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E D Pisano

Publications and source records attributed to E D Pisano.

52 records · Page 3Linked to original sources
PubMed1994

A method for determination of optimal image enhancement for the detection of mammographic abnormalities.

We present a paradigm for empirical evaluation of digital image enhancement algorithms for mammography that uses psychophysical methods for implementation and analysis of a clinically relevant detection task. In the experiment, the observer is asked to detect and assign to a quadrant, or indicate the absence of, a simulated mammographic structure characteristic of cancer embedded in a background image of normal breast tissue. Responses are indicated interactively on a computer workstation. The parameter values for the enhancement applied to the composite image may be varied on each trial, and structure detection performance is estimated for each enhancement condition. Preliminary investigations have provided insight into an appropriate viewing duration, and furthermore, suggest that nonradiologists may be used under this methodology for the tasks investigated thus far, for predicting parameter values for clinical investigation. We are presently using this method in evaluating several contrast enhancement algorithms of possible benefit in mammography. These methods enable an objective, clinically relevant evaluation, for the purpose of optimal parameter determination or performance assessment, of digital image-processing methods potentially used in mammography.

Algorithms↗
PubMed1994

Eye movement during computed tomography interpretation: eyetracker results and image display-time implications.

Stacked displays hold the potential for accurate interpretation of multiple computed tomography (CT) studies on a low-cost workstation. But can such a display scroll as quickly as radiologists can move their eyes to the next image on a film? To address this question, eye-movement duration during CT chest interpretation was recorded using an electronic eye tracker. Adjacent eye movements (+/- 1 image in sequence) averaged 0.54 seconds. Time motion analysis indicates that a CT workstation using a stacked approach with a 0.2-second image display time and a simple interaction can display the next image in less than 0.4 seconds, so a stacked approach should allow a low-cost workstation to facilitate acceptable interpretation of multiple CT or magnetic resonance studies. However, nonadjacent eye movements is likely to take longer and radiologist behavior may be effected.

Data Display↗
PubMed1994

Breast imaging fellowship programs. A survey of the fellows of the Society of Breast Imaging.

RATIONALE AND OBJECTIVES: Breast imaging, a subspecialty of diagnostic radiology, is becoming more important with the increased performance of screening mammography. Fellowships in breast imaging are being offered at many institutions. Information regarding the contents and structure of such fellowships is important for potential trainees and departments considering offering such programs. METHODS: All 79 fellows of the Society of Breast Imaging (SBI) were surveyed by mail. Those with breast imaging fellowships were asked questions about their program. All were asked their opinions about the appropriate features of a breast imaging fellowship. RESULTS: Forty-six (58%) surveys were returned. Nineteen respondents described breast imaging fellowships offered at 18 different institutions. CONCLUSIONS: This information may be useful as radiologists consider establishing fellowship standards within this subspecialty.

Breast Neoplasms↗
PubMed1993

Real-time radiologist review of remote ultrasound using low-cost video and voice.

RATIONALE AND OBJECTIVES: A radiologist practicing remote ultrasound occasionally needs to review a case in real time before releasing the patient. The authors conducted a pilot study to evaluate one solution in which the radiologist views real-time images on a video monitor while conversing with the technologist via a headset telephone. METHODS: Two experienced ultrasonographers and five technologies participated in a 5-week pilot study in adjacent rooms. RESULTS: Subjective assessment indicated that the system could function well enough for use at a remote site. CONCLUSIONS: Although this technology appears effective, an ongoing training environment is recommended.

Attitude of Health Personnel↗
PubMed1993

A formal curriculum in breast imaging for radiology residents.

RATIONAL AND OBJECTIVES: Training in breast imaging is highly variable among radiology programs. The authors have developed a standardized breast imaging curriculum for radiology residents. METHODS: This curriculum has been implemented within the residency program at the University of North Carolina at Chapel Hill. It includes nine standardized components: 1) the clinical activities of the service; 2) the study of breast imaging teaching file films and contribution of new cases; 3) selected readings; 4) formal discussion with faculty on the readings; 5) review of this material using an interactive computer program; 6) formal conferences; 7) technical and quality control activities; 8) research activities; and 9) an evaluation. The participating residents have been surveyed regarding their opinions of their educational experience. RESULTS AND CONCLUSION: The standardized curriculum has been well received by the participating residents. Conclusions about the educational efficacy of such a curriculum cannot be made until more residents have used it.

Computer-Assisted Instruction↗
PubMed1993

Effects of delayed processing on mammographic phantom object detection.

OBJECTIVES: Delayed processing of films is a common occurrence in mobile mammography screening programs. The effects of such delayed processing on radiologists' detection of phantom test objects are investigated. METHODS: Twelve screen-film combinations were exposed using a phantom and developed after delays of 0, 1, 2, 3, 5, and 7 days. Films were scored by three board-certified radiologists specializing in mammography, based on visibility of calcifications, masses, fibrils, and line pairs. RESULTS: Variance analyses of mean scores indicate that, across screen-film combinations, there are no statistically significant decreases in object detection associated with delayed processing. The analyses do indicate, however, a statistically significant difference in scores unrelated to delay, attributable to the screen-film combination used. CONCLUSIONS: Delayed processing of mammography film does not lead to a decrease in the visibility of phantom test objects, despite large decreases in overall image optical density.

Analysis of Variance↗
PubMed1992

The politics of mammography.

Mammography has had a major impact on the earlier detection, treatment options, and management decisions and survival and mortality rates of breast cancer. Consequences include overwhelming demand for mammography; problems with optimum response by radiology; limited availability of the examination, especially to the socioeconomically disadvantaged; self-referral for mammography by unqualified physicians for less than altruistic reasons; and unrealistic expectations of mammography by women, physicians, and lawyers. Responses to the overwhelming demand for high-quality mammography include ACR postgraduate and continuing education courses and its mammography accreditation program; a more comprehensive examination on mammography for certification by the ABR; and increasing state and federal government interest and legislation for reimbursement, quality assurance, and delivery of mammography. The precedents this sets for radiology if not all of medicine suggests that collaboration of the private and public sectors offers the greatest promise of an appropriate response, namely reproducible optimum mammography accurately interpreted with the lowest possible radiation dose for all eligible women in the United States.

Breast Neoplasms↗
PubMed1991

Implementation of breast cancer screening.

Mammography, breast physical examination, and breast self-examination are recommended for breast cancer screening. Although in randomized trials of screening, mammography demonstrated a reduction in breast cancer mortality for women over 50, such data are not available for breast physical or self-examination. The Canadian National Breast Screening Study should provide data regarding the efficacy of breast physical examination alone. The World Health Organization has established trials to evaluate self-examination in the USSR and Germany. There is still controversy regarding routine mammographic screening and the optimal screening interval for women under age 50. The costs of mammographic screening remain a concern, but these costs can be lessened considerably through efficiency of mammographic services and a reduction in the number of false-positive interpretations that prompt biopsy. Primary care physicians can help to reduce breast cancer mortality by referring their patients for screening mammography and by performing breast physical examinations.

Breast↗
PubMed1990

Issues in mammography.

The goals of screening mammography are reproducibly optimum images, accurately interpreted, at the lowest possible cost. This can reduce the mortality from breast cancer. Despite this, screening mammography has not been widely used because of the controversy over the age at onset and interval of screening, charge for the examination, misinformed primary care physicians, uninformed women, and other factors. The American College of Radiology's educational efforts and mammography accreditation program are overcoming some of these obstacles.

Adult↗
PubMedDate not supplied

What every surgical oncologist should know about digital mammography.

This article reviews the available information on digital mammography for surgeons who care for patients with breast cancer. The limitations of the current film-based technology and why digital mammography promises to improve breast cancer detection and breast lesion diagnosis are described. The basics of digital imaging technology are reviewed, including a description of image contrast and spatial resolution and its variance from currently available clinical digital mammography systems. The results of clinical trials completed to date are reported. An upcoming large screening trial for digital mammography, sponsored by the National Cancer Institute, is described. Future technological developments, including improvements in softcopy display, image processing, computer-aided detection and diagnosis (CADD), tomosynthesis, and digital subtraction mammography (DSM), are briefly discussed.

Breast Neoplasms↗
PubMedDate not supplied

Observer variability in the pulmonary examination.

Observer variability in the pulmonary examination was assessed by having four blindfolded observers (two medical students and two pulmonary physicians) twice examine 31 patients with abnormal pulmonary findings. Examiners were consistent in the repetitive detection of pulmonary abnormalities in 74-89% of the examinations; conversely, 11-26% of the time they disagreed with themselves. Although pulmonary specialists recorded fewer (55% of observations) abnormal findings than did medical students (74%), they were significantly (p = 0.008) less self-consistent than were the students. There was no clear trend in agreement between examiners (kappa = 0.20-0.49). Each examiner's findings were compared with those of physicians specially trained in pulmonary examination. Dichotomous variables (wheezes, crackles, rubs) were more reliably detected (kappa = 0.30-0.70) than graded variables (tympany, dullness, breath sound intensity), where kappa = 0.16-0.43. The authors suggest that dichotomous variables deserve greatest clinical reliance; that time in training, alone, does not improve clinical performance; and that there is a disconcertingly large amount of inter- and intraobserver disagreement in this fundamental clinical task.

Humans↗
PubMedDate not supplied

Ultrasound and MR findings in acute Budd-Chiari syndrome with histopathologic correlation.

This report describes the sonographic and MR appearances of acute Budd-Chiari syndrome (BCS) in a 30-year-old woman. Current imaging techniques including duplex Doppler sonography and dynamic gadolinium-enhanced MRI were employed, and direct histopathologic correlation was made. Duplex Doppler sonography revealed a heterogeneous enlarged liver, no flow in the left and middle hepatic veins, and only trace abnormal flow in the distal-most right hepatic vein. Dynamic serial gadolinium-enhanced, spoiled gradient echo imaging demonstrated early homogeneous enhancement of an enlarged caudate lobe, as well as heterogeneously decreased enhancement of the remainder of the hepatic parenchyma. This differential enhancement pattern persisted on delayed imaging. Patent hepatic veins were not demonstrated on any sequence. Associated findings included hepatomegaly, ascites, and patent portal vasculature. These imaging findings were interpreted as consistent with acute BCS. Within 10 days, the patient underwent orthotopic liver transplantation. Histopathology demonstrated hepatic necrosis and hepatic venous thrombosis consistent with acute BCS.

Acute Disease↗
PubMedDate not supplied

Paget disease of the breast: a pictorial essay.

Paget disease of the breast accounts for approximately 2%-3% of breast cancers. It is characterized by infiltration of the nipple epidermis by adenocarcinoma cells, which cause an eczematous eruption on the nipple and areola. The clinical features are highly suggestive of the disease; awareness of these on the part of the clinician should lead to more prompt diagnosis and earlier initiation of appropriate treatment. Mammograms, although not always positive, should be obtained in all cases suggestive of Paget disease to search for the underlying tumor and direct further treatment. Findings that may be seen at mammography include skin thickening, nipple retraction, subareolar or more diffuse malignant microcalcifications, and a discrete mass or masses. However, a negative mammogram should not alter the course of treatment. Conversely, identification of subareolar mammographic findings should alert the clinician to search for physical signs in the nipple and areolar region suggestive of Paget disease.

Breast Neoplasms↗
PubMedDate not supplied

Image processing algorithms for digital mammography: a pictorial essay.

Digital mammography systems allow manipulation of fine differences in image contrast by means of image processing algorithms. Different display algorithms have advantages and disadvantages for the specific tasks required in breast imaging-diagnosis and screening. Manual intensity windowing can produce digital mammograms very similar to standard screen-film mammograms but is limited by its operator dependence. Histogram-based intensity windowing improves the conspicuity of the lesion edge, but there is loss of detail outside the dense parts of the image. Mixture-model intensity windowing enhances the visibility of lesion borders against the fatty background, but the mixed parenchymal densities abutting the lesion may be lost. Contrast-limited adaptive histogram equalization can also provide subtle edge information but might degrade performance in the screening setting by enhancing the visibility of nuisance information. Unsharp masking enhances the sharpness of the borders of mass lesions, but this algorithm may make even an indistinct mass appear more circumscribed. Peripheral equalization displays lesion details well and preserves the peripheral information in the surrounding breast, but there may be flattening of image contrast in the nonperipheral portions of the image. Trex processing allows visualization of both lesion detail and breast edge information but reduces image contrast.

Algorithms↗