Do reading processes differ in transparent versus opaque orthographies? A study of acquired dyslexia in Welsh/English bilinguals

In English, the relationship between the written and spoken forms of words is relatively opaque, leading to proposals that skilled reading requires two procedures: (a) a sublexical grapheme/phoneme conversion process allowing the correct reading of regular words (CAT) and new or pseudowords (ZAT); (b) a lexical process necessary to read irregular words accurately (TWO) and assumed to be the dominant process for familiar words. However, it has been argued that the sublexical process may be sufficient in highly transparent languages such as Welsh. If this is the case, damage to the sublexical process may lead to more severe deficits in transparent languages due to the lack of an alternative lexical process. To test this hypothesis, we compared Welsh and English oral reading and written-word recognition and comprehension in seven bilingual stroke participants with comparably impaired pseudoword reading in English and Welsh. Performance was remarkably similar across languages. Irrespective of the language tested, words were read more accurately than pseudowords. Lexical decision and word comprehension were as accurate in Welsh and in English, and when imageability effects were present they were of a similar size in both languages. This study does not support the hypothesis that orthographic transparency determines the nature of cognitive reading processes, but rather suggests that readers develop a sight vocabulary through reading experience irrespective of orthographic transparency.     

Is choroidal vascularity index a useful marker in different stages of idiopathic epiretinal membranes?

BackgroundThis study aims to evaluate the choroidal vascularity index in patients with idiopathic epiretinal membrane at different stages.MethodsThis prospective study included 125 eyes of 125 patients with idiopathic epiretinal membrane and 62 eyes of 62 healthy control subjects. In this study, epiretinal membrane stages were defined based on the spectral-domain optical coherence tomography staging system. The choroidal vascularity index was measured as the ratio of the luminal area to the stromal area in the central 1500 μm after binarization on enhanced depth imaging optical coherence tomography images. Data on epiretinal membrane stages, choroidal vascularity index, and best-corrected visual acuity were noted.ResultsOf 125 eyes with epiretinal membrane, 38 (30.4 %) had stage 1, 32 (25.6 %) had stage 2, and 55 (44 %) had stage 3 disease. Visual acuity was better in eyes with stage 1 or 2 epiretinal membrane than those with stage 3 epiretinal membrane (p < 0.001). The mean choroidal vascularity index was 2.29 ± 1.02 in the control, 2.23 ± 0.98 in the stage 1 epiretinal membrane, 2.22 ± 0.91 in the stage 2 epiretinal membrane, and 2.23 ± 1.11 in the stage 3 epiretinal membrane group. There was no significant difference between epiretinal membrane subgroups and the control group regarding the choroidal vascularity index (p = 0.81).ConclusionFrom the results obtained in the present study, the choroidal vascularity index was not effected by either the development or the progression of idiopathic epiretinal membrane.     

Comparison of Preoperative and Postoperative Ocular Biometry in Eyes with Phakic Intraocular Lens Implantations

Purpose

To compare preoperative and postoperative ocular biometry in patients with iris-fixated phakic intraocular lens (pIOLs): Artisan and Artiflex.

Materials and Methods

This study included 40 eyes with Artisan and 36 eyes with Artiflex pIOL implants. Anterior chamber depth (ACD) and axial length (AL) were measured by applanation ultrasonography (A-scan) and partial coherence interferometry (IOLMaster) preoperatively and 3 months after pIOL implantation.

Results

ACD measurements after Artisan or Artiflex pIOL implantation were smaller than preoperative measurements. Specifically, the difference after Artisan pIOL implantation was -1.07±0.17 mm by A-scan and -0.08±0.08 mm by IOLMaster. The difference after Artiflex pIOL implantation was -1.31±0.15 mm by A-scan and -0.05±0.07 mm by IOLMaster. After Artisan pIOL implantation, differences in AL measurements by A-scan were insignificant (difference: -0.03±0.15 mm), whereas postoperative AL measurements by IOLMaster were significantly longer than preoperative measurements (difference: 0.12±0.07 mm). After Artiflex pIOL implantation, AL measurements by both A-scan and IOLMaster were significantly longer than preoperative measurements (difference: 0.09±0.16 mm by A-scan and 0.07±0.10 mm by IOLMaster). In the Artiflex group, differences in AL measurements by A-scan correlated with the central thickness of the Artiflex pIOL.

Conclusion

ACD and AL measurements were influenced by iris-fixated phakic IOL implantation.     

Electrical Thalamic Stimulation in the Anterior Part of the Ventral Posterolateral Nucleus for the Treatment of Patients With Central Poststroke Pain

ObjectivesThe effects of thalamic stimulation of the anterior part of the ventral posterolateral nucleus (VPLa) for central poststroke pain (CPSP) and the pain-related electrophysiological characteristics of this structure were investigated.Materials and MethodsNine patients with CPSP manifesting as hemibody pain were enrolled. Stereotactic thalamic VPLa stimulation was implemented, and intraoperative electrophysiological studies on hyperactive and unstable discharges (HUDs) and responses to sensory and electrical stimulation were performed in the sensory thalamus. A preoperative somatosensory-evoked potential (SEP) study was carried out in all nine patients and in eight other patients with localized pain.ResultsThe patients were classified into two groups: a HUD-dominant group (group H, n = 5) and a sensory response-dominant group (group R, n = 4). HUDs were frequently encountered in the thalamic VPLa in the former group. The total number of HUDs and the number along the trajectory to the VPLa in group H were significantly larger than those in group R. The improvements on the pain numeric rating scale in group H were significantly higher than those in group R two years after surgery. The amplitude ratio of the SEP N20s in the ipsilateral to the contralateral side of CVD lesion in the study group was significantly lower than in the localized pain group.ConclusionsAdequate and stable pain relief with thalamic VPLa stimulation is obtainable in patients with CPSP who exhibit hyperactivity and electrical instability along the trajectory to this nucleus. Both responders and nonresponders were found to have severe dysfunction of the lemniscal system.     

胸椎旁神经阻滞术穿刺深度的解剖学研究

目的　观察横突、肋横突外侧韧带与脊神经之间的毗邻关系,为提高超声引导下胸椎旁神经阻滞术的安全性及阻滞效能提供解剖学依据。 方法　选用18具标本胸椎节段,取椎板外侧缘和同名脊神经根的十字交点作为测量的起点,分别测量T1~12共12个节段脊神经与横突下后缘中点、肋横突外侧韧带下缘中点之间的距离。根据“3个一组”原则,12个节段共分为4组,记为T1~3组、T4~6组、T7~9组及T10~12组,对不同组别的脊神经-横突间距、脊神经-肋横突外侧韧带间距分别进行单因素方差分析。 结果　（1）脊神经-横突间距：平均为（16.13±5.59）mm,T1~12总体呈先递增后递减的趋势,T5节段最大,为（18.88±5.78）mm,T5向上或向下节段逐渐减小,T1节段为（16.62±3.67）mm,T12节段为（9.76±3.75）mm。自上而下4组的脊神经-横突间距分别为（17.50±4.67）、（18.19±5.62）、（16.92±5.28）及（12.00±4.42）mm,T10~12组相比T1~3组（P<0.01）、T4~6组（P<0.01）、T7~9组（P<0.01）有统计学差异。（2）脊神经-肋横突外侧韧带间距：平均为（17.67±3.76）mm,自上而下4组的间距分别为（16.95±3.82）、（17.55±3.89）、（17.81±3.83）及（18.30±3.43）mm,两两比较均无统计学差异（P>0.05）。 结论　了解脊神经-横突间距、脊神经-肋横突外侧韧带间距利于估算椎旁神经阻滞的安全穿刺深度,以提高阻滞效能,避免脊神经损伤及全脊髓麻醉的风险。     

BP网络在麻醉深度监测算法上的应用

麻醉是临床手术中必不可少的环节,但麻醉的过深或过浅可能给病人带来伤害,因而对麻醉深度的监测具有较高的临床价值。脑电是目前检测麻醉深度最有潜力的方法,首先通过滤波等处理方式得到较为纯净的脑电信号,分析时域和频域的特征,计算相应的参数,并将该参数作为前向反馈神经网络的输入参数,选择合适的BP神经网络拟合得到一个能够评价麻醉深度的无量纲常数。使用BP神经网络拟合结果来表征麻醉深度准确率普遍在90%以上,反映了BP神经网络在麻醉深度监测上具有较高的应用价值。     

不同制备形态对短冠磨牙髓腔固位冠抗折性影响的研究

目的:比较3种不同预备深度和有无牙本质肩领对髓腔固位冠修复体及牙体抗折性的影响,为临床上髓腔固位冠修复短冠磨牙的牙体预备提供参考。方法:收集牙颈部至根尖形态完整的上颌离体恒磨牙30颗。设置3种髓腔预备深度3 mm、4 mm、5 mm,两种边缘预备形式,随机分为6组,通过CAD-CAM技术制作氧化锆髓腔固位冠进行修复,随后进行抗折强度测试,记录折裂负荷值以及折裂模式。结果:6组样本的折裂负荷值不管是在对接组还是肩台组中,最大载荷值均为3 mm组<4 mm组<5 mm组,但组间两两比较无显著性差异。肩台组的最大载荷值大于对接组,在3 mm和4 mm组中差异性有统计学意义。6组样本折裂模式中均以不可修复折裂为主,5 mm组中均呈现不可修复性折裂。结论:通CAD-CAM技术制作的氧化锆髓腔固位冠修复上颌短冠磨牙时,3 mm和4 mm的髓腔预备深度均能满足临床抗折强度要求,但不宜超过4 mm;另外,预备形态中引入1 mm的牙本质肩领可作为临床一种有效增加牙体和修复体抗折强度的预备方式。     

磁共振成像评估舌鳞状细胞癌浸润深度的准确性分析

目的以光镜下病理切片为参照,分析磁共振成像(magnetic resonance imaging,MRI)测量的舌鳞状细胞癌浸润深度的准确性,为临床提供参考。方法选取2018年1月至2020年9月就诊于山西医科大学第一医院口腔科和中南大学湘雅口腔医院的73例舌鳞状细胞癌患者,术前均行MRI评估舌鳞状细胞癌浸润深度,术中冰冻病理切片再次测量舌鳞状细胞癌浸润深度。结果T1加权成像测量的舌鳞状细胞癌浸润深度较病理结果平均高估1.11 mm(95%CI=0.51~1.70,t=3.72,P<0.001),相关系数r为0.95;T2加权像平均高估2.17 mm(95%CI=1.32~3.02,t=5.10,P<0.001),相关系数r为0.92。Bland?Altman图显示T1、T2加权像与病理测量的浸润深度一致性佳。结论MRI测量的舌鳞状细胞癌浸润深度较为准确,与病理测量结果相比有平均1~2 mm的高估,其中T1加权像优于T2加权像。     

病变深度对乳腺良恶性病变超声弹性成像诊断效果的影响

目的 探讨占位性病变的深度对乳腺良、恶性病变超声弹性成像诊断效果的影响.方法 选取2010年2月～2014年10月进行超声弹性成像诊断的乳腺占位患者190例,按照能否获得满意弹性图像为标准分为满意组(170例)和不满意组(20例),收集两组患者病灶位置、病灶直径大小等资料,计算不同深度病灶的超声弹性成像的灵敏度、特异度、准确度,并进行统计学分析.结果 深度≤2.0 cm的病灶获得满意弹性成像的数量明显多于＞2.0 cm的病灶,二者图像满意率差异有统计学意义(P＜0.05);直径≤2.0 cm的病灶,图像满意组人数多于图像不满意组(P＜0.05);病灶深度＜0.5 cm时,准确度和特异度最高,＞1.5 cm时灵敏度降低.结论 病灶越浅、脂肪越少、乳房层越薄,越容易得到满意的弹性图像;同等深度时,病灶直径越大,对成像越有利,病灶病变深度会影响成像的准确度、特异度、灵敏度.