Doppler echocardiography of 119 normal-functioning St Jude Medical mitral valve prostheses: a comprehensive assessment including time-velocity integral ratio and prosthesis performance index.

The purpose of this study was to provide, in a large number of patients, comprehensive Doppler echocardiographic assessment of normal St Jude Medical mitral valve prosthesis function using Doppler-derived hemodynamic variables, including the mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio and prosthesis performance index. The pressure half-time was less than 130 milliseconds in all patients, and all but one patient had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2. There was a significant (P < .001) negative correlation between the prosthesis performance index and prosthesis size. This negative correlation suggests that there is more efficient use of the in vitro geometric orifice area with smaller prostheses.     

Serum protein electrophoresis patterns in chronic lymphocytic leukemia. Clinical and epidemiologic correlations

Serum protein electrophoresis (SPEP) data obtained at diagnosis were available for 98 of 342 patients with chronic lymphocytic leukemia (CLL) identified in a population-based case-control epidemiologic study. Patients tested with SPEP at diagnosis were significantly younger, more likely to have lymphadenopathy, and more likely to have had their conditions diagnosed at a university hospital than those not tested. Four categories of electrophoretic patterns were identified: normal (N = 56), hypogammaglobulinemia (N = 28), hypergammaglobulinemia (N = 11), and monoclonal gammopathy (N = 3). A higher proportion of those with hypergammaglobulinemia were black, and patients with hypergammaglobulinemia and monoclonal gammopathy were more likely to die within the first year following diagnosis than patients in the other SPEP groups. No association was found, however, between SPEP pattern and a clinical staging classification for CLL. These findings suggest that SPEP may be a useful adjunct in categorizing possible subtypes of CLL and developing future clinical staging classifications.     

Failure of ivalon to provide permanent hepatic arterial occlusion

Ivalon (polyvinyl alcohol) is a commonly used embolic agent, generally considered to be permanent. In a patient with the carcinoid syndrome, embolization of hepatic metastases with Ivalon failed to produce permanent occlusion, and recurrent tumor was supplied by many of the same small arteries identified on the original arteriogram. Occasionally, Ivalon may have only a temporary occlusive effect. A possible explanation for this phenomenon is proposed.     

Autosomal recessive distal dystrophy

We describe five new cases of autosomal recessive distal dystrophy (Miyoshi myopathy) and emphasize the distinctive clinical and laboratory features of this unusual muscular dystrophy. Symptoms began at age 15 to 25, the gastrocnemius muscles were selectively involved, and creatine kinase was elevated more than 10 times normal. The EMG showed abundant brief motor units with numerous fibrillations. Dystrophic features without vacuoles were best seen in the biceps femoris muscle. Asymptomatic creatine kinase elevation was present years prior to the development of weakness. The disorder appears to be inherited in an autosomal recessive pattern. Miyoshi myopathy can be distinguished from other distal muscular dystrophies. We propose a new classification for the distal muscular dystrophies.     

Cross-calibration of dual-energy X-ray densitometers for a large, multi-center genetic study of osteoporosis

Osteoporosis is a common disease with a strong genetic component characterized by reduced bone mass and an increased risk of fragility fractures. Bone mineral density (BMD) is the most important determinant of osteoporotic fracture risk, but the genes responsible for BMD regulation and fracture are incompletely defined. To enable multi-center studies to examine the genetic influences on BMD there is a requirement to standardize measurements across different manufacturers of bone densitometers, different versions of machines and different normative ranges. This paper describes a method developed to allow near-identical subjects with low age-adjusted BMD (based on Z-scores) to be recruited in 17 centers using 27 different densitometers. Cross-calibration was based on measurements using a European spine phantom circulated to all centers and measured ten times on each individual machine. From theses values an individual exponential curve, based on nominal versus observed BMD, was derived for each machine. As expected, there were large and significant variations in nominal BMD values, not only between scanners from different manufacturers but also between different versions of scanners from the same manufacturer. Hologic scanners tended to underestimate the nominal BMD, while Lunar scanners overestimated the value. Norland scanners gave mixed values over estimating BMD at the lower nominal value (0.5 g/cm²) while underestimating the value at the higher value (1.5 g/cm²). The validity of the exponential equations was tested using hip and spine measurements on 991 non-proband women from a familial osteoporosis study (FAMOS). After cross-calibration there was a considerable reduction in variation between machines. This observation, coupled with the absence of a similar reduction in variation attributable to a linear regression on age, demonstrated the validity of the cross-calibration approach. Use of the cross-calibration curves along with a standard normative range (in the case of this study, the Hologic normative range) allowed age-specific Z-scores to be used as an inclusion criterion in this genetic study, a method that will be useful for other trials where age-specific BMD inclusion criteria are required.     

Brain and spinal cord hemorrhage in long-term survivors of malignant pediatric brain tumors: a possible late effect of therapy

Three children with malignant primary CNS tumors treated with craniospinal radiotherapy developed intraparenchymal hemorrhages a median of 5 years following therapy in sites distant from the primary tumor. Radical surgical procedures disclosed fresh and old hematoma, gliosis, and necrosis in all 3 patients and an aggregation of abnormal microscopic blood vessels in two. No tumor was found. All 3 patients remain in long-term (greater than 10 years) continuous remission.     

Lumbar spondylolysis and spondylolisthesis in college football players. A prospective study

A prospective study was done on Indiana University freshman football players to determine if the incidence of lumbar spondylolysis and spondylolisthesis followed the pattern of previous studies. Using x-ray film evaluation, 145 freshman players were followed through their careers from 1978 to 1983. As in previous studies, a higher percentage (15.2%) of the defect was found than exists in the general population. However, only 2.4% of these players developed the problem in college, a much lower figure than previously found. Affected team members played a variety of positions. In addition to spondylolysis, some other problems, such as spina bifida occulta, were found. Theories on the cause of spondylolysis and spondylolisthesis are reviewed, and preventive suggestions such as more careful training and weight lifting are presented.