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Early-life exposures may influence the development of breast cancer. The authors examined the association of childhood and adolescent anthropometric factors, physical activity levels, and diet with adult mammographic breast density, a strong risk factor for breast cancer. Women in the Minnesota Breast Cancer Family Study cohort who had undergone mammograms but had not had breast cancer (n=1,893) formed the sample. Information on adolescent exposures, including relative height, weight, and physical activity at ages 7, 12, and 18 years and diet at age 12-13 years, was self-reported during two follow-up studies (1990-2003). Mammographic percent density was estimated using a computer-assisted thresholding program. Statistical analyses were performed using linear mixed-effects models with two-sided tests. Positive associations with height at ages 7 (p<0.001), 12 (p<0.001), and 18 (p<0.001) years and percent density were evident overall and within menopausal status categories. The minimum difference in percent density between the tallest and shortest girls was 3 percent, with a maximum of 7 percent. Weight at age 12 years (p=0.005) and adiposity at age 12 years (p=0.005) were both inversely associated with adult percent density. Adolescent physical activity and diet were unrelated to percent density. These results suggest that adolescent height, a known risk factor for breast cancer, is also associated with mammographic percent density.

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It is shown that a spin-echo sequence may be used to acquire T(2)-weighted, high-resolution, high-SNR sections at quasi-real-time frame rates for interactive, diagnostic imaging. A single-shot fast spin-echo sequence was designed which employs driven equilibrium to realign transverse magnetization remaining at the final spin echo. Driven equilibrium is shown to improve T(2) contrast at a given TR, or conversely to reduce TR by approximately 1000 msec and thus increase temporal resolution while maintaining a given level of contrast. Wiener demodulation of k-space data prior to reconstruction is shown to reduce blurring caused by T(2)-decay while constraining noise often associated with other inverse filters. Images are continuously acquired, reconstructed, and displayed at rates of one image every one to two seconds, while section position and contrast may be altered interactively. The clinical utility of this method is demonstrated with applications to dynamic pelvic floor imaging and interactive obstetric imaging.

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The aim of this work was to investigate the effect of mammographic acquisition parameter variations on the estimation of percent density (PD) produced by a particular semiautomated algorithm. The PD algorithm requires the user to specify a threshold pixel value segmenting breast tissue of greater and lesser density. A whole breast specimen was imaged using a variety of acquisition techniques, and the image data were processed as prescribed by the PD algorithm. PD estimates for all possible values of the user threshold were calculated for all the images. The image data were normalized so that PD varied between 30% and 80% over a fixed threshold range of 23, and a PD value of 50% was obtained for a threshold value of 195. PD differences between all the images and a baseline standard mammographic acquisition technique were calculated. We also estimated PD differences caused by small (3%) variations in operator selection of the threshold value. We found that the largest differences in PD involved changes in the density control of the mammography unit, and changes in the detector (either film type or computed radiography). The maximum PD differences due to technique were all less than 10%, with root-mean-square (RMS) variations less than 4%. PD differences due to operator variation were 24% (maximum) and 6.1% (RMS). These findings suggest that PD differences due to mammographic technique will be considerably less than those inherent to the technique, due to operator variation. All of these estimates are likely larger than differences seen in practice since optimization of the threshold by the operator was not considered in this analysis.

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Ultrasonography (US) is the modality of choice for prenatal screening, but occasionally additional imaging information is needed. Magnetic resonance (MR) imaging is an attractive alternative but until recently has been limited by motion artifact. Single-shot fast spin-echo MR imaging was used to depict normal and abnormal anatomy in 26 fetuses. Thirteen studies were performed for maternal indications and 13 were performed to evaluate fetal abnormalities identified or suspected at US. Three of the fetal abnormalities involved the central nervous system (CNS) and 10 involved other anatomic sites. Results were correlated with findings at postnatal clinical examination, imaging, and pathologic analysis. MR imaging demonstrated normal fetal anatomy without substantial motion artifact. CNS structures were well visualized as early as 18-20 weeks gestation, as were most other normal anatomic structures except the heart. MR imaging also allowed characterization of a variety of abnormalities of the CNS (Arnold-Chiari malformation, Walker-Warburg syndrome, amniotic band syndrome) as well as of other structures (renal agenesis, multicystic dysplastic kidney, abdominal masses, severe limb-body wall defect, clubfoot with arthrogryposis, diaphragmatic hernia). US findings were confirmed in most cases, and additional information about the precise diagnosis or the severity or location of the anomaly often helped guide clinical management. Single-shot fast spin-echo MR imaging of the fetus is a useful adjunct to US in difficult diagnostic situations.

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PURPOSE: To evaluate the role of transcervical fallopian tube catheterization in restoring tubal patency after ligation reversal surgery. MATERIALS AND METHODS: Twenty-four women with tubal obstruction after ligation reversal surgery underwent selective salpingography and tubal recanalization. RESULTS: Patency was established in 26 (68%) of 38 anastomotic tubes without complication. In the 13 patients who were followed up and who could conceive only via a recanalized anastomotic tube, there were six (46%) pregnancies: two (15%) successful uterine pregnancies, two (15%) early spontaneous abortions, and two (15%) tubal pregnancies. The mean time from procedure to conception was 2 months. CONCLUSION: Patency of fallopian tubes not visualized at hysterosalpingography after ligation reversal surgery can be established 68% of the time with selective salpingography. In some patients, selective salpingography can be therapeutic. If subsequent conception occurs in these patients, it occurs shortly after the catheterization procedure.

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BACKGROUND: The proper evaluation of patients with pancreatic cystic neoplasms remains controversial. Although computed tomography (CT) and sonography can differentiate the majority of these tumors, needle aspiration and biopsy can be helpful in selected patients. The purpose of this study was to (1) determine the sensitivity of needle aspiration and biopsy of cystic pancreatic neoplasms, (2) assess the complications after needle aspiration and biopsy, and (3) assess the indications for needle aspiration and biopsy by using the radiographic appearance as a guide. METHODS: The histories, imaging studies, and pathologic specimens of 18 patients with serous cystadenoma (10 patients) or mucinous cystic tumor (eight patients) of the pancreas who also underwent CT-guided (n = 16), sonographically guided (n = 3), or intraoperative (n = 4) needle biopsy (n = 23 total biopsies) between 1976 and 1996 were retrospectively reviewed. RESULTS: The histologic diagnosis of the serous subtype was made with needle aspiration and biopsy in five of 10 patients with serous cystadenoma. The histologic diagnosis of the mucinous subtype was made with needle aspiration and biopsy in six of eight patients with mucinous cystic neoplasms. Of the 23 biopsies performed, one patient experienced significant intraperitoneal hemorrhage. Indications for needle biopsy include an atypical cystic mass on diagnostic imaging studies, confirmation of a serous cystadenoma before observation, and confirmation of mucinous cystadenocarcinoma in patients with nonresectable disease. CONCLUSION: Needle biopsy and aspiration is a helpful and safe procedure to aid in the diagnosis of cystic pancreatic neoplasms before surgery.

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OBJECTIVE: We present the MR imaging appearance of three cases of pathologically proven placental site trophoblastic tumor (PSTT), a potentially malignant but rare form of gestational trophoblastic disease. CONCLUSION: In our series, PSTT presented as myometrial masses that were isointense to healthy myometrium on T1-weighted images and isointense to slightly hyperintense on T2-weighted images. No associated cystic spaces or prominent blood vessels were identified. These MR findings are not specific, and the diagnosis of PSTT is made from biopsy specimen. In two cases, PSTT was invisible sonographically, and accurate localization with MR imaging allowed the patients to be treated with hysterotomy rather than with hysterectomy.

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PURPOSE: To analyze the natural history, clinical importance, and need for follow-up in patients with discrete calcifications in otherwise ultrasonographically (US) normal ovaries. MATERIALS AND METHODS: US scans obtained in 28 women with ovarian calcifications but without masses or other structural abnormalities were retrospectively reviewed. Follow-up findings were available in 15 women (mean age, 38.0 years; range, 26-72 years). RESULTS: Two of the 15 women had trilateral calcifications. Thus, 17 ovaries had focal calcifications. Histopathologic confirmation was obtained in 10 cases; follow-up US findings, five cases; and follow-up laparoscopic findings, two cases. In 13 (76%) of the 17 ovaries, calcifications were not clinically important. In four (24%) of the 17, the calcification was the initial or only manifestation of a neoplasm. Lesions were benign in all four of these ovaries: There was one dermoid, one mucinous cystadenoma, and two adenofibromas. CONCLUSION: Until more data are available, findings of calcifications in ovaries with otherwise normal US findings warrant some form of follow-up.

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A retrospective review of 211 computed tomographic (CT)-guided and 58 ultrasound (US)-guided biopsies of pancreatic lesions performed between 1985 and 1989 was undertaken to evaluate the accuracy of diagnosis and the number of complications. Combined CT and US accuracy in the diagnosis of malignancy was 93%. CT-guided biopsies had an accuracy of 86%, and US-guided biopsies had an accuracy of 95%. Accuracy was higher with larger masses (> 3.0 cm, 92%; < or = 3 cm, 81%) and larger needle sizes (16-19 gauge, 92%; 20-22 gauge, 85%) and when the mass was located in the body or tail of the pancreas (93%) rather than the head (84%). Major complications developed in three cases (1.1%). No biopsy-related deaths occurred. Needle passage through the gastrointestinal tract, including the colon, did not cause complications.

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We evaluated 114 hospital admissions for diabetic ketoacidosis (occurring in 78 patients) retrospectively by using the Mayo Clinic medical records system. Initial plasma glucose and serum bicarbonate values were examined by using regression analysis. No correlation was found between these two measurements (r = -0.03). The reason for this dissociation between hyperglycemia and hyperketonemia needs further elucidation, but it may be related to impaired hepatic glucose production in some patients.

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An established obsessive compulsive disorder (OCD) in a twenty-six-year-old woman, characterized by obsessional fear of rat germs and ritualistic cleansing, was observed to worsen during pregnancy. The patient's OCD had followed a fluctuating course for three years but she had not previously experienced a decompensation of such duration and severity. During her pregnancy she became depressed and suicidal, was unable to care for her family and spent the majority of her confinement in the hospital. Several mechanisms are discussed which might explain the exacerbation.

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Exposure to whole cigarette smoke from reference cigarettes results in the prompt (peak activity is 6 hrs), but fairly weak (similar to 2 fold), induction of murine pulmonary microsomal monooxygenase activity. This activity can be detected by using as substrates either benzo(a)pyrene or ethoxyresorufin, and can be inhibited by treatment with cycloheximide or actinomycin D. Unlike the induction of pulmonary monooxygenases following intratracheal administration of 3-methylcholanthrene, these cigarette smoke-induced increases were not unequivocally linked to the Ah locus. Whole smoke condensate and fractions derived from these condensates can; a) induce pulmonary monooxygenase activity, b) inhibit benzo(a)pyrene metabolism in vitro, c) be metabolized to forms mutagenic to Salmonella typhimurium tester strains TA153, or TA98, d) transform C3H 10T1/2 cells in vitro, and e) enhance the carcinogenicity of benzo(a)pyrene in murine pulmonary tissue. A potentially important observation is that whereas hepatic tissue is capable of activating whole cigarette smoke condensate to mutagenic forms in vitro, murine pulmonary tissue does not seem capable of such activation. Although these pulmonary-derived tissue homogenates have significant AHH activity and can metabolize Aflatoxin B1, 2-aminofluorene and 7, 8-dihydro-7,8-dihydroxybenzo(a)pyrene to mutagenic forms, these homogenates fail to activate both cigarette smoke condensate and the pro-mutagen, 6-aminochrysene. These results are discussed with reference to the concept that whole cigarette smoke may be both a potential "initiator" and "promotor" of lung cancer in mice, and that this latter property may be the most important in determining cancer risk.

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