Variations of the area and shape of the left atrioventricular valve and its cusps and leaflets

Summary Measurement of the areas of the cusps and leaflets of the left atrioventricular valve (LAV) and a study of their shape were performed in 91 normal human hearts, to assess the range of variation and determine the most frequent morphologic pattern. The average areas were as follows: LAV, 904.9 mm²; anterior cusp, 447 mm²; posterior cusp, 457 mm²; anterolateral leaflet, 118.6 mm²; intermediate leaflet, 212.7 mm²; and posteromedial leaflet, 126 mm². The commonest shape of the leaflets of the posterior cusp, proved to be rectangular.

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Variations de la surface et de la forme de la valve atrioventriculaire gauche, de ses cuspides et languettes

Résumé La mesure de la surface des cuspides et des languettes de la valve atrioventriculaire gauche (LAV) et l'étude de leur forme ont été réalisées sur 91 coeurs humains normaux pour évaluer l'éventail des variations et déterminer la disposition morphologique la plus fréquente. Les surfaces moyennes furent les suivantes : LAV 904,9 mm² ; cuspide antérieure 447 mm²; cuspide postérieure 457 mm²; languette antéro-latérale 118,6 mm²; languette intermédiaire 212,7 mm²; languette postéro-médiale 126 mm². La forme la plus répandue pour les languettes de la cuspide postérieure s'est avérée être rectangulaire.

     

Acute primidone overdosage with massive crystalluria.

A patient admitted to the hospital in coma was found to have massive primidone crystalluria. Gas chromatographic analysis of blood and urine for primidone and phenobarbital showed high urine primidone levels and high blood phenobarbital levels. The primidone levels suggest that primidone is rapidly cleared into urine. The high blood phenobarbital levels within 12 hr of overdosage with a history of diphenylhydantoin therapy and without phenobarbital therapy or overdosage suggests that diphenylhydantoin may influence the metabolic conversion of primidone to phenobarbital. The relationship of clinical symptomatology to high levels of primidone and phenobarbital is unclear. Analysis of blood and urine for primidone and phenobarbital and urine for crystals is of value in establishing diagnosis and prognosis in cases of suspected primidone overdosage.     

Typological analysis of U.S. medical schools.

Using multivariate statistical techniques, a large number of variables describing medical school characteristics was reduced to five general dimensions of variation. Patterns of factor scores on these five dimensions served as the basis of a typology of 107 U.S. medical schools. The types of schools so identified were found to be related to the proportions of graduates entering different areas of medicine.     

Mammography in women under age 30: is there clinical benefit?

With the increasing utilization of mammography, young women under age 30 are being referred for mammographic examination more frequently. A review of the mammograms of 76 patients, aged 18-29 years, was conducted to evaluate the clinical utility of the examination in this age group, for whom the probability of malignancy is quite low and the risk of radiation carcinogenesis may not be negligible. In 74% of patients referred for study of a palpable mass, no mass was evident on mammograms. When a mass was seen, the radiographic features did not influence clinical management. Radiologists should inform their clinical colleagues regarding the risks and limitations of mammography in women under age 30 and encourage more frequent utilization of ancillary diagnostic procedures including sonography and diagnostic aspiration.