Typical values of z-resolution for different Digital Breast Tomosynthesis systems evaluated in a multicenter study

PURPOSE

The aim of the present study, conducted by a working group of the Italian Association of Medical Physics (AIFM), was to define typical z-resolution values for different digital breast tomosynthesis (DBT) models to be used as a reference for quality control (QC). Currently, there are no typical values published in internationally agreed QC protocols.

METHODS

To characterize the z-resolution of the DBT models, the full width at half maximum (FWHM) of the artifact spread function (ASF), a technical parameter that quantifies the signal intensity of a detail along reconstructed planes, was analyzed. Five different commercial phantoms, CIRS Model 011, CIRS Model 015, Modular DBT phantom, Pixmam 3-D, and Tomophan, were evaluated on reconstructed DBT images and 82 DBT systems (6 vendors, 9 models) in use at 39 centers in Italy were involved.

RESULTS

The ASF was found to be dependent on the detail size, the DBT angular acquisition range, the reconstruction algorithm and applied image processing. In particular, a progressively greater signal spread was observed as the detail size increased and the acquisition angle decreased. However, a clear correlation between signal spread and angular range width was not observed due to the different signal reconstruction and image processing strategies implemented in the algorithms developed by the vendors studied.

CONCLUSIONS

The analysis led to the identification of typical z-resolution values for different DBT model-phantom configurations that could be used as a reference during a QC program.

Surgeon eye lens dose monitoring in interventional neuroradiology, cardiovascular and radiology procedures

PURPOSE

This study investigated the radiation dose to surgeon eye lens for single procedure and normalised to exposure parameters for eight selected neuroradiology, cardiovascular and radiology interventional procedures.

METHODS

The procedures investigated were diagnostic study, Arteriovenous Malformations treatment (AVM) and aneurysm embolization for neuroradiology procedures, Coronary Angiography and Percutaneous Transluminal Coronary Angioplasty (CA-PTCA), Pacemaker and Implantable Cardioverter-Defibrillator implantation (PM-ICD), Endovascular Aortic Repair (EVAR) and Fenestrated Endovascular Aortic Repair (FEVAR) for cardiovascular and electrophysiology procedures. CT-guided lung biopsy was also monitored. All procedures were performed with table-mounted and ceiling-suspended shields (0.5 mm lead equivalent thickness), except for FEVAR and PM-ICD where only a table mounted shield was present, and CT-guided lung biopsy where no shield was used. Dose assessment was performed using a dosemeter positioned close to the most exposed eye of the surgeon, outside the protective eyewear.

RESULTS

The surgeon most exposed eye lens median H_p(3) equivalent dose for a single procedure, without protective eyewear contribution, was 18 μSv for neuroradiology diagnostic study, 62 μSv for AVM, 38 μSv for aneurysm embolization, 33 μSv for CA-PTCA, 39 μSv for PM-ICD, 49 μSv for EVAR, 2500 μSv for FEVAR, 153 μSv for CT-guided lung biopsy.

CONCLUSIONS

In interventional procedures, the 20 mSv/year dose limit for surgeon eye lens exposure might be exceeded if shields or protective eyewear are not used. Surgeon eye lens doses, normalised to single procedures and to exposure parameters, are a valuable tool for determining appropriate radiation protection measures and dedicated eye lens dosemeter assignment.

Epidemiological and Virological Assessment of Influenza Activity in Apulia, Italy, during the Seasons 2004–2005 and 2005–2006

This study evaluated the impact of influenza and vaccination coverage in Apulia, Italy, during the 2004–2005 and 2005–2006 seasons, using epidemiological and virological surveillance data collected through the Italian Net of Surveillance of Influenza (InfluNet) organized by the Superior Institute of Health (ISS) and the Inter-University Centre of Research on Influenza (CIRI). Vaccination coverage was calculated from the number of doses administered to individuals aged ≤ 65 years. Sentinel physicians reported weekly influenza-like illness (ILI) and acute respiratory illness (ARI) occurrences among patients. Influenza viruses were isolated and identified by cell culture on Madin-Darby Canine Kidney cells and polymerase chain reaction techniques. Vaccination coverage reached 72.7% and 77.0% during the 2004–2005 and 2005–2006 seasons, respectively. Incidence of ILI was higher during the 2004–2005 season compared with the 2005–2006 season, whereas the incidence ARI appeared to show a more constant trend. Incidence rates for ILI and ARI were higher in the 0 − 14-year age group. The increase in vaccination coverage and implementation of a network of epidemiological and virological surveillance are fundamental for the control and prevention of influenza.

Direct Detection of Bordetella pertussis and Bordetella parapertussis: Comparison of Polymerase Chain Reaction and Culture

We evaluated the diagnostic performance of a genomic DNA amplification method for Bordetella pertussis and Bordetella parapertussis compared with culture isolation. Aliquots from B. pertussis and B. parapertussis cultures were added to sterile physiological saline or sterile distilled water to give bacterial suspensions of 108 cells/ml and serial dilutions were prepared. Suspensions in physiological saline were cultured on charcoal agar medium; bacterial growth was observed up to dilutions of 10−7. Suspensions in distilled water were subjected to DNA extraction and nested polymerase chain reaction (PCR) was performed on the extracts; the PCR was positive up to dilutions of 10−8 for B. pertussis and 10−9 for B. parapertussis. Since the efficacy of culture isolation, regarded as the standard for the detection of B. pertussis and B. parapertussis, declines after the first stage of pertussis or with prior vaccination or antibiotic therapy, PCR, although not yet standardized, may provide an alternative diagnostic tool.

Safety and Immunogenicity of Conventional Subunit and MF59-adjuvanted Influenza Vaccines in Human Immunodeficiency Virus-1-seropositive Patients

In this study of influenza vaccination, 37 human immunodeficiency virus (HIV)-1-seropositive patients were randomized to receive either a vaccine with a conventional subunit or one adjuvanted with MF59. Blood samples were collected at the time of vaccination, and then 30 and 180 days later, to evaluate immunogenicity, CD4+ T-lymphocyte count and HIV-1 RNA levels. Seroconversion rates against the three viral strains included in the vaccine ranged between 44% and 72% and 53% and 68% for the adjuvanted vaccine and the subunit vaccine, respectively. Other criteria of the European Medicines Evaluation Agency were also met. Vaccination was not associated with serious adverse events. Local and systemic effects were mild and of short duration. CD4+ T-lymphocyte counts and viraemia levels were not negatively affected by vaccination. These results confirmed the safety and immunogenicity of these currently available vaccines in HIV-1-seropositive patients, thus supporting the recommendation for influenza immunization in this high-risk category.

Molecular approaches in the diagnosis of sepsis in neutropenic patients with haematological malignances

INTRODUCTION

Sepsis is a major cause of significant morbidity and mortality in neutropenic patients. Blood culture remains the gold standard in the microbiological diagnosis of bacterial or fungal bloodstream infections, but it has clear limits of rapidity and sensitivity. The objective of the study was to compare the real-time polymerase chain reaction (RT-PCR) with automated blood cultures (BC) method in detection in whole blood of pathogens in febrile neutropenic patients with hematological malignancies.

METHODS

A total of 166 consecutive febrile neutropenic patients were enrolled. Blood samples for cultures and SeptiFast testing were obtained at the onset of fever, before the implementation of empirical antibiotic therapy.

RESULTS

Forty (24.1%) samples out of the 166 blood samples tested, were positive by at least one method. Twenty-three (13.9%) samples were positive by blood culture and 38 (22.9%) by multiplex real-time PCR. The analysis of concordance evidenced a low correlation between the two methods (n = 21; 52.5%), mainly due to samples found negative by culture but positive with the Septi-Fast assay. Sensitivity, specificity, and positive and negative predictive values of RT-PCR were 91.3%, 88.1%, 55.3%, and 98.4%, respectively, compared with BC.

DISCUSSION

Multiplex real-time PCR assay improved detection of the most bacteria associated with febrile neutropenia episodes. Further studies are needed to assess the real advantages and clinical benefits that molecular biology tests can add in diagnosis of sepsis.

Seroepidemiology of human bocavirus in Apulia, Italy

A serological survey was performed to determine the prevalence of antibodies against human bocavirus in an Apulian population. Anti-hBoV IgG antibodies were analysed in 1206 inhabitants (age range, 1month-84years) using a standardized ELISA test based on the use of recombinant hBoV VP2 virus-like particles. In total, 1075 (89.1%) of 1206 participants (mean age 32±24.8years) displayed anti-hBoV-IgG. The seroprevalence increased significantly (p<0.0001) in children from 2-4years (64.2%) to 5-9years (96.4%). A similar trend was observed in both male and female subjects. In conclusion, our results show that hBoV infection is common in this population, especially in children.

Susceptibility to varicella-zoster among pregnant women in the province of Lecce, Italy

BACKGROUND

Varicella is predominantly a childhood disease, considered a mild self-limiting disease that can have serious complications for a pregnant woman and her developing fetus.

OBJECTIVES

We investigated the susceptibility to varicella-zoster Virus (VZV) among pregnant women in the province of Lecce.

STUDY DESIGN

A cross-sectional study was carried out in Departments of Gynecology and Obstetrics of the Province of Lecce, where 539 pregnant women were recruited, and face-to-face interviews were conducted. Varicella IgG tests were performed.

RESULTS

The prevalence of varicella susceptibility among pregnant mothers was 10.6%. The prevalence of IgG antibodies increases significantly with increasing age, from 62.5% in the age group 15-19 years to 94.4% in the age group 40-49 years.

DISCUSSION

In the Italian National Vaccination Plan 2005-2007, varicella vaccine is only recommended for childbearing women. A safe and effective vaccine is available and no abnormalities have been observed among infants born to susceptible women who received varicella vaccines during pregnancy. Such a high number of susceptible women indicates that preventive and informative programs should be introduced, even among those who do not plan to become pregnant. Routine counselling, varicella IgG antibody screening and varicella vaccination should be considered if they have no history of the infection, to reduce the risk of fetal complications and the cost of healthcare associated with the infection.

Human metapneumovirus and human bocavirus associated with respiratory infection in Apulian population

We have studied the occurrence of hBoV, hMPV and InfA-B in an Apulian population with respiratory tract infections. During influenza season 2008-2009, 116 oropharingeal swabs were collected from patients affected by Influenza-Like Illness (ILI). The PCR products of hMPV M and HBoV NP-1 genes were sequenced. 78 out of 116 samples were positive for at least one respiratory virus; hBoV was detected in 53, hMPV in 22 and InfA-B in 41 out of 116 swabs. A high rate of hBoV infection in adult (18.9%) and elderly (26.4%) subjects was found. The co-infection rate was higher for hMPV (18/22 cases, 81.8%) compared to hBoV (26/53 cases, 49.1%), and InfA-B (25/41 cases, 61.0%). Co-infections were common in children. hBoV positive samples shared a high level of genetic similarity with the hBoV1 genotype, and hMPV positive samples clustered with A2 subgroup. Our results suggest that hBoV and hMPV play a role in ILI.

Surveillance of influenza in Apulia, Italy, 1999-2000, 2000-2001, 2001-2002, and 2002-2003 seasons

BACKGROUND

The objective of this study was to evaluate, within the Italian National Influenza Epidemiological and Virological Surveillance, the rate of vaccination coverage, the incidence of Influenza Like-Illness (ILI), the incidence of Acute Respiratory Illness (ARI), and to identify the virus strains circulating in Apulia from 1999 to 2003.

METHODS

Vaccination coverage rates were calculated based on the number of doses administered to individuals > 65 years of age. Every week, sentinel physicians reported ILI and ARI cases having occurred among their patients. Voluntary general practitioners (GPs) and paediatricians (Ps) collected oropharyngeal swab samples from patients suspected with ILI. Influenza viruses were isolated and identified by cell culture (MDCK cells) and RT-PCR. Virological surveillance was carried out by the ISS, in collaboration with a network of peripheral laboratories.

RESULTS

In Apulia, vaccination coverage progressively increased to 68.6% during the 2002-2003 season. The analysis of ILI cases showed higher incidence rates during the 1999-2000 and 2002-2003 seasons. ARI rates appeared to have a more constant trend. ILI and ARI incidence rates were higher in the 0-14 year age group.

CONCLUSION

The increase in vaccination coverage rates and implementation of the network of clinical, and epidemiological and virological surveillance are fundamental for the control and prevention of influenza.

[Chemical-physical and microbiological survey in groundwater of Salento]

In order to know better the groundwater quality of Salento, chemical-physical and microbiological investigations were carried out on waters collected from 31 wells chosen after a preliminary study about the hydrogeologic features of the region. The analysis, conducted once in a month within the span of a year, pointed out a widespread contamination of faecal origin, which limits the employment (drinkable, irriguous) of groundwater because of possible health implications. The results of the chemical-physical analyses show how the groundwater of Salento is "contaminated" by sea water getting into the continent and which in some areas, also owing to excessive drawings, deteriorates its quality and compromises its irriguous use.

[The modification of lipids in a secondary prevention program by general practice physicians]

This study follows a cognitive investigation about risk factor for ischemic heart disease performed in 1990 by a group of general practitioners in Pistoia, Italy. From this investigation we selected subjects with hypercholesterolemia; we also considered the association with other risk factors for ischemic heart disease. According to the frequency of risk factors subjects received a low-fat diet or diet plus cholesterol-lowering drug therapy (simvastatin). We describe changes on total cholesterol and its fractions by these therapeutic regimens.