[Transperineal ultrasound to measure cervical length of pregnant women in general and in particular with cervical insufficiency - a comparison of transabdominal and transperineal ultrasound as alternatives to transvaginal ultrasound]. / Der transperineale Ultraschall zur Messung der Cervixlänge bei Schwangeren im Allgemeinen und im Besonderen bei Cervixinsuffizienz - Ein Vergleich des transabdominalen und transperinealen Verfahrens als Alternativen zum transvaginalen Verfahren.

PURPOSE: To investigate the feasibility of measuring cervical length by transabdominal and transperineal ultrasound as alternatives to transvaginal ultrasound. MATERIALS AND METHODS: 33 pregnant women with and 28 without cervical insufficiency at 16 to 35 weeks of gestation were examined by an experienced examiner (DEGUM II) and the cervical length was measured twice at an interval of 6 months. Comparability, reliability and comfort of the patients during the examinations were taken for statistical analysis. RESULTS: There is poor agreement between transabdominal and transvaginal ultrasound (Lin's rho = 0.578), whereas transperineal ultrasound shows high correlation (Lin's rho = 0.922) to the measurements obtained transvaginally, a preference referring to the comfort scale and good reliability (ICC = 0.949). When regarding sub-groups (pregnant women with and without cervical insufficiency), transperineal ultrasound shows better results than transabdominal ultrasound. However, small cohort sizes affect the statistical validity. CONCLUSION: Transabdominal ultrasound cannot be recommended to measure cervical length. Besides providing exact measurements, transperineal ultrasound avoids contact between the cervix and the probe, is better accepted by patients and offers a simplified examination. This method is a good alternative to transvaginal ultrasound. Due to minor inaccuracies of the method, we recommend this technique only for patients with a cervix longer than 2.5 cm. For further analysis concerning patients with cervical insufficiency, large-scale studies should be performed.

Evaluation of established and new reference lines for the standardization of transperineal ultrasound.

OBJECTIVES: To examine the performance of a new reference line for the assessment of pelvic organ descent by transperineal ultrasound. METHODS: We compared our newly proposed reference line, between two hyperechoic contours of the symphysis pubis (Line 3), with the horizontal reference line proposed by Dietz and Wilson (Line 1) and the central pubic line proposed by Schaer et al. (Line 2). Ultrasound volumes of 94 women obtained in routine clinical practice were analyzed. The perpendicular distance from the reference lines to the internal sphincter and the most dependent part of the bladder base was measured for volumes obtained at rest, on pelvic floor muscle contraction, on Valsalva maneuver and during coughing. Measurements were repeated 4 months later by the same examiner. Rates of assessment were calculated, and intrarater reliability was evaluated using Bland-Altman plots and intraclass correlation coefficients. RESULTS: Line 2 had to be excluded from reliability analysis because of an assessment rate of only 12%, whereas Lines 1 and 3 could be assessed in 100% of volumes. The intrarater repeatability of Lines 1 and 3 was shown to be very similar. CONCLUSION: In this comparison of three potential reference lines for the assessment of pelvic organ descent by transperineal ultrasound, the central pubic line was shown to be inferior owing to poor visibility in our volumes. Inter-rater reliability analysis and validation studies are required to confirm our results.

Efficacy of magnetic thermoablation using SPIO in the treatment of osteoid osteoma in a bovine model compared to radiofrequency and microwave ablation.

PURPOSE: To evaluate heating efficacy of superparamagnetic iron oxide nanoparticles (SPIO) for electromagnetic ablation (EMA) of osteoid osteoma (OO) using an ex vivo model compared to radiofrequency ablation (RFA) and microwave ablation (MWA). METHODS: A model for OO using sliced bovine tibia and sliced muscle tissue was developed. A bone cavity filled with either a mixture of SPIO and agarose or pure agarose (control group) was established. EMA was performed using an experimental system, RFA and MWA using clinically approved systems, and the ablation protocols recommended by the vendor. For temperature measurements, fiberoptic temperature probes were inserted inside the cavity, on the outside of the periosteum, and at a 5 mm distance to the periosteum. RESULTS: Maximum temperatures with or without SPIO in the nidus were as follows: EMA: 79.9 ± 2.5/22.3 ± 0.7 °C; RFA: 95.1 ± 1.8/98.6 ± 0.9 °C; MWA: 85.1 ± 10.8/83.4 ± 9.62 °C. In RFA with or without SPIO significantly higher temperatures were achieved in the nidus compared to all other groups (p < 0.05). In MWA significantly higher temperatures were observed in the 5 mm distance to the periosteum compared to EMA and RFA with or without SPIO (p < 0.05). In MWA temperature decrease between nidus and the 5 mm distance to the periosteum was significantly lower than in RFA with or without SPIO (p < 0.0001). In MWA without SPIO temperature decrease was significantly lower than in the EMA group (p < 0.05). CONCLUSION: In the experimental setting, ablation of OO is safe and effective using EMA. It is less invasive than RFA and MWA, and it theoretically allows repeated treatments without repeated punctures. In comparison, the highest temperatures in the nidus are reached using RFA.

Molecular microarray analysis reveals allergen- and exotoxin-specific IgE repertoires in children with atopic dermatitis.

BACKGROUND: Children suffering from atopic dermatitis frequently show allergen-specific sensitization. However, the corresponding IgE-recognition patterns have not yet been extensively characterized using multiallergen microarrays. OBJECTIVE: To provide comprehensive, molecular IgE repertoires in paediatric patients with atopic dermatitis using microarray technology. METHODS: Sera of 140 affected children were screened with a protein microarray containing a panel of 95 inhalant, food and staphylococcal antigen components. In addition, total serum IgE levels and further clinical parameters were recorded. RESULTS: At a mean total IgE level of 1528 kU/L, the number of sensitizations varied from 0 to 32 per patient, and regression analysis revealed a significant association between total IgE and the quantity of recognized antigens. A total of 78 single allergen and microbial components elicited at least one IgE response, while 11 plant and 13 non-plant molecules were recognized by more than 10% of patients. Specific IgE against Staphylococcus aureus could be detected in 14% of children. Sensitization rates against the studied allergen molecules differed significantly when stratified by age. Whereas reactivity against inhalant allergens and SEC was lowest in the youngest group (<24 months) reaching highest values in children ≥ 72 months, IgE responses against food allergen components peaked in younger age groups (0-48 months) and clearly declined in patients of higher age. The large amount of microarray data could be aggregated by centroid cluster analysis revealing valid allergen clusters possibly linked with higher disease severity as determined by multivariate analysis of covariance. CONCLUSION: Allergenic molecule microarray analysis can be regarded as a suitable research tool for large-scale IgE screening in infants and children with atopic dermatitis (AD). Still, further studies in well-defined populations are needed to exactly identify its tangible benefits in the diagnostic and therapeutic management of affected patients in daily clinical practice.

Influence of selection bias on the test decision. A simulation study.

BACKGROUND: Selection bias arises in clinical trials by reason of selective assignment of patients to treatment groups. Even in randomized clinical trials with allocation concealment this phenomenon can occur if future assignments can be predicted due to knowledge of former allocations. OBJECTIVES: Considering unmasked randomized clinical trials with allocation concealment the impact of selection bias on type I error rate under permuted block randomization is investigated. We aimed to extend the existing research into this topic by including practical assumptions concerning misclassification of patient characteristics to get an estimate of type I error close to clinical routine. To establish an upper bound for the type I error rate different biasing strategies of the investigator are compared first. In addition, the aspect of patient availability is considered. METHODS: To evaluate the influence of selection bias on type I error rate under several practical situations, different block sizes, selection effects, biasing strategies and success rates of patient classification were simulated using SAS. RESULTS: Type I error rate exceeds 5 percent significance level; it reaches values up to 21 percent. More cautious biasing strategies and misclassification of patient characteristics may diminish but cannot eliminate selection bias. The number of screened patients is about three times larger than the needed number for the trial. CONCLUSIONS: Even in unmasked randomized clinical trials using permuted block randomization with allocation concealment the influence of selection bias must not be disregarded evaluating the test decision. It should be incorporated when designing and reporting a clinical trial.

Cromoglycate, reproterol, or both--what's best for exercise-induced asthma?

OBJECTIVE: International guidelines recommend short- (SABA) or long-acting b-agonists for the prevention of bronchoconstriction after exercise (EIB) in patients with exercise-induced asthma (EIA). However, other drugs are still in discussion for the prevention of EIB. We investigated the efficacy of a combination of inhaled sodium cromoglycate and the ß-mimetic drug reproterol versus inhaled reproterol alone and both versus inhaled placebo in subjects with exercise-induced asthma (EIA). METHODS: The study aimed to prove the preventive effect of a combination of 1-mg reproterol and 2-mg disodium cromoglycate (DSCG) and its single components vs. placebo, measuring the decrease of FEV1 after a standardized treadmill test in 11 patients with recorded EIA. The study medication was twice as high as those of drugs which are commercially available (e.g., Allergospasmin®, Aarane®). RESULTS: The results revealed that the combination of reproterol and DSCG was significantly effective against a decrease of FEV1 after a standardized exercise challenge test (ECT) compared to placebo. The short-acting b-agonist reproterol alone had almost the same effectiveness as the combination of reproterol and DNCG. The difference between the combination with DNCG and reproterol alone was less than 10% and insignificant (p 0.48). DNCG alone did not show a difference in the effectiveness compared to placebo. CONCLUSION: Prevention of EIA with the combination of reproterol and DSCG or with reproterol only is effective. An exclusive recommendation in favor of the combination cannot be given due to the low difference in the effectiveness versus reproterol alone. Due to the limited number of subjects and some probands showing protection under DSCG, it cannot be completely excluded that there is some preventive power of DSCG in individual cases.