Can optical diagnosis of small colon polyps be accurate? Comparing standard scope without narrow banding to high definition scope with narrow banding

AIM: To study the accuracy of using high definition(HD) scope with narrow band imaging(NBI) vs standard white light colonoscope without NBI(ST), to predict the histology of the colon polyps, particularly those < 1 cm.METHODS: A total of 147 African Americans patients who were referred to Howard University Hospital for screening or, diagnostic or follow up colonoscopy, during a 12-mo period in 2012 were prospectively recruited. Some patients had multiple polyps and total number of polyps was 179. Their colonoscopies were performed by 3 experienced endoscopists who determined the size and stated whether the polyps being removed were hyperplastic or adenomatous polyps using standard colonoscopes or high definition colonoscopes with NBI. The histopathologic diagnosis was reported by pathologists as part of routine care. RESULTS: Of participants in the study, 55(37%) were male and median(interquartile range) of age was 56(19-80). Demographic, clinical characteristics, past medical history of patients, and the data obtained by two instruments were not significantly different and two methods detected similar number of polyps. In ST scope 89% of polyps were < 1 cm vs 87% in HD scope(P = 0.7). The ST scope had a positive predictive value(PPV) and positive likelihood ratio(PLR) of 86% and 4.0 for adenoma compared to 74% and 2.6 for HD scope. There was a trend of higher sensitivity for HD scope(68%) compare to ST scope(53%) with almost the same specificity. The ST scope had a PPV and PLR of 38% and 1.8 for hyperplastic polyp(HPP) compared to 42% and 2.2 for HD scope. The sensitivity and specificity of two instruments for HPP diagnosis were similar.CONCLUSION: Our results indicated that HD scope was more sensitive in diagnosis of adenoma than ST scope. Clinical diagnosis of HPP with either scope is less accurate compared to adenoma. Colonoscopy diagnosis is not yet fully matched with pathologic diagnosis of colon polyp. However with the advancement of both imaging and training, it may be possible to increase the sensitivity and specificity of the scopes and hence save money for eliminating time and the cost of Immunohistochemistry/pathology.

Role of high definition colonoscopy in colorectal adenomatous polyp detection

AIM:To investigate the rates of polyp detection in a mixed risk population using standard definition (SDC) vs high definition colonoscopes (HDC).METHODS:This was a retrospective cohort comparative study of 3 colonoscopists who each consecutively performed 150 SDC (307,200 pixel) and 150 HDC (792,576 pixels) in a community teaching hospital.RESULTS:A total of 900 colonoscopies were evaluated (mean age 56,46.8% men),450 with each resolution.Polyps of any type were detected in 46.0% of patients using SDC and 43.3% with HDC (P=0.42).There was no significant difference between the overall number of polyps,HDC (397) and SDC (410),detected among all patients examined,(P=0.73).One or more adenomatous polyps were detected in 24.2% of patients with HDC and 24.9% of patients with SDC colonoscopy (P=0.82).There was no significant difference between HDC (M=0.41) and SDC (M=0.42) regarding adenomatous polyp (P=0.88) or advanced adenoma (P=0.56) detection rate among all patients examined.CONCLUSION:HDC did not improve yield of adenomatous polyp,advanced adenoma or overall polyp detection in a population of individuals with mixed risk for colorectal cancer.

Multicenter randomised controlled trial comparing the high definition white light endoscopy and the bright narrow band imaging for colon polyps

AIM To compare high definition white light endoscopy and bright narrow band imaging for colon polyps' detection rates. METHODS Patients were randomised to high definition white light endoscopy(HD-WLE) or the bright narrow band imaging(b NBI) during withdrawal of the colonoscope. Polyps identified in either mode were characterised using b NBI with dual focus(b NBI-DF) according to the Sano's classification. The primary outcome was to compare adenoma detection rates(ADRs) between the two arms. The secondary outcome was to assess the negative predictive value(NPV) in differentiating adenomas from hyperplastic polyps for diminutive rectosigmoid lesions.RESULTS A total of 1006 patients were randomised to HD-WLE(n = 511) or b NBI(n = 495). The mean of adenoma per patient was 1.62 and 1.84, respectively. The ADRs in b NBI and HD-WLE group were 37.4% and 39.3%, respectively. When adjusted for withdrawal time(OR = 1.19, 95%CI: 1.15-1.24, P < 0.001), the use of b NBI was associated with a reduced ADR(OR = 0.69, 95%CI: 0.52-0.92). Nine hundred and thirty three polyps(86%) in both arms were predicted with high confidence. The sensitivity(Sn), specificity(Sp), positive predictive value and NPV in differentiating adenomatous from non-adenomatous polyps of all sizes were 95.9%, 87.2%, 94.0% and 91.1% respectively. The NPV in differentiating an adenoma from hyperplastic polyp using b NBI-DF for diminutive rectal polyps was 91.0%.CONCLUSION ADRs did not differ between b NBI and HD-WLE, however HD-WLE had higher ADR after adjustment of withdrawal time. b NBI surpassed the PIVI threshold for diminutive polyps.

Improving sessile serrated adenoma detection rates with high definition colonoscopy:A retrospective study

BACKGROUND Sessile serrated adenomas(SSAs)are important premalignant lesions that are difficult to detect during colonoscopy due to poor definition,concealment by mucous caps,and flat appearance.High definition(HD)colonoscopy may uniquely aid in the detection of these inconspicuous lesions compared to standard definition(SD)colonoscopes.In the absence of existing clinical guidelines to obligate the use of HD colonoscopy for colorectal cancer screening in average-risk patients,demonstrating the benefit of HD colonoscopy on SSA detection rate(SSADR)may help strengthen the evidence to recommend its use in all settings.AIM To evaluate the benefit of HD colonoscopy compared to SD colonoscopy on SSADR in average-risk patients undergoing screening colonoscopy.METHODS Data from screening colonoscopies for patients aged 50-76 years two years before and two years after the transition from SD colonoscopy to HD colonoscopy at our large,academic teaching center were collected.Patients with symptoms of colorectal disease,positive occult blood test,history of colon polyps,cancer,polyposis syndrome,inflammatory bowel disease or family history of colon cancer or polyps were excluded.Patients whose endoscopists did not perform colonoscopies both before and after scope definition change were also excluded.Differences in individual endoscopist SSADR,average SSADR,and overall SSADR with SD colonoscopy vs HD colonoscopy were also evaluated for significance.RESULTS A total of 3657 colonoscopies met eligibility criteria with 2012 colonoscopies from the SD colonoscopy period and 1645 colonoscopies from the HD colonoscopy period from a pool of 11 endoscopists.Statistically significant improvements of 2.30%in mean SSADR and 2.53%in overall SSADR were noted with HD colonoscopy(P=0.00028 and P=0.00849,respectively).On the individual level,three endoscopists experienced statistically significant benefit with HD colonoscopy(+5.74%,P=0.0056;+4.50%,P=0.0278;+4.84%,P=0.03486).CONCLUSION Our study suggests that HD colonoscopy statistically significantly improves sessile serrated adenoma detection rate in the screening of average risk patients during screening colonoscopy.By improving the detection and removal of these lesions,adoption of HD colonoscopy may reduce the significant premalignant burden of sessile serrated adenomas.

A Reliable Adaptive High-Definition Transmission System for Distance Learning

There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great challenge for deployment. In this paper, a novel high-definition (HD) video transmission system was proposed which depends upon reliable compound multicast protocols and QoS control over the various kinds of networks. This system detects client's network condition and assigns it to a proper proxy. Each proxy is capable of detecting network parameters and adaptively tuning such transport parameters as bit rate, video resolution, frame rate and QoS mechanisms to this condition. It also provides FEC error recovery under consideration of characteristics of MPEG4 video codec. Our simulation demonstrates that different network clients such as ADSL, CERNET, and CERNET2 can receive more video reliability with less delay.

ZTE IPTV Low Bit Rate High Definition Transcoding Solution Nominated for Global IPTV Industry Award

ZTE Corporation announced on 1 March that its innovative IPTVlowbitrate highdefinition transcoding solution has been nominated for the World＇s Best Component or Enabler Award by the IPTV World Forum. The ZTE solution is on display at the Mobile World Congress 2012 （MWC 2012） in Barcelona.

Optical diagnosis of colorectal polyps using high-definition i-scan: An educational experience

AIM:To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience. METHODS:We used a digital library of HD i-scan still images, comprising twin pictures (surface enhancement and tone enhancement), collected at our university hospital. We defined endoscopic features of adenomatous and non-adenomatous polyps, according to the following parameters:color, surface pattern and vascular pattern. We familiarized the participating endoscopists on optical diagnosis of colorectal polyps using a 20-min didactic training session. All endoscopists were asked to evaluate an image set of 50 colorectal polyps with regard to polyp histology. We classified the diagnoses into high confidence (i.e., cases in which the endoscopist could assign a diagnosis with certainty) and low confidence diagnoses (i.e., cases in which the endoscopist preferred to send the polyp for formal histology). Mean sensitivity, specificity and accuracy per endoscopist/image were computed and differences between groups tested using independent-samples t tests. High vs low confidence diagnoses were compared using the pairedsamples t test. RESULTS:Eleven endoscopists without previous experience on optical diagnosis evaluated a total of 550 images (396 adenomatous, 154 non-adenomatous). Mean sensitivity, specificity and accuracy for diagnosing adenomas were 79.3%, 85.7% and 81.1%, respectively. No significant differences were found between gastroenterologists and trainees regarding performances of optical diagnosis (mean accuracy 78.0%vs 82.9%,P = 0.098). Diminutive lesions were predicted with a lower mean accuracy as compared to non-diminutive lesions (74.2% vs 93.1%, P = 0.008). A total of 446 (81.1%) diagnoses were made with high confidence. High confidence diagnoses corresponded to a significantly higher mean accuracy than low confidence diagnoses (84.0% vs 64.3%, P = 0.008). A total of 319 (58.0%) images were evaluated as having excellent quality. Considering excellent quality images in conjunction with high confidence diagnosis, overall accuracy increased to 92.8%. CONCLUSION:After a single training session, endoscopists with varying levels of experience can already provide optical diagnosis with an accuracy of 84.0%.

一种HDMI信号自动投屏器设计

机顶盒及OTT(Over The Top)设备出现以后,电视机接入信号源越来越多。用户群体中,老年人群有看电视的刚需,但由于不会操作选择正确的信号源,其面临想看电视但难以操作的困扰。对此,设计一款高清多媒体接口(High Definition Multimedia Interface,HDMI)信号投屏器,帮助不懂电视机和信号源设备操作的人群一键快速进入期望信号源的电视界面。

Prevalence of metabolic syndrome in type 2 diabetic patients: A comparative study using WHO, NCEP ATP III, IDF and Harmonized definitions

To determine the prevalence of metabolic syndrome (MetS) in Malaysian type 2 diabetic patients using WHO, NCEP ATP III, IDF and the new Harmonized definitions, and the concordance between these definitions. This study involved 313 patients diagnosed with type 2 diabetes mellitus (T2DM) at two Malaysian tertiary hospitals. Socio-demographic data were assessed using a pre-tested interviewer-administered structured questionnaire. Anthropometric measurements were carried out according to standard protocols. Clinical and laboratory characteristics were examined. Kappa (k) statistics were used for the agreement between the four MetS definitions. The overall prevalence rates of MetS (95% CI) were 95.8% (93.6-98.1), 96.1% (94.0-98.3), 84.8% (80.8-88.9) and 97.7% (96.1-99.4) according to the WHO, NCEP ATP III, IDF and the Harmonized definitions, respectively. The Kappa statistics demonstrated a slight to substantial agreement between the definitions (k = 0.179-0.875, p k = 0.875, p hest specificity (100%) in identifying MetS. In conclusion, the new Harmonized criteria established the highest prevalence of MetS among the four definitions applied. There was a very good concordance between the WHO and NCEP ATP III criteria. The extremely high prevalence of MetS observed in type 2 diabetic patients indicates an impending pandemic of CVD risk in Malaysia. Aggressive treatment of MetS components is required to reduce cardiovascular risk in T2DM.

丹参HD-ZIP基因家族的鉴定与表达分析

为筛选丹参(Salvia miltiorrhiza)中响应高温胁迫的HD-ZIP基因,利用生物信息学研究方法,对丹参全基因组的HD-ZIP基因进行了鉴定和分析,并以天丹1号为材料,通过qPCR技术检测了丹参HDZIP基因在高温胁迫下的表达模式。结果表明,丹参全基因组中包含44个HD-ZIP基因(SmHD-ZIP),不均匀地分布于8条染色体上。SmHD-ZIP可分为HD-ZIPⅠ、HD-ZIPⅡ、HD-ZIPⅢ和HD-ZIPⅣ4个亚家族,序列分析结果表明,这些蛋白质的氨基酸残基数为180~982个,相对分子质量为20.947~109.620 ku。SmHD-ZIP均为亲水蛋白,无跨膜结构域,绝大多数不含信号肽,等电点为4.48~10.91,且几乎都在细胞核表达,蛋白质稳定性较差。44个SmHD-ZIP基因中有10个基因复制事件,均为纯化选择。结构和模体分析结果表明,同一亚家族成员的外显子数目基本一致,HD-ZIPⅢ亚家族成员的外显子数目最多,模体数也最多。模体1、6是SmHD-ZIP的保守模体,模体10、11、12、13、15为HD-ZIPⅢ亚家族特有,模体5为HD-ZIPⅣ亚家族特有。通过分析高温(37℃)胁迫下SmHD-ZIP的表达模式发现,表达量升高和下降的基因数基本一致,在上调表达的基因中,SmHD-ZIP1.11、SmHD-ZIP1.13、SmHD-ZIP2.2、SmHD-ZIP2.5、SmHD-ZIP3.1、SmHD-ZIP3.4、SmHD-ZIP4.9、SmHD-ZIP4.10和SmHD-ZIP4.12的表达量提高了10倍以上,可作为提高丹参耐热性的候选基因资源。

基于OpenCV的4K HDMI相机上的自动寻边体系的研究

目前诸如HDMI显微相机等嵌入式设备主要采用肉眼观察+鼠标定位的方式选取物体边缘,存在精度差、耗时久等问题。本文提出一种基于OpenCV视觉库的实时显微图像自动寻边体系。首先,从后台采集实时图像,分离出灰度信息并保存于内存缓冲区;然后,截取鼠标点击处为中心的ROI区域,并基于直方图梯度幅度自动确定Canny边缘检测双阈值获取ROI区域边缘信息;最终,根据不同边缘类型计算鼠标点击处最近的边缘。实验结果表明:相较于肉眼观察+鼠标定位的传统边缘测量方式,本文提出的鼠标定位+自动寻边方式平均耗时缩短约36%,精度从69.86%提升至98.59%,具有精度高、效率高和延时低的特点,在显微测量等领域具有实际应用价值。

HD-tDCS及雷达认知训练游戏提升雷达操纵员绩效研究

目的比较联合或单独使用高精度经颅直流电刺激(HD-tDCS)与雷达认知训练游戏对雷达操纵员绩效提升的效果,探讨雷达操纵员更加实效的新训练方法。方法将87名被试随机分为联合组(n=23)、训练组(n=22)、刺激组(n=21)及对照组(n=21);采用HD-tDCS对现役雷达操纵员左侧背外侧前额叶持续干预9 d(1次/d,20 min/次),同步或单独进行雷达认知训练游戏;使用SPSS 26.0软件进行两因素重复测量方差分析,比较工作记忆、注意力、雷达认知训练游戏成绩及操纵员专业训练成绩的变化。结果所有成绩组别主效应均不显著;时间与组别交互效应显著的有认知能力测评2-back任务ACC成绩(P=0.02)、4-back任务RT成绩(P<0.01)、三维1-back任务ACC成绩(P=0.06边缘显著)、雷达认知训练游戏默记航线RT成绩(P<0.01)及双批航线RT成绩(P<0.01);仅时间主效应显著的有工作记忆广度任务正确最大值成绩(P<0.01)、3-back任务RT成绩(P=0.04)、注意广度任务ACC成绩(P=0.02)、精神运动警觉性任务ACC成绩(P<0.01)、默记航点ACC成绩(P<0.01)、默记航点RT成绩(P<0.01)、默记航线ACC成绩(P<0.01)、双批航线ACC成绩(P<0.01)、多批航点ACC成绩(P<0.01)、多批航点RT成绩(P<0.01)、雷达操纵员机下练习科目心算天线俯仰角成绩(P=0.04)及口报航点距离方位角成绩(P<0.01)。结论HD-tDCS及雷达认知训练游戏可以提升操纵员绩效水平,前者在安全性及实效性方面均具有较好的应用前景,后者经再优化后可直接推广使用。

HD-SDI数字视频信号处理及传输的FPGA设计与实现

设计了一种符合SMPTE292M标准的高清晰度数字电视信号采集传输用的HD-SDI卡,介绍了其电路结构,对HD-SDI中的视频数据、视频定时基准码、行号数据、校验码进行了分析,并就数字视频识别和提取模块、DMA传输模块和PLX9656局部总线到Avalon总线的转换模块进行了设计。FPGA采用Altera公司的StratixEP1S25,实验调试结果表明,HD-SDI数字视频信号处理及传输工作稳定可靠。

二维超声联合四维彩超HD-flow彩色血流显像在产前诊断先天性心脏发育异常中的应用

目的探讨二维超声联合四维彩超超高细微分辨血流技术(HD-flow)彩色血流显像在产前诊断先天性心脏发育异常中的临床应用价值。方法选取2016年7月至2018年2月在小榄人民医院行产前超声检查并分娩的单胎妊娠孕妇2 200例,先对所有入组的孕妇进行二维超声检查,二维超声检查提示胎儿疑似宫内心脏发育异常的孕妇再联合应用四维彩超HD-flow彩色血流显像进行检查。将进行二维超声的检查结果作为对照组,将二维超声+四维彩超HD-flow彩色血流显像的检查结果作为研究组,将出生后新生儿的心脏超声诊断结果或引产后胎儿心脏病理诊断结果作为金标准。观察所有入组孕妇中胎儿先天性心脏发育异常(FCHD)的检出情况,比较不同检查方式诊断FCHD胎儿的准确率。结果2 200例胎儿经随访诊断证实有56例胎儿存在先天性心脏发育异常,占所有入组胎儿总数的2.5%(56/2 200),其中,动脉弓畸形6例,三尖瓣畸形3例,完全性大动脉转位4例,右室双出口4例,单心室(房)4例,法洛四联症(TOF)8例,心内膜垫缺损4例,单纯性室间隔缺损9例、左心发育不良4例,肺动脉瓣闭锁5例,肺动脉瓣狭窄2例,永存动脉干3例;二维超声共检查出42例FCHD,有14例误诊或漏诊,准确率为75.0%,二维超声+四维彩超HD-flow彩色血流显像检查共查出52例FCHD,误诊或漏诊4例,准确率为92.8%,研究组的准确率高于对照组,差异具有统计学意义(P<0.05);研究组的灵敏度为92.1%、特异度为94.5%,对照组的灵敏度为60.7%、特异度为90.3%,研究组的灵敏度及特异度明显高于对照组,差异均有统计学意义(P<0.05)。结论二维超声联合四维彩超HD-flow彩色血流显像检查能显著提高FCHD的产前诊断准确率,具有较高的灵敏度及特异度,值得临床推广应用。

HDCT技术进展及其临床应用价值

探讨了HDCT在宝石材料探测器、影像链革新、能谱栅成像等方面的最新技术进展,详细介绍了其在超低剂量、高清图像以及冠脉成像等方面的临床应用价值,最后指出了HDCT突破了CT不断增加探测器宽度的常规发展模式,更全面地满足了临床需求。

矿山酸性废水治理HDS工艺技术研究

HDS处理工艺是一种高效底泥循环回流技术,在矿山酸性废水治理中具有提高药剂利用率、提高污泥浓度、改善污泥沉降浓缩特性等优点,在国外矿山酸性废水治理中具有广泛的应用,在国内仅有部分试验研究。通过实验室试验以及结合研究资料对HDS处理工艺在矿山酸性废水的治理过程机理进行了研究,同时对技术研究进展及应用等方面进行了现状分析。

采用HD-SDI的高清视频采集卡的设计与实现

设计了一种采用HD-SDI的高清视频采集卡,主要介绍了其电路结构,并通过上位机软件实现了数据的采集和预览,经过对该卡的实验和调试,达到了预期的效果,在此基础上可进一步研发基于FPGA的视频图像处理器。

HFHD与HD治疗在ESRD患者中的疗效及生存率比较

目的:对比分析高通量血液透析(HFHD)与血液透析(HD)在终末期肾病(ESRD)中的临床疗效及其对心脏功能、生存率的影响。方法:回顾性分析120例ESRD患者的临床资料,将患者分为观察组(HFHD治疗)和对照组(HD治疗),每组各60例。比较两组患者治疗前后的血清尿素氮(BUN)、肌酐(SCr)、β2-微球蛋白(β2-MG)和全段甲状旁腺激素(iPTH)水平、心脏功能及生存率。结果:治疗后,观察组患者的血清中BUN、SCr、iPTH和β2-MG水平低于治疗前(P<0.05);对照组患者的血清BUN、SCr水平低于治疗前(P<0.05);治疗后,观察组的血清iPTH和β2-MG水平均低于对照组,差异具有统计学意义(P<0.05)。治疗后,观察组的LVEF及E/A值高于对照组(P<0.05)。结论:HFHD治疗对ESRD患者血液内各毒素的清除能力较突出,同时可显著改善患者的心脏功能。

HD-OCT测量黄斑区神经节细胞层-内丛状层厚度对开角型青光眼诊断的意义

目的:评估利用高分辨率相干光断层扫描(Cirrus-HD OCT)测量黄斑区神经节细胞层-内丛状层(GCIPL)厚度参数对早期和中晚期青光眼的诊断意义。方法:本研究共纳入20例健康个体,26例早期青光眼患者,29例中晚期青光眼患者。对所有纳入个体均测量黄斑区GCIPL厚度参数,视盘(ONH)区参数以及视盘周围神经纤维层(RNFL)厚度参数。最后将所有数据利用SPSS 17.0统计学软件进行分析,分别计算各参数诊断早期和中晚期青光眼的AUC值,以比较和评价各参数的诊断意义。结果:对于早期青光眼组,AUC值最高的为RNFL平均值(0.871)和7∶00位值(0.896),GCIPL各参数也表现出较高的AUC值,其中GCIPL平均值和最小值相应的AUC值分别为0.847和0.812。对于中晚期青光眼组,AUC值最高为盘沿面积(0.992),其次为RNFL平均值(0.991),而GCIPL各参数中平均值与最小值的AUC值分别为0.967和0.983。对于早期青光眼诊断,灵敏度最高的指标为RNFL平均值(76.9%),而特异度最高的指标为GCIPL平均值(93.5%)。结论:GCIPL作为诊断青光眼的新指标在诊断早期和中晚期青光眼时,具有与RNFL相似的诊断意义。对于早期青光眼,诊断时应重点观察RNFL平均值,而在筛查时应重点观察GCIPL的平均值。