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Karcinom prostate najčešća je novootkrivena maligna bolest te treći najčešći zloćudni uzrok smrti kod muškaraca u Hrvatskoj. Što točnija dijagnostika inicijalne proširenosti bolesti i rana detekcija lezija u pacijenata s biokemijskim relapsom karcinoma prostate neophodna je za ciljano liječenje i kontrolu bolesti. Konvencionalne slikovne metode u pacijenata s biokemijskim relapsom nemaju dovoljno visoku osjetljivost i specifičnost, osobito pri nižim vrijednostima PSA. Razvoj hibridnih slikovnih metoda poput F-18-kolina i Ga-68-PSMA PET/CT-a omogućio nam je raniju i točniju lokalizaciju metabolički aktivnih presadnica u relapsu bolesti. Prostata specifični membranski antigen (PSMA) je transmembranski protein koji se fiziološki nalazi u benignom tkivu prostate. Tijekom maligne transformacije, PSMA se translocira na luminalnu površinu gdje se prilikom vezanja s radionuklidnim ligandom internalizira u stanicu. Njegova patološka ekspresija nalazi se i u nekim drugim tumorskim tkivima, no najizraženija je u adenokarcinomu prostate. Radi svoje ekspresije PSMA predstavlja idealan marker za obilježavanje radionuklidima u dijagnostičke i terapijske svrhe. Na Kliničkom zavodu za nuklearnu medicinu i zaštitu od zračenja KBC Zagreb od travnja 2021. učinjeno je više od 100 Ga-68-PSMA PET/CT pretraga. Postotak pozitivnih nalaza je 56% (56/100 studija). Lokalni recidiv bolesti nađen je u 16, 07% pozitivnih studija, limfni čvorovi su bili zahvaćeni u 73, 21%, dok su metastaze u kostima nađene u 30, 36% pozitivnih studija. Osnovne promatrane vrijednosti uspoređene s rezultatima studija bile su: PSA, PSAdt (doubling time), GS (Gleason Score) i vrijeme od radikalne prostatektomije. U studijama sa serumskim PSA ≤ 0, 5 ng/ml 50% studija je bilo pozitivno (28/56), dok je u pacijenata s PSA > 0, 5 ng/ml 65, 7% studija bilo pozitivno (28/44). PSAdt imao je visoku korelaciju s pozitivnim nalazom ; u pacijenata s PSAdt ≤ 6 mjeseci 66, 7% studija je bilo pozitivno, dok je u grupi s sporijim PSAdt (> 6 mjeseci ) pozitivan nalaz bio znatno rjeđi – 23, 5%. U pacijenata s GS 7 pozitivan nalaz PSMA PET studija je nađen u 51, 61%, s GS 8 – 53, 33% i u pacijenata s GS 9 u 70% studija. U pacijenata s biokemijskom relapsom unutar godine dana od radikalne prostatektomije 93% studija je bilo pozitivno, dok je u grupi pacijenata s dužim periodom od operacije i biokemijskog relapsa broj pozitivnih nalaza pao ispod 44%. U odnosu na F-18- kolin PET/CT, Ga-68-PSMA PET CT pokazao je sličnu osjetljivost u pacijenata s biokemijskim relapsom i PSA vrijednostima višim od 1 ng/ml. Međutim, u grupi pacijenata s biokemijskom relapsom i PSA vrijednostima ≤ 1 ng/ml, osjetljivost F-18-kolin PET/CT-a je bila niska (prema Treglia G. et al. 27%), dok se Ga-68- PSMA PET/CT u toj populaciji pokazao kao superiornija metoda s i dalje vrlo dobrom osjetljivošću (49, 3%). Ga-68-PSMA PET/CT je pouzdana, visoko specifična i osjetljiva hibridna metoda koja omogućava pacijentima s biokemijskim relapsom bolesti ranu lokalizaciju bolesti, modifikaciju terapije i individualniji pristup terapiji. Posebnu vrijednost PSMA PET/CT imati će u bliskoj budućnosti radi rutinskog probira bolesnika za terapiju s PSMA-terapijskim radiofarmacima (Lu-177 PSMA, Ac-225 PSMA), što će omogućiti još bolje rezultate liječenja.

Cilj: Karcinom prostate najčešća je zloćudna neoplazma u muškaraca te treći uzrok smrtnosti od karcinoma u zemljama Europske unije. Nakon provedene inicijalne terapije, u oko 20-50% pacijenata dolazi do biokemijskog povrata bolesti. Cilj ovog istraživanja bio je ispitati korist nuklearno-medicinske metode F-18-kolin PET/CT-a u procjeni aktivnosti bolesti u bolesnika nakon provedene inicijalne terapije karcinoma prostate, a pod sumnjom na biokemijski povrat bolesti. ----- Metode: U prospektivno istraživanje uključeno je 150 muškaraca nakon provedene inicijalne terapije karcinoma prostate, upućenih od specijalista onkologije ili urologije zbog porasta serumskih vrijednosti ukupnog PSA i sumnje na biokemijski povrat bolesti. Snimljena je pozitronska emisijska tomografija udružena s kompjutoriziranom tomografijom 20 minuta nakon intravenskog injiciranja radiofarmaka F-18-kolin, a injicirane aktivnosti individualizirane su prema tjelesnoj težini svakog ispitanika. Kliničko praćenje od najmanje šest mjeseci uz praćenje vrijednosti ukupnog serumskog PSA i nalaza drugih, konvencionalnih dijagnostičkih metoda (scintigrafije koštanog sustava s Tc-99m-MDP, RTG kostiju, MR zdjelice) smatrano je referentnim standardom. ----- Rezultati: Osjetljivost pretrage F-18-kolin PET/CT-a iznosila je 87,5%, uz specifičnost 36,8%. Preciznost mjerenja iznosila je 74,7%, a omjer izgleda u predikciji uspješnosti terapijskih postupaka 4,04 (95% CI 1,55-1,56), značajno više u odnosu na ostale metode. Nalaz F-18-kolin PET/CT-a ima i značajnu ulogu u predikciji ishoda te promjeni terapijskog pristupa, a ispitanici s pozitivnim nalazom pretrage imali su značajno kraće vrijeme preživljenja. ----- Zaključak: F-18-kolin PET/CT koristan je u procjeni aktivnosti bolesti kod pacijenata s karcinomom prostate i sumnjom na biokemijski povrat bolesti. Osjetljivost i omjer izgleda veći su u odnosu na druge ispitivane metode. Pretraga omogućuje i predikciju ishoda te utječe na promjenu terapijskog pristupa. Pozitivan nalaz pretrage povezan je s predikcijom nepovoljnog ishoda i kraćim vremenom preživljavanja., Aim: The aim of this study was to evaluate the value of F-18-choline PET/CT in prostate cancer patients with biochemical relapse. Methods: In this prospective study, 150 men biochemical relapse of prostate cancer, underwent a whole-body PET/CT 20 minutes after intravenous application of F-18-choline. Clinical follow-up of at least six months was the referent standard with other, conventional diagnostic methods monitoring (Tc-99m-MDP bone scintigraphy, bone X-ray, pelvic MRI) with close follow-up of serum PSA values. Results: F-18-choline PET/CT sensitivity was 87,5%, with 95% CI 79,92% to 92,99%, and specificity was 36,84% (95% CI 21,81% to 54,00%). Diagnostic accuracy was 74,67% (95% CI 66,93% to 81,41%) with odds ratio OR 4,04 (95% CI 1,55 to 10,56), significantly higher than other reported diagnostic methods. F-18-choline PET/CT findings were predictors of unfavourable outcomes, with an impact on treatment change and therapeutic strategies. Conclusion: F-18-choline PET/CT is valuable in biochemical relapse detection in prostate cancer patients. Sensitivity, accuracy and odds ratio of the method are higher than in other reported conventional imaging methods. F-18-choline PET/CT is a predictor of outcomes and influences therapy and treatment changes. Positive findings of F-18-choline PET/CT are correlated with shorter survival times and unfavourable outcomes.

Introduction: Gliomas are associated with varied survival, in part linked with their histological subtype. The diagnosis of low-grade gliomas is challenging, as conventional imaging can often be inconclusive or equivocal. Functional imaging modalities have been introduced to provide additional metabolic information. The objective of this pilot study was to determine primary LGG diagnosis accuracy between F-18 FET and F-18 FCH. Materials and Methods: Eleven patients aged 21 to 80 years ; six of them women, with suspected LGG, diagnosed with 3T magnetic resonance imaging were included in this pilot study from March 2018 to May 2019. Patients underwent both F-18 FET and F- 18 FCH PET/CT scanning within one week, according to standard protocol. Biopsy or surgical tumor ablation with pathohistological diagnosis have been performed in the following month in seven patients. Results: Nine patients had a F-18 FET positive lesion, with SUVmax values ranging from 1, 3 to 3, 1. Six patients positive on F-18 FET PET and negative on F-18 FCH PET had pathohistological diagnosis of low-grade glioma (1 ganglioglioma, 4 diffuse astrocytoma, 1 anaplastic astrocytoma). Two patients with both F-18 FET and F-18 FCH PET avid lesion, had final diagnosis of glioblastoma multiforme. One patient negative on F-18 FET PET and negative on F-18 FCH PET had diagnosis of focal cortical dysplasia. Conclusion: Preliminary results of this pilot study suggest functional imaging provides valuable information, necessary for individual management of patients with LGG. F-18 FET seems to be more accurate than F-18 FCH in primary diagnosis of LGG, while F-18 FCH uptake seems to correlate with higher grade and more aggressive gliomas.

The aim of this prospective pilot study was to evaluate diagnostic accuracy and impact on therapy of F-18-FET and F-18-FCH in patients with brain lesions suggestive of low-grade gliomas (LGG). Materials and Methods: Eleven patients, 21 to 80 years of age, six of them women, have been included in this pilot study. Initial suspected LGG was reported with 3T magnetic resonance brain imaging. All patients underwent both F-18- FET and F-18-FCH PET/CT brain scan within one week. Brain imaging was performed according to standard protocol 20 minutes after intravenous injection 185 MBq of F-18- FET (O-(2-[F-18]-fluoroethyl)-L- tyrosine) and 185 MBq F-18-FCH (fluoromethyl-(F- 18)-dimethyl-2- hydroxyethylammonium chloride). Biopsy or surgical lesion ablation with the pathohistological diagnosis have been performed in the following month in nine patients, and a year- long clinical follow-up was reported in all patients. Results: Nine patients had a F-18-FET positive lesion, with SUVmax values ranging from 1, 3 to 3, 1. Four patients had F-18- FCH uptake in lesions that were also F-18-FET positive, SUVmax ranging from 0, 5 to 3, 9. Two patients were F-18-FET and F- 18-FCH negative, conventional imaging was suggested in followup. Six patients had surgery and maximal tumour reduction. Histologically, grade IV glioblastoma was reported in two patients, who were both F-18-FET and F-18- FCH positive, with higher SUVmax values of metabolically active brain lesions. Diffuse astrocytoma was reported in four patients, anaplastic astrocytoma in one and two patients had gangliogliomas. Lesions histologically reported as lower grade, also had lower values of SUVmax F-18- FET uptake and were either F-18-FCH negative or had only faint F-18-FCH uptake (SUVmax 0, 5 - 0, 8).In a year-long clinical follow-up period, one patient, negative on both F- 18-FET and F-18-FCH, has no morphological evidence of disease progression, any new therapy, or clinical signs of any brain disorder. One of the patients with aggressive grade IV glioblastoma and the highest SUVmax values of both F-18-FET and F-18-FCH has clinical and morphological progression of the disease. Chemoradiotherapy was included after surgery in five patients, with astrocytoma and glioblastoma histological diagnosis. Conclusion: Preliminary results of this pilot study on a small patient sample suggest functional imaging provides valuable additional information, necessary for individual patient management and further treatment. Amino acid and protein synthesis imaging gives important data on lesion volume and spread, while increased lipid synthesis seems to correlate with higher grade and more aggressive gliomas.

Introduction: The aim of this study was to evaluate the value of F-18 choline PET/CT in initial staging of high-risk prostate cancer patients. Subjects and methods: Hundred consecutive biopsy confirmed prostate cancer patients were scanned with F-18-choline PET/CT from February 2012 to April 2018. Mean PSA value at referral was 48, 4 ng/ml (range 4, 3 to 280, 6). Functional imaging was proposed in high risk patients and after equivocal conventional imaging and bone scintigraphy findings. Imaging was performed after administration of F-18 choline (2- 3 MBq/kg, mean 209 MBq). All patients had a minimum 6-month follow-up. Results: There were 24 patients without metastases, while the majority of patients (76%) had a choline scan positive for metastatic disease. Eight patients had a single positive pelvic lymph node, with a short axis diameter shorter than 1 cm. 56 patients had FCH positive metastastic disease in lymph nodes only (mean SUV 6, 4), 25 in lymph nodes and/or skeleton (mean SUV 10, 7). In sixteen patients seminal vesicles’ infiltration was found. Majority of our patient population had a combination of radiotherapy and hormonal therapy, with the mean PSA levels after six months significantly lower (2, 1 ng/ml). Conclusion: F-18-choline PET/CT provides clinicians with valuable information in staging of high-risk prostate cancer. It has an important impact on therapeutic strategy, providing additional data necessary for the appropriate and individual patient management.

Cilj: Karcinom prostate najčešća je zloćudna neoplazma u muškaraca te treći uzrok smrtnosti od karcinoma u zemljama Europske unije. Nakon provedene inicijalne terapije, u oko 20-50% pacijenata dolazi do biokemijskog povrata bolesti. Cilj ovog istraživanja bio je ispitati korist nuklearno-medicinske metode F-18-kolin PET/CT-a u procjeni aktivnosti bolesti u bolesnika nakon provedene inicijalne terapije karcinoma prostate, a pod sumnjom na biokemijski povrat bolesti. Metode: U prospektivno istraživanje uključeno je 150 muškaraca nakon provedene inicijalne terapije karcinoma prostate, upućenih od specijalista onkologije ili urologije zbog porasta serumskih vrijednosti ukupnog PSA i sumnje na biokemijski povrat bolesti. Snimljena je pozitronska emisijska tomografija udružena s kompjutoriziranom tomografijom 20 minuta nakon intravenskog injiciranja radiofarmaka F-18-kolin, a injicirane aktivnosti individualizirane su prema tjelesnoj težini svakog ispitanika. Kliničko praćenje od najmanje šest mjeseci uz praćenje vrijednosti ukupnog serumskog PSA i nalaza drugih, konvencionalnih dijagnostičkih metoda (scintigrafije koštanog sustava s Tc-99m-MDP, RTG kostiju, MR zdjelice) smatrano je referentnim standardom. Rezultati: Osjetljivost pretrage F- 18-kolin PET/CT-a iznosila je 87, 5%, uz specifičnost 36, 8%. Preciznost mjerenja iznosila je 74, 7%, a omjer izgleda u predikciji uspješnosti terapijskih postupaka 4, 04 (95% CI 1, 55-10, 56), značajno više u odnosu na ostale metode. Nalaz F- 18-kolin PET/CT-a ima i značajnu ulogu u predikciji ishoda te promjeni terapijskog pristupa, a ispitanici s pozitivnim nalazom pretrage imali su značajno kraće vrijeme preživljenja. Zaključak: F-18-kolin PET/CT koristan je u procjeni aktivnosti bolesti kod pacijenata s karcinomom prostate i sumnjom na biokemijski povrat bolesti. Osjetljivost i omjer izgleda veći su u odnosu na druge ispitivane metode. Pretraga omogućuje i predikciju ishoda te utječe na promjenu terapijskog pristupa. Pozitivan nalaz pretrage povezan je s predikcijom nepovoljnog ishoda i kraćim vremenom preživljavanja.

Epilepsy is one of the most common neurological disorders and despite modern medical therapy, seizures are not adequately controlled in 25% of patients and they suffer severe morbidity, disability and social isolation. Over years, surgical treatment of epilepsy has become more sophisticated and accessible in the majority of modern countries. The objective of this review is to report on a series of patients with intractable epilepsy who underwent invasive monitoring and surgery or surgery alone when presurgical noninvasive workout showed clear surgical focus. The main challenge is whether to do a set of presurgical workout or rely on semiology and basic diagnostic procedures (electroencephalogram and 3T magnetic resonance imaging, MRI). Complex MRI positive epilepsy requires further method such as positron emission tomography (PET) and single photon emission computed tomography (SPECT) procedures, and even invasive monitoring. Through several case reports, we will discuss the decision-making process for certain patients. Presurgical workup determines the epileptic zone, the removal of which can lead to seizure freedom with an additional goal to spare the regions that mediate the key neurological functions. Modern imaging and electrophysiological methods reveal more subtle changes within the brain, and without 3T MRI with postprocessing software, PET, SPECT and invasive monitoring, tailored epilepsy surgery will never develop further. Our comprehensive team consists of dedicated neurologists, neuropsychologists, neuroradiologists and neurosurgeons. Hippocampal sclerosis is the most common cause of complex partial epilepsy of the temporal origin. Surgical resection is often the only way to gain seizure freedom in patients due to very common pharmacoresistance associated with that kind of pathology. In our series of over 100 selective amygdalohippocampectomies, seizure freedom was achieved in 85% of cases. Malformations of cortical development are a heterogeneous group of disorders characterized by abnormal cerebral cortical cytoarchitecture. Surgical excision or disconnection are the procedures which commonly end up with seizure freedom if they are not within the functional cortex. Callosotomy is very efficient in patients with drop attack, and we found it very useful when vagus nerve stimulation fails in epilepsy control. In conclusion, current types of surgical resections after invasive monitoring and extensive presurgical workout produce excellent treatment results with a high rate of seizure freedom in up to 60%-80% of cases, and a very low rate of permanent morbidity. In our series of patients, mortality rate was 0% and morbidity rate 4%.

Defining epileptogenic networks is essential in the presurgical treatment of patients with pharmacoresistant epilepsy. Epileptogenic networks are defined by the brain region involved in the production and propagation of epileptic activities. The concept of epileptogenic networks is widely accepted as a more effective model of explaining the complex dynamics between epileptic seizures and epileptic anomalies within the brain. This dynamics is also a reason for discrepancies between semiology and pharmacoresistance of epilepsy, as well as epilepsy surgery failure. The process of emergence of epileptogenic networks is complex and determined by various factors. Still, a certain pattern does exist as a result of functional and anatomical connections within the brain. If semiology of seizures is clearly identifiable and well-known, it can provide useful data on epilepsy onset and spread. This is supposed to be a starting point for further treatment. After semiology has been defined, further methods for defining networks are needed. Apart from video electroencephalography (EEG) and brain magnetic resonance imaging (MRI), further diagnostics would include neuropsychological testing, brain positron emission tomography (PET) and single-photon emission computed tomography (SPECT), functional MRI, magnetoencephalography (MEG), as well as post-processing of brain MRI images with the Morphometric Analysis Program. Final confirmation of existence of epileptogenic networks is only possible by use of invasive EEG monitoring. After data have been collected by use of all of these methods, it is possible to partially define epileptogenic networks and explore options for further treatment, which is most likely to be a surgical one. Yet, expectations of the outcome may be only partially fulfilled, as epileptogenic networks are complex and very often overlapping with eloquent cortex and prone to changes during long-standing course of epilepsy.

Gliomas are associated with varied surivival, in part linked with their histological subtype. Funcional imaging modalities can provide addiotional metabolic information. F-18- fluoroethyl -thyrosine displays a high tumour to bacground ration and o accumulation in inflammatory lesion. F-18-choline displays low uptake in normal brain parenchyma. Methods: 11 patients aged 21-80 years were involved. They underwent F-18-FCH and F-18-FET PET/CT within one week. Results: Eleven patients with suspected LGG underwent MRI and PET/CT scans. 9/11 underwent surger and histological diagnosis. 6 were positive on F-18-FET (SUVmax ranging from 1, 3-3, 1), with a histological diagnosis of LGG. Two patients had both FET and FCH positive lesions, histologically glioblasoma multiforme. One patient was double tracer negative, histologically cortical dysplasia. Conclusion: F-18 FET seems to be more accurate than F-18-FCH in primary diagnostis of LGG. Appropirate radiopharmaceutical should be chosen before performing PET/CT.

Epilepsy is a common neurological disease affecting 1% of the population, which in many instances turns out to be a life-long chronic burden with consequences that can sometimes be quite severe, e.g., excessive bodily injury, neuropsychological and psychiatric impairment, social disability, higher mortality rates, and overall reduced quality of life. The gold standard of epilepsy treatment is permanent therapy with antiepileptic drugs (AEDs) based on the concept of prophylactic suppression of seizure activity. Around one-third of patients have pharmacoresistant epilepsy and interestingly, the proportion of these patients has not considerably changed with the introduction of newer AEDs since the early 1990s. According to the definition of the International League Against Epilepsy, AED resistance is defined as “failure of adequate trials of two tolerated, appropriately chosen and used AED schedules (whether as monotherapies or in combination) to achieve seizure freedom”. Current treatment options for these patients include surgical removal of the seizure focus, and alternative approaches such as neurostimulation (vagus nerve stimulation, responsive neurostimulation, deep brain stimulation), ketogenic diet, as well as lifestyle changes. In these patients, nonpharmacological treatment options should be considered early rather than late, but only resective epilepsy surgery can be curative. Epilepsy surgery is an evidence-based treatment option for patients with pharmacoresistant focal epilepsy, with the rate of seizure-free surgical outcomes ranging from 70% to 80% in well-selected cases. Several randomized controlled trials have demonstrated that surgical treatment is safe and effective for pharmacoresistant epilepsy, yet this therapy is still underutilized. There are examples of epileptic syndromes and diagnoses for which epilepsy surgery may be suggested only by noninvasive presurgical diagnostics (mesial temporal lobe epilepsy associated with hippocampal sclerosis, circumscribed epileptogenic lesions (not near eloquent areas), benign neoplasms, vascular malformations, epileptic encephalopathies and multifocal disease (for corpus callosotomy), etc.). In other cases, surgery may be suggested only after additional invasive presurgical diagnostics (temporal lobe epilepsy with discordant electroclinical data, normal magnetic resonance imaging, extratemporal circumscribed epileptogenic lesions close to eloquent area, malformations of cortical development, and dual pathologies). Data from epilepsy surgery studies show that people with shorter epilepsy duration are more likely to be seizure-free at follow-up. In addition, longer epilepsy duration is the only modifiable predictor of impaired adaptive and cognitive development, thus supporting early surgical intervention. Therefore, patients who might benefit from epilepsy surgery should be referred for presurgical assessment without delay. Early surgical intervention for appropriately chosen patients with pharmacoresistant epilepsy offers the best opportunity to avoid lifetime disability and premature death.

The aim of this study is to evaluate the role and value of F-18 choline PET/CT in initial staging and primary evaluation of prostate cancer extent. Materials and Methods: Hundred consecutive patients were scanned with F- 18-choline PET/CT in from February 2012 to April 2018. Mean age of our patient population was 68 years (range 52 to 85 years). Mean PSA value at referral was 48, 4 ng/ml (range 4, 3 to 280, 6 ng/ml). Patients had prostate biopsy performed prior to the scan, and were diagnosed with prostate adenocarcinoma, 41 in the highrisk group. Functional imaging was proposed after equivocal or negative conventional imaging findings (abdominal and pelvic MSCT), and equivocal findings of Tc-99m MDP bone scintigraphy. Results of Tc-99m MDP bone scintigraphy were available in 82 patients, most of them positive or equivocal for metastases, 89%. Mean administered activity was 209 MBq of F-18 choline (2-3 MBq/kg, IASOCholine, IASON GmBH). After the F-18 FCH scan patients had a minimum 6- month follow-up, ranging from 6 to 60 months. Results: Twenty four patients had localized prostate cancer with no positive metastases, while the majority of patients, 76%, had an F-18 FCH PET/CT scan positive for metastatic disease. Eight patients had a single positive pelvic lymph node, with a short axis diameter smaller than 1 cm. The other 68 patients had FCH positive metastatic disease, in seminal vesicles, lymph nodes and/or bone metastases. Fifty-six patients had lymph node metastases, with the mean SUVmax value was 6, 4, ranging from 2 to 22. Twenty-five patients had bone metastases, with the mean value of SUVmax 10, 7 ; ranging from 3, 8 to 23, 3. Sixteen patients had pathological uptake in the seminal vesicles. In the follow-up period change of management was observed in about two-thirds of patients, with a surgical approach chosen in ten patients with no FCH positive metastases. The majority of our patient population had a combination of radiotherapy and hormonal therapy, 60 %. Bilateral orchidectomy was performed in 12 patients, and 6 of them had an added docetaxel chemotherapy. Mean PSA levels after six months of therapy and follow up was significantly lower than the baseline value, 2, 1 ng/ml, ranging from undetectably low to the maximum value of 79 ng/ml. Conclusion: F- 18- choline PET/CT provides clinicians with valuable information in the staging of prostate cancer. It has an important impact on therapeutic strategy, providing additional data necessary for the appropriate and individual patient management.

The aim of study was to determine the risk of calcium oxatae urolithiasis in children from concentrations of calcum, oxalate, citrate, glycosaminoglycans in urine and their ratios, all standardized in respect to creatinine. Calcium/citrate ratio as well as oxalate/(citratexglycosaminoglycans) ratio proved to be usefull for diagnostic purposes in calcium oxaqlate stone fromers.

Urinary excretion of oxalate, citrate, glycosaminoglycans and the ratios oxalate/citrate, oxalate/glycosaminoglycans, oxalate/(citrate × glycosaminoglycans), and citrate/glycosaminoglycans were examined in 83 children with idiopathic urolithiasis. Only the variable oxalate/(citrate × glycosaminoglycans) mmol/mol creatinine was able to distinguish between children with urolithiasis and healthy children. ROC analysis showed with high specificity that the value of the ratio > 0.0782 is adequate for diagnostic purpose showing.

Analizirano je izlučivanje urinom oksalata, citrata i glikozaminoglikana u 83 djece s idiopatskom urolitijazom. Iz analize su isključene primarne hiperoksalurije i idiopatske hiperokslurije (HOGA 1) koje su uzrokovane mutacijama gena i enteričkom hiperoksalurijom. Kao varijable su uzete koncentracije oksalata, citrata i glikozaminoglikana te omjeri oksalati/citrati, oksalati/glikozaminglikani, oksalati/(citrati × glikozaminoglikani) i citrati/glikozaminoglikani. Od ispitanih varijabli jedino je omjer oksalati/(citrati × glikozaminoglikani) mmol/mol kreatinina razlikovao zdravu djecu od skupine djece s uirolitijazom. ROC analizom je utvrđeno da je vrijednost omjera > 0.0782 dijagnostički prihvatljiva za razlikovanje djece s urolitijazom od zdrave djece. Stoga se nalaz omjera oksalati/(citrati × glikozaminoglikani) iznad 0.0782 može se smatrati određujućim za djecu s urolitijazom.

Nedavne epidemiološke studije bilježe porast učestalosti urolitijaze u djece u svijetu. Ispitali smo demografske i kliničke karakteristike naše djece s urolitijazom i također odredili metaboličke činitelje rizika nastanka urolitijaze. Retrospektivno su anlizirani podatci 76-ero djece s urolitijazom iz različitih dijelova Hrvatske koje smo pratili od 2002-2011 godine. Učestalost urolitijaze procijenili smo na 65/100.000 djece mlađe od 18 godina. U posljednjih 10 godina zabilježen je dvostruki porast učestalosti sa 0.6 (2002) na 1.1 (2011). U 75% djece riječ je bila o kalcij oksalatnom kamencu. Najčešći metabolički rizični faktor bila je hiperkalciurija a potom idiopatska ili umjerena hiperoksalurija. Saturacija urina (EQUIL2) bila je povišena u 62% djece. Studija je dala uvid u učestalost urolitijaze u djece u našoj zemlji i identificirala činitelje rizika. Obilježja urolitijaze u naše djece slična su onim razvijenih zemalja.

The Eighth International Congress of the Croatian Society of Nuclear Medicine was held in Šibenik, May 09-12, 2014. It gave an overview of the status of nuclear medicine in the region. Eighty-five papers were selected. The program included 22 invited lectures, 32 oral presentations and 31 poster presentations. Presenters came from 14 European countries (Austria, Croatia, Italy, Slovenia, Hungary, Bosnia and Herzegovina, Germany, Serbia, Montenegro, Bulgaria, UK, Russia, Netherlands, France), and from USA and India. This report includes top 24 papers as ranged by the international Scientific Committee, which might be interesting to the readers of Nuklearmedizin journal.

AIM: The purpose of this study is to determine the accuracy and clinical usefulness of ultrasound guided core biopsy for diagnosing suspicious radiologically detected breast lesions. ----- PATIENTS AND METHODS: We retrospectively evaluated the results of percutaneous core biopsy with 14-gauge needles performed over a period of 14 months on 229 suspicious lesions detectable on mammography and/or ultrasound exam (BI-RADS 4 or 5). The imaging-histological concordance was ascertained for each lesion. In cases of discordance, repeat biopsy or surgical excision was performed. Six-month ultrasound control was recommended in cases of benign lesions. For borderline and malignant lesions a surgical excision was done. Concordance between biopsy results and subsequent examinations (surgical excision or follow-up) was also evaluated. ----- RESULTS: Histological analysis of core biopsy samples showed 143 (62.4%) benign lesions, 21 (9.2%) borderline lesions and 65 (28.4%) malignant lesions. Follow-up, repeated biopsy, or surgical excision showed four false negative cases. Accuracy of ultrasound guided core biopsy was 98.3%. ----- CONCLUSION: Ultrasound guided core biopsy is a safe and reliable method for diagnosing suspicious breast lesions without any significant complications as was reported in previous studies.

Aim/Introduction: Gliomas, as one of the more commonly diagnosed primary brain tumours, are associated with variable survival, in part linked with their histological type. The diagnosis of low grade gliomas (LGG) is challenging, as results of radiological imaging modalities can often be inconclusive or equivocal. Functional imaging modalities have been introduced to provide additional metabolic information. O- (2-[18F]- fluoroethyl) -L-tyrosine (18F-FET) is PET radiopharmaceutical approved for the characterisation of glioma-suggestive brain lesions. 18F-FET displays a high tumour-to- background ratio and minimal accumulation in inflammatory lesions. Because of low uptake in healthy brain parenchyma, fluoromethyl-(18F)- dimethyl-2- hydroxyethylammonium chloride (18F- FCH) has also been used for diagnosis of LGG is some european nuclear medicine units. The objective of this pilot study was to investigate the diagnostic accuracy of 18F-FET and 18F-FCH PET in patients with primary LGG. Materials and Methods: Eleven patients aged 21-80 years with MRI-suspected LGG were involved in this study. Patients underwent both 18F-FET and 18F-FCH PET/ CT within one week. Brain PET/CT was performed according to standard protocol: 20 minutes after intravenous injection of 185 MBq of 18F-FET and 185 MBq of 18F-FCH PET. Surgery and histological diagnoses were performed in the next two weeks. Results: Eleven out of 11 patients with suspected LGG underwent MRI, 18F-FET and 18F-FCH PET/CT. All patients had LGG according to MRI. In all PET positive patients, tumour location on MRI was consistent with region of PET/ CT positivity. Nine out of 11 patients with suspected LGG had final histological diagnosis after the surgery. Two out of 11 patients included in this study did not undergo surgery or biopsy for histological confirmation. Both had negative 18F-FET and negative 18F-FCH PET scan, so they declined surgery and multidisciplinary tumour board recommended follow-up. Seven lesions positive on 18F-FET PET and negative on 18F-FCH PET scan were diffuse astrocytoma (grade II), ganglioma (grade I) and anaplastic astrocytoma (grade III) by pathohistology. Two lesions positive on 18F-FET PET and positive on 18F-FCH PET scan were glioblastoma multiforme (grade IV) by pathohistology. Conclusion: Preliminary results on a small patient sample suggest appropriate radiopharmaceutical should be chosen before performing PET/CT scan in patients with newly diagnosed LGG. 18F-FET is more accurate radiopharmaceutical than 18F-FCH in detection of LGG, while increased lipid synthesis seems to correlate with higher grade and more aggressive gliomas.