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Marseille, France

Bouwman R.W.,Radboud University Nijmegen | Visser R.,Radboud University Nijmegen | Young K.C.,University of Surrey | Dance D.R.,University of Surrey | And 4 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2010

Breast tomosynthesis is an imaging modality that recently became available for breast examination. For conventional Projection mammography qualify control procedures are well described. For breast tomosynthesis on the other hand, Such procedures hate not yet been established. In this paper we propose a simple method and phantom for daily quality control (DQC). With DQC image quality problems arising after acceptance of the system should be detected. Therefore, the DQC procedure needs to monitor the stability of the most critical components of the system over tune. For breast tomosynthesis we assume that the most critical items are the image receptor, X-ray tube and the tomosynthesis motion. The proposed procedure the image receptor homogeneity and system stability are evaluated using an image of a homogeneous block of PMMA. The z-resolution is assumed to be dependent on the tomosynthesis motion. To momtor this motion the nominal z-resolution using the slice sensitive profile is measured Shading artefacts that arise due to objects with high attenuation are also typical for tomosynthesis systems. Analysing those artefacts may provide additional information about the tomosynthesis motion. The proposed DQC procedure has been evaluated on two Afferent breast tomosynthesis systems: A multi slit scanning system and a system using a stationary a-Se detector. Preliminary results indicate that the proposed method is useful for DQC, although some minor advised. To verify that this method detects image quality problems sufficiently, more experience with different DBT systems, over longer periods of time are needed. © 2010 SPIE. Source

Van Engen R.E.,National Expert and Training Center for Breast Cancer Screening | Bosmans H.,University Hospitals Leuven | Bouwman R.W.,National Expert and Training Center for Breast Cancer Screening | Dance D.R.,National Coordinating Center for the Physics of Mammography | And 7 more authors.
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

Quality control (QC) procedures for digital breast tomosynthesis (DBT) systems are a crucial part of the acceptance of a new modality. In contrast to the situation in the US, the European approach is to provide a device independent protocol with limiting values that should be applied to all systems. A European QC protocol that deals with this challenge is being developed and is currently work-in-progress. In this paper four specific QC tests for DBT, which have reached an (almost) final stage, are presented: reproducibility, system projection MTF, z-resolution and missed tissue at the top and bottom of the reconstructed volume. The proposed tests have been evaluated on several DBT systems. The encouraging results show that these tests will form an appropriate and necessary part of QC procedures for DBT. © 2014 Springer International Publishing. Source

Tamalet C.,Marseille University Hospital Center | Le Retraite L.,Arcades | Leandri F.-X.,Arcades | Heid P.,Arcades | And 2 more authors.
Clinical Microbiology and Infection | Year: 2013

In France, about 40% of women aged 25-65 years do not participate in regular screening and thus are at high risk (HR) of cervical cancer. Human papillomavirus (HPV) vaginal self-sampling is a valuable alternative in this population. This study aimed to assess the prevalence of HR and LR (low-risk) HPV infection in 3767 women aged >35 years from mid-socioeconomic backgrounds who carried out HPV vaginal self-sampling at home. HPV vaginal self-sampling was better accepted than the Pap-test in women aged 35-69 years who were previously non-responders to individual invitation. From the 933 self-collected swabs studied (24.7%), 62 were HPV-infected (6.6%), and 73 HPV types were found. HPV 16 was the most frequently found (43.5%), followed by 53 (23.2%), 18 (12.3%), 66 (12.3%), 31 (6.8%), 33 (5.4%) and 58 (2.7%). Ten women (16.2%) were infected by multiple HR-HPV types. Median HPV 16 load was 104.000 copies/106 cells and median HPV 18 load was 833 copies/106 cells. Six women (9.3%) harboured LR-HPV types. The 12-month follow-up of 43 HR-HPV positive women (69.3%) revealed CIN2-3 lesions in three women (6.9%), all HPV 16 infected, and harbouring an HPV 16 load >5 log10 copies/106 cells. Women harbouring HR-HPV types other than HPV 16/18 were older than women harbouring HPV 16/18 types (55 years vs. 46.9 years, p 0.0008). The high frequency of HR-HPV types in women >50 years deserves further investigation to elucidate the mechanism involved (re-infection or reactivation). © 2012 The Authors Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases. Source

Sancho-Garnier H.,Regional Cancer Center | Tamalet C.,Virology Unit | Halfon P.,Alphabio Laboratory | Leandri F.X.,Arcades | And 5 more authors.
International Journal of Cancer | Year: 2013

Today in France, low attendance to cervical screening by Papanicolaou cytology (Pap-smear) is a major contributor to the 3,000 new cervical cancer cases and 1,000 deaths that occur from this disease every year. Nonattenders are mostly from lower socioeconomic groups and testing of self-obtained samples for high-risk Human Papilloma virus (HPV) types has been proposed as a method to increase screening participation in these groups. In 2011, we conducted a randomized study of women aged 35-69 from very low-income populations around Marseille who had not responded to an initial invitation for a free Pap-smear. After randomization, one group received a second invitation for a free Pap-smear and the other group was offered a free self-sampling kit for HPV testing. Participation rates were significantly different between the two groups with only 2.0% of women attending for a Pap-smear while 18.3% of women returned a self-sample for HPV testing (p ≤ 0.001). The detection rate of high-grade lesions (≥CIN2) was 0.2‰ in the Pap-smear group and 1.25‰ in the self-sampling group (p = 0.01). Offering self-sampling increased participation rates while the use of HPV testing increased the detection of cervical lesions (≥CIN2) in comparison to the group of women receiving a second invitation for a Pap-smear. However, low compliance to follow-up in the self-sampling group reduces the effectiveness of this screening approach in nonattenders women and must be carefully managed. Copyright © 2013 UICC. Source

Tamalet C.,Center Hospitalo University Timone | Richet H.,Center Hospitalo University Timone | Carcopino X.,Service de gynecologie obstetrique | Henry M.,Center Hospitalo University Timone | And 5 more authors.
Journal of Medical Virology | Year: 2010

Self-sampling using vaginal swabs could be a valuable alternative to screen for cervical cancer for women who do not attend regular cytological screening. The aim of this study was to determine the prevalence of high and low-risk HPV types and of HPV type 16 and 18 DNA load in self-collected vaginal swabs from 35- to 69-year-old Southern French women of low socioeconomic level or migrant populations who do not attend regular cervical screening. A good concordance (93.1%) was found between cervical brush and vaginal swabs in 29 samples. Self-collected vaginal swabs were examined from 120 women. HPV infection was found in 28 women (23.3%; median age 48 years), 17 (14.1%) of whom harbored high-risk HPV types. HPV type 16 was the high risk type found most frequently, followed by types 53, 31, 18, 58, and 66. The low-risk type detected most frequently was HPV type 6, followed by types 61, 70, and 81. The mean HPV 16 and 18 load was 6.3 log10 copies/106 cells and 2.4 log 10 copies/106 cells, respectively. These results suggest that vaginal self-swabs can be a reliable tool for cervical cancer screening in non-attending and inadequately screened elderly women. © 2010 Wiley-Liss, Inc. Source

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