Synthetic MRI is not yet ready for morphologic and functional assessment of patellar cartilage at 1.5 Tesla

PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences.     

术中目标导向液体治疗在腹膜后巨大恶性肿瘤切除术患儿中的应用

目的:探讨基于脉压变异度（PPV）的目标导向液体治疗（GDFT）在腹膜后巨大恶性肿瘤切除术患儿中的应用。方法:择期行腹膜后巨大恶性肿瘤切除术患儿64例，年龄0.5~3岁，ASA Ⅱ-Ⅲ级。随机将患儿分为目标导向液体治疗组（G组）和常规液体治疗组（C组），每组32例。G组以PPV为指导，根据GDFT方案进行液体管理，C组采用常规液体管理。记录手术开始（T1）、手术开始后1 h（T2）、手术结束（T3）的MAP、CVP、PPV、Lac值、TNF-α、IL-6浓度。记录术中输注晶体液量、胶体液量、液体总量、出血量、尿量、手术时间、多巴胺使用率以及排气时间、术后住院时间和恶心呕吐发生率。结果:G组输注晶体液量显著少于C组（P＜0.05），而输注胶体液量显著多于C组（P＜0.05）。两组术中输注液体总量、出血量、尿量与多巴胺使用率方面差异无统计学意义。T2、T3时刻，G组PPV、TNF-α、IL-6显著低于C组（P＜0.05），而两组间MAP、CVP、Lac在各时点差异无统计学意义。G组术后排气时间明显短于C组（P＜0.05），而在术后恶心呕吐发生率和住院时间方面两组差异无统计学意义。结论:PPV指导的GDFT可以应用于腹膜后巨大恶性肿瘤切除术患儿，能维持其血流动力学稳定，减少炎症因子IL-6、TNF-α释放，促进胃肠功能恢复，但对术后转归无明显影响。     

Motor dysfunction in mild cognitive impairment as tested by kinematic analysis and transcranial magnetic stimulation

ObjectivePrevious studies have demonstrated voluntary movement alterations as well as motor cortex excitability and plasticity changes in patients with mild cognitive impairment (MCI). To investigate the pathophysiology of movement abnormalities in MCI, we tested possible relationships between movement abnormalities and primary motor cortex alterations in patients.MethodsFourteen amnestic MCI (aMCI) patients and 16 healthy controls were studied. Cognitive assessment was performed using clinical scales. Finger tapping was recorded by a motion analysis system. Transcranial magnetic stimulation was used to test the input/output curve of motor evoked potentials, intracortical inhibition, and short-latency afferent inhibition. Primary motor cortex plasticity was probed by theta burst stimulation. We investigated correlations between movement abnormalities, clinical scores, and cortical neurophysiological parameters.ResultsMCI patients showed less rhythmic movement but no other movement abnormalities. Cortical excitability measures were normal in patients, whereas plasticity was reduced. Movement rhythm abnormalities correlated with frontal dysfunction scores.ConclusionOur study in MCI patients demonstrated abnormal voluntary movement and plasticity changes, with no correlation between the two. Altered rhythm correlated with frontal dysfunction.SignificanceOur results contribute to the understanding of pathophysiological mechanisms of motor impairment in MCI.     

基因组拷贝数变异测序与染色体核型分析在胎儿遗传学诊断中的比较

目的比较基因组拷贝数变异测序(CNV-seq)技术和染色体核型分析和在产前胎儿遗传学诊断中的应用价值。方法收集来我院有产前诊断指征进行羊水穿刺的259例孕妇,取材后,送检染色体核型分析和CNV-seq,比较两种方法在产前诊断中的优缺点。结果259例标本中,共诊断异常染色体核型及微缺失微重复23例,总阳性诊断率8.88%(23/259),CNV-seq结果显示,共有22例染色体拷贝数异常(12例三体+9例微缺失微重复+1例三倍体),检出率为8.49%;染色体核型分析结果显示为:17例染色体异常(12例三体+3例结构异常+1例嵌合型+1例三倍体),检出率为6.56%。此外还检出染色体多态7例。结论CNV-seq与染色体核型分析对于染色体非整倍体的检测效力一致,CNV-seq能检测染色体微缺失微重复,染色体核型分析则能诊断出三体具体核型,在怀疑性染色体异常时,建议行两者联合检测。     

Patterns of body weight change affect weight loss during a multidisciplinary intervention in adolescents with obesity

AimThe current pediatric obesity health challenge necessitates a better understanding of the factors affecting weight loss success during interventions. The aim of this observational study was to test the impact of the rate of initial weight loss and body weight variability on weight loss during a 9-month residential, multidisciplinary weight loss program in adolescents with obesity.MethodsThis retrospective study considered a whole sample of 510 adolescents with obesity (12–16 years, 435 girls). Body weight assessment was performed before (T0) and each week during the 9 months of a multidisciplinary weight loss program. Initial weight change (week 4-W4) and overall weight change at week 12 (T1) and the end of the intervention (T2) were considered. Participants were divided into three groups (tertiles), based on their percentage of weight loss between T0 and W4; and weight variability was expressed by the root mean square error (RMSE) around each participant’s regression line at each considered period (W4, T1, T2).ResultsAdolescents with lower initial weight loss at W4 (tertile 3) displayed the lesser weight loss at T1 and T2 compared with adolescents in tertile 1 and 2. The RMSE was positively associated with the percentage of weight loss of the period considered, but when the analyses were adjusted for age and initial body weight, there was no more significant association.ConclusionsThe rate of weight loss during the first few weeks is crucial for weight loss success, and weight variability is positively associated with weight loss in adolescents with obesity. Overall, results show that initial body weight is a determinant characteristic to consider during a lifestyle intervention. Further studies are thus needed to better understand the relationship between body weight change patterns and weight loss during the dynamic state that is adolescence.     

The patellar ligament: A comprehensive review

The patellar ligament (PL) is an epiphyseal ligament and is part of the extensor complex of the knee. The ligament has gained attention due to its clinical relevance to autograft and tendinopathy. A variety of anatomical variations of the PL such as aplasia, numerical variations, and vascularity are being reported recently by clinicians and anatomists. The aim of this literature was to review the available literature to provide a consensus regarding anatomic variations of the PL, neurovasculature surrounding the PL, histology of the PL, and various aspects of PL measurements with relevance to the surgical considerations and sex and age-related differences. A narrative review of the patellar ligament was performed by conducting a detailed literature search and review of relevant articles. A total of 90 articles on the patellar ligament were included and were categorized into studies based on anatomical variations, neurovasculature, morphometrics, microanatomy, sex and age-related difference, and ACL reconstruction. The anatomical variations and morphometrics of the PL were found to correlate with the frequency of strain injuries, tendinopathy, and efficacy of the PL autograft in anterior cruciate ligament reconstruction. The sex differences in PL measurements and the effect of estrogen on collagen synthesis explained a higher incidence of patellar tendinopathy in women. An awareness of its variations enables careful selection of surgical incisions, thereby avoiding complications related to nerve injury. Accurate knowledge of the PL microanatomy assists in understanding the mechanism of ligament degeneration, rupture, autograft harvesting, and ligamentization results.     

Extracts of different pollen species and their effect on human tear fluid and an epithelial cell line

Purpose: Hazelnut and birch pollen are known to destroy tear film components and attack ocular surface cells. We investigated further pollen species from different plant families, whether they show similar effects on human tear fluid and an epithelial cell line in vitro, to provide a broad basis for further research on pollen reactions affecting the tear film and ocular surface.

Materials and methods: Regional pollen species from different plant families (Adoxaceae, Betulaceae, Fagaceae, Juglandaceae, Malvaceae, Oleaceae, Pinaceae, Plantaginaceae, Poaceae, Salicaceae, Sapindaceae) were collected. Their proteolytic activity was evaluated by Zymography. Human tear fluid and cells of an epithelial cell line were incubated with pollen extracts. Tear fluid was analyzed by Polyacrylamide gel electrophoresis (PAGE). Cytomorphology was assessed microscopically and cell viability by proliferation (MTS), water-soluble tetrazolium (WST-1) assay and the impedance-based xCELLigence real-time analysis (RTCA).

Results: Zymography revealed significant protease activity and PAGE showed the degradation of tear proteins by different pollen species. Cells incubated with pollen extracts presented dose- and time-dependent cytomorphological changes. MTS, WST-1, and RTCA revealed cytostatic as well as cytotoxic effects of pollen extracts.

Conclusions: Pollen species from different plant families exert proteolytic activity and degrade human tear fluid as well as epithelial cells, which may play a crucial role in the pathogenesis of allergic and non-allergic reactions affecting the ocular surface.     

Radiologists’ Self-Assessment Versus Peer Assessment of Perceived Probability of Recommending Additional Imaging

ObjectiveDetermine radiologist ability to accurately select the probability of recommendation of additional imaging (RAI) for themselves and colleagues when arrayed in a feedback report.MethodsIn this institutional review board–approved study, we analyzed 318,366 diagnostic imaging reports from examinations performed in the radiology department of a large quaternary teaching hospital during calendar year 2016. A validated machine learning algorithm identified reports containing RAI. A multivariable logistic regression model was then used to determine the probability of RAI. In 2018, an e-mailed survey asked radiologists to identify their own RAI probability and that of their colleagues from a report arrayed lowest to highest. Radiologists were grouped into quartiles based on their RAI probability. χ² Analysis compared self-assessment and assessment of colleagues between quartiles.ResultsForty-eight of 57 radiologists completed the survey (84.2%). Fourteen (29.2%) accurately self-identified their RAI probability (chose the correct quartile); 34 (70.8%) did not. There was no statistically significant difference between quartiles of radiologists and their ability to self-identify their RAI probability (ie, radiologists in the bottom or top quartile of RAI probabilities did not correctly predict their RAI probability). However, radiologists were better able to identify the RAI probability of their colleagues who were in the top and bottom quartiles.DiscussionRadiologists were unable to estimate their own RAI probability but were better at predicting the RAI probability of colleagues. Given that radiologists, and physicians in general, may be poor evaluators of their own performance, objective assessment tools are likely needed to help reduce unwarranted variation.