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Nevrodegenerativne bolezni možganov, ki se klinično izrazijo kot demenca ali parkinsonizem, postajajo s staranjem prebivalstva vse pogostejše. Zgodnja in pravilna diagnoza je pomembna zaradi izključevanja ozdravljivih vzrokov, ustreznega simptomatskega zdravljenja, socialnih ukrepov in vključevanja bolnikov v klinične raziskave. Dokončno diagnozo večine nevrodegenerativnih bolezni možganov lahko postavimo le na podlagi patohistološkega vzorca možganovine. Za živa so nam v veliko pomoč funkcijske nuklearnomedicinske preiskave, s katerimi lahko prikažemo spremenjeno regionalno presnovo možganov, motnje na nivoju nevrotransmiterskih sistemov in patomorfološki substrat bolezni – kopičenje patoloških beljakovin. Glede na značilne spremembe regionalne presnove možganov, ki jih preučujemo s pozitronsko emisijsko tomografijo (PET) možganov z uporabo z radioaktivnim fluorom (18F) označene deoksiglukoze, lahko razlikujemo med alzheimerjevo boleznijo, demenco z lewyjevimi telesci, frontotemporalno demenco in redkejšimi vzroki kognitivnega upada ter med parkinsonovo boleznijo in drugimi nevrodegenerativnimi parkinsonizmi. Z ugotavljanjem integritete dopaminergičnega sistema (npr. scintigrafijo dopaminskega prenašalca; DaTSCAN) lahko razlikujemo med nevrodegenerativnimi parkinsonizmi in drugimi možnimi vzroki težav. Amiloidni PET možganov nam prikaže prisotnost in značilno razporeditev prekomernega kopičenja amiloida pri bolnikih z alzheimerjevo boleznijo že pred pojavom kliničnih znakov bolezni. V prispevku predstavljamo nuklearno medicinske preiskave, obravnavamo indikacije in značilne spremembe ter omejitve teh preiskav v diagnostiki nevrodegenerativnih bolezni možganov.

Background Striatal dopamine deficiency and metabolic changes are well-known phenomena in dementia with Lewy bodies and can be quantified in vivo by I-123-Ioflupane brain single-photon emission computed tomography of dopamine transporter and F-18-fluorodesoxyglucose PET. However, the linkage between both biomarkers is ill-understood. Objective We used the hitherto largest study cohort of combined imaging from the European consortium to elucidate the role of both biomarkers in the pathophysiological course of dementia with Lewy bodies. Methods We compared striatal dopamine deficiency and glucose metabolism of 84 dementia with Lewy body patients and comparable healthy controls. After normalization of data, we tested their correlation by region-of-interest-based and voxel-based methods, controlled for study center, age, sex, education, and current cognitive impairment. Metabolic connectivity was analyzed by inter-region coefficients stratified by dopamine deficiency and compared to healthy controls. Results There was an inverse relationship between striatal dopamine availability and relative glucose hypermetabolism, pronounced in the basal ganglia and in limbic regions. With increasing dopamine deficiency, metabolic connectivity showed strong deteriorations in distinct brain regions implicated in disease symptoms, with greatest disruptions in the basal ganglia and limbic system, coincident with the pattern of relative hypermetabolism. Conclusions Relative glucose hypermetabolism and disturbed metabolic connectivity of limbic and basal ganglia circuits are metabolic correlates of dopamine deficiency in dementia with Lewy bodies. Identification of specific metabolic network alterations in patients with early dopamine deficiency may serve as an additional supporting biomarker for timely diagnosis of dementia with Lewy bodies. (c) 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society. Funding Agencies|Velox Foundation [project 1123]; Schweizerischer Nationalfonds zur Forderung der Wissenschaftlichen Forschung [SNF 320030_169876]

To evaluate the reproducibility of the expression of Parkinson's Disease Related Pattern (PDRP) across multiple sets of 18F-FDG-PET brain images reconstructed with different reconstruction algorithms.18F-FDG-PET brain imaging was performed in two independent cohorts of Parkinson's disease (PD) patients and normal controls (NC). Slovenian cohort (20 PD patients, 20 NC) was scanned with Siemens Biograph mCT camera and reconstructed using FBP, FBP+TOF, OSEM, OSEM+TOF, OSEM+PSF and OSEM+PSF+TOF. American Cohort (20 PD patients, 7 NC) was scanned with GE Advance camera and reconstructed using 3DRP, FORE-FBP and FORE-Iterative. Expressions of two previously-validated PDRP patterns (PDRP-Slovenia and PDRP-USA) were calculated. We compared the ability of PDRP to discriminate PD patients from NC, differences and correlation between the corresponding subject scores and ROC analysis results across the different reconstruction algorithms.The expression of PDRP-Slovenia and PDRP-USA networks was significantly elevated in PD patients compared to NC (p0.0001), regardless of reconstruction algorithms. PDRP expression strongly correlated between all studied algorithms and the reference algorithm (r⩾0.993, p0.0001). Average differences in the PDRP expression among different algorithms varied within 0.73 and 0.08 of the reference value for PDRP-Slovenia and PDRP-USA, respectively. ROC analysis confirmed high similarity in sensitivity, specificity and AUC among all studied reconstruction algorithms.These results show that the expression of PDRP is reproducible across a variety of reconstruction algorithms of 18F-FDG-PET brain images. PDRP is capable of providing a robust metabolic biomarker of PD for multicenter 18F-FDG-PET images acquired in the context of differential diagnosis or clinical trials.

Differentiation among parkinsonian syndromes may be clinically challenging, especially at early disease stages. In this study, we used 18F-FDG-PET brain imaging combined with an automated image classification algorithm to classify parkinsonian patients as Parkinson’s disease (PD) or as an atypical parkinsonian syndrome (APS) at the time when the clinical diagnosis was still uncertain. In addition to validating the algorithm, we assessed its utility in a “real-life” clinical setting. One hundred thirty-seven parkinsonian patients with uncertain clinical diagnosis underwent 18F-FDG-PET and were classified using an automated image-based algorithm. For 66 patients in cohort A, the algorithm-based diagnoses were compared with their final clinical diagnoses, which were the gold standard for cohort A and were made 2.2 ± 1.1 years (mean ± SD) later by a movement disorder specialist. Seventy-one patients in cohort B were diagnosed by general neurologists, not strictly following diagnostic criteria, 2.5 ± 1.6 years after imaging. The clinical diagnoses were compared with the algorithm-based ones, which were considered the gold standard for cohort B. Image-based automated classification of cohort A resulted in 86.0% sensitivity, 92.3% specificity, 97.4% positive predictive value (PPV), and 66.7% negative predictive value (NPV) for PD, and 84.6% sensitivity, 97.7% specificity, 91.7% PPV, and 95.5% NPV for APS. In cohort B, general neurologists achieved 94.7% sensitivity, 83.3% specificity, 81.8% PPV, and 95.2% NPV for PD, while 88.2%, 76.9%, 71.4%, and 90.9% for APS. The image-based algorithm had a high specificity and the predictive values in classifying patients before a final clinical diagnosis was reached by a specialist. Our data suggest that it may improve the diagnostic accuracy by 10–15% in PD and 20% in APS when a movement disorder specialist is not easily available.

A 76-year-old man with prostate cancer underwent an 18F-choline PET/CT scan for detecting the presence of possible metastatic disease. The patient had normal serum parathormone (PTH) level with normal serum calcium and biochemistry.

V prispevku so predstavljena priporočila za obravnavo bolnikov z limfedemom. Prikazana je klinična slika, diagnosticiranje in različni načini obravnave.

Background. Incidental 18F-FDG uptake in the thyroid on PET-CT examinations represents a diagnostic challenge. The maximal standardized uptake value (SUVmax) is one possible parameter that can help in distinguishing between benign and malignant thyroid PET lesions. Patients and methods. We retrospectively evaluated 18F-FDG PET-CT examinations of 5,911 patients performed at two different medical centres from 2010 to 2011. If pathologically increased activity was accidentally detected in the thyroid, the SUVmax of the thyroid lesion was calculated. Patients with incidental 18F-FDG uptake in the thyroid were instructed to visit a thyroidologist, who performed further investigation including fine needle aspiration cytology (FNAC) if needed. Lesions deemed suspicious after FNAC were referred for surgery. Results. Incidental 18F-FDG uptake in the thyroid was found in 3.89% ― in 230 out of 5,911 patients investigated on PET-CT. Malignant thyroid lesions (represented with focal thyroid uptake) were detected in 10 of 66 patients (in 15.2%). In the first medical centre the SUVmax of 36 benign lesions was 5.6 ± 2.8 compared to 15.8 ± 9.2 of 5 malignant lesions (p < 0.001). In the second centre the SUVmax of 20 benign lesions was 3.7 ± 2.2 compared to 5.1 ± 2.3 of 5 malignant lesions (p = 0.217). All 29 further investigated diffuse thyroid lesions were benign. Conclusions. Incidental 18F-FDG uptake in the thyroid was found in 3.89% of patients who had a PET-CT examination. Only focal thyroid uptake represented a malignant lesion in our study ― in 15.2% of all focal thyroid lesions. SUVmax should only serve as one of several parameters that alert the clinician on the possibility of thyroid malignancy.

PURPOSE To evaluate reproducibility of diuretic renography, performed according to current guidelines in adult and pediatric patient populations. MATERIALS AND METHODS Fifty adult and 50 pediatric renograms were processed twice by each of three observers. For differential renal function (DRF) assessment, intraclass correlation coefficient (ICC), standard deviation of DRF calculation and the repeatability parameter were calculated. For drainage assessment, ICC was calculated. Intraobserver and interobserver analysis was performed for both parameters. Patient groups and subgroups (age, DRF asymmetry, drainage) were compared by analysis of variance. RESULTS Interobserver analysis, adult patient group: DRF-repeatability 4.20%, ICC 0.99. Drainage-ICC 0.92/1.00 (left/right kidney). Pediatric patient group: DRF-repeatability 7.80%, ICC 0.97. Drainage-ICC 0.93/0.85 (left/right kidney). Intraobserver analysis, adult patient group: DRF-repeatability 2.61%, ICC 0.99. Drainage-ICC 0.92/1.00 (left/right kidney). Pediatric patient group: DRF-repeatability 4.76%, ICC 0.98. Drainage-ICC 0.92/0.88 (left/right kidney). Highest repeatability and thus highest DRF dispersion was found in the subgroup of patients with poor/impaired kidney drainage and reduced DRF (repeatability 11.3%, analysis of variance, P

tangles, neuritic and diffuse plaques.QSMmaps were created with a magnitude-weighted L1-regularization algorithm.The susceptibility maps from all participants were spatially normalized by non-linearly registering the susceptibility maps to a template using the Automated Registration Toolbox. The putamen and caudate were outlined on the template and the outlines were superimposed onto the spatially transformed susceptibility maps. Themedian susceptibility value in each regionwas extracted for each participant. Linear regression was used in each region to investigate the link between susceptibility values and the composite measure of global AD pathology, controlling for age at death, sex, and postmortem interval to imaging. Statistical significance was set at p

A 57-year-old male was admitted with suspected acute coronary syndrome. He reported experiencing moderate chest pain when walking during the day prior to admission, but had very prominent ST segment elevations in the precordial electrocardiography (EKG) leads. A physical examination revealed remarkable severe kyphoscoliosis with chest deformity. The patient's cardiac troponin levels remained normal, while cardiac ultrasound and magnetic resonance imaging of the chest confirmed hypertrophic cardiomyopathy (HCM) with severe thickening of the interventricular septum. Ischemic heart disease was ruled out by myocardial perfusion imaging with (99m)Tc-MIBI during rest and dipyridamole-induced stress without showing irreversible or reversible myocardial ischemia. Our diagnosis was that the chest pain was noncardiac in origin and that the pronounced ST segment elevations in the precordial EKG leads reflected the severely hypertrophic interventricular septum through the normally thick left ventricular free wall. The patient's chest wall deformity brought his septum and the ventricular free wall nearly parallel to the left side of the chest wall, allowing for complete expression of the reciprocal EKG pattern of septal hypertrophy. We suggest that EKG findings should always be interpreted with the chest wall shape being kept in mind.

Background. In current clinical practice lung scintigraphy is mainly used to exclude pulmonary embolism (PE). Modified diagnostic criteria for planar lung scintigraphy are considered, as newer scitigraphic methods, especially single photon emission computed tomography (SPECT) are becoming more popular. Patients and methods. Data of 98 outpatients who underwent planar ventilation/perfusion (V/Q) scintigraphy and 49 outpatients who underwent V/Q SPECT from the emergency department (ED) were retrospectively collected. Planar V/Q images were interpreted according to 0.5 segment mismatch criteria and revised PIOPED II criteria and perfusion scans according to PISA-PED criteria. V/Q SPECT images were interpreted according to the criteria suggested in EANM guidelines. Final diagnosis of PE was based on the clinical decision of an attending physician and evaluation of a 12 months follow-up period. Results. Using 0.5 segment mismatch criteria and revised PIOPED II, planar V/Q scans were diagnostic in 93% and 84% of cases, respectively. Among the diagnostic planar scans readings specificity for 0.5 segment mismatch criteria was 98%, and 99% for revised PIOPED II criteria. V/Q SPECT showed a sensitivity of 100% and a specificity of 98%, without any non-diagnostic cases. In patients with low pretest probability for PE, planar V/Q scans assessed by 0.5 segment mismatch criteria were diagnostic in 92%, and in 85% using revised PIOPED II criteria, while perfusion scintigraphy without ventilation scans was diagnostic in 80%. Conclusions. Lung scintigraphy yielded diagnostically definitive results and is reliable in ruling out PE in patients from ED. V/Q SPECT has excellent specificity and sensitivity without any non-diagnostic results. Percentage of nondiagnostic results in planar lung scintigraphy is considerably smaller when 0.5 segment mismatch criteria instead of revised PIOPED II criteria are used. Diagnostic value of perfusion scintigraphy according to PISA-PED criteria is inferior to combined V/Q scintigraphy; the difference is evident especially in patients with low pretest probability for PE.

Very limited data are available in the literature on the doses of unwanted radiation that patients receive following treatment with radiosynoviorthesis (RSO).The aim of this study was to assess the radiation exposure after RSO with (186)Re colloid in hemophiliacs.This study involved 12 hemophiliacs who were treated for hemophilic joint disease with 14 RSOs by using (186)Re colloid. Whole-body scintigrams were performed 1, 6, and 24 hours and 3 and 7 days after RSO. Measurements, using a whole-body counter, were done immediately after scintigraphy, with the treated joint protected with a lead shield. The cumulative activity of (186)Re in the body and in the lymph nodes was calculated. The distribution of (186)Re in the body was determined by using the values for small colloids as proposed by the International Commission on Radiological Protection (ICRP) Publication 53. The computer code, OLINDA/EXM (Vanderbilt University, Nashville, TN), was used for the calculation of the internal dose. A constant distance of 1 m between the ankle joint and body organs, and of 0.33 m between the elbow or shoulder joint and body organs, was used to calculate the contribution of gamma radiation to the effective radiation dose.The mean effective dose received by hemophiliacs after RSO with (186)Re colloid was 28 +/- 9 microSv/MBq of the activity injected into the joint. The patients received 0.8-3.7 mSv (1.9 +/- 0.8 mSv) owing to the leakage of (186)Re from the treated joint and its retention in the body. The highest doses were established in the spleen (26.0 +/- 10.7 mGy), the liver (17.6 +/- 7.2 mGy), and red marrow (3.0 +/- 0.8 mGy). The contribution of gamma radiation to the effective dose was less than 0.1 mSv in RSO of the ankle, 0.4 mSv in the elbow, and 0.6 mSv in the shoulder-joint treatment. The activity of (186)Re in the regional lymph nodes was noted in 4 of the 14 treatments. In these cases, the estimated average dose received by individual lymph nodes was 14.7 +/- 1.9 Gy.RSO with (186)Re colloid is a safe treatment method. The effective dose received by patients after RSO by using (186)Re colloid is low, as are the radiation doses to the most exposed organs. If (186)Re is retained in the regional lymph nodes, the lymph node radiation dose would be high.

Radiosynoviorthesis is a well-accepted method for the treatment of recurrent hemarthrosis in hemophilic patients.The aims of our study were to evaluate the effectiveness of radiosynoviorthesis in patients suffering from hemophilic hemarthrosis, to determine the effect of treatment on antihemophilic factor consumption, and to assess the patient's satisfaction with radiosynoviorthesis.Between 2001 and 2003, 26 radiosynoviortheses were done in 21 hemophilic patients; in 4 patients the treatment was repeated, and in 1 patient two joints were treated. 90Y colloid was used for the knee joint, and 186Re colloid was used for ankle, shoulder, and elbow radiosynoviorthesis.The bleeding frequency decreased by at least 50% in 53% of patients in the year after radiosynoviorthesis, as compared to the year prior to the therapy. Considering only those patients who had at least 12 bleedings into the treated joints in the year preceding the therapy, the bleeding frequency decreased by at least 50% in 62% of these patients. In this group, the consumption of the antihemophilic factor was notably reduced (on average, by 25,800 I.U./year). All patients reported that the treated joint was much better or better than before the radiosynoviorthesis.Radiosynoviorthesis is an effective method for the treatment of hemophilic hemarthrosis, particularly in patients with frequent intra-articular bleedings. The antihemophilic factor consumption was markedly reduced only in patients with frequent joint bleeding. Radiosynoviorthesis is well accepted by patients suffering from hemophilic hemarthrosis.

A 57-year-old male was admitted with suspected acute coronary syndrome. He reported experiencing moderate chest pain when walking during the day prior to admission, but had very prominent ST segment elevations in the precordial electrocardiography (EKG) leads. A physical examination revealed remarkable severe kyphoscoliosis with chest deformity. The patient’s cardiac troponin levels remained normal, while cardiac ultrasound and magnetic resonance imaging of the chest confirmed hypertrophic cardiomyopathy (HCM) with severe thickening of the interventricular septum. Ischemic heart disease was ruled out by myocardial perfusion imaging with 99mTc-MIBI during rest and dipyridamole-induced stress without showing irreversible or reversible myocardial ischemia. Our diagnosis was that the chest pain was noncardiac in origin and that the pronounced ST segment elevations in the precordial EKG leads reflected the severely hypertrophic interventricular septum through the normally thick left ventricular free wall. The patient’s chest wall deformity brought his septum and the ventricular free wall nearly parallel to the left side of the chest wall, allowing for complete expression of the reciprocal EKG pattern of septal hypertrophy. We suggest that EKG findings should always be interpreted with the chest wall shape being kept in mind.