Multimodal radionuclide shuntography for device patency: New procedural tips for anuncommon historical technique.

Cerebrospinal fluid (CSF) shunting is an established long-term treatment option for hydrocephalus, and is one of the most commonly performed neurosurgical procedures in western countries.Despite advances in CSF shunt design and management, its failure rates remain high and is most commonly due to obstruction and infection.Cerebrospinal fluidshunt failure diagnosis should be prompt and accurate in establishing timely if its revision is appropriate. Radionuclide shuntography with technetium-99m-diethylenetriaminepetaacetic acid (99mTc-DTPA) is a useful technique for evaluation CSF shunts and management of patients presenting with shunt-related problems, in particular it can avoid unnecessary replacement interventions. Although its execution and interpretation require specific skills, we suggest its execution for the evaluation of device's patency. We here describe the radionuclide shuntography performed with recent hybrid multimodal technologies, with a procedure customized to a complicated patient with hydrocefalus and neoplastic disease. We suggest considering radionuclide shuntography in association with conventional imaging and strongly recommend the additional performance of single photon emission computed tomography/computed tomography (SPECT/CT) because it also provides valuable information to complete the interpretation of planar images.

Safety culture to improve accidental event reporting in radiotherapy.

BACKGROUND AND PURPOSE: The potential for unintended and adverse radiation exposure in radiotherapy (RT) is real and should be studied because RT is a highly complex, multistep process, which requires input from numerous individuals from different areas and steps of the RT workflow. The 'Incident' (I) is an event the consequence of which is not negligible from the point of view of protection or safety. A 'near miss' (NM) is defined as an event that is highly likely to happen but did not occur. The purpose of this work is to show that through systematic reporting and analysis of these adverse events, their occurrence can be reduced. MATERIALS AND METHODS: Staff were trained to report every type of unintended and adverse radiation exposure and to provide a full description of it. RESULTS: By 2018, 110 worksheets had been collected, with an average of 6.1 adverse events per year (with 780 patients treated per year, meaning an average incident rate of 0.78%). In 2001-2009, 37 events were registered (13 I and 24 NM), the majority of them were in the decision phase (12/37), while in 2010-2013, there were 42 (1 I and 41 NM) in both the dose-calculation and transfer phase (19/42). In 2014-2018, 31 events (1 I and 30 NM) were equally distributed across the phases of the RT process. In 9/15 cases of I, some checkpoint was introduced. CONCLUSION: The complexity of the RT workflow is prone to errors, and this must be taken into account by encouraging a safety culture. The aim of this paper is to present the collected incidents and near misses and to show how organization and practice were modified by the acquired knowledge.

18F-FDG PET/CT in GIST treatment response evaluation beyond Imatinib.

Positron emission tomography/computed tomography (PET/CT) represents a reliable promising tool in treatment response evaluation of new therapies beyond Imatinib in gastrointestinal stromal tumors (GIST). This narrative review aims to discuss the literature about the role of fluorine-18-fluorodeoxyglucose (18F-FDG) PET/CT in evaluating response in new tyrosine kinase inhibitors (TKI) and radiotherapy (RT) in GIST patients. A comprehensive literature search was performed to retrieve original studies published on PubMed, Scopus and Google Scholar databases. Eighteen studies including 382 patients with GIST were selected. Main findings of included studies are presented. Fluorine-18-FDG PET/CT may enhance performance in GIST management providing significant information in evaluation of treatment response and representing a strong predictor of clinical outcome.

Typical and atypical PET/CT findings in non-cancerous conditions.

Nuclear Medicine multimodality imaging, such as positron emission tomography/computed tomography PET/CT, refers to metabolic tissue characteristics integrated with anatomical details. Fluorine-18-fluorodeoxyglucose (18F-FDG) is the most diffuse radiopharmaceutical and its application is spreading beyond the area of oncology. The causes of high 18F-FDG uptake that were once considered false positives have been identified and the new knowledge about them led to non-cancerous pathologies that can be studied by 18F-FDG PET/CT. This technique, due to the inflammatory cells high avidity of 18F-FDG, can be useful in studying a variety of inflammatory and infectious systemic conditions. Studies performed in patients with fever of unknown origin (FUO) indicate that 18F-FDG PET/CT offer a great advantage of detecting malignancy, inflammation and infection at the same time both in adults and children. Furthermore, the 18F-FDG PET/CT has proved useful in the study of specific organs such as the heart and brain that represent separate topics also for the development of new specific radiopharmaceuticals. In all the non-oncologic conditions 18F-FDG PET/CT imaging may offer an "all-in-one" procedure, thanks also to its panoramic whole-body acquisition, as an alternative to other diagnostic procedures, reducing the number of unnecessary investigations. The 18F-FDG PET/CT finding of the simultaneous presence of radiopharmaceutical uptake for multiple disease interconnect to different medical disciplines. It is important to describe unexpected occasional typical or atypical PET/CT findings to the growth of scientific and medical community; it can be the starting point to the enlargement of PET/CT indications for a better and wider comprehension of the human system. To recognize unexpected occasional findings is very important a well knowledge of many aspects: physiological biodistribution, diagnostic imaging instrumentations and techniques, pathological aspects of the different neoplastic diseases, patient story, such as previous therapy, and its comorbidity. An unexpected occasional finding can lead to suggest further tests or investigations in order to have a wider comprehension of patients' clinical situation and they are easily explainable when we have a physician's approach towards patient.

How often suspected pulmonary embolism is diagnosed and its main diagnostic characteristics, in an emergency nuclear medicine service? Four years experience.

OBJECTIVE: Acute pulmonary embolism (APE) is an emergency condition and its treatment must be immediate. Nevertheless, the diagnosis of APE is diffcult because its symptoms and risk factors are not specific. We present our 4 years experience on this subject. SUBJECTS AND METHODS: We retrospectively studied 2178 lung perfusion scintigraphies (LPS). Of them 1846 were performed to patients suspected for APE admitted to the emergency departments of the University Polyclinic of Bari and examined immediately by our Nuclear Medicine Department. Contingency tables and odds ratio (OR) were used to estimate the relation between symptoms, risk factors, D-dimers dosage, other imaging diagnostic tools and LPS results. RESULTS: Lung perfusion scintigraphy was positive for APE in 309/1846 (16.7%) patients which then were treated successfully. In 89.5% of these, 309 patients D-dimer dosage was previously examined and was increased in 97.7% of them, but was not predictive of APE (OR=1.04, P=1). Among all symptoms, a low diagnostic capacity was found for cough (OR=1.25, P=0.066) and for chest pain (OR=0.95, P=649). On the contrary, dyspnea was a significant symptom correlated with positive LPS (OR=1.78, P<0.001). The presence of risk factors was predictive of positive LPS and positively correlated with the number of positive 2 oglin lesions in LPS. x2loglin=6.472, P=0.011). Lung perfusion scintigraphy positive for APE were significantly associated with computed tomography pulmonary angiography and/or chest X-ray results (x =9.618, P=0.022). CONCLUSION: Lung perfusion scintigraphy could early diagnose APE in 16.7% of the cases (referred to our Nuclear Medicine Emergency Service) and exclude APE in 83.3% of these cases. Immediate treatment or release of these patients from the emergency department was thus possible. LPS has a key role in the early diagnosis but even more in exclusion of APE, optimizing the management of patients who do not require admission to intensive care. Our four-year and large-scale experience, based on clinical and resource optimization, support the need of Nuclear Medicine Units to perform LPS as emergency in on-call 24 hrs service.

Sickle cell diseases: What can nuclear medicine offer?

Sickle cell disease (SCD) is the best known haemoglobinopathy, caused by a mutation substituting valina for glutamic acid at position 6 of the beta-globin chain of adult hemoglobin A, resulting in hemoglobin S (HbS). The homozygous HbS disease (HbSS), an autosomal recessive disorder, is the most common form and the Mediterranean area, along with sub-Saharian African and India, have the highest prevalence (1%-15%). In particular, Sicily with a prevalence of 2%-5%, is among the most interested regions. However, migratory flows have led to a wider diffusion of the disease no longer confined to endemic areas. In Europe, the yearly estimate of affected births are 1,300 but more than 90% of children with SCD survive into adulthood thanks to screening programs and early available care; however, their lifespan remains shortened by two or three decades compared to general population. In Greece, the number of affected births surpassing 100,000 yearly and the total number of newborns carrying two deleterious genes, if no prevention measures are taken, is estimated to be about 120-130/year. Diagnosis of SCD is based on analysis of haemoglobin through protein electrophoresis or chromatography, that are cheap and widely available techniques, even if haemoglobin mass spectrometry and DNA analysis are techniques with high-throughput testing. Prenatal diagnosis is used in many European countries, so the number of affected newborns has significantly decreased during the last 3 years. Over the course of SCD, sickling process may cause acute and chronic abdominal pain due to vaso-occlusive crisis, bone pain often in long bones due to bone marrow infarction, chronic hemolytic anemia, splenic sequestration with rapid enlargement of the spleen, delayed sexual maturation and cholelithiasis, with important inter-indivuidual variability. Sickle hepatopathy reflects liver sickling process within hepatic sinusoids and includes gallstone disease, hepatic sequestration, hepatic sideroris, acute sickle cell hepatic crises (ASHC) and sickle cell intrahepatic cholestasis (SCIC). Clinically, it appears with fever, right upper quadrant pain, jaundice and increased serum liver function tests. These patients are repeatedly esposed to trasfused red cells that contributes to iron overload and may contribute to hepatic haemosiderosis. Increased bone turnover and resorption by osteoclasts and by marrow expansion due to activation of hematopoiesis. The hematopoietic system may expand physiologically. Computed tomography (CT) is an easily reproducible imaging method that allows the morphologic whole-body evaluation although with a high dose of radiation exposure and possible side effects from intravenous contrast media. Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive technique without radiation chosen to image cholangiopathy and may be followed by the execution of endoscopic retrograde cholangiopancreatography (ERCP) in case of gallstone disease. Otherwise it can be helpful in identifying extramedullary hematopoiesis sites. Dual-energy X-rays absorptiometry (DEXA) is performed to evaluate deficit of bone mineral density (BMD), in which reduction of osteoblastic activity, high risk for necrosis may induce to fragility fractures. We recently had the experience of a typical case of a 56 years old Albanian woman with SCD, with jaundice after a long history of recurrent vaso-occlusive crisis. She was submitted to splenectomy and cholecystectomy 5 years before and since then she was treated with hydroxyurea. Hemocromatosis was excluded by genetic analysis. Hepatic biopsy (Pearl's stain) showed sinusoidal dilatation and diffuse iron accumulation in hepatocytes and Kupffer cells. Endo-hepatic jaundice was observed in MRCP images. It was interesting that DEXA examination was within normal range in both right proximal femur. This may probably be due to the presence of sclerotic lesions in the vertebrae, as was seen in the CT images. Technetium-99m-methylen bisphosphonate (99mTc-MDP) skeletal scintigraphy is a higly sensitive whole-body diagnostic nuclear medicine technique able to evaluate early bone metabolic changes. Multimodality SPET/CT allows to correlate scintigraphic findings with anatomical images with higher sensitivity and specificity. The higher uptake of 99mTc-MDP in SCD patients is due to the activation of hematopoetic system and relies on the osteoblastic response to bone resorption as in our patient. The 99mTc-MDP scan may be better than fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) to show sclerotic lesions. Technetium-99m nanocolloids bone marrow scintigraphy (BMS) provides information about the assessment of the reticulum-endothelial system (RES), the whole-body distribution of functional red bone marrow and the presence and the extent of extramedullary hematopoiesis, especially in liver, spleen and bone marrow. Fluorine-18-FDG PET/CT completes the whole-body assessment with an integrated multimodal approach with high spatial resolution that evaluates the metabolic activity and the standardized uptake value (SUV) in SCD patients. Modern genetic diagnosis and gene treatment give promise for having fewer cases of SCD in the future.

18F-FDG PET/CT in therapy response and in predicting responders or non-responders in malignant pleural mesothelioma patients, by using semi-quantitative mRECIST and EORTC criteria.

OBJECTIVE: To evaluate the role of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in therapy response assessment according modified response evaluating criteria of solid tumors (mRECIST) and the predictive role of volume-based semi-quantitative parameters in patients with malignant pleural mesothelioma (MPM). Furthermore modified RECIST criteria for MPM mRECIST and the European Organization for Research and Treatment of Cancer (EORTC) criteria were compared and the predictive role of 18F-FDG PET/CT in the post-therapy outcome. SUBJECTS AND METHODS: Thirty five selected patients with MPM underwent 18F-FDG PET/CT scan at baseline (1) and after therapy (2). Semi-quantitative 18F-FDG PET/CT parameters were collected for each scan and also differences (Δ) ΔSUVmax, ΔSUVav, ΔMTV, ΔTLG, response index (RI)max% and RIav% were evaluated. Radiologic response to therapy was assessed by using the mRECIST and EORTC. RESULTS: The correlation between response to therapy assessed by EORTC and mRECIST criteria was moderate (K=0.418; 95%CI:0099-0736). According to mRECIST, statistical differences between responders and non-responders were significant in the analysis of semi-quantitative parameters. According mRECIST criteria, all parameters defined a good area under the curve (AUC) but the better AUC resulted for ΔMTV (cut-off≤11.3, sensitivity=91.3%, specificity=91.7%) and ΔTLG (cut-off≤59.1, sensitivity=82.6%, specificity=100%). Kaplan-Meier curves between responders and non-responders did not show statistically significant differences. CONCLUSION: The semi-quantitative analysis of 18F-FDG PET/CT has an important role in MPM therapy response assessment and has a predictive role in distinguishing responders and non-responders.

Multimodality Imaging in Tumor Angiogenesis: Present Status and Perspectives.

Angiogenesis is a complex biological process that plays a central role in progression of tumor growth and metastasis. It led to a search for antiangiogenic molecules, and to design antiangiogenic strategies for cancer treatment. Noninvasive molecular imaging, such as positron emission tomography (PET) and single photon emission computed tomography (SPECT), could be useful for lesion detection, to select patients likely to respond to antiangiogenic therapies, to confirm successful targeting, and dose optimization. Additionally, nuclear imaging techniques could also aid in the development of new angiogenesis-targeted drugs and their validation. Angiogenesis imaging can be categorized as targeted at three major cell types: (I) non-endothelial cell targets, (II) endothelial cell targets, and (III) extracellular matrix proteins and matrix proteases. Even if radiopharmaceuticals studying the metabolism and hypoxia can be also used for the study of angiogenesis, many of the agents used in nuclear imaging for this purpose are yet to be investigated. The purpose of this review is to describe the role of molecular imaging in tumor angiogenesis, highlighting the advances in this field.

Increased and normalized uptake of 18F-FDG in a case of bone periprosthetic infection treated by antibiotics.

We report the case of a 69 years old man with left hip prosthesis, who presented clinical, biochemical and imaging signs of periprosthetic infection treated with linezolid, an antibacterial agent of the oxazolidinone class. Two weeks after this treatment, a fluorine-18-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) scan showed increased uptake in the skeleton and also increased uptake in several focal areas in the spine and near the prosthesis and the surgical wound on the left gluteus medius. Bone marrow biopsy was negative; meanwhile the antibiotic therapy, after four weeks of treatment was stopped due to red blood cells and platelets toxicity. Six weeks later, the patient developed high fever again and in order to revaluate the periprosthetic inflammation, he was resubmitted to 18F-FDG PET/CT which showed normal 18F-FDG uptake in the whole skeleton, including the prosthesis and the subcutaneous wound. Some focal areas of increased uptake in the lumbar spine were still detected. In the next 4 weeks the patient was under a "watch and wait" follow-up in a steady state. IN CONCLUSION: In the case we report, since we found no otnt focal areas in the lumbar spine where due to age-related bone deformities including some Schmorl's nodes. The inflammation in the bone prosthesis and the subcutaneous wound responded almost totally to the antibiotic treatment we applied.

Comparison of (18)F-FDG PET/CT methods of analysis for predicting response to neoadjuvant chemoradiation therapy in patients with locally advanced low rectal cancer.

PURPOSE: The aim of this study was to prospectively investigate the predictive value of (18)F-FDG PET/CT semiquantitative parameters for locally advanced low rectal cancer (LARC) treated by neoadjuvant chemoradiation therapy (nCRT). METHODS: 68 patients with LARC had (18)F-FDG PET/CT scans twice (baseline and 5-6 weeks post-nCRT). All patients underwent surgery with preservation of the sphincter 8 weeks later. (18)F-FDG PET/CT analysis was performed by visual response assessment (VRA) and semiquantitative parameters: SUVmax(baseline), SUVmean(baseline), MTV(baseline), TLG(baseline), SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), TLG(post-nCRT); ΔSUVmax and mean and Response indexes (RImax% and RImean%). Assessment of nCRT tumor response was performed according to the Mandard's Tumor Regression Grade (TRG) and (y)pTNM staging on the surgical specimens. Concordances of VRA with TRG, and with (y)pTNM criteria were evaluated by Cohen's K. Results were compared by t student test for unpaired groups. ROC curve analysis was performed. RESULTS: VRA analysis of post-nCRT (18)F-FDG PET/CT scan for the (y)pTNM outcome showed sensitivity, specificity, accuracy, PPV, and NPV of 87.5%, 66.7%, 83.8%, 92.5%, and 53.3%, respectively. Concordances of VRA with TRG and with (y)pTNM were moderate. For the outcome variable TRG, the statistical difference between responders and non-responders was significant for SUVmax(post-nCRT) and RImean%; for the outcome variable (y)pTNM, there was a significant difference for MTV(baseline), SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), RImax%, and RImean%. ROC analysis showed better AUCs: for the outcome variable TRG for SUVmax(post-nCRT), SUVmean(post-nCRT), and RImean%; for the outcome variable (y)pTNM for MTVbaseline, SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), RImax%, and RImean%. No significant differences among parameters were found. CONCLUSIONS: Qualitative and semiquantitative evaluations for (18)F-FDG PET/CT are the optimal approach; a valid parameter for response prediction has still to be established.

(18)F-FDG PET/CT contribution to diagnosis and treatment response of rhino-orbital-cerebral mucormycosis.

OBJECTIVE: Mucormycosis is an infection caused by mycetes mucorales, emerged as a life-threatening infection associated with severe morbidity and high mortality. Conventional imaging such as computed tomography (CT) and magnetic resonance imaging (MRI) are usually performed to assess mucormycosis extension, but they may present insufficiencies in their performance. CASE PRESENTATION: We present the case of a 13 years old patient with diagnosis of rhino-orbital-cerebral mucormycosis (RCM) who performed head MRI and [(18)F]2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) both for the infection spread assessment and for the early evaluation of response to systemic amphotericin-B treatment. CONCLUSION: This case suggests that (18)F-FDG PET/CT could be considered as a valuable tool for the initial staging of RCM when compared with MRI and should be performed as soon as possible after the first clinical suspicion of this disease. In addition (18)F-FDG PET/CT may also be useful for the assessment of response to treatment.

Diagnostic and prognostic value of 18F-FDG PET/CT in comparison with morphological imaging in primary adrenal gland malignancies - a multicenter experience.

OBJECTIVE: To evaluate the diagnostic and prognostic role of fluorine-18 fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in comparison to morphological imaging such as computed tomography in primary adrenal malignancies. MATERIALS AND METHODS: In this multicenter retrospective study, 68 patients with adrenal malignancy were included. All patients had histologically proven diagnosis of primary adrenal malignancy (adrenocortical carcinoma, malignant pheochromocytoma, neuroblastoma and lymphoma), one whole body (18)F-FDG PET/CT scan and one whole-body contrast enhancement computed tomography (CECT) scan acquired within one month and were followed clinically and by performing morphological tests for at least 12 months. RESULTS: Overall sensitivity, specificity, accuracy, positive and negative predictive values for CECT and (18)F-FDG PET/CT were respectively, 59%, 100%, 65%, 100%, 27% and 75%, 100%, 82%, 100% and 63%. For adrenocortical carcinomas, (18)F-FDG PET/CT showed a better accuracy (93.4%) than CECT (75%). For neuroblastomas (18)F-FDG PET/CT also showed better accuracy (70.4%) than CECT (66.7%). For malignant pheochromocytomas (18)F-FDG PET/CT and CECT showed the same accuracy (90%). For primary adrenal lymphomas, (18)F-FDG PET/CT showed better accuracy (100%) than CECT (74.41%). Kaplan-Mayer curves showed that "histotypes" and "metastases at the last follow-up" were similarly detected for both disease free survival (DFS) and overall survival (OS), while "global 18F-FDG PET/CT" and "presence of metastases at diagnosis" were significant for DFS. Stratifying the sample by the presence or absence of metastases at diagnosis, standardized uptake value (SUVmax) was a significant prognostic factor for DFS when metastases were absent (Wald test=7.035, P=0.008). CONCLUSION: Our multicenter study demonstrated that (18)F-FDG PET/CT better than CECT diagnosed adrenal malignancies achieving also a good prognostic performance. Therefore management algorithms should include (18)F-FDG PET/CT.

Current clinical use of 18FDG-PET/CT in patients with thoracic and systemic sarcoidosis.

PURPOSE: This study assessed the role of whole-body (18)fluorodeoxyglucose positron-emission tomography/computed tomography ((18)FDG PET/CT) in the restaging and follow-up of patients with sarcoidosis previously studied by multidetector computed tomography (MDCT). MATERIALS AND METHODS: This retrospective study enrolled 21 patients to evaluate the sensitivity, specificity and accuracy of (18)FDG-PET/CT and MDCT. The results of the two techniques were compared with the Mc Nemar test. Cohen's K was used to compare concordance at the different lesion sites. RESULTS: The sensitivity, specificity and accuracy of (18)FDG-PET/CT were 80, 66.67, and 76.19 %, respectively. The sensitivity, specificity and accuracy of MDCT were 93.33, 33.33, and 76.19 %, respectively. In 16 patients who underwent whole-body MDCT, the sensitivity, specificity and accuracy values were 91.67, 81.25, and 50 % (MDCT) and 100, 50, and 87.5 % ((18)FDG-PET/CT). CONCLUSIONS: (18)FDG-PET/CT is useful in evaluating the extent of sarcoidosis and recognising lesions at different sites, including lymph nodes, lungs, liver, spleen and bone. It also improves the interpretation of the morphological lesions seen on MDCT and depicts a larger number of lesions. Therefore, (18)FDG-PET/CT could be used to complement other more traditional techniques for the restaging and follow-up in patients with sarcoidosis.

Whole body magnetic resonance with diffusion weighted sequence with body signal suppression compared to (18)F-FDG PET/CT in newly diagnosed lymphoma.

Lymphomas are a heterogeneous group of lymphoid malignancies, which can be broadly divided into non-Hodgkin Lymphomas (NHL) and Hodgkin lymphoma (HL) that display different patterns of biological behavior and response to treatment. Their incidence is still increasing and for this reason they require a lot of effort in scientific research. The management of both NHL and HL follows well-established guidelines based on the initial staging assessment. Therefore an accurate staging is the basis for the selection of an appropriate therapeutic approach in order to prevent over or under treatment as well as to minimize morbidity related to the radio-chemotherapy regimens given. (18)F-FDG-PET is currently regarded as the reference standard imaging modality in the staging of the majority of lymphoma type, for evaluation of distribution of the disease by providing both functional and anatomic information in a single whole body examination. In particular its role is established in HL and high-grade NHL, confirmed also in Follicular Lymphoma, but its impact on the other histotypes remains to be demonstrated. Among the diagnostic tools currently available for a bio-molecular imaging assessment, of great interest is the Whole Body-Magnetic Resonance with DWIBS sequence (WB-MR/DWIBS), an emerging and promising functional whole body imaging modality to evaluate oncologic and non-oncologic lesions, resulting in images that remarkably resemble (18)F-FDG PET/CT studies. In our research study we evaluated the role of WB-MR/DWIBS, compared with (18)F-FDG-PET/CT in the initial staging of lymphomas, considering its impact on the management of these patients and how it could influence the therapeutic choice. We prospectively enrolled 27 consecutive patients with newly diagnosed lymphoma (13 HL, 14 NHL) histologically proven, who underwent (18)F-FDG-PET/CT and WB-MR/DWIBS (coronal T1-weighted, coronal STIR, axial sequences DWIBS) within 10 days from the diagnosis and before start the treatment. We evaluated the overall agreement between the two methods, the general agreement in evaluating both nodal and extra-nodal involvement and a specific site agreement according to lymph nodal basins or extra-nodal sites involvement. The agreement between the two diagnostic tools in relation to histological types (HL/NHL) and in relation to indolent and aggressive forms, within NHL histotypes, as well as in relation to the Ann Arbor stage was also evaluated. We also analyzed the role of WB-MRI/DWIBS and (18)F-FDG-PET/CT in bone marrow involvement detection by calculating their sensitivity and specificity, with bone marrow biopsy as the reference standard, and comparing them with McNemar test. A total of 85 lesions, nodal (74) and extra-nodal (11), were detected by (18)F-FDG-PET/CT. WB-MRI/DWIBS showed a total of 91 sites involved, (81) nodal and (13) extra-nodal lesions. The overall agreement between the two imaging modalities was very good (k=0.815; IC:0.739-0.890); however considering histotypes, the agreement comes down to good in evaluating NHL for both nodal and extra-nodal involvement (k=0.763, IC: 0.627-0.898; k=0.629, IC:-0.021-1.278). Considering indolent or aggressive forms the agreement between WB-MR/DWIBS and (18)F-FDG PET/CT findings was very good in aggressive forms while it appeared to be lower in indolent forms. Sensitivity and specificity of WB-MRI/DWIBS and (18)F-FDG PET/CT in bone marrow involvement detection were respectively: 100%and 100% vs. 50% and 96%. The switch from (18)F-FDG PET/CT to WB-MR/DWIBS in the AA Staging System resulted in an over-staging in 1/27 patient. The two methods were concordant in the staging in 26/27 patients (96%). In conclusion, our initial results show a good overall agreement between the two diagnostic tools. (18)F-FDG-PET/CT remains the gold standard for lymphoma staging, however WB-MRI/DWIBS can be useful in histotypes not (18)F-FDG-avid or in the evaluation of "critical" organs for (18)F-FDG PET/CT. The integrated information provided by metabolic and tissutal functional imaging can be complementary to assist hematologic decision of tailored patient's treatment.

Useful diagnostic biometabolic data obtained by PET/CT and MR fusion imaging using open source software.

In the last decade numerous attempts were considered to co-register and integrate different imaging data. Like PET/CT the integration of PET to MR showed great interest. PET/MR scanners are recently tested on different distrectual or systemic pathologies. Unfortunately PET/MR scanners are expensive and diagnostic protocols are still under studies and investigations. Nuclear Medicine imaging highlights functional and biometabolic information but has poor anatomic details. The aim of this study is to integrate MR and PET data to produce distrectual or whole body fused images acquired from different scanners even in different days. We propose an offline method to fuse PET with MR data using an open-source software that has to be inexpensive, reproducible and capable to exchange data over the network. We also evaluate global quality, alignment quality, and diagnostic confidence of fused PET-MR images. We selected PET/CT studies performed in our Nuclear Medicine unit, MR studies provided by patients on DICOM CD media or network received. We used Osirix 5.7 open source version. We aligned CT slices with the first MR slice, pointed and marked for co-registration using MR-T1 sequence and CT as reference and fused with PET to produce a PET-MR image. A total of 100 PET/CT studies were fused with the following MR studies: 20 head, 15 thorax, 24 abdomen, 31 pelvis, 10 whole body. An interval of no more than 15 days between PET and MR was the inclusion criteria. PET/CT, MR and fused studies were evaluated by two experienced radiologist and two experienced nuclear medicine physicians. Each one filled a five point based evaluation scoring scheme based on image quality, image artifacts, segmentation errors, fusion misalignment and diagnostic confidence. Our fusion method showed best results for head, thorax and pelvic districts in terms of global quality, alignment quality and diagnostic confidence,while for the abdomen and pelvis alignement quality and global quality resulted poor due to internal organs filling variation and time shifting beetwen examinations. PET/CT images with time of flight reconstruction and real attenuation correction were combined with anatomical detailed MRI images. We used Osirix, an image processing Open Source Software dedicated to DICOM images. No additional costs, to buy and upgrade proprietary software are required for combining data. No high technology or very expensive PET/MR scanner, that requires dedicated shielded room spaces and personnel to be employed or to be trained, are needed. Our method allows to share patient PET/MR fused data with different medical staff using dedicated networks. The proposed method may be applied to every MR sequence (MR-DWI and MR-STIR, magnet enhanced sequences) to characterize soft tissue alterations and improve discrimination diseases. It can be applied not only to PET with MR but virtually to every DICOM study.

Role of 18F-FCH PET/CT in Detecting Recurrences of Prostate Cancer After Curative Treatments.

Objectives: To evaluate the role of 18F-fluorocholine (18F-FCH) positron emission tomography/computed tomography (PET/CT) in prostate cancer (PC) patients with biochemical recurrence who were submitted to different curative treatments. Methods: Seventy-five patients with PC who underwent 18F-FCH PET/CT for biochemical recurrence were retrospectively analyzed to distinguish patients who were submitted only to prostatectomy (PR group), only to radiotherapy (RT) on prostate with curative intent (RT group), and to both (PR + RT group). Correlations between 18F-FCH PET/CT and outcome and between prostate-specific antigen (PSA) values and sites and the number of metastases were analyzed. The performance of 18F-FCH PET/CT in relation to the PSA value and of maximum standardized uptake value (SUVmax) value in relation to patient outcome were assessed by receiver operating characteristic (ROC) curves. Results: 18F-FCH PET/CT relapses mostly involved lymph nodes, bones, and prostate bed. K-cohen test showed moderate agreement with the outcome in the whole population and in the PR group, whereas in the RT group it was perfect and in PR + RT fair. A statistically significant difference in PSA values was observed in the presence of lymph node metastases and with multiple metastases. ROC curves showed PSA cut-off values of 1.96 ng/dL, 1.95, 1.81, and 2.96, respectively, in the whole population, PR, RT and PR + RT group. SUVmax cut-off values of 3.75, 3.45, and 4.7 were described in the whole population, PR group, and PR + RT group. Conclusion: The study confirms that 18F-FCH PET/CT is still valid in PC patients with suspected biochemical recurrence. Therefore, we can affirm that it still makes sense to perform it both with high PSA values and with lower values when prostate-specific membrane antigen tracers are not available.

The Role of the 18F-FDG PET/CT in the Management of Patients Suspected of Cardiac Implantable Electronic Devices' Infection.

Background: Infection of Cardiac Implantable Electronic Devices (CIEDI) is a real public health problem. The main aim of this study was to determine the diagnostic performance of 18F-FDG PET/CT in the diagnosis of CIEDI. Methods: A total of 48 patients, who performed 18F-FDG PET/CT for the clinical suspicion of CIEDI were retrospectively analyzed; all patients were provided with a model with procedural recommendations before the exam. Sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy (DA) of 18F-FDG PET/CT were calculated; the reproducibility of qualitative analysis was assessed with Cohen's κ test. The semi-quantitative parameters (SUVmax, SQR and TBR) were evaluated in CIEDI+ and CIEDI- patients using the Student' t-test; ROC curves were elaborated to detect cut-off values. The trend of image quality with regards to procedural recommendation adherence was evaluated. Results: Se, Sp, PPV, NPV and DA were respectively 96.2%, 81.8%, 86.2%, 94.7% and 89.6%. The reproducibility of qualitative analysis was excellent (K = 0.89). Semiquantitative parameters resulted statistically different in CIEDI+ and CIEDI- patients. Cut-off values were SUVmax = 2.625, SQR = 3.766 and TBR = 1.29. Trend curves showed increasing image quality due to adherence to procedural recommendations. Conclusions:18F-FDG-PET/CT is a valid tool in the management of patients suspected of CIEDI and adherence to procedural recommendations improves its image quality.

[18F-FDG PET/CT in staging and restaging cholangiocarcinoma]. / La PET/TC con 18F-FDG nella stadiazione, diagnosi e ristadiazione del colangiocarcinoma.

The prognosis for hepatobiliary malignancies is dismal. Surgery remains the primary curative option. The positron emission tomography/computed tomography (PET/CT) provides simultaneous metabolic and anatomic information on tumors in the same imaging session. The role of PET/CT in detecting hepatobiliary malignancies has not yet been established. The purpose of this review was to examine the literature on the use of PET/CT in cholangiocarcinomas, also in order to improve the preoperative staging and the restaging, for a proper oncology management of patients.

[18F-FDG PET/CT in a patient with clinical suspicion of giant cell arteritis]. / La gestione di un caso di arterite a cellule giganti con la 18F-FDG PET/TC.

We report the case of a 72 year old man with clinical suspicion of giant cell arteritis (GCA); in this case 18F-FDG PET/CT has been useful from the diagnosis to the control of the response to therapy. He performed the first 18F-FDG PET/CT that showed increased uptake of 18F-FDG in the aortic arch, brachial artery, common iliac and femoral arteries and in the temporal cerebral sites bilaterally. The patient then began a cortisonic therapy that led straight to the improvement of clinical symptoms, and repeated 18F-FDG PET/CT 3 months later the beginning of therapy that showed reduced uptake in the same sites of the first 18F-FDG PET/CT. This patient continued the cortisonic therapy, progressively reducing it until the definitive ending.

[Correlation between cognitive impairment and plasma levels of clusterin/ApoJ in Parkinson disease patients not affected by dementia]. / Correlazione tra deterioramento cognitivo e livello plasmatico della clusterina/ApoJ in pazienti con malattia di Parkinson non affetti da demenza.

Cognitive impairment is frequent in patients with Parkinson's disease (PD), and can range from mild deterioration to dementia. Recently a contribution of Alzheimer's disease for the cognitive dysfunction in PD has been proposed, whereas the presence of tau protein and amyloid was recognized. Clusterin/ApoJ is a protein involved in the deposition of beta-amyloid and in its neurotoxicity. In this study we aimed to investigate the clusterin/ApoJ's plasma levels in patients with PD to assess its potential role in fisiopathogenetic cognitive impairment.