Group consensus review minimizes the diagnosis of "follicular lesion of undetermined significance" and improves cytohistologic concordance

We conducted a group consensus review of thyroid aspirates that were previously interpreted as “atypia of undetermined significance/follicular lesion of undetermined significance” (AUS/FLUS) and followed by surgical interventions. The study aimed to investigate if consensus review would minimize the diagnosis of AUS/FLUS with an optimal interobserver agreement and also promote a better cytohistologic concordance. A group of reviewers who were blinded to the corresponding histologic findings simultaneously evaluated a total of 50 aspirates at a multiheaded light microscope. Using the Bethesda System for Reporting Thyroid Cytopathology as a guideline, a consensus interpretation was reached upon review of each aspirate. Interobserver agreement was calculated and recorded. The cytohistologic correlation was then performed between the consensus interpretation and the corresponding histologic diagnosis. The consensus review reclassified 26 (52%) aspirates as non‐neoplasia/benign, 10 (20%) as follicular neoplasm/suspicious for a follicular neoplasm, 1 (2%) as papillary thyroid carcinoma, and 2 (4%) as nondiagnostic. Eleven (22%) aspirates remained AUS/FLUS. The interobserver agreement across the five diagnostic categories ranged from 71.6% to 100% with an average level of 88.8%. Cytohistologic concordance was achieved in 24 of 26 (92.3%) and 9 of 11 (81.8%) aspirates that were reclassified as non‐neoplasia/benign and neoplasia/malignancy, respectively. A diagnostic accuracy of 89.2% (33/37) was obtained in reclassified cases. In conclusion, the group consensus review minimized AUS/FLUS, offered an optimal level of interobserver agreement, and most importantly, promoted excellent cytohistologic concordance in reclassified cases and, therefore, could play a substantial role in the future in reducing reaspiration and/or unnecessary surgeries. Diagn. Cytopathol. 2012. © 2011 Wiley‐Liss, Inc     

High-resolution ZTE imaging of human teeth

MRI with zero echo time (ZTE) is achieved by 3D radial centre‐out encoding and hard‐pulse RF excitation while the projection gradient is already on. Targeting short‐T₂ samples, the efficient, robust and silent ZTE approach was implemented for high‐bandwidth high‐resolution imaging requiring particularly rapid transmit‐receive switching and algebraic image reconstruction. The ZTE technique was applied to image extracted human teeth at 11.7T field strength, yielding detailed depictions with very good delineation of the mineralised dentine and enamel layers. ZTE results are compared with UTE (ultra‐short echo time) MRI and micro‐computed tomography (μCT), revealing significant differences in SNR and CNR yields. Compared to μCT, ZTE MRI appears to be less susceptible to artefacts caused by dental fillings and to offer superior sensitivity for the detection of early demineralisation and caries lesions. Copyright © 2012 John Wiley & Sons, Ltd.     

Timing of maturation and predictors of Tanner stage transitions in boys enrolled in a contemporary British cohort

This study describes the timing of puberty in 8- to 14-year-old boys enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) and identifies factors associated with earlier achievement of advanced pubic hair stages. Women were enrolled during pregnancy and their offspring were followed prospectively. We analysed self-reported pubic hair Tanner staging collected annually. We used survival models to estimate median age of attainment of pubic hair stage >1, stage >2 and stage >3 of pubic hair development. We also constructed multivariable logistic regression models to identify factors associated with earlier achievement of pubic hair stages. Approximately 5% of the boys reported Tanner pubic hair stage >1 at age 8; 99% of boys were at stage >1 by age 14. The estimated median ages of entry into stages of pubic hair development were 11.4 years [95% confidence interval (CI) 11.3, 11.4] for stage >1, 12.7 years [95% CI 12.7, 12.8] for stage >2 and 13.5 years [95% CI 13.5, 13.6] for stage >3. Predictors of younger age at Tanner stage >1 included low birthweight, younger maternal age at delivery and being taller at age 8. Associations were found between younger age at attainment of stage >2 and gestational diabetes and taller or heavier body size at age 8. Being taller or heavier at age 8 also predicted younger age at Tanner stage >3. The results give added support to the strong influence of pre-adolescent body size on male pubertal development; the tallest and heaviest boys at 8 years achieved each stage earlier and the shortest boys later. Age at attainment of pubic hair Tanner stages in the ALSPAC cohort are similar to ages reported in other European studies that were conducted during overlapping time periods. This cohort will continue to be followed for maturational information until age 17.     

Vaporized perfluorocarbon improves oxygenation and pulmonary function in an ovine model of acute respiratory distress syndrome.

BACKGROUND: Perfluorocarbon liquids are being used experimentally and in clinical trials for the treatment of acute lung injury. Their resemblance to inhaled anesthetic agents suggests the possibility of application by vaporization. The authors' aim was to develop the technical means for perfluorocarbon vaporization and to investigate its effects on gas exchange and lung function in an ovine model of oleic acid-induced lung injury. METHODS: Two vaporizers were calibrated for perfluorohexane and connected sequentially in the inspiratory limb of a conventional anesthetic machine. Twenty sheep were ventilated in a volume controlled mode at an inspired oxygen fraction of 1.0. Lung injury was induced by intravenous injection of 0.1 ml oleic acid per kilogram body weight. Ten sheep were treated with vaporized perfluorohexane for 30 min and followed for 2 h; 10 sheep served as controls. Measurements of blood gases and respiratory and hemodynamic parameters were obtained at regular intervals. RESULTS: Vaporization of perfluorohexane significantly increased arterial oxygen tension 30 min after the end of treatment (P < 0.01). At 2 h after treatment the oxygen tension was 376+/-182 mmHg (mean +/- SD). Peak inspiratory pressures (P < 0.01) and compliance (P < 0.01) were significantly reduced from the end of the treatment interval onward. CONCLUSION: Vaporization is a new application technique for perfluorocarbon that significantly improved oxygenation and pulmonary function in oleic acid-induced lung injury.     

Periodic leg movements in patients with obstructive sleep apnea syndrome during nCPAP therapy

Summary Excessive daytime sleepiness and concentration deficits are complained by patients with obstructive sleep apnea syndrome (OSAS) as well as by patients with periodic leg movements (PLM). PLM observed during nCPAP (nasal continuous airways pressure) therapy may therefore cause persistent complaints of diurnal symptoms despite sufficient treatment. 65 OSAS-patients (58 men, 7 women, aged 55.6 ± 8.0 years) were investigated before starting and after the first two nights of nCPAP therapy. Apnea/Hypopnea index decreased in all patients (28.8 ± 18.4/h to 11.5 ± 13.0/h, p ≤ 0.01). 26 patients had an initial PLM index > 5/­h which decreased during treatment (14.6 ± 6.4/h to 10.7 ± 7.8/h) with significant increase of sleep stages 3 and 4. In 22 patients with PLM index < 5/h index increased during therapy (2.7 ± 1.2 to 5.6 ± 7.7/h, p ≤ 0.01). 17 patients developed PLM for the first time during nCPAP-therapy (10.9 ± 3.2 PLM/h). Optimizing of nCPAP therapy did not change PLM frequency. Though the pathogenesis and daytime consequences of PLM in OSAS are not fully proved yet our study may entail different therapeutic approaches. In patients with a decrease of PLM during CPAP-therapy movements seemed at least partially induced by OSAS and CPAP may be the sufficient treatment. In the majority of our cases PLM was demasked during nCPAP therapy thus indicating an independent coexistence of periodic limb movement disorder and OSAS. These patients may profit from a treatment similar to the one in restless legs syndrome when daytime symptoms persist during CPAP therapy.     

Body plethysmography--its principles and clinical use

Body plethysmography allows to assess functional residual capacity (FRC(pleth)) and specific airway resistance (sRaw) as primary measures. In combination with deep expirations and inspirations, total lung capacity (TLC) and residual volume (RV) can be determined. Airway resistance (Raw) is calculated as the ratio of sRaw to FRC(pleth). Raw is a measure of airway obstruction and indicates the alveolar pressure needed to establish a flow rate of 1 L s(-1). In contrast, sRaw can be interpreted as the work to be performed by volume displacement to establish this flow rate. These measures represent different functional aspects and should both be considered. The measurement relies on the fact that generation of airflow needs generation of pressure. Pressure generation means that a mass of air is compressed or decompressed relative to its equilibrium volume. This difference is called "shift volume". As the body box is sealed and has rigid walls, its free volume experiences the same, mirror image-like shift volume as the lung. This shift volume can be measured via the variation of box pressure. The relationship between shift volume and alveolar pressure is assessed in a shutter maneuver, by identifying mouth and alveolar pressure under zero-flow conditions. These variables are combined to obtain FRC(pleth), sRaw and Raw. This presentation aims at providing the reader with a thorough and precise but non-technical understanding of the working principle of body plethysmography. It also aims at showing that this method yields significant additional information compared to spirometry and even bears a potential for further development.