In vivo precision of the GE Lunar iDXA for the measurement of visceral adipose tissue in adults: the influence of body mass index.

CoreScan is a new software for the GE Lunar iDXA, which provides a quantification of visceral adipose tissue (VAT). The objective of this study was to determine the in vivo precision of CoreScan for the measurement of VAT mass in a heterogeneous group of adults. Forty-five adults (aged 34.6 (8.6) years), ranging widely in body mass index (BMI 26.0 (5.2) kg/m(2); 16.7-42.4 kg/m(2)), received two consecutive total body scans with repositioning. The sample was divided into two subgroups based on BMI, normal-weight and overweight/obese, for precision analyses. Subgroup analyses revealed that precision errors (RMSSD:%CV; root mean square standard deviation:% coefficient of variation) for VAT mass were 20.9 g:17.0% in the normal-weight group and 43.7 g:5.4% in overweight/obese groups. Our findings indicate that precision for DXA-VAT mass measurements increases with BMI, but caution should be used with %CV-derived precision error in normal BMI subjects.

Variability in heart rate recovery measurements over 1 year in healthy, middle-aged adults.

This study assessed the longer-term (12-month) variability in post-exercise heart rate recovery following a submaximal exercise test. Longitudinal data was analysed for 97 healthy middle-aged adults (74 male, 23 female) from 2 occasions, 12 months apart. Participants were retrospectively selected if they had stable physical activity habits, submaximal treadmill fitness and anthropometric measurements between the 2 assessment visits. A submaximal Bruce treadmill test was performed to at least 85% age-predicted maximum heart rate. Absolute heart rate and Δ heart rate recovery (change from peak exercise heart rate) were recorded for 1 and 2 min post-exercise in an immediate supine position. Heart rate recovery at both time-points was shown to be reliable with intra-class correlation coefficient values ≥ 0.714. Absolute heart rate 1-min post-exercise showed the strongest agreement between repeat tests (r = 0.867, P < 0.001). Lower coefficient of variation (≤ 10.2%) and narrower limits of agreement were found for actual heart rate values rather than Δ heart rate recovery, and for 1-min rather than 2-min post-exercise recovery time points. Log-transformed values generated better variability with acceptable coefficient of variation for all measures (2.2-10%). Overall, 1 min post-exercise heart rate recovery data had least variability over the 12-month period in apparently healthy middle-aged adults.

Postoperative radiotherapy improves survival in squamous cell carcinoma of the hypopharynx.

BACKGROUND: Postoperative radiation is considered to be "standard of care" therapy for advanced, resectable squamous cell carcinoma of the head and neck. This approach has been supported by retrospective data but has not been validated in randomized clinical trials. PATIENTS AND METHODS: The present analysis examined the clinical course of 110 patients with squamous cell cancer of the hypopharynx treated with surgery alone (n = 65) and postoperative radiotherapy alone (n = 45) between 1966 and 1990. Staging of patients was performed using the 1988 American Joint Committee on Cancer criteria. Cox regression analyses identified clinical and pathologic factors that were significant for disease-free and overall survival. Crude and adjusted cancer-specific survival rates were calculated. RESULTS: The postoperative radiotherapy group presented with more advanced disease than the surgery alone group (stage III and IV combined, 96% versus 77%, P = 0.015). Crude 5-year cancer-specific survival probabilities were 43% for the postoperative therapy group and 27% for the surgery alone group (P = NS). Adjusted 5-year survival rates, correcting for differences in significant prognostic variables between groups, were 18% and 48%, respectively, for the surgery and postoperative radiotherapy groups (P = 0.029). CONCLUSIONS: The addition of postoperative radiotherapy was associated with improved disease-free and adjusted overall cancer-specific survival in patients with advanced hypopharyngeal squamous cancer. The potential survival benefit of postoperative radiotherapy should be addressed in a randomized clinical trial.

Cystic schwannoma of the sphenoid sinus and skull base.

Skull base and intracranial cystic schwannomas are rare tumors. To our knowledge, a cystic schwannoma involving the sphenoid sinus has not been previously reported. The location and fluid-filled nature of the lesion resulted in an erroneous preliminary diagnosis of a destructive sphenoid sinus mucocele. Endoscopic biopsy and decompression established the correct diagnosis and reversed a progressive visual loss until definitive surgical removal of the lesion was accomplished. Diagnostic evaluation, histologic findings and management strategies are discussed.

Hemophilia A. Detection of molecular defects and of carriers by DNA analysis.

To understand the molecular basis of hemophilia A and to provide heterozygote detection and prenatal diagnosis by DNA analysis, we used cloned factor VIII:C DNA fragments to study 10 affected families. In four of these families, inhibitors of factor VIII:C had developed in affected persons. In one such family a deletion of approximately 80 kb within the factor VIII:C gene was identified. Carriers of the deletion were identified through detection of an abnormal DNA fragment located at the deletion end points. In another family a single nucleotide change in the coding region of the factor VIII:C gene produced a nonsense codon leading to premature termination of factor VIII:C synthesis. Carrier detection was performed in eight female members of this four-generation family. In a third family a small change in the size of a restriction-endonuclease fragment correlated with the presence of the mutant gene, and in the other seven families the molecular defect has not yet been identified. In addition, we used two common polymorphic sites in the factor VIII:C gene to differentiate the normal from the defective gene in four of six obligate female carriers from families with patients in whom inhibitors did not develop. Carrier detection was possible in other members of these families. These data suggest that DNA analysis of the factor VIII:C gene provides an accurate method of carrier detection and, potentially, of prenatal diagnosis in at least 50 per cent of the pedigrees affected by hemophilia A.