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B Threatt

Publications and source records attributed to B Threatt.

16 recordsLinked to original sources
PubMed1985

Incidence of mammary intra-arterial calcification: an age-matched control study.

Mammary intra-arterial calcification (MIAC) was seen on the mammograms of 13 of 150 (8.7%) known diabetic patients and 21 of 300 (7.0%) age-matched control patients. Statistical analysis verified no significant difference between the rate of occurrence of MIAC in the diabetic group of patients and the control group. Therefore, contrary to previous reported studies, our study does not support the conclusion of an increased frequency of MIAC in diabetic patients. MIAC is a manifestation of peripheral vascular disease resulting from a variety of causes, one of which may be diabetes.

Adult↗
PubMed1984

Characteristics of breast cancer in an incident cancer population.

The effectiveness of film mammography is a source of concern to radiologists because neither the ribs nor retromammary space is included on the films in good quality examinations. One hundred seven incident cancers were detected in 10,034 self-referred women followed at the University of Michigan Breast Cancer Detection Demonstration Project (UM-BCDDP) for 5 years. These cancers were analyzed for location on the film, method of detection, size, histology, and the number of films required for detection. Mammography alone detected 52 (49%) of the cancers, whereas physical examination alone detected 15 (14%). The other 40 cancers were detectable on both examinations. All of the 92 cancers detected by mammography were visible in both the mediolateral and the craniocaudal views. Only 2.2% of these cancers were within 1 cm of the posterior edge of the film in the mediolateral view; 18.7% were within 1 cm of the posterior edge in the craniocaudal view. These incident cancers were smaller, and fewer were located within the posterior 1 cm of the breast than in a similar study using the UM-BCDDP prevalent cancer population. Mammography consistently detected cancer in the breast, regardless of tumor size, histologic type, or location within the breast.

Adult↗
PubMed1984

Mammographic intra-arterial calcifications.

There is controversy about the significance of intra-arterial mammographic calcification ( MIAC ). Radiographic MIAC was found in mammograms of 78 of a total of 914 patients. The patients were analyzed for risk factors associated with arteriosclerosis, i.e., hypertension, diabetes, and age. Of the patients with MIAC , 83% were 60 years or older; 21% had no clinical history of diabetes or hypertension; 37% had both diabetes and hypertension; and 23% had diabetes only. Of the patients with MIAC , 64.6% over 60 had diabetes. It appears that MIAC occurs infrequently but most often with advancing age, and that diabetes and hypertension act to further predispose to its occurrence.

Adult↗
PubMed1982

Tumor location and detectability in mammographic screening.

The adequacy of a film mammogram that does not visualize the retromammary space or ribs has concerned radiologists. The 79 prevalent cancers detected in the 10,000 self-referred woman at the University of Michigan Breast Cancer Detection Demonstration Project were analyzed for number of films required to detect the cancer, relationship of the cancer to the posterior edge of the film, number of occult lesions, tumor size, histologic type, sensitivity of detection method, and number of interval carcinomas. The mammograms were obtained using a dedicated mammographic machine and the upright position, with visualization of the anterior axillary fold on the mediolateral view. The ribs were not imaged. Of the 79 cancers, 76 were detectable on the mammogram. All were visualized on the mediolateral view, while three were not imaged on the craniocaudal view. Twelve percent of the cancers were within 1 cm of the posterior edge of the film. Only six "interval" carcinomas were found in the 10,000 patients within the year of the initial examinations; these women had dense P2 or DY mammographic parenchymal patterns. The detected cancers were smaller and had a significantly higher percentage of noninvasive cancers than in a symptomatic clinical population. Thus, properly exposed film mammograms using vigorous breast compression examine the breast adequately without visualizing the ribs.

Adult↗
PubMed1980

Association between mammographic parenchymal pattern classification and incidence of breast cancer.

Wolfe has suggested that the mammographic parenchymal patterns can be used to identify a group with high incidence of breast cancer. To evaluate this claim, mammograms of women with breast cancer that was detected at the University of Michigan Breast Cancer Detection Demonstration Project have been classified and compared with a randomly selected control group from the same project. The basic mammographic classifications as defined by Wolfe were used with further refinements made in the DY and QDY groups. The mammographic classifications have been grouped according to the degree of density and age. For all ages combined, our dense classifications (DY1, DY2, DYC-, QDY2) show a higher incident rate, 22/1000,than the lucent classification (N1, P1, and QDY1),9/1000,(P less than .01), although not to the degree suggested by Wolfe. This difference is statistically significant (P less than .01); the higher risk is markedly increased for women under 50 years of age (P less than .005). After age 50 the higher risk associated with the dense breast seems to disappear (P less than .13). However, this might be a consequence of women who were in a dense classification at an earlier age who subsequently changed to a lucent classification later in life. Because the percentage of lucent breasts increases with age there is a higher absolute number of cancers (55%) in this group of women past 50; these women cannot be neglected in screening. Our results suggest the following guidelines for clinical evaluation: (1) Careful mammographic and clinical follow-up for any woman with a dense breast at any age. (2) Careful mammographic and clinical follow-up past 50 regardless of breast classification. (3) Women with lucent breasts under age 50 represent a low risk category and may not require as frequent a follow-up as the other mammographic types.

Adult↗
PubMed1977

Percutaneous needle localisation of breast lesions prior to biopsy: analysis of failures.

Mammography can detect clinically occult breast cancer. But with minimal or no physical findings the lesion can be quite difficult for the surgeon to find within the recumbent breast at biopsy. Percutaneous needle localisation, the placement of a needle in or in the vicinity of such a clinically silent lesion, provides an internal landmark to assist the surgeon. Review of our experience of 90 procedures using this technique disclosed a success rate of approximately 90%. The biopsies diagnosed 14 cancers before local or distant metastasis could be found. The eleven of the fourteen who had axillary dissection were found to have negative nodes. Identifiable causes of failure were sought and discussed in the 7 documented failures. Faulty needle placement was judged noncontributory in all but one case. Needle movement between time of placement and time of biopsy could never be excluded and is in fact suspected in two failures. Immediate re-sampling, or larger initial specimens would have salvaged the procedure in most instances of failure. We feel poor communication and poor mutual understanding of the localization procedure to be the major contributing cause of failure. Even so, we have been able to use the technique with 90% success. The development of mammography brought with it the opportunity to detect small non-palpable carcinomas and the surgical problem of removing them at biopsy. While the suspect lesions identified by mammography are frequently benign, the cancers found are usually small and some only microscopic in size. The literature contains many descriptions of various techniques for localising such lesions prior to biopsy. We are reporting our experience with percutaneous needle localisation. To our knowledge, we have the distinction of being the first to report difficulty with a localisation technique and will analyse possible reasons. Some of the problems are common to all the localisation techniques.

Adult↗
PubMed1977

A simple device for dependent compression mammography.

The authors describe an inexpensive device which displaces the dependent breast from the chest wall for optimum and uniform compression of breast tissue during mammography. Exposure is reduced, detail is enhanced, and superimposed structures are spread out. The filming time is about five minutes, and repeat or additional views are rarely necessary. The authors feel that by using this device, they have not missed any posterior lesions in more than 10 years of use. Even dense breasts are adequately visualized with this technique.

Female↗
PubMed1976

Criteria for obtaining and interpreting breast thermagrams.

The thermal and graphic criteria which should be used to evaluate breast thermograms are outlined. Thermograms are then categorized as normal, suspicious, or abnormal on the basis of the criteria outlined. It is hoped that these criteria can be used widely to standardize breast thermographic evaluation.

Breast Neoplasms↗
PubMed1974

Percutaneous needle localization of clustered mammary microcalcifications prior to biopsy.

Mammography occasionally reveals the presence of suspicious appearing clustered microcalcifications without an associated mass. Clinical localization of these microcalcifications within the breast is difficult, even using the 2 dimensional effect of a mammogram. Percutaneous needle localization of these microcalcifications is recommended for its accuracy, patient acceptance, and reduction in size of the biopsy specimen. No complications of this procedure have been encountered.

Biopsy↗
PubMedDate not supplied

Early detection of breast cancer.

Breast cancer is the most common malignancy in North American women. The incidence rate is increasing by about 2% annually, while the mortality rate has remained stable for 50 years. Screening by physical examination and mammography can decrease the mortality rate in women over 50 by 30%. The screening process is rewarding, but meticulous attention to detail is required in both the physical and mammographic assessment in order to define significant abnormalities.

Adult↗