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Biomedical subjects

K Kostić

Publications and source records attributed to K Kostić.

At least 19 recordsLinked to original sources
PubMed2005

[Liver hemangioma blood pool as a function of time].

UNLABELLED: Aim of the study was to determine the time needed for establishing maximal labelled red blood cell concentration in hemangioma by scintigraphic semiquantitative blood pool estimation as a function of time. PATIENTS AND METHODS: Eleven patients (eight females and three males) with total number of fourteen liver hemangiomas have been examined. Nine of them had solitary lesions and remaininig two patients had two and three liver hemangiomas, respectively. All patients underwent blood pool scintigraphy 40, 60, 120 and 180 minutes after in vivo labelling of autologous red blood cells using 740 MBq of 99mTc. After correction for radioactive decay of 99mTc and back-ground correction blood pool indexes, as hemangioma/heart and liver/heart counting rate ratios, have been calculated. RESULTS: Mean blood pool indexes obtained 40-180 minutes after in vivo red blood cell labelling did not differ significantly (p > 0.05) neither in hemangioma (0.84-0.86) nor in liver tissue (0.55-0.58). In every acquisition time hemangioma blood pool index was substantialy higher than that of liver tissue (p < 0.01). CONCLUSION: The results of the study indicates that labelled red blood cells concentration reaches its plateau before 40th minute following in vivo labelling. The concentration difference between hemangioma and liver tissue also does not differ significantly after 40th minute of blood pool examination. In most patients blood pool scintigrams taken 60, 120 and 180 minutes following in vivo RBC labelling do not contribute to diagnostic value of the method.

Erythrocytes↗
PubMed2001

[Study of blood flow in liver hemangiomas using radionuclide angiography].

Hepatic radionuclide angiography (HRA) is a recognised method of investigation of liver blood flow disorders caused by: diffuse and focal diseases of liver parenchyma or disorders of blood flow in extrahepatic liver vessels. Hepatic perfusion index (HPI) based on Sarper's slope method is significantly lower in patients with e.g. liver cirrhosis, malignant primary and metastatic liver diseases and portal vene thrombosis, but not in patients with benign focal liver leasions. Determined in liver as a whole, HPI is a sensitive indicator of the presence of malignant liver tumours, but is within normal range in patients with hepatic hemangioma. The aim of the study was to investigate characteristic of blood flow in hemangioma itself, separately from but in relation to the liver blood flow, using hepatic radionuclide angiography. We have examined 12 patients with liver hemangioma confirmed mainly by positive 99mTc-labeled red blood cell scintigraphy, which diagnostic specificity for liver hemangiomas is near 100%. 8/12 hemangiomas resulted in photopenic areas on angioscintigrams, indicating lower blood flow, and rest were isoactive to surrounding liver tissue. Regions of interest have been delineated around the photopenic areas (hemangiomas) and surrounding liver tissue. Time-activity curves have been generated and slope of the fitted hepatic artery and (portal) venous portions of the hemangioma and liver curves have been determined. Perfusion indexes of hemangioma (PIH) and liver (HPI) have been calculated from the slopes, expressing portal venous flow as a portion of entire blood flow to the region. In addition, times of arrival and transit of intravenous bolus of 99mTc-pertechnetate through the hemangioma and liver tissue have also been derived from time-activity curves. Slope of the venous portion of the hemangioma time-activity curve is significantly lower then that of the venous portion of the liver curve (p < 0.01). So that, perfusion index of hemangioma (PIH = 0.34 +/- 0.12 (mean +/- SD) is significantly lower then hepatic perfusion index (HPI = 0.57 +/- 0.08) (p < 0.05). Bearing in mind interference of superimposed liver activity with that of hemangioma, these results indicate that liver hemangiomas are dominantly if not exclusively irrigated by hepatic artery branches. There are no data regarding relation between arterial and venous blood flow in liver hemangiomas determined by HRA. Obtained results are in harmony with arteriography data which confirm slow arterial blood flow through hemangiomas. Portal venous inflow of some angiomatous liver lesions in infants and children, and arterio-portal shunting in hemangiomas have been rarely reported. Results of this study indicate that regional determination of perfusion index and other HRA parameters in patients with focal liver lesion enables differentiation between tissues with different intensity and pattern of blood flow. The method could be used in examination of vascularisation pattern of other focal liver lesions.

Erythrocytes↗
PubMed1998

Evaluation of gallbladder motility in patients following total gastrectomy (Roux-en-Y) by infusion cholescintigraphy.

BACKGROUND: The aim of the study is to evaluate gallbladder (GB) motor function, by infusion cholescintigraphy, in patients after total gastrectomy (Roux-en-Y) with expected disturbances in the physiological regulation of biliary tract motility. METHODS: The study was done in 10 controls, as well as in 12 patients early (less than 2 months) and in 14 late (6 months-2 years) after surgery. Anterior abdominal imaging by gamma camera and computer acquisition was performed during three-hours infusion of 150 MBq, preceded by the loading dose of 50 MBq of 99mTc-EHIDA in bolus injection. The test meal stimulation was done in the 120th min of the study. GB TA curve was obtained and five parameters of GB motility were analysed: durations of filling (ascending) and emptying (descending) phases, filling and emptying rate ratio and ejection fraction and rate. RESULTS: Our results have shown that in the early period after the operation GB filling is prolonged and emptying impaired, while after several months GB motor function is normalised. CONCLUSIONS: It can be concluded that the infusion cholescintigraphy is potentially useful in patients after such surgery to decide on the specific treatment introduction in order to prevent GB calculosis and other complications.

Journal Article↗
PubMed1995

[Dynamic scintigraphy of gastric emptying in non-insulin dependent diabetics with autonomic neuropathy].

To ascertain whether gastric emptying of solids is affected by visceral autonomic neuropathy, 30 noninsulin-dependent diabetics (10 with autonomic neuropathy, 10 with peripheral and 10 without neuropathy) and 10 control subjects were studied. Subjects were screened by clonidine test and two parasympathetic tests of cardiovascular reflexes to identify the presence of autonomic neuropathy. The peripheral neuropathy was diagnosed by classic neurological examination and EMG. Delayed gastric emptying was assessed by dynamic scintigraphy, using 99mTc labeled ham and eggs. The gastric emptying of solids was markedly delayed in diabetics, particularly in diabetics with poor metabolic control (p < 0.01) and those with autonomic and peripheral diabetic neuropathy (p < 0.05). The results of our study suggest that dynamic scintigraphy may be a more sensitive method than other tests for autonomic dysfunction of the gut in diabetics with the early manifestation of diabetic gastroparesis.

Autonomic Nervous System Diseases↗
PubMed1995

[Gallbladder motor function studied by modified infusion cholescintigraphy method after gastric and duodenal surgery].

Estimation of the gallbladder (GB) motility disorders after gastric surgery has not yet been assessed because of the shortage of the reliable diagnostic methods. The aim of the study is introduction, modification and establishment of the infusion cholescintigraphy into clinical practice and its performance in the groups of patients with gastric resection (RVBI i RVBII), total gastrectomy and patients after gastroplasty. Obtained data produced information about motility disorders caused by billateral truncal vagotomy, lack of the food transit through duodenum and if the motility disorders are the same in different time periods after operation. In groups of patients without truncal vagotomy (RVBI and RVBII), minor motility disorders are registered in comparison to the groups after truncal vagotomy. In the period of 6 months after surgery, higher motility disorders are registered in the group of patients with total gastrectomy, while after 9-12 months GB motility completely recovers. Groups with preserved transit of food through duodenum (RVBI and gastroplasty), has minor motility disorders in comparison to the group without transit of food through duodenum (RVBII and total gastrectomy). By introducing infusion cholescintigraphy, reliable method for the GB motility assessment is obtained.

Adult↗
PubMed1993

[Quantitative analysis of gallbladder function using quantitative dynamic radionuclide cholecystography].

The aim of the study is to demonstrate general function of the cholecyst through selected quantitative parameters derived from the quantitative radionuclide cholecystography method, using our own computer software HIDATA, and to evaluate values of specific quantitative parameters in 15 patients presenting with chronic calculous and 15 with chronic acalculous cholecystitis. A control group comprised 10 subjects with no changes on the cholecyst. Of four quantitative parameters calculated during cholecyst filling, the only significant one was the ascending segment slope of the curve from specific ROI, that is, K1 derived from it, because it shows its functional status, depending on the changes in its wall and the lumen content. The most significant parameters which maintain motor function of the cholecyst are ejection fraction (EF) and ejection rate (ER) which are always decreased in chronic cholecystitis, regardless of the presence of calculosis and the number of calculi in the lumen. The ejection fraction is especially decreased in the multiple sclerosis group; it is significantly decreased when compared with acalculous chronic cholecystitis. Our results indicate that a selection of parameters used in clinical practice for the assessment of the cholecyst function is necessary. Our program HIDATA included a large number of parameters of which three were classified as important for the assessment of the cholecyst function (K1, EF, ER), reflecting the process of filling and emptying of the cholecyst and offering reliable and valuable data for the treatment.

Cholecystitis↗
PubMed1993

The role of biphasic scintigraphy with 99mTc-HMPAO leukocytes in detection of synthetic vascular graft infections--preliminary results.

The study presents preliminary results and suggests the role of scintigraphy of synthetic vascular prosthesis by 99mTc-HMPAO labelled leukocytes for detection of graft infections. Analysis of the results obtained revealed true positive in 6, true negative in 3 and suspicious findings in 3 patients (in one of them the suspicious was confirmed on reoperation). False positive and false negative results were not obtained. Early and accurate diagnosis of occult infection of the synthetic vascular graft is of utmost importance for the prompt starting of the therapy. Due to its high sensitivity and specificity, 99mTc-HMPAO-leukocytes scintigraphy is a very useful method for the detection of graft infections.

Blood Vessel Prosthesis↗
PubMed1993

Estimation of the gallbladder motility after meal stimulation in the postgastrectomy patients by infusion cholescintigraphy.

The aim of this study is the assessment of the gallbladder (GB) motility in the controls without (C) and with (Cs) test-meal stimulation, as well as in the patients early (EPG) and late (LPG) after total gastrectomy. Data were collected with ROTA scintillation camera, during (3 h, 10 ml/h) infusion of 150 MBq, 0.25 mg/ml 99mTc-EHIDA, preceded by a loading dose (0.5 mg/ml, 50 MBq). While in EPG, GB motility is impaired, it achieves physiological values in LPG patients, which can be attributed to establishment of corresponding hormonal mechanisms, in the late postoperative period.

Eating↗
PubMed1992

Labelling of leukocytes with 99mTc-HMPAO for scintigraphy of inflammatory lesions and abscesses.

A simplified and efficient procedure for 99mTc-HMPAO-labelling of leukocytes is described. For this purpose, the pH and concentration of the 99mTc-HMPAO preparation was modified. Leukocytes were isolated from a 20 mL mixture of patient blood, 5 mL ACD and 0.8 mL methylcellulose after 1 h sedimentation of erythrocytes and centrifugation (at 400 g) of the obtained plasma layer. Simultaneously, 99mTc-HMPAO was prepared (one single-dose kit for two patients) by adding 2.2 mL 99mTc-generator eluate and, after 10 min, 0.3 mL of phosphate buffer to lower the pH to 7. The isolated WBCs were then labelled by the addition of 1-1.2 mL of 99mTc-HMPAO solution and incubated for 20 min. The unbound tracer was then discarded, the labelled WBC washed and finally resuspended in autologous cell-free plasma. Leukocytes labelled by this procedure were used for scintigraphic localization of inflammatory lesions and abscesses in the gastro-intestinal tract. The labelling efficiency was 60 +/- 9%, with a separation yield of 55 +/- 11%.

Abscess↗
PubMed1987

Chemical and biological properties of 2,6-diisopropyl IDA labelled with 99mTc.

A procedure is described for the synthesis of 2,6-diisopropyl IDA (DISIDA) and for preparation of the radiopharmaceutical by "instant technique". The chemical parameters affecting the formation of the Sn(II)-DISIDA complex were also determined. Biological studies involved lyophylic measurements, determination of binding constants as well as rate of binding to proteins and biodistribution. Clinical investigation demonstrated good hepatobiliary features of this radiopharmaceutical.

Adult↗
PubMed1985

Studies of the chemical and biological properties of the liver-imaging agent 99mTc-phytate.

The correlation between chemical formulation and biodistribution of 99mTc-phytate solutions was examined. On the basis of radiochemical analyses and biological experiments, the following optimum parameters were found: weight ratio of the anhydrous sodium phytate to SnCl2 18:1; concentration of phytate 5-6 g/l, pH of the injection solution 6-7. Maximum uptakes in rat organs were in the liver 95.8 +/- 3.26 at 15-20 min p.i., and in the spleen 3.98 +/- 0.79% 3 hours p.i. Two new methods for radiochemical analysis enabling the separation of three peaks were used: ITLC-SG Gelman chromatography and molecular sieving through Sephadex G-25. The bench-life of the injection solution was also checked during a 5-h period, as well as its shelf-life which was at least 6 months. Clinical examinations showed excellent visualization of the normal liver with discrete radiocolloid uptake in the spleen and no uptake in other tissues. With SPECT a more precise and clear localization of liver lesions was achieved especially due to the low uptake of 99mTc-phytate in the spleen.

Animals↗