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ABSTRACT: The purpose of this article is to compare the ability of digital breast tomosynthesis and full field digital mammography (FFDM) to detect and characterize calcifications.
One hundred paired examinations were performed utilizing FFDM and digital breast tomosynthesis. Twenty biopsy-proven cancers, 40 biopsy-proven benign calcifications, and 40 randomly selected negative screening studies were retrospectively reviewed by five radiologists in a crossed multireader multimodal observer performance study. Data collected included the presence of calcifications and forced BI-RADS scores. Receiver operator curve analysis using BI-RADS was performed.
Overall calcification detection sensitivity was higher for FFDM (84% [95% CI, 79-88%]) than for digital breast tomosynthesis (75% [95% CI, 70-80%]). [corrected] In the cancer cohort, 75 (76%) of 99 interpretations identified calcification in both modes. Of those, a BI-RADS score less than or equal to 2 was rendered in three (4%) and nine (12%) cases with FFDM and digital breast tomosynthesis, respectively. In the benign cohort, 123 (62%) of 200 interpretations identified calcifications in both modes. Of those, a BI-RADS score greater than or equal to 3 was assigned in 105 (85%) and 93 (76%) cases with FFDM and digital breast tomosynthesis, respectively. There was no significant difference in the nonparametric computed area under the receiver operating characteristic curves (AUC) using the BI-RADS scores (FFDM, AUC = 0.76 and SD = 0.03; digital breast tomosynthesis, AUC = 0.72 and SD = 0.04 [p = 0.1277]).
In this small data set, FFDM appears to be slightly more sensitive than digital breast tomosynthesis for the detection of calcification. However, diagnostic performance as measured by area under the curve using BI-RADS was not significantly different. With improvements in processing algorithms and display, digital breast tomosynthesis could potentially be improved for this purpose.
American Journal of Roentgenology 02/2011; 196(2):320-4. · 2.78 Impact Factor
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ABSTRACT: To compare pelvic anatomy, using magnetic resonance imaging, between postpartum women with or without pelvic floor disorders. We measured postpartum bony and soft tissue pelvic dimensions in 246 primiparas, 6-12-months postpartum. Anatomy was compared between women with and without urinary or fecal incontinence, or pelvic organ prolapse; P < 0.01 was considered statistically significant. A deeper sacral hollow was significantly associated with fecal incontinence (P = 0.005). Urinary incontinence was marginally associated with a wider intertuberous diameter (P = 0.017) and pelvic arch (P = 0.017). There were no significant differences in pelvimetry measures between women with and without prolapse (e.g., vaginal or cervical descent to or beyond the hymen). We did not detect meaningful differences in soft tissue dimensions for women with and without these pelvic floor disorders. Dimensions of the bony pelvis do not differ substantially between primiparous women with and without postpartum urinary incontinence, fecal incontinence and prolapse.
International Urogynecology Journal 10/2008; 20(2):133-9. · 1.83 Impact Factor
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ABSTRACT: The objective of the study was to identify risk factors for internal anal sphincter (IAS) gaps on postpartum endoanal ultrasound in women with obstetric anal sphincter tear.
This prospective study included 106 women from the Childbirth and Pelvic Symptoms Imaging Supplementary Study who had third- or fourth-degree perineal laceration at delivery and endoanal ultrasound 6-12 months postpartum. Data were analyzed using Fisher's exact and t tests and logistic regression.
Mean (+/- SD) age was 27.7 (+/- 6.2) years. Seventy-nine women (76%) were white and 22 (21%) black. Thirty-seven (35%) had sonographic IAS gaps. Risk factors for gaps included fourth- vs third-degree perineal laceration (odds ratio [OR] 15.4, 95% confidence interval [CI] 4.8, 50) and episiotomy (OR 3.3, 95% CI 1.2, 9.1). Black race (OR 0.23, 95% CI 0.05, 0.96) was protective.
In women with obstetric anal sphincter repairs, fourth-degree tears and episiotomy are associated with more frequent sonographic IAS gaps.
American journal of obstetrics and gynecology 10/2007; 197(3):310.e1-5. · 3.28 Impact Factor
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Holly E Richter,
Julia R Fielding,
Catherine S Bradley,
Victoria L Handa,
Paul Fine,
Mary Pat FitzGerald,
Anthony Visco,
Arnold Wald, Christiane Hakim,
J T Wei,
Anne M Weber
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ABSTRACT: To estimate whether endoanal ultrasound findings are more prevalent in primiparous women with a history of anal sphincter tear than in women without this history and whether the findings are associated with fecal incontinence symptoms.
A total of 251 primiparous women at seven clinical sites underwent standardized ultrasound assessment of the internal and external anal sphincter 6-12 months after delivery. Participants were women in the three cohorts of the Childbirth and Pelvic Symptoms Study: 1) women with clinically evident third- or fourth-degree tear at vaginal delivery (n=106); 2) no tear at vaginal delivery (n=106); and 3) cesarean delivery without labor (n=39). Women completed the Fecal Incontinence Severity Index to assess fecal incontinence symptoms.
Thirty-five percent of the sphincter tear group exhibited internal sphincter gaps compared with 3% of vaginal controls (odds ratio [OR] 18.4, 95% confidence interval [CI] 5.5-62.1) and 10% of cesarean controls. External sphincter gaps were identified in 51% of the tear group compared with 31% of vaginal controls (OR 2.3, 95% CI 1.3-4.0) and 28% of cesarean controls. In the tear group, fecal incontinence severity was greater in those with internal sphincter gaps compared with those with no internal sphincter gaps (Fecal Incontinence Severity Index score 6.6+/-8.3 compared with 3.3+/-6.1, P=.02), as well as in those with external sphincter gaps (6.1+/-8.4 compared with 2.7+/-5.0, P=.01), and greatest in those with both internal and external sphincter gaps compared with at least one gap not present (7.2+/-8.1 compared with 3.4+/-6.4, P=.003).
Anal sphincter gaps detected by ultrasonography are prevalent in postpartum primiparous women with a history of sphincter tear and are associated with fecal incontinence severity.
II-2.
Obstetrics and Gynecology 01/2007; 108(6):1394-401. · 4.73 Impact Factor
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ABSTRACT: We compared performance and visual search parameters of radiologists detecting masses on mammograms by using both a head-mounted (HDMT) and a remote (REM) eye tracker.
Five experienced radiologists read twice a case set of 20 one-view (medial-lateral oblique) mammograms, of which 12 contained a malignant mass and eight were lesion-free. For each observer, one trial used an HDMT eye-tracking system and the other used an REM system. Trials were separated on average by 2 months. Time to hit the location of the mass, dwell, and number of fixations in the location of the mass were measured. The same parameters were measured on a per-trial basis to determine whether there were memory effects from the previous trial.
Dwell times in the location of true-positive, false-positive, and false-negative results were significantly shorter (P < .05) using the HDMT (median, 0.395 seconds) than REM (median, 0.482 seconds) systems, but the number of fixations in the location of the response was smaller using the REM system (median, 4.33 versus 5.0 for the HDMT). The observed differences did not seem to be caused by a memory effect. In addition, the relative lack of head mobility using the REM system caused observers to report neck strain.
Overall, radiologists' visual search behavior was very similar using both types of eye-tracking device. However, because the REM system did not contain a magnetic head tracker, radiologists were allowed very limited head movements when using it, which made them uncomfortable during the experiment.
Academic Radiology 03/2006; 13(2):203-9. · 1.69 Impact Factor
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ABSTRACT: The goal of mammography screening is to detect breast cancer at early stages, but because of the complexity of the breast parenchyma and the variability of signs of the disease, many cancers go unreported when initially visible on the mammogram. We compared the visual search strategy used by experienced mammographers in a case set where they examined both the mammogram in which a malignant mass was discovered at screening mammography and the most recent prior mammogram.
Four experienced mammographers participated in this experiment. They read a case set of 20 two-view mammograms, of which 15 contained a malignant mass and 5 were lesion-free, in two trials. For each of the cancer cases, two versions were shown to the observers: the one in which the cancer was reported in the clinical practice, called the "current" mammograms, and the most recent prior. Each trial had a balanced mix of current and prior mammograms. In addition, the same set of lesion-free cases was shown to the observers in both trials. The eye movements of the observers were tracked, and visual search parameters such as time to hit the location of the malignant mass, dwell, and mean pupil size in the location of the cancer were collected. Statistical analyses were used to determine whether there were differences between the current and prior mammograms.
A total of 66% of the malignant masses in the current mammograms and 57% in the priors attracted some amount of visual attention. From these, 71% yielded a report on the current mammograms, but only 40% on the priors. In the cases where the observer saw the malignant mass, they did so within 2 seconds of image display, regardless of whether the mammogram was current or prior.
Most unreported malignant masses attracted some amount of visual attention, but it was in the processing of the information extracted in the location of the lesion that most errors occurred. In our experiment, approximately 70% of the total time used by the observers for visual scan of the cases was spent gathering information to corroborate the hypothesis already formed by the radiologist.
Academic Radiology 08/2005; 12(7):830-40. · 1.69 Impact Factor
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ABSTRACT: Computer-aided mammography is rapidly gaining clinical acceptance, but few data demonstrate its actual benefit in the clinical environment. We assessed changes in mammography recall and cancer detection rates after the introduction of a computer-aided detection system into a clinical radiology practice in an academic setting.
We used verified practice- and outcome-related databases to compute recall rates and cancer detection rates for 24 Mammography Quality Standards Act-certified academic radiologists in our practice who interpreted 115,571 screening mammograms with (n = 59,139) or without (n = 56,432) the use of a computer-aided detection system. All statistical tests were two-sided.
For the entire group of 24 radiologists, recall rates were similar for mammograms interpreted without and with computer-aided detection (11.39% versus 11.40%; percent difference = 0.09, 95% confidence interval [CI] = -11 to 11; P =.96) as were the breast cancer detection rates for mammograms interpreted without and with computer-aided detection (3.49% versus 3.55% per 1000 screening examinations; percent difference = 1.7, 95% CI = -11 to 19; P =.68). For the seven high-volume radiologists (i.e., those who interpreted more than 8000 screening mammograms each over a 3-year period), the recall rates were similar for mammograms interpreted without and with computer-aided detection (11.62% versus 11.05%; percent difference = -4.9, 95% CI = -21 to 4; P =.16), as were the breast cancer detection rates for mammograms interpreted without and with computer-aided detection (3.61% versus 3.49% per 1000 screening examinations; percent difference = -3.2, 95% CI = -15 to 9; P =.54).
The introduction of computer-aided detection into this practice was not associated with statistically significant changes in recall and breast cancer detection rates, both for the entire group of radiologists and for the subset of radiologists who interpreted high volumes of mammograms.
CancerSpectrum Knowledge Environment 03/2004; 96(3):185-90. · 14.07 Impact Factor
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ABSTRACT: The authors assessed and compared the performance of a computer-aided detection (CAD) scheme for the detection of masses and microcalcification clusters on a set of images collected from two consecutive ("current" and "prior") mammographic examinations.
A previously developed CAD scheme was used to assess two consecutive screening mammograms from 200 cases in which the current mammogram showed a mass or cluster of microcalcifications that resulted in breast biopsy. The latest prior examinations had been initially interpreted as negative or definitely benign findings (Breast Imaging Reporting and Data System rating, 1 or 2). The study involved images of 400 examinations acquired in 200 patients. Radiologists identified 172 masses and 128 clusters of microcalcifications on the current images. The performance of the CAD scheme was analyzed and compared for the current and latest prior images.
There were significant differences (P < .01) between current and prior images in many feature values. The performance of the CAD scheme was significantly lower for prior than for current images (P < .01). At 0.5 and 0.2 false-positive mass and cluster cues per image, the scheme detected 78 malignant masses (78%) and 63 malignant clusters (80%) on current images. Only 42% of malignant cases were detected on prior images, including 40 masses (40%) and 36 microcalcification clusters (46%).
CAD schemes can detect a substantial fraction of masses and microcalcification clusters depicted on prior images. To improve performance with prior images, the scheme may have to be adaptively reoptimized with increasingly more subtle abnormalities.
Academic Radiology 11/2002; 9(11):1245-50. · 1.69 Impact Factor
