Notes on the use of low magnification telescopes in low vision care

Several areas related to the use of telescopes in low vision are reviewed. These include: contrast sensitivity function; eccentric viewing through a telescope; field of view; telescope used in reverse; and IOL-spectacle lens telescopic systems. Experimental data are included to support selected clinical observations routinely made by low vision clinicians.     

眼动脉彩色多普勒血流频谱检测在甲亢诊断中的应用

采用ＣＤＦＩ对３４例初诊甲亢患者的眼动脉进行检测，３４例患者根据Ｔ３结果分为两组，同时１０位患者治疗前后的眼动脉血流速度对照。结果表明，甲亢患者的眼动脉血流速度高于正常人，但与Ｔ３值无相关。１０例患者的眼动脉血流速度随着Ｔ３、Ｔ４下降而恢复正常。结论：ＣＤＦＩ测定眼动脉血流频谱可用于甲亢的诊断和治疗观察。     

1977～1990年同济医科大学新生视力状况分析

用统计学方法对14年来（1977～1990年）我校6746名新生（13492只眼）的视力状况进行分析。结果表明；新生正常视力逐年减少，视力不良率相应上升（P＜0.001）。城市学生的视力比农村学生差，男生的视力优于女生（P＜0.001）。17～19岁组的视力明显低于其他年龄组（P＜0.001）。高考分数线升高与正常视力者减少呈明显负相关；而与视力不良者增加呈正相关（P＜0.001,＜0.05）。本文认为近距离用眼持续时间过长及环境视域小等是引起视力不良的主要原因。     

超声诊断甲状腺腺瘤与单发结节性甲状腺肿的价值

目的　探讨超声在甲状腺腺瘤与单发结节性甲状腺肿鉴别诊断中的价值。方法　对两种疾病的二维及彩色多普勒声像图进行分析并比较。结果　甲状腺腺瘤与单发结节性甲状腺肿比较 ,甲状腺大小、结节大小、结节内回声及周围回声组间差异均无统计学意义 (P >0 .0 5 ) ;结节边缘晕环及结节内部和周边血流信号差异有显著性 (P <0 .0 5 )。结论　单发结节性甲状腺肿易误诊为腺瘤 ,结节边缘晕环及结节内部和周边血流信号对鉴别诊断可提供帮助     

正常人肺静脉管径及其血流频谱的研究

肺静脉血流和肺静脉管径的变化与左房压力及左心室舒张功能密切相关 [1 ,4 ] 。超声心动图可以直接、动态观察肺静脉内径及血流频谱变化 ,但是目前超声尚无健康人肺静脉内径正常值。我们应用彩色超声多普勒技术对正常人及孕周 2 4周以上的妊娠妇女进行肺静脉内径及血流频谱研究 ,以探索正常人肺静脉的显示率、内径正常值、血流频谱特点。观察高动力状态及呼吸对肺静脉管径和血流频谱的影响。1　材料与方法1.1　研究对象　 16 9例排除心肺疾患的健康人分组进行研究。其中成年男性组 4 4例、成年女性组 4 6例、儿童组 14例、中期妊娠组 (中妊 …     

The effect of laser refractive surgery on the on-field performance of professional baseball players.

BACKGROUND: The aim of this study was to determine the effect of laser refractive surgery on the offensive performance of professional baseball players. METHODS: Extensive search of the public media was conducted to determine which major league baseball players had undergone laser refractive surgery and when the procedure was performed. Baseball performance data were then used to determine presurgery and postsurgery baseball performance averages. A total of 17 position players were identified; however, 5 of these players were not considered in the analysis owing to insufficient playing experience either before or after the laser procedure. RESULTS: No statistically significant or practically significant difference was found between the presurgery and postsurgery means on either on-base percentage (P = 0.31), batting average (P = 0.39), slugging percentage (P = 0.66) or on-base plus slugging (OPS; P = 0.997) of major league baseball players. CONCLUSIONS: These preliminary findings suggest that professional baseball players should not expect a laser refractive surgical procedure to significantly improve their offensive baseball performance, despite the elimination of glasses or contact lens wear.     

Local circuit neurons of macaque monkey striate cortex: I. Neurons of laminae 4C and 5A

A study has been made, using Golgi preparations, of the organization of neurons with smooth or sparsely spined dendrites, here called local circuit neurons, of the macaque monkey primary visual cortex. Since these neurons include those responsible for inhibitory circuitry of the cortex, a better understanding of their anatomical organization is essential to concepts of functional organization of the region. This account describes those neurons found with cell body and major dendritic spread within the thalamic recipient zone of lamina 4C and its border zone with lamina 5A. The neurons are grouped firstly in terms of in which laminar division the soma occurred--4C beta, 4C alpha or the border zone of 5A-4C beta--and secondly, into varieties on the basis of the interlaminar projection patterns of their axons. Most, if not all, of the local circuit neurons of these divisions have interlaminar axon projections as well as an arbor local to their cell body and dendritic field. These interlaminar projections are highly specific, targeting from one to five laminar divisions depending on the variety of neuron; on this basis 17 varieties of local circuit neuron are described. While the number of varieties appears dauntingly large in terms of understanding the functional circuitry of the region, the clear-cut organization of the interlaminar links may provide clues as to the information processing that concerns each neuron. The local circuit neuron axon projections can be related to a wealth of information already available concerning the laminar organization of afferent axons and efferent cell groups, the organization of spiny neuron intrinsic relays (presumed to be excitatory), and physiological properties of different laminar divisions. It is hoped that the information derived from this study can serve as a guide for correlated physiological-anatomical studies on single cells of the region.     

视觉近点测定修布和验布作业视疲劳的初步探讨

应用视觉近点测定评价纺织厂不同作业工人的视疲劳。检查了32名修布工人和38名验布工人。同一工厂的33名保育员作对照组。结果表明:视觉近点的测定指标比调查受试者主诉的眼视觉症状更为敏感。修布和验布组在工作后,作业者的视觉近点比上班前明显变远,但时照蛆工作前后无明显变化。三组视觉近点比较,发现修布和验布组视觉近点的变化。提示由修布和验布作业引起的视觉疲劳,可以通过测定视觉近点来进行评价。     

Blood Flow Increase by Cervical Spinal Cord Stimulation in Middle Cerebral and Common Carotid Arteries

The effect of spinal cord stimulation (SCS) on cerebral blood flow (CBF) has, in the past, been evaluated by semiquantitative techniques, but has not been used to treat CBF diseases. The aim of this study was to assess the effect of cervical SCS on regional blood flow by both semiquantitative and quantitative methods. Thirty‐five patients with cervical SCS‐implanted devices were enrolled. The following parameters were measured before and after cervical SCS: systolic and diastolic velocity (cm/s) in the middle cerebral artery (MCA) by transcranial Doppler (TCD) and volume blood flow quantification (ml/min) in the common carotid artery (CCA) by color Doppler. During cervical SCS there was a significant and bilateral increase in systolic (21%) and diastolic (26%) velocity in the MCA and in CCA blood flow (50%). We conclude that cervical SCS increases blood flow in the middle cerebral artery and common carotid artery. The consistent increase supports the potential usefulness of cervical SCS as an adjuvant treatment for cerebral blood flow diseases.