pyrophosphate proved to be most effective for the detection of early signs of sacroileitis because lesions in the sacroiliac joints were found in 35 patients (61.4%).

The authors present a method with the use of 99mTc-pyrophosphate for differential diagnosis of malignant and benign ovarian tumors. A total of 46 patients were examined. Of these, the sample hyperfixation in the zone of malignant ovarian tumors with the rate of differential accumulation of 200-260% was observed in 7. In benign tumors and inflammatory ovarian changes, radiopharmaceutical hyperfixation was either not observed or it did not exceed 130%. Diagnosis in all the patients was verified at operation with subsequent histological examination.

Roentgenoradiological control of a reparative process after diaphysial comminuted shoulder fractures was exercised at all stages of the treatment after G. A. Ilizarov's method. Osteoscanning permitted the assessment of the viability of bone splinters on the first days after trauma and quantitative assessment of the activity of osteogenesis. A study of the optical density of radiograms provided an opportunity for evaluation of mineral content in regenerating bones, their structure only at late stages of treatment when it was rather high.

The optimum value of diagnostic procedure in the assessment of RP tumoritrophism (99mTc-pyrophosphate) was shown. The results of radionuclide studies using 99mTc-pyrophosphate in 193 patients with bone pathology were cited by way of example. Diagnostic thresholds with error levels were established. The diagnostic criteria (sensitivity, specificity, accuracy, etc.) were established proceeding from the criteria of malignant and benign features. Some differential-diagnostic potentialities of 99mTc-pyrophosphate in the recognition of certain groups of bone pathology were revealed.

The time course of metabolic processes in the osseous tissue and the capillary blood circulation in the forming osseous regenerate and the bone as a whole were studied in 16 patients using pyrophosphate and DTPA. The results of radiometry made it possible to give a quantitative evaluation of regeneration intensity: during intensive osteogenesis the accumulation of labeled pyrophosphate increased up to 720%, and the capillary blood circulation speeded up to 380%. Before the completion of osteogenesis the drug accumulation decreased considerably up to 250%.

In static scintigraphy with 99m Tc-pertechnetate of primary lesions of the retroperitoneal space in children 4 types of scintigraphic pictures were singled out for differential diagnosis of Wilms' tumors, avascular benign lesions of the retroperitoneal space and neurogenic retroperitoneal tumors. The sensitivity of diagnosis of Wilms' tumor was 92.6%, specificity 90.9%. The most objective and complete information on the kidney involvement in tumor process could be obtained in static scintigraphy with 99m Tc-pertechnetate combined with scintigraphy with 99m Tc-gluconate or 99m Tc-pyrophosphate. The sensitivity of diagnosis of secondary lesions of the lymph nodes of the retroperitoneal space was 76.8%.

It was shown in experiments on albino rats that their adaptation by a series of "trainings" or a course of treatment with Rhodida rosea extract produced a marked cardioprotective effect during emotional-pain stress. Adaptation of rats to stress factors induced simultaneously regular changes of the cyclic nucleotide content in the myocardium, thus contributing to reduction of the adrenoreactivity of the heart and the degree of the stress damage to the myocardium.

A total of 86 patients were examined by 99mTc-pyrophosphate in the course of therapy using the transosseous synthesis method. An elevated accumulation of the radiopharmaceutical was observed since the first day following a trauma. Maximum enhancement of metabolic processes in the absence of fragment displacement was noted on the 8th week and in the lack of displacement on the 9th-10th week. Then the intensity of bone formation got weaker. It was found appropriate that G. A. Ilizarov's apparatus should be removed exactly at that time. The content of mineral components in the regenerate was over 60% which demonstrated the bone ability to stand physiological loads.

The doses of irradiation of patients during the use of 99mTc-pyrphotech and 113mIn-indifor have been defined on the basis of their pharmacokinetics. The data has been obtained with the use of radiometer of human radiation, the method of organs screening during radiometry, and of the gamma-camera and blood samples radiometry. The calculations have been performed in accordance with the known method based on the heterogeneous model of the "standard" human. In the dose calculations for bone tissue and for the red marrow the dosimetry model is used and the values of absorbed fractions recommended by the ICRP. The absorbed and equivalent doses of irradiation of different organs and systems in human organism have been defined. The required values of quality index have been calculated using the spectrum of absorbed dose on the scale of linear transfer of energy for all radiations of the analysed nuclides. The obtained values of efficient equivalent dose are 8.6 and 16 MeV/MBq for 113mIn-indifor and 99mTc-pyrphotech correspondingly.

Altogether 56 patients aged 20-55 with closed oblique fractures of the upper and lower limb bones were observed. Reparative osteogenesis was studied using 99mTc-pyrophosphate. An elevated RP accumulation at the ends of the bone splinters was found from the 1st day after fracture. By the end of the 1st month after fracture the RP activity increased up to 750% in the absence of splinter dislocation. In dislocation it was 50-80% less. The RP maximal activity in the place of fracture was noted on the 7-8th week, in the dislocation of splinters on the 9-10th week. By the results of radionuclide studies, the fracture consolidated right after a decrease in the 99mTc-pyrophosphate accumulation that made it possible to determine the optimum time of bone consolidation.

Data on 97 patients were analysed. Of these, 42 received combined therapy, 30 radiotherapy and 25 chemotherapy. The utmost therapeutic effect (by the selected criteria) was obtained with combined treatment (88.1%). Radionuclide signs of the efficacy of radiotherapy were noted in 70% of the patients, whereas 23.3% did not respond. The least effect was obtained with chemotherapy: the absence of improvement or deterioration were noted in 48% of the patients. The correlation of the data obtained with the clinical ones (the painful syndrome) was observed. A high sensitivity of the method does not only help reveal pathological skeletal changes but also plan adequate therapy.

A scintigraphic picture was observed in 51 patients suffering from breast cancer with metastatic involvement of the skeleton (polychemotherapy + radiotherapy of pelvic bones and lumbar spine + hormonotherapy) to determine the role of scintigraphy in the assessment of therapeutic effectiveness. According to scintigraphic signs of changes in RP accumulation in metastases the following groups were singled out: a complete effect, a partial effect, stabilization, progression of disease. The mean interval from the onset of therapy up to the appearance of scintigraphic signs of a therapeutic effect was 8.6 mos. A high degree of correlation between scintigraphic signs of a therapeutic effect and the time course of the pain syndrome in the skeletal bones was shown.

Altogether 123 angina patients were examined using electrocardiography and scintigraphy of the myocardium with two 99m Tc radiopharmaceutical complexes: pyrophosphate and phosphone. A comparative analysis of the results obtained with different methods of investigation before and after an attack of angina pectoris was made. The authors have shown some peculiarities of radionuclide distribution in the myocardium and the diagnostic value of each method of investigation in patients with different clinical forms of angina pectoris.

The authors presented the results of clinical, x-ray and osteoscintigraphic investigations of 133 psoriatic arthritis patients and 72 patients with common psoriasis. Osteoscintigraphy was performed using a routine method with 99mTc-pyrophos (USSR) and 99mTc-phosphone (Hungary) on gamma-camera LFOV (Nuclear-Chicago, USA). X-ray signs of the involvement of the osteoarticular system were noted in 69 (51%) patients with psoriatic arthritis and in 16 (22%) patients with common psoriasis. The method permitted the detection of the foci of RP hyperfixation in 129 (97%) patients with psoriatic arthritis and in 51 (70.8%) patients with common psoriasis. They were observed mostly in large and small limb joints, less frequently--in the vertebral column, cranial bones, thorax, and ribs. Thus, osteoscintigraphy is a highly sensitive method for the detection of active inflammatory foci of the osteoarticular system in psoriasis at all stages of arthritis development. It makes it possible to detect the spreading of arthritis and its preclinical forms.

Nephroscintigraphy using a 67Ga-citrate complex and 99mTc-pyrophosphate was performed in 88 patients with acute pyelonephritis. Nuclide hyperfixation was revealed in 97.8% of the cases. Three groups of patients were singled out on the basis of the intensity of incorporation and nature of the distribution of the radiopharmaceuticals (RP) in the kidneys. In the 1st group the RP incorporation was insignificant but higher than normal values; the RP distribution in the affected kidney was diffuse-inhomogenous. These changes were considered to be typical of acute serous pyelonephritis. In the 2nd and 3rd groups a sharp rise of the RP accumulation was noted, being typical of acute purulent pyelonephritis. One could distinguish between diffuse and focal lesions by the picture of the RP distribution in the renal parenchyma. Diuresis stimulation made it possible to differentiate an actual nuclide fixation during inflammation from nuclide mechanical retention as a result of urine outflow disorder. According to the authors, both radiopharmaceuticals could be applied for the diagnosis of acute pyelonephritis as well as for differential diagnosis of various forms of the disease.

As for the frequency of metastases to the bones breast cancer ranks third among all tumors, as for the general frequency of metastases it ranks first (25-45%). Early diagnosis of breast cancer metastases to the bones using scintigraphy of the skeleton in the preoperative period gives an opportunity to reveal tumor dissemination and to provide adequate treatment without imposing on patients inappropriate therapeutic measures. The study was performed using 99mTc-pyrophosphate. In revealing the foci of high activity accumulation by more than 20% as compared to symmetrical or adjacent zones, the changes were looked upon as metastatic ones. Out of 85 patients foci of high activity accumulation in the skeleton were noted in 7 (8.3%). In 5 patients, metastases were confirmed directly on roentgenography, and in 2 patients, they manifested themselves 2 and 5 months later. Stage I-IIa disease was observed in 48 (56.5%) out of the 85 patients. Out of the 40 patients with Stage I disease, skeletal metastases confirmed by x-ray were found in 2. All 7 patients were given together with mastectomy adjuvant treatment. Thus scintigraphy of the skeleton together with chest x-ray, liver scintigraphy, physical examination and palpation should become obligatory in the preoperative examination of patients to specify breast cancer stage.

The results of phantom studies have shown that tomoscintigraphy makes it possible to define the localization and size of RP diffuse incorporation in the "myocardium" and to differentiate between true and false-positive results. A rarefaction in the center of an image obtained on a transverse tomographic section should be regarded as a characteristic feature of true RP diffuse incorporations.