Survival after minimally invasive vs. open radical nephrectomy for stage I and II renal cell carcinoma

International Journal of Clinical Oncology - A recently reported phase III randomized trial comparing open and minimally invasive hysterectomy showed significantly higher rates of local recurrence...     

改良Duplay术和Duckett术在儿童中重度尿道下裂中的临床应用比较

目的 比较改良分期尿道板纵切卷管尿道成形术（改良Duplay术）和一期横形带蒂岛状包皮皮瓣尿道成形术（Duckett术）治疗儿童中重度尿道下裂的疗效。方法 收集81例中重度尿道下裂患儿的临床资料,根据术式不同分为改良Duplay术式组45例和Duckett术式组36例。比较2组的手术时间、出血量、住院费用、术后并发症和患儿家属对手术的满意度及治愈率。结果 与Duckett术式组比较,改良Duplay术式组的手术时间较短,尿道狭窄和尿道憩室的发生率较低（P均< 0.05）。2组的出血量、住院费用、尿瘘和龟头裂开的发生率和治愈率比较差异均无统计学意义（P均> 0.05）。Duckett术式组患儿家属对手术的满意度高于改良Duplay术式组患儿家属对一期手术的满意度（P < 0.05）,与改良Duplay术式组患儿家属对二期手术的满意度相近（P > 0.05）。结论 改良Duplay术治疗中重度尿道下裂手术时间短、尿道狭窄和尿道憩室的发生率低,其临床应用优于Duckett术。     

Video-assisted thoracoscopic bronchoplasty/pulmonary arterial angioplasty

Thoracoscopic bronchoplasty combined with pulmonary arterial angioplasty can be particularly challenging. In the past, it was often done by using a conventional incision or hybrid video-assisted small incision. In recent years, anecdotal articles have described the application of thoracoscopic bronchoplasty/pulmonary arterial angioplasty. This chapter will describe the details associated with thoracoscopic bronchoplasty/pulmonary arterial angioplasty.     

MR fingerprinting ASL: Sequence characterization and comparison with dynamic susceptibility contrast (DSC) MRI

MR Fingerprinting (MRF)‐based Arterial‐Spin‐Labeling (ASL) has the potential to measure multiple parameters such as cerebral blood flow (CBF), bolus arrival time (BAT), and tissue T₁ in a single scan. However, the previous reports have only demonstrated a proof‐of‐principle of the technique but have not examined the performance of the sequence in the context of key imaging parameters. Furthermore, there has not been a study to directly compare the technique to clinically used perfusion method of dynamic‐susceptibility‐contrast (DSC) MRI. The present report consists of two studies. In the first study (N = 8), we examined the dependence of MRF‐ASL sequence on TR time pattern. Ten different TR patterns with a range of temporal characteristics were examined by both simulations and experiments. The results revealed that there was a significance dependence of the sequence performance on TR pattern (p < 0.001), although there was not a single pattern that provided dramatically improvements. Among the TR patterns tested, a sinusoidal pattern with a period of 125 TRs provided an overall best estimation in terms of spatial consistency. These experimental observations were consistent with those of numerical simulations. In the second study (N = 8), we compared MRF‐ASL results with those of DSC MRI. It was found that MRF‐ASL and DSC MRI provided highly comparable maps of cerebral blood flow (CBF) and bolus‐arrival‐time (BAT), with spatial correlation coefficients of 0.79 and 0.91, respectively. However, in terms of quantitative values, BAT obtained with MRF‐ASL was considerably lower than that from DSC (p < 0.001), presumably because of the differences in tracer characteristics in terms of diffusible versus intravascular tracers. Test–retest assessment of MRF‐ASL MRI revealed that the spatial correlations of parametric maps were 0.997, 0.962, 0.746 and 0.863 for B₁⁺, T₁, CBF, and BAT, respectively. MRF‐ASL is a promising technique for assessing multiple perfusion parameters simultaneously without contrast agent.     

“水象”视阈下肿瘤“瘀毒互结”病机探微

[目的] 从“水象”视阈探讨肿瘤“瘀毒互结”病机,发挥中医药原创优势,为中医药治疗肿瘤提供具有中医原创特色的理论支撑。[方法] 通过象思维,从“水象”视阈,谈人体之血象于自然之水,人体经脉象于自然水系,探讨肿瘤“瘀毒”之“瘀”象于河道之“淤”,“瘀毒”之“毒”象于水体污染,并以河道淤泥堵塞及水体污染的治理方法归纳演绎出肿瘤“瘀毒互结”的治则治法。[结果] 以“水象”视阈观之,肿瘤“瘀毒互结”与河道淤堵、水体污染的发生发展过程,肿瘤治疗后机体正气的亏损与水系治理后生态环境的退化,均存在共同之“象”。水系治理的方针法则亦可类比运用于肿瘤“瘀毒”的治疗:河道之“淤”需顺水清淤,肿瘤“瘀毒”之“瘀”需化瘀通脉;水系污染需清污澄源,“瘀毒”之“毒”在解毒寻根;水系治理需重培土,“瘀毒”同治必重扶正;治水当按需制宜,治“瘀毒”应分期论治。[结论] “瘀毒互结”是肿瘤的一大核心病机,象思维是中医的原创思维,从“水象”视阈论证“瘀毒互结”病机,具有中医的原创特色。     

Calibration and validation of TRUST MRI for the estimation of cerebral blood oxygenation

Recently, a T₂‐Relaxation‐Under‐Spin‐Tagging (TRUST) MRI technique was developed to quantitatively estimate blood oxygen saturation fraction (Y) via the measurement of pure blood T₂. This technique has shown promise for normalization of fMRI signals, for the assessment of oxygen metabolism, and in studies of cognitive aging and multiple sclerosis. However, a human validation study has not been conducted. In addition, the calibration curve used to convert blood T₂ to Y has not accounted for the effects of hematocrit (Hct). In this study, we first conducted experiments on blood samples under physiologic conditions, and the Carr‐Purcell‐Meiboom‐Gill T₂ was determined for a range of Y and Hct values. The data were fitted to a two‐compartment exchange model to allow the characterization of a three‐dimensional plot that can serve to calibrate the in vivo data. Next, in a validation study in humans, we showed that arterial Y estimated using TRUST MRI was 0.837 ± 0.036 (N=7) during the inhalation of 14% O2, which was in excellent agreement with the gold‐standard Y values of 0.840 ± 0.036 based on Pulse‐Oximetry. These data suggest that the availability of this calibration plot should enhance the applicability of T₂‐Relaxation‐Under‐Spin‐Tagging MRI for noninvasive assessment of cerebral blood oxygenation. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.     

MRI assessment of cerebral oxygen metabolism in cocaine‐addicted individuals: hypoactivity and dose dependence

Long‐term cocaine use is known to negatively impact neural and cerebrovascular systems. However, the use of imaging markers to separately assess these parameters remains challenging. The primary reason is that most functional imaging markers, such as cerebral blood flow, functional connectivity, and task‐evoked functional MRI, are known to reflect a complex interplay between neural and vascular components, thus the interpretation of the results is not straightforward. The goal of the present study is to examine neural‐activity‐specific changes in cocaine addiction, using cerebral metabolic rate of oxygen (CMRO2) as a surrogate marker of aggregated neural activity. We applied a recently developed CMRO2 technique in 13 cocaine‐addicted subjects and 13 age‐ and gender‐matched control subjects, and examined the impact of long‐term cocaine use on CMRO2. Our results showed that CMRO2 in cocaine‐addicted subjects (152 ± 16 µmol/100 g/min) is significantly lower (p = 0.031) than that in controls (169 ± 20 µmol/100 g/min). Furthermore, the severity of this decreased metabolism is associated with lifetime cocaine use (p = 0.05). Additionally, the CMRO2 reduction was accompanied by a trend of decrease in cerebral blood flow (p = 0.058), but venous oxygenation was unaffected (p = 0.96), which suggested that the CMRO2 change may be attributed to a vascular deficiency in chronic cocaine users. To our knowledge, this is the first study to measure CMRO2 in cocaine‐addicted individuals. Our findings suggest that CMRO2 may be a promising approach for assessing the long‐term effects of cocaine use on the brain. Copyright © 2014 John Wiley & Sons, Ltd.     

Quantitative assessment of global cerebral metabolic rate of oxygen (CMRO2) in neonates using MRI

The cerebral metabolic rate of oxygen (CMRO₂) is the rate of oxygen consumption by the brain, and is thought to be a direct index of energy homeostasis and brain health. However, in vivo measurement of CMRO₂ is challenging, in particular for the neonatal population, in whom conventional radiotracer methods are not applicable because of safety concerns. In this study, we propose a method to quantify global CMRO₂ in neonates based on arteriovenous differences in oxygen content, and employ separate measurements of oxygenation and cerebral blood flow (CBF) parameters. Specifically, arterial and venous oxygenation levels were determined with pulse oximetry and the novel T₂ relaxation under spin tagging (TRUST) MRI, respectively. Global CBF was measured with phase contrast (PC) flow velocity MRI. The proposed method was implemented on a standard 3‐T MRI scanner without the need for any exogenous tracers, and the total scan duration was less than 5 min. We demonstrated the feasibility of this method in 12 healthy neonates within an age range of 35–42 gestational weeks. CMRO₂ values were successfully obtained from 10 neonates. It was found that the average CMRO₂ in this age range was 38.3 ± 17.7 µmol/100 g/min and was positively correlated with age (p = 0.007; slope, 5.2 µmol/100 g/min per week), although the highest CMRO₂ value in this age range was still less than half of the adult level. Test–retest studies showed a coefficient of variation of 5.8 ± 2.2% between repeated CMRO₂ measurements. In addition, given the highly variable blood flow velocity within this age range, it is recommended that the TRUST labeling thickness and position should be determined on a subject‐by‐subject basis, and an automatic algorithm was developed for this purpose. Although this method provides a global CMRO₂ measure only, the clinical significance of an energy consumption marker and the convenience of this technique may make it a useful tool in the functional assessment of the neonatal population. Copyright © 2014 John Wiley & Sons, Ltd.