Optimization of the exposure parameters in digital mammography using contrast-detail metrics

PurposeOptimization studies in digital mammography aid to assure the image quality and radiological protection of the patient. The aim of this work is to test effectiveness and applicability of a method based on a Figure of Merit (FOM = (IQF_inv)²/AGD) to improve all the exposure parameters (Target/Filter combination, kVp and mAs) in order to improve the image acquisition technique that will provide the best compromise between image quality and the average glandular dose (AGD).MethodsA contrast-detail analysis, employing the test object CDMAM, was carried out for the digital mammography unit manufactured by Lorad Hologic – model Selenia. We simulated two breast thicknesses using phantoms and a Figure of Merit as optimization tool, which includes an indicator of image quality, the IQF_inv and the average glandular dose. Images of the ACR and TORMAM phantoms were obtained with both, automatic and optimized exposure parameters. In order to compare the image quality, the SNR (Signal to Noise Ratio) was measured in each image.ResultsIn the two phantoms, for both 4.5 and 7.5 cm thicknesses, the AGDs obtained with the optimized parameters show a reduction. In addition, the images obtained with the optimized exposure parameters, had the same or a better image quality when compared to the images obtained using the automatic mode.ConclusionsThe proposed optimization methodology proved to be an effective tool to improve the digital mammography unit, due to the use of objective metrics for evaluation and validation of the results.     

乳腺导管上皮内瘤变32 例影像诊断分析

目的:探讨全数字化乳腺X线摄影与磁共振成像检查相结合对乳腺导管上皮内瘤变(DIN)的诊断价值。方法:对32例经乳腺平板数字X线摄影及磁共振检查并且病理证实为乳腺导管上皮内瘤变的病例进行回顾性分析。结果:32例DIN中,普通导管上皮增生(UDH)17例,DIN1A 2例;DIN1B 1例;乳腺导管原位癌(DIN1C-DIN3)12例。采用全数字化X线乳腺摄影与MRI相结合诊断乳腺增生18例,乳腺导管原位癌11例,3例未能明确诊断。结论:平板数字X线乳腺摄影及磁共振成像综合诊断,对乳腺导管原位癌的早期发现具有重要意义,显著提高患者的生存质量。     

洪堡大学Virchow后期临床教学医院和Robert—Rssle医院的外科和肿瘤外科系的研究概况

简要介绍了位于柏林的洪堡大学Ｖｉｒｃｈｏｗ后期临床教学医院的Ｒｏｂｅｒｔ—Ｒｏｓｓｌｅ医院的外科和肿瘤外科系的概况和与激光有关的研究项目。     

Automatic diagnosis of mammographic abnormalities based on hybrid features with learning classifier

Breast cancer screening is currently performed by mammography, which is limited by overlying anatomy and dense breast tissue. Computer-aided detection (CAD) systems can serve as a double reader to improve radiologist performance. In this paper, we have applied a novel approach to segmentation of suspicious region by mammogram and classification based on hybrid features with learning classifier. We formulated differentiation of lesion from normal tissue as a supervised learning problem, and applied this learning method to develop the classification algorithm. The algorithm has been verified with 164 mammograms in the mini Mammographic Image Analysis Society database. The experimental results show that the detection method has a sensitivity of 94.5% at 0.26 false positives per image. The efficiency of algorithm is measured using free receiver operating characteristics curve and the results are highlighted. We conclude that CAD technology with learning classifier has the potential to help radiologists with the task of discriminating between lesion and normal tissues.     

全数字化乳腺X线摄影诊断临床隐匿型乳腺癌的价值

目的：探讨全数字化乳腺X线摄影对临床隐匿性乳癌的诊断价值。方法：回顾性分析临床扪诊阴性,手术病理证实乳腺癌12例。全部病例均使用全数字化乳腺X线摄影。结果：12例病例发现病灶12个,其中单纯钙化7例,微结节或结构紊乱伴微钙化3例,微结节伴毛刺11例。局部结构紊乱1例。结论：全数字化乳腺X线摄影能清晰显示乳房各个层次结构,尤其发现恶性钙化敏感性高,对发现临床隐匿型乳腺癌具有重大价值。     

乳腺导管上皮内瘤变32例影像诊断分析

目的：探讨全数字化乳腺X线摄影与磁共振成像检查相结争对乳腺导管上皮内瘤变（DIN）的诊断价值。方法：对32例经乳腺平板数字X线摄影及磁共振检查并且病理证实为乳腺导管上皮内瘤变的病例进行回顾性分析。结果：32例DIN中,普通导管上皮增生（UDH）17例,DIN1A2例;DIN1B1例;乳腺导管原位癌（DIN1C--DIN3）12例。采用全数字化X线乳腺摄影与MRI相结合诊断乳腺增生18例,乳腺导管原位癌11例,3例未能明确诊断。结论：平板数字X线乳腺摄影及磁共振成像综合诊断,对乳腺导管原位癌的旱期发现具有重要意义．显著提高患者的生存质量。     

数字乳房X片图像的预处理算法研究

介绍了一种数字乳房X片图像的预处理算法。利用时域处理和形态学处理相结合的方法,对数字乳房X片图像进行预处理,去除无用背景像素点,有效减少后期增强、分割处理的数据量。     

Quality Controls in Digital Mammography protocol of the EFOMP Mammo Working group

This article aims to present the protocol on Quality Controls in Digital Mammography published online in 2015 by the European Federation of Organisations for Medical Physics (EFOMP) which was developed by a Task Force under the Mammo Working Group. The main objective of this protocol was to define a minimum set of easily implemented quality control tests on digital mammography systems that can be used to assure the performance of a system within a set and acceptable range. Detailed step-by-step instructions have been provided, limiting as much as possible any misinterpretations or variations by the person performing. It is intended that these tests be implemented as part of the daily routine of medical physicists and system users throughout Europe in a harmonised way so allowing results to be compared. In this paper the main characteristics of the protocol are illustrated, including examples, together with a brief summary of the contents of each chapter. Finally, instructions for the download of the full protocol and of the related software tools are provided.     

全数字化乳腺X线摄影诊断临床隐匿型乳腺癌的价值

目的:探讨全数字化乳腺X线摄影对临床隐匿性乳癌的诊断价值。方法:回顾性分析临床扪诊阴性,手术病理证实乳腺癌12例。全部病例均使用全数字化乳腺X线摄影。结果:12例病例发现病灶12个,其中单纯钙化7例,微结节或结构紊乱伴微钙化3例,微结节伴毛刺1例,局部结构紊乱1例。结论:全数字化乳腺X线摄影能清晰显示乳房各个层次结构,尤其发现恶性钙化敏感性高,对发现临床隐匿型乳腺癌具有重大价值。     

ClearPEM,un TEP dédié au sein

Conventional breast imaging (mammography, ultrasound, MRI) relies on the analysis of anatomical characteristics. Whole-body positron emission tomography (PET) allows for the acquisition of a metabolic image, yet is limited by its poor spatial resolution. The Crystal Clear Collaboration developed a PET dedicated for breast imaging, the ClearPEM, in order to offer a high-resolution nuclear imaging technique. The patient is installed in the prone position on the exam bed, with two detector plates rotating around to breast to acquire a 3-dimensional image. Two prototypes were built and installed in hospitals. We summarize the technical solutions necessary for the development of this system and present a summary of its performances as well as an outlook on preclinical and clinical tests.