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Purpose We aimed at examining both the incidence and extent of different lung perfusion abnormalities as well as the relationship between them on Tc-99m macroaggregated albumin (MAA) perfusion-only SPECT/CT scans in COVID-19 patients. Methods Ninety-one patients (71.4 ± 13.9 years; range: 29–98 years, median age: 74 years; 45 female and 46 male) with confirmed SARS-CoV-2 virus infection were included in this retrospective study. After performing perfusion-only Tc-99m MAA SPECT/CT scans, visual, semi-quantitative assessment of the subsequent perfusion abnormalities was carried out: mismatch lesions (MM; activity defects on SPECT images identical to apparently healthy parenchyma on CT images), matched lesions (MA; activity defects with corresponding parenchymal lesions on CT scans), and reverse mismatch lesions (RM; parenchymal lesions with preserved or increased tracer uptake). Lesion-based and patient-based analysis were performed to evaluate the extent, severity, and incidence of each perfusion abnormality. Statistical tests were applied to investigate the association between the experienced perfusion impairments. Results Moderately severe parenchymal lesions were detected in 87 (95.6%) patients. Although, 50 (54.95%) patients were depicted to have MM lesions, the whole patient cohort was mildly affected by this abnormality. MA lesions of average moderate severity were seen in most of the patients (89.01%). In 65 (71.43%) patients RM lesions were found with mild severity on average. Positive association was detected between total CT score and total RM score and between total CT score and total MA score. Significantly higher total CT scores were experienced in the subgroup, where RM lesions were present. Conclusions Heterogeneous perfusion abnormalities were found in most of COVID-19 patients: parenchymal lesions with normal, decreased or increased perfusion and perfusion defects in healthy lung areas. These phenomena may be explained by the failure of the hypoxic pulmonary vasoconstriction mechanism and presence of pulmonary thrombosis and embolism.

Background: Cerebral blood flow abnormalities are supposed to be potential risk factors for developing cognitive dysfunction in the general population. Aging, obesity and type 2 diabetes mellitus are associated with perfusion abnormalities leading to cognitive impairment, neurodegeneration and future development of dementia. In our study, we aimed at identifying independent factors that contribute to the appearance of regional brain perfusion changes besides those that are already known. Material and methods: Forty-three type 2 diabetic and twenty-six obese patients were enrolled. After the intravenous administration of 740 MBq 99mTc-hexamethylpropylene amine oxime (HMPAO), all subjects underwent brain perfusion SPECT imaging applying AnyScan S Flex dual-head gamma camera (Mediso, Hungary). Using Philips Achieva 3T scanner brain resting-state functional MRI was also performed. The SPECT and MRI images were co-registered and transformed to the MNI152 atlas space so that data of the following standard volumes of interest (VOIs) could be obtained: frontal lobe, parietal lobe, temporal lobe, occipital lobe, limbic region, cingulate, insula, basal ganglia, cerebrum, limbic system and brain stem. Using the SPSS 25 statistical software package, general linear regression analysis, Student’s t-test, and Mann-Whitney U-test were applied for statistical analyses. Results: Multivariate linear analysis identified that BMI and age are significantly (p < 0.0001) associated with perfusion, and patient group was slightly above threshold (p = 0.0524). We also found that the presence of diabetes was an independent significant predictor of normalized regional brain perfusion only in the insula (p < 0.001). Other independent predictors of normalized regional brain perfusion were: age in the insula (p < 0.001) and in the limbic region (p < 0.01), and BMI in the brain stem (p < 0.01). Conclusions: Age and BMI proved to be general, and diabetes regional predictor of brain hypoperfusion. BMI appeared to be a novel factor affecting brain perfusion. In one specific region, the insula, we detected a difference between the obese and the diabetic group. These findings may be significant in the understanding of the development of cognitive impairment in metabolic diseases.

Aminopeptidase N (APN/CD13) plays an important role in neoangiogenic process in malignancies. Our previous studies have already shown that

Development of radiochemistry and hybrid technology resulted in a new era in the management of prostate cancer. Choline PET provides more sensitive and accurate diagnosis, and it can support the personalized, metastases-directed therapies. PSMA radioligands are used as theranostics worldwide but are not available in Hungary. 68Ga- or 18F-labelled molecules are excellent diagnostic agents which can detect the primary process and its metastases more sensitively than choline, especially at lower PSA levels. 177Lu-labelled PSMA ligand as a therapeutic pair of the diagnostic molecules can provide an effective therapeutic option in metastatic castration resistant prostate cancer. In this publication we review PSMA radioligand therapy (PRLT) in management of prostate cancer based on the recently published European guideline.

Quantifying tumour heterogeneity from [

ECG-gated SPECT myocardial perfusion imaging is usually acquired in supine position. However, some patients are not comfortable in this position for a variety of personal or medical reasons. Our aim was to investigate the effect of patient positioning on quantitative SPECT imaging results using normal supine database. 55 patients (mean age 58.5 ± 8.3 years) were enrolled in this prospective study. Each patient had a pair of ECG-gated stress SPECT myocardial perfusion images acquired on two gamma cameras: one in supine position and the other in upright sitting position. Left ventricular (LV) ejection fraction (EF), end-diastolic (ED), and end-systolic (ES) left ventricular volumes (V), LV mass, summed stress perfusion defect score (SSS), and total severity score (TSS) were calculated automatically relative to a supine normal reference database. There were no significant differences in LVEF using the two cameras (0.65 ± 0.08 vs. 0.66 ± 0.10; P > 0.1). However, EDV, ESV, and LV mass were significantly smaller in sitting position than in supine position (89 vs. 80 ml; 33 vs. 29 ml and 115 vs. 109 ml, respectively, all P

Dynamic inhalation scintigraphy (DIS) with technetium-99m-diethylenetriamine-pentaacetate aerosol is a useful nuclear medicine procedure for staging and monitoring the damage of alveolocapillary membrane. The e-cigarette is a new popular smoking device producing vapor from the nicotine solution. Many studies have shown that e-cigarettes appear to be safer than smoking, but there are still debates to what extent e-cigarettes are less harmful than smoking.In this prospective, self-controlled study, we compared DIS results among volunteers smoking an e-cigarette and their results after they returned to traditional cigarette smoking for a week.We included 24 healthy volunteers into this study who regularly used e-cigarette containing at least 10 mg nicotine/ml. We performed baseline DIS study in volunteers with e-cigarette smoking and then we asked them to return to traditional cigarette smoking for a week. Conventional respiration tests were also measured. We statistically analyzed the effect of traditional cigarette on clinical parameters and pulmonary clearance of the radiopharmacon.There was no significant change in the parameters of peak expiratory flow rate and Tiffeneau-Pinelli index respiration tests; forced vital capacity and forced expiratory volume in 1 s slightly decreased (P0.05), whereas the exhaled CO and COHb levels were significantly higher at traditional cigarette use (P0.0001), and increased in every case. The pulmonary clearance was significantly faster at traditional cigarette smoking compared with e-cigarette use (P0.0001).On the basis of our results, we suppose that e-cigarette smoking is less harmful to the lung function than a traditional cigarette, and it can be recommended to heavy smokers who are unable to stop smoking.

Purpose To measure tear clearance values in patients with meibomian gland dysfunction (MGD) with a dynamic nuclear medicine method, namely, dacryoscintigraphy (DSCI). Methods Twenty-four MGD patients and 24 healthy volunteers were examined. During DSCI one drop of a solution with 100 MBq/mL99mTc sodium pertechnetate was instilled with a micropipette into the lacrimal lake of both eyes. Measurements were performed according to a dynamic data acquisition protocol, which resulted in summed DSCI images. Data were also evaluated separately in special regions of interest (ROI), and consecutive time activity curves were created. Tear clearance (T½) values were calculated based on the activity curves. In addition, tear osmolarity measurements, tear breakup time (tBUT), and Schirmer I (STI) tests were performed prior to DSCI examination. Results The T½ values were 29.91 ± 11.61 min in MGD patients and 6.26 ± 1.5 min in healthy controls. Tear osmolarity parameters were 308 ± 9.41 mOsm/L and 288.9 ± 6.4 mOsm/L, tBUT values were 5.54 ± 2.73 s and 11.4 ± 2.7 s, while the STI test values were 6.17 ± 2.78 mm and 13.58 ± 3.8 mm, respectively. The differences were significant (p Conclusions Although the MGD patients’ lacrimal drainage systems were patent their tear clearance values were significantly higher than those of healthy volunteers, which may be caused by decreased drainage of tears from the eyes towards the nasal cavity. The understanding of new features regarding the altered physico-chemical characteristics of MGD tears has been augmented by the results of this study.

Objective: The objective of this study was to find the correlation between the severity of perfusion abnormality detected by scintigraphy and the FFR value, as well as the localization of a particular coronary lesion. On the basis of FFR values and the corresponding left ventricular segments, we proposed a combined index to aim for better correlation with myocardial ischemia than the FFR parameter alone. Methods: Twenty-eight patients (male: 22, female: 6, age 62±7.62) having FFR measurements and myocardial perfusion SPECT studies were enrolled in our retrospective analysis. FFR measurements on 36 vessels (20 LAD, 6 LCx, 10 RCA) with intermediate stenosis (40%-60%) were compared to the Tc-99m SestaMIBI myocardial perfusion SPECT studies. SPECT studies were performed before the invasive procedure in all cases. We introduced a new ischemic index, the left ventricular ischemic index (LVIi), by combining FFR values with the number of corresponding myocardial segments (N) [LVIi=N x (1-FFR)]. This index correlated with the regional myocardial perfusion defects identified on the scintigrams. A perfusion reversibility score of 2 or above was considered indicative of active ischemia (regional difference score: rDSc). For the statistical analysis, we used linear regression analysis and receiver operating characteristic (ROC) curve analysis to compare the different parameters. Results: A close linear relationship was found between the LVIi and rDSc values (p0.96 implies a clinically relevant stenotic lesion. In our opinion, FFR values, weighted with the corresponding left ventricular segments, should be taken into consideration for the best clinical decision-making.

Dilated cardiomyopathy is the main cause of heart transplantation. The etiology is unknown in almost half of the cases. Many cardiac specific antibodies have been identified till now which can cause decreased cardiac function, ventricular tachycardia or sudden heart death. The prognosis of DCM is poor despite the development of medical treatment. Immunoadsorption is hopeful since, with the removal of antibodies, cardiac function and NYHA class can improve and LVAD/heart transplantation-free survival can be prolonged. At the University of Debrecen, Faculty of Medicine, Department of Internal Medicine, Division of Angiology, Intensive Care and Therapeutic Apheresis Unit we performed the first immunoadsorption. Our patient was a 43-year-old man with idiopathic dilated cardiomyopathy, NYHA class IV, a heart transplantation candidate, whose cardiac specific antibody, type IgG was indentified by Western blot. Before the treatment he had ejection fraction of 18%. Discussing with his cardiologists we decided for immunoadsorption therapy. We performed 5 cycles on consecutive days in Intensive Care Unit. After 1 month we detected improvement in exercise capacity. We detected improvement in isovolemic contraction (from 465 mmHg/s to 575 mmHg/s), increased stroke volume (from 49 ml to 66 ml). After 3 months we repeated SPECT investigation which showed improvement in ejection fraction, from 18% to 32%. Orv Hetil. 2018; 159(13): 532-536.

FDG PET-CT is a global, noninvasive, sensitive method to determine the location and activity of inflammatory lesions. Segmental FDG uptake is proportional with immune cell infiltration of bowel. Our aim was to evaluate prospectively the role of PET in patients with active Crohn's disease (CD) before and after one year's biological therapy, and to compare simple endoscopic score for CD (SES-CD), CD activity index (CDAI) and global PET scores. We also analyzed the prognostic value of initial PET scores.Twelve patients were selected: six male/six female, ages between 18 and 39, average: 24 years, with CDAI values300.We scored the FDG uptake in the small intestine and the four colon segments (on a scale 0-3 for each), and summed them thus forming a global PET score. The scoring was based on the maximal standardized uptake value of the intestinal segment, related to the SUVmax of the liver (as a reference for normal tissue activity). The SES-CD, CDAI and global PET scores before and after treatment were statistically compared.There were significant changes in CDAI and SES-CD after therapy, PET scores improved only in patients' subgroup with high (4) initial PET score, indicating good prognosis of biological treatment. In active disease, PET was more informative than endoscopy to access the extent of the inflammation, and small intestine involvement.FDG PET-CT score is a promising, noninvasive complementary method in the staging, treatment planning and follow-up of CD. Limitation of the study is the small number of patients.

Decreased absolute lymphocyte/monocyte ratio (LMR) in peripheral blood has been reported as an unfavorable prognostic marker in Hodgkin lymphoma. We aimed to investigate whether combining LMR and interim PET/CT scan result (PET2) confers stronger prognostic value than PET2 alone. 121 HL patients were investigated. LMR was calculated from a blood sample taken at the time of diagnosis. PET2 was carried out after the second chemotherapy cycle. Survival was calculated using the Kaplan-Meier method and significance was determined by log-rank test. Effect of variants on survival results was examined using univariate and multivariate analyses. Best LMR cut-off value was determined by receiver operating characteristic (ROC) curve. Best LMR cut-off value was 2.11 in the case of our patients (LMR > 2.11: favorable, LMR ≤ 2.11: unfavorable). Overall and progression-free survivals (OS/PFS) were significantly worse both in lower LMR (≤ 2.11) (OS: P = 0.041, PFS: P = 0.044) and PET2 positive groups (OS: P < 0.001, PFS: P < 0.001). In PET2 positive patient group (n = 32) the low LMR result meant a significantly worse OS (0.030) and PFS (0.001). Both LMR and PET2 proved to be independent prognostic factors on multivariate analysis, and strengthened each other's effect.

BACKGROUND The Allen test is used worldwide for radial artery graft removal. The postoperative examination of our patients' hand function and circulation proved that beside the transient neurological complications chronic hand circulatory disorders may arise. AIM To develop a non-invasive method suitable for an objective evaluation of the hand's circulation to make it possible to use radial arteries safely for the revascularization of coronary arteries. METHODS We examined 35 patients. After selective compression of the radial and ulnar arteries of both hands, we injected 400 MBq (99m)Tc-HSA intravenously and acquired 240 images, each of 1 s. After 30 s we released the ulnar artery first, and after 120 s the radial artery, too. Then computer analysis was performed. RESULTS The patients could be divided into two groups. In the majority of them, releasing only the ulnar artery resulted in a good circulation of the fingers. It meant that the time-activity curve rapidly reached its maximum, and the activity did not change even after releasing the radial artery. In a smaller proportion of the patients the activity of the fingers increased only slowly, and did not reach a plateau even after 30 s. Following the release of the radial artery a further increase in the activity could be observed. We assume that the latter patient group is at risk of consequent circulatory disorder of the fingers after the removal of the radial artery, whereas in the former group the artery could be removed safely. CONCLUSIONS Hand perfusion with (99m)Tc-HSA is useful in patients selected for coronary bypass operations, so we recommend the introduction of this method as a routine examination before the removal of the radial artery in patients with an abnormal Allen test.

Aim To look for the frequency of oesophageal dysfunction using radionuclide oesophageal transit scintigraphy in 145 patients with undifferentiated connective tissue disease (UCTD); to seek the correlation between the clinical/laboratory data and scintigraphic alterations; and to determine predictive value of radionuclide oesophageal transit scintigraphy for evolution to established connective tissue disease (CTD). Method One hundred and forty-five patients with UCTD were examined by 9 9 m Tc-DTPA oesophageal transit scintigraphy. The intraoesophageal transport of the radiopharmaceutical was followed and imaged by a gamma camera, a series of 128 × 128 images were stored and evaluated. The correlation between the scintigraphic data and clinical and laboratory parameters was analysed statistically. Results Unequivocally positive scintigraphy, indicative of motor abnormality was found in 46% of patients (66), 71% (47) of whom were totally asymptomatic. Significant correlation was found between the presence and severity of scintigraphic alterations and antinuclear antibodies, the anti-β2GPI, IgM, IgG, the aCL antibody positivity, and the skin symptoms. Scintigraphic positivity was significantly more frequent in patients evolving to definitive CTD (P=0.0178), and abnormal scan predisposed to transition into the definitive CTD (odds ratio, 2.292; Cl, 1.610-4.525). Its cumulative positive predictive value was found to be 43% and cumulative negative predictive value 73% with regard to the development of a definitive CTD. Conclusion Our results show that scintigraphic alterations together with clinical and laboratory alterations can help the clinician in the prediction of final outcome.

Background The immunosuppressive treatment of Graves' orbitopathy (GO) influences the course of the disease in the early, active, retrobulbar inflammatory phase (active GO), which cannot be detected by direct clinical examination. Aim To evaluate the clinical effectiveness of a newly developed method for the detection of intraorbital inflammatory activity in patients suffering from Graves' orbitopathy, utilizing a four-headed single photon emission tomograph (SPET) camera and 9 9 m Tc-diethylenetriamine pentaacetic acid ( 9 9 m Tc-DTPA). Methods The magnetic resonance imaging (MRI) T2 relaxation time score, as a measure of ongoing orbital inflammation (reference method), was compared with the uptake activities (UA) of 9 9 m Tc-DTPA orbital SPET and the more specific 9 9 m Tc-Neospect ( 9 9 m Tc-depreotide) SPET, as well as the clinical activity scores (CAS), in 21 patients (42 orbits). Results By visual inspection, the 'eye SPET' frames of patients suffering from active GO could be easily distinguished from those with inactive GO. Although the distributions of the two radiopharmaceuticals were mildly different, the information obtained was essentially the same. The MRI activity scores correlated well with both 9 9 m Tc-DTPA and 9 9 m Tc-depreotide UA. The mean 9 9 m Tc-DTPA UA value of 25 inactive GO orbits was (6.55 ′ 1.4) x 10 - 6 ID cm - 3 (where ID is the injected dose); the values of the active GO orbits (12 orbits with an MRI score of 1 and five orbits with an MRI score of 2) were significantly higher: (8.87 ′ 1.63) × 10 - 6 and (10.36 ′ 1.60) × 10 - 6 ID cm - 3 , respectively. Similar differences were observed for the 9 9 m Tc-depreotide UA values: the averages in the inactive and active groups with MRI scores of 1 and 2 were (5.23 ′ 1.23) × 10 - 6 , (7.69 ′ 2.24) × 10 - 6 and (10.92 ′ 3.85) x 10 - 6 ID . cm - 3 , respectively. The 9 9 m Tc-DTPA accumulation pattern in the orbital region of active GO patients was similar to that of the more specific 9 9 m Tc-depreotide. There was a good correlation (r=0.71, P

Currently available methods for the estimation of disease activity in the orbits of patients with Graves' ophthalmopathy (GO) have the disadvantages of being either expensive or time consuming. The aim of this study was to develop a quick, reliable method using Tc labelled diethylenetriaminepentaacetic acid (DTPA) and four-headed single photon emission computed tomography (SPECT) for this purpose. The theoretical basis of the method is that the high capillarization and oedema in the orbit may be reflected on Tc-DTPA images in GO. SPECT data of 28 orbits of 14 patients with GO were compared with magnetic resonance imaging (MRI) T2 relaxation time scores. Based on the number of 'active' muscles with T2 relaxation times of more than 70 ms in a given orbit, an MRI score of 0 (no active muscle) to 4 (all rectus muscles active) was assigned to the orbit. With MRI, 18 orbits were inactive, and 10 were active. Thirty minutes after the intravenous administration of 7 MBq.kg Tc-DTPA, 128 projections were acquired by a four-headed SPECT. On the sum of six transaxial slices containing the entire bulbar region of the skull, a triangle-like region of interest (ROI) was drawn (OR ROI). This ROI was 'slipped' to the right temporal region of the brain as reference site (B ROI). The count ratios of OR/B were calculated and compared to MRI score values. In the group of 18 inactive orbits (an MRI score of zero on both sides), in the transaxial plane, the mean OR/B value was 6.4+/-1.17, and in the group of 10 active orbits (an MRI score of 1-3) 8.30+/-2.08, the difference being significant (P

The aim of this study was to test the applicability of 99m Tc-hexamethylpropylene amine oxime ( 99m Tc-HMPAO) labelled leukocyte joint scintigraphy in the assessment of disease activity in 21 patients with rheumatoid arthritis, and to compare leukocyte scintigraphy with the Disease Activity Score (DAS), a validated activity index developed by the European League Against Rheumatism (EULAR). Twenty-one patients with rheumatoid arthritis were investigated by using 99m Tc-HMPAO labelled leukocyte joint scintigraphy. The clinical and laboratory data were recorded, and the DAS was calculated and compared with the scintigraphic results in each case. A relatively high DAS score (4.71 ± 1.07) was found in the majority of patients. The degree of accumulation of 99m Tc-HMPAO leukocytes showed no correlation with a patient's age, gender, duration of disease, use of disease modifying anti-rheumatic drugs (DMARDs), visual analogue scale (VAS), Richie index, DAS, or any laboratory parameters. In contrast, a significant correlation was found between the global regional accumulation of the labelled leukocytes of the hands and feet, and the swollen-joint count. It is concluded that radiolabelled leukocyte scintigraphy could become one of the promising methods in the assessment of disease activity in patients with rheumatoid arthritis.

11C-choline has been used in the diagnosis and follow-up of patients with prostate cancer for years. Choline PET/CT has been available in human care since March, 2014 in our country. Unfortunately this examination has not been reimbursed by the National Health Insurance so far. We retrospectively analysed and assessed the results of 40 patients who underwent 11C-choline PET/CT on the basis of previous literature. As our study group was heterogeneous statistical analysis was not performed.A 11C-kolin-PET-et már több éve sikeresen alkalmazzák a prosztatarák diagnosztikájában és a betegkövetésben. Hazánkban 2014 márciusától van lehetõségünk 11C-kolin-PET/CT-vizsgálatokat végezni a humán betegellátásban, egyelõre csak magántérítéses formában. A jelen közleményben 40, 11C-kolin-PET/CT-vizsgálatra került férfibeteg adatait dolgoztuk fel retrospektíven és értékeltük az irodalom tükrében. Mivel a betegcsoport heterogén volt, csak esettanulmányt végeztünk, statisztikai analízis nem történt.

Dynamic imaging of the inflow of technetium-99m hexamethylpropylene amine oxime (HMPAO) to the brain has been proved to allow estimation of the hemispherical cerebral blood flow (CBF) using the Patlak plot. In this study, we compared the hemispherical CBF (in ml/min/100 g) of different patient groups. A total of 25 patients (comprising 13 with migraine and 12 scheduled for endarterectomy owing to angiographically confirmed severe stenosis of the internal carotid artery on at least one side) underwent baseline and acetazolamide 99mTc-HMPAO brain perfusion studies. In addition, acetazolamide 99mTc-HMPAO studies were performed in 12 healthy subjects (no baseline study was performed for ethical reasons.) Dynamic studies were acquired by means of a dual-detector gamma camera with a large field of view (HELIX, Elscint). Special difference images were created to make definition of the aortic arch and hemispherical brain regions easier and more reproducible. A semi-automatic method was developed to determine the transit time from the aorta to the brain, making the generation of the Patlak plot even more robust. The baseline CBF values did not significantly depend on the disease (P0.1), whereas the CBF values obtained after acetazolamide provocation did do so (ANOVA, P0.001). Patients suffering from migraine showed a significant increase in global CBF values after acetazolamide provocation (paired t test, P0.05), but we could not find any effect of the provocation in patients awaiting carotid endarterectomy, indicating a lack of cerebrovascular reserve capacity. Comparison of the results of the acetazolamide study in patients and the control group revealed the CBF values to be significantly lower in patients with carotid stenosis (two-sample t-test, P0.001), but not in those with migraine (P0.1). In summary, using quantitative analysis of 99mTc-HMPAO brain studies we could objectively compare the CBF of patients suffering from different diseases. Especially the CBF values obtained after acetazolamide provocation permitted effective differentiation of disease states. The quantitative results may be of assistance in therapy planning, e.g. in selection of the correct operative technique.

A non-invasive nuclear medicine technique was developed to screen patients with painful hands so as to separate patients with a normal from those with an abnormal microcirculation of the hands in different clinical conditions. Such a technique is important, as the other methods available are either subjective or rather complicated. The study population consisted of 10 healthy individuals, 23 patients with Raynaud's syndrome and 15 patients with mixed connective tissue disease (MCTD). Sixty gamma-camera images of the hands (1 s each) were recorded after a bolus injection of 99Tcm-DTPA via a dorsal foot vein. Regions of interest were drawn on the summed images around the fingers and the palmar region. The fingers-to-palm ratio was then calculated from the total counts inside these regions of interest separately for each hand. The mean fingers-to-palm ratio was 0.94+/-0.18 (0.71-1.25) for the healthy group, 0.57+/-0.22 (0.21+/-1.11) for the MCTD group and 0.40+/-0.14 (0.18-0.77) for the Raynaud's patients. Analysis of variance showed these differences to be highly significant (P < 0.001). There were also significant differences between 6 MCTD patients in an active (mean 0.48) and nine patients in an inactive (mean 0.66) clinical state (two-sample t-test: P < 0.05). There were no significant differences between the fingers-to-palm ratios of the left and right hands of the same patients (one-sample t-test). Of the 23 primary Raynaud's patients, capillary microscopic data were pathological in only eight (34%). We conclude that our method is able to differentiate between patients with normal and those with abnormal microcirculation of the hands. Although measurement of the fingers-to-palm ratio is not a specific method, it is useful both for staging and in the follow-up of patients.

The aim of the study was to assess sensitivity and specificity of FDG-PET/CT in different forms of childhood cancer. We retrospectively evaluated the results dedicated of 162 FDG-PET/CT examinations of 86 children treated with: Hodgkin lymphoma (HL; n = 31), non-Hodgkin lymphoma (NHL; n = 30) and other high grade solid tumors (n = 25). Patients were admitted and treated in two departments of pediatric hematology and oncology in Hungary. FDG-PET/CT was performed for staging (n = 25) and for posttreatment evaluation (n = 137). Imaging was performed in three FDG-PET/CT Laboratories, using dedicated PET/CT scanners. False positive results were defined as resolution or absence of disease progression over at least 1 year on FDG-PET/CT scans without any intervention. In some cases histopathological evaluation of suspicious lesions was performed. Fals negative results were defined as negative FDG-PET/CT results in case of active malignancy. Positive predictive values (PPV) and negative predictive values (NPV) were calculated. NPV was 100 %. The highest PPV was observed in high grade solid tumors (81 %), followed by HL (65 %) and NHL (61 %). There was a major difference of PPV in different histological types of HL (50 % in HL of mixed-cellularity subtype, 90 % in nodular sclerosing, and 100 % in lymphocyte-rich and lymphocyte depleted HL). We treated one patient with nodular lymphocyte predominant HL, who had 5 false positive FDG-PET/CT results. PPV of T- and B-lineage NHL were similar (60 % and 62 %, respectively). We observed an interesting difference of PPV in different stages of HL and NHL. In HL PPV was higher in early than in advanced disease forms: 66 % in stage II HL and 60 % in stage III HL, whereas there was an inverse relationship between PPV and disease stages in NHL 0 % in stage I and II patients, 67 % in stage III and 100 % in stage IV patients. PPV was lower in males (54 %) than in females (65 %). PPV were 64 % vs. 58 % in patients under vs. over 10 years of age. Negative FDG-PET/CT results during follow-up reliably predict the absence of malignancy. Positive FDG-PET/CT scan results in general have a low PPV. The relatively high PPV in patients with histologically proven high grade solid tumors, advanced stages of NHL and with nodular sclerosing, lymphocyte-rich and lymphocyte depleted subtypes of HL warrant a confirmation by biopsy, whereas the watch-and-wait approach can be used in other forms of childhood cancer patients with a positive FDG-PET/CT result in course of follow-up examinations.

Epiphora, an abnormal overflow of tears, is commonly caused by tear drainage system anomalies including nasolacrimal duct obstruction. To assess morphologic abnormalities, dacryocystography by CT is used when CT contrast material is syringed into the lacrimal drainage system. To evaluate the function of the system, dacryoscintigraphy is the most readily available noninvasive method. In the case presented, a 43-year-old man was referred to our clinic with an 8 months' history of indefinite left side epiphora. After performing dacryoscintigraphy, we acquired SPECT/CT images during dacryocystography by CT to establish the surgical indication.

The fever of unknown origin from time to time constitutes a serious clinical problem and nearly all diagnostic methods are involved to discover urgently its cause. According to literature data (18)F-fluoro-deoxyglucose PET/CT was successful in 25-70% of cases even in patients without any positive findings with conventional diagnostic techniques. The Hungarian National Health Fund does not include fever of unknown origin in the list of reimbursed (18)F-fluoro-deoxyglucose PET/CT indications. The authors try to illustrate the clinical problem with this case report. Fever of unknown origin persisted in a patient for a year, but conventional diagnostic procedures were unsuccessful to find the cause of the fever. Finally, (18)F-fluoro-deoxyglucose PET/CT indicated a metabolically active focus between the pancreas tail and the spleen. After a long-lasting antibiotic therapy the patient became symptomfree.

We present a novel detection and classification method to process SPECT-CT images representing breast and prostate lymph nodes. Lymph nodes are those nodes that are near the primer tumor and may become cancerous in time, hence their early detection is a key factor for the successful treatment of the patient. Prior methods focus on the visual aid to manually detect the lymph nodes which still makes the process time-consuming. Other solutions segment the lymph nodes only on CT, where the small lymph nodes may not be located accurately. Our solution processed both SPECT and CT data to provide an accurate classification of all SPECT hot spots. The method has been validated on a huge amount of medical data. Results show that our method is a very effective tool to support physicians working with related images in the field of nuclear medicine.

A 32-year-old male patient was diagnosed with nodular lymphocyte-predominant Hodgkin lymphoma. Staging FDG PET-CT detected a large right axillary lymph node conglomerate and splenic manifestation. Interim PET-CT following two cycles of ABVD chemotherapy revealed good metabolic response with the exception of a single axillary lymph node. A second "interim" PET-CT after two further cycles showed a similar result. A biopsy of the metabolically active non-palpable lymph node was performed using radioguided occult lesion localization (ROLL) with ultrasound guidance. The lymph node was successfully removed by minimally invasive surgery. Histological evaluation of the lymph node revealed a T cell-rich diffuse large B cell lymphoma. Based on this finding, a more aggressive treatment regimen followed by high dose chemotherapy with autologous stem cell rescue was adopted. To our knowledge, this is the first report of a lymphoma case in which the ROLL method was used in the radioguided biopsy of a chemoresistant lymph node detected by interim FDG PET-CT.

Although macrovascular complications are typical for type 2 diabetes mellitus (T2DM), cerebral microvascular damage develops both in type 1 diabetes mellitus (T1DM) and T2DM. Color Doppler ultrasound is widely used for the examination of large- and medium-sized arteries, whereas SPECT and MRI are capable of identifying disturbances in the circulation of microvessels. Former studies using semiquantitative methods showed reduced reactivity and reserve capacity of cerebral vessels in both T1DM and T2DM patients. Our aim was to investigate whether there was any difference in the effects of the 2 types of diabetes mellitus on the global or regional cerebral blood flow, influenced by microvascular damage.In our study, the circulation and reserve capacity of cerebral arteries was examined using (99m)Tc-hexamethylpropylene amine oxime SPECT. A total of 17 individuals with T1DM and 43 individuals with T2DM were involved in the study.Both basal and acetazolamide-challenged brain circulation were significantly lower in T2DM patients than in T1DM patients. We did not find a significant difference in the reserve capacity. However, the circulation of the frontal and occipital lobes changed differently in the 2 groups. The ratio of the circulation of the frontal and occipital lobes was significantly reduced both in basal and in acetazolamide-stimulated states in T2DM patients, independently of age (P0.0005 and P0.017), showing a greater relative decrease in the circulation of the frontal lobe in T2DM patients.There was a significant association between basal brain circulation and age, body mass index, and high-density lipoprotein (HDL), whereas acetazolamide-stimulated circulation showed a significant association with serum triglyceride and HDL.

BACKGROUND Data about biochemical abnormalities (catecholamines) during vasovagal syncope (VVS) are available, but adrenergic myocardial structural damage may be hypothesized as well. AIM To study the global and regional adrenergic myocardial innervations in patients with VVS that was shown by head-up tilt table testing. PATIENTS AND METHODS Fifteen adult patients with VVS were studied. The age of patients was 44+/-18 years (17-73), nine were female and six were male. According to the tilt test results, five patients had cardioinhibition, six patients had vasodepressor syncope and four patients suffered from mixed-type VVS. Ischemic heart diseases were excluded by normal Tc-MIBI rest-stress dipyridamol single-photon emission computed tomography (SPECT) results. A control group was formed from six healthy adult volunteers. To investigate cardiac sympathetic innervations 250-370 MBq iodine-123 meta-iodobenzylguanidine (I-MIBG) was used. Fifteen minutes after the intravenous administration of I-MIBG early, and 2-3 h later, delayed planar myocardial and tomographic (SPECT) scintigraphies were performed. The heart-to-mediastinum count ratio (H/M) was calculated for both early and delayed images, together with the decay-corrected change rates. The regional I-MIBG uptake was visualized on SPECT slices and polar map images. The regional uptake was considered pathological below 50% compared with normal uptake sites. RESULTS Delayed H/M ratios significantly depended on group (analysis of variance: P=0.005), whereas early H/M values did not. Although the decay-corrected myocardial MIBG uptake increased in time in controls, less wash-in or even wash-out could be observed in the VVS groups; however, difference from the controls was significant only in the vasodepressor group (Dunnett's t-test: P

Primary Raynaud's disease is generally a disease of younger females; however, there are cases where symptoms present over the age of 40. These cases are described as late onset. In our current prospective study we compared the characteristics of early and late onset types of primary Raynaud's in 127 patients. In addition to the collection of medical records, we performed capillary-microscopy and hand perfusion scintigraphy using Tc-99 m DTPA to evaluate the microcirculation of each patient's fingers. Regarding the spectrum of the capillary-microscopic findings, we did not find any significant difference between the early and late onset forms. However, in hand perfusion examinations done using Tc-99 m DTPA, we measured a significantly lower finger/palm ratio (FPR) in the early onset group of patients. We also observed a correlation between the duration of the disease and the FPR, as well as between the age and FPR. Longer disease duration resulted in a significantly lower FPR. On the basis of our results, we believe that late onset Raynaud's should be treated as a separate entity. Due to its different characteristics found on examination and follow-up of our patients, functional hand perfusion examination should be recommended independently of the age-related characteristics of the disease.

Currently there is no ideal imaging technique which could estimate the degree of inflammation in thyroid eye disease.A new, rapid and cost-effective method, using 99mTc-labelled DTPA and 4-headed SPECT, was developed which is able to diagnose inflammatory activity in patients with endocrine orbitopathy (EOP).The MRI T2 relaxation time was used as reference. Comparative orbital SPECT with the more specific 99mTc-Neospect (depreotide) was also performed in the same patients.Visual evaluation of orbital SPECT frames of patients suffering from active EOP could be easily distinguished from inactive EOP patients'. Despite the supposedly different characteristics of the two tested radiopharmaceuticals, there was essentially no difference between their accumulation in the orbit and the information obtained. The MRI activity scores correlated well with 99mTc-DTPA activity uptake (AU). The mean AU value in patients with inactive EOP was 6.26 +/- 1.6 10(-6) ID/cm3, while in active EOP 10.78 +/- 0.61 10(-6) ID/cm3, significantly higher. The 99mTc-DTPA accumulation in the orbital region in active disease was similar to that of depreotide. There was a good correlation (r = 0.91, P0.0001) between the two methods.The authors concluded that 99mTc-DTPA orbital SPECT is a potentially useful method, which--after initial clinical and MRI staging--gives useful quantitative estimation of disease activity in endocrine orbitopathy. It may provide important visual and quantitative information during the follow up of patients.

The authors have analyzed and compared the results of the 99mTc-ECD-SPECT and FDG-PET examinations, performed in alert state, of 12 children suffering from infantile (9 subjects) or atypical (3 subjects) autism. In addition to frontally increased FDG metabolism, a decreased blood flow with left-sided dominance was found bifrontally and bitemporally in the infantile form (perfusion-metabolism mismatch). The regional differences in cortical FDG uptake were not significant in atypical autism, although both the blood flow and the metabolism of the thalami were decreased. Based on the results, the authors suggest that, beyond the usually inconclusive structural (CT or MR) examinations, cerebral blood flow SPECT and metabolic FDG-PET investigations may be useful in classifying the disease.