Pattern recognition of MRSI data shows regions of glioma growth that agree with DTI markers of brain tumor infiltration.

Gliomas are the most common primary brain tumors and the majority are highly malignant, with one of the worst prognoses for patients. Gliomas are characterized by invasive growth into normal brain tissue that makes complete surgical resection and accurate radiotherapy planning extremely difficult. We have performed independent component analysis of magnetic resonance spectroscopy imaging data from human gliomas to segment brain tissue into tumor core, tumor infiltration, and normal brain, with confirmation by diffusion tensor imaging analysis. Our data are consistent with previous studies that compared anomalies in isotropic and anisotropic diffusion images to determine regions of potential glioma infiltration. We show that coefficients of independent components can be used to create colored images for easy visual identification of regions of infiltrative tumor growth.

Exercise limitation in patients with polymyositis.

To examine the hypothesis that patients with inflammatory muscle disease have impairments in cardiac and/or pulmonary function that are masked by peripheral muscle weakness, complete PFTs, echo/Doppler studies and exercise testing were performed in 11 patients with polymyositis. Maximal inspiratory and expiratory pressures and expiratory flow rates were normal. One patient had evidence of restrictive lung disease; two had a reduced Dsb. Seven patients had evidence of pulmonary hypertension. Only three patients had normal aerobic capacity; VO2 max in the other 8 patients was 46 +/- 8 percent of predicted when they stopped exercising. Four patients had a normal O2 pulse; seven patients had a reduced O2 pulse while five of seven patients exceeded 85 percent of their target heart rate. We conclude that while asymptomatic impairments in pulmonary function are uncommon in polymyositis, the incidence of pulmonary hypertension is high, but symptoms may be masked by the peripheral muscle weakness.

Noninvasive cardiovascular studies in patients with inflammatory myopathy.

The authors prospectively performed echocardiographic and Doppler studies on 13 patients with inflammatory myopathy to evaluate ventricular function, to assess valve morphology and function, and to obtain hemodynamic data. No patient had a reduction in left ventricular function or evidence of significant valvular disease. Hemodynamic assessment suggested evidence of pulmonary hypertension in 9 patients. They conclude that cardiomyopathy in association with inflammatory myopathy is unusual and that the suggestion of pulmonary hypertension is unexplained and merits further evaluation.

Left ventricular outflow obstruction by a mitral valve prosthesis: Doppler ultrasound and cardiac catheterization findings.

Left ventricular outflow tract obstruction by a mitral valve prosthesis was noted several years following surgery when symptoms of congestive heart failure occurred. The diagnosis was made using two-dimensional echocardiography and Doppler techniques and confirmed at heart catheterization, using micromanometer tipped catheters.

Pharmacologic therapy of low output syndromes after cardiac surgery.

With the advancement of surgical techniques and myocardial protection we can expect that patients previously felt to be inoperable because of poor ventricular function will be surgical candidates. This group of patients will on occasion develop severe left ventricular dysfunction in the peri-operative period. Optimum management in this setting will require acquisition of haemodynamic data, assessment of ventricular loading conditions and inotropic state and the selection of appropriate drug therapy. Drugs are available with specific haemodynamic profiles and therapy is enhanced by matching the abnormal haemodynamics of patients with an appropriate therapeutic agent. If the patient fails to respond quickly to pharmacotherapy, consideration should be directed toward use of an intra-aortic balloon pump.