Chronic heart failure: global left ventricular perfusion and coronary flow reserve with velocity-encoded cine MR imaging: initial results

PURPOSE: To quantify and compare global left ventricular (LV) perfusion and coronary flow reserve (CFR) in patients with chronic heart failure and in healthy volunteers by measuring coronary sinus flow with velocity-encoded cine (VEC) magnetic resonance (MR) imaging. MATERIALS AND METHODS: MR measurements were performed in 10 consecutive patients with chronic heart failure due to coronary artery disease and in 10 volunteers. Global LV perfusion was quantified by measuring coronary sinus flow in an oblique imaging plane perpendicular to the coronary sinus with non-breath-hold VEC MR imaging. LV mass was measured by means of cine imaging that encompassed the heart. LV perfusion was calculated from coronary sinus flow and mass. CFR was measured from LV perfusion at rest and that after infusion of dipyridamole. Analysis of covariance was used to determine differences between groups. Differences within groups were analyzed by means of the Student t test for paired data. Regression analysis was used to determine correlation between CFR and LV ejection fraction. RESULTS: At rest, LV perfusion was not significantly different in patients with chronic heart failure (0.46 mL/min/g +/- 0.19) and volunteers (0.52 mL/min/g +/- 0.21, P =.54). After administration of dipyridamole, LV perfusion was less than half in patients with chronic heart failure compared with that in volunteers (1.07 mL/min/g +/- 0.64 vs 2.19 mL/min/g +/- 0.98) (P =.03). CFR was severely reduced in patients with chronic heart failure compared with that in volunteers (2.3 +/- 0.9 vs 4.2 +/- 1.5, P =.01). A moderate but significant correlation was found between CFR and LV ejection fraction (r = 0.54, P =.02) CONCLUSION: Combined cine and VEC MR imaging revealed that patients with chronic heart failure have normal LV perfusion at rest but severely depressed LV perfusion after vasodilation. Impaired CFR may contribute to progressive decline in LV function in patients with chronic heart failure.     

Mammographic and clinical predictors of drainage patterns in breast lymphoscintigrams obtained during sentinel node procedures

PURPOSE: The authors' purpose was to explore the association between mammographic findings and drainage patterns on lymphoscintigrams obtained during sentinel node procedures for breast carcinoma. MATERIALS AND METHODS: From July 1997 to March 2000, 132 patients with breast cancer who were included in a prospective mammography-pathology correlation and staging database were imaged 2 hours after perilesional injection of 1 mCi filtered (0. 22 microm) Tc-99m sulfur colloid (4 ml volume) before sentinel node procedures. RESULTS: Sixty-four percent of the scans showed axillary drainage only, 9% showed axillary and internal mammary drainage, and 4% revealed internal mammary drainage only. Twenty-three percent of scans showed no drainage. Of the patients who showed drainage, 17% showed drainage to the internal mammary basin, and 5% showed this exclusively. Internal mammary drainage was seen in 18% (10 of 57) of lateral, 21% (6 of 29) of medial, and 14% (1 of 7) of subareolar lesions (P = NS). No drainage was seen in 22% of patients with predominantly fatty mammographic parenchymal density (>50%) compared with only 8% of patients with predominantly dense (>50%) parenchyma (P < 0.05). Failure to show drainage was more common in women older than 50 years (P < 0.05). Axillary sentinel nodes were identified surgically in 73% of patients with negative scan findings. There was no significant association between scintigraphic drainage and mammographic soft tissue tumor size and appearance, histologic findings, or axillary node status. CONCLUSIONS: Dense mammographic parenchyma and age less than 50 years are associated with identification of lymphatic drainage on lymphoscintigrams performed before sentinel node procedures in 91% to 92% of patients. Internal mammary drainage, present in 18% of lateral and 21% of medial lesions, may direct therapy to include internal mammary lymph nodes.     

A new and versatile method for determination of thiolamines of biological importance

A method for the separation and quantitation of several important biological thiolamines is described. The procedure employs a C18 reversed-phase HPLC system to separate the dinitrophenyl derivatives of reduced and oxidized glutathione and cysteine and relies on an internal standard, Nepsilon-methyllysine, to minimize experimental error. The method was validated in three matrices (water, HepG2 cell lysates, and mouse liver homogenates) using several criteria. The detector response was linear for the dinitrophenyl derivatives of glutathione, glutathione disulfide, cysteine, and cystine in the concentrations ranging from 10 to 50 nmol/ml. Inter- and intra-day variation, percent recovery in the biological matrices, and limits of detection and quantitation were determined. For the most accurate determination, it is essential that standard curves be produced daily and in the same matrix as that being analyzed.     

Magnetic resonance-guided prostate interventions

We review our experience using an open 0.5-T magnetic resonance (MR) interventional unit to guide procedures in the prostate. This system allows access to the patient and real-time MR imaging simultaneously and has made it possible to perform prostate biopsy and brachytherapy under MR guidance. We review MR imaging of the prostate and its use in targeted therapy, and describe our use of image processing methods such as image registration to further facilitate precise targeting. We describe current developments with a robot assist system being developed to aid radioactive seed placement.