John A. Cutrone

Comparison of electron beam computed tomography scanning and magnetic resonance imaging quantification of right ventricular mass: Validation with autopsy weights

RATIONALE AND OBJECTIVES We compared, in the same human hearts, the ability of magnetic resonance (MR) imaging and electron beam computed tomography (CT) scanning to accurately quantify the free wall and septal components of right ventricular (RV) mass. METHODS Eleven hearts extracted at autopsy were subjected to MR imaging and electron beam CT scanning in short-axis projections. Regression analyses of mass determinations obtained by manual planimetry MR imaging and electron beam CT scanning and autopsy weights were performed. RESULTS RV free wall mass by both MR imaging (53.4 +/- 19.1 g) and electron beam CT scanning (53.9 +/- 20.4 g) correlated well with autopsy weight (57.7 +/- 20.2 g). Regression analysis showed a strong correlation for MR imaging (r = .88, slope = .88, standard error the estimate [SEE] = 7.2 g, p < .001) and electron beam CT scanning (r = .95, slope = .95, SEE = 6.6 g, p < .001). RV septal mass by MR imaging (10.8 +/- 3.5 g) and electron beam CT scanning (7.1 +/- 2.4 g) correlated less well with the autopsy weight (12.5 +/- 6.5 g). Regression analysis showed a fair correlation for MR imaging (r = .45, slope = .83, SEE = 2.05 g, p = .001) and a poor correlation for electron beam CT scanning (r = .46, slope = .17, SEE = 2.25 g, p = .57). CONCLUSION Both MR imaging and electron beam CT scanning accurately predict RV free wall mass but have difficulty predicting the septal component. Because the septal component constitutes only a small proportion of the total RV mass, determinations of RV mass should be based solely on the free wall component.

Tc-99m Sestamibi Scintimammography for the Evaluation of Breast Masses in Patients with Radiographically Dense Breasts.

Abstract: The objective of this study was to evaluate the usefulness of technetium‐99m sestamibi (MIBI) scintimammography for the diagnosis of breast cancer in patients with palpable breast masses that cannot be adequately evaluated by mammography due to the presence of radiographically dense breasts. At 5 minutes after intravenous injection of MIBI, scintimammograms were obtained in 80 patients who had grade 3 or 4 glandular density on mammograms and a palpable breast mass. Excisional biopsy or FNA biopsy was obtained in 68 lesions in 67 patients. Scintimammography (22 true positive, 4 false positive, 41 true negative, 1 false negative) resulted in a sensitivity of 95.6%, specificity 91.1%, positive predictive value 84.6%, and negative predictive value 97.6%. Mammography (19 true positive, 21 false positive, 24 true negative, 4 false negative) resulted in a sensitivity of 73.9%, specificity 53.3%, positive predictive value 44.7%, and negative predictive value 80%. MIBI scintimammography has a higher sensitivity and specificity than mammography in patients with radiographically dense breasts. It is useful as an adjunct to mammography in those patients with radiographically dense breasts for the characterization of palpable masses. Although sensitivity of mammography in this cohort was high, its specificity was significantly lower than scintimammography. If validated in prospective studies it could provide a safe way of avoiding a breast biopsy in patients with benign findings on clinical exam, mammography, and needle aspiration cytology.

RIGHT VENTRICULAR MASS MEASUREMENT BY ELECTRON BEAM COMPUTED TOMOGRAPHY: VALIDATION WITH AUTOPSY DATA

RATIONALE AND OBJECTIVESValidation of right ventricular mass quantitation by electron beam computed tomography in humans has not been performed. The ability of electron beam computed tomography to accurately determine the septal component of the right ventricle also has not been determined. This article addresses both issues. METHODSTwenty human adult hearts obtained at autopsy were scanned by electron beam computed tomography in a short-axis projection. Planimetry of the right ventricular free wall and septal components of each slice was performed and summed to determine right ventricular mass. These measurements were compared against comparable measurements obtained by autopsy weights of the hearts. RESULTSRight ventricular free wall weights by electron beam computed tomography (53.9 ± 18.4 g) correlated well (slope = .92, r = .92, standard error of the estimate = 7.4 g, P < .001) with autopsy weights (55.8 ± 18.4 g). Right ventricular septal weights by electron beam computed tomography (6.1 ± 2.3 g) correlated poorly (slope = .04, r = .11, standard error of the estimate = 2.4 g, P = .65) with autopsy weights (13.9 ± 6.3 g).CONCLUSIONS. Electron beam computed tomography quantitation of right ventricular mass is accurate in humans if only the free wall and not the septal component is utilized.

Observer Agreement of Mammographic Interpretation

Abstract: The purpose of this study was to determine the inter‐ and intraobserver agreement of mammographic interpretation among three board‐certified radiologists with different levels of expertise in mammography who interpret mammograms, and to use the data to improve quality assurance of mammography.

Investigation of abnormal appearing thyroid glands on Tc-99m sestamibi breast scintimammography.

Of 507 breast scintimammograms performed using Tc-99m sestamibi, 34 patients were incidentally found to have abnormal appearing thyroid glands. The authors sought to investigate the clinical significance and/or ascertain an extraneous causative factor for these findings. One cold thyroid nodule was detected and was proven benign through biopsy. Two cases of subacute and chronic thyroiditis were proven, and it is possible that additional patients had this disease process. Focal areas of increased thyroid Tc-99m sestamibi uptake were observed in eight patients and probably represent parathyroid adenomas, nonautonomous hyperfunctioning thyroid nodules, or nontoxic multinodular goiter. The results did not yield an extraneous causative factor, underlying pathology, or clinically significant disease in all of the patients investigated, but the findings suggest a need for careful evaluation of any unusual uptake in the thyroid gland and the rest of the image. The authors do not recommend investigation of all abnormal appearing thyroid glands on Tc-99m sestamibi scintimammography. However, clinical correlation should be recommended.