Test‐retest reliability of the default mode network in a multi‐centric fMRI study of healthy elderly: Effects of data‐driven physiological noise correction techniques

Understanding how to reduce the influence of physiological noise in resting state fMRI data is important for the interpretation of functional brain connectivity. Limited data is currently available to assess the performance of physiological noise correction techniques, in particular when evaluating longitudinal changes in the default mode network (DMN) of healthy elderly participants. In this 3T harmonized multisite fMRI study, we investigated how different retrospective physiological noise correction (rPNC) methods influence the within‐site test‐retest reliability and the across‐site reproducibility consistency of DMN‐derived measurements across 13 MRI sites. Elderly participants were scanned twice at least a week apart (five participants per site). The rPNC methods were: none (NPC), Tissue‐based regression, PESTICA and FSL‐FIX. The DMN at the single subject level was robustly identified using ICA methods in all rPNC conditions. The methods significantly affected the mean z‐scores and, albeit less markedly, the cluster‐size in the DMN; in particular, FSL‐FIX tended to increase the DMN z‐scores compared to others. Within‐site test‐retest reliability was consistent across sites, with no differences across rPNC methods. The absolute percent errors were in the range of 5–11% for DMN z‐scores and cluster‐size reliability. DMN pattern overlap was in the range 60–65%. In particular, no rPNC method showed a significant reliability improvement relative to NPC. However, FSL‐FIX and Tissue‐based physiological correction methods showed both similar and significant improvements of reproducibility consistency across the consortium (ICC = 0.67) for the DMN z‐scores relative to NPC. Overall these findings support the use of rPNC methods like tissue‐based or FSL‐FIX to characterize multisite longitudinal changes of intrinsic functional connectivity. Hum Brain Mapp 37:2114–2132, 2016. © 2016 Wiley Periodicals, Inc.     

Describing the mandible in patients with craniofacial microsomia based on principal component analysis and thin plate spline video analysis

Craniofacial microsomia (CFM) is most often described as a unilateral malformation of derivatives of the first and second branchial arches. The mandible has been classified using several classification systems. However, all are based on two-dimensional imaging. The aim of this study was to mathematically describe the deformed mandible based on principal component analysis (PCA) in a three-dimensional way. This may aid in defining the flaws in existing surgical corrections of the mandible through the identification of the differences in shape compared with a normal mandible in a holistic view with the help of videos. Forty-three homologous landmarks were defined to describe a mandible with CFM. Computed tomography scans of 22 patients and 30 controls were marked manually. The changes in shape between the mandibles were visualized using videos. A lateral rotation with increase in posterior rotation of the condyle due to shortening of the condyle–gonial height and a longitudinal rotation with outward bending of the mandibular angle were noted on the affected side, as well as an inward bending of the angle on the unaffected side. Due to the compensatory remodelling of the mandible on the unaffected side, one could suggest that CFM is never truly unilateral.     

Using three-dimensional nasal forms to compare definitive unilateral cleft lip nose correction with/without a cross-lap joint cartilage graft technique

To compare three-dimensional (3D) nasal forms after definitive correction of unilateral cleft lip (UCL)-nose using an extended spreader cartilage graft with/without a cross-lap joint cartilage graft technique.Twenty-four patients with UCL who underwent definitive nose correction using an extended spreader cartilage graft with a cross-lap joint technique (CLJ group) and fifteen patients with UCL who underwent nose correction without a cross-lap joint technique (non-CLJ group) were enrolled in this study. Pre- and postoperative 3D nasal forms were compared between the two groups.The CLJ group demonstrated more successful recovery of the nasal tip and anterior nasal ridge in the center of the face (P < 0.01), and the higher nasal tip was maintained for more than 1 year (P = 0.008). The differences in the cephalo-caudal heights of the nasal alar groove and curvatures of the alar groove arch were successfully improved in both CLJ and non-CLJ groups. The nasal angles on lateral profiles did not change in either group.An extended spreader cartilage graft with a cross-lap joint technique facilitates satisfactory recovery of the nasal tip in the center of the face and a higher nasal tip, avoiding over-projection in the definitive correction of UCL-nose.     

法洛氏四联症矫治术后中远期肺动脉高压

【】目的 报道一组法洛氏四联症矫治术后中远期肺动脉压力及阻力升高的病例。方法2009.01-2011.04间我院行法洛氏四联症矫治术共181例(我院181例接受法洛氏四联症矫治术患儿),随访2-5年怀疑患出现肺动脉高压者并对其行右心导管检查最终确诊19例,分析单纯TOF矫治术后产生肺动脉高压的因素。结果19例患者在随访的2-5年内,绝大多数没有未出现明显临床症状。WHO心功能评定I/II级17例,III/IV级2例。问卷调查Borg呼吸困难评分为1-7分,中位数为4分。BNP检查为(11-＞300000)pg/ml,BNP的中位数为266pg/ml。右心导管检查示不同程度的肺动脉压力和阻力上升升高,其中轻度肺动脉高压16例,占绝大多数,所有患者肺小动脉楔入压均正常(6-10mmHg),肺动脉-右心室连续测压压力阶差小于10mmHg,右房压力属正常范围(6-11mmHg)。部分患者同时行肺小动脉造影,没有发现肺动脉高压特征性改变。无急性肺血管扩张试验阳性者。讨论部分法洛氏四联症矫治术后患者中远期会出现肺动脉高压及全肺阻力升高,其机制目前并不十分确定清楚,可能是一个多因素交叉的复杂过程。     

Lower limb deformity assessment and correction

This paper draws on the work of Dror Paley et al and describes the basic principles of clinical and radiographic assessment of coronal plane lower limb deformity. It covers concepts of mechanical axis deviation and of the Centre of Rotation of Angulation (CORA) which influence the choice of corrective osteotomy shape and its location.     

鼻内镜下二线减张鼻中隔矫正术43例临床分析

探讨鼻内镜下鼻中隔二线减张法治疗鼻中隔偏曲的疗效。