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Nuclear medicine, diagnostic and therapeutic application of open sources of ionizing radiation in medicine, has wide range of possibilities for non-invasive infection and inflammation detection. The broad spectrum of methods, some of which are already in routine use while the others are still in the phase of investigation, improvement, or clinical trials, is presented. Most of the methods in routine use are capable of detection and localisation of both inflammation and infection. Antibiotic and antimicrobe peptides labelings have the possibility to diagnose infection and to differentiate it from inflammation, which is not the case with other scintigraphic methods. Availability of the radiopharmaceuticals and nuclear-medicine equipment, radiation exposure of the patient, clinical situation, the baseline pathophysiology of a process, and costs are the factors which contribute to the choice of the diagnostic approach. In order to ease the choice of the appropriate diagnostic method for inflammation/infection detection in different clinical situations, the recommendations from the ISORBE (International Society of Radiolabelled Blood Elements) are quoted.

The aim is the assessment of the HP infection in stomach using breath test and comparison to other diagnostic methods, as well as following up the effect of therapy. In 83 patients with digestive discomfort rapid urease test, histology and breath test were performed, while in 25 patients with proven HP infection the effect of therapy was followed up using breath test and clinical findings. For rapid urease test and histology, samples were taken from antral mucosa. Breath test was performed after per oral administration of the capsule of 14C- urea (37 kBq) (Izotop, Hungary and Laboratory for radioactive isotopes, Vinca) which, in the presence of Helicobacter pylori breaks up to 14CO2 and NH3. Radioactivity was measured by beta counter in the exhaled air fasting and 30 minutes after ingestion of the capsule. According to our results, the rise of activity over 100% was considered positive. From 83 patients, 58 were breath test was positive, 24 negative and one equivocal. Fast urease test was in 54 positive, in 29 negative while histology was in 57 postitive and 26 negative. Findings of the breath and urease tests were in accordance in 93% patients while breath test and histology in 98% patients. During follow up of the therapeutic effects, breath test and clinical findings were in accordance in 98% patients. Breath test can be useful in diagnosis but is a method of choice in following up the patients after therapy for H. pylori infection, because it is non-invasive, fast and precise.

The aim of the study is detection and evaluation of the orthopedic infections using 99mTc-ciprofloxacin, radiopharmaceutical supposed to distinguish inflammation from infection. There were 15 true positive findings, 9 true negative, and two were false positive, while 1 was false negative. Sensitivity was 94%, specificity 82%, positive predictive value 88%, negative predictive value 90% and accuracy 89%. According to our results, scintigraphy with 99mTc-ciprofloxacin is a useful method for detection and assessment of exact localization of orthopedic infections, which might be useful for (differential) diagnosis, surgical treatment in due time as well as monitoring of the treatment of conservative therapy.

Taking into consideration the existing disagreement in the literature, the aim of this paper was to estimate the value of the initial kinetics of autologous platelets labelled with 111In-oxinate, performed during the first 20 minutes after their intravenous injection. Two hypothesis were tested: 1. Initial 111In-platelet kinetics indicates the platelet sequestration site (in patients with normal mean platelet life span)/destruction site (in patients with shortened mean platelet life span), 2. Initial 111In-platelet kinetics indicates the quality of platelet separation and labelling procedure. We performed initial labelled platelet kinetics in thrombocytopenic patients (in order to test the first hypothesis) as well as in control (healthy) subjects (in order to test the second hypothesis). Thirty-nine persons were investigated: 33 with thrombocytopenia: 25 with shortened mean platelet life span, caused by chronic im mune thrombocytopenic purpura (ITP), eight with normal platelet life span and thrombocytopenia caused by myelodysplastic syndrome (MDS), six healthy, control subjects (C). In all 39 persons platelet blood count on the day of platelet labelling was determined, autologous platelet labelling with 111In-oxinate was performed, general and differential yields of platelet labelling (GYL and DYL), as well as mean labelled platelets life span were determined. Besides that, initial labelled platelets kinetics was performed with initial 111In-platelets accumulation in the liver (IPAL) calculation, as well as the late platelet kinetics for platelet sequestration index and platelet sequestration/destruction site determination. We obtained two types of initial labelled platelets kinetics (not only in the patients with shortened platelet life span, but also in the subjects with normal labelled platelets life span), which differed in the IPAL value and in the ratio of the liver and the heart radioactivity: IPAL < 20% and IPAL>20%. We found statistically significant difference in GYL and DYL between the two groups: IPAL<20% and IPAL > 20%. Both yields were higher in IPAL<20% group. There was no significant difference between the two IPAL groups in the platelet blood count, labelled platelet life span, sequestration index and sequestration site. No correlation could be found between IPAL on one side and platelet blood count, sequestration index, and sequestration site on another. We concluded that initial labelled platelet kinetics could not indicate the platelet sequestration/destructon site (which is accomplished by the late labelled platelets kinetics), but nevertheless, it is very sensitive and useful method of platelet separation and labelling quality control. While in vitro quality control parameters (GYL and DYL) indicate the quality of only one part of this procedure, initial labelled platelet kinetics reflects discrete platelet function disturbance that might happen from the moment of blood sample collection till the labelled platelets intravenous injection.

The purpose of this study was to point out the existing methods and to describe and evaluate the accuracy of new, original, "Geometric-count-based" (GCB) method, based on radionuclide ventriculography, for the measurement of left ventricular volumes compaired to the contrast ventriculography. By having done this, the aim was to compare the accuracy of GCB method and other two radionuclide methods available for left ventricular volume measurements: Count-bases Massardo method and gated blood pool SPECT method. In GCB method count based data from radionuclide ventriculography were combined with geometric ones assuming a prolate ellipsoid left ventricular's shape with identical short axes. The following equation for computing left ventricular end-diastolic volume was developed: EDV = 2 x c x M x C(tot)/C(max), (1) where: 2c--manually drown short axis of prolate ellipsoid (left ventricle) at end-diastolic frame, M-calibrated pixel size, C(tot)--total counts in left ventricular's region of interest at end-diastolic frame, C(max)--maximum pixel counts in left ventricular's region of interest. Physical experiments with two different heart shaped phantoms were used to compare volumes assessed by all three radionuclide methods with the true volumes. The true volumes of cylindrical and ellipsoid phantoms of 112.5 ml and 190.5 ml, were computed to be 114 ml and 196 ml by our GCB method, 168 ml and 180 ml by Massardo method and 142 ml and 222 ml by gated blood pool SPECT methods, respectively. In clinical study, in 65 patients volumes assessed by radionuclide methods were compared to volumes measured using single plane contrast ventriculography as a gold standard. A good correlation of our original method was obtained with a contrast ventriculography for both EDV/m2 and ESV/m2 (r = 0.94, r = 0.92), slightly lower for Massardo method (EDV/m2: r = 0.90, ESV/m2 : r = 0.89) and significantly lower for gated blood pool SPECT (EDV/m2: r = 0.85, ESV/m2: r = 0.81, p < 0.01). In conclusion, both, phantom and clinical studies indicate that GCB radionuclide method is accurate, noninvasive for left ventricular volumes' measurement and should be widely used in everyday clinical practice.

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.

The aim of this investigation was to estimate the possibility of predicting the splenectomy response in patients with chronic immune thrombocytopenic purpura (ITP). The patients' age, sex, megakaryocytes abundance, platelet blood count, production, life span, sequestration/destruction site were considered as possible predictive factors. Thirty-four ITP patients (23 female and 11 male) aged from five to 83 years were investigated. Platelet blood count ranged from 4 to 106 x 10(9)l (mean value was 43 x 10(9)/l). Megakaryocyte abundance was determined in 19/34 ITP patients. Megakaryocytes were numerous in 11/19, present in 7/19 ITP patients and in one patient low megakaryocyte number was registered. In all 34 ITP patients autologous platelet labelling with 111In-oxinate was performed and labelled platelets were reinjected to the ITP patients. This enabled platelet life span, production, sequestration index and sequestration/destruction site determination. Platelet life span ranged from 0,4-5 days (mean value was 1 day). Mean value for platelet production index was 1,1. Platelet sequestration/destruction site in 16 ITP patients was the spleen, and in two it was the liver. Mixed platelet sequestration/destruction site (the liver and the spleen) was registered in 7 ITP patients, while predominantly splenic sequestration/destruction was present in 9 ITP patients. All 34 ITP patients were later submitted to splenectomy, which is a therapeutic option in ITP. Splenectomy result was favorable in 28/34 ITP patients while it was unfavorable in 6/34 (17,6%). Highly significant correlation was noticed between the splenectomy result and platelet sequestration site (p < 0.01). On the other hand, there was no correlation between the splenectomy result on one side, and patient's age, sex, megakaryocyte abundance, platelet production, life span and blood count on the other. Splenectomy result was favorable in all ITP patients with splenic sequestration/detruction of labelled platelets. It was unfavorable in ITP patients with hepatic sequestration of labelled platelets. In ITP patients with mixed platelet sequestration (hepatic and splenic) there were more unfavorable than favorable splenectomy results. Non-invasive method of platelet labelling and platelet sequestration/ /destruction site determination makes easier the clinicians' and ITP patients' decision for the splenectomy in the case when the spleen is the only sequestration site of the labelled platelets, and against the splenectomy, when exclusively hepatic platelet sequestration/destruction is registered.