Peter L. Davis

Breast cancer measurements with magnetic resonance imaging, ultrasonography, and mammography.

SummaryBackground: Accurate measurement of the size of breast cancers becomes more important as breast cancer therapy advances. This study reports the accuracy of magnetic resonance imaging (MRI), ultrasonography and mammography for measuring the largest breast cancer diameter in comparison to the pathology measurement.Materials and methods: Fourteen breast cancers were examined in 13 women with MRI, ultrasonography and mammography. The age range was 31–73 (mean 56). Six of the cancers were in premenopausal women. The MRI was performed with the intravenous injection of gadolinium based contrast agent and a three dimensional fast spoiled gradient echo sequence with fat suppression. The largest cancer diameter was measured with each imaging technique and compared to the largest cancer diameter measured at pathology.Results: At pathological examination cancers ranged from 0.6 to 6 cm (mean 2.2) in largest diameter. MRI measurements had the highest correlation coefficient (r = 0.98) and the smallest standard error (0.34). Ultrasonography measurements had a correlation coeffient of r = 0.45 and a standard error of 0.78. Mammography measurements had a correlation coefficient of r = 0.46 and a standard error of 1.04.Conclusions: MRI was more accurate than ultrasonography and mammography in measuring the largest cancer diameters in this group of women. This was particularly evident for several larger cancers, and a postchemotherapy cancer.

Budd-Chiari syndrome: Imaging with pathologic correlation

We retrospectively evaluated 21 patients with Budd-Chiari syndrome who underwent liver transplant. The pathological findings were correlated with imaging studies that included computed tomography (CT) in all cases, sonography in 20, and magnetic resonance (MR) in 15. Pathological features of Budd-Chiari syndrome in subacute or chronic form, such as parenchymal fibrosis, hemorrhage, and congestion, were found in all resected livers. These occurred usually in conjunction with restricted hepatic veins due to thrombosis or fibrosis with partially recanalized lumen. The status of hepatic veins was correctly assessed and correlated with pathology in 13 of 20 patients who had sonograms, in 12 of 15 patients who had MR, and in nine of 18 patients with contrast-enhanced CT scans. Patency of the inferior vena cava was well seen by all three modalities; parenchymal abnormalities were best visible on CT (19 of 21), while ascites, caudate lobe enlargement and collateral vessels were best detected with MR or CT. We conclude that each imaging modality offers certain values and limitations in the assessment of vascular or parenchymal findings in Budd-Chiari syndrome.

Magnesium supplementation during cardiopulmonary bypass to prevent junctional ectopic tachycardia after pediatric cardiac surgery: A randomized controlled study

OBJECTIVES We analyzed the role of magnesium sulfate (MgSO(4)) supplementation during cardiopulmonary bypass in pediatric patients undergoing cardiac surgery, assessing the incidence of hypomagnesemia and the incidence of junctional ectopic tachycardia. METHODS We performed a randomized, double-blind, controlled trial in 99 children. MgSO(4) or placebo was administered during the rewarming phase of cardiopulmonary bypass: group 1, placebo group (29 patients); group 2, 25 mg/kg of MgSO(4) (30 patients); and group 3, 50 mg/kg of MgSO(4) (40 patients). RESULTS At the time of admission to the cardiac intensive care unit, groups receiving MgSO(4) had significantly greater levels of ionized magnesium (group 1, 0.51 + or - 0.07; group 2, 0.57 + or - 0.09; group 3, 0.59 + or - 0.09). Hypomagnesemia before bypass was common (75%-86.2%) and not significantly different among the groups. The proportion of hypomagnesemia decreased significantly at admission to the cardiac intensive care unit in groups receiving MgSO(4) (group 1, 77.8%; group 2, 63%; group 3, 47.4%). Patients receiving placebo (group 1) had a significantly greater occurrence of junctional ectopic tachycardia than groups receiving MgSO(4) (group 1, n = 5 [17.9%]; group 2, n = 2 [6.7%]; group 3, n = 0 [0%]). Age (<1 month), Aristotle score (>4), and history of cardiac failure were associated with junctional ectopic tachycardia. None of the patients with those characteristics in group 3 had junctional ectopic tachycardia. No association was found between study groups and the Pediatric Risk of Mortality score or length of stay in the cardiac intensive care unit. CONCLUSIONS Supplementation with MgSO(4) during cardiopulmonary bypass seems to reduce the incidence of hypomagnesemia and junctional ectopic tachycardia at admission to the cardiac intensive care unit. This effect seems to be dose related.

Detectability of Hepatomas in Rat Livers by Nuclear Magnetic Resonance Imaging

: NMR imaging of rats with implanted hepatomas in the liver demonstrates that under the imaging conditions of this study tumors of over 8 mm2 in area can be detected with high accuracy. Compared to normal liver, approximately 70% of these tumors had a combination of relaxation times (T1-T2) that could be uniquely identified as tumors, while the other 30% demonstrated relaxation time combinations that overlapped those previously found for abscesses, brain, and hematomas.

Hyperintense cirrhotic nodules on MRI

Descriptions of regenerating nodules of cirrhosis indicate that they are often isointense to liver parenchyma on magnetic resonance imaging (MRI). Regenerating nodules of cirrhosis can occasionally appear hypointense on all MRI sequences due to iron deposition within the nodules. We reviewed 21 cases of pathologically proven mixed or macronodular cirrhosis using MRI. In five patients, nodules appeared as hyperintense to liver parenchyma on short TR/TE images and were isointense on long TR/TE or GRASS images. In another five cases, nodules appeared hypointense on either long TR/TE or GRASS images, and corresponding hypointense nodules were observed on short TR/TE images in one of these patients. Our findings suggest that regenerating nodules of cirrhosis may have a more variable appearance on short TR/TE images.

Magnetic resonance imaging detection and wire localization of an ‘occult’ breast cancer

SummaryAn occult breast cancer was detected and wire localization performed using magnetic resonance imaging.

Indicator dilution time-activity curves demonstrated by rapid magnetic resonance imaging techniques and paramagnetic contrast agent.

Indicator dilution time-activity curves are demonstrated using magnetic resonance imaging (MRI) as the detector and a paramagnetic contrast agent as the indicator. Manganese chloride was injected into a flow phantom. The nuclear magnetic resonance (MR) intensity was measured downstream. Several flow rates were used. The observed MR intensity decreased as the paramagnetic indicator passed through the imaging plane. The qualitative changes of the MR intensity decrease varied in accordance with indicator dilution theory. The equations for gradient refocused echoes, paramagnetic compound relaxation changes, and the indicator dilution analysis were combined and evaluated. Quantitative analysis demonstrates several problems in its implementation.

Magnetic resonance imaging in breast cancer staging.

For many solid carcinomas, high-resolution cross-sectional imaging has changed cancer staging, the evaluation of therapeutic response, the detection of recurrence, and even how therapy is selected and performed. Such imaging has not yet had similar effects on breast cancer. Evaluations of therapeutic response in breast carcinomas have been impeded by the current limited methods of evaluating breast tumor size and extent: clinical palpation, ultrasonography, and mammography. The use of magnetic resonance imaging (MRI) of the breast in the evaluation of breast tumors brings the advantages of high-resolution cross-sectional imaging to breast cancer staging and treatment evaluation and is likely to greatly enhance research efforts in this complex disease. MRI of the breast has evolved to be the most accurate noninvasive technique for local staging of breast cancer. MRI is most accurate in measuring tumor size and detecting multicentric disease. These staging characteristics affect the selection of therapy and initial determination of prognosis; therefore. MRI of the breast can change the assessment of fundamental parameters on which treatment is selected. Because clinical trials of new cancer treatments are predicated on proper and accurate characterization of the tumor, MRI also should affect how clinical trials are performed and evaluated.

The inflammatory bowel disease Live Interinstitutional and Interdisciplinary Videoconference Education (IBD LIVE) series

Background:Managing patients with inflammatory bowel disease requires multidisciplinary coordination. Technological advances have enhanced access to care for patients and improved physician interactions. The primary aim of our project was to convene diverse institutions and specialties through a multisite virtual conferencing platform to discuss complex patient management. Methods:The case conference is designed to include multiple institutions to exchange ideas, review evidence-based data, and provide input on the management of patients with Crohns disease and ulcerative colitis. Technology is supplied and coordinated by an information technology specialist and Chorus Call, Inc., an international teleconferencing service provider. The Inflammatory Bowel Disease Live Interinstitutional Interdisciplinary Videoconference Education (IBD LIVE) initiative is accredited by the University of Pittsburgh Medical Center (UPMC) Center for Continuing Education in the Health Sciences for 1 AMA PRA Category 1 Credit per weekly session. Results:IBD LIVE began in 2009 comprising only adult gastroenterology and pediatric gastroenterology from UPMC Presbyterian and Childrens Hospitals. Participation steadily increased from 5 sites in 2010 to 11 sites in 2014. Maximum attendance for a single conference was 73 participants with a median of 48. The Continuing Medical Education scores (1 = worst to 5 = best) have a high median overall score (4.6, range 3.2–5.0) with positive responses with regard to the degree to which the conference changed practice. Conclusions:IBD LIVE has been successful and continues to grow. Implementation of the Crohns and Colitis Foundation of America Virtual Preceptor Program using the IBD LIVE platform will provide expanded national physician access to this professional education activity.

Anaphylactoid reactions to the nonvascular administration of water-soluble iodinated contrast media.

OBJECTIVE Anaphylactoidlike reactions occur during the nonvascular administration of iodinated contrast media. Many of these reactions have been severe. These reactions have occurred with many procedures, including gastrointestinal imaging, cystography, sialography, and hysterosalpingography. CONCLUSION This article reviews reports of these reactions. It also reviews what the literature recommends concerning how to deal with individuals undergoing these procedures who are at a higher risk for anaphylactoidlike reactions.