Biomedical subjects

R Edward Hendrick

Publications and source records attributed to R Edward Hendrick.

At least 19 recordsLinked to original sources

PubMed2006

Quality control for digital mammography in the ACRIN DMIST trial: part I.

The Digital Mammography Imaging Screening Trial, conducted by the American College of Radiology Imaging Network, is a clinical trial designed to compare the accuracy of full-field digital mammography (FFDM) versus screen-film mammography in a screening population. Five FFDM systems from four manufacturers (Fischer, Fuji, General Electric, and Lorad) were employed in the study at 35 clinical sites. A core physics team devised and implemented tests to evaluate these systems. A detailed description of physics and quality control tests is presented, including estimates of: mean glandular dose, modulation transfer function (MTF), 2D noise power spectra, and signal-to-noise ratio (SNR). The mean glandular doses for the standard breast ranged from 0.79 to 2.98 mGy, with 1.62 mGy being the average across all units and machine types. For the five systems evaluated, the MTF dropped to 50% at markedly different percentages (22% to 87%) of the Nyquist limit, indicating that factors other than detector element (del) size have an important effect on spatial resolution. Noise power spectra and SNR were measured; however, we found that it was difficult to standardize and compare these between units. For each machine type, the performance as measured by the tests was very consistent, and no predictive benefit was seen for many of the tests during the 2-year period of the trial. It was found that, after verification of proper operation during acceptance testing, if systems failed they generally did so suddenly rather than through gradual deterioration of performance. Because of the relatively short duration of this study further, investigation of the long-term failure characteristics of these systems is advisable.

Algorithms↗

PubMed2006

Quality control for digital mammography: part II. Recommendations from the ACRIN DMIST trial.

The Digital Mammography Imaging Screening Trial (DMIST), conducted under the auspices of the American College of Radiology Imaging Network (ACRIN), is a clinical trial designed to compare the accuracy of digital versus screen-film mammography in a screening population [E. Pisano et al., ACRIN 6652-Digital vs. Screen-Film Mammography, ACRIN (2001)]. Part I of this work described the Quality Control program developed to ensure consistency and optimal operation of the digital equipment. For many of the tests, there were no failures during the 24 months imaging was performed in DMIST. When systems failed, they generally did so suddenly rather than through gradual deterioration of performance. In this part, the utility and effectiveness of those tests are considered. This suggests that after verification of proper operation, routine extensive testing would be of minimal value. A recommended set of tests is presented including additional and improved tests, which we believe meet the intent and spirit of the Mammography Quality Standards Act regulations to ensure that full-field digital mammography systems are functioning correctly, and consistently producing mammograms of excellent image quality.

Breast↗

PubMed2006

Classification of breast lesions with multimodality computer-aided diagnosis: observer study results on an independent clinical data set.

PURPOSE: To evaluate a computer-aided diagnosis multimodality intelligent workstation as an aid to radiologists in the interpretation of mammograms and breast sonograms. MATERIALS AND METHODS: An institutional review board approved the protocol for an observer study with signed consent, as well as the retrospective use of the mammograms, sonograms, and clinical data with waiver of consent. The HIPAA-compliant observer study was conducted with five breast radiologists and five breast imaging fellows, all of whom gave confidence ratings and patient management decisions, both without and with the computer aid, for 97 lesions that were unknown to both the observers and the computer. The performance of each observer without and with the computer aid was quantified by using four performance measures: area under the receiver operating characteristic curve (A(z)) value, partial A(z) value, sensitivity, and specificity. The statistical significance of the differences in the performance measures without and with the computer aid was determined by using a two-tailed t test for paired data. RESULTS: Use of the computer aid resulted in an improvement of the average performance of the 10 observers, as measured by means of a statistically significant increase in A(z) value (0.87-0.92; P < .001), partial A(z) value (0.47-0.68; P < .001), and sensitivity (0.88-0.93; P = .005). A statistically significant difference was not found in the specificity without and with the computer aid (0.66-0.69; P = .20). CONCLUSION: Use of multimodality intelligent workstations can improve the performance of radiologists in the task of differentiating malignant and benign lesions at mammography and sonography.

Adult↗

PubMed2006

Reality check: perceived versus actual performance of community mammographers.

OBJECTIVE: Federal regulations mandate that radiologists receive regular albeit limited feedback regarding their interpretive accuracy in mammography. We sought to determine whether radiologists who regularly receive more extensive feedback can report their actual performance in screening mammography accurately. SUBJECTS AND METHODS: Radiologists (n = 105) who routinely interpret screening mammograms in three states (Washington, Colorado, and New Hampshire) completed a mailed survey in 2001. Radiologists were asked to estimate how frequently they recommended additional diagnostic testing after screening mammography and the positive predictive value of their recommendations for biopsy (PPV2). We then used outcomes from 336,128 screening mammography examinations interpreted by the radiologists from 1998 to 2001 to ascertain their true rates of recommendations for diagnostic testing and PPV2. RESULTS: Radiologists' self-reported rate of recommending immediate additional imaging (11.1%) exceeded their actual rate (9.1%) (mean difference, 1.9%; 95% confidence interval [CI], 0.9-3.0%). The mean self-reported rate of recommending short-interval follow-up was 6.2%; the true rate was 1.8% (mean difference, 4.3%; 95% CI, 3.6-5.1%). Similarly, the mean self-reported and true rates of recommending immediate biopsy or surgical evaluation were 3.2% and 0.6%, respectively (mean difference, 2.6%; 95% CI, 1.8-3.4%). Conversely, radiologists' mean self-reported PPV2 (18.3%) was significantly less than their mean true PPV2 (27.6%) (mean difference, -9.3%; 95% CI, -12.4% to -6.2%). CONCLUSION: Despite regular performance feedback, community radiologists may overestimate their true rates of recommending further evaluation after screening mammography and underestimate their true positive predictive value.

Biopsy↗

PubMed2006

Digital and screen-film mammography: comparison of image acquisition and interpretation times.

OBJECTIVE: The objective of our study was to compare acquisition times and interpretation times of screening examinations using screen-film mammography and soft-copy digital mammography. MATERIALS AND METHODS: Technologist study acquisition time from examination initiation to release of the screenee was measured for both screen-film and digital mammography (100 cases each) in routine clinical practice. The total interpretation time for screening mammography was also measured for 183 hard-copy screen-film cases and 181 soft-copy digital cases interpreted by a total of seven breast imaging radiologists, four experienced breast imagers, and three breast imaging fellows. RESULTS: Screening mammography acquisition time averaged 21.6 minutes for screen-film and 14.1 minutes for digital, a highly significant 35% shorter time for digital than screen-film (p < 10(-17)). The average number of images per case acquired with digital mammography was higher than that for screen-film mammography (4.23 for screen-film, 4.50 for digital; p = 0.047). The total interpretation time averaged 1.4 minutes for screen-film mammography and 2.3 minutes for digital mammography, a highly significant 57% longer interpretation time for digital (p < 10(-11)). In addition, technical problems delaying interpretation were encountered in none of the 183 screen-film cases but occurred in nine (5%) of the 181 digital cases. CONCLUSION: Compared with screen-film mammography, the use of digital mammography for screening examinations significantly shortened acquisition time but significantly increased interpretation time. In addition, more technical problems were encountered that delayed the interpretation of digital cases.

Female↗

PubMed2005

American College of Radiology Imaging Network digital mammographic imaging screening trial: objectives and methodology.

This study was approved by the Institutional Review Board (IRB) of the American College of Radiology Imaging Network (ACRIN) and each participating site and by the IRB and the Cancer Therapy Evaluation Program at the National Cancer Institute. The study was monitored by an independent Data Safety and Monitoring Board, which received interim analyses of data to ensure that the study would be terminated early if indicated by trends in the outcomes. The ACRIN, which is funded by the National Cancer Institute, conducted the Digital Mammographic Imaging Screening Trial (DMIST) primarily to compare the diagnostic accuracy of digital and screen-film mammography in asymptomatic women presenting for screening for breast cancer. Over the 25.5 months of enrollment, a total of 49 528 women were included at the 33 participating sites, which used five different types of digital mammography equipment. All participants underwent both screen-film and digital mammography. The digital and screen-film mammograms of each subject were independently interpreted by two radiologists. If findings of either examination were interpreted as abnormal, subsequent work-up occurred according to the recommendations of the interpreting radiologist. Breast cancer status was determined at biopsy or follow-up mammography 11-15 months after study entry. In addition to the measurement of diagnostic accuracy by using the interpretations of mammograms at the study sites, DMIST included evaluations of the relative cost-effectiveness and quality-of-life effects of digital versus screen-film mammography. Six separate reader studies using the de-identified archived DMIST mammograms will also assess the diagnostic accuracy of each of the individual digital mammography machines versus screen-film mammography machines, the effect of breast density on diagnostic accuracy of digital and screen-film mammography, and the effect of different rates of breast cancer on the diagnostic accuracy in a reader study.

Breast Neoplasms↗

PubMed2005

Current realities of delivering mammography services in the community: do challenges with staffing and scheduling exist?

PURPOSE: To evaluate the current (2001-2002) capacity of community-based mammography facilities to deliver screening and diagnostic services in the United States. MATERIALS AND METHODS: Institutional review board approvals and patient consent were obtained. A mailed survey was sent to 53 eligible mammography facilities in three states (Washington, New Hampshire, and Colorado). Survey questions assessed equipment and staffing availability, as well as appointment waiting times for screening and diagnostic mammography services. Criterion-related content and construct validity were obtained first by means of a national advisory committee of academic, scientific, and clinical colleagues in mammography that reviewed literature on existing surveys and second by pilot testing a series of draft surveys among community mammography facilities not inclusive of the study facilities. The final survey results were independently double entered into a relational database with programmed data checks. The data were sent encrypted by means of file transfer protocol to a central analytical center at Group Health Cooperative. A two-sided P value with alpha = .05 was considered to show statistical significance in all analyses. RESULTS: Forty-five of 53 eligible mammography facilities (85%) returned the survey. Shortages of radiologists relative to the mammographic volume were found in 44% of mammography facilities overall, with shortages of radiologists higher in not-for-profit versus for-profit facilities (60% vs 28% reported). Shortages of Mammography Quality Standards Act-qualified technologists were reported by 20% of facilities, with 46% reporting some level of difficulty in maintaining qualified technologists. Waiting times for diagnostic mammography ranged from less than 1 week to 4 weeks, with 85% performed within 1 week. Waiting times for screening mammography ranged from less than 1 week to 8 weeks, with 59% performed between 1 week and 4 weeks. Waiting times for both diagnostic and screening services were two to three times higher in high-volume compared with low-volume facilities. CONCLUSION: Survey results show shortages of radiologists and certified mammography technologists.

Breast Neoplasms↗

PubMed2005

Does litigation influence medical practice? The influence of community radiologists' medical malpractice perceptions and experience on screening mammography.

PURPOSE: To assess the relationship between radiologists' perception of and experience with medical malpractice and their patient-recall rates in actual community-based clinical settings. MATERIALS AND METHODS: All study activities were approved by the institutional review boards of the involved institutions, and patient and radiologist informed consent was obtained where necessary. This study was performed in three regions of the United States (Washington, Colorado, and New Hampshire). Radiologists who routinely interpret mammograms completed a mailed survey that included questions on demographic data, practice environment, and medical malpractice. Survey responses were linked to interpretive performance for all screening mammography examinations performed between January 1, 1996, and December 31, 2001. The odds of recall were modeled by using logistic regression analysis based on generalized estimating equations that adjust for study region. RESULTS: Of 181 eligible radiologists, 139 (76.8%) returned the survey with full consent. The analysis included 124 radiologists who had interpreted a total of 557 143 screening mammograms. Approximately half (64 of 122 [52.4%]) of the radiologists reported a prior malpractice claim, with 18 (14.8%) reporting mammography-related claims. The majority (n = 51 [81.0%]) of the 63 radiologists who responded to a question regarding the degree of stress caused by a medical malpractice claim described the experience as very or extremely stressful. More than three of every four radiologists (ie, 94 [76.4%] of 123) expressed concern about the impact medical malpractice has on mammography practice, with over half (72 [58.5%] of 123) indicating that their concern moderately to greatly increased the number of their recommendations for breast biopsies. Radiologists' estimates of their future malpractice risk were substantially higher than the actual historical risk. Almost one of every three radiologists (43 of 122 [35.3%]) had considered withdrawing from mammogram interpretation because of malpractice concerns. No significant association was found between recall rates and radiologists' experiences or perceptions of medical malpractice. CONCLUSION: U.S. radiologists are extremely concerned about medical malpractice and report that this concern affects their recall rates and biopsy recommendations. However, medical malpractice experience and concerns were not associated with recall or false-positive rates. Heightened concern of almost all radiologists may be a key reason that recall rates are higher in the United States than in other countries, but this hypothesis requires further study.

Adult↗

PubMed2005

Community-based mammography practice: services, charges, and interpretation methods.

OBJECTIVE: The purpose of our study was to accurately describe facility characteristics among community-based screening and diagnostic mammography practices in the United States. MATERIALS AND METHODS: A survey was developed and applied to community-based facilities providing screening mammography in three geographically distinct locations in the states of Washington, Colorado, and New Hampshire. The facility survey was conducted between December 2001 and September 2002. Characteristics surveyed included facility type, services offered, charges for screening and diagnostic mammography, information systems, and interpretation methods, including the frequency of double interpretation. RESULTS: Among 45 responding facilities, services offered included screening mammography at all facilities, diagnostic mammography at 34 facilities (76%), breast sonography at 30 (67%), breast MRI at seven (16%), and nuclear medicine breast scanning at seven (16%). Most facilities surveyed were radiology practices in nonhospital settings. Eight facilities (18%) reported performing clinical breast examinations routinely along with screening mammography. Only five screening sites (11%) used computer-aided detection (CAD) and only two (5%) used digital mammography. Nearly two thirds of facilities interpreted screening mammography examinations on-site, whereas 91% of facilities interpreted diagnostic examinations on-site. Only three facilities (7%) interpreted screening examinations on line as they were performed. Approximately half of facilities reported using some type of double interpretation, although the methods of double interpretation and the fraction of cases double-interpreted varied widely across facilities. On average, approximately 15% of screening examinations and 10% of diagnostic examinations were reported as being double-interpreted. CONCLUSION: Comparison of this survey's results with those collected a decade earlier indicates dramatic changes in the practice of mammography, including a clear distinction between screening and diagnostic mammography, batch interpretation of screening mammograms, and improved quality assurance and medical audit tools. Diffusion of new technologies such as CAD and digital mammography was not widespread. The methods of double-interpretation and the fraction of cases double-interpreted varied widely across study sites.

Breast Neoplasms↗

PubMed2004

Accuracy of screening mammography interpretation by characteristics of radiologists.

BACKGROUND: Radiologists differ in their ability to interpret screening mammograms accurately. We investigated the relationship of radiologist characteristics to actual performance from 1996 to 2001. METHODS: Screening mammograms (n = 469,512) interpreted by 124 radiologists were linked to cancer outcome data. The radiologists completed a survey that included questions on demographics, malpractice concerns, years of experience interpreting mammograms, and the number of mammograms read annually. We used receiver operating characteristics (ROC) analysis to analyze variables associated with sensitivity, specificity, and the combination of the two, adjusting for patient variables that affect performance. All P values are two-sided. RESULTS: Within 1 year of the mammogram, 2402 breast cancers were identified. Relative to low annual interpretive volume (< or =1000 mammograms), greater interpretive volume was associated with higher sensitivity (P = .001; odds ratio [OR] for moderate volume [1001-2000] = 1.68, 95% CI = 1.18 to 2.39; OR for high volume [>2000] = 1.89, 95% CI = 1.36 to 2.63). Specificity decreased with volume (OR for 1001-2000 = 0.65, 95% CI = 0.52 to 0.83; OR for more than 2000 = 0.76, 95% CI = 0.60 to 0.96), compared with 1000 or less (P = .002). Greater number of years of experience interpreting mammograms was associated with lower sensitivity (P = .001), but higher specificity (P = .003). ROC analysis using the ordinal BI-RADS interpretation showed an association between accuracy and both previous mammographic history (P = .012) and breast density (P<.001). No association was observed between accuracy and years interpreting mammograms (P = .34) or mammography volume (P = .94), after adjusting for variables that affect the threshold for calling a mammogram positive. CONCLUSIONS: We found no evidence that greater volume or experience at interpreting mammograms is associated with better performance. However, they may affect sensitivity and specificity, possibly by determining the threshold for calling a mammogram positive. Increasing volume requirements is unlikely to improve overall mammography performance.

Adult↗

PubMed2004

The association between obesity and screening mammography accuracy.

BACKGROUND: Obesity is increasing among American women, especially as they age. The influence of obesity on the accuracy of screening mammography has not been studied extensively. METHODS: We analyzed 100 622 screening mammography examinations performed on members of a nonprofit health plan. The relationship between body mass index (weight in kilograms divided by the square of height in meters) and measures of screening accuracy was assessed. Body mass index was categorized as underweight or normal weight (<25), overweight (25-29), obesity class I (30-34), and obesity classes II to III (> or =35). RESULTS: Compared with underweight or normal weight women, overweight and obese women were more likely to be recalled for additional tests after adjusting for important covariates, including age and breast density (overweight odds ratio [OR], 1.17; 95% confidence interval [CI], 1.11-1.23); obesity class I OR, 1.27; 95% CI, 1.19-1.35; obesity classes II-III OR, 1.31; 95% CI, 1.22-1.41). As body mass index increased, women were more likely to have lower specificity (overweight OR, 0.86; 95% CI, 0.81-0.90; obesity class I OR, 0.79; 95% CI, 0.74-0.84; and obesity classes II-III OR, 0.77; 95% CI, 0.71-0.82). No statistically significant differences were noted in sensitivity. Adjusted receiver operating characteristic analysis showed statistically significant improvement in the area under the curve (AUC) for underweight or normal weight women (AUC = 0.941) vs overweight women (AUC = 0.916, P =.02) and underweight or normal weight women vs obesity classes II and III women (AUC = 0.904, P =.02). CONCLUSIONS: Obese women had more than a 20% increased risk of having false-positive mammography results compared with underweight and normal weight women, although sensitivity was unchanged. Achieving a normal weight may improve screening mammography performance.

Adult↗

PubMed2004

Digital mammography.

Despite its technical advantages, early clinical trials comparing digital mammography with film mammography for screening have been somewhat disappointing. Digital mammography,however, is in its infancy and can be expected to improve more rapidly than film mammography. Some areas of improvement being observed now include the development of new detector technologies; more powerful and better-designed interpretation workstations; and novel advanced applications, such as tomosynthesis and contrast-enhanced mammography, which are not possible with standard film mammography.

Contrast Media↗

PubMed2003

Physical inactivity and percent breast density among Hispanic women.

Results of epidemiologic studies suggest an inverse association between breast cancer risk and physical activity; this is one of the few modifiable breast cancer risk factors identified to date. However, only 2 previous studies assessed the association between physical activity and the extent of mammographically-detected fibroglandular breast density, a marker of breast cancer risk. Moreover, there has been no study of physical inactivity and percent breast density, nor a study of this relationship in Hispanic women, who are less physically active than non-Hispanic whites. In the Chicago Breast Health Project, we collected information on sociodemographic, reproductive, medical and lifestyle factors and percent breast density, assessed quantitatively using full-field digital mammography, from 294 Hispanic women. In our study, we examined the independent associations of hours per day of physical inactivity with percent breast density using multivariate linear regression analysis adjusting for age, education, body mass index, parity, menopausal status, use of hormone replacement therapy and smoking status. Overall, the mean percent breast density was low (i.e., 17.7%) and ranged from 1.9% to 54.6%. There was no difference in percent breast density for women who reported 1.5-3.0 hr of physical inactivity per day compared to women who reported 0-1 hr per day (beta = -0.08, p = 0.95), but percent density was marginally significantly higher for women who were reported at least 3.5 hr per day of physical inactivity (beta = 3.18, p = 0.056). Results were similar, albeit less statistically significant, in analyses of pre/perimenopausal and postmenopausal women separately. These results support the need for further research investigating the effect of physical activity on breast cancer risk.

Adult↗

PubMed2003

Optimization of technique factors for a silicon diode array full-field digital mammography system and comparison to screen-film mammography with matched average glandular dose.

Contrast-detail experiments were performed to optimize technique factors for the detection of low-contrast lesions using a silicon diode array full-field digital mammography (FFDM) system under the conditions of a matched average glandular dose (AGD) for different techniques. Optimization was performed for compressed breast thickness from 2 to 8 cm. FFDM results were compared to screen-film mammography (SFM) at each breast thickness. Four contrast-detail (CD) images were acquired on a SFM unit with optimal techniques at 2, 4, 6, and 8 cm breast thicknesses. The AGD for each breast thickness was calculated based on half-value layer (HVL) and entrance exposure measurements on the SFM unit. A computer algorithm was developed and used to determine FFDM beam current (mAs) that matched AGD between FFDM and SFM at each thickness, while varying target, filter, and peak kilovoltage (kVp) across the full range available for the FFDM unit. CD images were then acquired on FFDM for kVp values from 23-35 for a molybdenum-molybdenum (Mo-Mo), 23-40 for a molybdenum-rhodium (Mo-Rh), and 25-49 for a rhodium-rhodium (Rh-Rh) target-filter under the constraint of matching the AGD from screen-film for each breast thickness (2, 4, 6, and 8 cm). CD images were scored independently for SFM and each FFDM technique by six readers. CD scores were analyzed to assess trends as a function of target-filter and kVp and were compared to SFM at each breast thickness. For 2 cm thick breasts, optimal FFDM CD scores occurred at the lowest possible kVp setting for each target-filter, with significant decreases in FFDM CD scores as kVp was increased under the constraint of matched AGD. For 2 cm breasts, optimal FFDM CD scores were not significantly different from SFM CD scores. For 4-8 cm breasts, optimum FFDM CD scores were superior to SFM CD scores. For 4 cm breasts, FFDM CD scores decreased as kVp increased for each target-filter combination. For 6 cm breasts, CD scores decreased slightly as kVp increased for Mo-Mo, but did not change significantly as a function of kVp for either Mo-Rh or Rh-Rh. For 8 cm breasts, Rh/Rh FFDM CD scores were superior to other target-filter combinations and increased significantly as kVp increased. These results indicate that low-contrast lesion detection was optimized for FFDM by using a softer x-ray beam for thin breasts and a harder x-ray beam for thick breasts, when AGD was kept constant for a given breast thickness. Under this constraint, optimum low-contrast lesion detection with FFDM was superior to that for SFM for all but the thinnest breasts.

Equipment Failure Analysis↗

PubMed2003

Associations of breast cancer risk factors with breast density in Hispanic women.

Although there has been much research on the factors associated with breast density, most studies did not include Hispanic women or relied on semiquantitative methods of assessing density. Using data from the Chicago Breast Health Project, which targeted Hispanic women and assessed density quantitatively using full-field digital mammography, we assessed cross-sectional associations of breast cancer risk factors with percentage of breast density. Between November 2000 and June 2002, 296 Hispanic women recruited from three community health centers in Chicago, Illinois completed a health and lifestyle questionnaire, had their height and weight measured, and underwent screening mammography. The average percentage of total breast area occupied by fibroglandular tissue was computed from each mammographic view. Associations of breast cancer risk factors with percentage of breast density were assessed using multivariate linear regression analyses. Overall, the mean percentage of breast density was 17.6%. In multivariate analysis, older age was associated with lower density (P = 0.03), and density was lower among postmenopausal than premenopausal women (beta = 5.2%; P = 0.002). Body mass index was significantly inversely related to percentage of breast density (P < 0.00001). Women currently taking hormone replacement therapy had a higher percentage of breast density (beta = 3.3%; P = 0.03). In premenopausal women, cigarette smokers had a marginally higher percentage of density (beta = 6.23%; P = 0.06) compared with nonsmokers, but there was no relationship for postmenopausal women. Other breast cancer risk factors were not associated with density. In summary, breast density was strongly and inversely associated with age, body mass index, and menopausal status, and positively associated with hormone replacement therapy use and cigarette smoking. Additional research focusing on relationships of other, potentially modifiable, factors with the extent of breast density is warranted to better understand the interindividual variability in density among Hispanic women.

Adult↗

PubMed2002

Technical quality control practices in mammography screening programs in 22 countries.

OBJECTIVE: To assess current technical quality control (QC) practices within breast cancer screening or surveillance programs internationally. MATERIALS AND METHODS: The International Breast Cancer Screening Network (IBSN) conducted an extensive survey of quality assurance (QA) activities in developed countries known to have population-based breast cancer screening or surveillance programs in place. Twenty-three countries were sent questionnaires that included items about QA and QC requirements at screening sites, the minimum frequencies of QC test performance, and the personnel responsible for performing QC tests. RESULTS: All 23 countries in the IBSN completed general information on their QA practices. Twenty-two countries responded with complete details on their technical QC practices. The responses indicated a pattern of consistently high-quality control practices among population-based breast cancer screening and surveillance programs. Most programs performed the great majority of QC tests. Variations were observed in the performance frequencies of QC tests and in the personnel responsible for performing QC tests. CONCLUSION: QC practices among population-based breast cancer screening and surveillance programs are highly evolved, with the great majority of responding countries following prescribed QC protocols. Further research is needed on appropriate performance frequencies for mammography QC tests.

Accreditation↗

PubMed2002

Performance comparison of full-field digital mammography to screen-film mammography in clinical practice.

Results of acceptance testing 18 full-field digital mammography systems for clinical use and of conducting annual physics surveys of 38 screen-film mammography systems were compared in terms of exposure times, mean glandular breast doses, and image quality. These evaluations were made using the same test tools on all systems, with emphasis on assessing automatic exposure control performance and image quality on both digital and screen-film systems using clinical techniques. Survey results indicated that digital mammography systems performed similarly to screen-film systems in terms of exposure times and mean glandular doses for thin to intermediate breasts, but that digital mammography systems selected shorter exposure times and lower mean glandular doses for thicker breasts. For all breast thicknesses, digital mammography systems yielded mean contrast-detail scores higher than those for screen-film systems. For all breast thicknesses, the 18 digital mammography systems demonstrated less variance in terms of exposure times, mean glandular doses, and contrast-detail scores than did the 38 screen-film systems tested. These results indicate that the clinical use of digital mammography may generally improve image quality for equal or lower breast doses, while providing tighter control on exposures and image quality than screen-film mammography.

Biophysical Phenomena↗

PubMed2002

Clinical comparison of full-field digital mammography and screen-film mammography for detection of breast cancer.

OBJECTIVE: The purpose of this work is to compare full-field digital mammography and screen-film mammography for the detection of breast cancer in a screening population. SUBJECTS AND METHODS: Full-field digital mammography was performed in addition to screen-film mammography in 6736 examinations of women 40 years old and older presenting for screening mammography at either of two institutions. Two views of each breast were acquired with each technique. The digital and screen-film mammograms were each interpreted independently. In addition to a clinical assessment, each finding was assigned a probability of malignancy for use in receiver operating characteristic analysis. In cases in which the digital and screen-film interpretations differed, a side-by-side analysis was performed to determine the reasons for the discrepancy. With few exceptions, findings detected on either technique were evaluated with additional imaging and, if warranted, biopsy. RESULTS: Additional evaluation was recommended on at least one technique in 1467 cases. These additional evaluations led to 181 biopsies and the detection of 42 cancers. Nine cancers were detected only on digital mammography, 15 were detected only on screen-film mammography, and 18 were detected on both. The difference in cancer detection is not statistically significant (p > 0.1). Digital mammography resulted in fewer recalls than did screenfilm mammography (799 vs 1007, p < 0.001). The difference between the receiver operating characteristic curve area for digital (0.74) and screen-film (0.80) mammography was not significant (p > 0.1). Reasons for discrepant interpretations of cancer were approximately equally distributed among those relating to lesion conspicuity, lesion appearance, and interpretation. CONCLUSION: No significant difference in cancer detection was observed between digital mammography and screen-film mammography. Digital mammography resulted in fewer recalls than did screen-film mammography.

Adult↗