Color Doppler sonographic mapping of pulmonary lesions: evidence of dual arterial supply by spectral analysis.

OBJECTIVE: Within pulmonary lesions, flow signals of pulmonary arteries can be discriminated from flow signals of central bronchial and peripheral bronchial arteries on color Doppler sonography. Our aim was to evaluate the evidence and frequency of different arterial supplies of pleural-based pulmonary lesions using qualitative and quantitative color Doppler sonography. METHODS: Forty-one patients with roentgenologically confirmed pleural-based pulmonary lesions were investigated by color Doppler sonography. The following parameters were investigated: (1) qualitative color Doppler sonographic evidence of vascularization, (2) quantitative color Doppler sonographic evidence of arterial flow signals (resistive index and pulsatility index), and (3) number of different arterial flow signals in 1 lesion by color Doppler sonographic mapping. RESULTS: We found no vascularization in 5 patients, sparse vascularization in 21, and pronounced vascularization in 15. Quantitative color Doppler sonographic parameters were as follows: mean pulmonary artery resistive index, 1.2; mean central bronchial artery resistive index, 0.5; mean peripheral bronchial artery resistive index, 0.7; mean pulmonary artery pulsatility index, 7.8; mean central bronchial artery pulsatility index, 0.7; and mean peripheral bronchial artery pulsatility index, 1.6. There was a significant difference between all types of flow signals for resistive and pulsatility index values but not between pulmonary and peripheral bronchial arteries (P = .068). In 41 patients, 57 different arterial flow signals were determined; 19 (46%) of these patients had 2 or more different arterial flow signals in a lesion. There was no significant difference between benign and malignant lesions regarding the number of flow signals. CONCLUSIONS: Evidence of at least a dual arterial supply can be found on quantitative color Doppler sonography in almost 50% of pulmonary lesions. A single spectral analysis is not suitable for characterization of the arterial supply of pulmonary lesions.     

行走和跑步两种步态模式的实验分析

目的 :分析行走和跑步运动两种模式下人体步态的特征。方法及结果 :使用自行研制的三维运动检测分析系统对 5名健康男性在跑步机上进行了不同速率下行走和跑步 2种步态模式的比较实验。结论 :行走和跑步两种步态模式的参数具有明显差异 ,步速对步态参数的影响要小于步态模式的影响。     

Intra-articular Patterns of Bucket Handle Meniscal Tears and Its Relation to Reducibility

Background

The purpose of this study was to assess the intra-articular patterns in the rotational deformities of bucket handle meniscal tears (BHMTs) based on arthroscopic findings and their clinical relevance.

Methods

From 2004 to 2009, 42 patients with a BHMT diagnosed by magnetic resonance imaging underwent arthroscopic surgery. The arthroscopic data (all procedures were recorded) were evaluated retrospectively, and BHMTs were classified according to the rotational directions of centrally displaced fragments. To assess the reliability of the agreement in this classification, 2 orthopedic surgeons re-classified BHMTs, 1 week after first trial. Intra- and interobserver reliabilities were assessed using kappa statistics. In addition, we address specific tear patterns, associated anterior cruciate ligament injury, medio-lateral difference, reducibility, chronicity, and reparability.

Results

Most of the tears could be categorized into one of 3 morphologic patterns. Of the tears, 4.8% could not be categorized. BHMTs were classified, based on the rotational directions of centrally displaced fragments, as follows; the upward rotation group (type 1), the downward rotation group (type 2) and the reverse group (type 3). The most common intra-articular pattern was type 1 (29 patients, 69%). The occurrence of the other patterns was: type 2 in 7 patients (16.7%), type 3 in 4 patients (9.5%); we were not able to make a classification of type in 2 patients (4.8%). Intra-observer reliability was 0.86 in terms of kappa statistics, which implies almost perfect agreement. Mean interobserver reliability (0.73) showed substantial agreement. Type 1 and 2 tears were easily reduced, whereas all type 3 tears (4/4) needed additional procedures to achieve reduction.

Conclusions

Based on arthroscopic findings, we describe a comprehensive BHMT classification scheme that encompasses 95.2% of all tears. Tear type was correlated with reducibility.     

Histologic Characteristics of Hepatocellular Carcinomas Showing Atypical Enhancement Patterns on 4-Phase MDCT Examination

Objective

To retrospectively define which histologic characteristics of small-sized hepatocellular carcinomas (HCCs) are related to atypical dynamic enhancement on multi-detector computed tomography (MDCT) imaging.

Materials and Methods

Seventy-three patients with 83 HCCs (3 cm or less in diameter) were included in this study. All patients underwent 4-phase MDCT imaging and subsequent surgery within eight weeks. Two independent radiologists blinded to the histologic findings retrospectively classified the HCCs as either typical (showing increased enhancement on arterial phase images followed by washout in late phase images) or atypical lesions demonstrating any other enhancement pattern. From the original pathologic reports, various histologic characteristics including gross morphology, nuclear histologic grades, presence of capsule formation, and capsule infiltration when a capsule was present, were compared among the two groups.

Results

An atypical enhancement pattern was seen in 30 (36.2%) of the 83 HCCs. The mean size of atypical HCCs (1.71 ± 0.764) was significantly smaller than that of typical HCCs (2.31 ± 0.598, p < 0.001). Atypical HCCs were frequently found to be vaguely nodular in gross morphology (n = 13, 43.3%) and to have grade I nuclear grades (n = 17, 56.7%). Capsule formation was significantly more common in typical HCCs (p < 0.001). Capsular infiltration was also more common in typical HCCs (p = 0.001).

Conclusion

HCCs showing atypical dynamic enhancement on MDCT imaging are usually smaller than typical HCCs, vaguely nodular type in gross morphology in most cases, and well-differentiated in nuclear grades, and they lack of capsule formation or capsular infiltration.     

Respiratory load compensation during mechanical ventilation—proportional assist ventilation with load-adjustable gain factors versus pressure support

Rationale In mechanically ventilated patients respiratory system impedance may vary from time to time, resulting, with pressure modalities of ventilator support, in changes in the level of assistance. Recently, implementation of a closed-loop adjustment to continuously adapt the level of assistance to changes in respiratory mechanics has been designed to operate with proportional assist ventilation (PAV+).Objectives The aim of this study was to assess, in critically ill patients, the short-term steady-state response of respiratory motor output to added mechanical respiratory load during PAV+ and during pressure support (PS).Patients and interventions In 10 patients respiratory workload was increased and the pattern of respiratory load compensation was examined during both modes of support.Measurements and results Airway and transdiaphragmatic pressures, volume and flow were measured breath by breath. Without load, both modes provided an equal support as indicated by a similar pressure–time product of the diaphragm per breath, per minute and per litre of ventilation. With load, these values were significantly lower (p < 0.05) with PAV+ than those with PS (5.1 ± 3.7 vs 6.1 ± 3.4 cmH₂O.s, 120.9 ± 77.6 vs 165.6 ± 77.5 cmH₂O.s/min, and 18.7 ± 15.1 vs 24.4 ± 16.4 cmH₂O.s/l, respectively). Contrary to PS, with PAV+ the ratio of tidal volume (V_T) to pressure–time product of the diaphragm per breath (an index of neuroventilatory coupling) remained relatively independent of load. With PAV+ the magnitude of load-induced V_T reduction and breathing frequency increase was significantly smaller than that during PS.Conclusion In critically ill patients the short-term respiratory load compensation is more efficient during proportional assist ventilation with adjustable gain factors than during pressure support.Electronic supplementary material The electronic reference of this article is . The online full-text version of this article includes electronic supplementary material. This material is available to authorised users and can be accessed by means of the ESM button beneath the abstract or in the structured full-text article. To cite or link to this article you can use the above reference.     

Food or nutrient pattern assessment using the principal component analysis applied to food questionnaires. Pitfalls,tips and tricks

We considered the Blom’s transformation, a statistical method aimed to normalise and standardise food intakes before principal component analysis. A simulation study was performed to evaluate the eigenvalue distribution of a correlation matrix under common conditions in food questionnaire analysis. The scree plot visual inspection and the Guttman–Kaiser (GK) criterion were compared to Horn’s parallel analysis to evaluate their efficacy in food pattern identification. The scree plot results as a monotone continuous series when no food patterns are present. In this situation, about 50% of the eigenvalues assume a value higher than one, showing a first fallacy of the GK. When three food patterns are simulated a clear discontinuity appears after the third eigenvalue, showing that the scree-plot visual inspection is a suitable method to identify food patterns. Finally, according to the present work it appears that the GK generates a number of false-positive food patterns.     

Deciphering phonemes from syllables in blood oxygenation level‐dependent signals in human superior temporal gyrus

Linguistic units such as phonemes and syllables are important for speech perception. How the brain encodes these units is not well understood. Many neuroimaging studies have found distinct representations of consonant–vowel syllables that shared one phoneme and differed in the other phoneme (e.g. /ba/ and /da/), but it is unclear whether this discrimination ability is due to the neural coding of phonemes or syllables. We combined functional magnetic resonance imaging with multivariate pattern analysis to explore this question. Subjects listened to nine Mandarin syllables in a consonant–vowel form. We successfully decoded phonemes from the syllables based on the blood oxygenation level‐dependent signals in the superior temporal gyrus (STG). Specifically, a classifier trained on the cortical patterns elicited by a set of syllables, which contained two phonemes, could distinguish the cortical patterns elicited by other syllables that contained the two phonemes. The results indicated that phonemes have unique representations in the STG. In addition, there was a categorical effect, i.e. the cortical patterns of consonants were similar, and so were the cortical patterns of vowels. Further analysis showed that phonemes exhibited stronger encoding specificity in the mid‐STG than in the anterior STG.     

The Role of Dietary Patterns in the Contribution of Cardiorespiratory Fitness in Community-Dwelling Older Chinese Adults in Hong Kong

ObjectiveWe examined the influence of various dietary patterns on cardiorespiratory fitness (CRF) expressed as peak oxygen uptake (VO₂peak), taking into account demographics and lifestyle risk factors.DesignProspective cohort study.Participants and methodsWe conducted multivariate linear regression analyses using available data from a cohort of community-dwelling older Chinese adults (752 men, 483 women) in Hong Kong. Baseline interviewer-administered questionnaires covered dietary intake estimation and dietary pattern generation from the food frequency questionnaire, demographic and lifestyle factors, self-reported medical history, as well as frailty status. VO₂peak at the 7-year follow-up was measured using symptom-limited maximal exercise testing on an electrically braked bicycle ergometer.ResultsIn men, baseline Diet Quality Index–International (DQI-I) score (β = 0.044, P = .013) and Okinawan diet score (β = 0.265, P = .014) was independently associated with age-adjusted VO₂peak at the 7-year follow-up. The significant association was only retained for the Okinawan diet score in the multivariate adjusted model (β = 0.227, P = .039). Dietary pattern scores including the Dietary Approaches to Stop Hypertension (DASH) score, Mediterranean-DASH Intervention for Neurodegenerative Delay Diet score, Mediterranean Diet Score, and 3 other pattern scores derived by factor analysis were not associated with VO₂peak. In women, none of the dietary pattern scores at baseline was associated with VO₂peak in both the age-adjusted and multivariate-adjusted models.Conclusions/ImplicationsA higher Okinawan diet score was associated with a higher 7-year CRF in community-dwelling Chinese older men. Further studies are warranted to examine the underlying mechanisms on how the Okinawan diet influences CRF.