Increase in perceived case suspiciousness due to local contrast optimisation in digital screening mammography

Item does not contain fulltextOBJECTIVES: To determine the influence of local contrast optimisation on diagnostic accuracy and perceived suspiciousness of digital screening mammograms. METHODS: Data were collected from a screening region in the Netherlands and consisted of 263 digital screening cases (153 recalled,110 normal). Each case was available twice, once processed with a tissue equalisation (TE) algorithm and once with local contrast optimisation (PV). All cases had digitised previous mammograms. For both algorithms, the probability of malignancy of each finding was scored independently by six screening radiologists. Perceived case suspiciousness was defined as the highest probability of malignancy of all findings of a radiologist within a case. Differences in diagnostic accuracy of the processing algorithms were analysed by comparing the areas under the receiver operating characteristic curves (A(z)). Differences in perceived case suspiciousness were analysed using sign tests. RESULTS: There was no significant difference in A(z) (TE: 0.909, PV 0.917, P = 0.46). For all radiologists, perceived case suspiciousness using PV was higher than using TE more often than vice versa (ratio: 1.14-2.12). This was significant (P <0.0083) for four radiologists. CONCLUSIONS: Optimisation of local contrast by image processing may increase perceived case suspiciousness, while diagnostic accuracy may remain similar. KEY POINTS: Variations among different image processing algorithms for digital screening mammography are large. Current algorithms still aim for optimal local contrast with a low dynamic range. Although optimisation of contrast may increase sensitivity, diagnostic accuracy is probably unchanged. Increased local contrast may render both normal and abnormal structures more conspicuous.1 april 201

One-day core needle biopsy in a breast clinic: 4 years experience

Contains fulltext : 118897pub.pdf (publisher's version ) (Closed access) Contains fulltext : 118897pos.pdf (postprint version ) (Open Access)Many attempts have been made to combine the high diagnostic accuracy and conclusive rate of core needle biopsy (CNB) with the speed of fine needle aspiration cytology in evaluation of solid breast lesions. Multiple hybrid techniques have been developed to achieve this. We describe a cohort of patients for whom we used a relatively new, accelerated method of CNB processing, allowing for a definitive diagnosis the same day. All patients visiting the Radboud University Nijmegen Medical Centre breast clinic during a 4-year period were reviewed to identify all CNBs in this period performed in a same-day diagnosis track. CNB result was compared to post-operative pathology reports when available, and to follow-up when patients were not surgically treated. 1,060 patients underwent CNB of 1,383 lesions, 898 of which in a same-day diagnosis track with a sensitivity of 96.9 % and a specificity of 99.4 %. The inconclusive rate was 9.2 %. For a same-day diagnosis for solid breast lesions, we could give a conclusive diagnosis with accelerated CNB processing in 65 % of our patients requiring CNB. This technique can be used reliably in a same-day diagnosis breast clinic with a very high sensitivity, specificity, and conclusive rate

Standalone computer-aided detection compared to radiologists' performance for the detection of mammographic masses

Item does not contain fulltextOBJECTIVES: We developed a computer-aided detection (CAD) system aimed at decision support for detection of malignant masses and architectural distortions in mammograms. The effect of this system on radiologists' performance depends strongly on its standalone performance. The purpose of this study was to compare the standalone performance of this CAD system to that of radiologists. METHODS: In a retrospective study, nine certified screening radiologists and three residents read 200 digital screening mammograms without the use of CAD. Performances of the individual readers and of CAD were computed as the true-positive fraction (TPF) at a false-positive fraction of 0.05 and 0.2. Differences were analysed using an independent one-sample t-test. RESULTS: At a false-positive fraction of 0.05, the performance of CAD (TPF?=?0.487) was similar to that of the certified screening radiologists (TPF?=?0.518, P?=?0.17). At a false-positive fraction of 0.2, CAD performance (TPF?=?0.620) was significantly lower than the radiologist performance (TPF?=?0.736, P <0.001). Compared to the residents, CAD performance was similar for all false-positive fractions. CONCLUSIONS: The sensitivity of CAD at a high specificity was comparable to that of human readers. These results show potential for CAD to be used as an independent reader in breast cancer screening. KEY POINTS : � Computer-aided detection (CAD) systems are used to detect malignant masses in mammograms � Current CAD systems operate at low specificity to avoid perceptual oversight � A CAD system has been developed that operates at high specificity � The performance of the CAD system is approaching that of trained radiologists � CAD has the potential to be an independent reader in screening