Reading Of Mammograms Research Articles

Unobtrusively tracking eye gaze direction and pupil diameter of mammographers

The visual process that radiologists use for diagnosis is incompletely understood. This study developed techniques to unobtrusively track direction and pupil diameter of radiologists reading a wide variety of films. We evaluated the eye gaze patterns of mammographic experts to gain knowledge that might improve the rate of early detection of breast cancer. A video camera with a near-infrared light filter is pointed at the mammographic expert who is reading mammograms. The video images are analyzed in real time on a personal computer to detect eye gaze direction and pupil diameter. Two separate trials were used: 1) to demonstrate the system's speed and ability to work with mammograms (a brief test with one mammographer was used) and 2) four mammographic experts evaluated 14 mammograms. In the first trial, the system successfully tracked the eye gaze of a mammographer who quickly recognized the patient case, with the pupil diameter briefly increasing 40%, and then the gaze direction dwelling in an area of microcalcifications. In the second trial, 66% of the false-positive results for films with masses were associated with long eye gaze dwells, whereas 33% of the prolonged dwells for films with microcalcifications were associated with true-positive diagnoses. This near-infrared light system successfully tracked the eye gaze direction and pupil diameter of mammographic experts evaluating films. The association of long eye gaze dwells with diagnostic accuracy varied with the type of object being viewed. In films with masses, false-positive diagnoses were associated with long dwells. In films with microcalcifications, true-positive diagnoses were associated with long dwells.

The efficacy of double reading mammograms in breast screening

The effect of double reporting the screening mammograms of 31,146 women attending as part of the UK National Health Service Breast Screening Programme was analysed. Ninety per cent had their mammograms read by two of three experienced radiologists. Overall 1846 (5.9%) women were recalled for further assessment. Two hundred and sixty-one patients (0.8%) underwent surgical intervention resulting in the detection of 191 cancers (6.1/1000 women screened). The benign-to-malignant ratio was 1:3.6 (PPV 73.2%). Of the invasive cancers detected 72% had no histological evidence of axillary lymph node metastases. Twenty-one of the 191 cancers detected (10.4%) were missed by one of the two reporters. Six of these were invasive cancers < or = 1 cm in diameter. Comparison of those lesions detected by both readers to those detected by only one, showed readers were more likely to detect those lesions appearing as an opacity (65% vs 38%), but less likely to detect significant microcalcification (15% vs 33%). The difference between the two groups when taken as a whole, however, failed to reach statistical significance (chi 2 = 6.76, d.f. = 3, P = 0.08). In summary, double reporting resulted in an increase in sensitivity of 10%. However, there was a decrease in specificity of 1.8% with 569 women being recalled unnecessarily for assessment and biopsy of 13 benign lesions. The estimated resultant additional financial cost was 13773 pounds.

Psychological consequences of screening mammography.

To examine the psychological consequences at a number of stages in the screening process for women attending a screening mammography programme. A pilot mammographic screening programme in Melbourne, Australia. The psychological consequences questionnaire (PCQ; a reliable and valid measure of the psychological consequences of screening mammography) was used to measure the emotional, social, and physical functioning of women in a mammographic screening programme and a control community sample. A screening group (in whom no abnormality was detected at initial screen; n = 142) had four measurements: at screening clinic; before results were received; one week after all-clear results were received; and eight months after initial visit. The recall group (who were recalled for further investigation which showed the detected abnormality to be benign; n = 58) had measurements at the same points as the screening group and an additional measurement while waiting at the recall assessment clinic. A randomly selected community control group (n = 52) had measurements one week, two weeks, three weeks, and eight months after consenting to participate. Emotional, social, and physical functioning of women in the screening group did not change over time and at no point differed significantly from that of community controls. The profiles of emotional and physical dysfunction of women in the recall group differed significantly from those of the screening and control groups. The level of emotional and physical dysfunction in the recall group was highest while waiting at recall assessment clinic, and scores were still significantly higher than scores obtained at comparable times from screening and control groups one week after obtaining notification that there was no sign of cancer (emotional P < 0.001; physical P < 0.05). This difference had disappeared eight months after the screening visit, when the level of emotional and physical functioning was similar to that of the screening and control groups. Social dysfunction scores did not change significantly over time and were similar for all three groups. Given that up to 10% of women are recalled for further investigations on first round screening, significant numbers of women may have psychological consequences. This speaks for the necessity for accurate reading of mammograms to minimise the false positive recall rate, and for counselling services to be available at recall assessment centres.

Mammography in Singapore.

Summary An analysis is made of 223 cases of mammography seen in the Outram Road General Hospital, Singapore, from October 1967 to May 1971. All cases had histological confirmation. There were 90 (40‐36%) cases of carcinoma. The mammographic diagnosis, when combined with clinical examination, was 93% correct. The diagnosis based on the reading of mammograms alone was 71 % correct. Calcification in carcinoma occurred in 27% of cases, but only 11 % showed fine sand‐like calcifications. The skin was thickened in 22% of cases. There were 56 cases (25‐11%) of fibroadenoma. The accuracy of mammography taken in conjunction with clinical findings was 32%; mammography alone gave a 30% accuracy. Calcification was seen in 11 % of cases. Forty cases (17–94%) of mammary dysplasia were seen. Mammography in association with clinical examination was 32% correct; mammography alone was 30% correct. Thus the accuracy rates for both fibroadenoma and for mammary dysplasia were much lower than for carcinoma. An assortment of other non‐malignant conditions numbered 37 cases (16–59%). The accuracy rate was the lowest for this group, coming to 16% when mammography was combined with clinical examination, and only 8% when mammograms alone were read. Approximately 20% of all non‐malignant conditions were incorrectly interpreted as carcinoma from mammograms. Mammography is found to be a useful procedure in the detection of cancer of the breast in Asian women. Unpublished data from the Singapore Cancer Registry shows that cancer of the breast is the commonest malignant tumour in the female. It is therefore anticipated that mammography will be increasingly employed in the developing countries of South‐East Asia in the years to come.

New techniques in mass screening for breast cancer.

A substantial short-term reduction in mortality from breast cancer h as been obtained in a study group of 31000 women following the mammography project of the Health Insurance Plan of Greater New York. 1/3 of cancers found would have been undetected by clinical examination. The study included an initial and 3 subsequent annual examinations. Cancers were detected after 1 year of previous negative findings. The mammography was carried out with special portable X-ray e quipment using 70 mm film. The X-ray technicians have developed skill as prescreeners in reading mammograms. Paramedical personnel have been trained to do clinical examinations of the breasts while others have been trained in thermography. The entire examination can be completed in 10 minutes. It consists of an interview a clinical examination mammography and thermography. These methods are considered complementary. X-ray is omitted in patients under age 35. 6604 initial examinations were made the 1st year. 494 biopsies were performed. 55 cancers (8.3 per 1000) were found. Of these 19 were found on clinical examination 10 by mammography alone and 26 by 2 or more methods. This high detection rate was thought to be due to self-selection factors by the self-referred women. Follow-up care was provided by hospitals in the city. Papanicolaou cervical screening and chest X-rays were added at 1 center. A mobile van has been developed for use in many communities. To develop motivation and acceptance by women of each area a corps of health aids canvassed the community on a person-to-person basis.